Support --quiet argument (suppresses info() messages).

Signed-off-by: Stefan Westerfeld <stefan@space.twc.de>

src/TODO

@@ -7,5 +7,4 @@ streaming:
 - mp3 indexing / detect (resync-limit)
 - final documentation
 - --snr
-- --quiet
 - ab init lazy

src/audiowmark.cc

@@ -41,6 +41,7 @@ print_usage()
   printf ("  --strength <s>        set watermark strength              [%.6g]\n", Params::water_delta * 1000);
   printf ("  --linear              disable non-linear bit storage\n");
   printf ("  --key <file>          load watermarking key from file\n");
+  printf ("  -q, --quiet           disable information messages\n");
 }
 
 static bool
@@ -260,6 +261,11 @@ parse_options (int   *argc_p,
           Params::raw_input_format.set_sample_rate (r);
           Params::raw_output_format.set_sample_rate (r);
         }
+      else if (check_arg (argc, argv, &i, "--quiet")
+            || check_arg (argc, argv, &i, "-q"))
+        {
+          set_log_level (Log::WARNING);
+        }
     }
 
   /* resort argc/argv */

src/utils.cc

@@ -91,18 +91,27 @@ vec_to_hex_str (const vector<unsigned char>& vec)
   return s;
 }
 
-enum class Log { ERROR, WARNING, INFO, DEBUG };
+static Log log_level = Log::INFO;
+
+void
+set_log_level (Log level)
+{
+  log_level = level;
+}
 
 static void
 logv (Log log, const char *format, va_list vargs)
 {
-  char buffer[1024];
+  if (log >= log_level)
+    {
+      char buffer[1024];
 
-  vsnprintf (buffer, sizeof (buffer), format, vargs);
+      vsnprintf (buffer, sizeof (buffer), format, vargs);
 
-  /* could support custom log function here */
-  fprintf (stderr, "%s", buffer);
-  fflush (stderr);
+      /* could support custom log function here */
+      fprintf (stderr, "%s", buffer);
+      fflush (stderr);
+    }
 }
 
 void

src/utils.hh

@@ -37,6 +37,10 @@ void warning (const char *format, ...) AUDIOWMARK_PRINTF (1, 2);
 void info (const char *format, ...) AUDIOWMARK_PRINTF (1, 2);
 void debug (const char *format, ...) AUDIOWMARK_PRINTF (1, 2);
 
+enum class Log { ERROR = 3, WARNING = 2, INFO = 1, DEBUG = 0 };
+
+void set_log_level (Log level);
+
 class Error
 {
 public: