1guestfs-hacking(1) Virtualization Support guestfs-hacking(1)
2
6 guestfs-hacking - extending and contributing to libguestfs
7
9 This manual page is for hackers who want to extend libguestfs itself.
10
12 Libguestfs source is located in the github repository
13 https://github.com/libguestfs/libguestfs
14 Large amounts of boilerplate code in libguestfs (RPC, bindings,
16 documentation) are generated. This means that many source files will
17 appear to be missing from a straightforward git checkout. You have to
18 run the generator ("./configure && make -C generator") in order to
19 create those files.
20 Libguestfs uses an autotools-based build system, with the main files
22 being configure.ac and Makefile.am. See "THE BUILD SYSTEM".
23 The generator subdirectory contains the generator, plus files
25 describing the API. The lib subdirectory contains source for the
26 library. The appliance and daemon subdirectories contain the source
27 for the code that builds the appliance, and the code that runs in the
28 appliance respectively. Other directories are covered in the section
29 "SOURCE CODE SUBDIRECTORIES" below.
30 Apart from the fact that all API entry points go via some generated
32 code, the library is straightforward. (In fact, even the generated
33 code is designed to be readable, and should be read as ordinary code).
34 Some actions run entirely in the library, and are written as C
35 functions in files under lib. Others are forwarded to the daemon where
36 (after some generated RPC marshalling) they appear as C functions in
37 files under daemon.
38 To build from source, first read the guestfs-building(1).
40 SOURCE CODE SUBDIRECTORIES
42 There are a lot of subdirectories in the source tree! Which ones
43 should you concentrate on first? lib and daemon which contain the
44 source code of the core library. generator is the code generator
45 described above, so that is important. The Makefile.am in the root
46 directory will tell you in which order the subdirectories get built.
47 And then if you are looking at a particular tool (eg. customize) or
48 language binding (eg. python), go straight to that subdirectory, but
49 remember that if you didn't run the generator yet, then you may find
50 files which appear to be missing.
51 align
53 virt-alignment-scan(1) command and documentation.
54 appliance
56 The libguestfs appliance, build scripts and so on.
57 bash
59 Bash tab-completion scripts.
60 build-aux
62 Various build scripts used by autotools.
63 builder
65 virt-builder(1) command and documentation.
66 cat The virt-cat(1), virt-filesystems(1), virt-log(1), virt-ls(1) and
68 virt-tail(1) commands and documentation.
69 common
71 Various libraries of internal code can be found in the common
72 subdirectory:
73 common/edit
75 Common code for interactively and non-interactively editing
76 files within a libguestfs filesystem.
77 common/errnostring
79 The communication protocol used between the library and the
80 daemon running inside the appliance has to encode errnos as
81 strings, which is handled by this library.
82 common/mlcustomize
84 Library code associated with "virt-customize" but also used in
85 other tools.
86 common/mlgettext
88 Small, generated wrapper which allows libguestfs to be compiled
89 with or without ocaml-gettext. This is generated by
90 ./configure.
91 common/mlpcre
93 Lightweight OCaml bindings for Perl Compatible Regular
94 Expressions (PCRE). Note this is not related in any way to
95 Markus Mottl's ocaml-pcre library.
96 common/mlprogress
98 OCaml bindings for the progress bar functions (see
99 common/progress).
100 common/mlstdutils
102 A library of pure OCaml utility functions used in many places.
103 common/mltools
105 OCaml utility functions only used by the OCaml virt tools (like
106 "virt-sysprep", "virt-customize" etc.)
107 common/mlutils
109 OCaml bindings for C functions in "common/utils", and some
110 POSIX bindings which are missing from the OCaml stdlib.
111 common/mlvisit
113 OCaml bindings for the visit functions (see common/visit).
114 common/mlxml
116 OCaml bindings for the libxml2 library.
117 common/options
119 Common options parsing for guestfish, guestmount and some virt
120 tools.
121 common/parallel
123 A framework used for processing multiple libvirt domains in
124 parallel.
125 common/progress
127 Common code for printing progress bars.
128 common/protocol
130 The XDR-based communication protocol used between the library
131 and the daemon running inside the appliance is defined here.
132 common/qemuopts
134 Mini-library for writing qemu command lines and qemu config
135 files.
136 common/structs
138 Common code for printing and freeing libguestfs structs, used
139 by the library and some tools.
140 common/utils
142 Various utility functions used throughout the library and
143 tools.
144 common/visit
146 Recursively visit a guestfs filesystem hierarchy.
147 common/windows
149 Utility functions for handling Windows drive letters.
150 contrib
152 Outside contributions, experimental parts.
153 customize
155 virt-customize(1) command and documentation.
156 daemon
158 The daemon that runs inside the libguestfs appliance and carries
159 out actions.
160 df virt-df(1) command and documentation.
162 dib virt-dib(1) command and documentation.
164 diff
166 virt-diff(1) command and documentation.
167 docs
169 Miscellaneous manual pages.
170 edit
172 virt-edit(1) command and documentation.
173 examples
175 C API example code.
176 fish
178 guestfish(1), the command-line shell, and various shell scripts
179 built on top such as virt-copy-in(1), virt-copy-out(1),
180 virt-tar-in(1), virt-tar-out(1).
181 format
183 virt-format(1) command and documentation.
184 fuse
186 guestmount(1), FUSE (userspace filesystem) built on top of
187 libguestfs.
188 generator
190 The crucially important generator, used to automatically generate
191 large amounts of boilerplate C code for things like RPC and
192 bindings.
193 get-kernel
195 virt-get-kernel(1) command and documentation.
196 inspector
198 virt-inspector(1), the virtual machine image inspector.
199 lib Source code to the C library.
201 logo
203 Logo used on the website. The fish is called Arthur by the way.
204 m4 M4 macros used by autoconf. See "THE BUILD SYSTEM".
206 make-fs
208 virt-make-fs(1) command and documentation.
209 po Translations of simple gettext strings.
211 po-docs
213 The build infrastructure and PO files for translations of manpages
214 and POD files. Eventually this will be combined with the po
215 directory, but that is rather complicated.
216 rescue
218 virt-rescue(1) command and documentation.
219 resize
221 virt-resize(1) command and documentation.
222 sparsify
224 virt-sparsify(1) command and documentation.
225 sysprep
227 virt-sysprep(1) command and documentation.
228 tests
230 Tests.
231 test-data
233 Files and other test data used by the tests.
234 test-tool
236 Test tool for end users to test if their qemu/kernel combination
237 will work with libguestfs.
238 tmp Used for temporary files when running the tests (instead of /tmp
240 etc). The reason is so that you can run multiple parallel tests of
241 libguestfs without having one set of tests overwriting the
242 appliance created by another.
243 tools
245 Command line tools written in Perl (virt-win-reg(1) and many
246 others).
247 utils
249 Miscellaneous utilities, such as "boot-benchmark".
250 v2v Up to libguestfs > 1.42 this contained the virt-v2v(1) tool, but
252 this has now moved into a separate repository:
253 https://github.com/libguestfs/virt-v2v
254 website
256 The http://libguestfs.org website files.
257 csharp
259 erlang
260 gobject
261 golang
262 haskell
263 java
264 lua
265 ocaml
266 php
267 perl
268 python
269 ruby
270 Language bindings.
271 THE BUILD SYSTEM
273 Libguestfs uses the GNU autotools build system (autoconf, automake,
274 libtool).
275 The ./configure script is generated from configure.ac and
277 m4/guestfs-*.m4. Most of the configure script is split over many m4
278 macro files by topic, for example m4/guestfs-daemon.m4 deals with the
279 dependencies of the daemon.
280 The job of the top level Makefile.am is mainly to list the
282 subdirectories ("SUBDIRS") in the order they should be compiled.
283 common-rules.mk is included in every Makefile.am (top level and
285 subdirectories). subdir-rules.mk is included only in subdirectory
286 Makefile.am files.
287 There are many make targets. Use this command to list them all:
289 make help
291
293 ADDING A NEW API
294 Because large amounts of boilerplate code in libguestfs are generated,
295 this makes it easy to extend the libguestfs API.
296 To add a new API action there are two changes:
298 1. You need to add a description of the call (name, parameters, return
300 type, tests, documentation) to generator/actions_*.ml and possibly
301 generator/proc_nr.ml.
302 There are two sorts of API action, depending on whether the call
304 goes through to the daemon in the appliance, or is serviced
305 entirely by the library (see "ARCHITECTURE" in
306 guestfs-internals(1)). "guestfs_sync" in guestfs(3) is an example
307 of the former, since the sync is done in the appliance.
308 "guestfs_set_trace" in guestfs(3) is an example of the latter,
309 since a trace flag is maintained in the handle and all tracing is
310 done on the library side.
311 Most new actions are of the first type, and get added to the
313 "daemon_functions" list. Each function has a unique procedure
314 number used in the RPC protocol which is assigned to that action
315 when we publish libguestfs and cannot be reused. Take the latest
316 procedure number and increment it.
317 For library-only actions of the second type, add to the
319 "non_daemon_functions" list. Since these functions are serviced by
320 the library and do not travel over the RPC mechanism to the daemon,
321 these functions do not need a procedure number, and so the
322 procedure number is set to -1.
323 2. Implement the action (in C):
325 For daemon actions, implement the function "do_<name>" in the
327 "daemon/" directory.
328 For library actions, implement the function "guestfs_impl_<name>"
330 in the "lib/" directory.
331 In either case, use another function as an example of what to do.
333 3. As an alternative to step 2: Since libguestfs 1.38, daemon actions
335 can be implemented in OCaml. You have to set the "impl = OCaml
336 ..." flag in the generator. Take a look at daemon/file.ml for an
337 example.
338 After making these changes, use "make" to compile.
340 Note that you don’t need to implement the RPC, language bindings,
342 manual pages or anything else. It’s all automatically generated from
343 the OCaml description.
344 Adding tests for an API
346 You can supply zero or as many tests as you want per API call. The
348 tests can either be added as part of the API description
349 (generator/actions_*.ml), or in some rarer cases you may want to drop a
350 script into "tests/*/". Note that adding a script to "tests/*/" is
351 slower, so if possible use the first method.
352 The following describes the test environment used when you add an API
354 test in actions_*.ml.
355 The test environment has 4 block devices:
357 /dev/sda 2 GB
359 General block device for testing.
360 /dev/sdb 2 GB
362 /dev/sdb1 is an ext2 filesystem used for testing filesystem write
363 operations.
364 /dev/sdc 10 MB
366 Used in a few tests where two block devices are needed.
367 /dev/sdd
369 ISO with fixed content (see images/test.iso).
370 To be able to run the tests in a reasonable amount of time, the
372 libguestfs appliance and block devices are reused between tests. So
373 don't try testing "guestfs_kill_subprocess" in guestfs(3) :-x
374 Each test starts with an initial scenario, selected using one of the
376 "Init*" expressions, described in generator/types.ml. These initialize
377 the disks mentioned above in a particular way as documented in
378 types.ml. You should not assume anything about the previous contents
379 of other disks that are not initialized.
380 You can add a prerequisite clause to any individual test. This is a
382 run-time check, which, if it fails, causes the test to be skipped.
383 Useful if testing a command which might not work on all variations of
384 libguestfs builds. A test that has prerequisite of "Always" means to
385 run unconditionally.
386 In addition, packagers can skip individual tests by setting environment
388 variables before running "make check".
389 SKIP_TEST_<CMD>_<NUM>=1
391 eg: "SKIP_TEST_COMMAND_3=1" skips test #3 of "guestfs_command" in
393 guestfs(3).
394 or:
396 SKIP_TEST_<CMD>=1
398 eg: "SKIP_TEST_ZEROFREE=1" skips all "guestfs_zerofree" in guestfs(3)
400 tests.
401 Packagers can run only certain tests by setting for example:
403 TEST_ONLY="vfs_type zerofree"
405 See tests/c-api/tests.c for more details of how these environment
407 variables work.
408 Debugging new APIs
410 Test new actions work before submitting them.
412 You can use guestfish to try out new commands.
414 Debugging the daemon is a problem because it runs inside a minimal
416 environment. However you can fprintf messages in the daemon to stderr,
417 and they will show up if you use "guestfish -v".
418 ADDING A NEW LANGUAGE BINDING
420 All language bindings must be generated by the generator (see the
421 generator subdirectory).
422 There is no documentation for this yet. We suggest you look at an
424 existing binding, eg. generator/ocaml.ml or generator/perl.ml.
425 Adding tests for language bindings
427 Language bindings should come with tests. Previously testing of
429 language bindings was rather ad-hoc, but we have been trying to
430 formalize the set of tests that every language binding should use.
431 Currently only the OCaml and Perl bindings actually implement the full
433 set of tests, and the OCaml bindings are canonical, so you should
434 emulate what the OCaml tests do.
435 This is the numbering scheme used by the tests:
437 - 000+ basic tests:
439 010 load the library
441 020 create
442 030 create-flags
443 040 create multiple handles
444 050 test setting and getting config properties
445 060 explicit close
446 065 implicit close (in GC'd languages)
447 070 optargs
448 080 version
449 090 retvalues
450 - 100 launch, create partitions and LVs and filesystems
452 - 400+ events:
454 410 close event
456 420 log messages
457 430 progress messages
458 - 800+ regression tests (specific to the language)
460 - 900+ any other custom tests for the language
462 To save time when running the tests, only 100, 430, 800+, 900+ should
464 launch the handle.
465 FORMATTING CODE
467 Our C source code generally adheres to some basic code-formatting
468 conventions. The existing code base is not totally consistent on this
469 front, but we do prefer that contributed code be formatted similarly.
470 In short, use spaces-not-TABs for indentation, use 2 spaces for each
471 indentation level, and other than that, follow the K&R style.
472 If you use Emacs, add the following to one of your start-up files
474 (e.g., ~/.emacs), to help ensure that you get indentation right:
475 ;;; In libguestfs, indent with spaces everywhere (not TABs).
477 ;;; Exceptions: Makefile and ChangeLog modes.
478 (add-hook 'find-file-hook
479 '(lambda () (if (and buffer-file-name
480 (string-match "/libguestfs\\>"
481 (buffer-file-name))
482 (not (string-equal mode-name "Change Log"))
483 (not (string-equal mode-name "Makefile")))
484 (setq indent-tabs-mode nil))))
485 ;;; When editing C sources in libguestfs, use this style.
487 (defun libguestfs-c-mode ()
488 "C mode with adjusted defaults for use with libguestfs."
489 (interactive)
490 (c-set-style "K&R")
491 (setq c-indent-level 2)
492 (setq c-basic-offset 2))
493 (add-hook 'c-mode-hook
494 '(lambda () (if (string-match "/libguestfs\\>"
495 (buffer-file-name))
496 (libguestfs-c-mode))))
497 TESTING YOUR CHANGES
499 Turn warnings into errors when developing to make warnings hard to
500 ignore:
501 ./configure --enable-werror
503 Useful targets are:
505 "make check"
507 Runs the regular test suite.
508 This is implemented using the regular automake "TESTS" target. See
510 the automake documentation for details.
511 "make check-valgrind"
513 Runs a subset of the test suite under valgrind.
514 See "VALGRIND" below.
516 "make check-valgrind-local-guests"
518 Runs a subset of the test suite under valgrind using locally
519 installed libvirt guests (read-only).
520 "make check-direct"
522 Runs all tests using default appliance back-end. This only has any
523 effect if a non-default backend was selected using "./configure
524 --with-default-backend=..."
525 "make check-valgrind-direct"
527 Run a subset of the test suite under valgrind using the default
528 appliance back-end.
529 "make check-with-upstream-qemu"
531 Runs all tests using a local qemu binary. It looks for the qemu
532 binary in QEMUDIR (defaults to $HOME/d/qemu), but you can set this
533 to another directory on the command line, eg:
534 make check-with-upstream-qemu QEMUDIR=/usr/src/qemu
536 "make check-with-upstream-libvirt"
538 Runs all tests using a local libvirt. This only has any effect if
539 the libvirt backend was selected using "./configure
540 --with-default-backend=libvirt"
541 It looks for libvirt in LIBVIRTDIR (defaults to $HOME/d/libvirt),
543 but you can set this to another directory on the command line, eg:
544 make check-with-upstream-libvirt LIBVIRTDIR=/usr/src/libvirt
546 "make check-slow"
548 Runs some slow/long-running tests which are not run by default.
549 To mark a test as slow/long-running:
551 • Add it to the list of "TESTS" in the Makefile.am, just like a
553 normal test.
554 • Modify the test so it checks if the "SLOW=1" environment
556 variable is set, and if not set it skips (ie. returns with exit
557 code 77). If using $TEST_FUNCTIONS, you can call the function
558 "slow_test" for this.
559 • Add a variable "SLOW_TESTS" to the Makefile.am listing the slow
561 tests.
562 • Add a rule to the Makefile.am:
564 check-slow:
566 $(MAKE) check TESTS="$(SLOW_TESTS)" SLOW=1
567 "sudo make check-root"
569 Runs some tests which require root privileges. These are supposed
570 to be safe, but take care. You have to run this as root (eg. using
571 sudo(8) explicitly).
572 To mark a test as requiring root:
574 • Add it to the list of "TESTS" in the Makefile.am, just like a
576 normal test.
577 • Modify the test so it checks if euid == 0, and if not set it
579 skips (ie. returns with exit code 77). If using
580 $TEST_FUNCTIONS, you can call the function "root_test" for
581 this.
582 • Add a variable "ROOT_TESTS" to the Makefile.am listing the root
584 tests.
585 • Add a rule to the Makefile.am:
587 check-root:
589 $(MAKE) check TESTS="$(ROOT_TESTS)"
590 "make check-all"
592 Equivalent to running all "make check*" rules except "check-root".
593 "make check-release"
595 Runs a subset of "make check*" rules that are required to pass
596 before a tarball can be released. Currently this is:
597 • check
599 • check-valgrind
601 • check-direct
603 • check-valgrind-direct
605 • check-slow
607 "make installcheck"
609 Run "make check" on the installed copy of libguestfs.
610 The version of installed libguestfs being tested, and the version
612 of the libguestfs source tree must be the same.
613 Do:
615 ./configure
617 make clean ||:
618 make
619 make installcheck
620 VALGRIND
622 When you do "make check-valgrind", it searches for any Makefile.am in
623 the tree that has a "check-valgrind:" target and runs it.
624 Writing the Makefile.am and tests correctly to use valgrind and working
626 with automake parallel tests is subtle.
627 If your tests are run via a shell script wrapper, then in the wrapper
629 use:
630 $VG virt-foo
632 and in the Makefile.am use:
634 check-valgrind:
636 make VG="@VG@" check
637 However, if your binaries run directly from the "TESTS" rule, you have
639 to modify the Makefile.am like this:
640 LOG_COMPILER = $(VG)
642 check-valgrind:
644 make VG="@VG@" check
645 In either case, check that the right program is being tested by
647 examining the tmp/valgrind* log files carefully.
