From 7dbc0211496dd6e217507293a2579811c7b385c5 Mon Sep 17 00:00:00 2001
From: Markus Makela <markus.makela@mariadb.com>
Date: Wed, 20 May 2015 16:16:49 +0300
Subject: [PATCH] Added more logging when a monitor script cannot be executed.

---
 server/core/externcmd.c                 | 19 ++++++++++++++++++-
 server/modules/monitor/galeramon.c      | 12 +++++++++++-
 server/modules/monitor/mmmon.c          | 13 +++++++++++--
 server/modules/monitor/monitor_common.c |  6 +++++-
 server/modules/monitor/mysql_mon.c      | 12 +++++++++++-
 server/modules/monitor/ndbclustermon.c  | 12 +++++++++++-
 6 files changed, 67 insertions(+), 7 deletions(-)

diff --git a/server/core/externcmd.c b/server/core/externcmd.c
index cc7989fc6..93579faef 100644
--- a/server/core/externcmd.c
+++ b/server/core/externcmd.c
@@ -97,6 +97,23 @@ EXTERNCMD* externcmd_allocate(char* argstr)
 	    free(cmd);
 	    return NULL;
 	}
+	if(access(cmd->parameters[0],F_OK) != 0)
+	{
+	    skygw_log_write(LE,
+		     "Error: Cannot find file: %s",
+		     cmd->parameters[0]);
+	    externcmd_free(cmd);
+	    return NULL;
+	}
+
+	if(access(cmd->parameters[0],X_OK) != 0)
+	{
+	    skygw_log_write(LE,
+		     "Error: Cannot execute file: %s",
+		     cmd->parameters[0]);
+	    externcmd_free(cmd);
+	    return NULL;
+	}
     }
     return cmd;
 }
@@ -138,7 +155,7 @@ int externcmd_execute(EXTERNCMD* cmd)
     {
         /** Child process, execute command */
         execvp(cmd->parameters[0],cmd->parameters);
-	exit(1);
+	_exit(1);
     }
     else
     {
diff --git a/server/modules/monitor/galeramon.c b/server/modules/monitor/galeramon.c
index a46df8f77..404448d82 100644
--- a/server/modules/monitor/galeramon.c
+++ b/server/modules/monitor/galeramon.c
@@ -156,7 +156,17 @@ startMonitor(void *arg,void* opt)
 	{
 	    if(handle->script)
 		free(handle->script);
-	    handle->script = strdup(params->value);
+	    if(access(params->value,X_OK) == 0)
+	    {
+		handle->script = strdup(params->value);
+	    }
+	    else
+	    {
+		skygw_log_write(LE,
+			 "Error: The file cannot be executed: %s",
+			 params->value);
+		handle->script = NULL;
+	    }
 	}
 	else if(!strcmp(params->name,"events"))
 	{
diff --git a/server/modules/monitor/mmmon.c b/server/modules/monitor/mmmon.c
index bd1c6bb85..4ca8d6048 100644
--- a/server/modules/monitor/mmmon.c
+++ b/server/modules/monitor/mmmon.c
@@ -142,8 +142,17 @@ startMonitor(void *arg,void* opt)
 	    {
 		free(handle->script);
 	    }
-
-	    handle->script = strdup(params->value);
+	    if(access(params->value,X_OK) == 0)
+	    {
+		handle->script = strdup(params->value);
+	    }
+	    else
+	    {
+		skygw_log_write(LE,
+			 "Error: The file cannot be executed: %s",
+			 params->value);
+		handle->script = NULL;
+	    }
 	}
 	else if(!strcmp(params->name,"events"))
 	{
diff --git a/server/modules/monitor/monitor_common.c b/server/modules/monitor/monitor_common.c
index 6f9be583b..fb59eadbd 100644
--- a/server/modules/monitor/monitor_common.c
+++ b/server/modules/monitor/monitor_common.c
@@ -303,7 +303,11 @@ void monitor_launch_script(MONITOR* mon,MONITOR_SERVERS* ptr, char* script)
 	     ptr->server->unique_name);
 
     mon_append_node_names(mon->databases,argstr,PATH_MAX + MON_ARG_MAX + 1);
-    cmd = externcmd_allocate(argstr);
+    if((cmd = externcmd_allocate(argstr)) == NULL)
+    {
+	skygw_log_write(LE,"Failed to execute script: %s",script);
+	return;
+    }
 
     if(externcmd_execute(cmd))
     {
diff --git a/server/modules/monitor/mysql_mon.c b/server/modules/monitor/mysql_mon.c
index 75f7027c4..1e7fde4e6 100644
--- a/server/modules/monitor/mysql_mon.c
+++ b/server/modules/monitor/mysql_mon.c
@@ -170,7 +170,17 @@ startMonitor(void *arg, void* opt)
 	{
 	    if(handle->script)
 		free(handle->script);
-	    handle->script = strdup(params->value);
+	    if(access(params->value,X_OK) == 0)
+	    {
+		handle->script = strdup(params->value);
+	    }
+	    else
+	    {
+		skygw_log_write(LE,
+			 "Error: The file cannot be executed: %s",
+			 params->value);
+		handle->script = NULL;
+	    }
 	}
 	else if(!strcmp(params->name,"events"))
 	{
diff --git a/server/modules/monitor/ndbclustermon.c b/server/modules/monitor/ndbclustermon.c
index 88444aaaf..4488786af 100644
--- a/server/modules/monitor/ndbclustermon.c
+++ b/server/modules/monitor/ndbclustermon.c
@@ -132,7 +132,17 @@ startMonitor(void *arg,void* opt)
 	{
 	    if(handle->script)
 		free(handle->script);
-	    handle->script = strdup(params->value);
+	    if(access(params->value,X_OK) == 0)
+	    {
+		handle->script = strdup(params->value);
+	    }
+	    else
+	    {
+		skygw_log_write(LE,
+			 "Error: The file cannot be executed: %s",
+			 params->value);
+		handle->script = NULL;
+	    }
 	}
 	else if(!strcmp(params->name,"events"))
 	{