gstreamer/plugins/elements/gstfilesrc.c
Thibault Saunier a87b4551a6 Port gtk-doc comments to their equivalent markdown syntax
Modernizing our documentation and preparing a possible move to hotdoc.
This commits also adds missing @title metadatas to all SECTIONs
2017-01-27 16:36:38 -03:00

678 lines
17 KiB
C

/* GStreamer
* Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
* 2000,2005 Wim Taymans <wim@fluendo.com>
*
* gstfilesrc.c:
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
/**
* SECTION:element-filesrc
* @title: filesrc
* @see_also: #GstFileSrc
*
* Read data from a file in the local file system.
*
* ## Example launch line
* |[
* gst-launch-1.0 filesrc location=song.ogg ! decodebin ! audioconvert ! audioresample ! autoaudiosink
* ]| Play song.ogg audio file which must be in the current working directory.
*
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <gst/gst.h>
#include "gstfilesrc.h"
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#ifdef G_OS_WIN32
#include <io.h> /* lseek, open, close, read */
/* On win32, stat* default to 32 bit; we need the 64-bit
* variants, so explicitly define it that way. */
#undef stat
#define stat __stat64
#undef fstat
#define fstat _fstat64
#undef lseek
#define lseek _lseeki64
#undef off_t
#define off_t guint64
/* Prevent stat.h from defining the stat* functions as
* _stat*, since we're explicitly overriding that */
#undef _INC_STAT_INL
#endif
#include <fcntl.h>
#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif
#ifdef __BIONIC__ /* Android */
#undef lseek
#define lseek lseek64
#undef fstat
#define fstat fstat64
#undef off_t
#define off_t guint64
#endif
#include <errno.h>
#include <string.h>
#include "../../gst/gst-i18n-lib.h"
static GstStaticPadTemplate srctemplate = GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS_ANY);
#ifndef S_ISREG
#define S_ISREG(mode) ((mode)&_S_IFREG)
#endif
#ifndef S_ISDIR
#define S_ISDIR(mode) ((mode)&_S_IFDIR)
#endif
#ifndef S_ISSOCK
#define S_ISSOCK(x) (0)
#endif
#ifndef O_BINARY
#define O_BINARY (0)
#endif
/* Copy of glib's g_open due to win32 libc/cross-DLL brokenness: we can't
* use the 'file descriptor' opened in glib (and returned from this function)
* in this library, as they may have unrelated C runtimes. */
static int
gst_open (const gchar * filename, int flags, int mode)
{
#ifdef G_OS_WIN32
wchar_t *wfilename = g_utf8_to_utf16 (filename, -1, NULL, NULL, NULL);
int retval;
int save_errno;
if (wfilename == NULL) {
errno = EINVAL;
return -1;
}
retval = _wopen (wfilename, flags, mode);
save_errno = errno;
g_free (wfilename);
errno = save_errno;
return retval;
#elif defined (__BIONIC__)
return open (filename, flags | O_LARGEFILE, mode);
#else
return open (filename, flags, mode);
#endif
}
GST_DEBUG_CATEGORY_STATIC (gst_file_src_debug);
#define GST_CAT_DEFAULT gst_file_src_debug
/* FileSrc signals and args */
enum
{
/* FILL ME */
LAST_SIGNAL
};
#define DEFAULT_BLOCKSIZE 4*1024
enum
{
PROP_0,
PROP_LOCATION
};
static void gst_file_src_finalize (GObject * object);
static void gst_file_src_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
static void gst_file_src_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static gboolean gst_file_src_start (GstBaseSrc * basesrc);
static gboolean gst_file_src_stop (GstBaseSrc * basesrc);
static gboolean gst_file_src_is_seekable (GstBaseSrc * src);
static gboolean gst_file_src_get_size (GstBaseSrc * src, guint64 * size);
static GstFlowReturn gst_file_src_fill (GstBaseSrc * src, guint64 offset,
guint length, GstBuffer * buf);
static void gst_file_src_uri_handler_init (gpointer g_iface,
gpointer iface_data);
#define _do_init \
G_IMPLEMENT_INTERFACE (GST_TYPE_URI_HANDLER, gst_file_src_uri_handler_init); \
GST_DEBUG_CATEGORY_INIT (gst_file_src_debug, "filesrc", 0, "filesrc element");
#define gst_file_src_parent_class parent_class
G_DEFINE_TYPE_WITH_CODE (GstFileSrc, gst_file_src, GST_TYPE_BASE_SRC, _do_init);
static void
gst_file_src_class_init (GstFileSrcClass * klass)
{
