From: Andre Noll <maan@systemlinux.org>
Date: Thu, 4 Nov 2010 22:54:23 +0000 (+0100)
Subject: Change the ->open method of writers to void.
X-Git-Tag: v0.4.5~4^2~6
X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=commitdiff_plain;h=d56a8447f418cf9046077e743772a416b6f7b826

Change the ->open method of writers to void.

These methods always succeed. Add missing documentation of the public
register_writer_node() function while we're at it.
---

diff --git a/alsa_write.c b/alsa_write.c
index aa772daa..b685e4f7 100644
--- a/alsa_write.c
+++ b/alsa_write.c
@@ -143,10 +143,9 @@ static int alsa_init(struct private_alsa_write_data *pad,
 }
 
 /* Open an instance of the alsa writer. */
-static int alsa_open(struct writer_node *wn)
+static void alsa_open(struct writer_node *wn)
 {
 	wn->private_data = para_calloc(sizeof(struct private_alsa_write_data));
-	return 1;
 }
 
 static void alsa_write_pre_select(struct sched *s, struct task *t)
diff --git a/file_write.c b/file_write.c
index 7497dfaa..7bc1e437 100644
--- a/file_write.c
+++ b/file_write.c
@@ -50,13 +50,12 @@ __must_check __malloc static char *random_filename(void)
 	return result;
 }
 
-static int file_write_open(struct writer_node *wn)
+static void file_write_open(struct writer_node *wn)
 {
 	struct private_file_write_data *pfwd = para_calloc(sizeof(*pfwd));
 
 	wn->private_data = pfwd;
 	pfwd->fd = -1;
-	return 0;
 }
 
 static int prepare_output_file(struct writer_node *wn)
diff --git a/oss_write.c b/oss_write.c
index 5bc41bcc..2d820d33 100644
--- a/oss_write.c
+++ b/oss_write.c
@@ -199,14 +199,12 @@ out:
 		btr_remove_node(btrn);
 }
 
-static int oss_open(struct writer_node *wn)
+static void oss_open(struct writer_node *wn)
 {
-	struct private_oss_write_data *powd;
+	struct private_oss_write_data *powd = para_calloc(sizeof(*powd));
 
-	powd = para_calloc(sizeof(*powd));
-	wn->private_data = powd;
 	powd->fd = -1;
-	return 1;
+	wn->private_data = powd;
 }
 
 __malloc static void *oss_parse_config_or_die(const char *options)
diff --git a/osx_write.c b/osx_write.c
index b0dfa89b..c2b7b2f4 100644
--- a/osx_write.c
+++ b/osx_write.c
@@ -187,13 +187,12 @@ static OSStatus osx_callback(void * inClientData,
 #define ENDIAN_FLAGS 0
 #endif
 
-static int osx_write_open(struct writer_node *wn)
+static void osx_write_open(struct writer_node *wn)
 {
 	struct private_osx_write_data *powd = para_calloc(sizeof(*powd));
 
 	wn->private_data = powd;
 	init_buffers(wn);
-	return 0;
 }
 
 static int core_audio_init(struct writer_node *wn)
diff --git a/write.h b/write.h
index fd0f4f6b..da6f1e75 100644
--- a/write.h
+++ b/write.h
@@ -53,11 +53,13 @@ struct writer {
 	/**
 	 * Open one instance of this writer.
 	 *
-	 * This function should perform any work necessary to write the incoming
-	 * stream. To this aim, it may allocate its private data structure and store
-	 * a pointer to that structure via the given writer_node parameter.
+	 * Perform any preparations needed to write the incoming stream.
+	 * Usually this function just allocates its private data structure and
+	 * stores a pointer to that structure in the ->private data of the
+	 * given parameter. This function must either succeed or terminate the
+	 * process.
 	 */
-	int (*open)(struct writer_node *);
+	void (*open)(struct writer_node *);
 	/**
 	 * Prepare the fd sets for select.
 	 *
diff --git a/write_common.c b/write_common.c
index fb7f4775..5bfba37d 100644
--- a/write_common.c
+++ b/write_common.c
@@ -73,18 +73,26 @@ void *check_writer_arg(const char *wa, int *writer_num)
 	return NULL;
 }
 
+/**
+ * Open a writer node and register the corresponding task.
+ *
+ * \param wn The writer node to open.
+ * \param parent The parent btr node (the source for the writer node).
+ *
+ * The configuration of the writer node stored in \p wn->conf must be
+ * initialized before this function may be called.
+ */
 void register_writer_node(struct writer_node *wn, struct btr_node *parent)
 {
 	struct writer *w = writers + wn->writer_num;
 	char *name = make_message("%s writer", writer_names[wn->writer_num]);
-	int ret;
 
 	wn->btrn = btr_new_node(&(struct btr_node_description)
 		EMBRACE(.name = name, .parent = parent,
 		.handler = w->execute, .context = wn));
 	strcpy(wn->task.status, name);
 	free(name);
-	ret = w->open(wn);
+	w->open(wn);
 	wn->task.post_select = w->post_select;
 	wn->task.pre_select = w->pre_select;
 	register_task(&wn->task);