mirror of
https://gitlab.freedesktop.org/gstreamer/gstreamer.git
synced 2024-09-08 13:18:52 +00:00
new "Electric Fence" element, that converts each buffer into an allocated region surrounded by two unmapped pages.
Original commit message from CVS: new "Electric Fence" element, that converts each buffer into an allocated region surrounded by two unmapped pages.
This commit is contained in:
parent
d1b4db094c
commit
3d3cec6e7e
3 changed files with 494 additions and 0 deletions
11
gst/debug/Makefile.am
Normal file
11
gst/debug/Makefile.am
Normal file
|
@ -0,0 +1,11 @@
|
|||
plugindir= $(libdir)/gstreamer-@GST_MAJORMINOR@
|
||||
|
||||
plugin_LTLIBRARIES = libgstefence.la
|
||||
|
||||
noinst_HEADERS = efence.h
|
||||
|
||||
libgstefence_la_SOURCES = efence.c
|
||||
|
||||
libgstefence_la_CFLAGS = $(GST_CFLAGS)
|
||||
libgstefence_la_LDFLAGS = $(GST_LIBS)
|
||||
|
434
gst/debug/efence.c
Normal file
434
gst/debug/efence.c
Normal file
|
@ -0,0 +1,434 @@
|
|||
/*
|
||||
* GStreamer
|
||||
* Copyright (C) 1999-2001 Erik Walthinsen <omega@cse.ogi.edu>
|
||||
* Copyright (C) 2002 David A. Schleef <ds@schleef.org>
|
||||
*
|
||||
* 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.
|
||||
*/
|
||||
|
||||
#include <gst/gst.h>
|
||||
|
||||
#include <string.h>
|
||||
#include <unistd.h>
|
||||
#include <sys/mman.h>
|
||||
|
||||
#include "efence.h"
|
||||
|
||||
static GstElementDetails plugin_details = {
|
||||
"Electric Fence",
|
||||
"Testing/EFence",
|
||||
"LGPL",
|
||||
"This element converts a stream of normal GStreamer buffers into a "
|
||||
"stream of buffers that are allocated in such a way that out-of-bounds "
|
||||
"access to data in the buffer is more likely to cause segmentation "
|
||||
"faults. This allocation method is very similar to the debugging tool "
|
||||
"\"Electric Fence\".",
|
||||
VERSION,
|
||||
"David A. Schleef <ds@schleef.org>",
|
||||
"(C) 2002, 2003"
|
||||
};
|
||||
|
||||
/* Filter signals and args */
|
||||
enum {
|
||||
/* FILL ME */
|
||||
LAST_SIGNAL
|
||||
};
|
||||
|
||||
enum {
|
||||
ARG_0,
|
||||
ARG_FENCE_TOP
|
||||
};
|
||||
|
||||
GST_PAD_TEMPLATE_FACTORY (gst_efence_sink_factory,
|
||||
"sink",
|
||||
GST_PAD_SINK,
|
||||
GST_PAD_ALWAYS,
|
||||
NULL /* no caps */
|
||||
);
|
||||
|
||||
GST_PAD_TEMPLATE_FACTORY (gst_efence_src_factory,
|
||||
"src",
|
||||
GST_PAD_SRC,
|
||||
GST_PAD_ALWAYS,
|
||||
NULL /* no caps */
|
||||
);
|
||||
|
||||
static void gst_efence_class_init (GstEFenceClass *klass);
|
||||
static void gst_efence_init (GstEFence *filter);
|
||||
|
||||
static void gst_efence_set_property(GObject *object, guint prop_id,
|
||||
const GValue *value,
|
||||
GParamSpec *pspec);
|
||||
static void gst_efence_get_property(GObject *object, guint prop_id,
|
||||
GValue *value,
|
||||
GParamSpec *pspec);
|
||||
|
||||
static void gst_efence_chain (GstPad *pad, GstBuffer *buf);
|
||||
|
||||
static GstElementClass *parent_class = NULL;
|
||||
|
||||
typedef struct _GstFencedBuffer GstFencedBuffer;
|
||||
struct _GstFencedBuffer {
|
||||
GstBuffer buffer;
|
||||
void *region;
|
||||
unsigned int length;
