gstreamer/gst/gstpluginloader.c

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/* GStreamer
* Copyright (C) 2008 Jan Schmidt <jan.schmidt@sun.com>
*
* gstpluginloader.c: GstPluginLoader helper for loading plugin files
* out of process.
*
* 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.
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <gst/gst_private.h>
#ifndef G_OS_WIN32
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#else
#define fsync(fd) _commit(fd)
#include <io.h>
#endif
#include <errno.h>
#include <gst/gstconfig.h>
#include <gst/gstpoll.h>
#include <gst/gstutils.h>
#include <gst/gstpluginloader.h>
#include <gst/gstregistrychunks.h>
#include <gst/gstregistrybinary.h>
/* IMPORTANT: Bump the version number if the plugin loader packet protocol
* changes. Changes in the binary registry format itself are handled by
* bumping the GST_MAGIC_BINARY_VERSION_STR
*/
static const guint32 loader_protocol_version = 3;
#define GST_CAT_DEFAULT GST_CAT_PLUGIN_LOADING
static GstPluginLoader *plugin_loader_new (GstRegistry * registry);
static gboolean plugin_loader_free (GstPluginLoader * loader);
static gboolean plugin_loader_load (GstPluginLoader * loader,
const gchar * filename, off_t file_size, time_t file_mtime);
const GstPluginLoaderFuncs _priv_gst_plugin_loader_funcs = {
plugin_loader_new, plugin_loader_free, plugin_loader_load
};
typedef struct _PendingPluginEntry
{
guint32 tag;
gchar *filename;
off_t file_size;
time_t file_mtime;
} PendingPluginEntry;
struct _GstPluginLoader
{
GstRegistry *registry;
GstPoll *fdset;
gboolean child_running;
GPid child_pid;
GstPollFD fd_w;
GstPollFD fd_r;
gboolean is_child;
gboolean got_plugin_details;
/* Transmit buffer */
guint8 *tx_buf;
guint tx_buf_size;
guint tx_buf_write;
guint tx_buf_read;
guint32 next_tag;
guint8 *rx_buf;
guint rx_buf_size;
gboolean rx_done;
gboolean rx_got_sync;
/* Head and tail of the pending plugins list. List of
PendingPluginEntry structs */
GList *pending_plugins;
GList *pending_plugins_tail;
};
#define PACKET_EXIT 1
#define PACKET_LOAD_PLUGIN 2
#define PACKET_SYNC 3
#define PACKET_PLUGIN_DETAILS 4
#define PACKET_VERSION 5
#define BUF_INIT_SIZE 512
#define BUF_GROW_EXTRA 512
#define BUF_MAX_SIZE (32 * 1024 * 1024)
#define HEADER_SIZE 12
/* 4 magic hex bytes to mark each packet */
#define HEADER_MAGIC 0xbefec0ae
#define ALIGNMENT (sizeof (void *))
static gboolean gst_plugin_loader_spawn (GstPluginLoader * loader);
static void put_packet (GstPluginLoader * loader, guint type, guint32 tag,
const guint8 * payload, guint32 payload_len);
static gboolean exchange_packets (GstPluginLoader * l);
static gboolean plugin_loader_replay_pending (GstPluginLoader * l);
static gboolean plugin_loader_load_and_sync (GstPluginLoader * l,
PendingPluginEntry * entry);
static void plugin_loader_create_blacklist_plugin (GstPluginLoader * l,
PendingPluginEntry * entry);
static void plugin_loader_cleanup_child (GstPluginLoader * loader);
static gboolean plugin_loader_sync_with_child (GstPluginLoader * l);
static GstPluginLoader *
plugin_loader_new (GstRegistry * registry)
{
GstPluginLoader *l = g_new0 (GstPluginLoader, 1);
if (registry)
l->registry = gst_object_ref (registry);
l->fdset = gst_poll_new (FALSE);
gst_poll_fd_init (&l->fd_w);
gst_poll_fd_init (&l->fd_r);
l->tx_buf_size = BUF_INIT_SIZE;
l->tx_buf = g_malloc (BUF_INIT_SIZE);
l->next_tag = 0;
l->rx_buf_size = BUF_INIT_SIZE;
l->rx_buf = g_malloc (BUF_INIT_SIZE);
return l;
}
static gboolean
plugin_loader_free (GstPluginLoader * loader)
