From 52dba6418ee96fb3ac2b47a7edd19821323b382f Mon Sep 17 00:00:00 2001
From: Philippe Pepiot <phil@philpep.org>
Date: Tue, 20 Apr 2010 03:32:22 +0200
Subject: [PATCH] fix posible issue with statusbar when reloading wmfs spawn()
 now return the child pid

---
 src/init.c    | 20 +++++--------------
 src/structs.h |  1 +
 src/util.c    | 53 +++++++++++++++++++++++++++++++++++++--------------
 src/wmfs.c    |  5 ++++-
 src/wmfs.h    |  4 +++-
 5 files changed, 52 insertions(+), 31 deletions(-)

diff --git a/src/init.c b/src/init.c
index 50bd4f1..6a9b853 100644
--- a/src/init.c
+++ b/src/init.c
@@ -180,45 +180,35 @@ init_root(void)
 void
 init_status(void)
 {
-     int fd;
      struct stat st;
      char *home;
 
+     conf.status_pid = -1;
+     estatus = False;
+
      if(!conf.status_path)
      {
           if(!(home = getenv("HOME")))
           {
                warnx("HOME not set, can't launch status.sh");
-               estatus = False;
                return;
           }
 
           conf.status_path = emalloc(strlen(home) + strlen(DEF_STATUS) + 2, sizeof(char));
-
           sprintf(conf.status_path, "%s/"DEF_STATUS, home);
      }
 
-     if(!(fd = open(conf.status_path, O_RDONLY))
-               || !fopen(conf.status_path, "r"))
+     if (stat(conf.status_path, &st) == -1)
      {
-          free(conf.status_path);
-          estatus = False;
-
+          warn("%s", conf.status_path);
           return;
      }
 
-     stat(conf.status_path, &st);
-
      if(st.st_size && st.st_mode & S_IXUSR)
-     {
           estatus = True;
-          spawn(conf.status_path);
-     }
      else
           warnx("status file specified in configuratin (status_path) or present in wmfs directory can't be executed, try 'chmod +x %s'.", conf.status_path);
 
-     close(fd);
-
      return;
 }
 
diff --git a/src/structs.h b/src/structs.h
index b7e6122..38df242 100644
--- a/src/structs.h
+++ b/src/structs.h
@@ -348,6 +348,7 @@ typedef struct
      uint pad;
      int status_timing;
      char *status_path;
+     pid_t status_pid;
      char *autostart_path;
      char *autostart_command;
      struct
diff --git a/src/util.c b/src/util.c
index d50d934..8e5973a 100644
--- a/src/util.c
+++ b/src/util.c
@@ -200,44 +200,69 @@ get_mouse_pos(void)
 
 /** Execute a sh command
  * \param cmd Command
+ * \return child pid
 */
-void
+int
 spawn(const char *format, ...)
 {
      char *sh = NULL;
      char cmd[512];
      va_list ap;
-
-     if(strlen(format) > 511)
-     {
-          warnx("spawn(): Error, command too long.");
-          return;
-     }
+     pid_t pid, ret;
+     int p[2], len;
 
      va_start(ap, format);
-     vsprintf(cmd, format, ap);
+     len = vsnprintf(cmd, sizeof(cmd), format, ap);
      va_end(ap);
 
-     if(!strlen(cmd))
-          return;
+     if (len >= sizeof(cmd))
+     {
+          warnx("command too long (> 512 bytes)");
+          return -1;
+     }
 
      if(!(sh = getenv("SHELL")))
           sh = "/bin/sh";
 
-     if(fork() == 0)
+     if (pipe(p) == -1)
      {
-          if(fork() == 0)
+          warn("pipe");
+          return -1;
+     }
+
+     if((pid = fork()) == 0)
+     {
+          close(p[0]);
+          if((pid = fork()) == 0)
           {
                if(dpy)
                     close(ConnectionNumber(dpy));
                setsid();
                execl(sh, sh, "-c", cmd, (char*)NULL);
-               exit(EXIT_SUCCESS);
+               exit(EXIT_FAILURE);
           }
+          write(p[1], &pid, sizeof(pid_t));
+          close(p[1]);
           exit(EXIT_SUCCESS);
      }
+     else if (pid != -1)
+     {
+          close(p[1]);
+          if (sizeof(pid_t) != read(p[0], &ret, sizeof(pid_t)))
+          {
+               warn("read");
+               ret = -1;
+          }
+          close(p[0]);
+          waitpid(pid, NULL, 0);
+     }
+     else
+     {
+          warn("fork");
+          ret = -1;
+     }
 
-     return;
+     return ret;
 }
 
 /** Swap two pointer.
diff --git a/src/wmfs.c b/src/wmfs.c
index b868673..d2f82ba 100644
--- a/src/wmfs.c
+++ b/src/wmfs.c
@@ -148,7 +148,7 @@ thread_process(void *arg)
           pthread_detach(pthread_self());
           do
           {
-               spawn(conf.status_path);
+               conf.status_pid = spawn(conf.status_path);
                sleep(conf.status_timing);
           } while (!exiting && conf.status_timing != 0);
      }
@@ -271,6 +271,9 @@ uicb_reload(uicb_t cmd)
 {
      quit();
 
+     if (conf.status_pid != (pid_t)-1)
+          kill(conf.status_pid, SIGQUIT);
+
      for(; argv_global[0] && argv_global[0] == ' '; ++argv_global);
 
      execlp(argv_global, argv_global, NULL);
diff --git a/src/wmfs.h b/src/wmfs.h
index 1ea6577..6726d02 100644
--- a/src/wmfs.h
+++ b/src/wmfs.h
@@ -33,6 +33,8 @@
 #ifndef WMFS_H
 #define WMFS_H
 
+#define _BSD_SOURCE /* vsnprintf */
+#define _POSIX_SOURCE /* kill */
 /* Lib headers */
 #include <stdio.h>
 #include <stdlib.h>
@@ -278,7 +280,7 @@ char* alias_to_str(char *conf_choice);
 /* }}} */
 XRectangle get_mouse_pos(void);
 char *char_to_str(const char c);
-void spawn(const char *str, ...);
+int spawn(const char *str, ...);
 void swap_ptr(void **x, void **y);
 void uicb_spawn(uicb_t);
 char *clean_value(char *str);