gstreamer/plugins/elements/gstasyncdisksrc.c

347 lines
10 KiB
C
Raw Normal View History

/* Gnome-Streamer
* Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
*
* 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 <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/mman.h>
#include <gstasyncdisksrc.h>
GstElementDetails gst_asyncdisksrc_details = {
"Asynchronous Disk Source",
"Source/File",
"Read from arbitrary point in a file",
VERSION,
"Erik Walthinsen <omega@cse.ogi.edu>",
"(C) 1999",
};
/* AsyncDiskSrc signals and args */
enum {
/* FILL ME */
LAST_SIGNAL
};
enum {
ARG_0,
ARG_LOCATION,
ARG_BYTESPERREAD,
ARG_LENGTH,
ARG_OFFSET,
};
static void gst_asyncdisksrc_class_init(GstAsyncDiskSrcClass *klass);
static void gst_asyncdisksrc_init(GstAsyncDiskSrc *asyncdisksrc);
static void gst_asyncdisksrc_set_arg(GtkObject *object,GtkArg *arg,guint id);
static void gst_asyncdisksrc_get_arg(GtkObject *object,GtkArg *arg,guint id);
static void gst_asyncdisksrc_push(GstSrc *src);
static void gst_asyncdisksrc_push_region(GstSrc *src,gulong offset,
gulong size);
static gboolean gst_asyncdisksrc_change_state(GstElement *element,
GstElementState state);
static GstSrcClass *parent_class = NULL;
static guint gst_asyncdisksrc_signals[LAST_SIGNAL] = { 0 };
GtkType
gst_asyncdisksrc_get_type(void) {
static GtkType asyncdisksrc_type = 0;
if (!asyncdisksrc_type) {
static const GtkTypeInfo asyncdisksrc_info = {
"GstAsyncDiskSrc",
sizeof(GstAsyncDiskSrc),
sizeof(GstAsyncDiskSrcClass),
(GtkClassInitFunc)gst_asyncdisksrc_class_init,
(GtkObjectInitFunc)gst_asyncdisksrc_init,
(GtkArgSetFunc)gst_asyncdisksrc_set_arg,
(GtkArgGetFunc)gst_asyncdisksrc_get_arg,
(GtkClassInitFunc)NULL,
};
asyncdisksrc_type = gtk_type_unique(GST_TYPE_SRC,&asyncdisksrc_info);
}
return asyncdisksrc_type;
}
static void
gst_asyncdisksrc_class_init(GstAsyncDiskSrcClass *klass) {
GtkObjectClass *gtkobject_class;
GstElementClass *gstelement_class;
GstSrcClass *gstsrc_class;
gtkobject_class = (GtkObjectClass*)klass;
gstelement_class = (GstElementClass*)klass;
gstsrc_class = (GstSrcClass*)klass;
parent_class = gtk_type_class(GST_TYPE_SRC);
gtk_object_add_arg_type("GstAsyncDiskSrc::location", GTK_TYPE_STRING,
GTK_ARG_READWRITE, ARG_LOCATION);
gtk_object_add_arg_type("GstAsyncDiskSrc::bytesperread", GTK_TYPE_INT,
GTK_ARG_READWRITE, ARG_BYTESPERREAD);
gtk_object_add_arg_type("GstAsyncDiskSrc::length", GTK_TYPE_LONG,
GTK_ARG_READABLE, ARG_LENGTH);
gtk_object_add_arg_type("GstAsyncDiskSrc::offset", GTK_TYPE_LONG,
GTK_ARG_READWRITE, ARG_OFFSET);
gtkobject_class->set_arg = gst_asyncdisksrc_set_arg;
gtkobject_class->get_arg = gst_asyncdisksrc_get_arg;
gstelement_class->change_state = gst_asyncdisksrc_change_state;
gstsrc_class->push = gst_asyncdisksrc_push;
gstsrc_class->push_region = gst_asyncdisksrc_push_region;
}
static void gst_asyncdisksrc_init(GstAsyncDiskSrc *asyncdisksrc) {
GST_SRC_SET_FLAGS(asyncdisksrc,GST_SRC_ASYNC);
asyncdisksrc->srcpad = gst_pad_new("src",GST_PAD_SRC);
gst_element_add_pad(GST_ELEMENT(asyncdisksrc),asyncdisksrc->srcpad);
asyncdisksrc->filename = NULL;
asyncdisksrc->fd = 0;