{
GList *cur;
gboolean got_plugin_details;
fsync (loader->fd_w.fd);
if (loader->child_running) {
put_packet (loader, PACKET_EXIT, 0, NULL, 0);
/* Swap packets with the child until it exits cleanly */
while (!loader->rx_done) {
if (exchange_packets (loader) || loader->rx_done)
continue;
if (!plugin_loader_replay_pending (loader))
break;
put_packet (loader, PACKET_EXIT, 0, NULL, 0);
}
plugin_loader_cleanup_child (loader);
} else {
close (loader->fd_w.fd);
close (loader->fd_r.fd);
}
gst_poll_free (loader->fdset);
g_free (loader->rx_buf);
g_free (loader->tx_buf);
if (loader->registry)
gst_object_unref (loader->registry);
got_plugin_details = loader->got_plugin_details;
/* Free any pending plugin entries */
cur = loader->pending_plugins;
while (cur) {
PendingPluginEntry *entry = (PendingPluginEntry *) (cur->data);
g_free (entry->filename);
g_free (entry);
cur = g_list_delete_link (cur, cur);
}
g_free (loader);
return got_plugin_details;
}
static gboolean
plugin_loader_load (GstPluginLoader * loader, const gchar * filename,
off_t file_size, time_t file_mtime)
{
gint len;
PendingPluginEntry *entry;
if (!gst_plugin_loader_spawn (loader))
return FALSE;
/* Send a packet to the child requesting that it load the given file */
GST_LOG_OBJECT (loader->registry,
"Sending file %s to child. tag %u", filename, loader->next_tag);
entry = g_new (PendingPluginEntry, 1);
entry->tag = loader->next_tag++;
entry->filename = g_strdup (filename);
entry->file_size = file_size;
entry->file_mtime = file_mtime;
loader->pending_plugins_tail =
g_list_append (loader->pending_plugins_tail, entry);
if (loader->pending_plugins == NULL)
loader->pending_plugins = loader->pending_plugins_tail;
else
loader->pending_plugins_tail = g_list_next (loader->pending_plugins_tail);
len = strlen (filename);
put_packet (loader, PACKET_LOAD_PLUGIN, entry->tag,
(guint8 *) filename, len + 1);
if (!exchange_packets (loader)) {
if (!plugin_loader_replay_pending (loader))
return FALSE;
}
return TRUE;
}
static gboolean
plugin_loader_replay_pending (GstPluginLoader * l)
{
GList *cur, *next;
restart:
if (!gst_plugin_loader_spawn (l))
return FALSE;
/* Load each plugin one by one synchronously until we find the
* crashing one */
while ((cur = l->pending_plugins)) {
PendingPluginEntry *entry = (PendingPluginEntry *) (cur->data);
if (!plugin_loader_load_and_sync (l, entry)) {
/* Create dummy plugin entry to block re-scanning this file */
GST_ERROR ("Plugin file %s failed to load. Blacklisting",
entry->filename);
plugin_loader_create_blacklist_plugin (l, entry);
l->got_plugin_details = TRUE;
/* Now remove this crashy plugin from the head of the list */
l->pending_plugins = g_list_delete_link (cur, cur);
if (l->pending_plugins == NULL)
l->pending_plugins_tail = NULL;
if (!gst_plugin_loader_spawn (l))
return FALSE;
break;
}
}
/* We exited after finding the crashing one. If there's any more pending,
* dispatch them post-haste, but don't wait */
for (cur = l->pending_plugins; cur != NULL; cur = next) {
PendingPluginEntry *entry = (PendingPluginEntry *) (cur->data);
next = g_list_next (cur);
put_packet (l, PACKET_LOAD_PLUGIN, entry->tag,
(guint8 *) entry->filename, strlen (entry->filename) + 1);
/* This might invalidate cur, which is why we grabbed 'next' above */
if (!exchange_packets (l))
goto restart;
}
return TRUE;
}
static gboolean
plugin_loader_sync_with_child (GstPluginLoader * l)
{
put_packet (l, PACKET_SYNC, 0, NULL, 0);
l->rx_got_sync = FALSE;
while (!l->rx_got_sync) {
if (!exchange_packets (l))
