FFmpeg
dict.c
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1 /*
2  * copyright (c) 2009 Michael Niedermayer
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #include <string.h>
22 
23 #include "avstring.h"
24 #include "dict.h"
25 #include "internal.h"
26 #include "mem.h"
27 #include "time_internal.h"
28 #include "bprint.h"
29 
30 struct AVDictionary {
31  int count;
32  AVDictionaryEntry *elems;
33 };
34 
35 int av_dict_count(const AVDictionary *m)
36 {
37  return m ? m->count : 0;
38 }
39 
40 AVDictionaryEntry *av_dict_get(const AVDictionary *m, const char *key,
41  const AVDictionaryEntry *prev, int flags)
42 {
43  unsigned int i, j;
44 
45  if (!m)
46  return NULL;
47 
48  if (prev)
49  i = prev - m->elems + 1;
50  else
51  i = 0;
52 
53  for (; i < m->count; i++) {
54  const char *s = m->elems[i].key;
55  if (flags & AV_DICT_MATCH_CASE)
56  for (j = 0; s[j] == key[j] && key[j]; j++)
57  ;
58  else
59  for (j = 0; av_toupper(s[j]) == av_toupper(key[j]) && key[j]; j++)
60  ;
61  if (key[j])
62  continue;
63  if (s[j] && !(flags & AV_DICT_IGNORE_SUFFIX))
64  continue;
65  return &m->elems[i];
66  }
67  return NULL;
68 }
69 
70 int av_dict_set(AVDictionary **pm, const char *key, const char *value,
71  int flags)
72 {
73  AVDictionary *m = *pm;
74  AVDictionaryEntry *tag = NULL;
75  char *oldval = NULL, *copy_key = NULL, *copy_value = NULL;
76 
77  if (!(flags & AV_DICT_MULTIKEY)) {
78  tag = av_dict_get(m, key, NULL, flags);
79  }
80  if (flags & AV_DICT_DONT_STRDUP_KEY)
81  copy_key = (void *)key;
82  else
83  copy_key = av_strdup(key);
84  if (flags & AV_DICT_DONT_STRDUP_VAL)
85  copy_value = (void *)value;
86  else if (copy_key)
87  copy_value = av_strdup(value);
88  if (!m)
89  m = *pm = av_mallocz(sizeof(*m));
90  if (!m || (key && !copy_key) || (value && !copy_value))
91  goto err_out;
92 
93  if (tag) {
94  if (flags & AV_DICT_DONT_OVERWRITE) {
95  av_free(copy_key);
96  av_free(copy_value);
97  return 0;
98  }
99  if (flags & AV_DICT_APPEND)
100  oldval = tag->value;
101  else
102  av_free(tag->value);
103  av_free(tag->key);
104  *tag = m->elems[--m->count];
105  } else if (copy_value) {
106  AVDictionaryEntry *tmp = av_realloc_array(m->elems,
107  m->count + 1, sizeof(*m->elems));
108  if (!tmp)
109  goto err_out;
110  m->elems = tmp;
111  }
112  if (copy_value) {
113  m->elems[m->count].key = copy_key;
114  m->elems[m->count].value = copy_value;
115  if (oldval && flags & AV_DICT_APPEND) {
116  size_t len = strlen(oldval) + strlen(copy_value) + 1;
117  char *newval = av_mallocz(len);
118  if (!newval)
119  goto err_out;
120  av_strlcat(newval, oldval, len);
121  av_freep(&oldval);
122  av_strlcat(newval, copy_value, len);
123  m->elems[m->count].value = newval;
124  av_freep(&copy_value);
125  }
126  m->count++;
127  } else {
128  av_freep(&copy_key);
129  }
130  if (!m->count) {
131  av_freep(&m->elems);
132  av_freep(pm);
133  }
134 
135  return 0;
136 
137 err_out:
138  if (m && !m->count) {
139  av_freep(&m->elems);
140  av_freep(pm);
