log: implement filter based on string configuration (env LIBASOUND_DEBUG).

Examples:

 "debug"                 - Set global level to debug
 "3"                     - Set global level to 3 (info)
 "info,pcm:debug"        - Set global to info, pcm to debug
 "error,mixer:5,pcm:4"   - Set global to error, mixer to 5 (trace), pcm to 4 (debug)

Signed-off-by: Jaroslav Kysela <perex@perex.cz>

diff --git a/include/error.h b/include/error.h
index 7e4ab6a7aa59240d9775369c0de70fe3de01fbf8..13a9d2bc73dac09eccca2944eb089659f7a3047a 100644 (file)
--- a/include/error.h
+++ b/include/error.h
@@ -86,6 +86,7 @@ const char *snd_strerror(int errnum);
  */
 typedef void (*snd_lib_log_handler_t)(int prio, int interface, const char *file, int line, const char *function, int errcode, const char *fmt, va_list arg);
 extern snd_lib_log_handler_t snd_lib_vlog;
+int snd_lib_log_filter(int prio, int interface, const char *configstr);
 void snd_lib_log(int prio, int interface, const char *file, int line, const char *function, int errcode, const char *fmt, ...) /* __attribute__ ((format (printf, 7, 8))) */;
 void snd_lib_check(int interface, const char *file, int line, const char *function, int errcode, const char *fmt, ...);
 snd_lib_log_handler_t snd_lib_log_set_handler(snd_lib_log_handler_t handler);

diff --git a/src/Versions.in.in b/src/Versions.in.in
index 36b6ab5d7b320e2e2ba563bc7262609cfe0a1bb0..18f31f9d3016e399871b52e07f3303747b166466 100644 (file)
--- a/src/Versions.in.in
+++ b/src/Versions.in.in
@@ -225,5 +225,6 @@ ALSA_1.2.15 {
     @SYMBOL_PREFIX@snd_lib_log_set_local;
     @SYMBOL_PREFIX@snd_lib_log_priority;
     @SYMBOL_PREFIX@snd_lib_log_interface;
+    @SYMBOL_PREFIX@snd_lib_log_filter;
     @SYMBOL_PREFIX@snd_lib_check;
 } ALSA_1.2.13;

diff --git a/src/error.c b/src/error.c
index 56ff27c78688449eb30c1dddd0f97415c0626971..d8b5bb6a2e281543b532d937a9c2c801c1630912 100644 (file)
--- a/src/error.c
+++ b/src/error.c
@@ -138,6 +138,158 @@ const char *snd_lib_log_interface(int interface)
        return NULL;
 }
 
