Mark simple file and socket descriptors as uninheritable.

This patch creates two utility functions:

  int open_cloexec(pathname, flags)
  int create_cloexec(pathname, flags, mode)

These return a file descriptor with the CLOEXEC flag set, to ensure
that the descriptor is not inherited across a fork/exec operation.

The sockets returned by:

   _x_io_tcp_connect_ipv4()
   _x_io_tcp_connect()

now also have their CLOEXEC flag set.

1 files changed, 20 insertions, 0 deletions

diff --git a/src/xine-engine/io_helper.c b/src/xine-engine/io_helper.c
index b06c47709..5bcd95c63 100644
--- a/src/xine-engine/io_helper.c
+++ b/src/xine-engine/io_helper.c
@@ -67,6 +67,16 @@ static int _x_io_tcp_connect_ipv4(xine_stream_t *stream, const char *host, int p
   }
 
 #ifndef WIN32
+  if (fcntl(s, F_SETFD, FD_CLOEXEC) < 0) {
+    xprintf(stream->xine, XINE_VERBOSITY_DEBUG, "Failed to make socket uninheritable (%s)\n", strerror(errno));
+  }
+#else
+  if (!SetHandleInformation((HANDLE)s, HANDLE_FLAG_INHERIT, 0)) {
+    xprintf(stream->xine, XINE_VERBOSITY_DEBUG, "Failed to make socket uninheritable\n");
+  }
+#endif
+
+#ifndef WIN32
   if (fcntl (s, F_SETFL, fcntl (s, F_GETFL) | O_NONBLOCK) == -1) {
     _x_message(stream, XINE_MSG_CONNECTION_REFUSED, "can't put socket in non-blocking mode", strerror(errno), NULL);
     return -1;
@@ -152,6 +162,16 @@ int _x_io_tcp_connect(xine_stream_t *stream, const char *host, int port) {
 	  continue;
       }
 
+#ifndef WIN32
+      if (fcntl(s, F_SETFD, FD_CLOEXEC) < 0) {
+          xprintf(stream->xine, XINE_VERBOSITY_DEBUG, "Failed to make socket uninheritable (%s)\n", strerror(errno));
+      }
+#else
+      if (!SetHandleInformation((HANDLE)s, HANDLE_FLAG_INHERIT, 0)) {
+          xprintf(stream->xine, XINE_VERBOSITY_DEBUG, "Failed to make socket uninheritable\n");
+      }
+#endif
+
       /*
        * Enable the non-blocking features only when there's no other
        * address, allowing to use other addresses if available.