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gst/multipart/multipartdemux.c: Uses GstAdapter instead of own buffering.

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Original commit message from CVS:
Patch by: Sjoerd Simons <sjoerd at luon dot net>
* gst/multipart/multipartdemux.c: (gst_multipart_demux_base_init),
(gst_multipart_demux_class_init), (gst_multipart_demux_init),
(gst_multipart_demux_finalize), (get_line_end),
(multipart_parse_header), (multipart_find_boundary),
(gst_multipart_demux_chain), (gst_multipart_demux_change_state),
(gst_multipart_set_property), (gst_multipart_get_property):
Uses GstAdapter instead of own buffering.
Actually parses the mime-type correctly (In tests the mime-type was
always "" with the old version).
Uses the Content-length header if available to speed up things.
Reliably autoscans the boundary name by default.
Fixes #349068.
* gst/multipart/multipartmux.c: (gst_multipart_mux_collected):
Don't start the stream with a \n.
This commit is contained in:
Sjoerd Simons 2006-07-28 16:17:17 +00:00 committed by Wim Taymans
parent da5c3416e7
commit 4441dc23ee
3 changed files with 297 additions and 208 deletions
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20
ChangeLog
View file

@ -1,3 +1,23 @@
2006-07-28 Wim Taymans <wim@fluendo.com>
Patch by: Sjoerd Simons <sjoerd at luon dot net>
* gst/multipart/multipartdemux.c: (gst_multipart_demux_base_init),
(gst_multipart_demux_class_init), (gst_multipart_demux_init),
(gst_multipart_demux_finalize), (get_line_end),
(multipart_parse_header), (multipart_find_boundary),
(gst_multipart_demux_chain), (gst_multipart_demux_change_state),
(gst_multipart_set_property), (gst_multipart_get_property):
Uses GstAdapter instead of own buffering.
Actually parses the mime-type correctly (In tests the mime-type was
always "" with the old version).
Uses the Content-length header if available to speed up things.
Reliably autoscans the boundary name by default.
Fixes #349068.
* gst/multipart/multipartmux.c: (gst_multipart_mux_collected):
Don't start the stream with a \n.
2006-07-28 Tim-Philipp Müller <tim at centricular dot net>
Patch by: Brian Cameron <brian dot cameron at sun com>

466
gst/multipart/multipartdemux.c
View file

@ -1,4 +1,5 @@
/* GStreamer
* Copyright (C) 2006 Sjoerd Simons <sjoerd@luon.net>
* Copyright (C) 2004 Wim Taymans <wim@fluendo.com>
*
* gstmultipartdemux.c: multipart stream demuxer
@ -46,8 +47,8 @@
* </para>
* <para>
* the content in multipart files is separated with a boundary string that can be
* configured specifically with the "boundary" property or can be autodetected by
* setting the "autoscan" property to TRUE.
* configured specifically with the "boundary" property otherwise it will be
* autodetected.
* </para>
* </refsect2>
*/
@ -57,6 +58,7 @@
#endif
#include <gst/gst.h>
#include <gst/base/gstadapter.h>
#include <string.h>
@ -69,7 +71,9 @@
typedef struct _GstMultipartDemux GstMultipartDemux;
typedef struct _GstMultipartDemuxClass GstMultipartDemuxClass;
#define MAX_LINE_LEN 500
#define MULTIPART_NEED_MORE_DATA -1
#define MULTIPART_DATA_ERROR -2
#define MULTIPART_DATA_EOS -3
/* all information needed for one multipart stream */
typedef struct
@ -77,11 +81,6 @@ typedef struct
GstPad *pad; /* reference for this pad is held by element we belong to */
gchar *mime;
guint64 offset; /* end offset of last buffer */
