Asterisk - The Open Source Telephony Project  21.4.1
file.h
Go to the documentation of this file.
1 /*
2  * Asterisk -- An open source telephony toolkit.
3  *
4  * Copyright (C) 1999 - 2006, Digium, Inc.
5  *
6  * Mark Spencer <markster@digium.com>
7  *
8  * See http://www.asterisk.org for more information about
9  * the Asterisk project. Please do not directly contact
10  * any of the maintainers of this project for assistance;
11  * the project provides a web site, mailing lists and IRC
12  * channels for your use.
13  *
14  * This program is free software, distributed under the terms of
15  * the GNU General Public License Version 2. See the LICENSE file
16  * at the top of the source tree.
17  */
18 
19 /*! \file
20  * \brief Generic File Format Support.
21  * Should be included by clients of the file handling routines.
22  * File service providers should instead include mod_format.h
23  */
24 
25 #ifndef _ASTERISK_FILE_H
26 #define _ASTERISK_FILE_H
27 
28 #ifdef HAVE_FCNTL_H
29 #include <fcntl.h>
30 #endif
31 
32 #ifdef HAVE_MMAP
33 #include <sys/mman.h>
34 #endif
35 
36 #if defined(__cplusplus) || defined(c_plusplus)
37 extern "C" {
38 #endif
39 
40 struct ast_filestream;
41 struct ast_format;
42 
43 /*! The maximum number of formats we expect to see in a format string */
44 #define AST_MAX_FORMATS 10
45 
46 /*! Convenient for waiting */
47 #define AST_DIGIT_NONE ""
48 #define AST_DIGIT_ANY "0123456789#*ABCD"
49 #define AST_DIGIT_ANYNUM "0123456789"
50 
51 #define SEEK_FORCECUR 10
52 
53 /*! The type of event associated with a ast_waitstream_fr_cb invocation */
55  AST_WAITSTREAM_CB_REWIND = 1,
56  AST_WAITSTREAM_CB_FASTFORWARD,
57  AST_WAITSTREAM_CB_START
58 };
59 
60 /*!
61  * \brief callback used during dtmf controlled file playback to indicate
62  * location of playback in a file after rewinding or fastforwarding
63  * a file.
64  */
65 typedef void (ast_waitstream_fr_cb)(struct ast_channel *chan, long ms, enum ast_waitstream_fr_cb_values val);
66 
67 /*!
68  * \brief Streams a file
69  * \param c channel to stream the file to
70  * \param filename the name of the file you wish to stream, minus the extension
71  * \param preflang the preferred language you wish to have the file streamed to you in
72  * Prepares a channel for the streaming of a file. To start the stream, afterward do a ast_waitstream() on the channel
73  * Also, it will stop any existing streams on the channel.
74  * \retval 0 on success.
75  * \retval -1 on failure.
76  */
77 int ast_streamfile(struct ast_channel *c, const char *filename, const char *preflang);
78 
79 /*!
80  * \brief stream file until digit
81  * If the file name is non-empty, try to play it.
82  * \note If digits == "" then we can simply check for non-zero.
83  * \note If a failure is encountered, the stream will be closed before returning.
84  * \retval 0 if success.
85  * \retval -1 if error.
86  * \retval digit if interrupted by a digit.
87  */
88 int ast_stream_and_wait(struct ast_channel *chan, const char *file, const char *digits);
89 
90 /*!
91  * \brief Stops a stream
92  *
93  * \param c The channel you wish to stop playback on
94  *
95  * Stop playback of a stream
96  *
97  * \retval 0 always
98  *
99  * \note The channel does not need to be locked before calling this function.
100  */
101 int ast_stopstream(struct ast_channel *c);
102 
103 /*!
104  * \brief Checks for the existence of a given file
105  * \param filename name of the file you wish to check, minus the extension
106  * \param fmt the format you wish to check (the extension)
107  * \param preflang (the preferred language you wisht to find the file in)
108  * See if a given file exists in a given format. If fmt is NULL, any format is accepted.
