diff options
| author | Kenneth Soerensen <kenneth.sorensen@spectralink.com> | 2013-04-10 16:52:52 +0200 |
|---|---|---|
| committer | Bernhard Reutner-Fischer <rep.dot.nop@gmail.com> | 2013-11-12 16:12:32 +0100 |
| commit | ecc7aee9a0eb4f9fbdf4dc2972e8c6361e531b6a (patch) | |
| tree | 5a7d61dc209c68dcc2a02fd5556b171878ec34d1 /libc/inet/resolv.c | |
| parent | 20b69920b299585265eb100d0b67e1097ccb1092 (diff) | |
Make res_init() thread safe.
res_init() was not atomic, which could give undesired behaviour. Now
res_init() is completely locked under one lock and the locking is
removed from __res_vinit().
Signed-off-by: Kenneth Soerensen <kenneth.sorensen@spectralink.com>
Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
Diffstat (limited to 'libc/inet/resolv.c')
| -rw-r--r-- | libc/inet/resolv.c | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/libc/inet/resolv.c b/libc/inet/resolv.c index ae0dce520..f334d0586 100644 --- a/libc/inet/resolv.c +++ b/libc/inet/resolv.c @@ -3426,6 +3426,7 @@ static void res_sync_func(void) */ } +/* has to be called under __resolv_lock */ static int __res_vinit(res_state rp, int preinit) { @@ -3434,7 +3435,6 @@ __res_vinit(res_state rp, int preinit) int m = 0; #endif - __UCLIBC_MUTEX_LOCK(__resolv_lock); __close_nameservers(); __open_nameservers(); @@ -3526,7 +3526,6 @@ __res_vinit(res_state rp, int preinit) rp->options |= RES_INIT; - __UCLIBC_MUTEX_UNLOCK(__resolv_lock); return 0; } @@ -3576,11 +3575,11 @@ res_init(void) if (!_res.id) _res.id = res_randomid(); - __UCLIBC_MUTEX_UNLOCK(__resolv_lock); - __res_vinit(&_res, 1); __res_sync = res_sync_func; + __UCLIBC_MUTEX_UNLOCK(__resolv_lock); + return 0; } libc_hidden_def(res_init) @@ -3679,7 +3678,11 @@ struct __res_state *__resp = &_res; int res_ninit(res_state statp) { - return __res_vinit(statp, 0); + int ret; + __UCLIBC_MUTEX_LOCK(__resolv_lock); + ret = __res_vinit(statp, 0); + __UCLIBC_MUTEX_UNLOCK(__resolv_lock); + return ret; } #endif /* L_res_init */ |