guint64 known_offset; /* last known offset */
guint flags;
}
GstMultipartPad;
@ -100,17 +99,20 @@ struct _GstMultipartDemux
GSList *srcpads;
gint numpads;
gchar *parsing_mime;
gchar *buffer;
gint maxlen;
gint bufsize;
gint scanpos;
gint lastpos;
GstAdapter *adapter;
gchar *prefix;
gint prefixLen;
gboolean first_frame;
/* Header information of the current frame */
gboolean header_completed;
gchar *boundary;
guint boundary_len;
gchar *mime_type;
gint content_length;
/* deprecated, unused */
gboolean autoscan;
/* Index inside the current data when manually looking for the boundary */
gint scanpos;
};
struct _GstMultipartDemuxClass
@ -126,7 +128,7 @@ static const GstElementDetails gst_multipart_demux_details =
GST_ELEMENT_DETAILS ("Multipart demuxer",
"Codec/Demuxer",
"demux multipart streams",
"Wim Taymans <wim@fluendo.com>");
"Wim Taymans <wim@fluendo.com>, Sjoerd Simons <sjoerd@luon.net>");
/* signals and args */
@ -136,14 +138,14 @@ enum
LAST_SIGNAL
};
#define DEFAULT_BOUNDARY "ThisRandomString"
#define DEFAULT_AUTOSCAN FALSE
#define DEFAULT_AUTOSCAN FALSE
#define DEFAULT_BOUNDARY NULL
enum
{
PROP_0,
PROP_BOUNDARY,
PROP_AUTOSCAN
/* FILL ME */
PROP_AUTOSCAN,
PROP_BOUNDARY
};
static GstStaticPadTemplate multipart_demux_src_template_factory =
@ -172,7 +174,6 @@ static void gst_multipart_get_property (GObject * object, guint prop_id,
static void gst_multipart_demux_finalize (GObject * object);
GST_BOILERPLATE (GstMultipartDemux, gst_multipart_demux, GstElement,
GST_TYPE_ELEMENT);
@ -180,37 +181,35 @@ static void
gst_multipart_demux_base_init (gpointer g_class)
{
GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);
GObjectClass *gobject_class = G_OBJECT_CLASS (g_class);
gst_element_class_set_details (element_class, &gst_multipart_demux_details);
gobject_class->set_property = gst_multipart_set_property;
gobject_class->get_property = gst_multipart_get_property;
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&multipart_demux_sink_template_factory));
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&multipart_demux_src_template_factory));
g_object_class_install_property (gobject_class, PROP_BOUNDARY,
g_param_spec_string ("boundary", "Boundary",
"The boundary string separating data", DEFAULT_BOUNDARY,
G_PARAM_READWRITE | G_PARAM_CONSTRUCT));
g_object_class_install_property (gobject_class, PROP_AUTOSCAN,
g_param_spec_boolean ("autoscan", "autoscan",
"Try to autofind the prefix", DEFAULT_AUTOSCAN,
G_PARAM_READWRITE | G_PARAM_CONSTRUCT));
gst_element_class_set_details (element_class, &gst_multipart_demux_details);
}
static void
gst_multipart_demux_class_init (GstMultipartDemuxClass * klass)
{
GstElementClass *gstelement_class = GST_ELEMENT_CLASS (klass);
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
GstElementClass *gstelement_class = GST_ELEMENT_CLASS (klass);
gobject_class->finalize = gst_multipart_demux_finalize;
gobject_class->set_property = gst_multipart_set_property;
gobject_class->get_property = gst_multipart_get_property;
g_object_class_install_property (gobject_class, PROP_BOUNDARY,
g_param_spec_string ("boundary", "Boundary",
"The boundary string separating data, automatic if NULL",
DEFAULT_BOUNDARY, G_PARAM_READWRITE | G_PARAM_CONSTRUCT));
g_object_class_install_property (gobject_class, PROP_AUTOSCAN,
g_param_spec_boolean ("autoscan", "autoscan",
"Try to autofind the prefix (deprecated unused, see boundary)",
DEFAULT_AUTOSCAN, G_PARAM_READWRITE));
gstelement_class->change_state = gst_multipart_demux_change_state;
gobject_class->finalize = gst_multipart_demux_finalize;
}
static void
@ -225,15 +224,24 @@ gst_multipart_demux_init (GstMultipartDemux * multipart,
gst_pad_set_chain_function (multipart->sinkpad,
GST_DEBUG_FUNCPTR (gst_multipart_demux_chain));
multipart->maxlen = 4096;
multipart->adapter = gst_adapter_new ();
multipart->boundary = DEFAULT_BOUNDARY;
multipart->mime_type = NULL;
multipart->content_length = -1;
multipart->header_completed = FALSE;
multipart->scanpos = 0;
multipart->autoscan = DEFAULT_AUTOSCAN;
}
static void
gst_multipart_demux_finalize (GObject * object)
{
GstMultipartDemux *demux = GST_MULTIPART_DEMUX (object);
g_free (demux->prefix);
g_object_unref (demux->adapter);
g_free (demux->boundary);
g_free (demux->mime_type);
G_OBJECT_CLASS (parent_class)->finalize (object);
}
@ -292,162 +300,226 @@ gst_multipart_find_pad_by_mime (GstMultipartDemux * demux, gchar * mime,
}
}
static gboolean
get_line_end (const guint8 * data, const guint8 * dataend, guint8 ** end,
guint8 ** next)
{
guint8 *x;
gboolean foundr = FALSE;
for (x = (guint8 *) data; x < dataend; x++) {
if (*x == '\r') {
foundr = TRUE;
} else if (*x == '\n') {
*end = x - (foundr ? 1 : 0);
*next = x + 1;
return TRUE;
}
}
return FALSE;
}
static gint
multipart_parse_header (GstMultipartDemux * multipart)
{
const guint8 *data;
const guint8 *dataend;
gchar *boundary;
int boundary_len;
int datalen;
guint8 *pos;
guint8 *end, *next;
datalen = gst_adapter_available (multipart->adapter);
data = gst_adapter_peek (multipart->adapter, datalen);
dataend = data + datalen;
/* First the boundary */
if (!get_line_end (data, dataend, &end, &next))
return MULTIPART_NEED_MORE_DATA;
/* Ignore the leading -- */
boundary_len = end - data - 2;
boundary = (gchar *) data + 2;
if (boundary_len < 1) {
GST_DEBUG_OBJECT (multipart, "No boundary available");
goto wrong_header;
}
if (G_UNLIKELY (multipart->boundary == NULL)) {
/* First time we see the boundary, copy it */
multipart->boundary = g_strndup (boundary, boundary_len);
multipart->boundary_len = boundary_len;
} else if (G_UNLIKELY (boundary_len != multipart->boundary_len)) {
/* Something odd is going on, either the boundary indicated EOS or it's
* invalid */
if (G_UNLIKELY (boundary_len == multipart->boundary_len + 2 &&
!strncmp (boundary, multipart->boundary, multipart->boundary_len) &&
!strncmp (boundary + multipart->boundary_len, "--", 2))) {
return MULTIPART_DATA_EOS;
}
GST_DEBUG_OBJECT (multipart,
"Boundary length doesn't match detected boundary (%d <> %d",
boundary_len, multipart->boundary_len);
goto wrong_header;
} else if (G_UNLIKELY (strncmp (boundary, multipart->boundary, boundary_len))) {
GST_DEBUG_OBJECT (multipart, "Boundary doesn't match previous boundary");
goto wrong_header;
}
pos = next;
while (get_line_end (pos, dataend, &end, &next)) {
guint len = end - pos;
if (len == 0) {
/* empty line, data starts behind us */
GST_DEBUG_OBJECT (multipart,
"Parsed the header - boundary: %s, mime-type: %s, content-length: %d",
multipart->boundary, multipart->mime_type, multipart->content_length);
return next - data;
}
if (len >= 14 && !g_ascii_strncasecmp ("content-type:", (gchar *) pos, 13)) {
g_free (multipart->mime_type);
multipart->mime_type = g_strndup ((gchar *) pos + 14, len - 14);
} else if (len >= 15 &&
!g_ascii_strncasecmp ("content-length:", (gchar *) pos, 15)) {