asyncdisksrc->size = 0;
asyncdisksrc->map = NULL;
asyncdisksrc->curoffset = 0;
asyncdisksrc->bytes_per_read = 4096;
asyncdisksrc->seq = 0;
}
static void gst_asyncdisksrc_set_arg(GtkObject *object,GtkArg *arg,guint id) {
GstAsyncDiskSrc *src;
/* it's not null if we got it, but it might not be ours */
g_return_if_fail(GST_IS_ASYNCDISKSRC(object));
src = GST_ASYNCDISKSRC(object);
switch(id) {
case ARG_LOCATION:
/* the element must be stopped in order to do this */
g_return_if_fail(!GST_FLAG_IS_SET(src,GST_STATE_RUNNING));
if (src->filename) g_free(src->filename);
/* clear the filename if we get a NULL (is that possible?) */
if (GTK_VALUE_STRING(*arg) == NULL) {
src->filename = NULL;
gst_element_set_state(GST_ELEMENT(object),~GST_STATE_COMPLETE);
/* otherwise set the new filename */
} else {
src->filename = g_strdup(GTK_VALUE_STRING(*arg));
gst_element_set_state(GST_ELEMENT(object),GST_STATE_COMPLETE);
}
break;
case ARG_BYTESPERREAD:
src->bytes_per_read = GTK_VALUE_INT(*arg);
break;
case ARG_OFFSET:
src->curoffset = GTK_VALUE_LONG(*arg);
break;
default:
break;
}
}
static void gst_asyncdisksrc_get_arg(GtkObject *object,GtkArg *arg,guint id) {
GstAsyncDiskSrc *src;
/* it's not null if we got it, but it might not be ours */
g_return_if_fail(GST_IS_ASYNCDISKSRC(object));
src = GST_ASYNCDISKSRC(object);
switch (id) {
case ARG_LOCATION:
GTK_VALUE_STRING(*arg) = src->filename;
break;
case ARG_BYTESPERREAD:
GTK_VALUE_INT(*arg) = src->bytes_per_read;
break;
case ARG_LENGTH:
GTK_VALUE_LONG(*arg) = src->size;
break;
case ARG_OFFSET:
GTK_VALUE_LONG(*arg) = src->curoffset;
break;
default:
arg->type = GTK_TYPE_INVALID;
break;
}
}
/**
* gst_asyncdisksrc_push:
* @src: #GstSrc to push a buffer from
*
* Push a new buffer from the asyncdisksrc at the current offset.
*/
void gst_asyncdisksrc_push(GstSrc *src) {
GstAsyncDiskSrc *asyncdisksrc;
GstBuffer *buf;
g_return_if_fail(src != NULL);
g_return_if_fail(GST_IS_ASYNCDISKSRC(src));
g_return_if_fail(GST_FLAG_IS_SET(src,GST_ASYNCDISKSRC_OPEN));
asyncdisksrc = GST_ASYNCDISKSRC(src);
/* deal with EOF state */
if (asyncdisksrc->curoffset >= asyncdisksrc->size) {
gst_src_signal_eos(GST_SRC(asyncdisksrc));
return;
}
/* create the buffer */
// FIXME: should eventually use a bufferpool for this
buf = GST_BUFFER(gst_buffer_new());
g_return_if_fail(buf != NULL);
/* simply set the buffer to point to the correct region of the file */
GST_BUFFER_DATA(buf) = asyncdisksrc->map + asyncdisksrc->curoffset;
GST_BUFFER_OFFSET(buf) = asyncdisksrc->curoffset;
if ((asyncdisksrc->curoffset + asyncdisksrc->bytes_per_read) >
asyncdisksrc->size) {
GST_BUFFER_SIZE(buf) = asyncdisksrc->size - asyncdisksrc->curoffset;
// FIXME: set the buffer's EOF bit here
} else
GST_BUFFER_SIZE(buf) = asyncdisksrc->bytes_per_read;
asyncdisksrc->curoffset += GST_BUFFER_SIZE(buf);
/* we're done, push the buffer off now */
gst_pad_push(asyncdisksrc->srcpad,buf);
}
/**
* gst_asyncdisksrc_push_region:
* @src: #GstSrc to push a buffer from
* @offset: offset in file
* @size: number of bytes
*
* Push a new buffer from the asyncdisksrc of given size at given offset.