GObjectClass *gobject_class;
GstElementClass *gstelement_class;
GstBaseSrcClass *gstbasesrc_class;
gobject_class = G_OBJECT_CLASS (klass);
gstelement_class = GST_ELEMENT_CLASS (klass);
gstbasesrc_class = GST_BASE_SRC_CLASS (klass);
gobject_class->set_property = gst_file_src_set_property;
gobject_class->get_property = gst_file_src_get_property;
g_object_class_install_property (gobject_class, PROP_LOCATION,
g_param_spec_string ("location", "File Location",
"Location of the file to read", NULL,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
GST_PARAM_MUTABLE_READY));
gobject_class->finalize = gst_file_src_finalize;
gst_element_class_set_static_metadata (gstelement_class,
"File Source",
"Source/File",
"Read from arbitrary point in a file",
"Erik Walthinsen <omega@cse.ogi.edu>");
gst_element_class_add_static_pad_template (gstelement_class, &srctemplate);
gstbasesrc_class->start = GST_DEBUG_FUNCPTR (gst_file_src_start);
gstbasesrc_class->stop = GST_DEBUG_FUNCPTR (gst_file_src_stop);
gstbasesrc_class->is_seekable = GST_DEBUG_FUNCPTR (gst_file_src_is_seekable);
gstbasesrc_class->get_size = GST_DEBUG_FUNCPTR (gst_file_src_get_size);
gstbasesrc_class->fill = GST_DEBUG_FUNCPTR (gst_file_src_fill);
if (sizeof (off_t) < 8) {
GST_LOG ("No large file support, sizeof (off_t) = %" G_GSIZE_FORMAT "!",
sizeof (off_t));
}
}
static void
gst_file_src_init (GstFileSrc * src)
{
src->filename = NULL;
src->fd = 0;
src->uri = NULL;
src->is_regular = FALSE;
gst_base_src_set_blocksize (GST_BASE_SRC (src), DEFAULT_BLOCKSIZE);
}
static void
gst_file_src_finalize (GObject * object)
{
GstFileSrc *src;
src = GST_FILE_SRC (object);
g_free (src->filename);
g_free (src->uri);
G_OBJECT_CLASS (parent_class)->finalize (object);
}
static gboolean
gst_file_src_set_location (GstFileSrc * src, const gchar * location,
GError ** err)
{
GstState state;
/* the element must be stopped in order to do this */
GST_OBJECT_LOCK (src);
state = GST_STATE (src);
if (state != GST_STATE_READY && state != GST_STATE_NULL)
goto wrong_state;
GST_OBJECT_UNLOCK (src);
g_free (src->filename);
g_free (src->uri);
/* clear the filename if we get a NULL */
if (location == NULL) {
src->filename = NULL;
src->uri = NULL;
} else {
/* we store the filename as received by the application. On Windows this
* should be UTF8 */
src->filename = g_strdup (location);
src->uri = gst_filename_to_uri (location, NULL);
GST_INFO ("filename : %s", src->filename);
GST_INFO ("uri : %s", src->uri);
}
g_object_notify (G_OBJECT (src), "location");
/* FIXME 2.0: notify "uri" property once there is one */
return TRUE;
/* ERROR */
wrong_state:
{
g_warning ("Changing the `location' property on filesrc when a file is "
"open is not supported.");
if (err)
g_set_error (err, GST_URI_ERROR, GST_URI_ERROR_BAD_STATE,
"Changing the `location' property on filesrc when a file is "
"open is not supported.");
GST_OBJECT_UNLOCK (src);
return FALSE;
}
}
static void
gst_file_src_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstFileSrc *src;
g_return_if_fail (GST_IS_FILE_SRC (object));
src = GST_FILE_SRC (object);
switch (prop_id) {
case PROP_LOCATION:
gst_file_src_set_location (src, g_value_get_string (value), NULL);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_file_src_get_property (GObject * object, guint prop_id, GValue * value,
GParamSpec * pspec)
{
GstFileSrc *src;
g_return_if_fail (GST_IS_FILE_SRC (object));
src = GST_FILE_SRC (object);
switch (prop_id) {
case PROP_LOCATION:
g_value_set_string (value, src->filename);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
/***
* read code below
* that is to say, you shouldn't read the code below, but the code that reads
* stuff is below. Well, you shouldn't not read the code below, feel free
* to read it of course. It's just that "read code below" is a pretty crappy
* documentation string because it sounds like we're expecting you to read
* the code to understand what it does, which, while true, is really not
* the sort of attitude we want to be advertising. No sir.
