Add proper threading support to libgit2

We now depend on libpthread on all Unix platforms (should be installed
by default) and use a simple wrapper for Windows threads under Win32.

Signed-off-by: Vicent Marti <tanoku@gmail.com>

4 files changed, 209 insertions, 104 deletions

diff --git a/src/common.h b/src/common.h
index 1ca00471b..723085a2b 100644
--- a/src/common.h
+++ b/src/common.h
@@ -11,9 +11,6 @@
 #include "git2/thread-utils.h"
 #include "cc-compat.h"
 
-#ifdef GIT_HAS_PTHREAD
-# include <pthread.h>
-#endif
 #ifdef GIT_HAVE_INTTYPES_H
 # include <inttypes.h>
 #endif
@@ -34,6 +31,7 @@
 # include <windows.h>
 # include "msvc-compat.h"
 # include "mingw-compat.h"
+# include "win32/pthread.h"
 
 # define snprintf _snprintf
 
@@ -43,6 +41,7 @@ typedef SSIZE_T ssize_t;
 
 # include <unistd.h>
 # include <arpa/inet.h>
+# include <pthread.h>
 
 #endif
 
diff --git a/src/thread-utils.h b/src/thread-utils.h
index 0029e4bc1..e8372e731 100644
--- a/src/thread-utils.h
+++ b/src/thread-utils.h
@@ -1,108 +1,27 @@
 #ifndef INCLUDE_thread_utils_h__
 #define INCLUDE_thread_utils_h__
 
-#if defined(GIT_HAS_PTHREAD)
-	typedef pthread_t git_thread;
-#	define git_thread_create(thread, attr, start_routine, arg) pthread_create(thread, attr, start_routine, arg)
-#	define git_thread_kill(thread) pthread_cancel(thread)
-#	define git_thread_exit(status)	pthread_exit(status)
-#	define git_thread_join(id, status) pthread_join(id, status)
 
-	/* Pthreads Mutex */
-	typedef pthread_mutex_t git_lck;
-#	define GITLCK_INIT      PTHREAD_MUTEX_INITIALIZER
-#	define gitlck_init(a)   pthread_mutex_init(a, NULL)
-#	define gitlck_lock(a)   pthread_mutex_lock(a)
-#	define gitlck_unlock(a) pthread_mutex_unlock(a)
-#	define gitlck_free(a)   pthread_mutex_destroy(a)
-
-	/* Pthreads condition vars */
-	typedef pthread_cond_t git_cnd;
-#	define GITCND_INIT			PTHREAD_COND_INITIALIZER
-#	define gitcnd_init(c, a)	pthread_cond_init(c, a)
-#	define gitcnd_free(c)		pthread_cond_destroy(c)
-#	define gitcnd_wait(c, l)	pthread_cond_wait(c, l)
-#	define gitcnd_signal(c)		pthread_cond_signal(c)
-#	define gitcnd_broadcast(c)	pthread_cond_broadcast(c)
-
-#	if defined(GIT_HAS_ASM_ATOMIC)
-#		include <asm/atomic.h>
-		typedef atomic_t git_refcnt;
-#		define gitrc_init(a, v) atomic_set(a, v)
-#		define gitrc_inc(a)		atomic_inc_return(a)
-#		define gitrc_dec(a)		atomic_dec_and_test(a)
-#		define gitrc_free(a)	(void)0
-#	elif defined(GIT_WIN32)
-		typedef long git_refcnt;
-#		define gitrc_init(a, v)	(*a = v)
-#		define gitrc_inc(a)		(InterlockedIncrement(a))
-#		define gitrc_dec(a)		(!InterlockedDecrement(a))
