fix bug with fractional seconds on some locales (SF#1858012: https://sourceforge...
[flac.git] / src / flac / vorbiscomment.c
1 /* flac - Command-line FLAC encoder/decoder
2  * Copyright (C) 2002,2003,2004,2005,2006,2007,2008  Josh Coalson
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License
6  * as published by the Free Software Foundation; either version 2
7  * of the License, or (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
17  */
18
19 #if HAVE_CONFIG_H
20 #  include <config.h>
21 #endif
22
23 #include "vorbiscomment.h"
24 #include "FLAC/assert.h"
25 #include "FLAC/metadata.h"
26 #include "share/grabbag.h" /* for grabbag__file_get_filesize() */
27 #include "share/utf8.h"
28 #include <ctype.h>
29 #include <stdio.h>
30 #include <stdlib.h>
31 #include <string.h>
32
33
34 /*
35  * This struct and the following 4 static functions are copied from
36  * ../metaflac/.  Maybe someday there will be a convenience
37  * library for Vorbis comment parsing.
38  */
39 typedef struct {
40         char *field; /* the whole field as passed on the command line, i.e. "NAME=VALUE" */
41         char *field_name;
42         /* according to the vorbis spec, field values can contain \0 so simple C strings are not enough here */
43         unsigned field_value_length;
44         char *field_value;
45         FLAC__bool field_value_from_file; /* true if field_value holds a filename for the value, false for plain value */
46 } Argument_VcField;
47
48 static void die(const char *message)
49 {
50         FLAC__ASSERT(0 != message);
51         fprintf(stderr, "ERROR: %s\n", message);
52         exit(1);
53 }
54
55 static char *local_strdup(const char *source)
56 {
57         char *ret;
58         FLAC__ASSERT(0 != source);
59         if(0 == (ret = strdup(source)))
60                 die("out of memory during strdup()");
61         return ret;
62 }
63
64 static FLAC__bool parse_vorbis_comment_field(const char *field_ref, char **field, char **name, char **value, unsigned *length, const char **violation)
65 {
66         static const char * const violations[] = {
67                 "field name contains invalid character",
68                 "field contains no '=' character"
69         };
70
71         char *p, *q, *s;
72
73         if(0 != field)
74                 *field = local_strdup(field_ref);
75
76         s = local_strdup(field_ref);
77
78         if(0 == (p = strchr(s, '='))) {
79                 free(s);
80                 *violation = violations[1];
81                 return false;
82         }
83         *p++ = '\0';
84
85         for(q = s; *q; q++) {
86                 if(*q < 0x20 || *q > 0x7d || *q == 0x3d) {
87                         free(s);
88                         *violation = violations[0];
89                         return false;
90                 }
91         }
92
93         *name = local_strdup(s);
94         *value = local_strdup(p);
95         *length = strlen(p);
96
97         free(s);
98         return true;
99 }
100
101 /* slight modification: no 'filename' arg, and errors are passed back in 'violation' instead of printed to stderr */
102 static FLAC__bool set_vc_field(FLAC__StreamMetadata *block, const Argument_VcField *field, FLAC__bool *needs_write, FLAC__bool raw, const char **violation)
103 {
104         FLAC__StreamMetadata_VorbisComment_Entry entry;
105         char *converted;
106
107         FLAC__ASSERT(0 != block);
108         FLAC__ASSERT(block->type == FLAC__METADATA_TYPE_VORBIS_COMMENT);
109         FLAC__ASSERT(0 != field);
110         FLAC__ASSERT(0 != needs_write);
111
112         if(field->field_value_from_file) {
113                 /* read the file into 'data' */
114                 FILE *f = 0;
115                 char *data = 0;
116                 const off_t size = grabbag__file_get_filesize(field->field_value);
117                 if(size < 0) {
118                         *violation = "can't open file for tag value";
119                         return false;
120                 }
121                 if(size >= 0x100000) { /* magic arbitrary limit, actual format limit is near 16MB */
122                         *violation = "file for tag value is too large";
123                         return false;
124                 }
125                 if(0 == (data = malloc(size+1)))
126                         die("out of memory allocating tag value");
127                 data[size] = '\0';
128                 if(0 == (f = fopen(field->field_value, "rb")) || fread(data, 1, size, f) != (size_t)size) {
129                         free(data);
130                         if(f)
131                                 fclose(f);
132                         *violation = "error while reading file for tag value";