return FALSE;
}
return TRUE;
}
static gboolean
plugin_loader_load_and_sync (GstPluginLoader * l, PendingPluginEntry * entry)
{
gint len;
GST_DEBUG_OBJECT (l->registry, "Synchronously loading plugin file %s",
entry->filename);
len = strlen (entry->filename);
put_packet (l, PACKET_LOAD_PLUGIN, entry->tag,
(guint8 *) entry->filename, len + 1);
return plugin_loader_sync_with_child (l);
}
static void
plugin_loader_create_blacklist_plugin (GstPluginLoader * l,
PendingPluginEntry * entry)
{
GstPlugin *plugin = g_object_newv (GST_TYPE_PLUGIN, 0, NULL);
plugin->filename = g_strdup (entry->filename);
plugin->file_mtime = entry->file_mtime;
plugin->file_size = entry->file_size;
plugin->flags |= GST_PLUGIN_FLAG_BLACKLISTED;
plugin->basename = g_path_get_basename (plugin->filename);
plugin->desc.name = g_intern_string (plugin->basename);
plugin->desc.description = g_strdup_printf ("Plugin for blacklisted file");
plugin->desc.version = g_intern_string ("0.0.0");
plugin->desc.license = g_intern_string ("BLACKLIST");
plugin->desc.source = plugin->desc.license;
plugin->desc.package = plugin->desc.license;
plugin->desc.origin = plugin->desc.license;
GST_DEBUG ("Adding blacklist plugin '%s'", plugin->desc.name);
gst_registry_add_plugin (l->registry, plugin);
}
static gboolean
gst_plugin_loader_try_helper (GstPluginLoader * loader, gchar * location)
{
char *argv[] = { location, "-l", NULL };
GST_LOG ("Trying to spawn gst-plugin-scanner helper at %s", location);
if (!g_spawn_async_with_pipes (NULL, argv, NULL,
G_SPAWN_DO_NOT_REAP_CHILD /* | G_SPAWN_STDERR_TO_DEV_NULL */ ,
NULL, NULL, &loader->child_pid, &loader->fd_w.fd, &loader->fd_r.fd,
NULL, NULL))
return FALSE;
gst_poll_add_fd (loader->fdset, &loader->fd_w);
gst_poll_add_fd (loader->fdset, &loader->fd_r);
gst_poll_fd_ctl_read (loader->fdset, &loader->fd_r, TRUE);
loader->tx_buf_write = loader->tx_buf_read = 0;
put_packet (loader, PACKET_VERSION, 0, NULL, 0);
if (!plugin_loader_sync_with_child (loader))
return FALSE;
loader->child_running = TRUE;
return TRUE;
}
static gboolean
gst_plugin_loader_spawn (GstPluginLoader * loader)
{
const gchar *env;
char *helper_bin;
gboolean res = FALSE;
if (loader->child_running)
return TRUE;
/* Find the gst-plugin-scanner: first try the env-var if it is set,
* otherwise use the installed version */
env = g_getenv ("GST_PLUGIN_SCANNER");
if (env != NULL && *env != '\0') {
GST_LOG ("Trying GST_PLUGIN_SCANNER env var: %s", env);
helper_bin = g_strdup (env);
res = gst_plugin_loader_try_helper (loader, helper_bin);
g_free (helper_bin);
}
if (!res) {
GST_LOG ("Trying installed plugin scanner");
helper_bin = g_strdup (GST_PLUGIN_SCANNER_INSTALLED);
res = gst_plugin_loader_try_helper (loader, helper_bin);
g_free (helper_bin);
if (!res) {
GST_INFO ("No gst-plugin-scanner available, or not working");
}
}
return loader->child_running;
}
static void
plugin_loader_cleanup_child (GstPluginLoader * l)
{
if (!l->child_running || l->is_child)
return;
gst_poll_remove_fd (l->fdset, &l->fd_w);
gst_poll_remove_fd (l->fdset, &l->fd_r);
close (l->fd_w.fd);
close (l->fd_r.fd);
#ifndef G_OS_WIN32
GST_LOG ("waiting for child process to exit");
waitpid (l->child_pid, NULL, 0);
#else
g_warning ("FIXME: Implement child process shutdown for Win32");
#endif
g_spawn_close_pid (l->child_pid);
l->child_running = FALSE;
}
gboolean
_gst_plugin_loader_client_run ()
{
GstPluginLoader *l;
l = plugin_loader_new (NULL);
if (l == NULL)
return FALSE;
/* On entry, the inward pipe is STDIN, and outward is STDOUT.