|
||||
};
|
||||
|
||||
void gst_fenced_buffer_default_free (GstBuffer *buffer);
|
||||
GstBuffer* gst_fenced_buffer_default_copy (GstBuffer *buffer);
|
||||
void *gst_fenced_buffer_alloc(GstBuffer *buffer, unsigned int length,
|
||||
gboolean fence_top);
|
||||
|
||||
GstBuffer *gst_fenced_buffer_new(void);
|
||||
|
||||
static GstPadLinkReturn
|
||||
gst_efence_link (GstPad *pad, GstCaps *caps)
|
||||
{
|
||||
GstEFence *filter;
|
||||
GstPad *otherpad;
|
||||
|
||||
filter = GST_EFENCE (gst_pad_get_parent (pad));
|
||||
g_return_val_if_fail (filter != NULL, GST_PAD_LINK_REFUSED);
|
||||
g_return_val_if_fail (GST_IS_EFENCE (filter),
|
||||
GST_PAD_LINK_REFUSED);
|
||||
otherpad = (pad == filter->srcpad ? filter->sinkpad : filter->srcpad);
|
||||
|
||||
if (GST_CAPS_IS_FIXED (caps))
|
||||
{
|
||||
/* caps are not fixed, so try to link on the other side and see if
|
||||
* that works */
|
||||
|
||||
if (!gst_pad_try_set_caps (otherpad, caps))
|
||||
return GST_PAD_LINK_REFUSED;
|
||||
|
||||
/* caps on other side were accepted, so we're ok */
|
||||
return GST_PAD_LINK_OK;
|
||||
}
|
||||
/* not enough information yet, delay negotation */
|
||||
return GST_PAD_LINK_DELAYED;
|
||||
}
|
||||
|
||||
GType
|
||||
gst_gst_efence_get_type (void)
|
||||
{
|
||||
static GType plugin_type = 0;
|
||||
|
||||
if (!plugin_type)
|
||||
{
|
||||
static const GTypeInfo plugin_info =
|
||||
{
|
||||
sizeof (GstEFenceClass),
|
||||
NULL,
|
||||
NULL,
|
||||
(GClassInitFunc) gst_efence_class_init,
|
||||
NULL,
|
||||
NULL,
|
||||
sizeof (GstEFence),
|
||||
0,
|
||||
(GInstanceInitFunc) gst_efence_init,
|
||||
};
|
||||
plugin_type = g_type_register_static (GST_TYPE_ELEMENT,
|
||||
"GstEFence",
|
||||
&plugin_info, 0);
|
||||
}
|
||||
return plugin_type;
|
||||
}
|
||||
|
||||
/* initialize the plugin's class */
|
||||
static void
|
||||
gst_efence_class_init (GstEFenceClass *klass)
|
||||
{
|
||||
GObjectClass *gobject_class;
|
||||
GstElementClass *gstelement_class;
|
||||
|
||||
gobject_class = (GObjectClass*) klass;
|
||||
gstelement_class = (GstElementClass*) klass;
|
||||
|
||||
parent_class = g_type_class_ref (GST_TYPE_ELEMENT);
|
||||
|
||||
g_object_class_install_property (gobject_class, ARG_FENCE_TOP,
|
||||
g_param_spec_boolean ("fence_top", "Fence Top", "Align buffers with top of fenced region",
|
||||
TRUE, G_PARAM_READWRITE));
|
||||
|
||||
gobject_class->set_property = gst_efence_set_property;
|
||||
gobject_class->get_property = gst_efence_get_property;
|
||||
}
|
||||
|
||||
/* initialize the new element
|
||||
* instantiate pads and add them to element
|
||||
* set functions
|
||||
* initialize structure
|
||||
*/
|
||||
static void
|
||||
gst_efence_init (GstEFence *filter)
|
||||
{
|
||||
filter->sinkpad = gst_pad_new_from_template (gst_efence_sink_factory (),
|
||||
"sink");
|
||||
gst_pad_set_link_function (filter->sinkpad, gst_efence_link);
|
||||
filter->srcpad = gst_pad_new_from_template (gst_efence_src_factory (),
|
||||
"src");
|
||||
gst_pad_set_link_function (filter->srcpad, gst_efence_link);
|
||||
|
||||