109  * \retval 0 The file does not exist
110  * \retval 1 The file does exist.
111  */
112 int ast_fileexists(const char *filename, const char *fmt, const char *preflang);
113 
114 /*!
115  * \brief Renames a file
116  * \param oldname the name of the file you wish to act upon (minus the extension)
117  * \param newname the name you wish to rename the file to (minus the extension)
118  * \param fmt the format of the file
119  * Rename a given file in a given format, or if fmt is NULL, then do so for all
120  * \retval -1 on failure
121  */
122 int ast_filerename(const char *oldname, const char *newname, const char *fmt);
123 
124 /*!
125  * \brief Deletes a file
126  * \param filename name of the file you wish to delete (minus the extension)
127  * \param fmt of the file
128  * Delete a given file in a given format, or if fmt is NULL, then do so for all
129  */
130 int ast_filedelete(const char *filename, const char *fmt);
131 
132 /*!
133  * \brief Copies a file
134  * \param oldname name of the file you wish to copy (minus extension)
135  * \param newname name you wish the file to be copied to (minus extension)
136  * \param fmt the format of the file
137  * Copy a given file in a given format, or if fmt is NULL, then do so for all
138  */
139 int ast_filecopy(const char *oldname, const char *newname, const char *fmt);
140 
141 /*!
142  * \brief same as mkstemp, but return a FILE
143  * \param template_name The template for the unique file name to generate.
144  * Modified in place to return the file name.
145  * \param mode The mode for file permissions
146  *
147  * \return FILE handle to the temporary file on success or NULL if creation failed
148  */
149 FILE *ast_file_mkftemp(char *template_name, mode_t mode);
150 
151 /*!
152  * \brief Create a temporary file located at path
153  *
154  * \note The directory containing path will be created if it does not exist
155  * \note This function assumes path does not end with a '/'
156  *
157  * \param path The directory path to create the file in
158  * \param filename Function allocates memory and stores full filename (including path) here
159  * \param template_name mkstemp template to use. Must end with XXXXXX.
160  *
161  * \note filename will need to be freed with ast_free if this function succeeds
162  *
163  * \retval -1 on failure
164  * \return file descriptor on success
165  */
166 int ast_file_fdtemp(const char *path, char **filename, const char *template_name);
167 
168 /*!
169  * \brief Callback called for each file found when reading directories
170  * \param dir_name the name of the directory
171  * \param filename the name of the file
172  * \param obj user data object
173  * \retval non-zero to stop reading, otherwise zero to continue
174  *
175  * \note dir_name is not processed by realpath or other functions,
176  * symbolic links are not resolved. This ensures dir_name
177  * always starts with the exact string originally passed to
178  * \ref ast_file_read_dir or \ref ast_file_read_dirs.
179  */
180 typedef int (*ast_file_on_file)(const char *dir_name, const char *filename, void *obj);
181 
182 /*!
183  * \brief Recursively iterate through files and directories up to max_depth
184  * \param dir_name the name of the directory to search
185  * \param on_file callback called on each file
186  * \param obj user data object
187  * \param max_depth re-curse into sub-directories up to a given maximum (-1 = infinite)
188  * \retval -1 on failure
189  * \retval errno on failure
190  * \retval 0 otherwise
191  */
192 int ast_file_read_dirs(const char *dir_name, ast_file_on_file on_file, void *obj, int max_depth);
193 
194 /*!
195  * \brief Iterate over each file in a given directory
196  * \param dir_name the name of the directory to search
197  * \param on_file callback called on each file
198  * \param obj user data object
199  * \return -1
200  * \retval errno on failure
201  * \retval 0 otherwise
202  */
203 #define ast_file_read_dir(dir_name, on_file, obj) ast_file_read_dirs(dir_name, on_file, obj, 1)
204 
205 /*!
206  * \brief Waits for a stream to stop or digit to be pressed
207  * \param c channel to waitstream on
208  * \param breakon string of DTMF digits to break upon
209  * Begins playback of a stream...