141  }
142  av_free(copy_key);
143  av_free(copy_value);
144  return AVERROR(ENOMEM);
145 }
146 
147 int av_dict_set_int(AVDictionary **pm, const char *key, int64_t value,
148  int flags)
149 {
150  char valuestr[22];
151  snprintf(valuestr, sizeof(valuestr), "%"PRId64, value);
152  flags &= ~AV_DICT_DONT_STRDUP_VAL;
153  return av_dict_set(pm, key, valuestr, flags);
154 }
155 
156 static int parse_key_value_pair(AVDictionary **pm, const char **buf,
157  const char *key_val_sep, const char *pairs_sep,
158  int flags)
159 {
160  char *key = av_get_token(buf, key_val_sep);
161  char *val = NULL;
162  int ret;
163 
164  if (key && *key && strspn(*buf, key_val_sep)) {
165  (*buf)++;
166  val = av_get_token(buf, pairs_sep);
167  }
168 
169  if (key && *key && val && *val)
170  ret = av_dict_set(pm, key, val, flags);
171  else
172  ret = AVERROR(EINVAL);
173 
174  av_freep(&key);
175  av_freep(&val);
176 
177  return ret;
178 }
179 
180 int av_dict_parse_string(AVDictionary **pm, const char *str,
181  const char *key_val_sep, const char *pairs_sep,
182  int flags)
183 {
184  int ret;
185 
186  if (!str)
187  return 0;
188 
189  /* ignore STRDUP flags */
190  flags &= ~(AV_DICT_DONT_STRDUP_KEY | AV_DICT_DONT_STRDUP_VAL);
191 
192  while (*str) {
193  if ((ret = parse_key_value_pair(pm, &str, key_val_sep, pairs_sep, flags)) < 0)
194  return ret;
195 
196  if (*str)
197  str++;
198  }
199 
200  return 0;
201 }
202 
203 void av_dict_free(AVDictionary **pm)
204 {
205  AVDictionary *m = *pm;
206 
207  if (m) {
208  while (m->count--) {
209  av_freep(&m->elems[m->count].key);
210  av_freep(&m->elems[m->count].value);
211  }
212  av_freep(&m->elems);
213  }
214  av_freep(pm);
215 }
216 
217 int av_dict_copy(AVDictionary **dst, const AVDictionary *src, int flags)
218 {
219  AVDictionaryEntry *t = NULL;
220 
221  while ((t = av_dict_get(src, "", t, AV_DICT_IGNORE_SUFFIX))) {
222  int ret = av_dict_set(dst, t->key, t->value, flags);
223  if (ret < 0)
224  return ret;
225  }
226 
227  return 0;
228 }
229 
230 int av_dict_get_string(const AVDictionary *m, char **buffer,
231  const char key_val_sep, const char pairs_sep)
232 {
233  AVDictionaryEntry *t = NULL;
234  AVBPrint bprint;
235  int cnt = 0;
236  char special_chars[] = {pairs_sep, key_val_sep, '\0'};
237 
238  if (!buffer || pairs_sep == '\0' || key_val_sep == '\0' || pairs_sep == key_val_sep ||
239  pairs_sep == '\\' || key_val_sep == '\\')
240  return AVERROR(EINVAL);
241 
242  if (!av_dict_count(m)) {
243  *buffer = av_strdup("");
244  return *buffer ? 0 : AVERROR(ENOMEM);
245  }
246 
247  av_bprint_init(&bprint, 64, AV_BPRINT_SIZE_UNLIMITED);
248  while ((t = av_dict_get(m, "", t, AV_DICT_IGNORE_SUFFIX))) {
249  if (cnt++)
250  av_bprint_append_data(&bprint, &pairs_sep, 1);
251  av_bprint_escape(&bprint, t->key, special_chars, AV_ESCAPE_MODE_BACKSLASH, 0);
252  av_bprint_append_data(&bprint, &key_val_sep, 1);
253  av_bprint_escape(&bprint, t->value, special_chars, AV_ESCAPE_MODE_BACKSLASH, 0);
254  }