648 SUBMITTING PATCHES
650 Submit patches to the mailing list:
651 http://www.redhat.com/mailman/listinfo/libguestfs and CC to
652 rjones@redhat.com.
653 You do not need to subscribe to the mailing list if you don’t want to.
655 There may be a short delay while your message is moderated.
656 INTERNATIONALIZATION (I18N) SUPPORT
658 We support i18n (gettext anyhow) in the library.
659 However many messages come from the daemon, and we don’t translate
661 those at the moment. One reason is that the appliance generally has
662 all locale files removed from it, because they take up a lot of space.
663 So we'd have to readd some of those, as well as copying our PO files
664 into the appliance.
665 Debugging messages are never translated, since they are intended for
667 the programmers.
668
670 HOW OCAML PROGRAMS ARE COMPILED AND LINKED
671 Mostly this section is "how we make automake & ocamlopt work together"
672 since OCaml programs themselves are easy to compile.
673 Automake has no native support for OCaml programs, ocamlc nor ocamlopt.
675 What we do instead is to treat OCaml programs as C programs which
676 happen to contain these "other objects" ("DEPENDENCIES" in automake-
677 speak) that happen to be the OCaml objects. This works because OCaml
678 programs usually have C files for native bindings etc.
679 So a typical program is described as just its C sources:
681 virt_customize_SOURCES = ... crypt-c.c perl_edit-c.c
683 For programs that have no explicit C sources, we create an empty
685 dummy.c file, and list that instead:
686 virt_resize_SOURCES = dummy.c
688 The OCaml objects which contain most of the code are listed as automake
690 dependencies (other dependencies may also be listed):
691 virt_customize_DEPENDENCIES = ... customize_main.cmx
693 The only other special thing we need to do is to provide a custom link
695 command. This is needed because automake won't assemble the ocamlopt
696 command, the list of objects and the "-cclib" libraries in the correct
697 order otherwise.
698 virt_customize_LINK = \
700 $(top_builddir)/ocaml-link.sh -cclib '-lutils' -- ...
701 The actual rules, which you can examine in customize/Makefile.am, are a
703 little bit more complicated than this because they have to handle:
704 • Compiling for byte code or native code.
706 • The pattern rules needed to compile the OCaml sources to objects.
708 These are now kept in subdir-rules.mk at the top level, which is
710 included in every subdirectory Makefile.am.
711 • Adding OCaml sources files to "EXTRA_DIST".
713 Automake isn't aware of the complete list of sources for a binary,
715 so it will not add them all automatically.
716
718 MAINTAINER MAKEFILE TARGETS
719 These "make" targets probably won’t work and aren't useful unless you
720 are a libguestfs maintainer.
721 make maintainer-commit
723 This commits everything in the working directory with the commit
725 message "Version $(VERSION).". You must update configure.ac, clean and
726 rebuild first.
727 make maintainer-tag
729 This tags the current HEAD commit with the tag "v$(VERSION)" and one of
731 the messages:
732 Version $(VERSION) stable
734 Version $(VERSION) development
736 (See "LIBGUESTFS VERSION NUMBERS" in guestfs(3) for the difference
738 between a stable and development release.)
739 make maintainer-check-authors
741 Check that all authors (found in git commit messages) are included in
743 the generator/authors.ml file.
744 make maintainer-check-extra-dist
746 This rule must be run after "make dist" (so there is a tarball in the
748 working directory). It compares the contents of the tarball with the
749 contents of git to ensure that no files have been missed from
750 Makefile.am "EXTRA_DIST" rules.
751 make maintainer-upload-website
753 This is used by the software used to automate libguestfs releases to
755 copy the libguestfs website to another git repository before it is
756 uploaded to the web server.
757 MAKING A STABLE RELEASE
759 When we make a stable release, there are several steps documented here.
760 See "LIBGUESTFS VERSION NUMBERS" in guestfs(3) for general information
761 about the stable branch policy.
762 • Check "make && make check" works on at least:
764 Fedora (x86-64)
766 Debian (x86-64)
767 Ubuntu (x86-64)
768 Fedora (aarch64)
769 Fedora (ppc64)
770 Fedora (ppc64le)
771 • Check "./configure --without-libvirt" works.
772 • Finalize guestfs-release-notes.pod
774 • Create new stable and development directories under
776 http://libguestfs.org/download.
777 • Edit website/index.html.in.
779 • Set the version (in configure.ac) to the new stable version, ie.
781 1.XX.0, and commit it:
782 ./localconfigure
784 make distclean -k
785 ./localconfigure
786 make && make dist
787 make maintainer-commit
788 make maintainer-tag
789 • Create the stable branch in git:
791 git branch stable-1.XX
793 git push origin stable-1.XX
794 • Do a full release of the stable branch.
796 • Set the version to the next development version and commit that.
798 Optionally do a full release of the development branch.
799
801 This section documents internal functions inside libguestfs and various
802 utilities. It is intended for libguestfs developers only.
803 This section is autogenerated from "/**" comments in source files,
805 which are marked up in POD format.
806 These functions are not publicly exported, and may change or be removed
808 at any time.
809 Subdirectory lib
811 File lib/actions-support.c
812 Helper functions for the actions code in lib/actions-*.c.
814 File lib/appliance-cpu.c
816 The appliance choice of CPU model.
818 Function "lib/appliance-cpu.c:guestfs_int_get_cpu_model"
820 const char *
822 guestfs_int_get_cpu_model (int kvm)
823 Return the right CPU model to use as the qemu "-cpu" parameter or its
825 equivalent in libvirt. This returns:
826 "host"
828 The literal string "host" means use "-cpu host".
829 "max"
831 The literal string "max" means use "-cpu max" (the best possible).
832 This requires awkward translation for libvirt.
833 some string
835 Some string such as "cortex-a57" means use "-cpu cortex-a57".
836 "NULL"
838 "NULL" means no "-cpu" option at all. Note returning "NULL" does
839 not indicate an error.
840 This is made unnecessarily hard and fragile because of two stupid
842 choices in QEMU:
843 • The default for "qemu-system-aarch64 -M virt" is to emulate a
845 "cortex-a15" (WTF?).
846 • We don't know for sure if KVM will work, but "-cpu host" is broken
848 with TCG, so we almost always pass a broken "-cpu" flag if KVM is
849 semi-broken in any way.
850 File lib/appliance-kcmdline.c
852 The appliance kernel command line.
854 Definition "lib/appliance-kcmdline.c:VALID_TERM"
856 #define VALID_TERM
858 Check that the $TERM environment variable is reasonable before we pass
860 it through to the appliance.
861 Function "lib/appliance-kcmdline.c:get_root_uuid_with_file"
863 static char *
865 get_root_uuid_with_file (guestfs_h *g, const char *appliance)
866 Given a disk image containing an extX filesystem, return the UUID.
868 Function "lib/appliance-kcmdline.c:run_qemu_img_dd"
870 static int
872 run_qemu_img_dd (guestfs_h *g, const char *in_file, char *out_file)
873 Read the first 256k bytes of the in_file with qemu-img(1) command and
875 write them into the out_file. That may be useful to get UUID of the
876 QCOW2 disk image with "get_root_uuid_with_file".
877 The function returns zero if successful, otherwise -1.
879 Function "lib/appliance-kcmdline.c:get_root_uuid"
881 static char *
883 get_root_uuid (guestfs_h *g, const char *appliance)
884 Get the UUID from the appliance disk image.
886 Function "lib/appliance-kcmdline.c:guestfs_int_appliance_command_line"
888 char *
890 guestfs_int_appliance_command_line (guestfs_h *g,
891 const char *appliance,
892 int flags)
893 Construct the Linux command line passed to the appliance. This is used
895 by the "direct" and "libvirt" backends, and is simply located in this
896 file because it's a convenient place for this common code.
897 The "appliance" parameter is the filename of the appliance (could be
899 NULL) from which we obtain the root UUID.
900 The "flags" parameter can contain the following flags logically or'd
902 together (or 0):
903 "APPLIANCE_COMMAND_LINE_IS_TCG"
905 If we are launching a qemu TCG guest (ie. KVM is known to be
906 disabled or unavailable). If you don't know, don't pass this flag.
907 Note that this function returns a newly allocated buffer which must be
909 freed by the caller.
910 File lib/appliance-uefi.c
912 Find the UEFI firmware needed to boot the appliance.
914 See also lib/uefi.c (autogenerated file) containing the firmware file
916 locations.
917 Function "lib/appliance-uefi.c:guestfs_int_get_uefi"
919 int
921 guestfs_int_get_uefi (guestfs_h *g, char *const *firmwares,
922 const char **firmware, char **code, char **vars,
923 int *flags)
924 Return the location of firmware needed to boot the appliance. This is
926 aarch64 only currently, since that's the only architecture where UEFI
927 is mandatory (and that only for RHEL).
928 "firmwares" is an optional list of allowed values for the firmware
930 autoselection of libvirt. It is "NULL" to indicate it is not supported.
931 *firmware is set to one of the strings in "firmwares" in case one can
932 be used.
933 *code is initialized with the path to the read-only UEFI code file.
935 *vars is initialized with the path to a copy of the UEFI vars file
936 (which is cleaned up automatically on exit).
937 In case a UEFI firmware is available, either *firmware is set to a
939 non-"NULL" value, or *code and *vars are.
940 *code and *vars should be freed by the caller, and *firmware must not.
942 If the function returns -1 then there was a real error which should
944 cause appliance building to fail (no UEFI firmware is not an error).
945 See also virt-v2v.git/v2v/utils.ml:find_uefi_firmware
947 File lib/appliance.c
949 This file deals with building the libguestfs appliance.
951 Function "lib/appliance.c:guestfs_int_build_appliance"
953 int
955 guestfs_int_build_appliance (guestfs_h *g,
956 char **kernel_rtn,
957 char **initrd_rtn,
958 char **appliance_rtn)
959 Locate or build the appliance.
961 This function locates or builds the appliance as necessary, handling
963 the supermin appliance, caching of supermin-built appliances, or using
964 either a fixed or old-style appliance.
965 The return value is 0 = good, -1 = error. Returned in
967 "appliance.kernel" will be the name of the kernel to use,
968 "appliance.initrd" the name of the initrd, "appliance.image" the name
969 of the ext2 root filesystem. "appliance.image" can be "NULL", meaning
970 that we are using an old-style (non-ext2) appliance. All three strings
971 must be freed by the caller. However the referenced files themselves
972 must not be deleted.
973 The process is as follows:
975 1. Look in "path" which contains a supermin appliance skeleton. If no
977 element has this, skip straight to step 3.
978 2. Call "supermin --build" to build the full appliance (if it needs to
980 be rebuilt). If this is successful, return the full appliance.
981 3. Check "path", looking for a fixed appliance. If one is found,
983 return it.
984 4. Check "path", looking for an old-style appliance. If one is found,
986 return it.
987 The supermin appliance cache directory lives in $TMPDIR/.guestfs-$UID/
989 and consists of up to four files:
990 $TMPDIR/.guestfs-$UID/lock - the supermin lock file
992 $TMPDIR/.guestfs-$UID/appliance.d/kernel - the kernel
993 $TMPDIR/.guestfs-$UID/appliance.d/initrd - the supermin initrd
994 $TMPDIR/.guestfs-$UID/appliance.d/root - the appliance
995 Multiple instances of libguestfs with the same UID may be racing to
997 create an appliance. However (since supermin ≥ 5) supermin provides a
998 --lock flag and atomic update of the appliance.d subdirectory.
999 Function "lib/appliance.c:locate_or_build_appliance"
1001 static int
1003 locate_or_build_appliance (guestfs_h *g,
1004 struct appliance_files *appliance,
1005 const char *path)
1006 Check "path", looking for one of appliances: supermin appliance, fixed
1008 appliance or old-style appliance. If one of the fixed appliances is
1009 found, return it. If the supermin appliance skeleton is found, build
1010 and return appliance.
1011 Return values:
1013 1 = appliance is found, returns C<appliance>,
1015 0 = appliance not found,
1016 -1 = error which aborts the launch process.
1017 Function "lib/appliance.c:search_appliance"
1019 static int
1021 search_appliance (guestfs_h *g, struct appliance_files *appliance)
1022 Search elements of "g->path", returning the first "appliance" element
1024 which matches the predicate function "locate_or_build_appliance".
1025 Return values:
1027 1 = a path element matched, returns C<appliance>,
1029 0 = no path element matched,
1030 -1 = error which aborts the launch process.
1031 Function "lib/appliance.c:build_supermin_appliance"
1033 static int
1035 build_supermin_appliance (guestfs_h *g,
1036 const char *supermin_path,
1037 struct appliance_files *appliance)
1038 Build supermin appliance from "supermin_path" to $TMPDIR/.guestfs-$UID.
1040 Returns: 0 = built or -1 = error (aborts launch).
1042 Function "lib/appliance.c:run_supermin_build"
1044 static int
1046 run_supermin_build (guestfs_h *g,
1047 const char *lockfile,
1048 const char *appliancedir,
1049 const char *supermin_path)
1050 Run "supermin --build" and tell it to generate the appliance.
1052 Function "lib/appliance.c:dir_contains_file"
1054 static int
1056 dir_contains_file (guestfs_h *g, const char *dir, const char *file)
1057 Returns true iff "file" is contained in "dir".
1059 Function "lib/appliance.c:dir_contains_files"
1061 static int
1063 dir_contains_files (guestfs_h *g, const char *dir, ...)
1064 Returns true iff every listed file is contained in "dir".
1066 File lib/command.c
1068 A wrapper for running external commands, loosely based on libvirt's
1070 "virCommand" interface.
1071 In outline to use this interface you must:
1073 1. Create a new command handle:
1075 struct command *cmd;
1077 cmd = guestfs_int_new_command (g);
1078 2. Either add arguments:
1080 guestfs_int_cmd_add_arg (cmd, "qemu-img");
1082 guestfs_int_cmd_add_arg (cmd, "info");
1083 guestfs_int_cmd_add_arg (cmd, filename);
1084 (NB: You don't need to add a "NULL" argument at the end.)
1086 3. Or construct a command using a mix of quoted and unquoted strings.
1088 (This is useful for system(3)/popen("r")-style shell commands, with
1089 the added safety of allowing args to be quoted properly).
1090 guestfs_int_cmd_add_string_unquoted (cmd, "qemu-img info ");
1092 guestfs_int_cmd_add_string_quoted (cmd, filename);
1093 4. Set various flags, such as whether you want to capture errors in
1095 the regular libguestfs error log.
1096 5. Run the command. This is what does the fork(2) call, optionally
1098 loops over the output, and then does a waitpid(3) and returns the
1099 exit status of the command.
1100 r = guestfs_int_cmd_run (cmd);
1102 if (r == -1)
1103 // error
1104 // else test r using the WIF* functions
1105 6. Close the handle:
1107 guestfs_int_cmd_close (cmd);
1109 (or use "CLEANUP_CMD_CLOSE").
1111 Function "lib/command.c:guestfs_int_new_command"
1113 struct command *
1115 guestfs_int_new_command (guestfs_h *g)
1116 Create a new command handle.
1118 Function "lib/command.c:guestfs_int_cmd_add_arg"
1120 void
1122 guestfs_int_cmd_add_arg (struct command *cmd, const char *arg)
1123 Add single arg (for "execv"-style command execution).
1125 Function "lib/command.c:guestfs_int_cmd_add_arg_format"
1127 void
1129 guestfs_int_cmd_add_arg_format (struct command *cmd, const char *fs, ...)
1130 Add single arg (for "execv"-style command execution) using a
1132 printf(3)-style format string.
1133 Function "lib/command.c:guestfs_int_cmd_add_string_unquoted"
1135 void
1137 guestfs_int_cmd_add_string_unquoted (struct command *cmd, const char *str)
1138 Add a string (for system(3)-style command execution).
1140 This variant adds the strings without quoting them, which is dangerous
1142 if the string contains untrusted content.
1143 Function "lib/command.c:guestfs_int_cmd_add_string_quoted"
1145 void
1147 guestfs_int_cmd_add_string_quoted (struct command *cmd, const char *str)
1148 Add a string (for system(3)-style command execution).
1150 The string is enclosed in double quotes, with any special characters
1152 within the string which need escaping done. This is used to add a
1153 single argument to a system(3)-style command string.
1154 Function "lib/command.c:guestfs_int_cmd_set_stdout_callback"
1156 void
1158 guestfs_int_cmd_set_stdout_callback (struct command *cmd,
1159 cmd_stdout_callback stdout_callback,
1160 void *stdout_data, unsigned flags)
1161 Set a callback which will capture stdout.
1163 If flags contains "CMD_STDOUT_FLAG_LINE_BUFFER" (the default), then the
1165 callback is called line by line on the output. If there is a trailing
1166 "\n" then it is automatically removed before the callback is called.
1167 The line buffer is "\0"-terminated.
1168 If flags contains "CMD_STDOUT_FLAG_UNBUFFERED", then buffers are passed
1170 to the callback as it is received from the command. Note in this case
1171 the buffer is not "\0"-terminated, so you need to may attention to the
1172 length field in the callback.
1173 If flags contains "CMD_STDOUT_FLAG_WHOLE_BUFFER", then the callback is
1175 called exactly once, with the entire buffer. Note in this case the
1176 buffer is not "\0"-terminated, so you need to may attention to the
1177 length field in the callback.
1178 Function "lib/command.c:guestfs_int_cmd_set_stderr_to_stdout"
1180 void
1182 guestfs_int_cmd_set_stderr_to_stdout (struct command *cmd)
1183 Equivalent to adding "2>&1" to the end of the command. This is
1185 incompatible with the "capture_errors" flag, because it doesn't make
1186 sense to combine them.
1187 Function "lib/command.c:guestfs_int_cmd_clear_capture_errors"
1189 void
1191 guestfs_int_cmd_clear_capture_errors (struct command *cmd)
1192 Clear the "capture_errors" flag. This means that any errors will go to
1194 stderr, instead of being captured in the event log, and that is usually
1195 undesirable.
1196 Function "lib/command.c:guestfs_int_cmd_clear_close_files"
1198 void
1200 guestfs_int_cmd_clear_close_files (struct command *cmd)
1201 Don't close file descriptors after the fork.
1203 XXX Should allow single fds to be sent to child process.
1205 Function "lib/command.c:guestfs_int_cmd_set_child_callback"
1207 void
1209 guestfs_int_cmd_set_child_callback (struct command *cmd,
1210 cmd_child_callback child_callback,
1211 void *data)
1212 Set a function to be executed in the child, right before the execution.
1214 Can be used to setup the child, for example changing its current
1215 directory.
