X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=grab_client.c;h=9109c2f8f6c5f1978eddd356ff7f8e979d73dd8a;hp=d1ef43f95bba34cc43881ec779976f5c3d797e50;hb=bda95f9508b456dcea89d300f6d4104e30ab9f3e;hpb=d5d96c6c65b47a34136bc04420bffd38e947bfea

diff --git a/grab_client.c b/grab_client.c
index d1ef43f9..9109c2f8 100644
--- a/grab_client.c
+++ b/grab_client.c
@@ -1,24 +1,20 @@
 /*
- * Copyright (C) 2006-2009 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2006-2011 Andre Noll <maan@systemlinux.org>
  *
  * Licensed under the GPL v2. For licencing details see COPYING.
  */
 
-/**
- * \file grab_client.c Functions for grabbing the stream at any position
- * in a filter chain.
- *
- * \sa filter_chain filter_chain_info filter.
- */
+/** \file grab_client.c Functions for grabbing the audio stream. */
 
 #include <regex.h>
 #include <sys/types.h>
-#include <dirent.h>
+#include <stdbool.h>
 
 #include "para.h"
 #include "list.h"
 #include "sched.h"
 #include "ggo.h"
+#include "buffer_tree.h"
 #include "filter.h"
 #include "grab_client.h"
 #include "audiod.h"
@@ -26,144 +22,200 @@
 #include "string.h"
 #include "fd.h"
 
-/** Grab clients that are not yet attached to a filter node. */
-static struct list_head inactive_grab_client_list;
-
-static int max_num_filters(void)
-{
-	int i, ret = 0;
+/**
+ * How to handle blocking writes for the grab client fds.
+ */
+enum grab_mode {
+	/** Ignore the data and do not write. */
+	GM_SLOPPY,
+	/** Write anyway (default). */
+	GM_AGGRESSIVE,
+	/** Close fd if write would block. */
+	GM_PEDANTIC,
+};
 
-	for (i = 0; audio_formats[i]; i++) {
-		PARA_INFO_LOG("%s filter chain length: %d\n", audio_formats[i],
-			num_filters(i));
-		ret = PARA_MAX(ret, num_filters(i));
-	}
-	PARA_INFO_LOG("maximal filter chain length: %d\n", ret);
-	return ret;
-}
+/** Flags specified as arguments to the grab command. */
+enum grab_flags {
+	/** Stop grabbing if audio file changes. */
+	GF_ONE_SHOT = 1,
+};
 
-static struct filter_node *find_filter_node(int format, int filternum)
-{
-	int i;
+/** Describes one active grab client. */
+struct grab_client {
+	/* The value of the -p option. */
+	char *parent;
+	/* The value of the -n option. */
+	char *name;
+	/** The file descriptor to send the grabbed stream to. */
+	int fd;
+	/** See \ref grab_mode. */
+	enum grab_mode mode;
+	/** Flags given at the command line. */
+	enum grab_flags flags;
+	/** The point of the grab client's node in the buffer tree. */
+	struct btr_node *btrn;
+	/* The task of this grab client. */
+	struct task task;
+	/** Belongs to either the active or the inactive list. */
+	struct list_head node;
+};
 
-	FOR_EACH_SLOT(i) {
-		struct slot_info *s = &slot[i];
-		if (s->format < 0 || !s->fc)
-			continue;
-		if (format >= 0 && s->format != format)
-			continue;
-		if (num_filters(i) <= filternum)
-			continue;
-		/* success */
-		return  s->fc->filter_nodes + filternum;
-	}
-	return NULL;
-}
+/* Grab clients that are attached to a btr node. */
+static INITIALIZED_LIST_HEAD(active_grab_client_list);
+/* Grab clients that are not currently attached any btr node. */
+static INITIALIZED_LIST_HEAD(inactive_grab_client_list);
 
-static int gc_write(char *buf, size_t len, struct filter_callback *fcb)
+static int gc_write(struct grab_client *gc, char *buf, size_t len)
 {
-	struct grab_client *gc = container_of(fcb, struct grab_client, fcb);
-	size_t written = 0;
+	int ret = write_ok(gc->fd);
 
-	while (written < len) {
-		int ret = write_ok(gc->fd);
-		if (ret < 0)
+	if (ret < 0)
+		goto err;
+	if (ret == 0) { /* fd not ready */
+		if (gc->mode == GM_PEDANTIC)
 			goto err;
-		if (ret == 0) { /* fd not ready */
-			if (gc->mode == GM_PEDANTIC)
-				goto err;
-			if (gc->mode == GM_SLOPPY)
-				return 1;
-		}
-		ret = write(gc->fd, buf + written, len - written);
-		if (ret < 0) {
-			if (errno != EAGAIN && errno != EINTR)
-				goto err;
-			if (gc->mode == GM_PEDANTIC)
-				goto err;
-			if (gc->mode == GM_SLOPPY)
-				return 1;
-		} else
-			written += ret;
+		if (gc->mode == GM_SLOPPY)
+			return len;
 	}
-	return 1;
+	ret = write_nonblock(gc->fd, buf, len);
+	if (ret < 0)
+		goto err;
+	if (ret > 0)
+		return ret;
+	if (ret == 0) {
+		if (gc->mode == GM_PEDANTIC)
+			goto err;
+		if (gc->mode == GM_SLOPPY)
+			return len;
+	}
+	return 0;
 err:
-	gc->error = -E_GC_WRITE;
 	return -E_GC_WRITE;
 }
 