gst_element_add_pad (GST_ELEMENT (filter), filter->sinkpad);
|
||||
gst_element_add_pad (GST_ELEMENT (filter), filter->srcpad);
|
||||
gst_pad_set_chain_function (filter->sinkpad, gst_efence_chain);
|
||||
|
||||
filter->fence_top = TRUE;
|
||||
}
|
||||
|
||||
/* chain function
|
||||
* this function does the actual processing
|
||||
*/
|
||||
|
||||
static void
|
||||
gst_efence_chain (GstPad *pad, GstBuffer *buffer)
|
||||
{
|
||||
GstEFence *efence;
|
||||
GstBuffer *copy;
|
||||
void *ptr;
|
||||
|
||||
GST_DEBUG(0, "gst_efence_chain");
|
||||
|
||||
g_return_if_fail (GST_IS_PAD (pad));
|
||||
g_return_if_fail (buffer != NULL);
|
||||
|
||||
efence = GST_EFENCE (GST_OBJECT_PARENT (pad));
|
||||
g_return_if_fail (GST_IS_EFENCE (efence));
|
||||
|
||||
copy = gst_fenced_buffer_new();
|
||||
|
||||
ptr = gst_fenced_buffer_alloc(copy, GST_BUFFER_SIZE(buffer),
|
||||
efence->fence_top);
|
||||
memcpy(ptr, GST_BUFFER_DATA(buffer), GST_BUFFER_SIZE(buffer));
|
||||
|
||||
GST_BUFFER_DATA (copy) = ptr;
|
||||
GST_BUFFER_SIZE (copy) = GST_BUFFER_SIZE (buffer);
|
||||
GST_BUFFER_MAXSIZE (copy) = GST_BUFFER_SIZE (buffer);
|
||||
GST_BUFFER_TIMESTAMP (copy) = GST_BUFFER_TIMESTAMP (buffer);
|
||||
GST_BUFFER_DURATION (copy) = GST_BUFFER_DURATION (buffer);
|
||||
GST_BUFFER_OFFSET (copy) = GST_BUFFER_OFFSET (buffer);
|
||||
GST_BUFFER_BUFFERPOOL (copy) = NULL;
|
||||
GST_BUFFER_POOL_PRIVATE (copy) = NULL;
|
||||
|
||||
gst_buffer_unref(buffer);
|
||||
gst_pad_push (efence->srcpad, copy);
|
||||
}
|
||||
|
||||
static void
|
||||
gst_efence_set_property (GObject *object, guint prop_id,
|
||||
const GValue *value, GParamSpec *pspec)
|
||||
{
|
||||
GstEFence *filter;
|
||||
|
||||
g_return_if_fail (GST_IS_EFENCE (object));
|
||||
filter = GST_EFENCE (object);
|
||||
|
||||
switch (prop_id)
|
||||
{
|
||||
case ARG_FENCE_TOP:
|
||||
filter->fence_top = g_value_get_boolean (value);
|
||||
break;
|
||||
default:
|
||||
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
static void
|
||||
gst_efence_get_property (GObject *object, guint prop_id,
|
||||
GValue *value, GParamSpec *pspec)
|
||||
{
|
||||
GstEFence *filter;
|
||||
|
||||
g_return_if_fail (GST_IS_EFENCE (object));
|
||||
filter = GST_EFENCE (object);
|
||||
|
||||
switch (prop_id) {
|
||||
case ARG_FENCE_TOP:
|
||||
g_value_set_boolean (value, filter->fence_top);
|
||||
break;
|
||||
default:
|
||||
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
/* entry point to initialize the plug-in
|
||||
* initialize the plug-in itself
|
||||
* register the element factories and pad templates
|
||||
* register the features
|
||||
*/
|
||||
static gboolean
|
||||
plugin_init (GModule *module, GstPlugin *plugin)
|
||||
{
|
||||
GstElementFactory *factory;
|
||||
|
||||
factory = gst_element_factory_new ("efence", GST_TYPE_EFENCE,
|
||||
&plugin_details);
|
||||
g_return_val_if_fail (factory != NULL, FALSE);
|
||||
|
||||
gst_element_factory_add_pad_template (factory,
|
||||
gst_efence_src_factory ());
|
||||
gst_element_factory_add_pad_template (factory,
|
||||
gst_efence_sink_factory ());
|
||||
|
||||
