1PCRE(3) Library Functions Manual PCRE(3)
2
6 PCRE - Perl-compatible regular expressions
7 #include <pcre.h>
9
11 pcre32 *pcre32_compile(PCRE_SPTR32 pattern, int options,
13 const char **errptr, int *erroffset,
14 const unsigned char *tableptr);
15 pcre32 *pcre32_compile2(PCRE_SPTR32 pattern, int options,
17 int *errorcodeptr,
18 const char **errptr, int *erroffset,
19 const unsigned char *tableptr);
20 pcre32_extra *pcre32_study(const pcre32 *code, int options,
22 const char **errptr);
23 void pcre32_free_study(pcre32_extra *extra);
25 int pcre32_exec(const pcre32 *code, const pcre32_extra *extra,
27 PCRE_SPTR32 subject, int length, int startoffset,
28 int options, int *ovector, int ovecsize);
29 int pcre32_dfa_exec(const pcre32 *code, const pcre32_extra *extra,
31 PCRE_SPTR32 subject, int length, int startoffset,
32 int options, int *ovector, int ovecsize,
33 int *workspace, int wscount);
34
36 int pcre32_copy_named_substring(const pcre32 *code,
38 PCRE_SPTR32 subject, int *ovector,
39 int stringcount, PCRE_SPTR32 stringname,
40 PCRE_UCHAR32 *buffer, int buffersize);
41 int pcre32_copy_substring(PCRE_SPTR32 subject, int *ovector,
43 int stringcount, int stringnumber, PCRE_UCHAR32 *buffer,
44 int buffersize);
45 int pcre32_get_named_substring(const pcre32 *code,
47 PCRE_SPTR32 subject, int *ovector,
48 int stringcount, PCRE_SPTR32 stringname,
49 PCRE_SPTR32 *stringptr);
50 int pcre32_get_stringnumber(const pcre32 *code,
52 PCRE_SPTR32 name);
53 int pcre32_get_stringtable_entries(const pcre32 *code,
55 PCRE_SPTR32 name, PCRE_UCHAR32 **first, PCRE_UCHAR32 **last);
56 int pcre32_get_substring(PCRE_SPTR32 subject, int *ovector,
58 int stringcount, int stringnumber,
59 PCRE_SPTR32 *stringptr);
60 int pcre32_get_substring_list(PCRE_SPTR32 subject,
62 int *ovector, int stringcount, PCRE_SPTR32 **listptr);
63 void pcre32_free_substring(PCRE_SPTR32 stringptr);
65 void pcre32_free_substring_list(PCRE_SPTR32 *stringptr);
67
69 pcre32_jit_stack *pcre32_jit_stack_alloc(int startsize, int maxsize);
71 void pcre32_jit_stack_free(pcre32_jit_stack *stack);
73 void pcre32_assign_jit_stack(pcre32_extra *extra,
75 pcre32_jit_callback callback, void *data);
76 const unsigned char *pcre32_maketables(void);
78 int pcre32_fullinfo(const pcre32 *code, const pcre32_extra *extra,
80 int what, void *where);
81 int pcre32_refcount(pcre32 *code, int adjust);
83 int pcre32_config(int what, void *where);
85 const char *pcre32_version(void);
87 int pcre32_pattern_to_host_byte_order(pcre32 *code,
89 pcre32_extra *extra, const unsigned char *tables);
90
92 void *(*pcre32_malloc)(size_t);
94 void (*pcre32_free)(void *);
96 void *(*pcre32_stack_malloc)(size_t);
98 void (*pcre32_stack_free)(void *);
100 int (*pcre32_callout)(pcre32_callout_block *);
102
104 int pcre32_utf32_to_host_byte_order(PCRE_UCHAR32 *output,
106 PCRE_SPTR32 input, int length, int *byte_order,
107 int keep_boms);
108
110 Starting with release 8.32, it is possible to compile a PCRE library
112 that supports 32-bit character strings, including UTF-32 strings, as
113 well as or instead of the original 8-bit library. This work was done by
114 Christian Persch, based on the work done by Zoltan Herczeg for the
115 16-bit library. All three libraries contain identical sets of func‐
116 tions, used in exactly the same way. Only the names of the functions
117 and the data types of their arguments and results are different. To
118 avoid over-complication and reduce the documentation maintenance load,
119 most of the PCRE documentation describes the 8-bit library, with only
120 occasional references to the 16-bit and 32-bit libraries. This page
121 describes what is different when you use the 32-bit library.