multipart->content_length =
g_ascii_strtoull ((gchar *) pos + 15, NULL, 10);
}
pos = next;
}
GST_DEBUG_OBJECT (multipart, "Need more data for the header");
return MULTIPART_NEED_MORE_DATA;
wrong_header:
{
GST_ELEMENT_ERROR (multipart, STREAM, DEMUX, (NULL),
("Boundary not found in the multipart header"));
return MULTIPART_DATA_ERROR;
}
}
static gint
multipart_find_boundary (GstMultipartDemux * multipart, gint * datalen)
{
/* Adaptor is positioned at the start of the data */
const guint8 *data, *pos;
const guint8 *dataend;
gint len;
if (multipart->content_length >= 0) {
/* fast path, known content length :) */
len = multipart->content_length;
if (gst_adapter_available (multipart->adapter) >= len + 2) {
*datalen = len;
data = gst_adapter_peek (multipart->adapter, len + 1);
/* If data[len] contains \r then assume a newline is \r\n */
if (data[len] == '\r')
len += 2;
else if (data[len] == '\n')
len += 1;
/* Don't check if boundary is actually there, but let the header parsing
* bail out if it isn't */
return len;
} else {
/* need more data */
return MULTIPART_NEED_MORE_DATA;
}
}
len = gst_adapter_available (multipart->adapter);
if (len == 0)
return MULTIPART_NEED_MORE_DATA;
data = gst_adapter_peek (multipart->adapter, len);
dataend = data + len;
for (pos = data + multipart->scanpos;
pos <= dataend - multipart->boundary_len - 2; pos++) {
if (*pos == '-' && pos[1] == '-' &&
!strncmp ((gchar *) pos + 2,
multipart->boundary, multipart->boundary_len)) {
/* Found the boundary! Check if there was a newline before the boundary */
len = pos - data;
if (pos - 2 > data && pos[-2] == '\r')
len -= 2;
else if (pos - 1 > data && pos[-1] == '\n')
len -= 1;
*datalen = len;
multipart->scanpos = 0;
return pos - data;
}
}
multipart->scanpos = pos - data;
return MULTIPART_NEED_MORE_DATA;
}
static GstFlowReturn
gst_multipart_demux_chain (GstPad * pad, GstBuffer * buf)
{
GstMultipartDemux *multipart;
gint size, matchpos;
guchar *data;
GstFlowReturn ret = GST_FLOW_OK;
GstAdapter *adapter;
gint size = 1;
multipart = GST_MULTIPART_DEMUX (gst_pad_get_parent (pad));
adapter = multipart->adapter;
data = GST_BUFFER_DATA (buf);
size = GST_BUFFER_SIZE (buf);
/* first make sure our buffer is long enough */
if (multipart->bufsize + size > multipart->maxlen) {
gint newsize = (multipart->bufsize + size) * 2;
multipart->buffer = g_realloc (multipart->buffer, newsize);
multipart->maxlen = newsize;
if (GST_BUFFER_FLAG_IS_SET (buf, GST_BUFFER_FLAG_DISCONT)) {
gst_adapter_clear (adapter);
}
/* copy bytes into the buffer */
memcpy (multipart->buffer + multipart->bufsize, data, size);
multipart->bufsize += size;
gst_adapter_push (adapter, buf);
if (multipart->first_frame && multipart->autoscan) {
/* find the prefix if this is the first buffer */
/* the prefix is like --prefix\r\n */
size_t i, start;
while (gst_adapter_available (adapter) > 0) {
GstMultipartPad *srcpad;
GstBuffer *outbuf;
gboolean created;
gint datalen;
i = 0;
start = -1;
while ((i + 1) < multipart->bufsize) {
if (-1 == start) {
if ((multipart->buffer[i] == '-') && (multipart->buffer[i + 1] == '-')) {
start = i + 2; /* discart -- */
}
if (G_UNLIKELY (!multipart->header_completed)) {
if ((size = multipart_parse_header (multipart)) < 0) {
goto nodata;
} else {
/* look for \r\n or \n\n */
if ((multipart->buffer[i] == '\n') ||
((multipart->buffer[i] == '\r') &&
(multipart->buffer[i + 1] == '\n'))) {