210  * Wait for a stream to stop or for any one of a given digit to arrive,
211  * \retval 0 if the stream finishes
212  * \retval character if it was interrupted by the channel.
213  * \retval -1 on error
214  */
215 int ast_waitstream(struct ast_channel *c, const char *breakon);
216 
217 /*!
218  * \brief Waits for a stream to stop or digit matching a valid one digit exten to be pressed
219  * \param c channel to waitstream on
220  * \param context string of context to match digits to break upon
221  * Begins playback of a stream...
222  * Wait for a stream to stop or for any one of a valid extension digit to arrive,
223  * \retval 0 if the stream finishes.
224  * \retval character if it was interrupted.
225  * \retval -1 on error.
226  */
227 int ast_waitstream_exten(struct ast_channel *c, const char *context);
228 
229 /*!
230  * \brief Same as waitstream but allows stream to be forwarded or rewound
231  * \param c channel to waitstream on
232  * \param breakon string of DTMF digits to break upon
233  * \param forward DTMF digit to fast forward upon
234  * \param rewind DTMF digit to rewind upon
235  * \param ms How many miliseconds to skip forward/back
236  * Begins playback of a stream...
237  * Wait for a stream to stop or for any one of a given digit to arrive,
238  * \retval 0 if the stream finishes.
239  * \retval character if it was interrupted,
240  * \return the value of the control frame if it was interrupted by some other party,
241  * \retval -1 on error.
242  */
243 int ast_waitstream_fr(struct ast_channel *c, const char *breakon, const char *forward, const char *rewind, int ms);
244 
245 /*!
246  * \brief Same as waitstream_fr but allows a callback to be alerted when a user
247  * fastforwards or rewinds the file.
248  * \param c channel to waitstream on
249  * \param breakon string of DTMF digits to break upon
250  * \param forward DTMF digit to fast forward upon
251  * \param rewind DTMF digit to rewind upon
252  * \param ms How many milliseconds to skip forward/back
253  * \param cb to call when rewind or fastforward occurs.
254  * Begins playback of a stream...
255  * Wait for a stream to stop or for any one of a given digit to arrive,
256  * \retval 0 if the stream finishes.
257  * \retval character if it was interrupted,
258  * \return the value of the control frame if it was interrupted by some other party,
259  * \retval -1 on error.
260  */
261 int ast_waitstream_fr_w_cb(struct ast_channel *c,
262  const char *breakon,
263  const char *forward,
264  const char *rewind,
265  int ms,
267 
268 /*!
269  * Same as waitstream, but with audio output to fd and monitored fd checking.
270  *
271  * \retval 1 if monfd is ready for reading
272  */
273 int ast_waitstream_full(struct ast_channel *c, const char *breakon, int audiofd, int monfd);
274 
275 /*!
276  * \brief Starts reading from a file
277  * \param filename the name of the file to read from
278  * \param type format of file you wish to read from
279  * \param comment comment to go with
280  * \param flags file flags
281  * \param check (unimplemented, hence negligible)
282  * \param mode Open mode
283  * Open an incoming file stream. flags are flags for the open() command, and
284  * if check is non-zero, then it will not read a file if there are any files that
285  * start with that name and have an extension
286  * Please note, this is a blocking function. Program execution will not return until ast_waitstream completes it's execution.
287  * \return a struct ast_filestream on success.
288  * \retval NULL on failure.
289  */
290 struct ast_filestream *ast_readfile(const char *filename, const char *type, const char *comment, int flags, int check, mode_t mode);
291 
292 /*!
293  * \brief Starts writing a file
294  * \param filename the name of the file to write to
295  * \param type format of file you wish to write out to
296  * \param comment comment to go with
297  * \param flags output file flags
298  * \param check (unimplemented, hence negligible)
299  * \param mode Open mode
300  * Create an outgoing file stream. oflags are flags for the open() command, and
301  * if check is non-zero, then it will not write a file if there are any files that
302  * start with that name and have an extension
303  * Please note, this is a blocking function. Program execution will not return until ast_waitstream completes it's execution.
