Add command line and config file option log-level

Signed-off-by: Yuxuan Shui <yshuiv7@gmail.com>

man/compton.1.asciidoc

@@ -76,6 +76,9 @@ OPTIONS
 *-S*::
 	Enable synchronous X operation (for debugging).
 
+*--log-level*::
+	Set the log level. Possible values are "TRACE", "DEBUG", "INFO", "WARN", "ERROR", in increasing level of importance. Case doesn't matter.
+
 *--show-all-xerrors*::
 	Show all X errors (for debugging).
 

src/compton.c

@@ -2607,6 +2607,7 @@ get_cfg(session_t *ps, int argc, char *const *argv, bool first_pass) {
     { "version", no_argument, NULL, 318 },
     { "no-x-selection", no_argument, NULL, 319 },
     { "no-name-pixmap", no_argument, NULL, 320 },
+    { "log-level", required_argument, NULL, 321 },
     { "reredir-on-root-change", no_argument, NULL, 731 },
     { "glx-reinit-on-root-change", no_argument, NULL, 732 },
     { "monitor-repaint", no_argument, NULL, 800 },
@@ -2895,6 +2896,15 @@ get_cfg(session_t *ps, int argc, char *const *argv, bool first_pass) {
           " removed in the future. If you really need this feature, please report\n"
           "an issue to let us know\n");
         break;
+      case 321: {
+        enum log_level tmp_level = string_to_log_level(optarg);
+        if (tmp_level == LOG_LEVEL_INVALID) {
+          log_warn("Invalid log level, defaults to WARN");
+        } else {
+          log_set_level_tls(tmp_level);
+        }
+        break;
+      }
       P_CASEBOOL(319, no_x_selection);
       P_CASEBOOL(731, reredir_on_root_change);
       P_CASEBOOL(732, glx_reinit_on_root_change);

src/config_libconfig.c

@@ -281,6 +281,15 @@ void parse_config_libconfig(session_t *ps, bool *shadow_enable,
   // --backend
   if (config_lookup_string(&cfg, "backend", &sval) && !parse_backend(ps, sval))
     exit(1);
+  // --log-level
+  if (config_lookup_string(&cfg, "log-level", &sval)) {
+    auto level = string_to_log_level(sval);
+    if (level == LOG_LEVEL_INVALID) {
+      log_warn("Invalid log level, defaults to WARN");
+    } else {
+      log_set_level_tls(level);
+    }
+  }
   // --sw-opti
   lcfg_lookup_bool(&cfg, "sw-opti", &ps->o.sw_opti);
   // --use-ewmh-active-win

src/log.c

@@ -54,7 +54,7 @@ static attr_const const char *log_level_to_string(enum log_level level) {
 	}
 }
 
-attr_const enum log_level string_to_log_level(const char *str) {
+enum log_level string_to_log_level(const char *str) {
 	if (strcasecmp(str, "TRACE") == 0)
 		return LOG_LEVEL_TRACE;
 	else if (strcasecmp(str, "DEBUG") == 0)

src/log.h

@@ -54,6 +54,7 @@ attr_malloc struct log *log_new(void);
 attr_nonnull_all void log_destroy(struct log *);
 attr_nonnull(1) void log_set_level(struct log *l, int level);
 attr_nonnull_all void log_add_target(struct log *, struct log_target *);
+attr_const enum log_level string_to_log_level(const char *);
 
 extern thread_local struct log *tls_logger;