* 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
*
*
* 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.
+ * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
*/
+/**
+ * SECTION:gstparse
+ * @title: 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-1.0 utility (see man-page for syntax documentation).
+ *
+ * Please note that these functions take several measures to create
+ * somewhat dynamic pipelines. Due to that such pipelines are not always
+ * reusable (set the state to NULL and back to PLAYING).
+ */
+
+#include "gst_private.h"
#include <string.h>
#include "gstparse.h"
+#include "gsterror.h"
#include "gstinfo.h"
-#include "gstlog.h"
+#ifndef GST_DISABLE_PARSE
+#include "parse/types.h"
+#endif
-extern GstElement *_gst_parse_launch (const gchar *, GError **);
+G_DEFINE_BOXED_TYPE (GstParseContext, gst_parse_context,
+ (GBoxedCopyFunc) gst_parse_context_copy,
+ (GBoxedFreeFunc) gst_parse_context_free);
-GQuark
+/**
+ * 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;
}
-static gchar *_gst_parse_escape (const gchar *str)
+
+/**
+ * gst_parse_context_new:
+ *
+ * Allocates a parse context for use with gst_parse_launch_full() or
+ * gst_parse_launchv_full().
+ *
+ * Free-function: gst_parse_context_free
+ *
+ * Returns: (transfer full) (nullable): a newly-allocated parse context. Free
+ * with gst_parse_context_free() when no longer needed.
+ */
+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_copy:
+ * @context: a #GstParseContext
+ *
+ * Copies the @context.
+ *
+ * Returns: (transfer full) (nullable): A copied #GstParseContext
+ */
+GstParseContext *
+gst_parse_context_copy (const GstParseContext * context)
+{
+ GstParseContext *ret = NULL;
+#ifndef GST_DISABLE_PARSE
+
+ ret = gst_parse_context_new ();
+ if (context) {
+ GQueue missing_copy = G_QUEUE_INIT;
+ GList *l;
+
+ for (l = context->missing_elements; l != NULL; l = l->next)
+ g_queue_push_tail (&missing_copy, g_strdup ((const gchar *) l->data));
+
+ ret->missing_elements = missing_copy.head;
+ }
+#endif
+ return ret;
+}
+
+/**
+ * gst_parse_context_free:
+ * @context: (transfer full): a #GstParseContext
+ *
+ * Frees a parse context previously allocated with gst_parse_context_new().
+ */
+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: (transfer full) (array zero-terminated=1) (element-type gchar*) (nullable): a
+ * %NULL-terminated array of element factory name strings of missing
+ * elements. Free with g_strfreev() when no longer needed.
+ */
+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;
-
+ gboolean in_quotes;
+
g_return_val_if_fail (str != NULL, NULL);
-
+
gstr = g_string_sized_new (strlen (str));
-
+
+ in_quotes = FALSE;
+
while (*str) {
- if (*str == ' ')
+ if (*str == '"' && (!in_quotes || *(str - 1) != '\\'))
+ in_quotes = !in_quotes;
+
+ if (*str == ' ' && !in_quotes)
g_string_append_c (gstr, '\\');
+
g_string_append_c (gstr, *str);
str++;
}
-
- return gstr->str;
+
+ return g_string_free (gstr, FALSE);
}
+#endif /* !GST_DISABLE_PARSE */
+
/**
* gst_parse_launchv:
- * @argv: null-terminated array of arguments
+ * @argv: (in) (array zero-terminated=1): 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 pipeline creation fails and can
- * contain an error message, when a recoverable error happened.
+ * @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 and NULL on failure.
+ * Returns: (transfer floating) (nullable): a new element on success and %NULL
+ * on failure.
*/
GstElement *
-gst_parse_launchv (const gchar **argv, GError **error)
+gst_parse_launchv (const gchar ** argv, GError ** error)
{
+ return gst_parse_launchv_full (argv, NULL, GST_PARSE_FLAG_NONE, error);
+}
+
+/**
+ * gst_parse_launchv_full:
+ * @argv: (in) (array zero-terminated=1): null-terminated array of arguments
+ * @context: (allow-none): 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: (transfer floating) (nullable): 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)
+ */
+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;
+ GST_DEBUG ("escaping argument %s", arg);
tmp = _gst_parse_escape (arg);
g_string_append (str, tmp);
g_free (tmp);
- g_string_append (str, " ");
+ g_string_append_c (str, ' ');
argvp++;
}
-
- element = gst_parse_launch (str->str, error);
+
+ 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 a failure
+ * @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 bin on success, NULL on failure. By default the bin is
- * a GstPipeline, but it depends on the pipeline_description.
+ * Returns: (transfer floating) (nullable): 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)
+gst_parse_launch (const gchar * pipeline_description, GError ** error)
{
+ return gst_parse_launch_full (pipeline_description, NULL, GST_PARSE_FLAG_NONE,
+ error);
+}
+
+/**
+ * gst_parse_launch_full:
+ * @pipeline_description: the command line describing the pipeline
+ * @context: (allow-none): 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: (transfer floating) (nullable): 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 (unless the GST_PARSE_FLAG_PLACE_IN_BIN flag is set, in
+ * which case they are put in a #GstBin instead).
+ */
+GstElement *
+gst_parse_launch_full (const gchar * pipeline_description,
+ GstParseContext * context, GstParseFlags flags, GError ** error)
+{
+#ifndef GST_DISABLE_PARSE
GstElement *element;
- static GStaticMutex flex_lock = G_STATIC_MUTEX_INIT;
+ GError *myerror = NULL;
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);
- GST_INFO (GST_CAT_PIPELINE, "parsing pipeline description %s",
- pipeline_description);
+ element = priv_gst_parse_launch (pipeline_description, &myerror, context,
+ flags);
- /* the need for the mutex will go away with flex 2.5.6 */
- g_static_mutex_lock (&flex_lock);
- element = _gst_parse_launch (pipeline_description, error);
- g_static_mutex_unlock (&flex_lock);
+ /* don't return partially constructed pipeline if FATAL_ERRORS was given */
+ if (G_UNLIKELY (myerror != NULL && element != NULL)) {
+ if ((flags & GST_PARSE_FLAG_FATAL_ERRORS)) {
+ gst_object_unref (element);
+ element = NULL;
+ }
+ }
+
+ if (myerror)
+ g_propagate_error (error, myerror);
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
}