122 WARNING: A single application can be linked with all or any of the
124 three libraries, but you must take care when processing any particular
125 pattern to use functions from just one library. For example, if you
126 want to study a pattern that was compiled with pcre32_compile(), you
127 must do so with pcre32_study(), not pcre_study(), and you must free the
128 study data with pcre32_free_study().
129
131 There is only one header file, pcre.h. It contains prototypes for all
133 the functions in all libraries, as well as definitions of flags, struc‐
134 tures, error codes, etc.
135
137 In Unix-like systems, the 32-bit library is called libpcre32, and can
139 normally be accesss by adding -lpcre32 to the command for linking an
140 application that uses PCRE.
141
143 In the 8-bit library, strings are passed to PCRE library functions as
145 vectors of bytes with the C type "char *". In the 32-bit library,
146 strings are passed as vectors of unsigned 32-bit quantities. The macro
147 PCRE_UCHAR32 specifies an appropriate data type, and PCRE_SPTR32 is
148 defined as "const PCRE_UCHAR32 *". In very many environments, "unsigned
149 int" is a 32-bit data type. When PCRE is built, it defines PCRE_UCHAR32
150 as "unsigned int", but checks that it really is a 32-bit data type. If
151 it is not, the build fails with an error message telling the maintainer
152 to modify the definition appropriately.
153
155 The types of the opaque structures that are used for compiled 32-bit
157 patterns and JIT stacks are pcre32 and pcre32_jit_stack respectively.
158 The type of the user-accessible structure that is returned by
159 pcre32_study() is pcre32_extra, and the type of the structure that is
160 used for passing data to a callout function is pcre32_callout_block.
161 These structures contain the same fields, with the same names, as their
162 8-bit counterparts. The only difference is that pointers to character
163 strings are 32-bit instead of 8-bit types.
164
166 For every function in the 8-bit library there is a corresponding func‐
168 tion in the 32-bit library with a name that starts with pcre32_ instead
169 of pcre_. The prototypes are listed above. In addition, there is one
170 extra function, pcre32_utf32_to_host_byte_order(). This is a utility
171 function that converts a UTF-32 character string to host byte order if
172 necessary. The other 32-bit functions expect the strings they are
173 passed to be in host byte order.
174 The input and output arguments of pcre32_utf32_to_host_byte_order() may
176 point to the same address, that is, conversion in place is supported.
177 The output buffer must be at least as long as the input.
178 The length argument specifies the number of 32-bit data units in the
180 input string; a negative value specifies a zero-terminated string.
181 If byte_order is NULL, it is assumed that the string starts off in host
183 byte order. This may be changed by byte-order marks (BOMs) anywhere in
184 the string (commonly as the first character).
185 If byte_order is not NULL, a non-zero value of the integer to which it
187 points means that the input starts off in host byte order, otherwise
188 the opposite order is assumed. Again, BOMs in the string can change
189 this. The final byte order is passed back at the end of processing.
190 If keep_boms is not zero, byte-order mark characters (0xfeff) are
192 copied into the output string. Otherwise they are discarded.
193 The result of the function is the number of 32-bit units placed into
195 the output buffer, including the zero terminator if the string was
196 zero-terminated.
197
199 The offsets within subject strings that are returned by the matching
201 functions are in 32-bit units rather than bytes.
202
204 The name-to-number translation table that is maintained for named sub‐
206 patterns uses 32-bit characters. The pcre32_get_stringtable_entries()
207 function returns the length of each entry in the table as the number of
208 32-bit data units.