-#		define gitrc_free(a)	(void)0
-#	else
-		typedef struct { git_lck lock; int counter; } git_refcnt;
-
-		/** Initialize to 0.  No memory barrier is issued. */
-		GIT_INLINE(void) gitrc_init(git_refcnt *p, int value)
-		{
-			gitlck_init(&p->lock);
-			p->counter = value;
-		}
-
-		/**
-		 * Increment.
-		 *
-		 * Atomically increments @p by 1.  A memory barrier is also
-		 * issued before and after the operation.
-		 *
-		 * @param p pointer of type git_refcnt
-		 */
-		GIT_INLINE(void) gitrc_inc(git_refcnt *p)
-		{
-			gitlck_lock(&p->lock);
-			p->counter++;
-			gitlck_unlock(&p->lock);
-		}
-
-		/**
-		 * Decrement and test.
-		 *
-		 * Atomically decrements @p by 1 and returns true if the
-		 * result is 0, or false for all other cases.  A memory
-		 * barrier is also issued before and after the operation.
-		 *
-		 * @param p pointer of type git_refcnt
-		 */
-		GIT_INLINE(int) gitrc_dec(git_refcnt *p)
-		{
-			int c;
-			gitlck_lock(&p->lock);
-			c = --p->counter;
-			gitlck_unlock(&p->lock);
-			return !c;
-		}
-
-		/** Free any resources associated with the counter. */
-#		define gitrc_free(p) gitlck_free(&(p)->lock)
-#	endif
-
-#elif defined(GIT_THREADS)
-#	error GIT_THREADS but no git_lck implementation
-
-#else
-	/* no threads support */
-	typedef struct { int dummy; } git_lck;
-#	define GIT_MUTEX_INIT   {}
-#	define gitlck_init(a)   (void)0
-#	define gitlck_lock(a)   (void)0
-#	define gitlck_unlock(a) (void)0
-#	define gitlck_free(a)   (void)0
-
-	typedef struct { int counter; } git_refcnt;
-#	define gitrc_init(a,v) ((a)->counter = v)
-#	define gitrc_inc(a)    ((a)->counter++)
-#	define gitrc_dec(a)    (--(a)->counter == 0)
-#	define gitrc_free(a)   (void)0
-#endif
+#define git_thread pthread_t
+#define git_thread_create(thread, attr, start_routine, arg) pthread_create(thread, attr, start_routine, arg)
+#define git_thread_kill(thread) pthread_cancel(thread)
+#define git_thread_exit(status)	pthread_exit(status)
+#define git_thread_join(id, status) pthread_join(id, status)
+
+/* Pthreads Mutex */
+#define git_mutex pthread_mutex_t
+#define git_mutex_init(a)   pthread_mutex_init(a, NULL)
+#define git_mutex_lock(a)   pthread_mutex_lock(a)
+#define git_mutex_unlock(a) pthread_mutex_unlock(a)
+#define git_mutex_free(a)   pthread_mutex_destroy(a)
+
+/* Pthreads condition vars */
+#define git_cond pthread_cond_t
+#define git_cond_init(c, a)	pthread_cond_init(c, a)
+#define git_cond_free(c)		pthread_cond_destroy(c)
+#define git_cond_wait(c, l)	pthread_cond_wait(c, l)
+#define git_cond_signal(c)		pthread_cond_signal(c)
+#define git_cond_broadcast(c)	pthread_cond_broadcast(c)
 
