[Qemu-devel] [PATCH] Fix tap downscript argument

[Mark McLoughlin <markmc@redhat.com>]

Kill off the hack that parses info_str for the tap interface
name to pass as the argument to the downscript and, instead,
just explicitly keep a copy of the string for later.

As reported by John Wong, this commit:

  Add qemu_format_nic_info_str()

changed the invocation of downscript from e.g.

  /path/kvm-ifdown "tap0"

to:

  /path/kvm-ifdown "tap0,script=/path/kvm-ifup,downscript=/path/kvm-ifdown"

This fix restores the original behavior.

Reported-by: John Wong <johnw@wonghome.net>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
---
 net.c |   12 ++++++------
 1 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/net.c b/net.c
index 30ba717..e6639ec 100644
--- a/net.c
+++ b/net.c
@@ -652,6 +652,7 @@ typedef struct TAPState {
     VLANClientState *vc;
     int fd;
     char down_script[1024];
+    char down_script_arg[128];
 } TAPState;
 
 #ifdef HAVE_IOVEC
@@ -978,8 +979,10 @@ static int net_tap_init(VLANState *vlan, const char *model,
     snprintf(s->vc->info_str, sizeof(s->vc->info_str),
              "ifname=%s,script=%s,downscript=%s",
              ifname, setup_script, down_script);
-    if (down_script && strcmp(down_script, "no"))
+    if (down_script && strcmp(down_script, "no")) {
         snprintf(s->down_script, sizeof(s->down_script), "%s", down_script);
+        snprintf(s->down_script_arg, sizeof(s->down_script_arg), "%s", ifname);
+    }
     return 0;
 }
 
@@ -1736,13 +1739,10 @@ void net_cleanup(void)
 
         for(vc = vlan->first_client; vc != NULL; vc = vc->next) {
             if (vc->fd_read == tap_receive) {
-                char ifname[64];
                 TAPState *s = vc->opaque;
 
-                if (strcmp(vc->model, "tap") == 0 &&
-                    sscanf(vc->info_str, "ifname=%63s ", ifname) == 1 &&
-                    s->down_script[0])
-                    launch_script(s->down_script, ifname, s->fd);
+                if (s->down_script[0])
+                    launch_script(s->down_script, s->down_script_arg, s->fd);
             }
 #if defined(CONFIG_VDE)
             if (vc->fd_read == vde_from_qemu) {
-- 
1.6.1