Patch from David Gibson <dgibson@linuxcare.com> to reduce "silent abort"

problems with smbd failing to create a log file. If we can't create a log
file keep using the old file.
Jeremy.
(This used to be commit c4e6aa1322fa7bc59708163c42eef6ccbd6c2305)

diff --git a/source3/include/proto.h b/source3/include/proto.h
index e2d31fa19afe4e1228abb03ac0fba736e85128fd..1b529f6b02ed81aeb1724236143b807bc2c44258 100644 (file)
--- a/source3/include/proto.h
+++ b/source3/include/proto.h
@@ -82,7 +82,7 @@ BOOL debug_parse_levels(char *params_str);
 void debug_message(int msg_type, pid_t src, void *buf, size_t len);
 void debug_message_send(pid_t pid, int level);
 void setup_logging(char *pname, BOOL interactive);
-void reopen_logs( void );
+BOOL reopen_logs( void );
 void force_check_log_size( void );
 BOOL need_to_check_log_size( void );
 void check_log_size( void );

diff --git a/source3/lib/debug.c b/source3/lib/debug.c
index 27fa80ca3f82a5a3ad34e34a5299238d49e4a06a..9c97385db332517dc735f4b52258473a3612a81d 100644 (file)
--- a/source3/lib/debug.c
+++ b/source3/lib/debug.c
@@ -82,6 +82,7 @@
 FILE   *dbf        = NULL;
 pstring debugf     = "";
 BOOL    append_log = False;
+
 int     DEBUGLEVEL_CLASS[DBGC_LAST];
 int     DEBUGLEVEL = DEBUGLEVEL_CLASS;
 
@@ -105,6 +106,12 @@ int     DEBUGLEVEL = DEBUGLEVEL_CLASS;
  *                    to build the formatted output.
  *
  *  format_pos      - Marks the first free byte of the format_bufr.
+ * 
+ *
+ *  log_overflow    - When this variable is True, never attempt to check the
+ *                    size of the log. This is a hack, so that we can write
+ *                    a message using DEBUG, from open_logs() when we
+ *                    are unable to open a new log file for some reason.
  */
 
 static BOOL    stdout_logging = False;
@@ -114,6 +121,7 @@ static int     syslog_level   = 0;
 #endif
 static pstring format_bufr    = { '\0' };
 static size_t     format_pos     = 0;
+static BOOL    log_overflow   = False;
 
 /*
 * Define all the debug class selection names here. Names *MUST NOT* contain 
@@ -289,19 +297,25 @@ void setup_logging(char *pname, BOOL interactive)
 /* ************************************************************************** **
  * reopen the log files
  * note that we now do this unconditionally
+ * We attempt to open the new debug fp before closing the old. This means
+ * if we run out of fd's we just keep using the old fd rather than aborting.
+ * Fix from dgibson@linuxcare.com.
  * ************************************************************************** **
  */
-void reopen_logs( void )
+
+BOOL reopen_logs( void )
 {
        pstring fname;
        mode_t oldumask;
+       FILE *new_dbf = NULL;
+       BOOL ret = True;
 
        if (DEBUGLEVEL_CLASS[ DBGC_ALL ] <= 0) {
                if (dbf) {
                        (void)fclose(dbf);
                        dbf = NULL;
                }
-               return;
+               return True;
        }
 
        oldumask = umask( 022 );
@@ -311,22 +325,33 @@ void reopen_logs( void )
                pstrcpy(fname, lp_logfile());
 
