In the capture_loop.c code, open the capture device for input before

doing anything with the output file, so that

	1) if the attempt to open the capture device fails, we don't
	   bother creating any output files;

	2) we could relinquish privileges permanently as soon as we
	   finish opening the capture device, so we don't have to give
	   them up temporarily when opening the output file, reclaim
	   them to open the input device, and then give them up
	   permanently;

(we already do that in Tethereal).

While we're at it, set the capture filter immediately after opening the
capture device, so we quit before opening capture devices if that fails.

svn path=/trunk/; revision=17468

1 files changed, 6 insertions, 6 deletions

diff --git a/tethereal.c b/tethereal.c
index 176607996b..30176210d9 100644
--- a/tethereal.c
+++ b/tethereal.c
@@ -1548,12 +1548,6 @@ capture(void)
    */
   relinquish_special_privs_perm();
 
-  /* open the output file (temporary/specified name/ringbuffer/named pipe/stdout) */
-  if (!capture_loop_open_output(&capture_opts, &save_file_fd, errmsg, sizeof(errmsg))) {
-    *secondary_errmsg = '\0';
-    goto error;    
-  }
-
   /* init the input filter from the network interface (capture pipe will do nothing) */
   switch (capture_loop_init_filter(ld.pcap_h, ld.from_cap_pipe, capture_opts.iface, capture_opts.cfilter)) {
 
@@ -1573,6 +1567,12 @@ capture(void)
     goto error;
   }
 
+  /* open the output file (temporary/specified name/ringbuffer/named pipe/stdout) */
+  if (!capture_loop_open_output(&capture_opts, &save_file_fd, errmsg, sizeof(errmsg))) {
+    *secondary_errmsg = '\0';
+    goto error;    
+  }
+
   /* set up to write to the already-opened capture output file/files */
   if(!capture_loop_init_output(&capture_opts, save_file_fd, &ld, errmsg, sizeof errmsg)) {
     *secondary_errmsg = '\0';