* Dup those somewhere better so that plugins printing things
* won't interfere with anything */
#ifndef G_OS_WIN32
{
int dup_fd;
dup_fd = dup (0); /* STDIN */
if (dup_fd == -1) {
GST_ERROR ("Failed to start. Could no dup STDIN, errno %d", errno);
return FALSE;
}
l->fd_r.fd = dup_fd;
close (0);
dup_fd = dup (1); /* STDOUT */
if (dup_fd == -1) {
GST_ERROR ("Failed to start. Could no dup STDOUT, errno %d", errno);
return FALSE;
}
l->fd_w.fd = dup_fd;
close (1);
/* Dup stderr down to stdout so things that plugins print are visible,
* but don't care if it fails */
dup2 (2, 1);
}
#else
/* FIXME: Use DuplicateHandle and friends on win32 */
l->fd_w.fd = 1; /* STDOUT */
l->fd_r.fd = 0; /* STDIN */
#endif
gst_poll_add_fd (l->fdset, &l->fd_w);
gst_poll_add_fd (l->fdset, &l->fd_r);
gst_poll_fd_ctl_read (l->fdset, &l->fd_r, TRUE);
l->is_child = TRUE;
GST_DEBUG ("Plugin scanner child running. Waiting for instructions");
/* Loop, listening for incoming packets on the fd and writing responses */
while (!l->rx_done && exchange_packets (l));
plugin_loader_free (l);
return TRUE;
}
static void
put_packet (GstPluginLoader * l, guint type, guint32 tag,
const guint8 * payload, guint32 payload_len)
{
guint8 *out;
guint len = payload_len + HEADER_SIZE;
if (l->tx_buf_write + len >= l->tx_buf_size) {
GST_LOG ("Expanding tx buf from %d to %d for packet of size %d",
l->tx_buf_size, l->tx_buf_write + len + BUF_GROW_EXTRA, len);
l->tx_buf_size = l->tx_buf_write + len + BUF_GROW_EXTRA;
l->tx_buf = g_realloc (l->tx_buf, l->tx_buf_size);
}
out = l->tx_buf + l->tx_buf_write;
/* one byte packet type */
out[0] = type;
/* 3 byte packet tag number */
GST_WRITE_UINT24_BE (out + 1, tag);
/* 4 bytes packet length */
GST_WRITE_UINT32_BE (out + 4, payload_len);
/* payload */
memcpy (out + HEADER_SIZE, payload, payload_len);
/* Write magic into the header */
GST_WRITE_UINT32_BE (out + 8, HEADER_MAGIC);
l->tx_buf_write += len;
gst_poll_fd_ctl_write (l->fdset, &l->fd_w, TRUE);
}
static void
put_chunk (GstPluginLoader * l, GstRegistryChunk * chunk, guint * pos)
{
guint padsize = 0;
guint len;
guint8 *out;
/* Might need to align the chunk */
if (chunk->align && ((*pos) % ALIGNMENT) != 0)
padsize = ALIGNMENT - ((*pos) % ALIGNMENT);
len = padsize + chunk->size;
if (G_UNLIKELY (l->tx_buf_write + len >= l->tx_buf_size)) {
guint new_size = MAX (l->tx_buf_write + len,
l->tx_buf_size + l->tx_buf_size / 4) + BUF_GROW_EXTRA;
GST_LOG ("Expanding tx buf from %d to %d for chunk of size %d",
l->tx_buf_size, new_size, chunk->size);
l->tx_buf_size = new_size;
l->tx_buf = g_realloc (l->tx_buf, l->tx_buf_size);
}
out = l->tx_buf + l->tx_buf_write;
/* Clear the padding */
if (padsize)
memset (out, 0, padsize);
memcpy (out + padsize, chunk->data, chunk->size);
l->tx_buf_write += len;
*pos += len;
gst_poll_fd_ctl_write (l->fdset, &l->fd_w, TRUE);
};
static gboolean
write_one (GstPluginLoader * l)
{
guint8 *out;
guint32 to_write, magic;
int res;
if (l->tx_buf_read + HEADER_SIZE > l->tx_buf_write)
return FALSE;
out = l->tx_buf + l->tx_buf_read;
magic = GST_READ_UINT32_BE (out + 8);
if (magic != HEADER_MAGIC) {