+/**
+ * \brief Structure to hold parsed debug configuration.
+ */
+static struct {
+       const char *configstr;
+       int global_level;
+       int interface_levels[SND_ILOG_LAST + 1];
+       int parsed;
+} debug_config;
+
+/**
+ * \brief Parse the LIBASOUND_DEBUG environment variable.
+ *
+ * Format: [<level>][,<interface1>:<level1>][,<interface2>:<level2>,...]
+ *
+ * Examples:
+ *   "debug"                 - Set global level to debug
+ *   "3"                     - Set global level to 3 (info)
+ *   "info,pcm:debug"        - Set global to info, pcm to debug
+ *   "error,mixer:5,pcm:4"   - Set global to error, mixer to 5 (trace), pcm to 4 (debug)
+ */
+static void parse_libasound_debug(const char *configstr)
+{
+       const char *env;
+       char *str, *token, *saveptr;
+       int i;
+
+       if (debug_config.parsed && debug_config.configstr == configstr)
+               return;
+
+       debug_config.parsed = 1;
+       debug_config.global_level = 0;
+       debug_config.configstr = configstr;
+       for (i = 0; i <= SND_ILOG_LAST; i++)
+               debug_config.interface_levels[i] = 0;
+
+       if (configstr == NULL) {
+               env = getenv("LIBASOUND_DEBUG");
+               if (!env || !*env)
+                       return;
+       } else {
+               env = configstr;
+       }
+
+       str = strdup(env);
+       if (!str)
+               return;
+
+       token = strtok_r(str, ",", &saveptr);
+       while (token) {
+               char *colon = strchr(token, ':');
+               if (colon) {
+                       /* interface:level format */
+                       *colon = '\0';
+                       const char *interface_name = token;
+                       const char *level_str = colon + 1;
+                       int interface_num = -1;
+                       int level = -1;
+
+                       /* Try to find interface by name */
+                       for (i = 1; i <= SND_ILOG_LAST; i++) {
+                               if (snd_ilog_interface_names[i] &&
+                                   strcmp(snd_ilog_interface_names[i], interface_name) == 0) {
+                                       interface_num = i;
+                                       break;
+                               }
+                       }
+
+                       /* If not found by name, try direct number */
+                       if (interface_num < 0) {
+                               char *endptr;
+                               long val = strtol(interface_name, &endptr, 10);
+                               if (*endptr == '\0' && val >= 0 && val <= SND_ILOG_LAST)
+                                       interface_num = val;
+                       }
+
+                       /* Parse level */
+                       for (i = 1; i <= SND_LOG_LAST; i++) {
+                               if (snd_log_prio_names[i] &&
+                                   strcmp(snd_log_prio_names[i], level_str) == 0) {
+                                       level = i;
+                                       break;
+                               }
+                       }
+
+                       /* If not found by name, try direct number */
+                       if (level < 0) {
+                               char *endptr;
+                               long val = strtol(level_str, &endptr, 10);
+                               if (*endptr == '\0' && val >= 0 && val <= SND_LOG_LAST)
+                                       level = val;
+                       }
+
+                       /* Store the interface-specific level */
+                       if (interface_num > 0 && level > 0)
+                               debug_config.interface_levels[interface_num] = level;
+               } else {
+                       /* Global level only */
+                       int level = -1;
+
+                       /* Try to find level by name */
+                       for (i = 1; i <= SND_LOG_LAST; i++) {
+                               if (snd_log_prio_names[i] &&
+                                   strcmp(snd_log_prio_names[i], token) == 0) {
+                                       level = i;
+                                       break;
+                               }
+                       }
+
+                       /* If not found by name, try direct number */
+                       if (level < 0) {
+                               char *endptr;
+                               long val = strtol(token, &endptr, 10);
+                               if (*endptr == '\0' && val >= 0 && val <= SND_LOG_LAST)
+                                       level = val;
+                       }
+
+                       if (level > 0)
+                               debug_config.global_level = level;
+               }
+
+               token = strtok_r(NULL, ",", &saveptr);
+       }
+
+       free(str);
+}
+
+/**
+ * \brief Check if a log message should be shown based on LIBASOUND_DEBUG.
+ * \param prio Priority value (SND_LOG_*).
+ * \param interface Interface (SND_ILOG_*).
+ * \param configstr Configuration string (usually LIBASOUND_DEBUG environment variable)
+ * \return 1 if the message should be shown, 0 otherwise.
+ */
+int snd_lib_log_filter(int prio, int interface, const char *configstr)
+{
+       unsigned int level;
+
+       parse_libasound_debug(configstr);
+
+       if (interface > 0 && interface <= SND_ILOG_LAST && debug_config.interface_levels[interface] > 0) {
+               level = debug_config.interface_levels[interface];
+       } else {
+               level = debug_config.global_level;      }
+
+       if (level == 0)
+               level = SND_LOG_ERROR;
+
+       /* Show message if its priority is less than or equal to the configured level */
+       return prio <= (int)level;
+}
+
 /**
  * \brief The default log handler function.
  * \param prio Priority value (SND_LOG_*).
@@ -165,6 +317,10 @@ static void snd_lib_vlog_default(int prio, int interface, const char *file, int
                local_error(file, line, function, errcode, fmt, arg);
                return;
        }
+
+       if (!snd_lib_log_filter(prio, interface, NULL))
+               return;
+
        fprintf(stderr, "ALSA lib %s:%i:(%s) ", file, line, function);
 
        text = snd_lib_log_priority(prio);