From: Ralph Ronnquist <ralph.ronnquist@gmail.com>
Date: Wed, 26 Apr 2023 12:46:00 +0000 (+1000)
Subject: Expand higher API (set config string).
X-Git-Url: https://git.rrq.au/?a=commitdiff_plain;h=4ec2385eae5c542c723ba17c0bb0682d71dcbf4e;p=rrq%2Flsp-utils.git

Expand higher API (set config string).
---

diff --git a/lsp-alsa/libasound.lsp b/lsp-alsa/libasound.lsp
index ef4a571..42d7f35 100644
--- a/lsp-alsa/libasound.lsp
+++ b/lsp-alsa/libasound.lsp
@@ -2,9 +2,6 @@
 ;; providing a higher level ALSA API over a lower level libasound API
 ;; on top of a libc API.
 
-;; This implementation expects lib-utils.lsp to be loaded beforehand
-;; for providing the <prog1> and <loginfo> functions.
-
 ;;=====================================================================
 ; The libc context is an API towards libc.so.6 dynamic library which
 ; offers the basic C functions
@@ -40,7 +37,7 @@
 (if (exec "find /lib /usr/lib -name 'libasound.so*' -type f")
     (constant 'LIB ($it 0))
   (die 1 "Cannot find libasound.so"))
-(when (ENV "LOG") (println "Using " LIB))
+(when (env "LOG") (println "Using " LIB))
 
 ;; == Global functions
 ; https://alsa-project.org/alsa-doc/alsa-lib/group___global.html
@@ -156,10 +153,16 @@
 
 ;;; PCM API
 
-;; Opens a PCM
+;; Opens a named PCM and return handle
 (define (snd_pcm_open NAME STREAM-TYPE MODE)
-  (let ((PCM (pack "Lu" 0)))
-    (when (= (libasound:snd_pcm_open (address PCM) NAME STREAM-TYPE MODE))
-      ((unpack "Lu" PCM) 0))))
+  (let ((DATA (pack "Lu" 0)))
+    (when (= (libasound:snd_pcm_open (address DATA) NAME STREAM-TYPE MODE))
+      ((unpack "LuLu" (address DATA)) 0))))
+
+;; Set the value of given path as given.
+(define (set_config_string PATH VALUE)
+  (let ((DATA (pack "Lu" 0)) (TREE (libasound:snd_config@)))
+    (when (= (libasound:snd_config_search TREE PATH (address DATA)))
+      (libasound:snd_config_set_string ((unpack "Lu" DATA) 0) VALUE))))
 
 "libasound.lsp"