1216 Function "lib/command.c:guestfs_int_cmd_set_child_rlimit"
1218 void
1220 guestfs_int_cmd_set_child_rlimit (struct command *cmd, int resource, long limit)
1221 Set up child rlimits, in case the process we are running could consume
1223 lots of space or time.
1224 Function "lib/command.c:finish_command"
1226 static void
1228 finish_command (struct command *cmd)
1229 Finish off the command by either "NULL"-terminating the argv array or
1231 adding a terminating "\0" to the string, or die with an internal error
1232 if no command has been added.
1233 Function "lib/command.c:loop"
1235 static int
1237 loop (struct command *cmd)
1238 The loop which reads errors and output and directs it either to the log
1240 or to the stdout callback as appropriate.
1241 Function "lib/command.c:guestfs_int_cmd_run"
1243 int
1245 guestfs_int_cmd_run (struct command *cmd)
1246 Fork, run the command, loop over the output, and waitpid.
1248 Returns the exit status. Test it using "WIF*" macros.
1250 On error: Calls "error" and returns -1.
1252 Function "lib/command.c:guestfs_int_cmd_pipe_run"
1254 int
1256 guestfs_int_cmd_pipe_run (struct command *cmd, const char *mode)
1257 Fork and run the command, but don't wait. Roughly equivalent to
1259 "popen (..., "r"|"w")".
1260 Returns the file descriptor of the pipe, connected to stdout ("r") or
1262 stdin ("w") of the child process.
1263 After reading/writing to this pipe, call "guestfs_int_cmd_pipe_wait" to
1265 wait for the status of the child.
1266 Errors from the subcommand cannot be captured to the error log using
1268 this interface. Instead the caller should call
1269 "guestfs_int_cmd_get_pipe_errors" (after "guestfs_int_cmd_pipe_wait"
1270 returns an error).
1271 Function "lib/command.c:guestfs_int_cmd_pipe_wait"
1273 int
1275 guestfs_int_cmd_pipe_wait (struct command *cmd)
1276 Wait for a subprocess created by "guestfs_int_cmd_pipe_run" to finish.
1278 On error (eg. failed syscall) this returns -1 and sets the error. If
1279 the subcommand fails, then use "WIF*" macros to check this, and call
1280 "guestfs_int_cmd_get_pipe_errors" to read the error messages printed by
1281 the child.
1282 Function "lib/command.c:guestfs_int_cmd_get_pipe_errors"
1284 char *
1286 guestfs_int_cmd_get_pipe_errors (struct command *cmd)
1287 Read the error messages printed by the child. The caller must free the
1289 returned buffer after use.
1290 Function "lib/command.c:guestfs_int_cmd_close"
1292 void
1294 guestfs_int_cmd_close (struct command *cmd)
1295 Close the "cmd" object and free all resources.
1297 Function "lib/command.c:process_line_buffer"
1299 static void
1301 process_line_buffer (struct command *cmd, int closed)
1302 Deal with buffering stdout for the callback.
1304 File lib/conn-socket.c
1306 This file handles connections to the child process where this is done
1308 over regular POSIX sockets.
1309 Function "lib/conn-socket.c:handle_log_message"
1311 static int
1313 handle_log_message (guestfs_h *g,
1314 struct connection_socket *conn)
1315 This is called if "conn->console_sock" becomes ready to read while we
1317 are doing one of the connection operations above. It reads and deals
1318 with the log message.
1319 Returns:
1321 1 log message(s) were handled successfully
1323 0 connection to appliance closed
1325 -1 error
1327 Function "lib/conn-socket.c:guestfs_int_new_conn_socket_listening"
1329 struct connection *
1331 guestfs_int_new_conn_socket_listening (guestfs_h *g,
1332 int daemon_accept_sock,
1333 int console_sock)
1334 Create a new socket connection, listening.
1336 Note that it's OK for "console_sock" to be passed as -1, meaning
1338 there's no console available for this appliance.
1339 After calling this, "daemon_accept_sock" is owned by the connection,
1341 and will be closed properly either in "accept_connection" or
1342 "free_connection".
1343 Function "lib/conn-socket.c:guestfs_int_new_conn_socket_connected"
1345 struct connection *
1347 guestfs_int_new_conn_socket_connected (guestfs_h *g,
1348 int daemon_sock,
1349 int console_sock)
1350 Create a new socket connection, connected.
1352 As above, but the caller passes us a connected "daemon_sock" and
1354 promises not to call "accept_connection".
1355 File lib/create.c
1357 APIs for creating empty disks.
1359 Mostly this consists of wrappers around the qemu-img(1) program.
1361 Definition "lib/create.c:VALID_FORMAT"
1363 #define VALID_FORMAT
1365 Check for valid backing format. Allow any "^[[:alnum]]+$" (in C
1367 locale), but limit the length to something reasonable.
1368 File lib/drives.c
1370 Drives added are stored in an array in the handle. Code here manages
1372 that array and the individual "struct drive" data.
1373 Function "lib/drives.c:create_overlay"
1375 static int
1377 create_overlay (guestfs_h *g, struct drive *drv)
1378 For readonly drives, create an overlay to protect the original drive
1380 content. Note we never need to clean up these overlays since they are
1381 created in the temporary directory and deleted when the handle is
1382 closed.
1383 Function "lib/drives.c:create_drive_file"
1385 static struct drive *
1387 create_drive_file (guestfs_h *g,
1388 const struct drive_create_data *data)
1389 Create and free the "struct drive".
1391 Function "lib/drives.c:create_drive_dev_null"
1393 static struct drive *
1395 create_drive_dev_null (guestfs_h *g,
1396 struct drive_create_data *data)
1397 Create the special /dev/null drive.
1399 Traditionally you have been able to use /dev/null as a filename, as
1401 many times as you like. Ancient KVM (RHEL 5) cannot handle adding
1402 /dev/null readonly. qemu 1.2 + virtio-scsi segfaults when you use any
1403 zero-sized file including /dev/null.
1404 Because of these problems, we replace /dev/null with a non-zero sized
1406 temporary file. This shouldn't make any difference since users are not
1407 supposed to try and access a null drive.
1408 Function "lib/drives.c:drive_to_string"
1410 static char *
1412 drive_to_string (guestfs_h *g, const struct drive *drv)
1413 Convert a "struct drive" to a string for debugging. The caller must
1415 free this string.
1416 Function "lib/drives.c:add_drive_to_handle_at"
1418 static void
1420 add_drive_to_handle_at (guestfs_h *g, struct drive *d, size_t drv_index)
1421 Add "struct drive" to the "g->drives" vector at the given index
1423 "drv_index". If the array isn't large enough it is reallocated. The
1424 index must not contain a drive already.
1425 Function "lib/drives.c:add_drive_to_handle"
1427 static void
1429 add_drive_to_handle (guestfs_h *g, struct drive *d)
1430 Add struct drive to the end of the "g->drives" vector in the handle.
1432 Function "lib/drives.c:guestfs_int_add_dummy_appliance_drive"
1434 void
1436 guestfs_int_add_dummy_appliance_drive (guestfs_h *g)
1437 Called during launch to add a dummy slot to "g->drives".
1439 Function "lib/drives.c:guestfs_int_free_drives"
1441 void
1443 guestfs_int_free_drives (guestfs_h *g)
1444 Free up all the drives in the handle.
1446 Definition "lib/drives.c:VALID_FORMAT"
1448 #define VALID_FORMAT
1450 Check string parameter matches regular expression "^[-_[:alnum:]]+$"
1452 (in C locale).
1453 Definition "lib/drives.c:VALID_DISK_LABEL"
1455 #define VALID_DISK_LABEL
1457 Check the disk label is reasonable. It can't contain certain
1459 characters, eg. '/', ','. However be stricter here and ensure it's
1460 just alphabetic and ≤ 20 characters in length.
1461 Definition "lib/drives.c:VALID_HOSTNAME"
1463 #define VALID_HOSTNAME
1465 Check the server hostname is reasonable.
1467 Function "lib/drives.c:valid_port"
1469 static int
1471 valid_port (int port)
1472 Check the port number is reasonable.
1474 Function "lib/drives.c:valid_blocksize"
1476 static int
1478 valid_blocksize (int blocksize)
1479 Check the block size is reasonable. It can't be other then 512 or
1481 4096.
1482 Function "lib/drives.c:guestfs_int_checkpoint_drives"
1484 size_t
1486 guestfs_int_checkpoint_drives (guestfs_h *g)
1487 Checkpoint and roll back drives, so that groups of drives can be added
1489 atomically. Only used by "guestfs_add_domain" in guestfs(3).
1490 Function "lib/drives.c:guestfs_impl_debug_drives"
1492 char **
1494 guestfs_impl_debug_drives (guestfs_h *g)
1495 Internal function to return the list of drives.
1497 File lib/errors.c
1499 This file handles errors, and also debug, trace and warning messages.
1501 Errors in libguestfs API calls are handled by setting an error message
1503 and optional errno in the handle. The caller has the choice of testing
1504 API calls to find out if they failed and then querying the last error
1505 from the handle, and/or getting a callback.
1506 From the point of view of the library source, generally you should use
1508 the "error" or "perrorf" macros along error paths, eg:
1509 if (something_bad) {
1511 error (g, "something bad happened");
1512 return -1;
1513 }
1514 Make sure to call the "error" or "perrorf" macro exactly once along
1516 each error path, since the handle can only store a single error and the
1517 previous error will be overwritten.
1518 Function "lib/errors.c:guestfs_int_warning"
1520 void
1522 guestfs_int_warning (guestfs_h *g, const char *fs, ...)
1523 Print a warning.
1525 Code should not call this function directly. Use the
1527 "warning (g, fs, ...)" macro.
1528 Warnings are printed unconditionally. We try to make these rare:
1530 Generally speaking, a warning should either be an error, or if it's not
1531 important for end users then it should be a debug message.
1532 Function "lib/errors.c:guestfs_int_debug"
1534 void
1536 guestfs_int_debug (guestfs_h *g, const char *fs, ...)
1537 Print a debug message.
1539 Code should not call this function directly. To add debug messages in
1541 the library, use the "debug (g, fs, ...)" macro. The macro checks if
1542 "g->verbose" is false and avoids the function call, meaning the macro
1543 is more efficient.
1544 Function "lib/errors.c:guestfs_int_trace"
1546 void
1548 guestfs_int_trace (guestfs_h *g, const char *fs, ...)
1549 Print a trace message.
1551 Do not call this function. All calls are generated automatically.
1553 Function "lib/errors.c:guestfs_int_error_errno"
1555 void
1557 guestfs_int_error_errno (guestfs_h *g, int errnum, const char *fs, ...)
1558 Set the last error and errno in the handle, and optionally raise the
1560 error callback if one is defined.
1561 If you don't need to set errno, use the "error (g, fs, ...)" macro
1563 instead of calling this directly. If you need to set errno then there
1564 is no macro wrapper, so calling this function directly is fine.
1565 Function "lib/errors.c:guestfs_int_perrorf"
1567 void
1569 guestfs_int_perrorf (guestfs_h *g, const char *fs, ...)
1570 Similar to perror(3), but it sets the last error in the handle, raises
1572 the error callback if one is defined, and supports format strings.
1573 You should probably use the "perrorf (g, fs, ...)" macro instead of
1575 calling this directly.
1576 Function "lib/errors.c:guestfs_int_launch_failed_error"
1578 void
1580 guestfs_int_launch_failed_error (guestfs_h *g)
1581 Raise a launch failed error in a standard format.
1583 Since this is the most common error seen by people who have
1585 installation problems, buggy qemu, etc, and since no one reads the FAQ,
1586 describe in this error message what resources are available to debug
1587 launch problems.
1588 Function "lib/errors.c:guestfs_int_unexpected_close_error"
1590 void
1592 guestfs_int_unexpected_close_error (guestfs_h *g)
1593 Raise an error if the appliance unexpectedly crashes after launch.
1595 Function "lib/errors.c:guestfs_int_launch_timeout"
1597 void
1599 guestfs_int_launch_timeout (guestfs_h *g)
1600 Raise an error if the appliance hangs during launch.
1602 Function "lib/errors.c:guestfs_int_external_command_failed"
1604 void
1606 guestfs_int_external_command_failed (guestfs_h *g, int status,
1607 const char *cmd_name, const char *extra)
1608 Raise an error if an external command fails.
1610 "status" is the status code of the command (eg. returned from
1612 waitpid(2) or system(3)). This function turns the status code into an
1613 explanatory string.
1614 File lib/events.c
1616 Function "lib/events.c:replace_old_style_event_callback"
1618 static void
1620 replace_old_style_event_callback (guestfs_h *g,
1621 guestfs_event_callback cb,
1622 uint64_t event_bitmask,
1623 void *opaque,
1624 void *opaque2)
1625 Emulate old-style callback API.
1627 There were no event handles, so multiple callbacks per event were not
1629 supported. Calling the same "guestfs_set_*_callback" function would
1630 replace the existing event. Calling it with "cb == NULL" meant that
1631 the caller wanted to remove the callback.
1632 File lib/guestfs-internal-all.h
1634 This header contains definitions which are shared by all parts of
1636 libguestfs, ie. the daemon, the library, language bindings and virt
1637 tools (ie. all C code).
1638 If you need a definition used by only the library, put it in
1640 lib/guestfs-internal.h instead.
1641 If a definition is used by only a single tool, it should not be in any
1643 shared header file at all.
1644 File lib/guestfs-internal.h
1646 This header file is included in the libguestfs library (lib/) only.
1648 See also lib/guestfs-internal-all.h.
1650 Structure "lib/guestfs-internal.h:event"
1652 struct event {
1654 uint64_t event_bitmask;
1655 guestfs_event_callback cb;
1656 void *opaque;
1657 /* opaque2 is not exposed through the API, but is used internally to
1659 * emulate the old-style callback API.
1660 */
1661 void *opaque2;
1662 };
1663 This struct is used to maintain a list of events registered against the
1665 handle. See "g->events" in the handle.
1666 Structure "lib/guestfs-internal.h:drive"
1668 struct drive {
1670 /* Original source of the drive, eg. file:..., http:... */
1671 struct drive_source src;
1672 /* If the drive is readonly, then an overlay [a local file] is
1674 * created before launch to protect the original drive content, and
1675 * the filename is stored here. Backends should open this file if
1676 * it is non-NULL, else consult the original source above.
1677 *
1678 * Note that the overlay is in a backend-specific format, probably
1679 * different from the source format. eg. qcow2
1680 */
1681 char *overlay;
1682 /* Various per-drive flags. */
1684 bool readonly;
1685 char *name;
1686 char *disk_label;
1687 char *cachemode;
1688 enum discard discard;
1689 bool copyonread;
1690 int blocksize;
1691 };
1692 There is one "struct drive" per drive.
1694 Structure "lib/guestfs-internal.h:backend_ops"
1696 struct backend_ops {
1698 /* Size (in bytes) of the per-handle data structure needed by this
1699 * backend. The data pointer is allocated and freed by libguestfs
1700 * and passed to the functions in the 'void *data' parameter.
1701 * Inside the data structure is opaque to libguestfs. Any strings
1702 * etc pointed to by it must be freed by the backend during
1703 * shutdown.
1704 */
1705 size_t data_size;
1706 /* Create a COW overlay on top of a drive. This must be a local
1708 * file, created in the temporary directory. This is called when
1709 * the drive is added to the handle.
1710 */
1711 char *(*create_cow_overlay) (guestfs_h *g, void *data, struct drive *drv);
1712 /* Launch and shut down. */
1714 int (*launch) (guestfs_h *g, void *data, const char *arg);
1715 int (*shutdown) (guestfs_h *g, void *data, int check_for_errors);
1716 /* Miscellaneous. */
1718 int (*get_pid) (guestfs_h *g, void *data);
1719 int (*max_disks) (guestfs_h *g, void *data);
1720 };
1721 Backend operations.
1723 Each backend (eg. libvirt, direct) defines some functions which get run
1725 at various places in the handle lifecycle (eg. at launch, shutdown).
1726 The backend defines this struct pointing to those functions.
1727 Structure "lib/guestfs-internal.h:connection"
1729 struct connection {
1731 const struct connection_ops *ops;
1732 /* In the real struct, private data used by each connection module
1734 * follows here.
1735 */
1736 };
1737 Connection module.
1739 A "connection" represents the appliance console connection plus the
1741 daemon connection. It hides the underlying representation (POSIX
1742 sockets, "virStreamPtr").
1743 Structure "lib/guestfs-internal.h:cached_feature"
1745 struct cached_feature {
1747 char *group;
1748 int result;
1749 };
1750 Cache of queried features.
1752 Used to cache the appliance features (see lib/available.c).
1754 Structure "lib/guestfs-internal.h:guestfs_h"
1756 struct guestfs_h {
1758 struct guestfs_h *next; /* Linked list of open handles. */
1759 enum state state; /* See the state machine diagram in guestfs(3)*/
1760 /* Lock acquired when entering any public guestfs_* function to
1762 * protect the handle.
1763 */
1764 pthread_mutex_t lock;
1765 /**** Configuration of the handle. ****/
1767 bool verbose; /* Debugging. */
1768 bool trace; /* Trace calls. */
1769 bool autosync; /* Autosync. */
1770 bool direct_mode; /* Direct mode. */
1771 bool recovery_proc; /* Create a recovery process. */
1772 bool enable_network; /* Enable the network. */
1773 bool selinux; /* selinux enabled? */
1774 bool pgroup; /* Create process group for children? */
1775 bool close_on_exit; /* Is this handle on the atexit list? */
1776 int smp; /* If > 1, -smp flag passed to hv. */
1778 int memsize; /* Size of RAM (megabytes). */
1779 char *path; /* Path to the appliance. */
1781 char *hv; /* Hypervisor (HV) binary. */
1782 char *append; /* Append to kernel command line. */
1783 struct hv_param *hv_params; /* Extra hv parameters. */
1785 char *program; /* Program name. */
1787 char *identifier; /* Handle identifier. */
1788 /* Array of drives added by add-drive* APIs.
1790 *
1791 * Before launch this list can be empty or contain some drives.
1792 *
1793 * During launch, a dummy slot may be added which represents the
1794 * slot taken up by the appliance drive.
1795 *
1796 * During shutdown, this list is deleted, so that each launch gets a
1797 * fresh set of drives (however callers: don't do this, create a new
1798 * handle each time).
1799 *
1800 * Always use ITER_DRIVES macro to iterate over this list!
