lyrics: replaced asserts with error handler

Handle missing artist and/or title for lyrics by defining an empty list of
plugins that fails almost immediately. Note that args in lyrics_load may now
start with NULL as the first array element. make_argv() in plugin.c made the
assumption that at least one argument is passed. If the first argument is
NULL a bogus pointer is returned by make_argv(). By converting do {} while
into while {}, we allow the first argument to be NULL.

diff --git a/src/lyrics.c b/src/lyrics.c
index 43800eb48fb6d128dd65623f4084ee82a5d28899..3f73690fd13fb6301555434ad663df3134a12aaf 100644 (file)
--- a/src/lyrics.c
+++ b/src/lyrics.c
@@ -22,16 +22,18 @@
 
 #include <assert.h>
 
-static struct plugin_list plugins;
+static struct plugin_list empty, plugins;
 
 void lyrics_init(void)
 {
+       plugin_list_init(&empty);
        plugin_list_init(&plugins);
        plugin_list_load_directory(&plugins, LYRICS_PLUGIN_DIR);
 }
 
 void lyrics_deinit(void)
 {
+       plugin_list_deinit(&empty);
        plugin_list_deinit(&plugins);
 }
 
@@ -41,8 +43,8 @@ lyrics_load(const char *artist, const char *title,
 {
        const char *args[3] = { artist, title, NULL };
 
-       assert(artist != NULL);
-       assert(title != NULL);
+       if (artist == NULL || title == NULL)
+               return plugin_run(&empty, args, callback, data);
 
        return plugin_run(&plugins, args, callback, data);
 }

diff --git a/src/plugin.c b/src/plugin.c
index d7849009887ae92e9c1fba785376a2b465e6b098..d89e210b1bd3e7bf456817b4ac0557263491ee22 100644 (file)
--- a/src/plugin.c
+++ b/src/plugin.c
@@ -340,9 +340,8 @@ make_argv(const char*const* args)
        /* reserve space for the program name */
        *ret++ = NULL;
 
-       do {
+       while (*args != NULL)
                *ret++ = g_strdup(*args++);
-       } while (*args != NULL);
 
        /* end of argument vector */
        *ret++ = NULL;