gst_plugin_add_feature (plugin, GST_PLUGIN_FEATURE (factory));
|
||||
|
||||
/* plugin initialisation succeeded */
|
||||
return TRUE;
|
||||
}
|
||||
|
||||
/* this is the structure that gst-register looks for
|
||||
* so keep the name plugin_desc, or you cannot get your plug-in registered */
|
||||
GstPluginDesc plugin_desc = {
|
||||
GST_VERSION_MAJOR,
|
||||
GST_VERSION_MINOR,
|
||||
"efence",
|
||||
plugin_init
|
||||
};
|
||||
|
||||
|
||||
|
||||
|
||||
GstBuffer *gst_fenced_buffer_new(void)
|
||||
{
|
||||
GstBuffer *newbuf;
|
||||
|
||||
newbuf = (GstBuffer *) g_new0(GstFencedBuffer,1);
|
||||
|
||||
gst_data_init (GST_DATA (newbuf), _gst_buffer_type, 0,
|
||||
(GstDataFreeFunction) gst_fenced_buffer_default_free,
|
||||
(GstDataCopyFunction) gst_fenced_buffer_default_copy);
|
||||
|
||||
GST_BUFFER_DATA (newbuf) = NULL;
|
||||
GST_BUFFER_SIZE (newbuf) = 0;
|
||||
GST_BUFFER_MAXSIZE (newbuf) = GST_BUFFER_MAXSIZE_NONE;
|
||||
GST_BUFFER_TIMESTAMP (newbuf) = GST_CLOCK_TIME_NONE;
|
||||
GST_BUFFER_DURATION (newbuf) = GST_CLOCK_TIME_NONE;
|
||||
GST_BUFFER_OFFSET (newbuf) = GST_BUFFER_OFFSET_NONE;
|
||||
GST_BUFFER_BUFFERPOOL (newbuf) = NULL;
|
||||
GST_BUFFER_POOL_PRIVATE (newbuf) = NULL;
|
||||
|
||||
GST_DEBUG(0, "new buffer=%p", newbuf);
|
||||
|
||||
return newbuf;
|
||||
}
|
||||
|
||||
void gst_fenced_buffer_default_free (GstBuffer *buffer)
|
||||
{
|
||||
GstFencedBuffer *fenced_buffer;
|
||||
|
||||
GST_DEBUG(0, "free buffer=%p", buffer);
|
||||
|
||||
g_return_if_fail (buffer != NULL);
|
||||
|
||||
fenced_buffer = (GstFencedBuffer *) buffer;
|
||||
|
||||
/* free our data */
|
||||
if (!GST_BUFFER_FLAG_IS_SET (buffer, GST_BUFFER_DONTFREE) &&
|
||||
GST_BUFFER_DATA (buffer)) {
|
||||
GST_DEBUG(0, "free region %p %d", fenced_buffer->region,
|
||||
fenced_buffer->length);
|
||||
munmap(fenced_buffer->region, fenced_buffer->length);
|
||||
}else{
|
||||
GST_DEBUG(0, "not freeing region %p %d %p", fenced_buffer->region,
|
||||
GST_BUFFER_FLAGS(buffer), GST_BUFFER_DATA(buffer));
|
||||
}
|
||||
|
||||
/* set to safe values */
|
||||
GST_BUFFER_DATA (buffer) = NULL;
|
||||
GST_BUFFER_SIZE (buffer) = 0;
|
||||
|
||||
g_free (buffer);
|
||||
}
|
||||
|
||||
GstBuffer* gst_fenced_buffer_default_copy (GstBuffer *buffer)
|
||||
{
|
||||
GstBuffer *copy;
|
||||
void *ptr;
|
||||
|
||||
g_return_val_if_fail (buffer != NULL, NULL);
|
||||
|
||||
/* create a fresh new buffer */
|
||||
copy = (GstBuffer *) g_new0(GstFencedBuffer,1);
|
||||
|
||||
gst_data_init (GST_DATA (copy), _gst_buffer_type, 0,
|
||||
(GstDataFreeFunction) gst_fenced_buffer_default_free,
|
||||
(GstDataCopyFunction) gst_fenced_buffer_default_copy);
|
||||
|
||||
/* we simply copy everything from our parent */
|
||||
ptr = gst_fenced_buffer_alloc(copy, GST_BUFFER_SIZE(buffer), TRUE);
|
||||
memcpy(ptr, GST_BUFFER_DATA(buffer), GST_BUFFER_SIZE(buffer));
|
||||
|
||||
GST_BUFFER_SIZE (copy) = GST_BUFFER_SIZE (buffer);
|
||||
GST_BUFFER_MAXSIZE (copy) = GST_BUFFER_SIZE (buffer);
|
||||
GST_BUFFER_TIMESTAMP (copy) = GST_BUFFER_TIMESTAMP (buffer);
|
||||
GST_BUFFER_DURATION (copy) = GST_BUFFER_DURATION (buffer);