/* found first \r\n, the prefix is from 0 to i */
g_free (multipart->prefix);
multipart->prefix =
g_strndup (multipart->buffer + start, (i - start));
multipart->prefixLen = strlen (multipart->prefix);
GST_DEBUG_OBJECT (multipart,
"set prefix to [%s]\n", multipart->prefix);
multipart->first_frame = FALSE;
break;
}
gst_adapter_flush (adapter, size);
multipart->header_completed = TRUE;
}
i++;
}
}
/* find \n */
while (multipart->scanpos < multipart->bufsize) {
if (multipart->buffer[multipart->scanpos] == '\n') {
break;
if ((size = multipart_find_boundary (multipart, &datalen)) < 0) {
goto nodata;
}
multipart->scanpos++;
}
srcpad =
gst_multipart_find_pad_by_mime (multipart,
multipart->mime_type, &created);
outbuf = gst_adapter_take_buffer (adapter, datalen);
gst_adapter_flush (adapter, size - datalen);
/* then scan for the boundary */
for (matchpos = 0;
multipart->scanpos + multipart->prefixLen + MAX_LINE_LEN - matchpos <
multipart->bufsize; multipart->scanpos++) {
if (multipart->buffer[multipart->scanpos] == multipart->prefix[matchpos]) {
/* Invalidate header info */
multipart->header_completed = FALSE;
multipart->content_length = -1;
matchpos++;
if (matchpos == multipart->prefixLen) {
int datalen;
int i, start;
gchar *mime_type;
gst_buffer_set_caps (outbuf, GST_PAD_CAPS (srcpad->pad));
if (created) {
GstEvent *event;
multipart->scanpos++;
start = multipart->scanpos;
/* find \n */
for (i = 0; i < MAX_LINE_LEN; i++) {
if (multipart->buffer[multipart->scanpos] == '\n')
break;
multipart->scanpos++;
matchpos++;
}
mime_type =
g_strndup (multipart->buffer + start, multipart->scanpos - start);
multipart->scanpos += 2;
matchpos += 3;
datalen = multipart->scanpos - matchpos;
if (datalen > 0 && multipart->parsing_mime) {
GstBuffer *outbuf;
GstMultipartPad *srcpad;
gboolean created = FALSE;
srcpad =
gst_multipart_find_pad_by_mime (multipart,
multipart->parsing_mime, &created);
if (srcpad != NULL) {
ret =
gst_pad_alloc_buffer_and_set_caps (srcpad->pad,
GST_BUFFER_OFFSET_NONE, datalen, GST_PAD_CAPS (srcpad->pad),
&outbuf);
if (ret != GST_FLOW_OK) {
GST_WARNING_OBJECT (multipart, "failed allocating a %d bytes "
"buffer", datalen);
} else {
memcpy (GST_BUFFER_DATA (outbuf), multipart->buffer, datalen);
if (created) {
GstEvent *event;
/* Push new segment */
event = gst_event_new_new_segment (FALSE, 1.0, GST_FORMAT_TIME,
0, -1, 0);
if (GST_IS_EVENT (event)) {
gst_pad_push_event (srcpad->pad, event);
}
GST_BUFFER_TIMESTAMP (outbuf) = 0;
} else {
GST_BUFFER_TIMESTAMP (outbuf) = -1;
}
ret = gst_pad_push (srcpad->pad, outbuf);
}
}
}
/* move rest downward */
multipart->bufsize -= multipart->scanpos;
memmove (multipart->buffer, multipart->buffer + multipart->scanpos,
multipart->bufsize);
g_free (multipart->parsing_mime);
multipart->parsing_mime = mime_type;
multipart->scanpos = 0;
}
/* Push new segment, first buffer has 0 timestamp */
event = gst_event_new_new_segment (FALSE, 1.0, GST_FORMAT_TIME, 0, -1, 0);
gst_pad_push_event (srcpad->pad, event);
GST_BUFFER_TIMESTAMP (outbuf) = 0;
} else {
matchpos = 0;
GST_BUFFER_TIMESTAMP (outbuf) = -1;
}
if (ret != GST_FLOW_OK)
break;
gst_pad_push (srcpad->pad, outbuf);
}
gst_buffer_unref (buf);
nodata:
gst_object_unref (multipart);
return ret;
if (G_UNLIKELY (size == MULTIPART_DATA_ERROR))
return GST_FLOW_ERROR;
if (G_UNLIKELY (size == MULTIPART_DATA_EOS))
return GST_FLOW_UNEXPECTED;
return GST_FLOW_OK;
