gstreamer/sys/v4l2/v4l2-utils.c
Tim-Philipp Müller 2d6c93efe5 v4l2: fix potential double-free of error debug string
gst_v4l2_clear_error() doesn't work like g_clear_error(), it
doesn't NULLify the pointer, so set freed debug string to NULL
so it doesn't get freed again if gst_v4l2_clear_error() is
called twice on the error.

CID 1362901
2016-07-01 11:54:57 +01:00

202 lines
4.8 KiB
C

/*
* Copyright (C) 2014 Collabora Ltd.
* Author: Nicolas Dufresne <nicolas.dufresne@collabora.co.uk>
*
* 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.
*
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "v4l2-utils.h"
/**************************/
/* Common device iterator */
/**************************/
#if HAVE_GUDEV
#include <gudev/gudev.h>
struct _GstV4l2GUdevIterator
{
GstV4l2Iterator parent;
GList *devices;
GUdevDevice *device;
GUdevClient *client;
};
GstV4l2Iterator *
gst_v4l2_iterator_new (void)
{
static const gchar *subsystems[] = { "video4linux", NULL };
struct _GstV4l2GUdevIterator *it;
it = g_slice_new0 (struct _GstV4l2GUdevIterator);
it->client = g_udev_client_new (subsystems);
it->devices = g_udev_client_query_by_subsystem (it->client, "video4linux");
return (GstV4l2Iterator *) it;
}
gboolean
gst_v4l2_iterator_next (GstV4l2Iterator * _it)
{
struct _GstV4l2GUdevIterator *it = (struct _GstV4l2GUdevIterator *) _it;
const gchar *device_name;
if (it->device)
g_object_unref (it->device);
it->device = NULL;
it->parent.device_path = NULL;
it->parent.device_name = NULL;
if (it->devices == NULL)
return FALSE;
it->device = it->devices->data;
it->devices = g_list_delete_link (it->devices, it->devices);
device_name = g_udev_device_get_property (it->device, "ID_V4L_PRODUCT");
if (!device_name)
device_name = g_udev_device_get_property (it->device, "ID_MODEL_ENC");
if (!device_name)
device_name = g_udev_device_get_property (it->device, "ID_MODEL");
it->parent.device_path = g_udev_device_get_device_file (it->device);
it->parent.device_name = device_name;
it->parent.sys_path = g_udev_device_get_sysfs_path (it->device);
return TRUE;
}
void
gst_v4l2_iterator_free (GstV4l2Iterator * _it)
{
struct _GstV4l2GUdevIterator *it = (struct _GstV4l2GUdevIterator *) _it;
g_list_free_full (it->devices, g_object_unref);
gst_object_unref (it->client);
g_slice_free (struct _GstV4l2GUdevIterator, it);
}
#else /* No GUDEV */
struct _GstV4l2FsIterator
{
GstV4l2Iterator parent;
gint base_idx;
gint video_idx;
gchar *device;
};
GstV4l2Iterator *
gst_v4l2_iterator_new (void)
{
struct _GstV4l2FsIterator *it;
it = g_slice_new0 (struct _GstV4l2FsIterator);
it->base_idx = 0;
it->video_idx = -1;
it->device = NULL;
return (GstV4l2Iterator *) it;
}
gboolean
gst_v4l2_iterator_next (GstV4l2Iterator * _it)
{
struct _GstV4l2FsIterator *it = (struct _GstV4l2FsIterator *) _it;
static const gchar *dev_base[] = { "/dev/video", "/dev/v4l2/video", NULL };
gchar *device = NULL;
g_free ((gchar *) it->parent.device_path);
it->parent.device_path = NULL;
while (device == NULL) {
it->video_idx++;
if (it->video_idx >= 64) {
it->video_idx = 0;
it->base_idx++;
}
if (dev_base[it->base_idx] == NULL) {
it->video_idx = 0;
break;
}
device = g_strdup_printf ("%s%d", dev_base[it->base_idx], it->video_idx);
if (g_file_test (device, G_FILE_TEST_EXISTS)) {
it->parent.device_path = device;
break;
}
g_free (device);
device = NULL;
}
return it->parent.device_path != NULL;
}
void
gst_v4l2_iterator_free (GstV4l2Iterator * _it)
{
struct _GstV4l2FsIterator *it = (struct _GstV4l2FsIterator *) _it;
g_free ((gchar *) it->parent.device_path);
g_slice_free (struct _GstV4l2FsIterator, it);
}
#endif
void
gst_v4l2_clear_error (GstV4l2Error * v4l2err)
{
if (v4l2err) {
g_clear_error (&v4l2err->error);
g_free (v4l2err->dbg_message);
v4l2err->dbg_message = NULL;
}
}
void
gst_v4l2_error (gpointer element, GstV4l2Error * v4l2err)
{
GError *error;
if (!v4l2err || !v4l2err->error)
return;
error = v4l2err->error;
if (error->message)
GST_WARNING_OBJECT (element, "error: %s", error->message);
if (v4l2err->dbg_message)
GST_WARNING_OBJECT (element, "error: %s", v4l2err->dbg_message);
gst_element_message_full (GST_ELEMENT (element), GST_MESSAGE_ERROR,
error->domain, error->code, error->message, v4l2err->dbg_message,
v4l2err->file, v4l2err->func, v4l2err->line);
error->message = NULL;
v4l2err->dbg_message = NULL;
gst_v4l2_clear_error (v4l2err);
}