ecpg threading vs win32

This patch replaces the pthreads code in ecpg with native win32 threads,
in order to make it threadsafe. The idea is not to have to download the
non-standard pthreads library on windows.

Does it seem like it should be doing the right thing? Does somebody have
a good test-case where ecpg breaks when not built thread-safe? (which
would then also break when built thread-safe with a broken implementation)

//Magnus
Index: connect.c
===================================================================
RCS file: /projects/cvsroot/pgsql/src/interfaces/ecpg/ecpglib/connect.c,v
retrieving revision 1.39
diff -u -r1.39 connect.c
--- connect.c    12 Jan 2007 10:00:12 -0000    1.39
+++ connect.c    14 Mar 2007 12:47:48 -0000
@@ -4,7 +4,11 @@
 #include "postgres_fe.h"

 #ifdef ENABLE_THREAD_SAFETY
+#ifndef WIN32
 #include <pthread.h>
+#else
+#include "ecpg-pthread-win32.h"
+#endif
 #endif
 #include "ecpgtype.h"
 #include "ecpglib.h"
@@ -13,9 +17,14 @@
 #include "sqlca.h"

 #ifdef ENABLE_THREAD_SAFETY
+#ifndef WIN32
 static pthread_mutex_t connections_mutex = PTHREAD_MUTEX_INITIALIZER;
 static pthread_key_t actual_connection_key;
 static pthread_once_t actual_connection_key_once = PTHREAD_ONCE_INIT;
+#else
+static HANDLE connections_mutex = INVALID_HANDLE_VALUE;
+static DWORD actual_connection_key;
+#endif /* WIN32 */
 #endif
 static struct connection *actual_connection = NULL;
 static struct connection *all_connections = NULL;
@@ -30,7 +39,13 @@
 void
 ecpg_pthreads_init(void)
 {
+#ifndef WIN32
     pthread_once(&actual_connection_key_once, ecpg_actual_connection_init);
+#else
+    static long has_run = 0;
+    if (InterlockedCompareExchange(&has_run, 1, 0) == 0)
+        ecpg_actual_connection_init();
+#endif
 }
 #endif

Index: misc.c
===================================================================
RCS file: /projects/cvsroot/pgsql/src/interfaces/ecpg/ecpglib/misc.c,v
retrieving revision 1.34
diff -u -r1.34 misc.c
--- misc.c    12 Jan 2007 10:00:13 -0000    1.34
+++ misc.c    14 Mar 2007 12:48:03 -0000
@@ -6,7 +6,11 @@
 #include <limits.h>
 #include <unistd.h>
 #ifdef ENABLE_THREAD_SAFETY
+#ifndef WIN32
 #include <pthread.h>
+#else
+#include "ecpg-pthread-win32.h"
+#endif
 #endif
 #include "ecpgtype.h"
 #include "ecpglib.h"
@@ -58,9 +62,13 @@
 };

 #ifdef ENABLE_THREAD_SAFETY
+#ifndef WIN32
 static pthread_key_t sqlca_key;
 static pthread_once_t sqlca_key_once = PTHREAD_ONCE_INIT;
 #else
+static DWORD sqlca_key;
+#endif
+#else
 static struct sqlca_t sqlca =
 {
     {
@@ -90,8 +98,13 @@
 #endif

 #ifdef ENABLE_THREAD_SAFETY
+#ifndef WIN32
 static pthread_mutex_t debug_mutex = PTHREAD_MUTEX_INITIALIZER;
 static pthread_mutex_t debug_init_mutex = PTHREAD_MUTEX_INITIALIZER;
+#else
+static HANDLE debug_mutex = INVALID_HANDLE_VALUE;
+static HANDLE debug_init_mutex = INVALID_HANDLE_VALUE;
+#endif /* WIN32 */
 #endif
 static int    simple_debug = 0;
 static FILE *debugstream = NULL;
@@ -138,8 +151,13 @@
 {
 #ifdef ENABLE_THREAD_SAFETY
     struct sqlca_t *sqlca;
-
+#ifdef WIN32
+    static long has_run = 0;
+    if (InterlockedCompareExchange(&has_run, 1, 0) == 0)
+        ecpg_sqlca_key_init();
+#else
     pthread_once(&sqlca_key_once, ecpg_sqlca_key_init);
+#endif

     sqlca = pthread_getspecific(sqlca_key);
     if (sqlca == NULL)

/* $PostgreSQL$ */
/*
 * pthread mapping macros for win32 native thread implementation
 */
#ifndef _ECPG_PTHREAD_WIN32_H
#define _ECPG_PTHREAD_WIN32_H
#define pthread_mutex_lock(x) do { \
    if (*x == INVALID_HANDLE_VALUE) \
       *x = CreateMutex(NULL, FALSE, NULL); \
    WaitForSingleObject(*x, INFINITE); \
} while (0);
#define pthread_mutex_unlock(x) ReleaseMutex(*x)
#define pthread_getspecific(x) TlsGetValue(x)
#define pthread_setspecific(x,y) TlsSetValue(x,y)
#define pthread_key_create(x,y) *x = TlsAlloc();
#endif