[Qemu-devel] [PATCH] Avoiding extra iterations while closing file fd

[Pankaj Gupta]

Avoiding iterations for fd 0, 1 & 2 when we are closing file fds in child 
process.

Signed-off-by: Pankaj Gupta <address@hidden>
---
 net/tap.c | 14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)

diff --git a/net/tap.c b/net/tap.c
index 2d5099b..3253838 100644
--- a/net/tap.c
+++ b/net/tap.c
@@ -364,11 +364,8 @@ static int launch_script(const char *setup_script, const 
char *ifname, int fd)
     if (pid == 0) {
         int open_max = sysconf(_SC_OPEN_MAX), i;
 
-        for (i = 0; i < open_max; i++) {
-            if (i != STDIN_FILENO &&
-                i != STDOUT_FILENO &&
-                i != STDERR_FILENO &&
-                i != fd) {
+        for (i = 3; i < open_max; i++) {
+            if (i != fd) {
                 close(i);
             }
         }
@@ -449,11 +446,8 @@ static int net_bridge_run_helper(const char *helper, const 
char *bridge)
         char br_buf[6+IFNAMSIZ] = {0};
         char helper_cmd[PATH_MAX + sizeof(fd_buf) + sizeof(br_buf) + 15];
 
-        for (i = 0; i < open_max; i++) {
-            if (i != STDIN_FILENO &&
-                i != STDOUT_FILENO &&
-                i != STDERR_FILENO &&
-                i != sv[1]) {
+        for (i = 3; i < open_max; i++) {
+            if (i != sv[1]) {
                 close(i);
             }
         }
-- 
1.8.3.1