GST_ERROR ("Packet magic number is missing. Memory corruption detected");
goto fail_and_cleanup;
}
to_write = GST_READ_UINT32_BE (out + 4) + HEADER_SIZE;
/* Check that the magic is intact, and the size is sensible */
if (to_write > l->tx_buf_size) {
GST_ERROR ("Indicated packet size is too large. Corruption detected");
goto fail_and_cleanup;
}
l->tx_buf_read += to_write;
GST_LOG ("Writing packet of size %d bytes to fd %d", to_write, l->fd_w.fd);
do {
res = write (l->fd_w.fd, out, to_write);
if (G_UNLIKELY (res < 0)) {
if (errno == EAGAIN || errno == EINTR)
continue;
/* Failed to write -> child died */
goto fail_and_cleanup;
}
to_write -= res;
out += res;
} while (to_write > 0);
if (l->tx_buf_read == l->tx_buf_write) {
gst_poll_fd_ctl_write (l->fdset, &l->fd_w, FALSE);
l->tx_buf_read = l->tx_buf_write = 0;
}
return TRUE;
fail_and_cleanup:
plugin_loader_cleanup_child (l);
return FALSE;
}
static gboolean
do_plugin_load (GstPluginLoader * l, const gchar * filename, guint tag)
{
GstPlugin *newplugin;
GList *chunks = NULL;
GST_DEBUG ("Plugin scanner loading file %s. tag %u\n", filename, tag);
#if 0 /* Test code - crash based on filename */
if (strstr (filename, "coreelements") == NULL) {
g_printerr ("Crashing on file %s\n", filename);
g_printerr ("%d", *(gint *) (NULL));
}
#endif
newplugin = gst_plugin_load_file ((gchar *) filename, NULL);
if (newplugin) {
guint hdr_pos;
guint offset;
/* Now serialise the plugin details and send */
if (!_priv_gst_registry_chunks_save_plugin (&chunks,
gst_registry_get_default (), newplugin))
goto fail;
/* Store where the header is, write an empty one, then write
* all the payload chunks, then fix up the header size */
hdr_pos = l->tx_buf_write;
offset = HEADER_SIZE;
put_packet (l, PACKET_PLUGIN_DETAILS, tag, NULL, 0);
if (chunks) {
GList *walk;
for (walk = chunks; walk; walk = g_list_next (walk)) {
GstRegistryChunk *cur = walk->data;
put_chunk (l, cur, &offset);
if (!(cur->flags & GST_REGISTRY_CHUNK_FLAG_CONST))
g_free (cur->data);
g_free (cur);
}
g_list_free (chunks);
/* Store the size of the written payload */
GST_WRITE_UINT32_BE (l->tx_buf + hdr_pos + 4, offset - HEADER_SIZE);
}
#if 0 /* Test code - corrupt the tx buffer based on filename */
if (strstr (filename, "sink") != NULL) {
int fd, res;
g_printerr ("Corrupting tx buf on file %s\n", filename);
fd = open ("/dev/urandom", O_RDONLY);
res = read (fd, l->tx_buf, l->tx_buf_size);
close (fd);
}
#endif
gst_object_unref (newplugin);
} else {
put_packet (l, PACKET_PLUGIN_DETAILS, tag, NULL, 0);
}
return TRUE;
fail:
put_packet (l, PACKET_PLUGIN_DETAILS, tag, NULL, 0);
if (chunks) {
GList *walk;
for (walk = chunks; walk; walk = g_list_next (walk)) {
GstRegistryChunk *cur = walk->data;
if (!(cur->flags & GST_REGISTRY_CHUNK_FLAG_CONST))
g_free (cur->data);
g_free (cur);
}
g_list_free (chunks);
}
return FALSE;
}
static gboolean
check_protocol_version (GstPluginLoader * l, guint8 * payload,
guint payload_len)
{
guint32 got_version;
guint8 *binary_reg_ver;
if (payload_len < sizeof (guint32) + GST_MAGIC_BINARY_VERSION_LEN)
return FALSE;
got_version = GST_READ_UINT32_BE (payload);
GST_LOG ("Got VERSION %u from child. Ours is %u", got_version,
