Implement severity suppression in log streams; other minor fixes.

* include/mailutils/stream.h (MU_LOGSTREAM_ADVANCE_LOCUS_LINE)
(MU_LOGSTREAM_ADVANCE_LOCUS_COL): Rename to MU_IOCTL_.*.  All
uses updated.
(MU_IOCTL_LOGSTREAM_SUPPRESS_SEVERITY)
(MU_IOCTL_LOGSTREAM_SUPPRESS_SEVERITY_NAME): New ioctls.
* include/mailutils/sys/logstream.h (_mu_log_stream)<threshold>: New
member.
* include/mailutils/syslog.h (mu_log_severity_threshold): New extern.
* libmailutils/cfg/parser.y (_cfg_default_printer): Remove leftover
static function.
* libmailutils/stream/logstream.c (mu_severity_from_string)
(mu_severity_to_string): New functions.
(_log_write): Fix double free.
Implement severity suppression.
(_log_ioctl): Handle MU_IOCTL_LOGSTREAM_SUPPRESS_SEVERITY.
* libmu_cfg/common.c (mu_logging_param): New parameter
"severity".

@@ -111,12 +111,22 @@ enum mu_buffer_type
      Arg: NULL (increment by 1)
           int *
   */
-#define MU_LOGSTREAM_ADVANCE_LOCUS_LINE 24
+#define MU_IOCTL_LOGSTREAM_ADVANCE_LOCUS_LINE 24
   /* Advance locus column.
      Arg: NULL (increment by 1)
           int *
   */
-#define MU_LOGSTREAM_ADVANCE_LOCUS_COL  25
+#define MU_IOCTL_LOGSTREAM_ADVANCE_LOCUS_COL  25
+
+  /* Suppress output of messages having severity lower than the
+     given threshold.
+     Arg: int *
+  */
+#define MU_IOCTL_LOGSTREAM_SUPPRESS_SEVERITY  26
+  /* Same as above, but:
+     Arg: const char *
+  */
+#define MU_IOCTL_LOGSTREAM_SUPPRESS_SEVERITY_NAME 27
   
 #define MU_TRANSPORT_INPUT  0
 #define MU_TRANSPORT_OUTPUT 1

@@ -22,11 +22,13 @@
 
 struct _mu_log_stream
 {
-  struct _mu_stream base;
-  mu_stream_t transport;
-  unsigned severity;
-  int logmode;
-  struct mu_locus locus;
+  struct _mu_stream base;  /* Base stream */
+  mu_stream_t transport;   /* Transport stream */
+  unsigned severity;       /* Default severity */
+  unsigned threshold;      /* Suppress the output of severities below 
+			      this threshold */
+  int logmode;             /* Mode flags */
+  struct mu_locus locus;   /* Location */
 };
 
 #endif

@@ -28,6 +28,8 @@ extern int mu_log_syslog;
 extern int mu_log_facility;
 extern char *mu_log_tag;
 extern int mu_log_print_severity;
+extern unsigned mu_log_severity_threshold;
+
 #define MU_LOG_TAG() (mu_log_tag ? mu_log_tag : mu_program_name)
   
 int mu_string_to_syslog_facility (const char *str, int *pfacility);

@@ -379,13 +379,6 @@ opt_sc  : /* empty */
 
 %%
 
-static int
-_cfg_default_printer (void *unused, mu_log_level_t level, const char *str)
-{
-  fprintf (stderr, "%s", str);
-  return 0;
-}
-
 void
 mu_cfg_set_debug ()
 {

@@ -132,3 +132,4 @@ int mu_log_syslog = 0;
 int mu_log_facility = LOG_FACILITY;
 char *mu_log_tag = NULL;
 int mu_log_print_severity = 0;
+unsigned mu_log_severity_threshold = MU_LOG_DEBUG;

@@ -119,6 +119,9 @@ mu_stdstream_strerr_setup (int type)
 	  int mode = MU_LOGMODE_SEVERITY;
 	  mu_stream_ioctl (str, MU_IOCTL_LOGSTREAM_SET_MODE, &mode);
 	}
+      if (mu_log_severity_threshold > MU_LOG_DEBUG)
+	mu_stream_ioctl (str, MU_IOCTL_LOGSTREAM_SUPPRESS_SEVERITY,
+			 &mu_log_severity_threshold);
       mu_stream_destroy (&mu_strerr);
       mu_strerr = str;
     }

@@ -24,6 +24,7 @@
 #include <mailutils/types.h>
 #include <mailutils/errno.h>
 #include <mailutils/cctype.h>
+#include <mailutils/cstr.h>
 #include <mailutils/log.h>
 
 #include <mailutils/nls.h>
@@ -42,6 +43,31 @@ char *_mu_severity_str[] = {
 };
 int _mu_severity_num = MU_ARRAY_SIZE (_mu_severity_str);
 
