libavformat/avio.c File Reference

#include <unistd.h>
#include "libavutil/avstring.h"
#include "libavutil/dict.h"
#include "libavutil/opt.h"
#include "os_support.h"
#include "avformat.h"
#include "url.h"

Go to the source code of this file.

Defines

#define URL_SCHEME_CHARS

Functions

URLProtocol * ffurl_protocol_next (URLProtocol *prev)

Iterate over all available protocols.

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

Iterate through names of available protocols.

int ffurl_register_protocol (URLProtocol *protocol, int size)

Register the URLProtocol protocol.

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.

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.

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.

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.

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.

int ffurl_write (URLContext *h, const unsigned char *buf, int size)

Write size bytes from buf to the resource accessed by h.

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.

int ffurl_close (URLContext *h)

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

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.

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.

int ffurl_get_file_handle (URLContext *h)

Return the file descriptor associated with this URL.

int ffurl_shutdown (URLContext *h, int flags)

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

int ff_check_interrupt (AVIOInterruptCB *cb)

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

Variables

static URLProtocol * first_protocol = NULL

Logging context.

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

const AVClass ffurl_context_class

static const char * urlcontext_to_name (void *ptr)

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

static const AVClass * urlcontext_child_class_next (const AVClass *prev)

Define Documentation

#define URL_SCHEME_CHARS

Value:

"abcdefghijklmnopqrstuvwxyz"                \
    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"                \
    "0123456789+-."

Definition at line 196 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 338 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.

Note:: it is recommended to use av_protocol_next() instead of this

Parameters:

	opaque	A 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.
	output	If 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 87 of file avio.c.

Referenced by avio_enum_protocols(), and opt_protocols().

int ff_check_interrupt ( AVIOInterruptCB * cb )

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

Definition at line 386 of file avio.c.

Referenced by avformat_find_stream_info(), do_tls_poll(), 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:

	puc	pointer to the location where, in case of success, the function puts the pointer to the created URLContext
	flags	flags which control how the resource indicated by url is to be opened
	int_cb	interrupt 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 201 of file avio.c.

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

int ffurl_close ( URLContext * h )

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

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

Definition at line 318 of file avio.c.

Referenced by avio_check(), avio_close(), avio_open2(), cache_close(), close_connection(), concat_close(), concat_open(), crypto_close(), ff_rtsp_undo_setup(), ffurl_open(), free_variant_list(), gopher_close(), hls_close(), hls_read(), hls_read_seek(), http_close(), http_open_cnx(), http_seek(), md5_close(), mms_close(), mmsh_close(), mmsh_open_internal(), mmsh_read_seek(), open_input(), read_data(), recheck_discard_flags(), rtmp_close(), rtp_close(), rtp_new_av_stream(), rtp_open(), sap_read_close(), sap_write_close(), tls_close(), and tls_open().

int ffurl_connect	(	URLContext *	uc,
		AVDictionary **	options
	)

Connect an URLContext that has been allocated by ffurl_alloc.

Parameters:

options

A 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 180 of file avio.c.

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

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 372 of file avio.c.

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

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:

	puc	pointer to the location where, in case of success, the function puts the pointer to the created URLContext
	flags	flags which control how the resource indicated by url is to be opened
	int_cb	interrupt callback to use for the URLContext, may be NULL
	options	A 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 235 of file avio.c.

Referenced by avio_open2(), cache_open(), concat_open(), crypto_open(), gopher_open(), hls_read(), http_open_cnx(), md5_close(), mms_open(), open_input(), rtmp_open(), rtp_new_av_stream(), rtp_open(), sap_read_header(), sap_write_header(), and tls_open().

URLProtocol* ffurl_protocol_next ( URLProtocol * prev )

Iterate over all available protocols.

Parameters:

prev

result of the previous call to this functions or NULL.

Definition at line 36 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 283 of file avio.c.

Referenced by cache_read(), concat_read(), crypto_read(), ff_rtmp_packet_read(), ffio_fdopen(), gopher_read(), hls_read(), http_buf_read(), http_getc(), read_data(), sap_fetch_packet(), and sap_read_header().

