1. Prevent the addition of an extra '/' to the beginning of an absolute pathname.

2. If ast_monitor_change_fname is called and the new filename is the same as the old, then exit early and don't set the
   filename_changed field in the monitor structure. Setting it in this case was causing ast_monitor_stop to erroneously
   delete them.

(closes issue #11741)
Reported by: garlew
Tested by: putnopvut



git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@101531 65c4cc65-6c06-0410-ace0-fbb531ad65f3

res/res_monitor.c

@@ -47,6 +47,7 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 #include "asterisk/app.h"
 #include "asterisk/utils.h"
 #include "asterisk/config.h"
+#include "asterisk/options.h"
 
 AST_MUTEX_DEFINE_STATIC(monitorlock);
 
@@ -156,6 +157,7 @@ int ast_monitor_start(	struct ast_channel *chan, const char *format_spec,
 		/* Determine file names */
 		if (!ast_strlen_zero(fname_base)) {
 			int directory = strchr(fname_base, '/') ? 1 : 0;
+			const char *absolute = *fname_base == '/' ? "" : "/";
 			/* try creating the directory just in case it doesn't exist */
 			if (directory) {
 				char *name = strdup(fname_base);
@@ -163,10 +165,10 @@ int ast_monitor_start(	struct ast_channel *chan, const char *format_spec,
 				free(name);
 				ast_safe_system(tmp);
 			}
-			snprintf(monitor->read_filename, FILENAME_MAX, "%s/%s-in",
-						directory ? "" : ast_config_AST_MONITOR_DIR, fname_base);
-			snprintf(monitor->write_filename, FILENAME_MAX, "%s/%s-out",
-						directory ? "" : ast_config_AST_MONITOR_DIR, fname_base);
+			snprintf(monitor->read_filename, FILENAME_MAX, "%s%s%s-in",
+						directory ? "" : ast_config_AST_MONITOR_DIR, absolute, fname_base);
+			snprintf(monitor->write_filename, FILENAME_MAX, "%s%s%s-out",
+						directory ? "" : ast_config_AST_MONITOR_DIR, absolute, fname_base);
 			ast_copy_string(monitor->filename_base, fname_base, sizeof(monitor->filename_base));
 		} else {
 			ast_mutex_lock(&monitorlock);
@@ -300,6 +302,7 @@ int ast_monitor_stop(struct ast_channel *chan, int need_lock)
 			int directory = strchr(name, '/') ? 1 : 0;
 			char *dir = directory ? "" : ast_config_AST_MONITOR_DIR;
 			const char *execute, *execute_args;
+			const char *absolute = *name == '/' ? "" : "/";
 
 			/* Set the execute application */
 			execute = pbx_builtin_getvar_helper(chan, "MONITOR_EXEC");
@@ -317,9 +320,9 @@ int ast_monitor_stop(struct ast_channel *chan, int need_lock)
 				execute_args = "";
 			}
 			
-			snprintf(tmp, sizeof(tmp), "%s \"%s/%s-in.%s\" \"%s/%s-out.%s\" \"%s/%s.%s\" %s &", execute, dir, name, format, dir, name, format, dir, name, format,execute_args);
+			snprintf(tmp, sizeof(tmp), "%s \"%s%s%s-in.%s\" \"%s%s%s-out.%s\" \"%s%s%s.%s\" %s &", execute, dir, absolute, name, format, dir, absolute, name, format, dir, absolute, name, format,execute_args);
 			if (delfiles) {
-				snprintf(tmp2,sizeof(tmp2), "( %s& rm -f \"%s/%s-\"* ) &",tmp, dir ,name); /* remove legs when done mixing */
+				snprintf(tmp2,sizeof(tmp2), "( %s& rm -f \"%s%s%s-\"* ) &",tmp, dir, absolute, name); /* remove legs when done mixing */
 				ast_copy_string(tmp, tmp2, sizeof(tmp));
 			}
 			ast_log(LOG_DEBUG,"monitor executing %s\n",tmp);
@@ -373,6 +376,18 @@ int ast_monitor_change_fname(struct ast_channel *chan, const char *fname_base, i
 
 	if (chan->monitor) {
 		int directory = strchr(fname_base, '/') ? 1 : 0;
+		const char *absolute = *fname_base == '/' ? "" : "/";
+		char tmpstring[sizeof(chan->monitor->filename_base)] = "";
+
+		/* before continuing, see if we're trying to rename the file to itself... */
+		snprintf(tmpstring, sizeof(tmpstring), "%s%s%s", directory ? "" : ast_config_AST_MONITOR_DIR, absolute, fname_base);
+		if (!strcmp(tmpstring, chan->monitor->filename_base)) {
+			if (option_debug > 2)
+				ast_log(LOG_DEBUG, "No need to rename monitor filename to itself\n");
+			UNLOCK_IF_NEEDED(chan, need_lock);
+			return 0;
+		}
+
 		/* try creating the directory just in case it doesn't exist */
 		if (directory) {
 			char *name = strdup(fname_base);
@@ -381,7 +396,7 @@ int ast_monitor_change_fname(struct ast_channel *chan, const char *fname_base, i
 			ast_safe_system(tmp);
 		}
 
-		snprintf(chan->monitor->filename_base, FILENAME_MAX, "%s/%s", directory ? "" : ast_config_AST_MONITOR_DIR, fname_base);
+		ast_copy_string(chan->monitor->filename_base, tmpstring, sizeof(chan->monitor->filename_base));
 		chan->monitor->filename_changed = 1;
 	} else {
 		ast_log(LOG_WARNING, "Cannot change monitor filename of channel %s to %s, monitoring not started\n", chan->name, fname_base);