1METALINK_PARSE_UPDATE(3) libmetalink Manual METALINK_PARSE_UPDATE(3)
2
6 metalink_parse_update, metalink_parse_final, metalink_parser_con‐
7 text_new, metalink_parser_context_delete - Parse Metalink file and cre‐
8 ate metalink_t object.
9
12 #include <metalink/metalink.h>
13 metalink_error_t metalink_parse_update(metalink_parser_context_t *ctx,
15 const char *buf, size_t len);
16 metalink_error_t metalink_parse_final(metalink_parser_context_t *ctx,
17 const char *buf, size_t len,
18 metalink_t **res);
19 metalink_parser_context_t* metalink_parser_context_new();
21 void metalink_parser_context_delete(metalink_parser_context_t *ctx);
22
25 These functions provide a push interface for parsing Metalink XML
26 files.
27 Before calling metalink_parse_update() and metalink_parse_final(), met‐
29 alink_parse_context_t has to be created by metalink_parser_con‐
30 text_new().
31 In each call of metalink_parse_update(), len bytes of buf are pro‐
33 cessed. At the last piece of data, call metalink_parse_final() to get
34 metalink_t(3) structure as a result. Giving 0 as len is permitted.
35 metalink_parse_final() calls metalink_parser_context_delete() inter‐
37 nally to deallocate the memory for passed metalink_parser_context_t.
38 Therefore you don't have to call metlaink_parser_context_delete() if
39 you call metalink_parse_final(). Otherwise call metalink_parser_con‐
40 text_delete() to free the allocated resource.
41 You don't have to allocate memory for metalink_t(3) structure. met‐
43 alink_parse_final() takes the pointer of metalink_t(3) pointer and
44 allocates memory for that pointer.
45 The caller must free the memory allocated for metalink_t(3) structure
47 using metalink_delete(3) if it is no longer used.
48
51 metalink_parse_update(), metalink_parse_final() return 0 for success.
52 When error occurred, non-zero value error code is returned. If error
53 occurred, metalink_parse_final() does not allocate memory for met‐
54 alink_t. The error codes are described in metalink_error.h.
55 In case of success, metalink_parser_context_new() allocates memory for
57 metalink_parser_context_t() and returns the pointer to it. In case of
58 failure, metalink_parser_context_new() returns NULL.
59 metalink_parser_context_delete() returns no value.
61
64 #include <stdio.h>
65 #include <stdlib.h>
66 #include <sys/types.h>
67 #include <sys/stat.h>
68 #include <fcntl.h>
69 #include <errno.h>
70 #include <string.h>
71 #include <unistd.h>
72 #include <metalink/metalink.h>
73 int main(int argc, char** argv)
75 {
76 metalink_error_t r;
77 metalink_t* metalink;
78 metalink_file_t* file;
79 metalink_checksum_t** checksums;
80 metalink_parser_context_t* context;
81 int fd;
82 char buf[BUFSIZ];
83 ssize_t length;
84 context = metalink_parser_context_new();
86 if(context == NULL) {
88 fprintf(stderr,
89 "ERROR: failed to create metalink_parser_context_t\n");
90 exit(EXIT_FAILURE);
91 }
92 fd = open("sample.metalink", O_RDONLY);
94 if(fd == -1) {
95 fprintf(stderr, "ERROR: open():%s\n", strerror(errno));
96 exit(EXIT_FAILURE);
97 }
98 while((length = TEMP_FAILURE_RETRY(read(fd, buf, sizeof(buf)))) != 0){
99 r = metalink_parse_update(context, buf, length);
100 if(r != 0) {
101 fprintf(stderr, "ERROR: code=%d\n", r);
102 metalink_parser_context_delete(context);
103 exit(EXIT_FAILURE);
104 }
105 }
106 if(length == -1) {
107 fprintf(stderr, "ERROR: read():%s\n", strerror(errno));
108 metalink_parser_context_delete(context);
109 exit(EXIT_FAILURE);
110 }
111 r = metalink_parse_final(context, NULL, 0, &metalink);
113 if(r != 0) {
115 fprintf(stderr, "ERROR: code=%d\n", r);
116 exit(EXIT_FAILURE);
117 }
118 TEMP_FAILURE_RETRY(close(fd));
120 file = metalink->files[0];
122 printf("name: %s\n", file->name);
123 printf("size: %lld\n", file->size);
124 printf("os : %s\n", file->os);
125 if(file->checksums) {
127 checksums = file->checksums;
128 while(*checksums) {
129 printf("hash: %s %s\n", (*checksums)->type, (*checksums)->hash);
130 ++checksums;
131 }
132 }
133 if(file->chunk_checksum) {
134 size_t count = 0;
135 metalink_piece_hash_t** piece_hashes;
136 printf("chunk checksum: size=%d, type=%s\n",
137 file->chunk_checksum->length,
138 file->chunk_checksum->type);
139 printf("first 5 piece hashes...\n");
140 piece_hashes = file->chunk_checksum->piece_hashes;
141 while(*piece_hashes && count < 5) {
142 printf("piece=%d, hash=%s\n", (*piece_hashes)->piece,
143 (*piece_hashes)->hash);
144 ++piece_hashes;
145 ++count;
146 }
147 printf("...\n");
148 }
149 if(file->resources) {
150 size_t count = 0;
151 metalink_resource_t** resources;
152 printf("first 5 resources...\n");
153 resources = file->resources;
154 while(*resources && count < 5) {
155 printf("type=%s, location=%s, preference=%d, url=%s\n",
156 (*resources)->type, (*resources)->location,
157 (*resources)->preference, (*resources)->url);
158 ++resources;
159 ++count;
160 }
161 printf("...\n");
162 }
163 /* delete metalink_t */
165 metalink_delete(metalink);
166 return EXIT_SUCCESS;
168 }
169
172 metalink_delete(3), metalink_parse_file(3), metalink_t(3)
173libmetalink 0.1.0 July 2012 METALINK_PARSE_UPDATE(3)