/* [<][>][^][v][top][bottom][index][help] */
DEFINITIONS
This source file includes following definitions.
- gst_parse_error_quark
- gst_parse_context_new
- gst_parse_context_free
- gst_parse_context_get_missing_elements
- _gst_parse_escape
- gst_parse_launchv
- gst_parse_launchv_full
- gst_parse_launch
- gst_parse_launch_full
/* GStreamer
* Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
* 2000 Wim Taymans <wtay@chello.be>
* 2002 Andy Wingo <wingo@pobox.com>
* 2008 Tim-Philipp Müller <tim centricular net>
*
* gstparse.c: get a pipeline from a text pipeline description
*
* 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., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/**
* SECTION:gstparse
* @short_description: Get a pipeline from a text pipeline description
*
* These function allow to create a pipeline based on the syntax used in the
* gst-launch utility.
*/
#include "gst_private.h"
#include <string.h>
#include "gstparse.h"
#include "gsterror.h"
#include "gstinfo.h"
#ifndef GST_DISABLE_PARSE
#include "parse/types.h"
#endif
/**
* gst_parse_error_quark:
*
* Get the error quark used by the parsing subsystem.
*
* Returns: the quark of the parse errors.
*/
GQuark
gst_parse_error_quark (void)
{
static GQuark quark = 0;
if (!quark)
quark = g_quark_from_static_string ("gst_parse_error");
return quark;
}
/**
* gst_parse_context_new:
*
* Allocates a parse context for use with gst_parse_launch_full() or
* gst_parse_launchv_full().
*
* Returns: a newly-allocated parse context. Free with gst_parse_context_free()
* when no longer needed.
*
* Since: 0.10.20
*/
GstParseContext *
gst_parse_context_new (void)
{
#ifndef GST_DISABLE_PARSE
GstParseContext *ctx;
ctx = g_slice_new (GstParseContext);
ctx->missing_elements = NULL;
return ctx;
#else
return NULL;
#endif
}
/**
* gst_parse_context_free:
* @context: a #GstParseContext
*
* Frees a parse context previously allocated with gst_parse_context_new().
*
* Since: 0.10.20
*/
void
gst_parse_context_free (GstParseContext * context)
{
#ifndef GST_DISABLE_PARSE
if (context) {
g_list_foreach (context->missing_elements, (GFunc) g_free, NULL);
g_list_free (context->missing_elements);
g_slice_free (GstParseContext, context);
}
#endif
}
/**
* gst_parse_context_get_missing_elements:
* @context: a #GstParseContext
*
* Retrieve missing elements from a previous run of gst_parse_launch_full()
* or gst_parse_launchv_full(). Will only return results if an error code
* of %GST_PARSE_ERROR_NO_SUCH_ELEMENT was returned.
*
* Returns: a NULL-terminated array of element factory name strings of
* missing elements. Free with g_strfreev() when no longer needed.
*
* Since: 0.10.20
*/
gchar **
gst_parse_context_get_missing_elements (GstParseContext * context)
{
#ifndef GST_DISABLE_PARSE
gchar **arr;
GList *l;
guint len, i;
g_return_val_if_fail (context != NULL, NULL);
len = g_list_length (context->missing_elements);
if (G_UNLIKELY (len == 0))
return NULL;
arr = g_new (gchar *, len + 1);
for (i = 0, l = context->missing_elements; l != NULL; l = l->next, ++i)
arr[i] = g_strdup (l->data);
arr[i] = NULL;
return arr;
#else
return NULL;
#endif
}
#ifndef GST_DISABLE_PARSE
static gchar *
_gst_parse_escape (const gchar * str)
{
GString *gstr = NULL;
g_return_val_if_fail (str != NULL, NULL);
gstr = g_string_sized_new (strlen (str));
while (*str) {
if (*str == ' ')
g_string_append_c (gstr, '\\');
g_string_append_c (gstr, *str);
str++;
}
return g_string_free (gstr, FALSE);
}
#endif /* !GST_DISABLE_PARSE */
/**
* gst_parse_launchv:
* @argv: null-terminated array of arguments
* @error: pointer to a #GError
*
* Create a new element based on command line syntax.
* @error will contain an error message if an erroneuos pipeline is specified.
* An error does not mean that the pipeline could not be constructed.
*
* Returns: a new element on success and %NULL on failure.
