Monitor: improve check_one_sharer() for checking duplicated process

[thirdparty/mdadm.git] / Monitor.c

diff --git a/Monitor.c b/Monitor.c
index b527165b803acc2eb3a9d84132f44a39f64aeba1..2d6b3b9016e4e4f608e230bfe16e1642c5875016 100644 (file)
--- a/Monitor.c
+++ b/Monitor.c
@@ -301,26 +301,34 @@ static int make_daemon(char *pidfile)
 
 static int check_one_sharer(int scan)
 {
-       int pid, rv;
+       int pid;
+       FILE *comm_fp;
        FILE *fp;
-       char dir[20];
+       char comm_path[100];
        char path[100];
-       struct stat buf;
+       char comm[20];
+
        sprintf(path, "%s/autorebuild.pid", MDMON_DIR);
        fp = fopen(path, "r");
        if (fp) {
                if (fscanf(fp, "%d", &pid) != 1)
                        pid = -1;
-               sprintf(dir, "/proc/%d", pid);
-               rv = stat(dir, &buf);
-               if (rv != -1) {
-                       if (scan) {
-                               pr_err("Only one autorebuild process allowed in scan mode, aborting\n");
-                               fclose(fp);
-                               return 1;
-                       } else {
-                               pr_err("Warning: One autorebuild process already running.\n");
+               snprintf(comm_path, sizeof(comm_path),
+                        "/proc/%d/comm", pid);
+               comm_fp = fopen(comm_path, "r");
+               if (comm_fp) {
+                       if (fscanf(comm_fp, "%s", comm) &&
+                           strncmp(basename(comm), Name, strlen(Name)) == 0) {
+                               if (scan) {
+                                       pr_err("Only one autorebuild process allowed in scan mode, aborting\n");
+                                       fclose(comm_fp);
+                                       fclose(fp);
+                                       return 1;
+                               } else {
+                                       pr_err("Warning: One autorebuild process already running.\n");
+                               }
                        }
+                       fclose(comm_fp);
                }
                fclose(fp);
        }