gf_system: fork/exec instead of system

* most of the glusterd 'system()' are replaced with 'gf_system()'

Signed-off-by: Amar Tumballi <amar@gluster.com>
Signed-off-by: Anand V. Avati <avati@dev.gluster.com>

BUG: 1292 ()
URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=1292

2 files changed, 58 insertions, 0 deletions

diff --git a/libglusterfs/src/common-utils.c b/libglusterfs/src/common-utils.c
index 3b904f5224a..eef865ec500 100644
--- a/libglusterfs/src/common-utils.c
+++ b/libglusterfs/src/common-utils.c
@@ -36,6 +36,7 @@
 #include <time.h>
 #include <locale.h>
 #include <sys/socket.h>
+#include <sys/wait.h>
 #include <netinet/in.h>
 #include <arpa/inet.h>
 #include <signal.h>
@@ -1466,3 +1467,58 @@ get_checksum_for_file (int fd, uint32_t *checksum)
 
         return ret;
 }
+
+
+/* One should pass the command here with command with full path,
+   otherwise, execv will fail */
+int
+gf_system (const char *command)
+{
+        int    ret    = -1;
+        pid_t  pid    = 0;
+        int    status = 0;
+        int    idx    = 0;
+        char  *dupcmd = NULL;
+        char  *arg    = NULL;
+        char  *tmp    = NULL;
+        char  *argv[100] = { NULL, };
+
+        dupcmd = gf_strdup (command);
+        if (!dupcmd)
+                goto out;
+
+        pid = fork ();
+        if (pid < 0) {
+                /* failure */
+                goto out;
+        }
+        if (pid == 0) {
+                /* Child process */
+                /* Step 0: Prepare the argv */
+                arg = strtok_r (dupcmd, " ", &tmp);
+                while (arg) {
+                        argv[idx] = arg;
+                        arg = strtok_r (NULL, " ", &tmp);
+                        idx++;
+                }
+                /* Step 1: Close all 'fd' */
+                for (idx = 3; idx < 65536; idx++) {
+                        close (idx);
+                }
+                /* Step 2: execv (); */
+                ret = execvp (argv[0], argv);
+
+                /* Code will not come here at all */
+                gf_log ("", GF_LOG_ERROR, "execv of (%s) failed", command);
+        }
+        if (pid > 0) {
+                /* Current, ie, parent process */
+                pid = waitpid (pid, &status, 0);
+                ret = status;
+        }
+out:
+        if (dupcmd)
+                GF_FREE (dupcmd);
+
+        return ret;
+}
diff --git a/libglusterfs/src/common-utils.h b/libglusterfs/src/common-utils.h
index ab230993a5c..93d62f6cbc3 100644
--- a/libglusterfs/src/common-utils.h
+++ b/libglusterfs/src/common-utils.h
@@ -328,5 +328,7 @@ int gf_unlockfd (int fd);
 int get_checksum_for_file (int fd, uint32_t *checksum);
 int log_base2 (unsigned long x);
 
+int gf_system (const char *command);
+
 #endif /* _COMMON_UTILS_H */