database/postgres
database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-04-27 22:56:53 +03:00
Code

> win32 doesn't support a static initializer for mutexes, thus the first

Browse Source 
> user must initialize the lock. The problem are concurrent "first" users
> - the pthread_mutex_t initialization must be synchronized.
> The current implementation is broken, the attached patches fixes that:
> mutex_initlock is a spinlock. If the pthread_mutex_t mutex is not
> initialized, then the spinlock is acquired, if the pthread_mutex_t is
> initialized if it's not yet initialized and then the spinlock is dropped.

Manfred Spraul
This commit is contained in:
Bruce Momjian 2004-07-12 14:23:28 +00:00
parent a29d26a3cd
commit f4c5e06edf
2 changed files with 22 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
src/interfaces/libpq/fe-connect.c
View File

@ -8,7 +8,7 @@
* *
* *
* IDENTIFICATION * IDENTIFICATION
* $PostgreSQL: pgsql/src/interfaces/libpq/fe-connect.c,v 1.277 2004/07/12 14:16:28 momjian Exp $ * $PostgreSQL: pgsql/src/interfaces/libpq/fe-connect.c,v 1.278 2004/07/12 14:23:28 momjian Exp $
* *
*------------------------------------------------------------------------- *-------------------------------------------------------------------------
*/ */
@ -3193,10 +3193,16 @@ default_threadlock(int acquire)
#ifndef WIN32 #ifndef WIN32
static pthread_mutex_t singlethread_lock = PTHREAD_MUTEX_INITIALIZER; static pthread_mutex_t singlethread_lock = PTHREAD_MUTEX_INITIALIZER;
#else #else
static pthread_mutex_t singlethread_lock; static pthread_mutex_t singlethread_lock = NULL;
static long mutex_initialized = 0; static long mutex_initlock = 0;
if (!InterlockedExchange(&mutex_initialized, 1L))
if (singlethread_lock == NULL) {
while(InterlockedExchange(&mutex_initlock, 1) == 1)
/* loop, another thread own the lock */ ;
if (singlethread_lock == NULL)
pthread_mutex_init(&singlethread_lock, NULL); pthread_mutex_init(&singlethread_lock, NULL);
InterlockedExchange(&mutex_initlock,0);
}
#endif #endif
if (acquire) if (acquire)
pthread_mutex_lock(&singlethread_lock); pthread_mutex_lock(&singlethread_lock);

14
src/interfaces/libpq/fe-secure.c
View File

@ -11,7 +11,7 @@
* *
* *
* IDENTIFICATION * IDENTIFICATION
* $PostgreSQL: pgsql/src/interfaces/libpq/fe-secure.c,v 1.44 2004/07/12 14:16:28 momjian Exp $ * $PostgreSQL: pgsql/src/interfaces/libpq/fe-secure.c,v 1.45 2004/07/12 14:23:28 momjian Exp $
* *
* NOTES * NOTES
* The client *requires* a valid server certificate. Since * The client *requires* a valid server certificate. Since
@ -867,10 +867,16 @@ init_ssl_system(PGconn *conn)
#ifndef WIN32 #ifndef WIN32
static pthread_mutex_t init_mutex = PTHREAD_MUTEX_INITIALIZER; static pthread_mutex_t init_mutex = PTHREAD_MUTEX_INITIALIZER;
#else #else
static pthread_mutex_t init_mutex; static pthread_mutex_t init_mutex = NULL;
static long mutex_initialized = 0L; static long mutex_initlock = 0;
if (!InterlockedExchange(&mutex_initialized, 1L))
if (init_mutex == NULL) {
while(InterlockedExchange(&mutex_initlock, 1) == 1)
/* loop, another thread own the lock */ ;
if (init_mutex == NULL)
pthread_mutex_init(&init_mutex, NULL); pthread_mutex_init(&init_mutex, NULL);
InterlockedExchange(&mutex_initlock,0);
}
#endif #endif
pthread_mutex_lock(&init_mutex); pthread_mutex_lock(&init_mutex);