ucm: define and describe Syntax 7

- for new macro argument substitution
- for new Path condition fields substitutions

Link: https://github.com/alsa-project/alsa-ucm-conf/pull/411
Link: https://github.com/alsa-project/alsa-lib/issues/395
Signed-off-by: Jaroslav Kysela <perex@perex.cz>

src/ucm/parser.c

@@ -454,11 +454,16 @@ static int evaluate_macro1(snd_use_case_mgr_t *uc_mgr,
 		err = snd_config_get_ascii(n, &var);
 		if (err < 0)
 			goto __err_path;
-		err = uc_mgr_get_substituted_value(uc_mgr, &var2, var);
-		free(var);
-		if (err >= 0) {
-			err = uc_mgr_set_variable(uc_mgr, name, var2);
-			free(var2);
+		if (uc_mgr->conf_format < 7) {
+			err = uc_mgr_set_variable(uc_mgr, name, var);
+			free(var);
+		} else {
+			err = uc_mgr_get_substituted_value(uc_mgr, &var2, var);
+			free(var);
+			if (err >= 0) {
+				err = uc_mgr_set_variable(uc_mgr, name, var2);
+				free(var2);
+			}
 		}
 		if (err < 0)
 			goto __err_path;

src/ucm/ucm_cond.c

@@ -293,9 +293,13 @@ static int if_eval_path(snd_use_case_mgr_t *uc_mgr, snd_config_t *eval)
 		return -EINVAL;
 	}
 
-	err = uc_mgr_get_substituted_value(uc_mgr, &s, mode);
-	if (err < 0)
-		return err;
+	if (uc_mgr->conf_format < 7) {
+		s = (char *)mode;
+	} else {
+		err = uc_mgr_get_substituted_value(uc_mgr, &s, mode);
+		if (err < 0)
+			return err;
+	}
 	if (strncasecmp(s, "exist", 5) == 0) {
 		amode = F_OK;
 	} else if (strcasecmp(s, "read") == 0) {
@@ -309,17 +313,23 @@ static int if_eval_path(snd_use_case_mgr_t *uc_mgr, snd_config_t *eval)
 		free(s);
 		return -EINVAL;
 	}
-	free(s);
+	if (s != mode)
+		free(s);
 
-	err = uc_mgr_get_substituted_value(uc_mgr, &s, path);
-	if (err < 0)
-		return err;
+	if (uc_mgr->conf_format < 7) {
+		s = (char *)path;
+	} else {
+		err = uc_mgr_get_substituted_value(uc_mgr, &s, path);
+		if (err < 0)
+			return err;
+	}
 #ifdef HAVE_EACCESS
 	err = eaccess(s, amode);
 #else
 	err = access(s, amode);
 #endif
-	free(s);
+	if (s != path)
+		free(s);
 	return err ? 0 : 1;
 }
 

src/ucm/ucm_confdoc.h

@@ -63,7 +63,7 @@ use case verbs for that sound card. i.e.:
 # Example master file for blah sound card
 # By Joe Blogs <joe@bloggs.org>
 
-Syntax 6
+Syntax 7
 
 # Use Case name for user interface
 Comment "Nice Abstracted Soundcard"
@@ -489,7 +489,8 @@ DefineMacro.macro1 {
 The arguments in the macro are refered as the variables with the double
 underscore name prefix (like *__variable*). The configuration block in
 the DefineMacro subtree is always evaluated (including arguments and variables)
-at the time of the instantiation.
+at the time of the instantiation. Argument string substitutions
+(for multiple macro call levels) were added in *Syntax* version *7*.
 
 The macros can be instantiated (expanded) using:
 
@@ -563,6 +564,15 @@ Field                | Description
 String               | string
 Regex                | regex expression (extended posix, ignore case)
 
+#### Path is present (Type Path)
+
+Field                | Description
+---------------------|-----------------------
+Path                 | path (filename)
+Mode                 | exist,read,write,exec
+
+Note: Substitution for Path and Mode fields were added in *Syntax* version *7*.
+
 #### ALSA control element exists (Type ControlExists)
 
 Field                | Description

src/ucm/ucm_local.h

@@ -40,7 +40,7 @@
 #include <pthread.h>
 #include "use-case.h"
 
-#define SYNTAX_VERSION_MAX	6
+#define SYNTAX_VERSION_MAX	7
 
 #define MAX_CARD_SHORT_NAME	32
 #define MAX_CARD_LONG_NAME	80