}
static GstStateChangeReturn
@ -459,23 +531,6 @@ gst_multipart_demux_change_state (GstElement * element,
multipart = GST_MULTIPART_DEMUX (element);
switch (transition) {
case GST_STATE_CHANGE_NULL_TO_READY:
break;
case GST_STATE_CHANGE_READY_TO_PAUSED:
multipart->buffer = g_malloc (multipart->maxlen);
multipart->first_frame = TRUE;
multipart->parsing_mime = NULL;
multipart->numpads = 0;
multipart->scanpos = 0;
multipart->lastpos = 0;
break;
case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
break;
default:
break;
}
ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
if (ret == GST_STATE_CHANGE_FAILURE)
return ret;
@ -484,10 +539,12 @@ gst_multipart_demux_change_state (GstElement * element,
case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
break;
case GST_STATE_CHANGE_PAUSED_TO_READY:
g_free (multipart->parsing_mime);
multipart->parsing_mime = NULL;
g_free (multipart->buffer);
multipart->buffer = NULL;
multipart->header_completed = FALSE;
g_free (multipart->boundary);
multipart->boundary = NULL;
g_free (multipart->mime_type);
multipart->mime_type = NULL;
gst_adapter_clear (multipart->adapter);
break;
case GST_STATE_CHANGE_READY_TO_NULL:
break;
@ -509,9 +566,12 @@ gst_multipart_set_property (GObject * object, guint prop_id,
switch (prop_id) {
case PROP_BOUNDARY:
g_free (filter->prefix);
filter->prefix = g_value_dup_string (value);
filter->prefixLen = strlen (filter->prefix);
/* Not really that usefull anymore as we can reliably autoscan */
g_free (filter->boundary);
filter->boundary = g_value_dup_string (value);
if (filter->boundary != NULL) {
filter->boundary_len = strlen (filter->boundary);
}
break;
case PROP_AUTOSCAN:
filter->autoscan = g_value_get_boolean (value);
@ -533,7 +593,7 @@ gst_multipart_get_property (GObject * object, guint prop_id,
switch (prop_id) {
case PROP_BOUNDARY:
g_value_set_string (value, filter->prefix);
g_value_set_string (value, filter->boundary);
break;
case PROP_AUTOSCAN:
g_value_set_boolean (value, filter->autoscan);

19
gst/multipart/multipartmux.c
View file

@ -445,6 +445,8 @@ gst_multipart_mux_collected (GstCollectPads * pads, GstMultipartMux * mux)
size_t newlen, headerlen;
GstBuffer *newbuf = NULL;
GstStructure *structure = NULL;
guint8 *data;
guint datasize;
GST_DEBUG_OBJECT (mux, "all pads are collected");
@ -483,11 +485,14 @@ gst_multipart_mux_collected (GstCollectPads * pads, GstMultipartMux * mux)
goto beach;
}
header = g_strdup_printf ("\n--%s\nContent-type: %s\n\n",
header = g_strdup_printf ("--%s\nContent-type: %s\n\n",
mux->boundary, gst_structure_get_name (structure));
datasize = GST_BUFFER_SIZE (best->buffer);
headerlen = strlen (header);
newlen = headerlen + GST_BUFFER_SIZE (best->buffer);
/* header, data, trailing \n */
newlen = headerlen + datasize + 1;
ret =
gst_pad_alloc_buffer_and_set_caps (mux->srcpad, GST_BUFFER_OFFSET_NONE,
@ -498,9 +503,13 @@ gst_multipart_mux_collected (GstCollectPads * pads, GstMultipartMux * mux)
goto beach;
}
memcpy (GST_BUFFER_DATA (newbuf), header, headerlen);
memcpy (GST_BUFFER_DATA (newbuf) + headerlen,
GST_BUFFER_DATA (best->buffer), GST_BUFFER_SIZE (best->buffer));
data = GST_BUFFER_DATA (newbuf);
memcpy (data, header, headerlen);
memcpy (data + headerlen, GST_BUFFER_DATA (best->buffer), datasize);
/* trailing \n */
data[headerlen + datasize] = '\n';
gst_buffer_stamp (newbuf, best->buffer);
GST_BUFFER_OFFSET (newbuf) = mux->offset;