1801 */
1802 struct drive **drives;
1803 size_t nr_drives;
1804 #define ITER_DRIVES(g,i,drv) \
1806 for (i = 0; i < (g)->nr_drives; ++i) \
1807 if (((drv) = (g)->drives[i]) != NULL)
1808 /* Backend. NB: Use guestfs_int_set_backend to change the backend. */
1810 char *backend; /* The full string, always non-NULL. */
1811 char *backend_arg; /* Pointer to the argument part. */
1812 const struct backend_ops *backend_ops;
1813 void *backend_data; /* Per-handle data. */
1814 char **backend_settings; /* Backend settings (can be NULL). */
1815 /**** Runtime information. ****/
1817 /* Temporary and cache directories. */
1818 /* The actual temporary directory - this is not created with the
1819 * handle, you have to call guestfs_int_lazy_make_tmpdir.
1820 */
1821 char *tmpdir;
1822 char *sockdir;
1823 /* Environment variables that affect tmpdir/cachedir/sockdir locations. */
1824 char *env_tmpdir; /* $TMPDIR (NULL if not set) */
1825 char *env_runtimedir; /* $XDG_RUNTIME_DIR (NULL if not set)*/
1826 char *int_tmpdir; /* $LIBGUESTFS_TMPDIR or guestfs_set_tmpdir or NULL */
1827 char *int_cachedir; /* $LIBGUESTFS_CACHEDIR or guestfs_set_cachedir or NULL */
1828 /* Error handler, plus stack of old error handlers. */
1830 pthread_key_t error_data;
1831 /* Linked list of error_data structures allocated for this handle,
1833 * plus a mutex to protect the linked list.
1834 */
1835 pthread_mutex_t error_data_list_lock;
1836 struct error_data *error_data_list;
1837 /* Out of memory error handler. */
1839 guestfs_abort_cb abort_cb;
1840 /* Events. */
1842 struct event *events;
1843 size_t nr_events;
1844 /* Private data area. */
1846 struct hash_table *pda;
1847 struct pda_entry *pda_next;
1848 /* User cancelled transfer. Not signal-atomic, but it doesn't
1850 * matter for this case because we only care if it is != 0.
1851 */
1852 int user_cancel;
1853 struct timeval launch_t; /* The time that we called guestfs_launch. */
1855 /* Used by bindtests. */
1857 FILE *test_fp;
1858 /* Used to generate unique numbers, eg for temp files. To use this,
1860 * '++g->unique'. Note these are only unique per-handle, not
1861 * globally unique.
1862 */
1863 int unique;
1864 /*** Protocol. ***/
1866 struct connection *conn; /* Connection to appliance. */
1867 int msg_next_serial;
1868 #if HAVE_FUSE
1870 /**** Used by the mount-local APIs. ****/
1871 char *localmountpoint;
1872 struct fuse *fuse; /* FUSE handle. */
1873 int ml_dir_cache_timeout; /* Directory cache timeout. */
1874 Hash_table *lsc_ht, *xac_ht, *rlc_ht; /* Directory cache. */
1875 int ml_read_only; /* If mounted read-only. */
1876 int ml_debug_calls; /* Extra debug info on each FUSE call. */
1877 #endif
1878 #ifdef HAVE_LIBVIRT
1880 /* Used by lib/libvirt-auth.c. */
1881 #define NR_CREDENTIAL_TYPES 9
1882 unsigned int nr_supported_credentials;
1883 int supported_credentials[NR_CREDENTIAL_TYPES];
1884 const char *saved_libvirt_uri; /* Doesn't need to be freed. */
1885 bool wrapper_warning_done;
1886 unsigned int nr_requested_credentials;
1887 virConnectCredentialPtr requested_credentials;
1888 #endif
1889 /* Cached features. */
1891 struct cached_feature *features;
1892 size_t nr_features;
1893 /* Used by lib/info.c. -1 = not tested or error; else 0 or 1. */
1895 int qemu_img_supports_U_option;
1896 };
1897 The libguestfs handle.
1899 Structure "lib/guestfs-internal.h:version"
1901 struct version {
1903 int v_major;
1904 int v_minor;
1905 int v_micro;
1906 };
1907 Used for storing major.minor.micro version numbers. See lib/version.c
1909 for more information.
1910 File lib/guid.c
1912 Function "lib/guid.c:guestfs_int_validate_guid"
1914 int
1916 guestfs_int_validate_guid (const char *str)
1917 Check whether a string supposed to contain a GUID actually contains it.
1919 It can recognize strings either as
1920 "{21EC2020-3AEA-1069-A2DD-08002B30309D}" or
1921 "21EC2020-3AEA-1069-A2DD-08002B30309D".
1922 File lib/handle.c
1924 This file deals with the "guestfs_h" handle, creating it, closing it,
1926 and initializing/setting/getting fields.
1927 Function "lib/handle.c:init_libguestfs"
1929 static void
1931 init_libguestfs (void)
1932 No initialization is required by libguestfs, but libvirt and libxml2
1934 require initialization if they might be called from multiple threads.
1935 Hence this constructor function which is called when libguestfs is
1936 first loaded.
1937 Function "lib/handle.c:shutdown_backend"
1939 static int
1941 shutdown_backend (guestfs_h *g, int check_for_errors)
1942 This function is the common path for shutting down the backend qemu
1944 process.
1945 "guestfs_shutdown" calls "shutdown_backend" with "check_for_errors=1".
1947 "guestfs_close" calls "shutdown_backend" with "check_for_errors=0".
1948 "check_for_errors" is a hint to the backend about whether we care about
1950 errors or not. In the libvirt case it can be used to optimize the
1951 shutdown for speed when we don't care.
1952 Function "lib/handle.c:close_handles"
1954 static void
1956 close_handles (void)
1957 Close all open handles (called from atexit(3)).
1959 Function "lib/handle.c:guestfs_int_get_backend_setting_bool"
1961 int
1963 guestfs_int_get_backend_setting_bool (guestfs_h *g, const char *name)
1964 This is a convenience function, but we might consider exporting it as
1966 an API in future.
1967 File lib/info.c
1969 Function "lib/info.c:qemu_img_supports_U_option"
1971 static int
1973 qemu_img_supports_U_option (guestfs_h *g)
1974 Test if the qemu-img info command supports the "-U" option to disable
1976 locking. The result is memoized in the handle.
1977 Note this option was added in qemu 2.11. We can remove this test when
1979 we can assume everyone is using qemu >= 2.11.
1980 File lib/inspect-icon.c
1982 Function "lib/inspect-icon.c:guestfs_int_download_to_tmp"
1984 char *
1986 guestfs_int_download_to_tmp (guestfs_h *g, const char *filename,
1987 const char *extension,
1988 uint64_t max_size)
1989 Download a guest file to a local temporary file.
1991 The name of the temporary (downloaded) file is returned. The caller
1993 must free the pointer, but does not need to delete the temporary file.
1994 It will be deleted when the handle is closed.
1995 The name of the temporary file is randomly generated, but an extension
1997 can be specified using "extension" (or pass "NULL" for none).
1998 Refuse to download the guest file if it is larger than "max_size". On
2000 this and other errors, "NULL" is returned.
2001 File lib/launch-direct.c
2003 Implementation of the "direct" backend.
2005 For more details see "BACKENDS" in guestfs(3).
2007 Function "lib/launch-direct.c:add_drive_standard_params"
2009 static int
2011 add_drive_standard_params (guestfs_h *g, struct backend_direct_data *data,
2012 struct qemuopts *qopts,
2013 size_t i, struct drive *drv)
2014 Add the standard elements of the "-drive" parameter.
2016 Function "lib/launch-direct.c:add_device_blocksize_params"
2018 static int
2020 add_device_blocksize_params (guestfs_h *g, struct qemuopts *qopts,
2021 struct drive *drv)
2022 Add the physical_block_size and logical_block_size elements of the
2024 "-device" parameter.
2025 File lib/launch-libvirt.c
2027 Function "lib/launch-libvirt.c:get_source_format_or_autodetect"
2029 static char *
2031 get_source_format_or_autodetect (guestfs_h *g, struct drive *drv)
2032 Return "drv->src.format", but if it is "NULL", autodetect the format.
2034 libvirt has disabled the feature of detecting the disk format, unless
2036 the administrator sets "allow_disk_format_probing=1" in
2037 /etc/libvirt/qemu.conf. There is no way to detect if this option is
2038 set, so we have to do format detection here using "qemu-img" and pass
2039 that to libvirt.
2040 This can still be a security issue, so in most cases it is recommended
2042 the users pass the format to libguestfs which will faithfully pass that
2043 straight through to libvirt without doing autodetection.
2044 Caller must free the returned string. On error this function sets the
2046 error in the handle and returns "NULL".
2047 Function "lib/launch-libvirt.c:make_qcow2_overlay"
2049 static char *
2051 make_qcow2_overlay (guestfs_h *g, const char *backing_drive,
2052 const char *format)
2053 Create a qcow2 format overlay, with the given "backing_drive" (file).
2055 The "format" parameter is the backing file format. The "format"
2056 parameter can be NULL, in this case the backing format will be
2057 determined automatically. This is used to create the appliance
2058 overlay, and also for read-only drives.
2059 File lib/launch.c
2061 This file implements "guestfs_launch" in guestfs(3).
2063 Most of the work is done by the backends (see "BACKEND" in guestfs(3)),
2065 which are implemented in lib/launch-direct.c, lib/launch-libvirt.c etc,
2066 so this file mostly passes calls through to the current backend.
2067 Function "lib/launch.c:guestfs_int_launch_send_progress"
2069 void
2071 guestfs_int_launch_send_progress (guestfs_h *g, int perdozen)
2072 This function sends a launch progress message.
2074 Launching the appliance generates approximate progress messages.
2076 Currently these are defined as follows:
2077 0 / 12: launch clock starts
2079 3 / 12: appliance created
2080 6 / 12: detected that guest kernel started
2081 9 / 12: detected that /init script is running
2082 12 / 12: launch completed successfully
2083 Notes:
2085 1. This is not a documented ABI and the behaviour may be changed or
2087 removed in future.
2088 2. Messages are only sent if more than 5 seconds has elapsed since the
2090 launch clock started.
2091 3. There is a hack in lib/proto.c to make this work.
2093 Function "lib/launch.c:guestfs_int_timeval_diff"
2095 int64_t
2097 guestfs_int_timeval_diff (const struct timeval *x, const struct timeval *y)
2098 Compute "y - x" and return the result in milliseconds.
2100 Approximately the same as this code:
2102 http://www.mpp.mpg.de/~huber/util/timevaldiff.c
2103 Function "lib/launch.c:guestfs_int_unblock_sigterm"
2105 void
2107 guestfs_int_unblock_sigterm (void)
2108 Unblock the "SIGTERM" signal. Call this after fork(2) so that the
2110 parent process can send "SIGTERM" to the child process in case
2111 "SIGTERM" is blocked. See https://bugzilla.redhat.com/1460338.
2112 Function "lib/launch.c:guestfs_impl_max_disks"
2114 int
2116 guestfs_impl_max_disks (guestfs_h *g)
2117 Returns the maximum number of disks allowed to be added to the backend
2119 (backend dependent).
2120 Function "lib/launch.c:guestfs_impl_wait_ready"
2122 int
2124 guestfs_impl_wait_ready (guestfs_h *g)
2125 Implementation of "guestfs_wait_ready" in guestfs(3). You had to call
2127 this function after launch in versions ≤ 1.0.70, but it is now an
2128 (almost) no-op.
2129 Function "lib/launch.c:guestfs_int_create_socketname"
2131 int
2133 guestfs_int_create_socketname (guestfs_h *g, const char *filename,
2134 char (*sockpath)[UNIX_PATH_MAX])
2135 Create the path for a socket with the selected filename in the tmpdir.
2137 Function "lib/launch.c:guestfs_int_register_backend"
2139 void
2141 guestfs_int_register_backend (const char *name, const struct backend_ops *ops)
2142 When the library is loaded, each backend calls this function to
2144 register itself in a global list.
2145 Function "lib/launch.c:guestfs_int_set_backend"
2147 int
2149 guestfs_int_set_backend (guestfs_h *g, const char *method)
2150 Implementation of "guestfs_set_backend" in guestfs(3).
2152 • Callers must ensure this is only called in the config state.
2154 • This shouldn't call "error" since it may be called early in handle
2156 initialization. It can return an error code however.
2157 File lib/private-data.c
2159 Implement a private data area where libguestfs C API users can attach
2161 arbitrary pieces of data to a "guestfs_h" handle.
2162 For more information see "PRIVATE DATA AREA" in guestfs(3).
2164 Language bindings do not generally expose this, largely because in non-
2166 C languages it is easy to associate data with handles in other ways
2167 (using hash tables or maps).
2168 Structure "lib/private-data.c:pda_entry"
2170 struct pda_entry {
2172 char *key; /* key */
2173 void *data; /* opaque user data pointer */
2174 };
2175 The private data area is internally stored as a gnulib hash table
2177 containing "pda_entry" structures.
2178 Note the private data area is allocated lazily, since the vast majority
2180 of callers will never use it. This means "g->pda" is likely to be
2181 "NULL".
2182 File lib/proto.c
2184 This is the code used to send and receive RPC messages and (for certain
2186 types of message) to perform file transfers. This code is driven from
2187 the generated actions (lib/actions-*.c). There are five different
2188 cases to consider:
2189 1. A non-daemon function (eg. "guestfs_set_verbose" in guestfs(3)).
2191 There is no RPC involved at all, it's all handled inside the
2192 library.
2193 2. A simple RPC (eg. "guestfs_mount" in guestfs(3)). We write the
2195 request, then read the reply. The sequence of calls is:
2196 guestfs_int_send
2198 guestfs_int_recv
2199 3. An RPC with "FileIn" parameters (eg. "guestfs_upload" in
2201 guestfs(3)). We write the request, then write the file(s), then
2202 read the reply. The sequence of calls is:
2203 guestfs_int_send
2205 guestfs_int_send_file (possibly multiple times)
2206 guestfs_int_recv
2207 4. An RPC with "FileOut" parameters (eg. "guestfs_download" in
2209 guestfs(3)). We write the request, then read the reply, then read
2210 the file(s). The sequence of calls is:
2211 guestfs_int_send
2213 guestfs_int_recv
2214 guestfs_int_recv_file (possibly multiple times)
2215 5. Both "FileIn" and "FileOut" parameters. There are no calls like
2217 this in the current API, but they would be implemented as a
2218 combination of cases 3 and 4.
2219 All read/write/etc operations are performed using the current
2221 connection module ("g->conn"). During operations the connection module
2222 transparently handles log messages that appear on the console.
2223 Function "lib/proto.c:child_cleanup"
2225 static void
2227 child_cleanup (guestfs_h *g)
2228 This is called if we detect EOF, ie. qemu died.
2230 Function "lib/proto.c:guestfs_int_progress_message_callback"
2232 void
2234 guestfs_int_progress_message_callback (guestfs_h *g,
2235 const guestfs_progress *message)
2236 Convenient wrapper to generate a progress message callback.
2238 Function "lib/proto.c:guestfs_int_log_message_callback"
2240 void
2242 guestfs_int_log_message_callback (guestfs_h *g, const char *buf, size_t len)
2243 Connection modules call us back here when they get a log message.
2245 Function "lib/proto.c:check_daemon_socket"
2247 static ssize_t
2249 check_daemon_socket (guestfs_h *g)
2250 Before writing to the daemon socket, check the read side of the daemon
2252 socket for any of these conditions:
2253 error
2255 return -1
2256 daemon cancellation message
2258 return -2
2259 progress message
2261 handle it here
2262 end of input or appliance exited unexpectedly
2264 return 0
2265 anything else
2267 return 1
2268 Function "lib/proto.c:guestfs_int_send_file"
2270 int
2272 guestfs_int_send_file (guestfs_h *g, const char *filename)
2273 Send a file.
2275 Returns 0 on success, -1 for error, -2 if the daemon cancelled (we must
2277 read the error message).
2278 Function "lib/proto.c:send_file_data"
2280 static int
2282 send_file_data (guestfs_h *g, const char *buf, size_t len)
2283 Send a chunk of file data.
2285 Function "lib/proto.c:send_file_cancellation"
2287 static int
2289 send_file_cancellation (guestfs_h *g)
2290 Send a cancellation message.
2292 Function "lib/proto.c:send_file_complete"
2294 static int
2296 send_file_complete (guestfs_h *g)
2297 Send a file complete chunk.
2299 Function "lib/proto.c:recv_from_daemon"
2301 static int
2303 recv_from_daemon (guestfs_h *g, uint32_t *size_rtn, void **buf_rtn)
2304 This function reads a single message, file chunk, launch flag or
2306 cancellation flag from the daemon. If something was read, it returns
2307 0, otherwise -1.
2308 Both "size_rtn" and "buf_rtn" must be passed by the caller as non-NULL.
2310 *size_rtn returns the size of the returned message or it may be
2312 "GUESTFS_LAUNCH_FLAG" or "GUESTFS_CANCEL_FLAG".
2313 *buf_rtn is returned containing the message (if any) or will be set to
2315 "NULL". *buf_rtn must be freed by the caller.
2316 This checks for EOF (appliance died) and passes that up through the
2318 child_cleanup function above.
2319 Log message, progress messages are handled transparently here.
2321 Function "lib/proto.c:guestfs_int_recv"
2323 int
2325 guestfs_int_recv (guestfs_h *g, const char *fn,
2326 guestfs_message_header *hdr,
2327 guestfs_message_error *err,
2328 xdrproc_t xdrp, char *ret)
2329 Receive a reply.
2331 Function "lib/proto.c:guestfs_int_recv_discard"
2333 int
2335 guestfs_int_recv_discard (guestfs_h *g, const char *fn)
2336 Same as "guestfs_int_recv", but it discards the reply message.
2338 Notes (XXX):
2340 • This returns an int, but all current callers ignore it.
2342 • The error string may end up being set twice on error paths.
2344 Function "lib/proto.c:guestfs_int_recv_file"
2346 int
2348 guestfs_int_recv_file (guestfs_h *g, const char *filename)
2349 Returns -1 = error, 0 = EOF, ">0" = more data
2351 Function "lib/proto.c:receive_file_data"
2353 static ssize_t
2355 receive_file_data (guestfs_h *g, void **buf_r)
2356 Receive a chunk of file data.
2358 Returns -1 = error, 0 = EOF, ">0" = more data
2360 File lib/qemu.c
2362 Functions to handle qemu versions and features.
2364 Function "lib/qemu.c:guestfs_int_test_qemu"
2366 struct qemu_data *
2368 guestfs_int_test_qemu (guestfs_h *g)
2369 Test that the qemu binary (or wrapper) runs, and do "qemu -help" and
2371 other commands so we can find out the version of qemu and what options
2372 this qemu supports.
2373 This caches the results in the cachedir so that as long as the qemu
2375 binary does not change, calling this is effectively free.
2376 Function "lib/qemu.c:cache_filename"
2378 static char *
2380 cache_filename (guestfs_h *g, const char *cachedir,
2381 const struct stat *statbuf, const char *suffix)
2382 Generate the filenames, for the stat file and the other cache files.
2384 By including the size and mtime in the filename we also ensure that the
2386 same user can use multiple versions of qemu without conflicts.