-static void add_inactive_gc(struct grab_client *gc)
-{
-	PARA_INFO_LOG("adding grab client %p (fd %d) to inactive list\n",
-		gc, gc->fd);
-	para_list_add(&gc->node, &inactive_grab_client_list);
-}
-
-static void gc_close(struct filter_callback *fcb)
+static void gc_pre_select(struct sched *s, struct task *t)
 {
-	struct grab_client *gc = container_of(fcb, struct grab_client, fcb);
+	struct grab_client *gc = container_of(t, struct grab_client, task);
+	int ret = btr_node_status(gc->btrn, 0, BTR_NT_LEAF);
 
-	if ((gc->flags & GF_ONE_SHOT) || gc->error < 0) {
-		PARA_INFO_LOG("closing fd %d (grab client %p)\n", gc->fd, gc);
-		close(gc->fd);
-		free(gc);
+	if (ret == 0)
 		return;
-	}
-	add_inactive_gc(gc);
+	if (ret < 0)
+		sched_min_delay(s);
+	para_fd_set(gc->fd, &s->wfds, &s->max_fileno);
 }
 
+/*
+ * We need this forward declaration as post_select() needs
+ * activate_grab_client and vice versa.
+ */
+static void gc_post_select(struct sched *s, struct task *t);
+
 /**
- * Move a grab client from the inactive list to a filter node.
+ * Move a grab client to the active list and start it.
  *
  * \param gc The grab client to activate.
- * \param fn The filter node \a gc gets attached to.
- *
- * \sa filter_node::callbacks, inactive_grab_client_list.
  */
-void activate_grab_client(struct grab_client *gc, struct filter_node *fn)
+static void gc_activate(struct grab_client *gc)
 {
-	PARA_INFO_LOG("activating %p (fd %d, filter node: %p)\n", gc, gc->fd, fn);
-	list_del(&gc->node);
-	para_list_add(&gc->fcb.node, &fn->callbacks);
+	struct btr_node *root = audiod_get_btr_root(), *parent;
+	char *name = gc->name? gc->name : "grab";
+
+	if (!root)
+		return;
+	parent = btr_search_node(gc->parent, root);
+	if (!parent)
+		return;
+	PARA_INFO_LOG("activating fd %d\n", gc->fd);
+	list_move(&gc->node, &active_grab_client_list);
+	gc->btrn = btr_new_node(&(struct btr_node_description)
+		EMBRACE(.name = name, .parent = parent));
+	gc->task.pre_select = gc_pre_select;
+	gc->task.post_select = gc_post_select;
+	snprintf(gc->task.status, sizeof(gc->task.status) - 1, "%s", name);
+	gc->task.status[sizeof(gc->task.status) - 1] = '\0';
+	gc->task.error = 0;
+	register_task(&gc->task);
 }
 
 /**
  * Activate inactive grab clients if possible.
  *
- * \param audio_format_num The number of the audio format of the new audio file.
- * \param fc The filter chain containing the activated filters.
- *
  * This is called from audiod.c when the current audio file changes. It loops
  * over all inactive grab clients and checks each grab client's configuration
  * to determine if the client in question wishes to grab the new stream.  If
- * yes, this grab client is moved from the inactive grab client list to an
- * appropriate filter_node.
+ * yes, this grab client is moved from the inactive to the active grab client list.
  *
- * \sa filter_chain_info::filters, inactive_grab_client_list,
- * activate_grab_client.
+ * This function also garbage collects all grab clients whose tasks have been
+ * unscheduled.
  */
-void activate_inactive_grab_clients(int audio_format_num,
-		struct filter_chain *fc)
+void activate_grab_clients(void)
 {
 	struct grab_client *gc, *tmp;
-	struct filter_node *fn;
 
