Add ctl ASCII parser code

Added a few helper functions that have been added some time ago to
alsa-lib for dealing with ASCII <-> ctl conversions.  They are mostly
used by amixer.

They are enabled via --enable-ctlasciiparser configure option.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

3 files changed, 140 insertions, 0 deletions

diff --git a/configure.ac b/configure.ac
index eae1b81..19aff7e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -137,6 +137,11 @@ AC_ARG_ENABLE(abicheck,
 		 [enable library ABI check]),
   abicheck="$enableval", abicheck="no")
 
+AC_ARG_ENABLE(ctlasciiparser,
+  AS_HELP_STRING([--enable-ctlasciiparser],
+		 [enable ctl ASCII parser (for amixer)]),
+  ctlasciiparser="$enableval", ctlasciiparser="no")
+
 AC_ARG_ENABLE(everything,
   AS_HELP_STRING([--enable-everything],
 		 [enable everything :)]),
@@ -160,6 +165,7 @@ if test "$everything" = "yes"; then
   support_float="yes"
   support_4bit="yes"
   abicheck="yes"
+  ctlasciiparser="yes"
 fi
 
 SALSA_DEPLIBS=""
@@ -246,6 +252,13 @@ else
 fi
 AC_SUBST(SALSA_CHECK_ABI)
 
+if test "$ctlasciiparser" = "yes"; then
+  SALSA_CTL_ASCII_PARSER=1
+else
+  SALSA_CTL_ASCII_PARSER=0
+fi
+AC_SUBST(SALSA_CTL_ASCII_PARSER)
+
 if test "$delight_valgrind" = "yes"; then
   AC_DEFINE(DELIGHT_VALGRIND)
 fi
@@ -305,3 +318,4 @@ echo "  - Mark deprecated attribute: $markdeprecated"
 echo "  - Support string-output via snd_output: $output_buffer"
 echo "  - Support floating-point: $support_float"
 echo "  - Enable library ABI check: $abicheck"
+echo "  - Support ctl ASCII parser: $ctlasciiparser"
diff --git a/src/control.c b/src/control.c
index 4a7666f..1f19431 100644
--- a/src/control.c
+++ b/src/control.c
@@ -764,3 +764,126 @@ int snd_tlv_convert_from_dB(unsigned int *tlv, long rangemin, long rangemax,
 }
 
 #endif /* TLV */
+
+#if SALSA_CTL_ASCII_PARSER
+char *snd_ctl_ascii_elem_id_get(snd_ctl_elem_id_t *id)
+{
+	char buf[256];
+	int len;
+
+	len = snprintf(buf, sizeof(buf), "numid=%u,iface=%s,name='%s'",
+		       id->numid, _snd_ctl_elem_iface_names[id->iface],
+		       id->name);
+	if (len < sizeof(buf) && id->index > 0)
+		len += snprintf(buf + len, sizeof(buf) - len,
+				",index=%d", id->index);
+	if (len < sizeof(buf) && id->device > 0)
+		len += snprintf(buf + len, sizeof(buf) - len,
+				",device=%d", id->device);
+	if (len < sizeof(buf) && id->subdevice > 0)
+		len += snprintf(buf + len, sizeof(buf) - len,
+				",subdevice=%d", id->subdevice);
+	return strdup(buf);
+}
+
+int snd_ctl_ascii_elem_id_parse(snd_ctl_elem_id_t *dst, const char *str)
+{
+	char iface[20];
+	char *p, *s = (char *)str;
+	int i;
+
+	while ((p = strsep(&s, ",")) != NULL) {
+		if (sscanf(p, "iface=%20[^,]", iface) == 1) {
+			for (i = 0; i <= SND_CTL_ELEM_IFACE_LAST; i++) {
+				if (!strcmp(iface,
+					    _snd_ctl_elem_iface_names[i])) {
+					dst->iface = i;
+					break;
+				}
+			}
+			if (i > SND_CTL_ELEM_IFACE_LAST)
+				return -EINVAL;
+			continue;
+		}
+		if (sscanf(p, "name='%42[^']", dst->name) == 1)
+			continue;
+		if (sscanf(p, "numid=%d", &dst->numid) == 1)
+			continue;
+		if (sscanf(p, "index=%d", &dst->index) == 1)
+			continue;
+		if (sscanf(p, "device=%d", &dst->device) == 1)
+			continue;
+		if (sscanf(p, "subdevice=%d", &dst->subdevice) == 1)
+			continue;
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static int match_yes(const char *ptr)
+{
+	static const char * const yes[] = {
+		"on", "up", "yes", "true", NULL,
+	};
+	const char * const *p;
+
+	for (p = yes; *p; p++)
+		if (strncasecmp(ptr, *p, strlen(*p)))
+			return 1;
+	return 0;
+}
+
+static int get_enum_index(snd_ctl_t *handle, snd_ctl_elem_info_t *info,
+			  const char *ptr)
+{
+	int i;
+
+	for (i = 0; i < info->value.enumerated.items; i++) {
+		info->value.enumerated.item = i;
+		if (snd_ctl_elem_info(handle, info) < 0)
+			return -1;
+		if (!strncmp(ptr, info->value.enumerated.name,
+			     strlen(info->value.enumerated.name)))
+			return i;
+	}
+	return -1;
+}
+
+int snd_ctl_ascii_value_parse(snd_ctl_t *handle,
+			      snd_ctl_elem_value_t *dst,
+			      snd_ctl_elem_info_t *info,
+			      const char *ptr)
+{
+	int idx = 0;
+	int tmp;
+
+	for (idx = 0; idx < info->count && idx < 128 && *ptr; idx++) {
+		switch (info->type) {
+		case SND_CTL_ELEM_TYPE_BOOLEAN:
+			if (!strncasecmp(ptr, "toggle", 6))
+				tmp = !dst->value.integer.value[idx];
+			else if (match_yes(ptr) || *ptr == '1')
+				tmp = 1;
+			else
+				tmp = 0;
+			dst->value.integer.value[idx] = tmp;
+			break;
+		case SND_CTL_ELEM_TYPE_INTEGER:
+			dst->value.integer.value[idx] = strtol(ptr, NULL, 0);
+			break;
+		case SND_CTL_ELEM_TYPE_INTEGER64:
+			dst->value.integer.value[idx] = strtoll(ptr, NULL, 0);
+			break;
+		case SND_CTL_ELEM_TYPE_ENUMERATED:
+			tmp = get_enum_index(handle, info, ptr);
+			if (tmp < 0)
+				return -EINVAL;
+			dst->value.enumerated.item[idx] = tmp;
+			break;
+		}
+		while (*ptr && *ptr != ',')
+			ptr++;
+	}
+	return 0;
+}
+#endif /* SALSA_CTL_ASCII_PARSER */
diff --git a/src/recipe.h.in b/src/recipe.h.in
index bbbdee3..620745f 100644
--- a/src/recipe.h.in
+++ b/src/recipe.h.in
@@ -31,6 +31,9 @@
 /* Enable library ABI check */
 #define SALSA_CHECK_ABI		@SALSA_CHECK_ABI@
 
+/* Support ASCII value parser for ctl */
+#define SALSA_CTL_ASCII_PARSER	@SALSA_CTL_ASCII_PARSER@
+
 /* Default device path prefix */
 #define SALSA_DEVPATH "@DEVPATH@"