2387 Function "lib/qemu.c:parse_qemu_version"
2389 static void
2391 parse_qemu_version (guestfs_h *g, const char *qemu_help,
2392 struct version *qemu_version)
2393 Parse the first line of "qemu_help" into the major and minor version of
2395 qemu, but don't fail if parsing is not possible.
2396 Function "lib/qemu.c:parse_json"
2398 static void
2400 parse_json (guestfs_h *g, const char *json, json_t **treep)
2401 Parse the json output from QMP. But don't fail if parsing is not
2403 possible.
2404 Function "lib/qemu.c:parse_has_kvm"
2406 static void
2408 parse_has_kvm (guestfs_h *g, const char *json, bool *ret)
2409 Parse the json output from QMP query-kvm to find out if KVM is enabled
2411 on this machine. Don't fail if parsing is not possible, assume KVM is
2412 available.
2413 The JSON output looks like: {"return": {"enabled": true, "present":
2415 true}}
2416 Function "lib/qemu.c:generic_read_cache"
2418 static int
2420 generic_read_cache (guestfs_h *g, const char *filename, char **strp)
2421 Generic functions for reading and writing the cache files, used where
2423 we are just reading and writing plain text strings.
2424 Function "lib/qemu.c:generic_qmp_test"
2426 static int
2428 generic_qmp_test (guestfs_h *g, struct qemu_data *data,
2429 const char *qmp_command,
2430 char **outp)
2431 Run a generic QMP test on the QEMU binary.
2433 Function "lib/qemu.c:guestfs_int_qemu_version"
2435 struct version
2437 guestfs_int_qemu_version (guestfs_h *g, struct qemu_data *data)
2438 Return the parsed version of qemu.
2440 Function "lib/qemu.c:guestfs_int_qemu_supports"
2442 int
2444 guestfs_int_qemu_supports (guestfs_h *g, const struct qemu_data *data,
2445 const char *option)
2446 Test if option is supported by qemu command line (just by grepping the
2448 help text).
2449 Function "lib/qemu.c:guestfs_int_qemu_supports_device"
2451 int
2453 guestfs_int_qemu_supports_device (guestfs_h *g,
2454 const struct qemu_data *data,
2455 const char *device_name)
2456 Test if device is supported by qemu (currently just greps the "qemu
2458 -device ?" output).
2459 Function "lib/qemu.c:guestfs_int_qemu_mandatory_locking"
2461 int
2463 guestfs_int_qemu_mandatory_locking (guestfs_h *g,
2464 const struct qemu_data *data)
2465 Test if the qemu binary uses mandatory file locking, added in QEMU >=
2467 2.10 (but sometimes disabled).
2468 Function "lib/qemu.c:guestfs_int_qemu_escape_param"
2470 char *
2472 guestfs_int_qemu_escape_param (guestfs_h *g, const char *param)
2473 Escape a qemu parameter.
2475 Every "," becomes ",,". The caller must free the returned string.
2477 XXX This functionality is now only used when constructing a qemu-img
2479 command in lib/create.c. We should extend the qemuopts library to
2480 cover this use case.
2481 Function "lib/qemu.c:guestfs_int_drive_source_qemu_param"
2483 char *
2485 guestfs_int_drive_source_qemu_param (guestfs_h *g,
2486 const struct drive_source *src)
2487 Useful function to format a drive + protocol for qemu.
2489 Note that the qemu parameter is the bit after "file=". It is not
2491 escaped here, but would usually be escaped if passed to qemu as part of
2492 a full -drive parameter (but not for qemu-img(1)).
2493 Function "lib/qemu.c:guestfs_int_discard_possible"
2495 bool
2497 guestfs_int_discard_possible (guestfs_h *g, struct drive *drv,
2498 const struct version *qemu_version)
2499 Test if discard is both supported by qemu AND possible with the
2501 underlying file or device. This returns 1 if discard is possible. It
2502 returns 0 if not possible and sets the error to the reason why.
2503 This function is called when the user set "discard == "enable"".
2505 Function "lib/qemu.c:guestfs_int_free_qemu_data"
2507 void
2509 guestfs_int_free_qemu_data (struct qemu_data *data)
2510 Free the "struct qemu_data".
2512 File lib/rescue.c
2514 Support for virt-rescue(1).
2516 File lib/stringsbuf.c
2518 An expandable NULL-terminated vector of strings (like "argv").
2520 Use the "DECLARE_STRINGSBUF" macro to declare the stringsbuf.
2522 Note: Don't confuse this with stringsbuf in the daemon which is a
2524 different type with different methods.
2525 Function "lib/stringsbuf.c:guestfs_int_add_string_nodup"
2527 void
2529 guestfs_int_add_string_nodup (guestfs_h *g, struct stringsbuf *sb, char *str)
2530 Add a string to the end of the list.
2532 This doesn't call strdup(3) on the string, so the string itself is
2534 stored inside the vector.
2535 Function "lib/stringsbuf.c:guestfs_int_add_string"
2537 void
2539 guestfs_int_add_string (guestfs_h *g, struct stringsbuf *sb, const char *str)
2540 Add a string to the end of the list.
2542 This makes a copy of the string.
2544 Function "lib/stringsbuf.c:guestfs_int_add_sprintf"
2546 void
2548 guestfs_int_add_sprintf (guestfs_h *g, struct stringsbuf *sb,
2549 const char *fs, ...)
2550 Add a string to the end of the list.
2552 Uses an sprintf-like format string when creating the string.
2554 Function "lib/stringsbuf.c:guestfs_int_end_stringsbuf"
2556 void
2558 guestfs_int_end_stringsbuf (guestfs_h *g, struct stringsbuf *sb)
2559 Finish the string buffer.
2561 This adds the terminating NULL to the end of the vector.
2563 Function "lib/stringsbuf.c:guestfs_int_free_stringsbuf"
2565 void
2567 guestfs_int_free_stringsbuf (struct stringsbuf *sb)
2568 Free the string buffer and the strings.
2570 File lib/tmpdirs.c
2572 Handle temporary directories.
2574 Function "lib/tmpdirs.c:set_abs_path"
2576 static int
2578 set_abs_path (guestfs_h *g, const char *ctxstr,
2579 const char *tmpdir, char **tmpdir_ret)
2580 We need to make all tmpdir paths absolute because lots of places in the
2582 code assume this. Do it at the time we set the path or read the
2583 environment variable (https://bugzilla.redhat.com/882417).
2584 The "ctxstr" parameter is a string displayed in error messages giving
2586 the context of the operation (eg. name of environment variable being
2587 used, or API function being called).
2588 Function "lib/tmpdirs.c:guestfs_impl_get_tmpdir"
2590 char *
2592 guestfs_impl_get_tmpdir (guestfs_h *g)
2593 Implements the "guestfs_get_tmpdir" API.
2595 Note this actually calculates the tmpdir, so it never returns "NULL".
2597 Function "lib/tmpdirs.c:guestfs_impl_get_cachedir"
2599 char *
2601 guestfs_impl_get_cachedir (guestfs_h *g)
2602 Implements the "guestfs_get_cachedir" API.
2604 Note this actually calculates the cachedir, so it never returns "NULL".
2606 Function "lib/tmpdirs.c:guestfs_impl_get_sockdir"
2608 char *
2610 guestfs_impl_get_sockdir (guestfs_h *g)
2611 Implements the "guestfs_get_sockdir" API.
2613 Note this actually calculates the sockdir, so it never returns "NULL".
2615 Function "lib/tmpdirs.c:guestfs_int_lazy_make_tmpdir"
2617 int
2619 guestfs_int_lazy_make_tmpdir (guestfs_h *g)
2620 The "g->tmpdir" (per-handle temporary directory) is not created when
2622 the handle is created. Instead we create it lazily before the first
2623 time it is used, or during launch.
2624 Function "lib/tmpdirs.c:guestfs_int_make_temp_path"
2626 char *
2628 guestfs_int_make_temp_path (guestfs_h *g,
2629 const char *name, const char *extension)
2630 Generate unique temporary paths for temporary files.
2632 Returns a unique path or NULL on error.
2634 Function "lib/tmpdirs.c:guestfs_int_lazy_make_supermin_appliance_dir"
2636 char *
2638 guestfs_int_lazy_make_supermin_appliance_dir (guestfs_h *g)
2639 Create the supermin appliance directory under cachedir, if it does not
2641 exist.
2642 Sanity-check that the permissions on the cachedir are safe, in case it
2644 has been pre-created maliciously or tampered with.
2645 Returns the directory name which the caller must free.
2647 Function "lib/tmpdirs.c:guestfs_int_recursive_remove_dir"
2649 void
2651 guestfs_int_recursive_remove_dir (guestfs_h *g, const char *dir)
2652 Recursively remove a temporary directory. If removal fails, just
2654 return (it's a temporary directory so it'll eventually be cleaned up by
2655 a temp cleaner).
2656 This is implemented using "rm -rf" because that's simpler and safer.
2658 File lib/umask.c
2660 Return current umask in a thread-safe way.
2662 glibc documents, but does not actually implement, a "getumask(3)" call.
2664 We use "Umask" from /proc/self/status for Linux ≥ 4.7. For older Linux
2666 and other Unix, this file implements an expensive but thread-safe way
2667 to get the current process's umask.
2668 Thanks to: Josh Stone, Jiri Jaburek, Eric Blake.
2670 Function "lib/umask.c:guestfs_int_getumask"
2672 int
2674 guestfs_int_getumask (guestfs_h *g)
2675 Returns the current process's umask. On failure, returns -1 and sets
2677 the error in the guestfs handle.
2678 Function "lib/umask.c:get_umask_from_proc"
2680 static int
2682 get_umask_from_proc (guestfs_h *g)
2683 For Linux ≥ 4.7 get the umask from /proc/self/status.
2685 On failure this returns -1. However if we could not open the /proc
2687 file or find the "Umask" entry in it, return -2 which causes the
2688 fallback path to run.
2689 Function "lib/umask.c:get_umask_from_fork"
2691 static int
2693 get_umask_from_fork (guestfs_h *g)
2694 Fallback method of getting the umask using fork.
2696 File lib/unit-tests.c
2698 Unit tests of internal functions.
2700 These tests may use a libguestfs handle, but must not launch the
2702 handle. Also, avoid long-running tests.
2703 Function "lib/unit-tests.c:test_split"
2705 static void
2707 test_split (void)
2708 Test "guestfs_int_split_string".
2710 Function "lib/unit-tests.c:test_concat"
2712 static void
2714 test_concat (void)
2715 Test "guestfs_int_concat_strings".
2717 Function "lib/unit-tests.c:test_join"
2719 static void
2721 test_join (void)
2722 Test "guestfs_int_join_strings".
2724 Function "lib/unit-tests.c:test_validate_guid"
2726 static void
2728 test_validate_guid (void)
2729 Test "guestfs_int_validate_guid".
2731 Function "lib/unit-tests.c:test_drive_name"
2733 static void
2735 test_drive_name (void)
2736 Test "guestfs_int_drive_name".
2738 Function "lib/unit-tests.c:test_drive_index"
2740 static void
2742 test_drive_index (void)
2743 Test "guestfs_int_drive_index".
2745 Function "lib/unit-tests.c:test_getumask"
2747 static void
2749 test_getumask (void)
2750 Test "guestfs_int_getumask".
2752 Function "lib/unit-tests.c:test_command"
2754 static void
2756 test_command (void)
2757 Test "guestfs_int_new_command" etc.
2759 XXX These tests could be made much more thorough. So far we simply
2761 test that it's not obviously broken.
2762 Function "lib/unit-tests.c:test_qemu_escape_param"
2764 static void
2766 test_qemu_escape_param (void)
2767 Test "guestfs_int_qemu_escape_param"
2769 XXX I wanted to make this test run qemu, passing some parameters which
2771 need to be escaped, but I cannot think of a way to do that without
2772 launching a VM.
2773 Function "lib/unit-tests.c:test_timeval_diff"
2775 static void
2777 test_timeval_diff (void)
2778 Test "guestfs_int_timeval_diff".
2780 File lib/version.c
2782 This file provides simple version number management.
2784 Function "lib/version.c:guestfs_int_version_from_x_y"
2786 int
2788 guestfs_int_version_from_x_y (guestfs_h *g, struct version *v, const char *str)
2789 Parses a version from a string, looking for a "X.Y" pattern.
2791 Returns -1 on failure (like failed integer parsing), 0 on missing
2793 match, and 1 on match and successful parsing. "v" is changed only on
2794 successful match.
2795 Function "lib/version.c:guestfs_int_version_from_x_y_re"
2797 int
2799 guestfs_int_version_from_x_y_re (guestfs_h *g, struct version *v,
2800 const char *str, const pcre2_code *re)
2801 Parses a version from a string, using the specified "re" as regular
2803 expression which must provide (at least) two matches.
2804 Returns -1 on failure (like failed integer parsing), 0 on missing
2806 match, and 1 on match and successful parsing. "v" is changed only on
2807 successful match.
2808 Function "lib/version.c:guestfs_int_version_from_x_y_or_x"
2810 int
2812 guestfs_int_version_from_x_y_or_x (guestfs_h *g, struct version *v,
2813 const char *str)
2814 Parses a version from a string, either looking for a "X.Y" pattern or
2816 considering it as whole integer.
2817 Returns -1 on failure (like failed integer parsing), 0 on missing
2819 match, and 1 on match and successful parsing. "v" is changed only on
2820 successful match.
2821 Function "lib/version.c:guestfs_int_parse_unsigned_int"
2823 int
2825 guestfs_int_parse_unsigned_int (guestfs_h *g, const char *str)
2826 Parse small, unsigned ints, as used in version numbers.
2828 This will fail with an error if trailing characters are found after the
2830 integer.
2831 Returns ≥ 0 on success, or -1 on failure.
2833 File lib/wait.c
2835 Function "lib/wait.c:guestfs_int_waitpid"
2837 int
2839 guestfs_int_waitpid (guestfs_h *g, pid_t pid, int *status, const char *errmsg)
2840 A safe version of waitpid(3) which retries if "EINTR" is returned.
2842 Note: this only needs to be used in the library, or in programs that
2844 install a non-restartable "SIGCHLD" handler (which is not the case for
2845 any current libguestfs virt tools).
2846 If the main program installs a SIGCHLD handler and sets it to be non-
2848 restartable, then what can happen is the library is waiting in a wait
2849 syscall, the child exits, "SIGCHLD" is sent to the process, and the
2850 wait syscall returns "EINTR". Since the library cannot control the
2851 signal handler, we have to instead restart the wait syscall, which is
2852 the purpose of this wrapper.
2853 Function "lib/wait.c:guestfs_int_waitpid_noerror"
2855 void
2857 guestfs_int_waitpid_noerror (pid_t pid)
2858 Like "guestfs_int_waitpid", but ignore errors.
2860 Function "lib/wait.c:guestfs_int_wait4"
2862 int
2864 guestfs_int_wait4 (guestfs_h *g, pid_t pid, int *status,
2865 struct rusage *rusage, const char *errmsg)
2866 A safe version of wait4(2) which retries if "EINTR" is returned.
2868 File lib/whole-file.c
2870 Function "lib/whole-file.c:guestfs_int_read_whole_file"
2872 int
2874 guestfs_int_read_whole_file (guestfs_h *g, const char *filename,
2875 char **data_r, size_t *size_r)
2876 Read the whole file "filename" into a memory buffer.
2878 The memory buffer is initialized and returned in "data_r". The size of
2880 the file in bytes is returned in "size_r". The return buffer must be
2881 freed by the caller.
2882 On error this sets the error in the handle and returns -1.
2884 For the convenience of callers, the returned buffer is NUL-terminated
2886 (the NUL is not included in the size).
2887 The file must be a regular, local, trusted file. In particular, do not
2889 use this function to read files that might be under control of an
2890 untrusted user since that will lead to a denial-of-service attack.
2891 Subdirectory common/edit
2893 File common/edit/file-edit.c
2894 This file implements common file editing in a range of utilities
2896 including guestfish(1), virt-edit(1), virt-customize(1) and
2897 virt-builder(1).
2898 It contains the code for both interactive-(editor-)based editing and
2900 non-interactive editing using Perl snippets.
2901 Function "common/edit/file-edit.c:edit_file_editor"
2903 int
2905 edit_file_editor (guestfs_h *g, const char *filename, const char *editor,
2906 const char *backup_extension, int verbose)
2907 Edit "filename" using the specified "editor" application.
2909 If "backup_extension" is not null, then a copy of "filename" is saved
2911 with "backup_extension" appended to its file name.
2912 If "editor" is null, then the $EDITOR environment variable will be
2914 queried for the editor application, leaving "vi" as fallback if not
2915 set.
2916 Returns -1 for failure, 0 on success, 1 if the editor did not change
2918 the file (e.g. the user closed the editor without saving).
2919 Function "common/edit/file-edit.c:edit_file_perl"
2921 int
2923 edit_file_perl (guestfs_h *g, const char *filename, const char *perl_expr,
2924 const char *backup_extension, int verbose)
2925 Edit "filename" running the specified "perl_expr" using Perl.
2927 If "backup_extension" is not null, then a copy of "filename" is saved
2929 with "backup_extension" appended to its file name.
2930 Returns -1 for failure, 0 on success.
2932 Subdirectory common/options
2934 File common/options/config.c
2935 This file parses the guestfish configuration file, usually
2937 ~/.libguestfs-tools.rc or /etc/libguestfs-tools.conf.
2938 Note that "parse_config" is called very early, before command line
2940 parsing, before the "verbose" flag has been set, even before the global
2941 handle "g" is opened.
2942 File common/options/decrypt.c
2944 This file implements the decryption of disk images, usually done before
2946 mounting their partitions.
2947 Function "common/options/decrypt.c:make_mapname"
2949 static char *
2951 make_mapname (const char *device)
2952 Make a LUKS map name from the partition or logical volume name, eg.
2954 "/dev/vda2" => "cryptvda2", or "/dev/vg-ssd/lv-root7" =>
2955 "cryptvgssdlvroot7". Note that, in logical volume device names,
2956 c_isalnum() eliminates the "/" separator from between the VG and the
2957 LV, so this mapping is not unique; but for our purposes, it will do.
2958 Function "common/options/decrypt.c:inspect_do_decrypt"
2960 void
2962 inspect_do_decrypt (guestfs_h *g, struct key_store *ks)
2963 Simple implementation of decryption: look for any encrypted partitions
2965 and decrypt them, then rescan for VGs.
2966 File common/options/display-options.c
2968 This file contains common code used to implement --short-options and
2970 --long-options in C virt tools. (The equivalent for OCaml virt tools
2971 is implemented by common/mltools/getopt.ml).