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 290 of file avio.c.

Referenced by ff_rtmp_packet_read(), ff_rtsp_tcp_read_packet(), get_chunk_header(), get_http_header_data(), get_tcp_server_response(), open_input(), read_data_packet(), and rtmp_handshake().

int ffurl_register_protocol	(	URLProtocol *	protocol,
		int	size
	)

Register the URLProtocol protocol.

Parameters:

size

the size of the URLProtocol struct referenced

Definition at line 97 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:

	pos	specifies the new position to set
	whence	specifies 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 308 of file avio.c.

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

int ffurl_shutdown	(	URLContext *	h,
		int	flags
	)

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

Parameters:

	h	pointer to the resource
	flags	flags 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 379 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 357 of file avio.c.

Referenced by concat_open().

int ffurl_write	(	URLContext *	h,
		const unsigned char *	buf,
		int	size
	)

Write size bytes from buf to the resource accessed by h.

Returns:: the number of bytes actually written, or a negative value corresponding to an AVERROR code in case of failure

Definition at line 297 of file avio.c.

Referenced by ff_rtmp_packet_write(), ff_rtp_check_and_send_back_rr(), ff_rtp_send_punch_packets(), ffio_fdopen(), gopher_write(), http_connect(), http_send_data(), http_shutdown(), http_write(), md5_close(), rtmp_handshake(), rtp_write(), sap_write_close(), sap_write_packet(), send_command_packet(), and tcp_write_packet().

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
	)			`[inline, static]`

Definition at line 253 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 112 of file avio.c.

Referenced by ffurl_alloc().

static const AVClass* urlcontext_child_class_next ( const AVClass * prev ) [static]

Definition at line 58 of file avio.c.

static void* urlcontext_child_next	(	void *	obj,
		void *	prev
	)			`[static]`

Definition at line 50 of file avio.c.

static const char* urlcontext_to_name ( void * ptr ) [static]

Definition at line 43 of file avio.c.

Variable Documentation

const AVClass ffurl_context_class

Initial value:

 {
    .class_name     = "URLContext",
    .item_name      = urlcontext_to_name,
    .option         = options,
    .version        = LIBAVUTIL_VERSION_INT,
    .child_next     = urlcontext_child_next,
    .child_class_next = urlcontext_child_class_next,
}

Definition at line 76 of file avio.c.

Referenced by ffio_url_child_class_next().

URLProtocol* first_protocol = NULL [static]

Definition at line 34 of file avio.c.

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

Definition at line 75 of file avio.c.


Defines
#define	URL_SCHEME_CHARS
Functions
URLProtocol *	ffurl_protocol_next (URLProtocol *prev)
	Iterate over all available protocols.
const char *	avio_enum_protocols (void **opaque, int output)
	Iterate through names of available protocols.
int	ffurl_register_protocol (URLProtocol *protocol, int size)
	Register the URLProtocol protocol.
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.
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.
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.
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.
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.
int	ffurl_write (URLContext h, const unsigned char buf, int size)
	Write size bytes from buf to the resource accessed by h.
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.
int	ffurl_close (URLContext *h)
	Close the resource accessed by the URLContext h, and free the memory used by it.
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.
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.
int	ffurl_get_file_handle (URLContext *h)
	Return the file descriptor associated with this URL.
int	ffurl_shutdown (URLContext *h, int flags)
	Signal the URLContext that we are done reading or writing the stream.
int	ff_check_interrupt (AVIOInterruptCB *cb)
	Check if the user has requested to interrup a blocking function associated with cb.
Variables
static URLProtocol *	first_protocol = NULL
Logging context.
static const AVOption	options [] = {{NULL}}
const AVClass	ffurl_context_class
static const char *	urlcontext_to_name (void *ptr)
static void *	urlcontext_child_next (void obj, void prev)
static const AVClass *	urlcontext_child_class_next (const AVClass *prev)