avio.c File Reference
#include "libavutil/avstring.h"
#include "libavutil/dict.h"
#include "libavutil/opt.h"
#include "libavutil/time.h"
#include "os_support.h"
#include "avformat.h"
#include "url.h"
Include dependency graph for avio.c:

Go to the source code of this file.

Macros

#define URL_SCHEME_CHARS
 

Functions

URLProtocolffurl_protocol_next (URLProtocol *prev)
 Iterate over all available protocols. More...
 
const char * avio_enum_protocols (void **opaque, int output)
 Iterate through names of available protocols. More...
 
int ffurl_register_protocol (URLProtocol *protocol, int size)
 Register the URLProtocol protocol. More...
 
static int url_alloc_for_protocol (URLContext **puc, struct URLProtocol *up, const char *filename, int flags, const AVIOInterruptCB *int_cb)
 
int ffurl_connect (URLContext *uc, AVDictionary **options)
 Connect an URLContext that has been allocated by ffurl_alloc. More...
 
int ffurl_alloc (URLContext **puc, const char *filename, int flags, const AVIOInterruptCB *int_cb)
 Create a URLContext for accessing to the resource indicated by url, but do not initiate the connection yet. More...
 
int ffurl_open (URLContext **puc, const char *filename, int flags, const AVIOInterruptCB *int_cb, AVDictionary **options)
 Create an URLContext for accessing to the resource indicated by url, and open it. More...
 
static int retry_transfer_wrapper (URLContext *h, unsigned char *buf, int size, int size_min, int(*transfer_func)(URLContext *h, unsigned char *buf, int size))
 
int ffurl_read (URLContext *h, unsigned char *buf, int size)
 Read up to size bytes from the resource accessed by h, and store the read bytes in buf. More...
 
int ffurl_read_complete (URLContext *h, unsigned char *buf, int size)
 Read as many bytes as possible (up to size), calling the read function multiple times if necessary. More...
 
int ffurl_write (URLContext *h, const unsigned char *buf, int size)
 Write size bytes from buf to the resource accessed by h. More...
 
int64_t ffurl_seek (URLContext *h, int64_t pos, int whence)
 Change the position that will be used by the next read/write operation on the resource accessed by h. More...
 
int ffurl_closep (URLContext **hh)
 Close the resource accessed by the URLContext h, and free the memory used by it. More...
 
int ffurl_close (URLContext *h)
 
int avio_check (const char *url, int flags)
 Return AVIO_FLAG_* access flags corresponding to the access permissions of the resource in url, or a negative value corresponding to an AVERROR code in case of failure. More...
 
int64_t ffurl_size (URLContext *h)
 Return the filesize of the resource accessed by h, AVERROR(ENOSYS) if the operation is not supported by h, or another negative value corresponding to an AVERROR error code in case of failure. More...
 
int ffurl_get_file_handle (URLContext *h)
 Return the file descriptor associated with this URL. More...
 
int ffurl_get_multi_file_handle (URLContext *h, int **handles, int *numhandles)
 Return the file descriptors associated with this URL. More...
 
int ffurl_shutdown (URLContext *h, int flags)
 Signal the URLContext that we are done reading or writing the stream. More...
 
int ff_check_interrupt (AVIOInterruptCB *cb)
 Check if the user has requested to interrup a blocking function associated with cb. More...
 

Variables

static URLProtocolfirst_protocol = NULL
 

Logging context.

static const AVOption options [] = {{NULL}}
 
const AVClass ffurl_context_class
 
static const char * urlcontext_to_name (void *ptr)
 
static voidurlcontext_child_next (void *obj, void *prev)
 
static const AVClassurlcontext_child_class_next (const AVClass *prev)
 

Macro Definition Documentation

#define URL_SCHEME_CHARS
Value:
"abcdefghijklmnopqrstuvwxyz" \
"ABCDEFGHIJKLMNOPQRSTUVWXYZ" \
"0123456789+-."

Definition at line 206 of file avio.c.

Referenced by ffurl_alloc().

Function Documentation

int avio_check ( const char *  url,
int  flags 
)

Return AVIO_FLAG_* access flags corresponding to the access permissions of the resource in url, or a negative value corresponding to an AVERROR code in case of failure.

The returned access flags are masked by the value in flags.

Note
This function is intrinsically unsafe, in the sense that the checked resource may change its existence or permission status from one call to another. Thus you should not trust the returned value, unless you are sure that no other processes are accessing the checked resource.

Definition at line 365 of file avio.c.

Referenced by assert_file_overwrite(), build_feed_streams(), and find_image_range().

const char* avio_enum_protocols ( void **  opaque,
int  output 
)

Iterate through names of available protocols.

Parameters
opaqueA private pointer representing current protocol. It must be a pointer to NULL on first iteration and will be updated by successive calls to avio_enum_protocols.
outputIf set to 1, iterate over output protocols, otherwise over input protocols.
Returns
A static string containing the name of current protocol or NULL

Definition at line 86 of file avio.c.