2972 These "hidden" options are used to implement bash tab completion.
2974 Function "common/options/display-options.c:display_short_options"
2976 void
2978 display_short_options (const char *format)
2979 Implements the internal "tool --short-options" flag, which just lists
2981 out the short options available. Used by bash completion.
2982 Function "common/options/display-options.c:display_long_options"
2984 void
2986 display_long_options (const struct option *long_options)
2987 Implements the internal "tool --long-options" flag, which just lists
2989 out the long options available. Used by bash completion.
2990 File common/options/domain.c
2992 Implements the guestfish (and other tools) -d option.
2994 Function "common/options/domain.c:add_libvirt_drives"
2996 int
2998 add_libvirt_drives (guestfs_h *g, const char *guest)
2999 This function is called when a user invokes "guestfish -d guest".
3001 Returns the number of drives added ("> 0"), or -1 for failure.
3003 File common/options/inspect.c
3005 This file implements inspecting the guest and mounting the filesystems
3007 found in the right places. It is used by the guestfish(1) -i option
3008 and some utilities such as virt-cat(1).
3009 Function "common/options/inspect.c:inspect_mount_handle"
3011 void
3013 inspect_mount_handle (guestfs_h *g, struct key_store *ks)
3014 This function implements the -i option.
3016 Function "common/options/inspect.c:print_inspect_prompt"
3018 void
3020 print_inspect_prompt (void)
3021 This function is called only if "inspect_mount_root" was called, and
3023 only after we've printed the prompt in interactive mode.
3024 File common/options/keys.c
3026 Function "common/options/keys.c:read_key"
3028 char *
3030 read_key (const char *param)
3031 Read a passphrase ('Key') from /dev/tty with echo off.
3033 The caller (fish/cmds.c) will call free on the string afterwards.
3035 Based on the code in cryptsetup file lib/utils.c.
3036 File common/options/options.c
3038 This file contains common options parsing code used by guestfish and
3040 many other tools which share a common options syntax.
3041 For example, guestfish, virt-cat, virt-ls etc all support the -a
3043 option, and that is handled in all of those tools using a macro
3044 "OPTION_a" defined in fish/options.h.
3045 There are a lot of common global variables used, "drvs" accumulates the
3047 list of drives, "verbose" for the -v flag, and many more.
3048 Function "common/options/options.c:option_a"
3050 void
3052 option_a (const char *arg, const char *format, int blocksize,
3053 struct drv **drvsp)
3054 Handle the guestfish -a option on the command line.
3056 Function "common/options/options.c:option_d"
3058 void
3060 option_d (const char *arg, struct drv **drvsp)
3061 Handle the -d option when passed on the command line.
3063 Function "common/options/options.c:display_mountpoints_on_failure"
3065 static void
3067 display_mountpoints_on_failure (const char *mp_device,
3068 const char *user_supplied_options)
3069 If the -m option fails on any command, display a useful error message
3071 listing the mountpoints.
3072 File common/options/uri.c
3074 This file implements URI parsing for the -a option, in many utilities
3076 including guestfish(1), virt-cat(1), virt-builder(1),
3077 virt-customize(1), etc.
3078 Subdirectory common/parallel
3080 File common/parallel/domains.c
3081 This file is used by "virt-df" and some of the other tools when they
3083 are implicitly asked to operate over all libvirt domains (VMs), for
3084 example when "virt-df" is called without specifying any particular disk
3085 image.
3086 It hides the complexity of querying the list of domains from libvirt.
3088 Function "common/parallel/domains.c:free_domains"
3090 void
3092 free_domains (void)
3093 Frees up everything allocated by "get_all_libvirt_domains".
3095 Function "common/parallel/domains.c:get_all_libvirt_domains"
3097 void
3099 get_all_libvirt_domains (const char *libvirt_uri)
3100 Read all libguest guests into the global variables "domains" and
3102 "nr_domains". The guests are ordered by name. This exits on any
3103 error.
3104 File common/parallel/estimate-max-threads.c
3106 Function "common/parallel/estimate-max-threads.c:estimate_max_threads"
3108 size_t
3110 estimate_max_threads (void)
3111 This function uses the output of "free -m" to estimate how many
3113 libguestfs appliances could be safely started in parallel. Note that
3114 it always returns ≥ 1.
3115 Function "common/parallel/estimate-max-threads.c:read_line_from"
3117 static char *
3119 read_line_from (const char *cmd)
3120 Run external command and read the first line of output.
3122 File common/parallel/parallel.c
3124 This file is used by "virt-df" and some of the other tools when they
3126 need to run multiple parallel libguestfs instances to operate on a
3127 large number of libvirt domains efficiently.
3128 It implements a multithreaded work queue. In addition it reorders the
3130 output so the output still appears in the same order as the input (ie.
3131 still ordered alphabetically).
3132 Function "common/parallel/parallel.c:start_threads"
3134 int
3136 start_threads (size_t option_P, guestfs_h *options_handle, work_fn work)
3137 Run the threads and work through the global list of libvirt domains.
3139 "option_P" is whatever the user passed in the -P option, or 0 if the
3141 user didn't use the -P option (in which case the number of threads is
3142 chosen heuristically).
3143 "options_handle" (which may be "NULL") is the global guestfs handle
3145 created by the options mini-library.
3146 The work function ("work") should do the work (inspecting the domain,
3148 etc.) on domain index "i". However it must not print out any result
3149 directly. Instead it prints anything it needs to the supplied "FILE
3150 *". The work function should return 0 on success or -1 on error.
3151 The "start_threads" function returns 0 if all work items completed
3153 successfully, or -1 if there was an error.
3154 Subdirectory common/progress
3156 File common/progress/progress.c
3157 This file implements the progress bar in guestfish(1), virt-resize(1)
3159 and virt-sparsify(1).
3160 Function "common/progress/progress.c:progress_bar_init"
3162 struct progress_bar *
3164 progress_bar_init (unsigned flags)
3165 Initialize a progress bar struct.
3167 It is intended that you can reuse the same struct for multiple commands
3169 (but only in a single thread). Call "progress_bar_reset" before each
3170 new command.
3171 Function "common/progress/progress.c:progress_bar_free"
3173 void
3175 progress_bar_free (struct progress_bar *bar)
3176 Free a progress bar struct.
3178 Function "common/progress/progress.c:progress_bar_reset"
3180 void
3182 progress_bar_reset (struct progress_bar *bar)
3183 This function should be called just before you issue any command.
3185 Function "common/progress/progress.c:estimate_remaining_time"
3187 static double
3189 estimate_remaining_time (struct progress_bar *bar, double ratio)
3190 Return remaining time estimate (in seconds) for current call.
3192 This returns the running mean estimate of remaining time, but if the
3194 latest estimate of total time is greater than two s.d.'s from the
3195 running mean then we don't print anything because we're not confident
3196 that the estimate is meaningful. (Returned value is <0.0 when nothing
3197 should be printed).
3198 Function "common/progress/progress.c:progress_bar_set"
3200 void
3202 progress_bar_set (struct progress_bar *bar,
3203 uint64_t position, uint64_t total)
3204 Set the position of the progress bar.
3206 This should be called from a "GUESTFS_EVENT_PROGRESS" event callback.
3208 Subdirectory common/qemuopts
3210 File common/qemuopts/qemuopts-tests.c
3211 Unit tests of internal functions.
3213 These tests may use a libguestfs handle, but must not launch the
3215 handle. Also, avoid long-running tests.
3216 File common/qemuopts/qemuopts.c
3218 Mini-library for writing qemu command lines and qemu config files.
3220 There are some shortcomings with the model used for qemu options which
3222 aren't clear until you try to convert options into a configuration
3223 file. However if we attempted to model the options in more detail then
3224 this library would be both very difficult to use and incompatible with
3225 older versions of qemu. Hopefully the current model is a decent
3226 compromise.
3227 For reference here are the problems:
3229 • There's inconsistency in qemu between options and config file, eg.
3231 "-smp 4" becomes:
3232 [smp-opts]
3234 cpus = "4"
3235 • Similar to the previous point, you can write either "-smp 4" or
3237 "-smp cpus=4" (although this won't work in very old qemu). When
3238 generating a config file you need to know the implicit key name.
3239 • In "-opt key=value,..." the "key" is really a tree/array specifier.
3241 The way this works is complicated but hinted at here:
3242 http://git.qemu.org/?p=qemu.git;a=blob;f=util/keyval.c;h=93d5db6b590427e412dfb172f1c406d6dd8958c1;hb=HEAD
3243 • Some options are syntactic sugar. eg. "-kernel foo" is sugar for
3245 "-machine kernel=foo".
3246 Function "common/qemuopts/qemuopts.c:qemuopts_create"
3248 struct qemuopts *
3250 qemuopts_create (void)
3251 Create an empty list of qemu options.
3253 The caller must eventually free the list by calling "qemuopts_free".
3255 Returns "NULL" on error, setting "errno".
3257 Function "common/qemuopts/qemuopts.c:qemuopts_free"
3259 void
3261 qemuopts_free (struct qemuopts *qopts)
3262 Free the list of qemu options.
3264 Function "common/qemuopts/qemuopts.c:qemuopts_add_flag"
3266 int
3268 qemuopts_add_flag (struct qemuopts *qopts, const char *flag)
3269 Add a command line flag which has no argument. eg:
3271 qemuopts_add_flag (qopts, "-no-user-config");
3273 Returns 0 on success. Returns -1 on error, setting "errno".
3275 Function "common/qemuopts/qemuopts.c:qemuopts_add_arg"
3277 int
3279 qemuopts_add_arg (struct qemuopts *qopts, const char *flag, const char *value)
3280 Add a command line flag which has a single argument. eg:
3282 qemuopts_add_arg (qopts, "-m", "1024");
3284 Don't use this if the argument is a comma-separated list, since quoting
3286 will not be done properly. See "qemuopts_add_arg_list".
3287 Returns 0 on success. Returns -1 on error, setting "errno".
3289 Function "common/qemuopts/qemuopts.c:qemuopts_add_arg_format"
3291 int
3293 qemuopts_add_arg_format (struct qemuopts *qopts, const char *flag,
3294 const char *fs, ...)
3295 Add a command line flag which has a single formatted argument. eg:
3297 qemuopts_add_arg_format (qopts, "-m", "%d", 1024);
3299 Don't use this if the argument is a comma-separated list, since quoting
3301 will not be done properly. See "qemuopts_add_arg_list".
3302 Returns 0 on success. Returns -1 on error, setting "errno".
3304 Function "common/qemuopts/qemuopts.c:qemuopts_add_arg_noquote"
3306 int
3308 qemuopts_add_arg_noquote (struct qemuopts *qopts, const char *flag,
3309 const char *value)
3310 This is like "qemuopts_add_arg" except that no quoting is done on the
3312 value.
3313 For "qemuopts_to_script" and "qemuopts_to_channel", this means that
3315 neither shell quoting nor qemu comma quoting is done on the value.
3316 For "qemuopts_to_argv" this means that qemu comma quoting is not done.
3318 "qemuopts_to_config*" will fail.
3320 You should use this with great care.
3322 Function "common/qemuopts/qemuopts.c:qemuopts_start_arg_list"
3324 int
3326 qemuopts_start_arg_list (struct qemuopts *qopts, const char *flag)
3327 Start an argument that takes a comma-separated list of fields.
3329 Typical usage is like this (with error handling omitted):
3331 qemuopts_start_arg_list (qopts, "-drive");
3333 qemuopts_append_arg_list (qopts, "file=foo");
3334 qemuopts_append_arg_list_format (qopts, "if=%s", "ide");
3335 qemuopts_end_arg_list (qopts);
3336 which would construct "-drive file=foo,if=ide"
3338 See also "qemuopts_add_arg_list" for a way to do simple cases in one
3340 call.
3341 Returns 0 on success. Returns -1 on error, setting "errno".
3343 Function "common/qemuopts/qemuopts.c:qemuopts_add_arg_list"
3345 int
3347 qemuopts_add_arg_list (struct qemuopts *qopts, const char *flag,
3348 const char *elem0, ...)
3349 Add a command line flag which has a list of arguments. eg:
3351 qemuopts_add_arg_list (qopts, "-drive", "file=foo", "if=ide", NULL);
3353 This is turned into a comma-separated list, like: "-drive
3355 file=foo,if=ide". Note that this handles qemu quoting properly, so
3356 individual elements may contain commas and this will do the right
3357 thing.
3358 Returns 0 on success. Returns -1 on error, setting "errno".
3360 Function "common/qemuopts/qemuopts.c:qemuopts_set_binary"
3362 int
3364 qemuopts_set_binary (struct qemuopts *qopts, const char *binary)
3365 Set the qemu binary name.
3367 Returns 0 on success. Returns -1 on error, setting "errno".
3369 Function "common/qemuopts/qemuopts.c:qemuopts_set_binary_by_arch"
3371 int
3373 qemuopts_set_binary_by_arch (struct qemuopts *qopts, const char *arch)
3374 Set the qemu binary name to "qemu-system-[arch]".
3376 As a special case if "arch" is "NULL", the binary is set to the KVM
3378 binary for the current host architecture:
3379 qemuopts_set_binary_by_arch (qopts, NULL);
3381 Returns 0 on success. Returns -1 on error, setting "errno".
3383 Function "common/qemuopts/qemuopts.c:qemuopts_to_script"
3385 int
3387 qemuopts_to_script (struct qemuopts *qopts, const char *filename)
3388 Write the qemu options to a script.
3390 "qemuopts_set_binary*" must be called first.
3392 The script file will start with "#!/bin/sh" and will be chmod to mode
3394 0755.
3395 Returns 0 on success. Returns -1 on error, setting "errno".
3397 Function "common/qemuopts/qemuopts.c:shell_quote"
3399 static void
3401 shell_quote (const char *str, FILE *fp)
3402 Print "str" to "fp", shell-quoting it if necessary.
3404 Function "common/qemuopts/qemuopts.c:shell_and_comma_quote"
3406 static void
3408 shell_and_comma_quote (const char *str, FILE *fp)
3409 Print "str" to "fp" doing both shell and qemu comma quoting.
3411 Function "common/qemuopts/qemuopts.c:qemuopts_to_channel"
3413 int
3415 qemuopts_to_channel (struct qemuopts *qopts, FILE *fp)
3416 Write the qemu options to a "FILE *fp".
3418 "qemuopts_set_binary*" must be called first.
3420 Only the qemu command line is written. The caller may need to add
3422 "#!/bin/sh" and may need to chmod the resulting file to 0755.
3423 Returns 0 on success. Returns -1 on error, setting "errno".
3425 Function "common/qemuopts/qemuopts.c:qemuopts_to_argv"
3427 char **
3429 qemuopts_to_argv (struct qemuopts *qopts)
3430 Return a NULL-terminated argument list, of the kind that can be passed
3432 directly to execv(3).
3433 "qemuopts_set_binary*" must be called first. It will be returned as
3435 "argv[0]" in the returned list.
3436 The list of strings and the strings themselves must be freed by the
3438 caller.
3439 Returns "NULL" on error, setting "errno".
3441 Function "common/qemuopts/qemuopts.c:qemuopts_to_config_file"
3443 int
3445 qemuopts_to_config_file (struct qemuopts *qopts, const char *filename)
3446 Write the qemu options to a qemu config file, suitable for reading in
3448 using "qemu -readconfig filename".
3449 Note that qemu config files have limitations on content and quoting, so
3451 not all qemuopts structs can be written (this function returns an error
3452 in these cases). For more information see
3453 https://habkost.net/posts/2016/12/qemu-apis-qemuopts.html
3454 https://bugs.launchpad.net/qemu/+bug/1686364
3455 Also, command line argument names and config file sections sometimes
3457 have different names. For example the equivalent of "-m 1024" is:
3458 [memory]
3460 size = "1024"
3461 This code does not attempt to convert between the two forms. You just
3463 need to know how to do that yourself.
3464 Returns 0 on success. Returns -1 on error, setting "errno".
3466 Function "common/qemuopts/qemuopts.c:qemuopts_to_config_channel"
3468 int
3470 qemuopts_to_config_channel (struct qemuopts *qopts, FILE *fp)
3471 Same as "qemuopts_to_config_file", but this writes to a "FILE *fp".
3473 Subdirectory common/utils
3475 File common/utils/cleanups.c
3476 Libguestfs uses "CLEANUP_*" macros to simplify temporary allocations.
3478 They are implemented using the "__attribute__((cleanup))" feature of
3479 gcc and clang. Typical usage is:
3480 fn ()
3482 {
3483 CLEANUP_FREE char *str = NULL;
3484 str = safe_asprintf (g, "foo");
3485 // str is freed automatically when the function returns
3486 }
3487 There are a few catches to be aware of with the cleanup mechanism:
3489 • If a cleanup variable is not initialized, then you can end up
3491 calling free(3) with an undefined value, resulting in the program
3492 crashing. For this reason, you should usually initialize every
3493 cleanup variable with something, eg. "NULL"
3494 • Don't mark variables holding return values as cleanup variables.
3496 • The main() function shouldn't use cleanup variables since it is
3498 normally exited by calling exit(3), and that doesn't call the
3499 cleanup handlers.
3500 The functions in this file are used internally by the "CLEANUP_*"
3502 macros. Don't call them directly.
3503 File common/utils/gnulib-cleanups.c
3505 Libguestfs uses "CLEANUP_*" macros to simplify temporary allocations.
3507 They are implemented using the "__attribute__((cleanup))" feature of
3508 gcc and clang. Typical usage is:
3509 fn ()
3511 {
3512 CLEANUP_FREE char *str = NULL;
3513 str = safe_asprintf (g, "foo");
3514 // str is freed automatically when the function returns
3515 }
3516 There are a few catches to be aware of with the cleanup mechanism:
3518 • If a cleanup variable is not initialized, then you can end up
3520 calling free(3) with an undefined value, resulting in the program
3521 crashing. For this reason, you should usually initialize every
3522 cleanup variable with something, eg. "NULL"
3523 • Don't mark variables holding return values as cleanup variables.
3525 • The main() function shouldn't use cleanup variables since it is
3527 normally exited by calling exit(3), and that doesn't call the
3528 cleanup handlers.
3529 The functions in this file are used internally by the "CLEANUP_*"
3531 macros. Don't call them directly.
3532 File common/utils/guestfs-utils.h
3534 This header file is included in all "frontend" parts of libguestfs,
3536 namely the library, non-C language bindings, virt tools and tests.
3537 The daemon does not use this header. If you need a place to put
3539 something shared with absolutely everything including the daemon, put
3540 it in lib/guestfs-internal-all.h
3541 If a definition is only needed by a single component of libguestfs (eg.
3543 just the library, or just a single virt tool) then it should not be
3544 here!
3545 File common/utils/libxml2-writer-macros.h
3547 These macros make it easier to write XML. To use them correctly you
3549 must be aware of these assumptions:
3550 • The "xmlTextWriterPtr" is called "xo". It is used implicitly by
3552 all the macros.