209
211 There are two new general option names, PCRE_UTF32 and
213 PCRE_NO_UTF32_CHECK, which correspond to PCRE_UTF8 and
214 PCRE_NO_UTF8_CHECK in the 8-bit library. In fact, these new options
215 define the same bits in the options word. There is a discussion about
216 the validity of UTF-32 strings in the pcreunicode page.
217 For the pcre32_config() function there is an option PCRE_CONFIG_UTF32
219 that returns 1 if UTF-32 support is configured, otherwise 0. If this
220 option is given to pcre_config() or pcre16_config(), or if the
221 PCRE_CONFIG_UTF8 or PCRE_CONFIG_UTF16 option is given to pcre32_con‐
222 fig(), the result is the PCRE_ERROR_BADOPTION error.
223
225 In 32-bit mode, when PCRE_UTF32 is not set, character values are
227 treated in the same way as in 8-bit, non UTF-8 mode, except, of course,
228 that they can range from 0 to 0x7fffffff instead of 0 to 0xff. Charac‐
229 ter types for characters less than 0xff can therefore be influenced by
230 the locale in the same way as before. Characters greater than 0xff
231 have only one case, and no "type" (such as letter or digit).
232 In UTF-32 mode, the character code is Unicode, in the range 0 to
234 0x10ffff, with the exception of values in the range 0xd800 to 0xdfff
235 because those are "surrogate" values that are ill-formed in UTF-32.
236 A UTF-32 string can indicate its endianness by special code knows as a
238 byte-order mark (BOM). The PCRE functions do not handle this, expecting
239 strings to be in host byte order. A utility function called
240 pcre32_utf32_to_host_byte_order() is provided to help with this (see
241 above).
242
244 The error PCRE_ERROR_BADUTF32 corresponds to its 8-bit counterpart.
246 The error PCRE_ERROR_BADMODE is given when a compiled pattern is passed
247 to a function that processes patterns in the other mode, for example,
248 if a pattern compiled with pcre_compile() is passed to pcre32_exec().
249 There are new error codes whose names begin with PCRE_UTF32_ERR for
251 invalid UTF-32 strings, corresponding to the PCRE_UTF8_ERR codes for
252 UTF-8 strings that are described in the section entitled "Reason codes
253 for invalid UTF-8 strings" in the main pcreapi page. The UTF-32 errors
254 are:
255 PCRE_UTF32_ERR1 Surrogate character (range from 0xd800 to 0xdfff)
257 PCRE_UTF32_ERR2 Non-character
258 PCRE_UTF32_ERR3 Character > 0x10ffff
259
261 If there is an error while compiling a pattern, the error text that is
263 passed back by pcre32_compile() or pcre32_compile2() is still an 8-bit
264 character string, zero-terminated.
265
267 The subject and mark fields in the callout block that is passed to a
269 callout function point to 32-bit vectors.
270
272 The pcretest program continues to operate with 8-bit input and output
274 files, but it can be used for testing the 32-bit library. If it is run
275 with the command line option -32, patterns and subject strings are con‐
276 verted from 8-bit to 32-bit before being passed to PCRE, and the 32-bit
277 library functions are used instead of the 8-bit ones. Returned 32-bit
278 strings are converted to 8-bit for output. If both the 8-bit and the
279 16-bit libraries were not compiled, pcretest defaults to 32-bit and the
280 -32 option is ignored.
281 When PCRE is being built, the RunTest script that is called by "make
283 check" uses the pcretest -C option to discover which of the 8-bit,
284 16-bit and 32-bit libraries has been built, and runs the tests appro‐
285 priately.
286
288 Not all the features of the 8-bit library are available with the 32-bit
290 library. The C++ and POSIX wrapper functions support only the 8-bit
291 library, and the pcregrep program is at present 8-bit only.
292
294 Philip Hazel
296 University Computing Service
297 Cambridge CB2 3QH, England.
298
300 Last updated: 08 November 2012
302 Copyright (c) 1997-2012 University of Cambridge.
303PCRE 8.32 08 November 2012 PCRE(3)