        pstrcpy( debugf, fname );
-       if (dbf)
-               (void)fclose(dbf);
        if (append_log)
-               dbf = sys_fopen( debugf, "a" );
+               new_dbf = sys_fopen( debugf, "a" );
        else
-               dbf = sys_fopen( debugf, "w" );
+               new_dbf = sys_fopen( debugf, "w" );
+
+       if (!new_dbf) {
+               log_overflow = True;
+               DEBUG(0, ("Unable to open new log file %s: %s\n", debugf, strerror(errno)));
+               log_overflow = False;
+               fflush(dbf);
+               ret = False;
+       } else {
+               setbuf(new_dbf, NULL);
+               if (dbf)
+                       (void) fclose(dbf);
+               dbf = new_dbf;
+       }
+
        /* Fix from klausr@ITAP.Physik.Uni-Stuttgart.De
         * to fix problem where smbd's that generate less
         * than 100 messages keep growing the log.
         */
        force_check_log_size();
-       if (dbf)
-               setbuf( dbf, NULL );
        (void)umask(oldumask);
-}
 
+       return ret;
+}
 
 /* ************************************************************************** **
  * Force a check of the log size.
@@ -363,54 +388,61 @@ BOOL need_to_check_log_size( void )
 
 void check_log_size( void )
 {
-  int         maxlog;
-  SMB_STRUCT_STAT st;
+       int         maxlog;
+       SMB_STRUCT_STAT st;
 
-  /*
-   *  We need to be root to check/change log-file, skip this and let the main
-   *  loop check do a new check as root.
-   */
+       /*
+        *  We need to be root to check/change log-file, skip this and let the main
+        *  loop check do a new check as root.
+        */
 
-  if( geteuid() != 0 )
-    return;
+       if( geteuid() != 0 )
+               return;
 
-  if( !need_to_check_log_size() )
-    return;
+       if(log_overflow || !need_to_check_log_size() )
+               return;
 
-  maxlog = lp_max_log_size() * 1024;
+       maxlog = lp_max_log_size() * 1024;
 
-  if( sys_fstat( fileno( dbf ), &st ) == 0 && st.st_size > maxlog )
-    {
-    (void)fclose( dbf );
-    dbf = NULL;
-    reopen_logs();
-    if( dbf && get_file_size( debugf ) > maxlog )
-      {
-      pstring name;
+       if( sys_fstat( fileno( dbf ), &st ) == 0 && st.st_size > maxlog ) {
+               (void)reopen_logs();
+               if( dbf && get_file_size( debugf ) > maxlog ) {
+                       pstring name;
 
-      (void)fclose( dbf );
-      dbf = NULL;
-      slprintf( name, sizeof(name)-1, "%s.old", debugf );
-      (void)rename( debugf, name );
-      reopen_logs();
-      }
-    }
-  /*
-   * Here's where we need to panic if dbf == NULL..
-   */
-  if(dbf == NULL) {
-    dbf = sys_fopen( "/dev/console", "w" );
-    if(dbf) {
-      DEBUG(0,("check_log_size: open of debug file %s failed - using console.\n",
-            debugf ));
-    } else {
-      /*
-       * We cannot continue without a debug file handle.
-       */
-      abort();
-    }
-  }
-  debug_count = 0;
+                       slprintf( name, sizeof(name)-1, "%s.old", debugf );
+                       (void)rename( debugf, name );
+      
+                       if (!reopen_logs()) {
+                               /* We failed to reopen a log - continue using the old name. */
+                               (void)rename(name, debugf);
+                       }
+               }
+       }
+
+       /*
+        * Here's where we need to panic if dbf == NULL..
+        */
+
+       if(dbf == NULL) {
+               /* This code should only be reached in very strange
+                       circumstances. If we merely fail to open the new log we
+                       should stick with the old one. ergo this should only be
+                       reached when opening the logs for the first time: at
+                       startup or when the log level is increased from zero.
+                       -dwg 6 June 2000
+               */
+               dbf = sys_fopen( "/dev/console", "w" );
+               if(dbf) {
+                       DEBUG(0,("check_log_size: open of debug file %s failed - using console.\n",
+                                       debugf ));
+               } else {
+                       /*
+                        * We cannot continue without a debug file handle.
+                        */
+                       abort();
+               }
+       }
+       debug_count = 0;
 } /* check_log_size */
 
 /* ************************************************************************** **