 	list_for_each_entry_safe(gc, tmp, &inactive_grab_client_list, node) {
-		if (gc->audio_format_num >= 0 && gc->audio_format_num !=
-				audio_format_num)
-			continue;
-		if (gc->filter_num >= num_filters(audio_format_num))
+		if (gc->fd < 0) {
+			list_del(&gc->node);
+			free(gc);
 			continue;
-		fn = fc->filter_nodes + gc->filter_num;
-		activate_grab_client(gc, fn);
+		}
+		gc_activate(gc);
+	}
+}
+
+static int gc_close(struct grab_client *gc, int err)
+{
+	btr_remove_node(gc->btrn);
+	btr_free_node(gc->btrn);
+	gc->btrn = NULL;
+	PARA_INFO_LOG("closing gc: %s\n", para_strerror(-err));
+	list_move(&gc->node, &inactive_grab_client_list);
+	if (err == -E_GC_WRITE || (gc->flags & GF_ONE_SHOT)) {
+		/*
+		 * We must not free the gc structure here as it contains ->task
+		 * which is still used because this function is called from
+		 * post_select().
+		 */
+		close(gc->fd);
+		gc->fd = -1;
+		free(gc->parent);
+		free(gc->name);
+		return 1;
 	}
+	return 0;
+}
+
+static void gc_post_select(__a_unused struct sched *s, struct task *t)
+{
+	struct grab_client *gc = container_of(t, struct grab_client, task);
+	struct btr_node *btrn = gc->btrn;
+	int ret;
+	size_t sz;
+	char *buf;
+
+	t->error = 0;
+	ret = btr_node_status(btrn, 0, BTR_NT_LEAF);
+	if (ret == 0)
+		return;
+	if (ret < 0)
+		goto err;
+	sz = btr_next_buffer(btrn, &buf);
+	assert(sz != 0);
+	ret = gc_write(gc, buf, sz);
+	if (ret < 0)
+		goto err;
+	if (ret > 0)
+		btr_consume(btrn, ret);
+	return;
+err:
+	gc_close(gc, ret);
+	t->error = ret;
 }
 
-static int check_gc_args(int argc, char **argv, struct grab_client *gc)
+static int gc_check_args(int argc, char **argv, struct grab_client *gc)
 {
-	int i, ret;
+	int i;
 
-	gc->audio_format_num = -1; /* default: grab any audio format */
 	for (i = 1; i < argc; i++) {
 		const char *arg = argv[i];
 		if (arg[0] != '-')
@@ -172,16 +224,6 @@ static int check_gc_args(int argc, char **argv, struct grab_client *gc)
 			i++;
 			break;
 		}
-		if (!strncmp(arg, "-n=", 3)) {
-			ret = para_atoi32(arg + 3, &gc->filter_num);
-			if (ret < 0)
-				return ret;
-			if (gc->filter_num < 0)
-				return -E_BAD_GC_FILTER_NUM;
-			if (gc->filter_num >= max_num_filters())
-				return -E_BAD_GC_FILTER_NUM;
-			continue;
-		}
 		if (!strncmp(arg, "-m", 2)) {
 			if (*(arg + 3))
 				return -E_GC_SYNTAX;
@@ -199,19 +241,16 @@ static int check_gc_args(int argc, char **argv, struct grab_client *gc)
 				return -E_GC_SYNTAX;
 			}
 		}
-		if (!strcmp(arg, "-i")) {
-			gc->flags |= GF_INPUT_GRAB;
-			continue;
-		}
 		if (!strcmp(arg, "-o")) {
 			gc->flags |= GF_ONE_SHOT;
 			continue;
 		}
-		if (!strncmp(arg, "-f=", 3)) {
-			ret = get_audio_format_num(arg + 3);
-			if (ret < 0)
-				return ret;
-			gc->audio_format_num = ret;
+		if (!strncmp(arg, "-p=", 3)) {
+			gc->parent = para_strdup(arg + 3);
+			continue;
+		}
+		if (!strncmp(arg, "-n=", 3)) {
+			gc->name = para_strdup(arg + 3);
 			continue;
 		}
 		return -E_GC_SYNTAX;
@@ -230,47 +269,26 @@ static int check_gc_args(int argc, char **argv, struct grab_client *gc)
  *
  * If the command line options given by \a argc and \a argv are valid.
  * allocate a struct grab_client and initialize it with this valid
- * configuration. Moreover, add the new grab client to the inactive list.
+ * configuration.
  *
- * \return Standard.
+ * If the new grab client can be added to an existing buffer tree, activate it.
+ * Otherwise, add it to the inactive list for later activation.
  *
- * \sa grab_client, inactive_grab_client_list, activate_grab_client,
- * filter_node::callbacks.
+ * \return Standard.
  */
 int grab_client_new(int fd, int argc, char **argv)
 {
 	int ret;
 	struct grab_client *gc = para_calloc(sizeof(struct grab_client));
-	struct filter_node *fn;
 
-	ret = check_gc_args(argc, argv, gc);
+	ret = gc_check_args(argc, argv, gc);
 	if (ret < 0)
 		goto err_out;
-	if (gc->flags & GF_INPUT_GRAB)
-		gc->fcb.input_cb = gc_write;
-	else
-		gc->fcb.output_cb = gc_write;
 	gc->fd = fd;
-	gc->fcb.close = gc_close;
-	fn = find_filter_node(gc->audio_format_num, gc->filter_num);
-	if (fn)
-		para_list_add(&gc->fcb.node, &fn->callbacks);
-	else
-		add_inactive_gc(gc);
+	para_list_add(&gc->node, &inactive_grab_client_list);
+	gc_activate(gc);
 	return 1;
 err_out:
 	free(gc);
 	return ret;
 }
-
-/**
- * Initialize the grabbing subsystem.
- *
- * This has to be called once during startup before any other function from
- * grab_client.c may be used. It initializes \a inactive_grab_client_list.
- */
-void init_grabbing(void)
-{
-	PARA_INFO_LOG("grab init\n");
-	INIT_LIST_HEAD(&inactive_grab_client_list);
-}