loader_protocol_version);
if (got_version != loader_protocol_version)
return FALSE;
binary_reg_ver = payload + sizeof (guint32);
if (strcmp ((gchar *) binary_reg_ver, GST_MAGIC_BINARY_VERSION_STR)) {
GST_LOG ("Binary chunk format of child is different. Ours: %s, child %s\n",
GST_MAGIC_BINARY_VERSION_STR, binary_reg_ver);
return FALSE;
}
return TRUE;
};
static gboolean
handle_rx_packet (GstPluginLoader * l,
guint pack_type, guint32 tag, guint8 * payload, guint payload_len)
{
gboolean res = TRUE;
switch (pack_type) {
case PACKET_EXIT:
gst_poll_fd_ctl_read (l->fdset, &l->fd_r, FALSE);
if (l->is_child) {
/* Respond, then we keep looping until the parent closes the fd */
put_packet (l, PACKET_EXIT, 0, NULL, 0);
} else {
l->rx_done = TRUE; /* All done reading from child */
}
return TRUE;
case PACKET_LOAD_PLUGIN:{
if (!l->is_child)
return TRUE;
/* Payload is the filename to load */
res = do_plugin_load (l, (gchar *) payload, tag);
break;
}
case PACKET_PLUGIN_DETAILS:{
gchar *tmp = (gchar *) payload;
PendingPluginEntry *entry = NULL;
GList *cur;
GST_DEBUG_OBJECT (l->registry,
"Received plugin details from child w/ tag %u. %d bytes info",
tag, payload_len);
/* Assume that tagged details come back in the order
* we requested, and delete anything before (but not
* including) this one */
cur = l->pending_plugins;
while (cur) {
PendingPluginEntry *e = (PendingPluginEntry *) (cur->data);
if (e->tag > tag)
break;
if (e->tag == tag) {
entry = e;
break;
} else {
cur = g_list_delete_link (cur, cur);
g_free (e->filename);
g_free (e);
}
}
l->pending_plugins = cur;
if (cur == NULL)
l->pending_plugins_tail = NULL;
if (payload_len > 0) {
GstPlugin *newplugin = NULL;
if (!_priv_gst_registry_chunks_load_plugin (l->registry, &tmp,
tmp + payload_len, &newplugin)) {
/* Got garbage from the child, so fail and trigger replay of plugins */
GST_ERROR_OBJECT (l->registry,
"Problems loading plugin details with tag %u from scanner", tag);
return FALSE;
}
newplugin->flags &= ~GST_PLUGIN_FLAG_CACHED;
GST_LOG_OBJECT (l->registry,
"marking plugin %p as registered as %s", newplugin,
newplugin->filename);
newplugin->registered = TRUE;
/* We got a set of plugin details - remember it for later */
l->got_plugin_details = TRUE;
} else if (entry != NULL) {
/* Create a blacklist entry for this file to prevent scanning every time */
plugin_loader_create_blacklist_plugin (l, entry);
l->got_plugin_details = TRUE;
}
if (entry != NULL) {
g_free (entry->filename);
g_free (entry);
}
/* Remove the plugin entry we just loaded */
cur = l->pending_plugins;
if (cur != NULL)
cur = g_list_delete_link (cur, cur);
l->pending_plugins = cur;
if (cur == NULL)
l->pending_plugins_tail = NULL;
break;
}
case PACKET_SYNC:
if (l->is_child) {
/* Respond with our reply - also a sync */
put_packet (l, PACKET_SYNC, tag, NULL, 0);
GST_LOG ("Got SYNC in child - replying");
} else
l->rx_got_sync = TRUE;
break;
case PACKET_VERSION:
if (l->is_child) {
/* Respond with our reply - a version packet, with the version */
const gint version_len =
sizeof (guint32) + GST_MAGIC_BINARY_VERSION_LEN;
guint8 version_info[sizeof (guint32) + GST_MAGIC_BINARY_VERSION_LEN];