Referenced by avio_enum_protocols(), and show_protocols().

int ff_check_interrupt ( AVIOInterruptCB cb)

Check if the user has requested to interrup a blocking function associated with cb.

Definition at line 428 of file avio.c.

Referenced by avformat_find_stream_info(), do_tls_poll(), ff_network_wait_fd_timeout(), ff_rtsp_open_transport_ctx(), hls_read(), read_data(), retry_transfer_wrapper(), rtp_read(), and tcp_open().

int ffurl_alloc ( URLContext **  puc,
const char *  filename,
int  flags,
const AVIOInterruptCB int_cb 
)

Create a URLContext for accessing to the resource indicated by url, but do not initiate the connection yet.

Parameters
pucpointer to the location where, in case of success, the function puts the pointer to the created URLContext
flagsflags which control how the resource indicated by url is to be opened
int_cbinterrupt callback to use for the URLContext, may be NULL
Returns
0 in case of success, a negative value corresponding to an AVERROR code in case of failure

Definition at line 211 of file avio.c.

Referenced by avio_check(), ff_rtsp_open_transport_ctx(), ffurl_open(), mmsh_open_internal(), open_input(), and rtmp_http_open().

int ffurl_closep ( URLContext **  h)

Close the resource accessed by the URLContext h, and free the memory used by it.

Also set the URLContext pointer to NULL.

Returns
a negative value if an error condition occurred, 0 otherwise

Definition at line 338 of file avio.c.

Referenced by ffurl_close(), http_close(), http_get_file_handle(), and http_open_cnx().

int ffurl_connect ( URLContext uc,
AVDictionary **  options 
)

Connect an URLContext that has been allocated by ffurl_alloc.

Parameters
optionsA dictionary filled with options for nested protocols, i.e. it will be passed to url_open2() for protocols implementing it. This parameter will be destroyed and replaced with a dict containing options that were not found. May be NULL.

Definition at line 190 of file avio.c.

Referenced by avio_check(), ff_rtsp_open_transport_ctx(), ffurl_open(), mmsh_open_internal(), open_input(), and rtmp_http_open().

int ffurl_get_file_handle ( URLContext h)

Return the file descriptor associated with this URL.

For RTP, this will return only the RTP file descriptor, not the RTCP file descriptor.

Returns
the file descriptor associated with this URL, or <0 on error.

Definition at line 399 of file avio.c.

Referenced by ff_rtsp_open_transport_ctx(), http_get_file_handle(), rtp_open(), rtsp_write_packet(), sap_fetch_packet(), sap_write_header(), srtp_get_file_handle(), and tls_open().

int ffurl_get_multi_file_handle ( URLContext h,
int **  handles,
int *  numhandles 
)

Return the file descriptors associated with this URL.

Returns
0 on success or <0 on error.

Definition at line 406 of file avio.c.

Referenced by ff_rtsp_open_transport_ctx(), and srtp_get_multi_file_handle().

int ffurl_open ( URLContext **  puc,
const char *  filename,
int  flags,
const AVIOInterruptCB int_cb,
AVDictionary **  options 
)

Create an URLContext for accessing to the resource indicated by url, and open it.

Parameters
pucpointer to the location where, in case of success, the function puts the pointer to the created URLContext
flagsflags which control how the resource indicated by url is to be opened
int_cbinterrupt callback to use for the URLContext, may be NULL
optionsA dictionary filled with protocol-private options. On return this parameter will be destroyed and replaced with a dict containing options that were not found. May be NULL.
Returns
0 in case of success, a negative value corresponding to an AVERROR code in case of failure

Definition at line 247 of file avio.c.

Referenced by avio_open2(), cache_open(), concat_open(), crypto_open2(), ff_rtsp_open_transport_ctx(), gopher_open(), hls_read(), http_get_file_handle(), http_open_cnx(), ism_flush(), ism_seek(), md5_close(), mms_open(), open_input(), rtmp_calc_swfhash(), rtmp_open(), rtmpe_open(), rtp_new_av_stream(), rtp_open(), rtsp_listen(), rtsp_read_setup(), sap_read_header(), sap_write_header(), srtp_open(), and tls_open().

URLProtocol* ffurl_protocol_next ( URLProtocol prev)

Iterate over all available protocols.

Parameters
prevresult of the previous call to this functions or NULL.

Definition at line 35 of file avio.c.

Referenced by avio_enum_protocols(), ffurl_alloc(), and urlcontext_child_class_next().

int ffurl_read ( URLContext h,
unsigned char *  buf,
int  size 
)

Read up to size bytes from the resource accessed by h, and store the read bytes in buf.

Returns
The number of bytes actually read, or a negative value corresponding to an AVERROR code in case of error. A value of zero indicates that it is not possible to read more from the accessed resource (except if the value of the size argument is also zero).

Definition at line 303 of file avio.c.

