[windows] Use critical section when pthread mutex is not available

When compiling for Windows, pthread libraries may not be available. In
this case, we emulate pthread mutexes with critical sections.

CMakeLists.txt

@@ -156,6 +156,20 @@ ck_check_include_file("sys/time.h" HAVE_SYS_TIME_H)
 ck_check_include_file("time.h" HAVE_TIME_H)
 ck_check_include_file("unistd.h" HAVE_UNISTD_H)
 
+# check if we have windows.h on native windows environments
+ck_check_include_file("windows.h" HAVE_WINDOWS_H)
+ck_check_include_file("synchapi.h" HAVE_SYNCHAPI_H)
+if (HAVE_WINDOWS_H)
+  set(HAVE_WINDOWS_H 1)
+else()
+  set(HAVE_WINDOWS_H 0)
+endif()
+if (HAVE_SYNCHAPI_H)
+  set(HAVE_SYNCHAPI_H 1)
+else()
+  set(HAVE_SYNCHAPI_H 0)
+endif()
+
 ###############################################################################
 # Check functions
 check_function_exists(fork HAVE_FORK)
@@ -173,10 +187,20 @@ check_function_exists(strsignal HAVE_DECL_STRSIGNAL)
 check_function_exists(_getpid HAVE__GETPID)
 check_function_exists(_strdup HAVE__STRDUP)
 check_function_exists(alarm HAVE_DECL_ALARM)
+if (HAVE_SYNCHAPI_H)
+  check_function_exists(InitOnceBeginInitialize HAVE_INIT_ONCE_BEGIN_INITIALIZE)
+  check_function_exists(InitOnceComplete HAVE_INIT_ONCE_COMPLETE)
+endif()
 if (HAVE_REGEX_H)
   check_function_exists(regcomp HAVE_REGCOMP)
   check_function_exists(regexec HAVE_REGEXEC)
 endif()
+if (HAVE_INIT_ONCE_BEGIN_INITIALIZE AND HAVE_INIT_ONCE_COMPLETE)
+  set(HAVE_WIN32_INIT_ONCE 1)
+else()
+  set(HAVE_WIN32_INIT_ONCE 0)
+endif()
+
 
 # printf related checks
 check_function_exists(snprintf HAVE_SNPRINTF_FUNCTION)

configure.ac

@@ -271,6 +271,21 @@ AM_CONDITIONAL(SUBUNIT, test x"$enable_subunit" != "xfalse")
 # Check for POSIX regular expressions support.
 AC_CHECK_HEADERS([regex.h], HAVE_REGEX_H=1, HAVE_REGEX_H=0)
 
+# Check if we have the windows headers for Init Once API
+AC_CHECK_HEADERS([windows.h], HAVE_WINDOWS_H=1, HAVE_WINDOWS_H=0)
+AC_CHECK_HEADERS([synchapi.h], HAVE_SYNCHAPI_H=1, HAVE_SYNCHAPI_H=0)
+AC_SUBST(HAVE_WINDOWS_H)
+AC_SUBST(HAVE_SYNCHAPI_H)
+
+# Check if we have the One-Time Initialization API
+if test "x$HAVE_SYNCHAPI_H" = "x1"; then
+    AC_CHECK_FUNCS([InitOnceBeginInitialize InitOnceComplete], HAVE_WIN32_INIT_ONCE=1, HAVE_WIN32_INIT_ONCE=0)
+else
+    HAVE_WIN32_INIT_ONCE=0
+fi
+AC_SUBST(HAVE_WIN32_INIT_ONCE)
+AC_DEFINE_UNQUOTED(HAVE_WIN32_INIT_ONCE, $HAVE_WIN32_INIT_ONCE, "Win32 Init Once API is supported")
+
 if test "x$HAVE_REGEX_H" = "x1"; then
     AC_CHECK_FUNCS([regcomp regexec], HAVE_REGEX=1, HAVE_REGEX=0)
 else

src/check.h.in

@@ -2357,4 +2357,8 @@ CK_DLL_EXP void CK_EXPORT check_set_max_msg_size(size_t max_msg_size);
 CK_CPPEND
 #endif
 
+#define HAVE_WINDOWS_H @HAVE_WINDOWS_H@
+#define HAVE_SYNCHAPI_H @HAVE_SYNCHAPI_H@
+#define HAVE_WIN32_INIT_ONCE @HAVE_WIN32_INIT_ONCE@
+
 #endif /* CHECK_H */

src/check_pack.c

@@ -33,13 +33,29 @@
 #include "check_impl.h"
 #include "check_pack.h"
 
+#if HAVE_WINDOWS_H
+#include <windows.h>
+#endif
+
+#if HAVE_SYNCHAPI_H
+#include <synchapi.h>
+#endif
+
 #ifndef HAVE_PTHREAD
-#define pthread_mutex_lock(arg)
-#define pthread_mutex_unlock(arg)
 #define pthread_cleanup_push(f, a) {
 #define pthread_cleanup_pop(e) }
 #endif
 
+#ifndef HAVE_PTHREAD
+#if HAVE_WIN32_INIT_ONCE
+#define pthread_mutex_lock(arg) EnterCriticalSection(arg)
+#define pthread_mutex_unlock(arg) LeaveCriticalSection(arg)
+#else
+#define pthread_mutex_lock(arg)
+#define pthread_mutex_unlock(arg)
+#endif
+#endif
+
 /* Maximum size for one message in the message stream. */
 static size_t ck_max_msg_size = 0;
 #ifndef DEFAULT_MAX_MSG_SIZE
@@ -348,12 +364,15 @@ static void check_type(int type, const char *file, int line)
         eprintf("Bad message type arg %d", file, line, type);
 }
 
-#ifdef HAVE_PTHREAD
+#if defined HAVE_PTHREAD
 static pthread_mutex_t ck_mutex_lock = PTHREAD_MUTEX_INITIALIZER;
 static void ppack_cleanup(void *mutex)
 {
     pthread_mutex_unlock((pthread_mutex_t *)mutex);
 }
+#elif HAVE_WIN32_INIT_ONCE
+static INIT_ONCE init_once = INIT_ONCE_STATIC_INIT;
+static CRITICAL_SECTION ck_mutex_lock;
 #endif
 
 void ppack(FILE * fdes, enum ck_msg_type type, CheckMsg * msg)
@@ -362,6 +381,20 @@ void ppack(FILE * fdes, enum ck_msg_type type, CheckMsg * msg)
     int n;
     size_t r;
 
+#if !defined HAVE_PTHREAD && HAVE_WIN32_INIT_ONCE
+    BOOL pending;
+    if (!InitOnceBeginInitialize(&init_once, 0, &pending, NULL))
+    {
+        eprintf("Cannot initialize Win32 synch object", __FILE__, __LINE__ - 5);
+        return;
+    }
+
+    if (pending)
+        InitializeCriticalSection(&ck_mutex_lock);
+
+    InitOnceComplete(&init_once, 0, NULL);
+#endif
+
     n = pack(type, &buf, msg);
     if(n < 0)
         eprintf("pack failed", __FILE__, __LINE__ - 2);