*/
void gst_asyncdisksrc_push_region(GstSrc *src,gulong offset,gulong size) {
GstAsyncDiskSrc *asyncdisksrc;
GstBuffer *buf;
g_return_if_fail(src != NULL);
g_return_if_fail(GST_IS_ASYNCDISKSRC(src));
g_return_if_fail(GST_FLAG_IS_SET(src,GST_STATE_RUNNING));
asyncdisksrc = GST_ASYNCDISKSRC(src);
/* deal with EOF state */
if (offset >= asyncdisksrc->size) {
gst_src_signal_eos(GST_SRC(asyncdisksrc));
return;
}
/* create the buffer */
// FIXME: should eventually use a bufferpool for this
buf = gst_buffer_new();
g_return_if_fail(buf);
/* simply set the buffer to point to the correct region of the file */
GST_BUFFER_DATA(buf) = asyncdisksrc->map + offset;
GST_BUFFER_OFFSET(buf) = asyncdisksrc->curoffset;
if ((offset + size) > asyncdisksrc->size) {
GST_BUFFER_SIZE(buf) = asyncdisksrc->size - offset;
// FIXME: set the buffer's EOF bit here
} else
GST_BUFFER_SIZE(buf) = size;
asyncdisksrc->curoffset += GST_BUFFER_SIZE(buf);
/* we're done, push the buffer off now */
gst_pad_push(asyncdisksrc->srcpad,buf);
}
/* open the file and mmap it, necessary to go to RUNNING state */
static gboolean gst_asyncdisksrc_open_file(GstAsyncDiskSrc *src) {
g_return_if_fail(!GST_FLAG_IS_SET(src,GST_ASYNCDISKSRC_OPEN));
/* open the file */
src->fd = open(src->filename,O_RDONLY);
if (src->fd < 0) {
gst_element_error(GST_ELEMENT(src),"opening file");
return FALSE;
} else {
/* find the file length */
src->size = lseek(src->fd,0,SEEK_END);
lseek(src->fd,0,SEEK_SET);
/* map the file into memory */
src->map = mmap(NULL,src->size,PROT_READ,MAP_SHARED,src->fd,0);
/* collapse state if that failed */
if (src->map == NULL) {
close(src->fd);
gst_element_error(GST_ELEMENT(src),"mmapping file");
return FALSE;
}
GST_FLAG_SET(src,GST_ASYNCDISKSRC_OPEN);
}
return TRUE;
}
/* unmap and close the file */
static void gst_asyncdisksrc_close_file(GstAsyncDiskSrc *src) {
g_return_if_fail(GST_FLAG_IS_SET(src,GST_ASYNCDISKSRC_OPEN));
/* unmap the file from memory */
munmap(src->map,src->size);
/* close the file */
close(src->fd);
/* zero out a lot of our state */
src->fd = 0;
src->size = 0;
src->map = NULL;
src->curoffset = 0;
src->seq = 0;
GST_FLAG_UNSET(src,GST_ASYNCDISKSRC_OPEN);
}
static gboolean gst_asyncdisksrc_change_state(GstElement *element,
GstElementState state) {
g_return_if_fail(GST_IS_ASYNCDISKSRC(element));
switch (state) {
case GST_STATE_RUNNING:
if (!gst_asyncdisksrc_open_file(GST_ASYNCDISKSRC(element)))
return FALSE;
break;
case ~GST_STATE_RUNNING:
gst_asyncdisksrc_close_file(GST_ASYNCDISKSRC(element));
break;
default:
break;
}
if (GST_ELEMENT_CLASS(parent_class)->change_state)
return GST_ELEMENT_CLASS(parent_class)->change_state(element,state);
return TRUE;
}