Make libao.conf less useless: make it possible to prepend switches to ao_open_live()

I'm too busy to rewrite my entire story. Your Trac ate my description because it contained a link. Thanks and good day, sir!

--- src/ao_private.h	Fri Aug 29 20:18:32 2003
+++ src/ao_private.h	Sat Mar  3 17:14:59 2007
@@ -61,6 +61,7 @@
 
 typedef struct ao_config {
 	char *default_driver;
+	ao_option *prepended;
 } ao_config;
 
 /* --- Functions --- */
--- src/audio_out.c	Tue Mar  9 16:35:41 2004
+++ src/audio_out.c	Sat Mar  3 17:23:18 2007
@@ -80,7 +80,8 @@
 
 static driver_list *driver_head = NULL;
 static ao_config config = {
-	NULL /* default_driver */
+	NULL /* default_driver */,
+	NULL /* prepended options */
 };
 
 static ao_info **info_table = NULL;
@@ -446,6 +447,7 @@
 static ao_device* _open_device(int driver_id, ao_sample_format *format, 
 			       ao_option *options, FILE *file)
 {
+	ao_option *prepended = config.prepended;
 	ao_functions *funcs;
 	driver_list *driver;
 	ao_device *device;
@@ -486,6 +488,12 @@
 		return NULL; /* Couldn't init internal memory */
 	}
 	
+	/* Default options */
+	while (prepended != NULL) {
+		/* Ignore errors */
+		funcs->set_option(device, prepended->key, prepended->value);
+		prepended = prepended->next;
+	}
 	/* Load options */
 	while (options != NULL) {
 		if (!funcs->set_option(device, options->key, options->value)) {
--- src/config.c	Thu Aug  7 17:44:36 2003
+++ src/config.c	Sat Mar  3 17:17:28 2007
@@ -23,6 +23,7 @@
  *
  */
 
+#include "ao/ao.h"
 #include "ao_private.h"
 #include <stdio.h>
 #include <stdlib.h>
@@ -52,7 +53,8 @@
 int read_config_file(ao_config *config, const char *config_file)
 {
 	FILE *fp;
-	char line[LINE_LEN];
+	ao_option *aopt;
+	char line[LINE_LEN], *split;
 	int end;
 	
 	
@@ -60,15 +62,32 @@
 		return 0; /* Can't open file */
 	
 	while (fgets(line, LINE_LEN, fp)) {
-		/* All options are key=value */
+		/* Remove trailing newline */
+		end = strlen(line);
+		if (line[end-1] == '\n')
+			line[end-1] = '\0';
 		
 		if (strncmp(line, "default_driver=", 15) == 0) {
+			/* Store default driver for efficiency */
 			free(config->default_driver);
-			end = strlen(line);
-			if (line[end-1] == '\n')
-				line[end-1] = 0; /* Remove trailing newline */
-
 			config->default_driver = strdup(line+15);
+		} else {
+			/* All options are key=value */
+			split = strchr(line, '=');
+			if (split == NULL || split[1] == '\0')
+				continue;
+
+			/* Add new option to the list */
+			aopt = malloc(sizeof(ao_option));
+			if (aopt == NULL)
+				continue;
+			aopt->next = config->prepended;
+			config->prepended = aopt;
+
+			/* Split line in two and copy key/value */
+			*split = '\0';
+			aopt->key = strdup(line);
+			aopt->value = strdup(split + 1);
 		}
 	}