 extern int git_online_cpus(void);
 
diff --git a/src/win32/pthread.c b/src/win32/pthread.c
new file mode 100644
index 000000000..fffff81df
--- /dev/null
+++ b/src/win32/pthread.c
@@ -0,0 +1,120 @@
+/*
+ * This file is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2,
+ * as published by the Free Software Foundation.
+ *
+ * In addition to the permissions in the GNU General Public License,
+ * the authors give you unlimited permission to link the compiled
+ * version of this file into combinations with other programs,
+ * and to distribute those combinations without any restriction
+ * coming from the use of this file.  (The General Public License
+ * restrictions do apply in other respects; for example, they cover
+ * modification of the file, and distribution when not linked into
+ * a combined executable.)
+ *
+ * This file is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING.  If not, write to
+ * the Free Software Foundation, 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ *
+ *  Original code by Ramiro Polla (Public Domain)
+ */
+
+#include "pthread.h"
+
+int pthread_create(pthread_t *GIT_RESTRICT thread,
+                   const pthread_attr_t *GIT_RESTRICT GIT_UNUSED(attr),
+                   void *(*start_routine)(void*), void *GIT_RESTRICT arg)
+{
+	GIT_UNUSED_ARG(attr);
+	*thread = (pthread_t) CreateThread(NULL, 0, (LPTHREAD_START_ROUTINE)start_routine, arg, 0, NULL);
+	return *thread ? GIT_SUCCESS : GIT_EOSERR;
+}
+
+int pthread_cond_signal(pthread_cond_t *cond)
+{
+    WakeConditionVariable(cond);
+    return 0;
+}
+
+int pthread_cond_wait(pthread_cond_t *GIT_RESTRICT cond,
+                      pthread_mutex_t *GIT_RESTRICT mutex)
+{
+    int ret;
+    ret = SleepConditionVariableCS(cond, mutex, INFINITE);
+    return -(!ret);
+}
+
+int pthread_mutex_lock(pthread_mutex_t *mutex)
+{
+    EnterCriticalSection(mutex);
+    return 0;
+}
+
+int pthread_mutex_unlock(pthread_mutex_t *mutex)
+{
+    LeaveCriticalSection(mutex);
+    return 0;
+}
+
+int pthread_join(pthread_t thread, void **value_ptr)
+{
+    int ret;
+    ret = WaitForSingleObject(thread, INFINITE);
+    if (ret && value_ptr)
+        GetExitCodeThread(thread, (void*) value_ptr);
+    return -(!!ret);
+}
+
+int pthread_cond_broadcast(pthread_cond_t *cond)
+{
+    WakeAllConditionVariable(cond);
+    return 0;
+}
+
+int pthread_mutex_destroy(pthread_mutex_t *mutex)
+{
+    int ret;
+    ret = CloseHandle(mutex);
+    return -(!ret);
+}
+
+int pthread_cond_destroy(pthread_cond_t *GIT_UNUSED(cond))
+{
+	GIT_UNUSED_ARG(cond);
+    return 0;
+}
+
+int pthread_cond_init(pthread_cond_t *GIT_RESTRICT cond,
+                      const pthread_condattr_t *GIT_RESTRICT GIT_UNUSED(condattr))
+{
+	GIT_UNUSED_ARG(condattr);
+    InitializeConditionVariable(cond);
+    return 0;
+}
+
+int pthread_mutex_init(pthread_mutex_t *GIT_RESTRICT mutex,
+                       const pthread_mutexattr_t *GIT_RESTRICT GIT_UNUSED(mutexattr))
+{
+	GIT_UNUSED_ARG(mutexattr);
+    InitializeCriticalSection(mutex);
+    return 0;
+}
+
+int pthread_num_processors_np(void)
+{
+    DWORD_PTR p, s;
+    int n = 0;
+
+    if (GetProcessAffinityMask(GetCurrentProcess(), &p, &s))
+        for (; p; p >>= 1)
+            n += p&1;
+
+    return n ? n : 1;
+}
+
diff --git a/src/win32/pthread.h b/src/win32/pthread.h
new file mode 100644
index 000000000..ff694e303
--- /dev/null
+++ b/src/win32/pthread.h
@@ -0,0 +1,67 @@
+/*
+ * This file is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2,
+ * as published by the Free Software Foundation.
+ *
+ * In addition to the permissions in the GNU General Public License,
+ * the authors give you unlimited permission to link the compiled
+ * version of this file into combinations with other programs,
+ * and to distribute those combinations without any restriction
+ * coming from the use of this file.  (The General Public License
+ * restrictions do apply in other respects; for example, they cover
+ * modification of the file, and distribution when not linked into
+ * a combined executable.)
+ *
+ * This file is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING.  If not, write to
+ * the Free Software Foundation, 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ *
+ *  Original code by Ramiro Polla (Public Domain)
+ */
+
+#ifndef GIT_PTHREAD_H
+#define GIT_PTHREAD_H
+
+#include "../common.h"
+
+#if defined (_MSC_VER)
+#	define GIT_RESTRICT __restrict
+#else
+#	define GIT_RESTRICT __restrict__
+#endif
+
+typedef int pthread_mutexattr_t;
+typedef int pthread_condattr_t;
+typedef int pthread_attr_t;
+typedef CRITICAL_SECTION pthread_mutex_t;
+typedef CONDITION_VARIABLE pthread_cond_t;
+typedef HANDLE pthread_t;
+
+#define PTHREAD_MUTEX_INITIALIZER {(void*)-1};
+
+int pthread_create(pthread_t *GIT_RESTRICT,
+                   const pthread_attr_t *GIT_RESTRICT,
+                   void *(*start_routine)(void*), void *__restrict);
+
+int pthread_join(pthread_t, void **);
+
+int pthread_mutex_init(pthread_mutex_t *GIT_RESTRICT, const pthread_mutexattr_t *GIT_RESTRICT);
+int pthread_mutex_destroy(pthread_mutex_t *);
+int pthread_mutex_lock(pthread_mutex_t *);
+int pthread_mutex_unlock(pthread_mutex_t *);
+
+int pthread_cond_init(pthread_cond_t *GIT_RESTRICT, const pthread_condattr_t *GIT_RESTRICT);
+int pthread_cond_destroy(pthread_cond_t *);
+int pthread_cond_broadcast(pthread_cond_t *);
+int pthread_cond_signal(pthread_cond_t *);
+int pthread_cond_wait(pthread_cond_t *GIT_RESTRICT, pthread_mutex_t *GIT_RESTRICT);
+
+int pthread_num_processors_np(void);
+
+#endif
\ No newline at end of file