Referenced by cache_read(), concat_read(), crypto_read(), ff_rtmp_packet_read(), ff_rtsp_open_transport_ctx(), ffio_fdopen(), gopher_read(), hls_read(), http_buf_read(), http_getc(), read_data(), rtmp_http_open(), rtmp_http_read(), rtmp_http_send_cmd(), rtmp_write(), rtmpe_read(), sap_fetch_packet(), sap_read_header(), and srtp_read().

int ffurl_read_complete ( URLContext h,
unsigned char *  buf,
int  size 
)

Read as many bytes as possible (up to size), calling the read function multiple times if necessary.

This makes special short-read handling in applications unnecessary, if the return value is < size then it is certain there was either an error or the end of file was reached.

Definition at line 310 of file avio.c.

Referenced by ff_rtmp_packet_read_internal(), ff_rtsp_open_transport_ctx(), ff_rtsp_tcp_read_packet(), get_chunk_header(), get_http_header_data(), get_tcp_server_response(), open_input(), read_data_packet(), read_line(), rtmp_calc_swfhash(), rtmp_handshake(), rtmp_receive_hs_packet(), rtmp_server_handshake(), and rtsp_read_announce().

int ffurl_register_protocol ( URLProtocol protocol,
int  size 
)

Register the URLProtocol protocol.

Parameters
sizethe size of the URLProtocol struct referenced

Definition at line 96 of file avio.c.

int64_t ffurl_seek ( URLContext h,
int64_t  pos,
int  whence 
)

Change the position that will be used by the next read/write operation on the resource accessed by h.

Parameters
posspecifies the new position to set
whencespecifies how pos should be interpreted, it must be one of SEEK_SET (seek from the beginning), SEEK_CUR (seek from the current position), SEEK_END (seek from the end), or AVSEEK_SIZE (return the filesize of the requested resource, pos is ignored).
Returns
a negative value corresponding to an AVERROR code in case of failure, or the resulting file position, measured in bytes from the beginning of the file. You can use this feature together with SEEK_CUR to read the current file position.

Definition at line 328 of file avio.c.

Referenced by cache_seek(), concat_read(), concat_seek(), ffio_fdopen(), ffurl_connect(), ffurl_size(), ism_seek(), and rtmp_calc_swfhash().

int ffurl_shutdown ( URLContext h,
int  flags 
)

Signal the URLContext that we are done reading or writing the stream.

Parameters
hpointer to the resource
flagsflags which control how the resource indicated by url is to be shutdown
Returns
a negative value if an error condition occurred, 0 otherwise

Definition at line 421 of file avio.c.

int64_t ffurl_size ( URLContext h)

Return the filesize of the resource accessed by h, AVERROR(ENOSYS) if the operation is not supported by h, or another negative value corresponding to an AVERROR error code in case of failure.

Definition at line 384 of file avio.c.

Referenced by concat_open().

int ffurl_write ( URLContext h,
const unsigned char *  buf,
int  size 
)
static int retry_transfer_wrapper ( URLContext h,
unsigned char *  buf,
int  size,
int  size_min,
int(*)(URLContext *h, unsigned char *buf, int size transfer_func 
)
inlinestatic

Definition at line 265 of file avio.c.

Referenced by ffurl_read(), ffurl_read_complete(), and ffurl_write().

static int url_alloc_for_protocol ( URLContext **  puc,
struct URLProtocol up,
const char *  filename,
int  flags,
const AVIOInterruptCB int_cb 
)
static

Definition at line 111 of file avio.c.

Referenced by ffurl_alloc().

static const AVClass* urlcontext_child_class_next ( const AVClass prev)
static

Definition at line 57 of file avio.c.

static void* urlcontext_child_next ( void obj,
void prev 
)
static

Definition at line 49 of file avio.c.

static const char* urlcontext_to_name ( void ptr)
static

Definition at line 42 of file avio.c.

Variable Documentation

const AVClass ffurl_context_class
Initial value:
= {
.class_name = "URLContext",
.item_name = urlcontext_to_name,
.option = options,
.child_next = urlcontext_child_next,
.child_class_next = urlcontext_child_class_next,
}
static void * urlcontext_child_next(void *obj, void *prev)
Definition: avio.c:49
static const char * urlcontext_to_name(void *ptr)
Definition: avio.c:42
static const AVOption options[]
Definition: avio.c:74
static const AVClass * urlcontext_child_class_next(const AVClass *prev)
Definition: avio.c:57
LIBAVUTIL_VERSION_INT
Definition: eval.c:55

Definition at line 75 of file avio.c.

Referenced by ffio_url_child_class_next(), and url_alloc_for_protocol().

URLProtocol* first_protocol = NULL
static

Definition at line 33 of file avio.c.

Referenced by ffurl_protocol_next(), and ffurl_register_protocol().

const AVOption options[] = {{NULL}}
static

Definition at line 74 of file avio.c.