255  return av_bprint_finalize(&bprint, buffer);
256 }
257 
258 int avpriv_dict_set_timestamp(AVDictionary **dict, const char *key, int64_t timestamp)
259 {
260  time_t seconds = timestamp / 1000000;
261  struct tm *ptm, tmbuf;
262  ptm = gmtime_r(&seconds, &tmbuf);
263  if (ptm) {
264  char buf[32];
265  if (!strftime(buf, sizeof(buf), "%Y-%m-%dT%H:%M:%S", ptm))
266  return AVERROR_EXTERNAL;
267  av_strlcatf(buf, sizeof(buf), ".%06dZ", (int)(timestamp % 1000000));
268  return av_dict_set(dict, key, buf, 0);
269  } else {
270  return AVERROR_EXTERNAL;
271  }
272 }
AV_BPRINT_SIZE_UNLIMITED
#define AV_BPRINT_SIZE_UNLIMITED
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
av_bprint_finalize
int av_bprint_finalize(AVBPrint *buf, char **ret_str)
Finalize a print buffer.
Definition: bprint.c:235
av_bprint_init
void av_bprint_init(AVBPrint *buf, unsigned size_init, unsigned size_max)
Definition: bprint.c:69
av_get_token
char * av_get_token(const char **buf, const char *term)
Unescape the given string until a non escaped terminating char, and return the token corresponding to...
Definition: avstring.c:151
av_dict_count
int av_dict_count(const AVDictionary *m)
Get number of entries in dictionary.
Definition: dict.c:35
AVDictionary::elems
AVDictionaryEntry * elems
Definition: dict.c:32
tmp
static uint8_t tmp[11]
Definition: aes_ctr.c:27
AV_DICT_APPEND
#define AV_DICT_APPEND
If the entry already exists, append to it.
Definition: dict.h:77
AV_DICT_IGNORE_SUFFIX
#define AV_DICT_IGNORE_SUFFIX
Return first entry in a dictionary whose first part corresponds to the search key,...
Definition: dict.h:70
AVDictionary
Definition: dict.c:30
av_bprint_append_data
void av_bprint_append_data(AVBPrint *buf, const char *data, unsigned size)
Append data to a print buffer.
Definition: bprint.c:158
av_strlcatf
size_t av_strlcatf(char *dst, size_t size, const char *fmt,...)
Definition: avstring.c:101
gmtime_r
#define gmtime_r
Definition: time_internal.h:34
val
static double val(void *priv, double ch)
Definition: aeval.c:76
AV_DICT_DONT_STRDUP_VAL
#define AV_DICT_DONT_STRDUP_VAL
Take ownership of a value that's been allocated with av_malloc() or another memory allocation functio...
Definition: dict.h:74
av_dict_get
AVDictionaryEntry * av_dict_get(const AVDictionary *m, const char *key, const AVDictionaryEntry *prev, int flags)
Get a dictionary entry with matching key.
Definition: dict.c:40
s
#define s(width, name)
Definition: cbs_vp9.c:257
av_realloc_array
void * av_realloc_array(void *ptr, size_t nmemb, size_t size)
Definition: mem.c:205
AVDictionaryEntry::key
char * key
Definition: dict.h:82
key
const char * key
Definition: hwcontext_opencl.c:168
time_internal.h
AVDictionary::count
int count
Definition: dict.c:31
NULL
#define NULL
Definition: coverity.c:32
AV_DICT_MULTIKEY
#define AV_DICT_MULTIKEY
Allow to store several equal keys in the dictionary.
Definition: dict.h:79
src
#define src
Definition: vp8dsp.c:255
AV_DICT_DONT_OVERWRITE
#define AV_DICT_DONT_OVERWRITE
Don't overwrite existing entries.