*/
GstElement *
gst_parse_launchv (const gchar ** argv, GError ** error)
{
return gst_parse_launchv_full (argv, NULL, 0, error);
}
/**
* gst_parse_launchv_full:
* @argv: null-terminated array of arguments
* @context: a parse context allocated with gst_parse_context_new(), or %NULL
* @flags: parsing options, or #GST_PARSE_FLAG_NONE
* @error: pointer to a #GError (which must be initialised to %NULL)
*
* Create a new element based on command line syntax.
* @error will contain an error message if an erroneous pipeline is specified.
* An error does not mean that the pipeline could not be constructed.
*
* Returns: a new element on success; on failure, either %NULL or a
* partially-constructed bin or element will be returned and @error will be set
* (unless you passed #GST_PARSE_FLAG_FATAL_ERRORS in @flags, then %NULL will
* always be returned on failure)
*
* Since: 0.10.20
*/
GstElement *
gst_parse_launchv_full (const gchar ** argv, GstParseContext * context,
GstParseFlags flags, GError ** error)
{
#ifndef GST_DISABLE_PARSE
GstElement *element;
GString *str;
const gchar **argvp, *arg;
gchar *tmp;
g_return_val_if_fail (argv != NULL, NULL);
g_return_val_if_fail (error == NULL || *error == NULL, NULL);
/* let's give it a nice size. */
str = g_string_sized_new (1024);
argvp = argv;
while (*argvp) {
arg = *argvp;
tmp = _gst_parse_escape (arg);
g_string_append (str, tmp);
g_free (tmp);
g_string_append_c (str, ' ');
argvp++;
}
element = gst_parse_launch_full (str->str, context, flags, error);
g_string_free (str, TRUE);
return element;
#else
/* gst_parse_launch_full() will set a GST_CORE_ERROR_DISABLED error for us */
return gst_parse_launch_full ("", NULL, 0, error);
#endif
}
/**
* gst_parse_launch:
* @pipeline_description: the command line describing the pipeline
* @error: the error message in case of an erroneous pipeline.
*
* Create a new pipeline based on command line syntax.
* Please note that you might get a return value that is not %NULL even though
* the @error is set. In this case there was a recoverable parsing error and you
* can try to play the pipeline.
*
* Returns: a new element on success, %NULL on failure. If more than one toplevel
* element is specified by the @pipeline_description, all elements are put into
* a #GstPipeline, which than is returned.
*/
GstElement *
gst_parse_launch (const gchar * pipeline_description, GError ** error)
{
return gst_parse_launch_full (pipeline_description, NULL, 0, error);
}
/**
* gst_parse_launch_full:
* @pipeline_description: the command line describing the pipeline
* @context: a parse context allocated with gst_parse_context_new(), or %NULL
* @flags: parsing options, or #GST_PARSE_FLAG_NONE
* @error: the error message in case of an erroneous pipeline.
*
* Create a new pipeline based on command line syntax.
* Please note that you might get a return value that is not %NULL even though
* the @error is set. In this case there was a recoverable parsing error and you
* can try to play the pipeline.
*
* Returns: a new element on success, %NULL on failure. If more than one toplevel
* element is specified by the @pipeline_description, all elements are put into
* a #GstPipeline, which then is returned.
*
* Since: 0.10.20
*/
GstElement *
gst_parse_launch_full (const gchar * pipeline_description,
GstParseContext * context, GstParseFlags flags, GError ** error)
{
#ifndef GST_DISABLE_PARSE
GstElement *element;
g_return_val_if_fail (pipeline_description != NULL, NULL);
g_return_val_if_fail (error == NULL || *error == NULL, NULL);
GST_CAT_INFO (GST_CAT_PIPELINE, "parsing pipeline description '%s'",
pipeline_description);
element = _gst_parse_launch (pipeline_description, error, context, flags);
/* don't return partially constructed pipeline if FATAL_ERRORS was given */
if (G_UNLIKELY (error != NULL && *error != NULL && element != NULL)) {
if ((flags & GST_PARSE_FLAG_FATAL_ERRORS)) {
gst_object_unref (element);
element = NULL;
}
}
return element;
#else
gchar *msg;
GST_WARNING ("Disabled API called");
msg = gst_error_get_message (GST_CORE_ERROR, GST_CORE_ERROR_DISABLED);
g_set_error (error, GST_CORE_ERROR, GST_CORE_ERROR_DISABLED, "%s", msg);
g_free (msg);
return NULL;
#endif
}