adding alsa-plugin and patching alsa so that you can tell it about additional plugins

svn path=/nixpkgs/trunk/; revision=17316
2009-09-20 21:54:23 +00:00
parent 88e66ae7f4
commit 862fcb0252
5 changed files with 100 additions and 0 deletions
@@ -0,0 +1,64 @@
+diff --git a/src/pcm/pcm.c b/src/pcm/pcm.c
+index 74d1d1a..17ffb12 100644
+--- a/src/pcm/pcm.c
+++ b/src/pcm/pcm.c
+@@ -2042,6 +2042,19 @@ static const char *const build_in_pcms[] = {
+ 	NULL
+ };
+ 
+
+// helper funcion used below
+int file_exists(const char * filename)
+{
+	FILE * file;
+	if (file = fopen(filename, "r"))
+	{
+		fclose(file);
+		return 1;
+	}
+	return 0;
+}
+
+ static int snd_pcm_open_conf(snd_pcm_t **pcmp, const char *name,
+ 			     snd_config_t *pcm_root, snd_config_t *pcm_conf,
+ 			     snd_pcm_stream_t stream, int mode)
+@@ -2141,8 +2154,38 @@ static int snd_pcm_open_conf(snd_pcm_t **pcmp, const char *name,
+ 				err = -ENOMEM;
+ 				goto _err;
+ 			}
+-			lib = buf1;
+ 			sprintf(buf1, "%s/libasound_module_pcm_%s.so", ALSA_PLUGIN_DIR, str);
+			if (!file_exists(buf1)){
+				// try to locate plugin in one of ALSA_PLUGIN_DIRS which is colon separated list of paths
+				char * pdirs = getenv("ALSA_PLUGIN_DIRS");
+
+				if (pdirs){ // env var set?
+					char * saveptr;
+					while (1) {
+						char * dir_tok = strtok_r(pdirs, "::::", &saveptr); // "::::" to work around bug in glibc and -O2 ? ":" seems to cause a segfault
+						if (dir_tok == NULL)
+                            break;
+						char * so_file = malloc(strlen(str) + strlen(dir_tok) + 32);
+						if (so_file == NULL) {
+							err = -ENOMEM;
+							goto _err;
+						}
+
+						sprintf(so_file, "%s/libasound_module_pcm_%s.so", dir_tok, str);
+
+						if (file_exists(so_file)){
+
+							free(buf1);
+							buf1 = so_file;
+							break;
+						} else {
+							free (so_file);
+						}
+						pdirs = NULL;
+					}
+				}
+			}
+			lib = buf1;
+ 		}
+ 	}
+ #ifndef PIC
@@ -10,6 +10,7 @@ stdenv.mkDerivation {
  # Fix pcm.h file in order to prevent some compilation bugs
  patchPhase = ''
    sed -i -e 's|//int snd_pcm_mixer_element(snd_pcm_t \*pcm, snd_mixer_t \*mixer, snd_mixer_elem_t \*\*elem);|/\*int snd_pcm_mixer_element(snd_pcm_t \*pcm, snd_mixer_t \*mixer, snd_mixer_elem_t \*\*elem);\*/|' include/pcm.h
+    unset patchPhase; patchPhase
  '';
  meta = {
    description = "ALSA, the Advanced Linux Sound Architecture libraries";
@@ -21,4 +22,10 @@ stdenv.mkDerivation {

    homepage = http://www.alsa-project.org/;
  };
+
+  patches = [
+    /* allow specifying alternatives alsa plugin locations using
+       export ALSA_PLUGIN_DIRS=$(nix-build -A alsaPlugins)/lib/alsa-lib */
+    ./alsa-plugin-dirs.patch
+  ];
 }