memset (version_info, 0, version_len);
GST_WRITE_UINT32_BE (version_info, loader_protocol_version);
memcpy (version_info + sizeof (guint32), GST_MAGIC_BINARY_VERSION_STR,
strlen (GST_MAGIC_BINARY_VERSION_STR));
put_packet (l, PACKET_VERSION, tag, version_info, version_len);
GST_LOG ("Got VERSION in child - replying %u", loader_protocol_version);
} else {
res = check_protocol_version (l, payload, payload_len);
}
break;
default:
return FALSE; /* Invalid packet -> something is wrong */
}
return res;
}
static gboolean
read_one (GstPluginLoader * l)
{
guint64 magic;
guint32 to_read, packet_len, tag;
guint8 *in;
gint res;
to_read = HEADER_SIZE;
in = l->rx_buf;
do {
res = read (l->fd_r.fd, in, to_read);
if (G_UNLIKELY (res < 0)) {
if (errno == EAGAIN || errno == EINTR)
continue;
GST_LOG ("Failed reading packet header");
return FALSE;
}
to_read -= res;
in += res;
} while (to_read > 0);
magic = GST_READ_UINT32_BE (l->rx_buf + 8);
if (magic != HEADER_MAGIC) {
GST_WARNING
("Invalid packet (bad magic number) received from plugin scanner subprocess");
return FALSE;
}
packet_len = GST_READ_UINT32_BE (l->rx_buf + 4);
if (packet_len + HEADER_SIZE > BUF_MAX_SIZE) {
GST_WARNING
("Received excessively large packet for plugin scanner subprocess");
return FALSE;
}
tag = GST_READ_UINT24_BE (l->rx_buf + 1);
if (packet_len > 0) {
if (packet_len + HEADER_SIZE >= l->rx_buf_size) {
GST_LOG ("Expanding rx buf from %d to %d",
l->rx_buf_size, packet_len + HEADER_SIZE + BUF_GROW_EXTRA);
l->rx_buf_size = packet_len + HEADER_SIZE + BUF_GROW_EXTRA;
l->rx_buf = g_realloc (l->rx_buf, l->rx_buf_size);
}
in = l->rx_buf + HEADER_SIZE;
to_read = packet_len;
do {
res = read (l->fd_r.fd, in, to_read);
if (G_UNLIKELY (res < 0)) {
if (errno == EAGAIN || errno == EINTR)
continue;
GST_ERROR ("Packet payload read failed");
return FALSE;
}
to_read -= res;
in += res;
} while (to_read > 0);
} else {
GST_LOG ("No payload to read for 0 length packet type %d tag %u",
l->rx_buf[0], tag);
}
return handle_rx_packet (l, l->rx_buf[0], tag,
l->rx_buf + HEADER_SIZE, packet_len);
}
static gboolean
exchange_packets (GstPluginLoader * l)
{
gint res;
/* Wait for activity on our FDs */
do {
do {
res = gst_poll_wait (l->fdset, GST_SECOND);
} while (res == -1 && (errno == EINTR || errno == EAGAIN));
if (res < 0)
return FALSE;
GST_LOG ("Poll res = %d. %d bytes pending for write", res,
l->tx_buf_write - l->tx_buf_read);
if (!l->rx_done) {
if (gst_poll_fd_has_error (l->fdset, &l->fd_r) ||
gst_poll_fd_has_closed (l->fdset, &l->fd_r)) {
GST_LOG ("read fd %d closed/errored", l->fd_r.fd);
goto fail_and_cleanup;
}
if (gst_poll_fd_can_read (l->fdset, &l->fd_r)) {
if (!read_one (l))
goto fail_and_cleanup;
}
}
if (l->tx_buf_read < l->tx_buf_write) {
if (gst_poll_fd_has_error (l->fdset, &l->fd_w) ||
gst_poll_fd_has_closed (l->fdset, &l->fd_r)) {
GST_ERROR ("write fd %d closed/errored", l->fd_w.fd);
goto fail_and_cleanup;
}
if (gst_poll_fd_can_write (l->fdset, &l->fd_w)) {
if (!write_one (l))
goto fail_and_cleanup;
}
}
} while (l->tx_buf_read < l->tx_buf_write);
return TRUE;
fail_and_cleanup:
plugin_loader_cleanup_child (l);
return FALSE;
}