133                         return false;
134                 }
135                 fclose(f);
136                 if(strlen(data) != (size_t)size) {
137                         free(data);
138                         *violation = "file for tag value has embedded NULs";
139                         return false;
140                 }
141
142                 /* move 'data' into 'converted', converting to UTF-8 if necessary */
143                 if(raw) {
144                         converted = data;
145                 }
146                 else if(utf8_encode(data, &converted) >= 0) {
147                         free(data);
148                 }
149                 else {
150                         free(data);
151                         *violation = "error converting file contents to UTF-8 for tag value";
152                         return false;
153                 }
154
155                 /* create and entry and append it */
156                 if(!FLAC__metadata_object_vorbiscomment_entry_from_name_value_pair(&entry, field->field_name, converted)) {
157                         free(converted);
158                         *violation = "file for tag value is not valid UTF-8";
159                         return false;
160                 }
161                 free(converted);
162                 if(!FLAC__metadata_object_vorbiscomment_append_comment(block, entry, /*copy=*/false)) {
163                         *violation = "memory allocation failure";
164                         return false;
165                 }
166
167                 *needs_write = true;
168                 return true;
169         }
170         else {
171                 FLAC__bool needs_free = false;
172                 if(raw) {
173                         entry.entry = (FLAC__byte *)field->field;
174                 }
175                 else if(utf8_encode(field->field, &converted) >= 0) {
176                         entry.entry = (FLAC__byte *)converted;
177                         needs_free = true;
178                 }
179                 else {
180                         *violation = "error converting comment to UTF-8";
181                         return false;
182                 }
183                 entry.length = strlen((const char *)entry.entry);
184                 if(!FLAC__format_vorbiscomment_entry_is_legal(entry.entry, entry.length)) {
185                         if(needs_free)
186                                 free(converted);
187                         /*
188                          * our previous parsing has already established that the field
189                          * name is OK, so it must be the field value
190                          */
191                         *violation = "tag value for is not valid UTF-8";
192                         return false;
193                 }
194
195                 if(!FLAC__metadata_object_vorbiscomment_append_comment(block, entry, /*copy=*/true)) {
196                         if(needs_free)
197                                 free(converted);
198                         *violation = "memory allocation failure";
199                         return false;
200                 }
201
202                 *needs_write = true;
203                 if(needs_free)
204                         free(converted);
205                 return true;
206         }
207 }
208
209 /*
210  * The rest of the code is novel
211  */
212
213 static void free_field(Argument_VcField *obj)
214 {
215         if(0 != obj->field)
216                 free(obj->field);
217         if(0 != obj->field_name)
218                 free(obj->field_name);
219         if(0 != obj->field_value)
220                 free(obj->field_value);
221 }
222
223 FLAC__bool flac__vorbiscomment_add(FLAC__StreamMetadata *block, const char *comment, FLAC__bool value_from_file, FLAC__bool raw, const char **violation)
224 {
225         Argument_VcField parsed;
226         FLAC__bool dummy;
227
228         FLAC__ASSERT(0 != block);
229         FLAC__ASSERT(block->type == FLAC__METADATA_TYPE_VORBIS_COMMENT);
230         FLAC__ASSERT(0 != comment);
231
232         memset(&parsed, 0, sizeof(parsed));
233
234         parsed.field_value_from_file = value_from_file;
235         if(!parse_vorbis_comment_field(comment, &(parsed.field), &(parsed.field_name), &(parsed.field_value), &(parsed.field_value_length), violation)) {
236                 free_field(&parsed);
237                 return false;
238         }
239
240         if(!set_vc_field(block, &parsed, &dummy, raw, violation)) {
241                 free_field(&parsed);
242                 return false;
243         }
244         else {
245                 free_field(&parsed);
246                 return true;
247         }
248 }