From 4290f79748cb6b333ecf82808f53e557b8184728 Mon Sep 17 00:00:00 2001
From: Jaroslav Kysela <perex@perex.cz>
Date: Tue, 18 Nov 2014 09:10:48 +0100
Subject: [PATCH] spawn: allow spawnv stdout/stderr redirection to logs

---
 src/config.c      |  2 +-
 src/dvr/dvr_rec.c |  2 +-
 src/main.c        |  3 +--
 src/spawn.c       | 38 ++++++++++++++++++++++++++++++++------
 src/spawn.h       |  4 +---
 5 files changed, 36 insertions(+), 13 deletions(-)

diff --git a/src/config.c b/src/config.c
index 914a4907..ea1e93f5 100644
--- a/src/config.c
+++ b/src/config.c
@@ -1147,7 +1147,7 @@ dobackup(const char *oldver)
                                      root, oldver);
   tvhinfo("config", "backup: running, output file %s", outfile);
 
-  spawnv(argv[0], (void *)argv);
+  spawnv(argv[0], (void *)argv, 1, 1);
 
   while ((code = spawn_reap(errtxt, sizeof(errtxt))) == -EAGAIN)
     usleep(20000);
diff --git a/src/dvr/dvr_rec.c b/src/dvr/dvr_rec.c
index 39be2d24..d80c0cd8 100644
--- a/src/dvr/dvr_rec.c
+++ b/src/dvr/dvr_rec.c
@@ -679,7 +679,7 @@ dvr_spawn_postproc(dvr_entry_t *de, const char *dvr_postproc)
     args[i] = s;
   }
   
-  spawnv(args[0], (void *)args);
+  spawnv(args[0], (void *)args, 1, 1);
     
   htsstr_argsplit_free(args);
 }
diff --git a/src/main.c b/src/main.c
index b2eac04b..3420fcf9 100644
--- a/src/main.c
+++ b/src/main.c
@@ -787,14 +787,13 @@ main(int argc, char **argv)
   /* Initialise configuration */
   uuid_init();
   idnode_init();
+  spawn_init();
   config_init(opt_config, opt_nobackup == 0);
 
   /**
    * Initialize subsystems
    */
 
-  spawn_init();
-
   dbus_server_init(opt_dbus, opt_dbus_session);
 
   intlconv_init();
diff --git a/src/spawn.c b/src/spawn.c
index a686ab55..4cfb48a9 100644
--- a/src/spawn.c
+++ b/src/spawn.c
@@ -60,6 +60,8 @@ typedef struct spawn {
   const char *name;
 } spawn_t;
 
+static void spawn_reaper(void);
+
 /*
  *
  */
@@ -274,7 +276,7 @@ spawn_reap(char *stxt, size_t stxtlen)
 /**
  * The reaper is called once a second to finish of any pending spawns
  */
-void
+static void
 spawn_reaper(void)
 {
   while (spawn_reap(NULL, 0) != -EAGAIN) ;
@@ -343,12 +345,15 @@ spawn_and_give_stdout(const char *prog, char *argv[], int *rd, int redir_stderr)
     }
 
     close(0);
+    close(1);
     close(2);
-    close(fd[0]);
-    dup2(fd[1], 1);
-    close(fd[1]);
+
     dup2(f, 0);
+    dup2(fd[1], 1);
     dup2(redir_stderr ? spawn_pipe_error.wr : f, 2);
+
+    close(fd[0]);
+    close(fd[1]);
     close(f);
 
     spawn_info("Executing \"%s\"\n", prog);
@@ -379,9 +384,9 @@ spawn_and_give_stdout(const char *prog, char *argv[], int *rd, int redir_stderr)
  * The function will return the size of the buffer
  */
 int
-spawnv(const char *prog, char *argv[])
+spawnv(const char *prog, char *argv[], int redir_stdout, int redir_stderr)
 {
-  pid_t p;
+  pid_t p, f, maxfd;
   char bin[256];
   const char *local_argv[2] = { NULL, NULL };
 
@@ -393,6 +398,8 @@ spawnv(const char *prog, char *argv[])
   if(!argv) argv = (void *)local_argv;
   if (!argv[0]) argv[0] = (char*)prog;
 
+  maxfd = sysconf(_SC_OPEN_MAX);
+
   pthread_mutex_lock(&fork_lock);
 
   p = fork();
@@ -405,9 +412,28 @@ spawnv(const char *prog, char *argv[])
   }
 
   if(p == 0) {
+    f = open("/dev/null", O_RDWR);
+    if(f == -1) {
+      spawn_error("pid %d cannot open /dev/null for redirect %s -- %s",
+                  getpid(), prog, strerror(errno));
+      exit(1);
+    }
+
     close(0);
+    close(1);
     close(2);
+
+    dup2(f, 0);
+    dup2(redir_stdout ? spawn_pipe_info.wr : f, 1);
+    dup2(redir_stderr ? spawn_pipe_error.wr : f, 2);
+
+    close(f);
+
     spawn_info("Executing \"%s\"\n", prog);
+
+    for (f = 3; f < maxfd; f++)
+      close(f);
+
     execve(prog, argv, environ);
     spawn_error("pid %d cannot execute %s -- %s\n",
 	        getpid(), prog, strerror(errno));
diff --git a/src/spawn.h b/src/spawn.h
index 882d4c69..81b1951b 100644
--- a/src/spawn.h
+++ b/src/spawn.h
@@ -27,12 +27,10 @@ int find_exec ( const char *name, char *out, size_t len );
 
 int spawn_and_give_stdout(const char *prog, char *argv[], int *rd, int redir_stderr);
 
-int spawnv(const char *prog, char *argv[]);
+int spawnv(const char *prog, char *argv[], int redir_stdout, int redir_stderr);
 
 int spawn_reap(char *stxt, size_t stxtlen);
 
-void spawn_reaper(void);
-
 void spawn_init(void);
 
 void spawn_done(void);