Definition: dict.h:76
AVERROR_EXTERNAL
#define AVERROR_EXTERNAL
Generic error in an external library.
Definition: error.h:57
av_dict_free
void av_dict_free(AVDictionary **pm)
Free all the memory allocated for an AVDictionary struct and all keys and values.
Definition: dict.c:203
bprint.h
i
int i
Definition: input.c:407
parse_key_value_pair
static int parse_key_value_pair(AVDictionary **pm, const char **buf, const char *key_val_sep, const char *pairs_sep, int flags)
Definition: dict.c:156
internal.h
value
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf default value
Definition: writing_filters.txt:86
av_toupper
static av_const int av_toupper(int c)
Locale-independent conversion of ASCII characters to uppercase.
Definition: avstring.h:236
av_mallocz
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:244
len
int len
Definition: vorbis_enc_data.h:426
tag
uint32_t tag
Definition: movenc.c:1594
ret
ret
Definition: filter_design.txt:187
av_strlcat
size_t av_strlcat(char *dst, const char *src, size_t size)
Append the string src to the string dst, but to a total length of no more than size - 1 bytes,...
Definition: avstring.c:93
dict.h
av_bprint_escape
void av_bprint_escape(AVBPrint *dstbuf, const char *src, const char *special_chars, enum AVEscapeMode mode, int flags)
Escape the content in src and append it to dstbuf.
Definition: bprint.c:265
AV_DICT_MATCH_CASE
#define AV_DICT_MATCH_CASE
Only get an entry with exact-case key match.
Definition: dict.h:69
buffer
the frame and frame reference mechanism is intended to as much as expensive copies of that data while still allowing the filters to produce correct results The data is stored in buffers represented by AVFrame structures Several references can point to the same frame buffer
Definition: filter_design.txt:49
av_dict_parse_string
int av_dict_parse_string(AVDictionary **pm, const char *str, const char *key_val_sep, const char *pairs_sep, int flags)
Parse the key/value pairs list and add the parsed entries to a dictionary.
Definition: dict.c:180
av_dict_set_int
int av_dict_set_int(AVDictionary **pm, const char *key, int64_t value, int flags)
Convenience wrapper for av_dict_set that converts the value to a string and stores it.
Definition: dict.c:147
av_strdup
char * av_strdup(const char *s)
Duplicate a string.
Definition: mem.c:260
mem.h
av_free
#define av_free(p)
Definition: tableprint_vlc.h:34
AVDictionaryEntry
Definition: dict.h:81
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:35
av_dict_set
int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags)
Set the given entry in *pm, overwriting an existing entry.
Definition: dict.c:70
av_dict_get_string
int av_dict_get_string(const AVDictionary *m, char **buffer, const char key_val_sep, const char pairs_sep)
Get dictionary entries as a string.
Definition: dict.c:230
av_dict_copy
int av_dict_copy(AVDictionary **dst, const AVDictionary *src, int flags)
Copy entries from one AVDictionary struct into another.
Definition: dict.c:217
AV_ESCAPE_MODE_BACKSLASH
@ AV_ESCAPE_MODE_BACKSLASH
Use backslash escaping.
Definition: avstring.h:325
convert_header.str
string str
Definition: convert_header.py:20
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
AVDictionaryEntry::value
char * value
Definition: dict.h:83
avstring.h
snprintf
#define snprintf
Definition: snprintf.h:34
avpriv_dict_set_timestamp
int avpriv_dict_set_timestamp(AVDictionary **dict, const char *key, int64_t timestamp)
Set a dictionary value to an ISO-8601 compliant timestamp string.
Definition: dict.c:258
AV_DICT_DONT_STRDUP_KEY
#define AV_DICT_DONT_STRDUP_KEY
Take ownership of a key that's been allocated with av_malloc() or another memory allocation function.
Definition: dict.h:72
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