3553 • On failure, a function called "xml_error" is called which you must
3555 define (usually as a macro). You must use "CLEANUP_*" macros in
3556 your functions if you want correct cleanup of local variables along
3557 the error path.
3558 • All the "bad" casting is hidden inside the macros.
3560 Definition "common/utils/libxml2-writer-macros.h:start_element"
3562 #define start_element
3564 To define an XML element use:
3566 start_element ("name") {
3568 ...
3569 } end_element ();
3570 which produces "<name>...</name>"
3572 Definition "common/utils/libxml2-writer-macros.h:empty_element"
3574 #define empty_element
3576 To define an empty element:
3578 empty_element ("name");
3580 which produces "<name/>"
3582 Definition "common/utils/libxml2-writer-macros.h:single_element"
3584 #define single_element
3586 To define a single element with no attributes containing some text:
3588 single_element ("name", text);
3590 which produces "<name>text</name>"
3592 Definition "common/utils/libxml2-writer-macros.h:single_element_format"
3594 #define single_element_format
3596 To define a single element with no attributes containing some text
3598 using a format string:
3599 single_element_format ("cores", "%d", nr_cores);
3601 which produces "<cores>4</cores>"
3603 Definition "common/utils/libxml2-writer-macros.h:attribute"
3605 #define attribute
3607 To define an XML element with attributes, use:
3609 start_element ("name") {
3611 attribute ("foo", "bar");
3612 attribute_format ("count", "%d", count);
3613 ...
3614 } end_element ();
3615 which produces "<name foo="bar" count="123">...</name>"
3617 Definition "common/utils/libxml2-writer-macros.h:attribute_ns"
3619 #define attribute_ns
3621 "attribute_ns (prefix, key, namespace_uri, value)" defines a namespaced
3623 attribute.
3624 Definition "common/utils/libxml2-writer-macros.h:string"
3626 #define string
3628 To define a verbatim string, use:
3630 string ("hello");
3632 Definition "common/utils/libxml2-writer-macros.h:string_format"
3634 #define string_format
3636 To define a verbatim string using a format string, use:
3638 string ("%s, world", greeting);
3640 Definition "common/utils/libxml2-writer-macros.h:base64"
3642 #define base64
3644 To write a string encoded as base64:
3646 base64 (data, size);
3648 Definition "common/utils/libxml2-writer-macros.h:comment"
3650 #define comment
3652 To define a comment in the XML, use:
3654 comment ("number of items = %d", nr_items);
3656 File common/utils/stringlists-utils.c
3658 Utility functions used by the library, tools and language bindings.
3660 These functions must not call internal library functions such as
3662 "safe_*", "error" or "perrorf", or any "guestfs_int_*".
3663 Function "common/utils/stringlists-utils.c:guestfs_int_split_string"
3665 char **
3667 guestfs_int_split_string (char sep, const char *str)
3668 Split string at separator character "sep", returning the list of
3670 strings. Returns "NULL" on memory allocation failure.
3671 Note (assuming "sep" is ":"):
3673 "str == NULL"
3675 aborts
3676 "str == """
3678 returns "[]"
3679 "str == "abc""
3681 returns "["abc"]"
3682 "str == ":""
3684 returns "["", ""]"
3685 File common/utils/utils.c
3687 Utility functions used by the library, tools and language bindings.
3689 These functions must not call internal library functions such as
3691 "safe_*", "error" or "perrorf", or any "guestfs_int_*".
3692 Function "common/utils/utils.c:guestfs_int_replace_string"
3694 char *
3696 guestfs_int_replace_string (const char *str, const char *s1, const char *s2)
3697 Replace every instance of "s1" appearing in "str" with "s2". A newly
3699 allocated string is returned which must be freed by the caller. If
3700 allocation fails this can return "NULL".
3701 For example:
3703 replace_string ("abcabb", "ab", "a");
3705 would return "acab".
3707 Function "common/utils/utils.c:guestfs_int_exit_status_to_string"
3709 char *
3711 guestfs_int_exit_status_to_string (int status, const char *cmd_name,
3712 char *buffer, size_t buflen)
3713 Translate a wait/system exit status into a printable string.
3715 Function "common/utils/utils.c:guestfs_int_random_string"
3717 int
3719 guestfs_int_random_string (char *ret, size_t len)
3720 Return a random string of characters.
3722 Notes:
3724 • The "ret" buffer must have length "len+1" in order to store the
3726 final "\0" character.
3727 • There is about 5 bits of randomness per output character (so about
3729 "5*len" bits of randomness in the resulting string).
3730 Function "common/utils/utils.c:guestfs_int_drive_name"
3732 char *
3734 guestfs_int_drive_name (size_t index, char *ret)
3735 This turns a drive index (eg. 27) into a drive name (eg. "ab").
3737 Drive indexes count from 0. The return buffer has to be large enough
3739 for the resulting string, and the returned pointer points to the *end*
3740 of the string.
3741 https://rwmj.wordpress.com/2011/01/09/how-are-linux-drives-named-beyond-drive-26-devsdz/
3743 Function "common/utils/utils.c:guestfs_int_drive_index"
3745 ssize_t
3747 guestfs_int_drive_index (const char *name)
3748 The opposite of "guestfs_int_drive_name". Take a string like "ab" and
3750 return the index (eg 27).
3751 Note that you must remove any prefix such as "hd", "sd" etc, or any
3753 partition number before calling the function.
3754 Function "common/utils/utils.c:guestfs_int_is_true"
3756 int
3758 guestfs_int_is_true (const char *str)
3759 Similar to "Tcl_GetBoolean".
3761 Function "common/utils/utils.c:guestfs_int_string_is_valid"
3763 bool
3765 guestfs_int_string_is_valid (const char *str,
3766 size_t min_length, size_t max_length,
3767 int flags, const char *extra)
3768 Check a string for validity, that it contains only certain characters,
3770 and minimum and maximum length. This function is usually wrapped in a
3771 VALID_* macro, see lib/drives.c for an example.
3772 "str" is the string to check.
3774 "min_length" and "max_length" are the minimum and maximum length
3776 checks. 0 means no check.
3777 The flags control:
3779 "VALID_FLAG_ALPHA"
3781 7-bit ASCII-only alphabetic characters are permitted.
3782 "VALID_FLAG_DIGIT"
3784 7-bit ASCII-only digits are permitted.
3785 "extra" is a set of extra characters permitted, in addition to
3787 alphabetic and/or digits. ("extra = NULL" for no extra).
3788 Returns boolean "true" if the string is valid (passes all the tests),
3790 or "false" if not.
3791 Function "common/utils/utils.c:guestfs_int_fadvise_normal"
3793 void
3795 guestfs_int_fadvise_normal (int fd)
3796 Hint that we will read or write the file descriptor normally.
3798 On Linux, this clears the "FMODE_RANDOM" flag on the file [see below]
3800 and sets the per-file number of readahead pages to equal the block
3801 device readahead setting.
3802 It's OK to call this on a non-file since we ignore failure as it is
3804 only a hint.
3805 Function "common/utils/utils.c:guestfs_int_fadvise_sequential"
3807 void
3809 guestfs_int_fadvise_sequential (int fd)
3810 Hint that we will read or write the file descriptor sequentially.
3812 On Linux, this clears the "FMODE_RANDOM" flag on the file [see below]
3814 and sets the per-file number of readahead pages to twice the block
3815 device readahead setting.
3816 It's OK to call this on a non-file since we ignore failure as it is
3818 only a hint.
3819 Function "common/utils/utils.c:guestfs_int_fadvise_random"
3821 void
3823 guestfs_int_fadvise_random (int fd)
3824 Hint that we will read or write the file descriptor randomly.
3826 On Linux, this sets the "FMODE_RANDOM" flag on the file. The effect of
3828 this flag is to:
3829 • Disable normal sequential file readahead.
3831 • If any read of the file is done which misses in the page cache, 2MB
3833 are read into the page cache. [I think - I'm not sure I totally
3834 understand what this is doing]
3835 It's OK to call this on a non-file since we ignore failure as it is
3837 only a hint.
3838 Function "common/utils/utils.c:guestfs_int_fadvise_noreuse"
3840 void
3842 guestfs_int_fadvise_noreuse (int fd)
3843 Hint that we will access the data only once.
3845 On Linux, this does nothing.
3847 It's OK to call this on a non-file since we ignore failure as it is
3849 only a hint.
3850 Function "common/utils/utils.c:guestfs_int_fadvise_dontneed"
3852 void
3854 guestfs_int_fadvise_dontneed (int fd)
3855 Hint that we will not access the data in the near future.
3857 On Linux, this immediately writes out any dirty pages in the page cache
3859 and then invalidates (drops) all pages associated with this file from
3860 the page cache. Apparently it does this even if the file is opened or
3861 being used by other processes. This setting is not persistent; if you
3862 subsequently read the file it will be cached in the page cache as
3863 normal.
3864 It's OK to call this on a non-file since we ignore failure as it is
3866 only a hint.
3867 Function "common/utils/utils.c:guestfs_int_fadvise_willneed"
3869 void
3871 guestfs_int_fadvise_willneed (int fd)
3872 Hint that we will access the data in the near future.
3874 On Linux, this immediately reads the whole file into the page cache.
3876 This setting is not persistent; subsequently pages may be dropped from
3877 the page cache as normal.
3878 It's OK to call this on a non-file since we ignore failure as it is
3880 only a hint.
3881 Function "common/utils/utils.c:guestfs_int_shell_unquote"
3883 char *
3885 guestfs_int_shell_unquote (const char *str)
3886 Unquote a shell-quoted string.
3888 Augeas passes strings to us which may be quoted, eg. if they come from
3890 files in /etc/sysconfig. This function can do simple unquoting of
3891 these strings.
3892 Note this function does not do variable substitution, since that is
3894 impossible without knowing the file context and indeed the environment
3895 under which the shell script is run. Configuration files should not
3896 use complex quoting.
3897 "str" is the input string from Augeas, a string that may be single- or
3899 double-quoted or may not be quoted. The returned string is unquoted,
3900 and must be freed by the caller. "NULL" is returned on error and
3901 "errno" is set accordingly.
3902 For information on double-quoting in bash, see
3904 https://www.gnu.org/software/bash/manual/html_node/Double-Quotes.html
3905 Function "common/utils/utils.c:guestfs_int_is_reg"
3907 int
3909 guestfs_int_is_reg (int64_t mode)
3910 Return true if the "guestfs_statns" or "guestfs_lstatns" "st_mode"
3912 field represents a regular file.
3913 Function "common/utils/utils.c:guestfs_int_is_dir"
3915 int
3917 guestfs_int_is_dir (int64_t mode)
3918 Return true if the "guestfs_statns" or "guestfs_lstatns" "st_mode"
3920 field represents a directory.
3921 Function "common/utils/utils.c:guestfs_int_is_chr"
3923 int
3925 guestfs_int_is_chr (int64_t mode)
3926 Return true if the "guestfs_statns" or "guestfs_lstatns" "st_mode"
3928 field represents a char device.
3929 Function "common/utils/utils.c:guestfs_int_is_blk"
3931 int
3933 guestfs_int_is_blk (int64_t mode)
3934 Return true if the "guestfs_statns" or "guestfs_lstatns" "st_mode"
3936 field represents a block device.
3937 Function "common/utils/utils.c:guestfs_int_is_fifo"
3939 int
3941 guestfs_int_is_fifo (int64_t mode)
3942 Return true if the "guestfs_statns" or "guestfs_lstatns" "st_mode"
3944 field represents a named pipe (FIFO).
3945 Function "common/utils/utils.c:guestfs_int_is_lnk"
3947 int
3949 guestfs_int_is_lnk (int64_t mode)
3950 Return true if the "guestfs_statns" or "guestfs_lstatns" "st_mode"
3952 field represents a symbolic link.
3953 Function "common/utils/utils.c:guestfs_int_is_sock"
3955 int
3957 guestfs_int_is_sock (int64_t mode)
3958 Return true if the "guestfs_statns" or "guestfs_lstatns" "st_mode"
3960 field represents a Unix domain socket.
3961 Function "common/utils/utils.c:guestfs_int_full_path"
3963 char *
3965 guestfs_int_full_path (const char *dir, const char *name)
3966 Concatenate "dir" and "name" to create a path. This correctly handles
3968 the case of concatenating "/" + "filename" as well as "/dir" +
3969 "filename". "name" may be "NULL".
3970 The caller must free the returned path.
3972 This function sets "errno" and returns "NULL" on error.
3974 Function "common/utils/utils.c:guestfs_int_hexdump"
3976 void
3978 guestfs_int_hexdump (const void *data, size_t len, FILE *fp)
3979 Hexdump a block of memory to "FILE *", used for debugging.
3981 Function "common/utils/utils.c:guestfs_int_strerror"
3983 const char *
3985 guestfs_int_strerror (int errnum, char *buf, size_t buflen)
3986 Thread-safe strerror_r.
3988 This is a wrapper around the two variants of strerror_r(3) in glibc
3990 since it is hard to use correctly (RHBZ#2030396).
3991 The buffer passed in should be large enough to store the error message
3993 (256 chars at least) and should be non-static. Note that the buffer
3994 might not be used, use the return value.
3995 Subdirectory common/visit
3997 File common/visit/visit.c
3998 This file contains a recursive function for visiting all files and
4000 directories in a guestfs filesystem.
4001 Adapted from
4003 https://rwmj.wordpress.com/2010/12/15/tip-audit-virtual-machine-for-setuid-files/
4004 Function "common/visit/visit.c:visit"
4006 int
4008 visit (guestfs_h *g, const char *dir, visitor_function f, void *opaque)
4009 Visit every file and directory in a guestfs filesystem, starting at
4011 "dir".
4012 "dir" may be "/" to visit the entire filesystem, or may be some
4014 subdirectory. Symbolic links are not followed.
4015 The visitor function "f" is called once for every directory and every
4017 file. The parameters passed to "f" include the current directory name,
4018 the current file name (or "NULL" when we're visiting a directory), the
4019 "guestfs_statns" (file permissions etc), and the list of extended
4020 attributes of the file. The visitor function may return -1 which
4021 causes the whole recursion to stop with an error.
4022 Also passed to this function is an "opaque" pointer which is passed
4024 through to the visitor function.
4025 Returns 0 if everything went OK, or -1 if there was an error. Error
4027 handling is not particularly well defined. It will either set an error
4028 in the libguestfs handle or print an error on stderr, but there is no
4029 way for the caller to tell the difference.
4030 Subdirectory common/windows
4032 File common/windows/windows.c
4033 This file implements "win:" Windows file path support in guestfish(1).
4035 Function "common/windows/windows.c:is_windows"
4037 int
4039 is_windows (guestfs_h *g, const char *root)
4040 Checks whether "root" is a Windows installation.
4042 This relies on an already being done introspection.
4044 Function "common/windows/windows.c:windows_path"
4046 char *
4048 windows_path (guestfs_h *g, const char *root, const char *path, int readonly)
4049 Resolves "path" as possible Windows path according to "root", giving a
4051 new path that can be used in libguestfs API calls.
4052 Notes:
4054 • "root" must be a Windows installation
4056 • relies on an already being done introspection
4058 • will unmount all the existing mount points and mount the Windows
4060 root (according to "readonly")
4061 • calls exit(3) on memory allocation failures
4063 Subdirectory daemon
4065 File daemon/command.c
4066 This file contains a number of useful functions for running external
4068 commands and capturing their output.
4069 Function "daemon/command.c:commandf"
4071 int
4073 commandf (char **stdoutput, char **stderror, unsigned flags,
4074 const char *name, ...)
4075 Run a command. Optionally capture stdout and stderr as strings.
4077 Returns 0 if the command ran successfully, or -1 if there was any
4079 error.
4080 For a description of the "flags" see "commandrvf".
4082 There is also a macro "command(out,err,name,...)" which calls
4084 "commandf" with "flags=0".
4085 Function "daemon/command.c:commandrf"
4087 int
4089 commandrf (char **stdoutput, char **stderror, unsigned flags,
4090 const char *name, ...)
4091 Same as "command", but we allow the status code from the subcommand to
4093 be non-zero, and return that status code.
4094 We still return -1 if there was some other error.
4096 There is also a macro "commandr(out,err,name,...)" which calls
4098 "commandrf" with "flags=0".
4099 Function "daemon/command.c:commandvf"
4101 int
4103 commandvf (char **stdoutput, char **stderror, unsigned flags,
4104 char const *const *argv)
4105 Same as "command", but passing in an argv array.
4107 There is also a macro "commandv(out,err,argv)" which calls "commandvf"
4109 with "flags=0".
4110 Function "daemon/command.c:commandrvf"
4112 int
4114 commandrvf (char **stdoutput, char **stderror, unsigned flags,
4115 char const* const *argv)
4116 This is a more sane version of system(3) for running external commands.
4118 It uses fork/execvp, so we don't need to worry about quoting of
4119 parameters, and it allows us to capture any error messages in a buffer.
4120 If "stdoutput" is not "NULL", then *stdoutput will return the stdout of
4122 the command as a string.
4123 If "stderror" is not "NULL", then *stderror will return the stderr of
4125 the command. If there is a final \n character, it is removed so you
4126 can use the error string directly in a call to "reply_with_error".
4127 Flags are:
4129 "COMMAND_FLAG_FOLD_STDOUT_ON_STDERR"
4131 For broken external commands that send error messages to stdout
4132 (hello, parted) but that don't have any useful stdout information,
4133 use this flag to capture the error messages in the *stderror
4134 buffer. If using this flag, you should pass "stdoutput=NULL"
4135 because nothing could ever be captured in that buffer.
4136 "COMMAND_FLAG_CHROOT_COPY_FILE_TO_STDIN"
4138 For running external commands on chrooted files correctly (see
4139 https://bugzilla.redhat.com/579608) specifying this flag causes
4140 another process to be forked which chroots into sysroot and just
4141 copies the input file to stdin of the specified command. The file
4142 descriptor is ORed with the flags, and that file descriptor is
4143 always closed by this function. See daemon/hexdump.c for an
4144 example of usage.
4145 There is also a macro "commandrv(out,err,argv)" which calls
4147 "commandrvf" with "flags=0".
4148 File daemon/device-name-translation.c
4150 Function
4152 "daemon/device-name-translation.c:device_name_translation_init"
4153 void
4155 device_name_translation_init (void)
4156 Cache daemon disk mapping.
4158 When the daemon starts up, populate a cache with the contents of
4160 /dev/disk/by-path. It's easiest to use "ls -lv" here since the names
4161 are sorted awkwardly.