*
*/
static GstFlowReturn
gst_file_src_fill (GstBaseSrc * basesrc, guint64 offset, guint length,
GstBuffer * buf)
{
GstFileSrc *src;
guint to_read, bytes_read;
int ret;
GstMapInfo info;
guint8 *data;
src = GST_FILE_SRC_CAST (basesrc);
if (G_UNLIKELY (offset != -1 && src->read_position != offset)) {
off_t res;
res = lseek (src->fd, offset, SEEK_SET);
if (G_UNLIKELY (res < 0 || res != offset))
goto seek_failed;
src->read_position = offset;
}
if (!gst_buffer_map (buf, &info, GST_MAP_WRITE))
goto buffer_write_fail;
data = info.data;
bytes_read = 0;
to_read = length;
while (to_read > 0) {
GST_LOG_OBJECT (src, "Reading %d bytes at offset 0x%" G_GINT64_MODIFIER "x",
to_read, offset + bytes_read);
errno = 0;
ret = read (src->fd, data + bytes_read, to_read);
if (G_UNLIKELY (ret < 0)) {
if (errno == EAGAIN || errno == EINTR)
continue;
goto could_not_read;
}
/* files should eos if they read 0 and more was requested */
if (G_UNLIKELY (ret == 0)) {
/* .. but first we should return any remaining data */
if (bytes_read > 0)
break;
goto eos;
}
to_read -= ret;
bytes_read += ret;
src->read_position += ret;
}
gst_buffer_unmap (buf, &info);
if (bytes_read != length)
gst_buffer_resize (buf, 0, bytes_read);
GST_BUFFER_OFFSET (buf) = offset;
GST_BUFFER_OFFSET_END (buf) = offset + bytes_read;
return GST_FLOW_OK;
/* ERROR */
seek_failed:
{
GST_ELEMENT_ERROR (src, RESOURCE, READ, (NULL), GST_ERROR_SYSTEM);
return GST_FLOW_ERROR;
}
could_not_read:
{
GST_ELEMENT_ERROR (src, RESOURCE, READ, (NULL), GST_ERROR_SYSTEM);
gst_buffer_unmap (buf, &info);
gst_buffer_resize (buf, 0, 0);
return GST_FLOW_ERROR;
}
eos:
{
GST_DEBUG ("EOS");
gst_buffer_unmap (buf, &info);
gst_buffer_resize (buf, 0, 0);
return GST_FLOW_EOS;
}
buffer_write_fail:
{
GST_ELEMENT_ERROR (src, RESOURCE, WRITE, (NULL), ("Can't write to buffer"));
return GST_FLOW_ERROR;
}
}
static gboolean
gst_file_src_is_seekable (GstBaseSrc * basesrc)
{
GstFileSrc *src = GST_FILE_SRC (basesrc);
return src->seekable;
}
static gboolean
gst_file_src_get_size (GstBaseSrc * basesrc, guint64 * size)
{
struct stat stat_results;
GstFileSrc *src;
src = GST_FILE_SRC (basesrc);
if (!src->seekable) {
/* If it isn't seekable, we won't know the length (but fstat will still
* succeed, and wrongly say our length is zero. */
return FALSE;
}
if (fstat (src->fd, &stat_results) < 0)
goto could_not_stat;
*size = stat_results.st_size;
return TRUE;
/* ERROR */
could_not_stat:
{
return FALSE;
}
}
/* open the file, necessary to go to READY state */
static gboolean
gst_file_src_start (GstBaseSrc * basesrc)
{
GstFileSrc *src = GST_FILE_SRC (basesrc);
struct stat stat_results;
if (src->filename == NULL || src->filename[0] == '\0')
goto no_filename;
GST_INFO_OBJECT (src, "opening file %s", src->filename);
/* open the file */
src->fd = gst_open (src->filename, O_RDONLY | O_BINARY, 0);
if (src->fd < 0)
goto open_failed;
/* check if it is a regular file, otherwise bail out */
if (fstat (src->fd, &stat_results) < 0)
goto no_stat;
if (S_ISDIR (stat_results.st_mode))
goto was_directory;
if (S_ISSOCK (stat_results.st_mode))
goto was_socket;
src->read_position = 0;
/* record if it's a regular (hence seekable and lengthable) file */
if (S_ISREG (stat_results.st_mode))
src->is_regular = TRUE;
/* We need to check if the underlying file is seekable. */
{
off_t res = lseek (src->fd, 0, SEEK_END);
if (res < 0) {
GST_LOG_OBJECT (src, "disabling seeking, lseek failed: %s",
g_strerror (errno));
src->seekable = FALSE;
} else {
res = lseek (src->fd, 0, SEEK_SET);
if (res < 0) {
/* We really don't like not being able to go back to 0 */
src->seekable = FALSE;
goto lseek_wonky;
}
src->seekable = TRUE;
}
}
/* We can only really do seeking on regular files - for other file types, we
* don't know their length, so seeking isn't useful/meaningful */