|
||||
GST_BUFFER_OFFSET (copy) = GST_BUFFER_OFFSET (buffer);
|
||||
GST_BUFFER_BUFFERPOOL (copy) = NULL;
|
||||
GST_BUFFER_POOL_PRIVATE (copy) = NULL;
|
||||
|
||||
return copy;
|
||||
}
|
||||
|
||||
void *gst_fenced_buffer_alloc(GstBuffer *buffer, unsigned int length,
|
||||
gboolean fence_top)
|
||||
{
|
||||
int alloc_size;
|
||||
void *region;
|
||||
GstFencedBuffer *fenced_buffer = (GstFencedBuffer *) buffer;
|
||||
int page_size;
|
||||
|
||||
GST_DEBUG(0, "buffer=%p length=%d fence_top=%d", buffer, length, fence_top);
|
||||
|
||||
if(length==0)return NULL;
|
||||
|
||||
#ifdef _SC_PAGESIZE
|
||||
page_size = sysconf(_SC_PAGESIZE);
|
||||
#else
|
||||
page_size = getpagesize();
|
||||
#endif
|
||||
|
||||
alloc_size = ((length - 1) & ~(page_size - 1)) + page_size;
|
||||
alloc_size += 2*page_size;
|
||||
|
||||
region = mmap(NULL, alloc_size, PROT_READ|PROT_WRITE,
|
||||
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
|
||||
if(region == MAP_FAILED){
|
||||
g_warning("mmap failed");
|
||||
return NULL;
|
||||
}
|
||||
|
||||
munmap(region, page_size);
|
||||
munmap(region + alloc_size - page_size, page_size);
|
||||
|
||||
fenced_buffer->region = region;
|
||||
fenced_buffer->length = alloc_size;
|
||||
|
||||
GST_DEBUG(0, "new region %p %d", fenced_buffer->region,
|
||||
fenced_buffer->length);
|
||||
|
||||
if(fence_top){
|
||||
int offset;
|
||||
/* Align to top of region, but force alignment to 4 bytes */
|
||||
offset = alloc_size - page_size - length;
|
||||
offset &= ~0x3;
|
||||
return region + offset;
|
||||
}else{
|
||||
return region + page_size;
|
||||
}
|
||||
}
|
||||
|
49
gst/debug/efence.h
Normal file
49
gst/debug/efence.h
Normal file
|
@ -0,0 +1,49 @@
|
|||
/*
|
||||
* efence.h
|
||||
*/
|
||||
|
||||
#ifndef __GST_EFENCE_H__
|
||||
#define __GST_EFENCE_H__
|
||||
|
||||
#include <gst/gst.h>
|
||||
|
||||
#ifdef __cplusplus
|
||||
extern "C" {
|
||||
#endif /* __cplusplus */
|
||||
|
||||
/* #define's don't like whitespacey bits */
|
||||
#define GST_TYPE_EFENCE \
|
||||
(gst_gst_efence_get_type())
|
||||
#define GST_EFENCE(obj) \
|
||||
(G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_EFENCE,GstEFence))
|
||||
#define GST_EFENCE_CLASS(klass) \
|
||||
(G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_EFENCE,GstEFence))
|
||||
#define GST_IS_EFENCE(obj) \
|
||||
(G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_EFENCE))
|
||||
#define GST_IS_EFENCE_CLASS(obj) \
|
||||
(G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_EFENCE))
|
||||
|
||||
typedef struct _GstEFence GstEFence;
|
||||
typedef struct _GstEFenceClass GstEFenceClass;
|
||||
|
||||
struct _GstEFence
|
||||
{
|
||||
GstElement element;
|
||||
|
||||
GstPad *sinkpad, *srcpad;
|
||||
|
||||
gboolean fence_top;
|
||||
};
|
||||
|
||||
struct _GstEFenceClass
|
||||
{
|
||||
GstElementClass parent_class;
|
||||
};
|
||||
|
||||
GType gst_gst_efence_get_type (void);
|
||||
|
||||
#ifdef __cplusplus
|
||||
}
|
||||
#endif /* __cplusplus */
|
||||
|
||||
#endif /* __GST_EFENCE_H__ */
|
Loading…
Reference in a new issue