304  * \return a struct ast_filestream on success.
305  * \retval NULL on failure.
306  */
307 struct ast_filestream *ast_writefile(const char *filename, const char *type, const char *comment, int flags, int check, mode_t mode);
308 
309 /*!
310  * \brief Writes a frame to a stream
311  * \param fs filestream to write to
312  * \param f frame to write to the filestream
313  * Send a frame to a filestream -- note: does NOT free the frame, call ast_frfree manually
314  * \retval 0 on success.
315  * \retval -1 on failure.
316  */
317 int ast_writestream(struct ast_filestream *fs, struct ast_frame *f);
318 
319 /*!
320  * \brief Closes a stream
321  * \param f filestream to close
322  * Close a playback or recording stream
323  * \retval 0 on success.
324  * \retval -1 on failure.
325  */
326 int ast_closestream(struct ast_filestream *f);
327 
328 /*!
329  * \brief Opens stream for use in seeking, playing
330  * \param chan channel to work with
331  * \param filename to use
332  * \param preflang prefered language to use
333  * \return a ast_filestream pointer if it opens the file.
334  * \retval NULL on error.
335  */
336 struct ast_filestream *ast_openstream(struct ast_channel *chan, const char *filename, const char *preflang);
337 
338 /*!
339  * \brief Opens stream for use in seeking, playing
340  * \param chan channel to work with
341  * \param filename to use
342  * \param preflang prefered language to use
343  * \param asis if set, don't clear generators
344  * \retval a ast_filestream pointer if it opens the file.
345  * \retval NULL on error.
346  */
347 struct ast_filestream *ast_openstream_full(struct ast_channel *chan, const char *filename, const char *preflang, int asis);
348 /*!
349  * \brief Opens stream for use in seeking, playing
350  * \param chan channel to work with
351  * \param filename to use
352  * \param preflang prefered language to use
353  * \return a ast_filestream pointer if it opens the file.
354  * \retval NULL on error.
355  */
356 struct ast_filestream *ast_openvstream(struct ast_channel *chan, const char *filename, const char *preflang);
357 
358 /*!
359  * \brief Applies a open stream to a channel.
360  * \param chan channel to work
361  * \param s ast_filestream to apply
362  * \retval 0 on success.
363  * \retval -1 on failure.
364  */
365 int ast_applystream(struct ast_channel *chan, struct ast_filestream *s);
366 
367 /*!
368  * \brief Play a open stream on a channel.
369  * \param s filestream to play
370  * \retval 0 on success.
371  * \retval -1 on failure.
372  */
373 int ast_playstream(struct ast_filestream *s);
374 
375 /*!
376  * \brief Seeks into stream
377  * \param fs ast_filestream to perform seek on
378  * \param sample_offset numbers of samples to seek
379  * \param whence SEEK_SET, SEEK_CUR, SEEK_END
380  * \retval 0 on success.
381  * \retval -1 on failure.
382  */
383 int ast_seekstream(struct ast_filestream *fs, off_t sample_offset, int whence);
384 
385 /*!
386  * \brief Trunc stream at current location
387  * \param fs filestream to act on
388  * \retval 0 on success.
389  * \retval -1 on failure.
390  */
391 int ast_truncstream(struct ast_filestream *fs);
392 
393 /*!
394  * \brief Fast forward stream ms
395  * \param fs filestream to act on
396  * \param ms milliseconds to move
397  * \retval 0 on success.
398  * \retval -1 on failure.
399  */
400 int ast_stream_fastforward(struct ast_filestream *fs, off_t ms);
401 
402 /*!
403  * \brief Rewind stream ms
404  * \param fs filestream to act on
405  * \param ms milliseconds to move
406  * \retval 0 on success.
407  * \retval -1 on failure.
408  */
409 int ast_stream_rewind(struct ast_filestream *fs, off_t ms);
410 
411 /*!