src->seekable = src->seekable && src->is_regular;
gst_base_src_set_dynamic_size (basesrc, src->seekable);
return TRUE;
/* ERROR */
no_filename:
{
GST_ELEMENT_ERROR (src, RESOURCE, NOT_FOUND,
(_("No file name specified for reading.")), (NULL));
goto error_exit;
}
open_failed:
{
switch (errno) {
case ENOENT:
GST_ELEMENT_ERROR (src, RESOURCE, NOT_FOUND, (NULL),
("No such file \"%s\"", src->filename));
break;
default:
GST_ELEMENT_ERROR (src, RESOURCE, OPEN_READ,
(_("Could not open file \"%s\" for reading."), src->filename),
GST_ERROR_SYSTEM);
break;
}
goto error_exit;
}
no_stat:
{
GST_ELEMENT_ERROR (src, RESOURCE, OPEN_READ,
(_("Could not get info on \"%s\"."), src->filename), (NULL));
goto error_close;
}
was_directory:
{
GST_ELEMENT_ERROR (src, RESOURCE, OPEN_READ,
(_("\"%s\" is a directory."), src->filename), (NULL));
goto error_close;
}
was_socket:
{
GST_ELEMENT_ERROR (src, RESOURCE, OPEN_READ,
(_("File \"%s\" is a socket."), src->filename), (NULL));
goto error_close;
}
lseek_wonky:
{
GST_ELEMENT_ERROR (src, RESOURCE, OPEN_READ, (NULL),
("Could not seek back to zero after seek test in file \"%s\"",
src->filename));
goto error_close;
}
error_close:
close (src->fd);
error_exit:
return FALSE;
}
/* unmap and close the file */
static gboolean
gst_file_src_stop (GstBaseSrc * basesrc)
{
GstFileSrc *src = GST_FILE_SRC (basesrc);
/* close the file */
close (src->fd);
/* zero out a lot of our state */
src->fd = 0;
src->is_regular = FALSE;
return TRUE;
}
/*** GSTURIHANDLER INTERFACE *************************************************/
static GstURIType
gst_file_src_uri_get_type (GType type)
{
return GST_URI_SRC;
}
static const gchar *const *
gst_file_src_uri_get_protocols (GType type)
{
static const gchar *protocols[] = { "file", NULL };
return protocols;
}
static gchar *
gst_file_src_uri_get_uri (GstURIHandler * handler)
{
GstFileSrc *src = GST_FILE_SRC (handler);
/* FIXME: make thread-safe */
return g_strdup (src->uri);
}
static gboolean
gst_file_src_uri_set_uri (GstURIHandler * handler, const gchar * uri,
GError ** err)
{
gchar *location, *hostname = NULL;
gboolean ret = FALSE;
GstFileSrc *src = GST_FILE_SRC (handler);
if (strcmp (uri, "file://") == 0) {
/* Special case for "file://" as this is used by some applications
* to test with gst_element_make_from_uri if there's an element
* that supports the URI protocol. */
gst_file_src_set_location (src, NULL, NULL);
return TRUE;
}
location = g_filename_from_uri (uri, &hostname, err);
if (!location || (err != NULL && *err != NULL)) {
GST_WARNING_OBJECT (src, "Invalid URI '%s' for filesrc: %s", uri,
(err != NULL && *err != NULL) ? (*err)->message : "unknown error");
goto beach;
}
if ((hostname) && (strcmp (hostname, "localhost"))) {
/* Only 'localhost' is permitted */
GST_WARNING_OBJECT (src, "Invalid hostname '%s' for filesrc", hostname);
g_set_error (err, GST_URI_ERROR, GST_URI_ERROR_BAD_URI,
"File URI with invalid hostname '%s'", hostname);
goto beach;
}
#ifdef G_OS_WIN32
/* Unfortunately, g_filename_from_uri() doesn't handle some UNC paths
* correctly on windows, it leaves them with an extra backslash
* at the start if they're of the mozilla-style file://///host/path/file
* form. Correct this.
*/
if (location[0] == '\\' && location[1] == '\\' && location[2] == '\\')
memmove (location, location + 1, strlen (location + 1) + 1);
#endif
ret = gst_file_src_set_location (src, location, err);
beach:
if (location)
g_free (location);
if (hostname)
g_free (hostname);
return ret;
}
static void
gst_file_src_uri_handler_init (gpointer g_iface, gpointer iface_data)
{
GstURIHandlerInterface *iface = (GstURIHandlerInterface *) g_iface;
iface->get_type = gst_file_src_uri_get_type;
iface->get_protocols = gst_file_src_uri_get_protocols;
iface->get_uri = gst_file_src_uri_get_uri;
iface->set_uri = gst_file_src_uri_set_uri;
}