+int
+mu_severity_from_string (const char *str, unsigned *pn)
+{
+  int i;
+
+  for (i = 0; i < _mu_severity_num; i++)
+    {
+      if (mu_c_strcasecmp (_mu_severity_str[i], str) == 0)
+	{
+	  *pn = i;
+	  return 0;
+	}
+    }
+  return MU_ERR_NOENT;
+}
+
+int
+mu_severity_to_string (unsigned n, const char **pstr)
+{
+  if (n >= _mu_severity_num)
+    return MU_ERR_NOENT;
+  *pstr = _mu_severity_str[n];
+  return 0;
+}
+
 static int
 _locus_set_file (struct mu_locus *loc, const char *file, size_t len)
 {
@@ -167,13 +193,30 @@ _log_write (struct _mu_stream *str, const char *buf, size_t size,
   if (severity >= _mu_severity_num)
     severity = MU_LOG_EMERG;
 
+  if (fname)
+    {
+      loc.mu_file = NULL;
+      _locus_set_file (&loc, fname, flen);
+    }
+  
+  if (save_locus)
+    {
+      _locus_set_file (&sp->locus, loc.mu_file, strlen (loc.mu_file));
+      _locus_set_line (&sp->locus, loc.mu_line);
+      _locus_set_col (&sp->locus, loc.mu_col);
+    }
+  
+  if (severity < sp->threshold)
+    {
+      if (fname)
+	free (loc.mu_file);
+      return 0;
+    }
+  
   mu_stream_ioctl (sp->transport, MU_IOCTL_LOGSTREAM_SET_SEVERITY, &severity);
   
   if (logmode & MU_LOGMODE_LOCUS)
     {
-      if (fname)
-	_locus_set_file (&loc, fname, flen);
-
       if (loc.mu_file)
 	{
 	  mu_stream_write (sp->transport, loc.mu_file,
@@ -188,13 +231,6 @@ _log_write (struct _mu_stream *str, const char *buf, size_t size,
 	}
     }
 
-  if (save_locus)
-    {
-      _locus_set_file (&sp->locus, loc.mu_file, strlen (loc.mu_file));
-      _locus_set_line (&sp->locus, loc.mu_line);
-      _locus_set_col (&sp->locus, loc.mu_col);
-    }
-  
   if (fname)
     free (loc.mu_file);
   
@@ -332,20 +368,35 @@ _log_ctl (struct _mu_stream *str, int op, void *arg)
 	break;
       }
 
-    case MU_LOGSTREAM_ADVANCE_LOCUS_LINE:
+    case MU_IOCTL_LOGSTREAM_ADVANCE_LOCUS_LINE:
       if (!arg)
 	sp->locus.mu_line++;
       else
 	sp->locus.mu_line += *(int*)arg;
       break;
 
-    case MU_LOGSTREAM_ADVANCE_LOCUS_COL:
+    case MU_IOCTL_LOGSTREAM_ADVANCE_LOCUS_COL:
       if (!arg)
 	sp->locus.mu_col++;
       else
 	sp->locus.mu_col += *(int*)arg;
       break;
+
+    case MU_IOCTL_LOGSTREAM_SUPPRESS_SEVERITY:
+      if (!arg)
+	sp->threshold = MU_LOG_DEBUG;
+      else if (*(unsigned*)arg >= _mu_severity_num)
+	return MU_ERR_NOENT;
+      sp->threshold = *(unsigned*)arg;
+      break;
 	
+    case MU_IOCTL_LOGSTREAM_SUPPRESS_SEVERITY_NAME:
+      if (!arg)
+	sp->threshold = MU_LOG_DEBUG;
+      else
+	return mu_severity_from_string ((const char *) arg, &sp->threshold);
+      break;
+      
     default:
       return ENOSYS;
     }

@@ -143,11 +143,30 @@ cb_facility (void *data, mu_config_value_t *val)
    return 0;
 }
 
+static int
+cb_severity (void *data, mu_config_value_t *val)
+{
+  unsigned n;
+  
+  if (mu_cfg_assert_value_type (val, MU_CFG_STRING))
+    return 1;
+  if (mu_severity_from_string (val->v.string, &n))
+    {
+      mu_error (_("unknown severity `%s'"), val->v.string);
+      return 1;
+    }
+  mu_log_severity_threshold = n;
+  return 0;
+}      
+
 static struct mu_cfg_param mu_logging_param[] = {
   { "syslog", mu_cfg_bool, &mu_log_syslog, 0, NULL,
     N_("Send diagnostics to syslog.") },
   { "print-severity", mu_cfg_bool, &mu_log_print_severity, 0, NULL,
     N_("Print message severity levels.") },
+  { "severity", mu_cfg_callback, NULL, 0, cb_severity,
+    N_("Output only messages with a severity equal to or greater than "
+       "this one.") },
   { "facility", mu_cfg_callback, NULL, 0, cb_facility,
     N_("Set syslog facility. Arg is one of the following: user, daemon, "
        "auth, authpriv, mail, cron, local0 through local7 (case-insensitive), "

@@ -27,7 +27,7 @@ source_readline (void *closure, int cont MU_ARG_UNUSED)
   if (getline (&buf, &s, fp) >= 0)
     {
       mu_rtrim_class (buf, MU_CTYPE_SPACE);
-      mu_stream_ioctl (mu_strerr, MU_LOGSTREAM_ADVANCE_LOCUS_LINE, NULL);
+      mu_stream_ioctl (mu_strerr, MU_IOCTL_LOGSTREAM_ADVANCE_LOCUS_LINE, NULL);
       return buf;
     }