412  * \brief Tell where we are in a stream
413  * \param fs fs to act on
414  * \return a long as a sample offset into stream
415  */
416 off_t ast_tellstream(struct ast_filestream *fs);
417 
418 /*!
419  * \brief Return the sample rate of the stream's format
420  * \param fs fs to act on
421  * \return sample rate in Hz
422  */
423 int ast_ratestream(struct ast_filestream *fs);
424 
425 /*!
426  * \brief Read a frame from a filestream
427  * \param s ast_filestream to act on
428  * \return a frame.
429  * \retval NULL if read failed.
430  */
431 struct ast_frame *ast_readframe(struct ast_filestream *s);
432 
433 /*! Initialize file stuff */
434 /*!
435  * Initializes all the various file stuff. Basically just registers the cli stuff
436  * Returns 0 all the time
437  */
438 int ast_file_init(void);
439 
440 
441 #define AST_RESERVED_POINTERS 20
442 
443 /*! Remove duplicate formats from a format string. */
444 /*!
445  * \param fmts a format string, this string will be modified
446  * \retval NULL error
447  * \return a pointer to the reduced format string, this is a pointer to fmts
448  */
449 char *ast_format_str_reduce(char *fmts);
450 
451 /*!
452  * \brief Get the ast_format associated with the given file extension
453  * \since 12
454  *
455  * \param file_ext The file extension for which to find the format
456  *
457  * \retval NULL if not found
458  * \return A pointer to the ast_format associated with this file extension
459  */
460 struct ast_format *ast_get_format_for_file_ext(const char *file_ext);
461 
462 /*!
463  * \brief Get a suitable filename extension for the given MIME type
464  *
465  * \param mime_type The MIME type for which to find extensions
466  * \param buffer A pointer to a buffer to receive the extension
467  * \param capacity The size of 'buffer' in bytes
468  *
469  * \retval 1 if an extension was found for the provided MIME type
470  * \retval 0 if the MIME type was not found
471  */
472 int ast_get_extension_for_mime_type(const char *mime_type, char *buffer, size_t capacity);
473 
474 #if defined(__cplusplus) || defined(c_plusplus)
475 }
476 #endif
477 
478 #endif /* _ASTERISK_FILE_H */
int ast_filecopy(const char *oldname, const char *newname, const char *fmt)
Copies a file.
Definition: file.c:1151
Main Channel structure associated with a channel.
void( ast_waitstream_fr_cb)(struct ast_channel *chan, long ms, enum ast_waitstream_fr_cb_values val)
callback used during dtmf controlled file playback to indicate location of playback in a file after r...
Definition: file.h:65
int ast_streamfile(struct ast_channel *c, const char *filename, const char *preflang)
Streams a file.
Definition: file.c:1293
char context[AST_MAX_CONTEXT]
Definition of a media format.
Definition: format.c:43
ast_waitstream_fr_cb_values
Definition: file.h:54
struct ast_filestream * ast_openstream_full(struct ast_channel *chan, const char *filename, const char *preflang, int asis)
Opens stream for use in seeking, playing.
Definition: file.c:795
int ast_filedelete(const char *filename, const char *fmt)
Deletes a file.
Definition: file.c:1141
int ast_file_read_dirs(const char *dir_name, ast_file_on_file on_file, void *obj, int max_depth)
Recursively iterate through files and directories up to max_depth.
Definition: file.c:1274
int ast_stream_fastforward(struct ast_filestream *fs, off_t ms)
Fast forward stream ms.
Definition: file.c:1095
off_t ast_tellstream(struct ast_filestream *fs)
Tell where we are in a stream.
Definition: file.c:1085
int ast_playstream(struct ast_filestream *s)
Play a open stream on a channel.
Definition: file.c:1063
struct ast_filestream * ast_openvstream(struct ast_channel *chan, const char *filename, const char *preflang)
Opens stream for use in seeking, playing.
Definition: file.c:848
char * ast_format_str_reduce(char *fmts)
Definition: file.c:1894
int ast_waitstream_fr(struct ast_channel *c, const char *breakon, const char *forward, const char *rewind, int ms)
Same as waitstream but allows stream to be forwarded or rewound.
Definition: file.c:1809
int ast_ratestream(struct ast_filestream *fs)
Return the sample rate of the stream's format.
Definition: file.c:1090
int(* ast_file_on_file)(const char *dir_name, const char *filename, void *obj)
Callback called for each file found when reading directories.
Definition: file.h:180
int ast_applystream(struct ast_channel *chan, struct ast_filestream *s)
Applies a open stream to a channel.
Definition: file.c:1057
struct ast_frame * ast_readframe(struct ast_filestream *s)
Read a frame from a filestream.
Definition: file.c:936
int ast_stream_rewind(struct ast_filestream *fs, off_t ms)
Rewind stream ms.
Definition: file.c:1100
struct ast_filestream * ast_writefile(const char *filename, const char *type, const char *comment, int flags, int check, mode_t mode)
Starts writing a file.
Definition: file.c:1423
int ast_seekstream(struct ast_filestream *fs, off_t sample_offset, int whence)
Seeks into stream.
Definition: file.c:1075
int ast_stream_and_wait(struct ast_channel *chan, const char *file, const char *digits)
stream file until digit If the file name is non-empty, try to play it.
Definition: file.c:1878
int ast_closestream(struct ast_filestream *f)
Closes a stream.
Definition: file.c:1111
struct ast_format * ast_get_format_for_file_ext(const char *file_ext)
Get the ast_format associated with the given file extension.
Definition: file.c:2006
int ast_truncstream(struct ast_filestream *fs)
Trunc stream at current location.
Definition: file.c:1080
int ast_file_fdtemp(const char *path, char **filename, const char *template_name)
Create a temporary file located at path.
Definition: file.c:202
int ast_waitstream_full(struct ast_channel *c, const char *breakon, int audiofd, int monfd)
Definition: file.c:1849
This structure is allocated by file.c in one chunk, together with buf_size and desc_size bytes of mem...
Definition: mod_format.h:101
FILE * ast_file_mkftemp(char *template_name, mode_t mode)
same as mkstemp, but return a FILE
Definition: file.c:187
int ast_writestream(struct ast_filestream *fs, struct ast_frame *f)
Writes a frame to a stream.
Definition: file.c:244
int ast_waitstream(struct ast_channel *c, const char *breakon)
Waits for a stream to stop or digit to be pressed.
Definition: file.c:1840
int ast_fileexists(const char *filename, const char *fmt, const char *preflang)
Checks for the existence of a given file.
Definition: file.c:1129
Data structure associated with a single frame of data.
struct ast_filestream * ast_readfile(const char *filename, const char *type, const char *comment, int flags, int check, mode_t mode)
Starts reading from a file.
Definition: file.c:1371
int ast_filerename(const char *oldname, const char *newname, const char *fmt)
Renames a file.
Definition: file.c:1146
int ast_get_extension_for_mime_type(const char *mime_type, char *buffer, size_t capacity)
Get a suitable filename extension for the given MIME type.
Definition: file.c:2019
int ast_stopstream(struct ast_channel *c)
Stops a stream.
Definition: file.c:222
int ast_file_init(void)
Definition: file.c:2051
struct ast_filestream * ast_openstream(struct ast_channel *chan, const char *filename, const char *preflang)
Opens stream for use in seeking, playing.
Definition: file.c:790
int ast_waitstream_fr_w_cb(struct ast_channel *c, const char *breakon, const char *forward, const char *rewind, int ms, ast_waitstream_fr_cb cb)
Same as waitstream_fr but allows a callback to be alerted when a user fastforwards or rewinds the fil...
Definition: file.c:1798
int ast_waitstream_exten(struct ast_channel *c, const char *context)
Waits for a stream to stop or digit matching a valid one digit exten to be pressed.
Definition: file.c:1859