4162 Function "daemon/device-name-translation.c:device_name_translation"
4164 char *
4166 device_name_translation (const char *device)
4167 Perform device name translation.
4169 Libguestfs defines a few standard formats for device names. (see also
4171 "BLOCK DEVICE NAMING" in guestfs(3) and "guestfs_canonical_device_name"
4172 in guestfs(3)). They are:
4173 /dev/sdX[N]
4175 /dev/hdX[N]
4176 /dev/vdX[N]
4177 These mean the Nth partition on the Xth device. Because Linux no
4178 longer enumerates devices in the order they are passed to qemu, we
4179 must translate these by looking up the actual device using
4180 /dev/disk/by-path/
4181 /dev/mdX
4183 /dev/VG/LV
4184 /dev/mapper/...
4185 /dev/dm-N
4186 These are not translated here.
4187 It returns a newly allocated string which the caller must free.
4189 It returns "NULL" on error. Note it does not call "reply_with_*".
4191 We have to open the device and test for "ENXIO", because the device
4193 nodes may exist in the appliance.
4194 File daemon/guestfsd.c
4196 This is the guestfs daemon which runs inside the guestfs appliance.
4198 This file handles start up and connecting back to the library.
4199 Function "daemon/guestfsd.c:shell_quote"
4201 void
4203 shell_quote (const char *str, FILE *fp)
4204 Write "str" to the file "fp", ensuring it is shell quoted.
4206 Function "daemon/guestfsd.c:sysroot_shell_quote"
4208 void
4210 sysroot_shell_quote (const char *path, FILE *fp)
4211 Write "sysroot" + "path" to the file "fp", ensuring it is shell quoted.
4213 The path must be an absolute path.
4214 File daemon/internal.c
4216 Internal functions that are not part of the public API.
4218 File daemon/utils-c.c
4220 Bindings for utility functions.
4222 Note that functions called from OCaml code must never call any of the
4224 "reply*" functions.
4225 File daemon/utils.c
4227 Miscellaneous utility functions used by the daemon.
4229 Function "daemon/utils.c:is_root_device_stat"
4231 static int
4233 is_root_device_stat (struct stat *statbuf)
4234 Return true iff device is the root device (and therefore should be
4236 ignored from the point of view of user calls).
4237 Function "daemon/utils.c:is_device_parameter"
4239 int
4241 is_device_parameter (const char *device)
4242 Parameters marked as "Device", "Dev_or_Path", etc can be passed a block
4244 device name. This function tests if the parameter is a block device
4245 name.
4246 It can also be used in daemon code to test if the string passed as a
4248 "Dev_or_Path" parameter is a device or path.
4249 Function "daemon/utils.c:sysroot_path"
4251 char *
4253 sysroot_path (const char *path)
4254 Turn "/path" into "/sysroot/path".
4256 Returns "NULL" on failure. The caller must check for this and call
4258 "reply_with_perror ("malloc")". The caller must also free the returned
4259 string.
4260 See also the custom %R printf formatter which does shell quoting too.
4262 Function "daemon/utils.c:sysroot_realpath"
4264 char *
4266 sysroot_realpath (const char *path)
4267 Resolve path within sysroot, calling "sysroot_path" on the resolved
4269 path.
4270 Returns "NULL" on failure. The caller must check for this and call
4272 "reply_with_perror ("malloc")". The caller must also free the returned
4273 string.
4274 See also the custom %R printf formatter which does shell quoting too.
4276 Function "daemon/utils.c:is_power_of_2"
4278 int
4280 is_power_of_2 (unsigned long v)
4281 Returns true if "v" is a power of 2.
4283 Uses the algorithm described at
4285 http://graphics.stanford.edu/~seander/bithacks.html#DetermineIfPowerOf2
4286 Function "daemon/utils.c:split_lines_sb"
4288 struct stringsbuf
4290 split_lines_sb (char *str)
4291 Split an output string into a NULL-terminated list of lines, wrapped
4293 into a stringsbuf.
4294 Typically this is used where we have run an external command which has
4296 printed out a list of things, and we want to return an actual list.
4297 The corner cases here are quite tricky. Note in particular:
4299 "" returns "[]"
4301 "\n"
4303 returns "[""]"
4304 "a\nb"
4306 returns "["a"; "b"]"
4307 "a\nb\n"
4309 returns "["a"; "b"]"
4310 "a\nb\n\n"
4312 returns "["a"; "b"; ""]"
4313 The original string is written over and destroyed by this function
4315 (which is usually OK because it's the 'out' string from "command*()").
4316 You can free the original string, because add_string() strdups the
4317 strings.
4318 "argv" in the "struct stringsbuf" will be "NULL" in case of errors.
4320 Function "daemon/utils.c:filter_list"
4322 char **
4324 filter_list (bool (*p) (const char *str), char **strs)
4325 Filter a list of strings. Returns a newly allocated list of only the
4327 strings where "p (str) == true".
4328 Note it does not copy the strings, be careful not to double-free them.
4330 Function "daemon/utils.c:trim"
4332 void
4334 trim (char *str)
4335 Skip leading and trailing whitespace, updating the original string in-
4337 place.
4338 Function "daemon/utils.c:parse_btrfsvol"
4340 int
4342 parse_btrfsvol (const char *desc_orig, mountable_t *mountable)
4343 Parse the mountable descriptor for a btrfs subvolume. Don't call this
4345 directly; it is only used from the stubs.
4346 A btrfs subvolume is given as:
4348 btrfsvol:/dev/sda3/root
4350 where /dev/sda3 is a block device containing a btrfs filesystem, and
4352 root is the name of a subvolume on it. This function is passed the
4353 string following "btrfsvol:".
4354 On success, "mountable->device" and "mountable->volume" must be freed
4356 by the caller.
4357 Function "daemon/utils.c:mountable_to_string"
4359 char *
4361 mountable_to_string (const mountable_t *mountable)
4362 Convert a "mountable_t" back to its string representation
4364 This function can be used in an error path, so must not call
4366 "reply_with_error".
4367 Function "daemon/utils.c:prog_exists"
4369 int
4371 prog_exists (const char *prog)
4372 Check program exists and is executable on $PATH.
4374 Function "daemon/utils.c:random_name"
4376 int
4378 random_name (char *template)
4379 Pass a template such as "/sysroot/XXXXXXXX.XXX". This updates the
4381 template to contain a randomly named file. Any 'X' characters after
4382 the final '/' in the template are replaced with random characters.
4383 Notes: You should probably use an 8.3 path, so it's compatible with all
4385 filesystems including basic FAT. Also this only substitutes lowercase
4386 ASCII letters and numbers, again for compatibility with lowest common
4387 denominator filesystems.
4388 This doesn't create a file or check whether or not the file exists (it
4390 would be extremely unlikely to exist as long as the RNG is working).
4391 If there is an error, -1 is returned.
4393 Function "daemon/utils.c:udev_settle_file"
4395 void
4397 udev_settle_file (const char *file)
4398 LVM and other commands aren't synchronous, especially when udev is
4400 involved. eg. You can create or remove some device, but the "/dev"
4401 device node won't appear until some time later. This means that you
4402 get an error if you run one command followed by another.
4403 Use "udevadm settle" after certain commands, but don't be too fussed if
4405 it fails.
4406 Function "daemon/utils.c:make_exclude_from_file"
4408 char *
4410 make_exclude_from_file (const char *function, char *const *excludes)
4411 Turn list "excludes" into a temporary file, and return a string
4413 containing the temporary file name. Caller must unlink the file and
4414 free the string.
4415 "function" is the function that invoked this helper, and it is used
4417 mainly for errors/debugging.
4418 Function "daemon/utils.c:read_whole_file"
4420 char *
4422 read_whole_file (const char *filename, size_t *size_r)
4423 Read whole file into dynamically allocated array. If there is an
4425 error, DON'T call reply_with_perror, just return NULL. Returns a
4426 "\0"-terminated string. "size_r" can be specified to get the size of
4427 the returned data.
4428 File daemon/xattr.c
4430 Function "daemon/xattr.c:split_attr_names"
4432 static char **
4434 split_attr_names (char *buf, size_t len)
4435 listxattr(2) returns the string "foo\0bar\0baz" of length "len". (The
4437 last string in the list is \0-terminated but the \0 is not included in
4438 "len").
4439 This function splits it into a regular list of strings.
4441 Note that the returned list contains pointers to the original strings
4443 in "buf" so be careful that you do not double-free them.
4444 Subdirectory fish
4446 File fish/alloc.c
4447 This file implements the guestfish "alloc" and "sparse" commands.
4449 Function "fish/alloc.c:alloc_disk"
4451 int
4453 alloc_disk (const char *filename, const char *size_str, int add, int sparse)
4454 This is the underlying allocation function. It's called from a few
4456 other places in guestfish.
4457 File fish/copy.c
4459 This file implements the guestfish commands "copy-in" and "copy-out".
4461 File fish/destpaths.c
4463 The file handles tab-completion of filesystem paths in guestfish.
4465 File fish/display.c
4467 The file implements the guestfish "display" command, for displaying
4469 graphical files (icons, images) in disk images.
4470 File fish/echo.c
4472 The file implements the guestfish "echo" command.
4474 File fish/edit.c
4476 guestfish "edit" command, suggested by Ján Ondrej.
4478 File fish/events.c
4480 This file implements the guestfish event-related commands, "event",
4482 "delete-event" and "list-events".
4483 File fish/fish.c
4485 guestfish, the guest filesystem shell. This file contains the main
4487 loop and utilities.
4488 Function "fish/fish.c:parse_command_line"
4490 static struct parsed_command
4492 parse_command_line (char *buf, int *exit_on_error_rtn)
4493 Parse a command string, splitting at whitespace, handling '!', '#' etc.
4495 This destructively updates "buf".
4496 "exit_on_error_rtn" is used to pass in the global "exit_on_error"
4498 setting and to return the local setting (eg. if the command begins with
4499 '-').
4500 Returns in "parsed_command.status":
4502 1 got a guestfish command (returned in
4504 "cmd_rtn"/"argv_rtn"/"pipe_rtn")
4505 0 no guestfish command, but otherwise OK
4507 -1 an error
4509 Function "fish/fish.c:parse_quoted_string"
4511 static ssize_t
4513 parse_quoted_string (char *p)
4514 Parse double-quoted strings, replacing backslash escape sequences with
4516 the true character. Since the string is returned in place, the escapes
4517 must make the string shorter.
4518 Function "fish/fish.c:execute_and_inline"
4520 static int
4522 execute_and_inline (const char *cmd, int global_exit_on_error)
4523 Used to handle "<!" (execute command and inline result).
4525 Function "fish/fish.c:issue_command"
4527 int
4529 issue_command (const char *cmd, char *argv[], const char *pipecmd,
4530 int rc_exit_on_error_flag)
4531 Run a command.
4533 "rc_exit_on_error_flag" is the "exit_on_error" flag that we pass to the
4535 remote server (when issuing --remote commands). It does not cause
4536 "issue_command" itself to exit on error.
4537 Function "fish/fish.c:extended_help_message"
4539 void
4541 extended_help_message (void)
4542 Print an extended help message when the user types in an unknown
4544 command for the first command issued. A common case is the user doing:
4545 guestfish disk.img
4547 expecting guestfish to open disk.img (in fact, this tried to run a non-
4549 existent command "disk.img").
4550 Function "fish/fish.c:error_cb"
4552 static void
4554 error_cb (guestfs_h *g, void *data, const char *msg)
4555 Error callback. This replaces the standard libguestfs error handler.
4557 Function "fish/fish.c:free_n_strings"
4559 static void
4561 free_n_strings (char **str, size_t len)
4562 Free strings from a non-NULL terminated "char**".
4564 Function "fish/fish.c:decode_ps1"
4566 static char *
4568 decode_ps1 (const char *str)
4569 Decode "str" into the final printable prompt string.
4571 Function "fish/fish.c:win_prefix"
4573 char *
4575 win_prefix (const char *path)
4576 Resolve the special "win:..." form for Windows-specific paths. The
4578 generated code calls this for all device or path arguments.
4579 The function returns a newly allocated string, and the caller must free
4581 this string; else display an error and return "NULL".
4582 Function "fish/fish.c:file_in"
4584 char *
4586 file_in (const char *arg)
4587 Resolve the special "FileIn" paths ("-" or "-<<END" or filename).
4589 The caller (fish/cmds.c) will call "free_file_in" after the command has
4591 run which should clean up resources.
4592 Function "fish/fish.c:file_out"
4594 char *
4596 file_out (const char *arg)
4597 Resolve the special "FileOut" paths ("-" or filename).
4599 The caller (fish/cmds.c) will call "free (str)" after the command has
4601 run.
4602 Function "fish/fish.c:progress_callback"
4604 void
4606 progress_callback (guestfs_h *g, void *data,
4607 uint64_t event, int event_handle, int flags,
4608 const char *buf, size_t buf_len,
4609 const uint64_t *array, size_t array_len)
4610 Callback which displays a progress bar.
4612 File fish/glob.c
4614 This file implements the guestfish "glob" command.
4616 Function "fish/glob.c:expand_devicename"
4618 static char **
4620 expand_devicename (guestfs_h *g, const char *device)
4621 Glob-expand device patterns, such as "/dev/sd*"
4623 (https://bugzilla.redhat.com/635971).
4624 There is no "guestfs_glob_expand_device" function because the
4626 equivalent can be implemented using functions like
4627 "guestfs_list_devices".
4628 It's not immediately clear what it means to expand a pattern like
4630 "/dev/sd*". Should that include device name translation? Should the
4631 result include partitions as well as devices?
4632 Should "/dev/" + "*" return every possible device and filesystem? How
4634 about VGs? LVs?
4635 To solve this what we do is build up a list of every device, partition,
4637 etc., then glob against that list.
4638 Notes for future work (XXX):
4640 • This doesn't handle device name translation. It wouldn't be too
4642 hard to add.
4643 • Could have an API function for returning all device-like things.
4645 Function "fish/glob.c:add_strings_matching"
4647 static int
4649 add_strings_matching (char **pp, const char *glob,
4650 char ***ret, size_t *size_r)
4651 Using POSIX fnmatch(3), find strings in the list "pp" which match
4653 pattern "glob". Add strings which match to the "ret" array. *size_r
4654 is the current size of the "ret" array, which is updated with the new
4655 size.
4656 Function "fish/glob.c:single_element_list"
4658 static char **
4660 single_element_list (const char *element)
4661 Return a single element list containing "element".
4663 File fish/help.c
4665 The file implements the guestfish "help" command.
4667 Function "fish/help.c:display_help"
4669 int
4671 display_help (const char *cmd, size_t argc, char *argv[])
4672 The "help" command.
4674 This used to just list all commands, but that's not very useful.
4676 Instead display some useful context-sensitive help. This could be
4677 improved if we knew how many drives had been added already, and whether
4678 anything was mounted.
4679 File fish/hexedit.c
4681 This file implements the guestfish "hexedit" command.
4683 File fish/lcd.c
4685 Function "fish/lcd.c:run_lcd"
4687 int
4689 run_lcd (const char *cmd, size_t argc, char *argv[])
4690 guestfish "lcd" command (similar to the "lcd" command in BSD ftp).
4692 File fish/man.c
4694 Function "fish/man.c:run_man"
4696 int
4698 run_man (const char *cmd, size_t argc, char *argv[])
4699 guestfish "man" command
4701 File fish/more.c
4703 This file implements the guestfish "more" command.
4705 File fish/prep.c
4707 This file implements the guestfish -N option for creating pre-prepared
4709 disk layouts.
4710 File fish/rc.c
4712 This file implements guestfish remote (command) support.
4714 Function "fish/rc.c:rc_listen"
4716 void
4718 rc_listen (void)
4719 The remote control server (ie. "guestfish --listen").
4721 Function "fish/rc.c:rc_remote"
4723 int
4725 rc_remote (int pid, const char *cmd, size_t argc, char *argv[],
4726 int exit_on_error)
4727 The remote control client (ie. "guestfish --remote").
4729 File fish/reopen.c
4731 This file implements the guestfish "reopen" command.
4733 File fish/setenv.c
4735 This file implements the guestfish "setenv" and "unsetenv" commands.
4737 File fish/supported.c
4739 This file implements the guestfish "supported" command.
4741 File fish/tilde.c
4743 This file implements tilde ("~") expansion of home directories in
4745 guestfish(1).
4746 Function "fish/tilde.c:try_tilde_expansion"
4748 char *
4750 try_tilde_expansion (char *str)
4751 This is called from the script loop if we find a candidate for
4753 "~username" (tilde-expansion).
4754 Function "fish/tilde.c:expand_home"
4756 static char *
4758 expand_home (char *orig, const char *append)
4759 Return $HOME + append string.
4761 Function "fish/tilde.c:find_home_for_username"
4763 static const char *
4765 find_home_for_username (const char *username, size_t ulen)
4766 Lookup "username" (of length "ulen"), return home directory if found,
4768 or "NULL" if not found.
4769 File fish/time.c
4771 This file implements the guestfish "time" command.
4773 Subdirectory python
4775 File python/handle.c
4776 This file contains a small number of functions that are written by
4778 hand. The majority of the bindings are generated (see
4779 python/actions-*.c).
4780
4782 guestfs(3), guestfs-building(1), guestfs-examples(3),
4783 guestfs-internals(1), guestfs-performance(1), guestfs-release-notes(1),
4784 guestfs-testing(1), libguestfs-test-tool(1),
4785 libguestfs-make-fixed-appliance(1), http://libguestfs.org/.
4786
4788 Richard W.M. Jones ("rjones at redhat dot com")
4789
4791 Copyright (C) 2009-2023 Red Hat Inc.
4792
4794 This library is free software; you can redistribute it and/or modify it
4795 under the terms of the GNU Lesser General Public License as published
4796 by the Free Software Foundation; either version 2 of the License, or
4797 (at your option) any later version.
4798 This library is distributed in the hope that it will be useful, but
4800 WITHOUT ANY WARRANTY; without even the implied warranty of
4801 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
4802 Lesser General Public License for more details.
4803 You should have received a copy of the GNU Lesser General Public
4805 License along with this library; if not, write to the Free Software
4806 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
4807 02110-1301 USA
4808
4810 To get a list of bugs against libguestfs, use this link:
4811 https://bugzilla.redhat.com/buglist.cgi?component=libguestfs&product=Virtualization+Tools
4812 To report a new bug against libguestfs, use this link:
4814 https://bugzilla.redhat.com/enter_bug.cgi?component=libguestfs&product=Virtualization+Tools
4815 When reporting a bug, please supply:
4817 • The version of libguestfs.
4819 • Where you got libguestfs (eg. which Linux distro, compiled from
4821 source, etc)
4822 • Describe the bug accurately and give a way to reproduce it.
4824 • Run libguestfs-test-tool(1) and paste the complete, unedited output
4826 into the bug report.
4827libguestfs-1.50.1 2023-02-21 guestfs-hacking(1)