refactor: `src` is now `src/libgit2`

Adding an additional hierarchy allows us to split out utility functions.

1 files changed, 479 insertions, 0 deletions

diff --git a/src/libgit2/thread.h b/src/libgit2/thread.h
new file mode 100644
index 000000000..82eb7fcab
--- /dev/null
+++ b/src/libgit2/thread.h
@@ -0,0 +1,479 @@
+/*
+ * Copyright (C) the libgit2 contributors. All rights reserved.
+ *
+ * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * a Linking Exception. For full terms see the included COPYING file.
+ */
+#ifndef INCLUDE_thread_h__
+#define INCLUDE_thread_h__
+
+#if defined(GIT_THREADS)
+
+#if defined(__clang__)
+
+# if (__clang_major__ < 3 || (__clang_major__ == 3 && __clang_minor__ < 1))
+#  error Atomic primitives do not exist on this version of clang; configure libgit2 with -DUSE_THREADS=OFF
+# else
+#  define GIT_BUILTIN_ATOMIC
+# endif
+
+#elif defined(__GNUC__)
+
+# if (__GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 1))
+#  error Atomic primitives do not exist on this version of gcc; configure libgit2 with -DUSE_THREADS=OFF
+# elif (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 7))
+#  define GIT_BUILTIN_ATOMIC
+# else
+#  define GIT_BUILTIN_SYNC
+# endif
+
+#endif
+
+#endif /* GIT_THREADS */
+
+/* Common operations even if threading has been disabled */
+typedef struct {
+#if defined(GIT_WIN32)
+	volatile long val;
+#else
+	volatile int val;
+#endif
+} git_atomic32;
+
+#ifdef GIT_ARCH_64
+
+typedef struct {
+#if defined(GIT_WIN32)
+	volatile __int64 val;
+#else
+	volatile int64_t val;
+#endif
+} git_atomic64;
+
+typedef git_atomic64 git_atomic_ssize;
+
+#define git_atomic_ssize_set git_atomic64_set
+#define git_atomic_ssize_add git_atomic64_add
+#define git_atomic_ssize_get git_atomic64_get
+
+#else
+
+typedef git_atomic32 git_atomic_ssize;
+
+#define git_atomic_ssize_set git_atomic32_set
+#define git_atomic_ssize_add git_atomic32_add
+#define git_atomic_ssize_get git_atomic32_get
+
+#endif
+
+#ifdef GIT_THREADS
+
+#ifdef GIT_WIN32
+#   include "win32/thread.h"
+#else
+#   include "unix/pthread.h"
+#endif
+
+/*
+ * Atomically sets the contents of *a to be val.
+ */
+GIT_INLINE(void) git_atomic32_set(git_atomic32 *a, int val)
+{
+#if defined(GIT_WIN32)
+	InterlockedExchange(&a->val, (LONG)val);
+#elif defined(GIT_BUILTIN_ATOMIC)
+	__atomic_store_n(&a->val, val, __ATOMIC_SEQ_CST);
+#elif defined(GIT_BUILTIN_SYNC)
+	__sync_lock_test_and_set(&a->val, val);
+#else
+#	error "Unsupported architecture for atomic operations"
+#endif
+}
+
+/*
+ * Atomically increments the contents of *a by 1, and stores the result back into *a.
+ * @return the result of the operation.
+ */
+GIT_INLINE(int) git_atomic32_inc(git_atomic32 *a)
+{
+#if defined(GIT_WIN32)
+	return InterlockedIncrement(&a->val);
+#elif defined(GIT_BUILTIN_ATOMIC)
+	return __atomic_add_fetch(&a->val, 1, __ATOMIC_SEQ_CST);
+#elif defined(GIT_BUILTIN_SYNC)
+	return __sync_add_and_fetch(&a->val, 1);
+#else
+#	error "Unsupported architecture for atomic operations"
+#endif
+}
+
+/*
+ * Atomically adds the contents of *a and addend, and stores the result back into *a.
+ * @return the result of the operation.
+ */
+GIT_INLINE(int) git_atomic32_add(git_atomic32 *a, int32_t addend)
+{
+#if defined(GIT_WIN32)
+	return InterlockedAdd(&a->val, addend);
+#elif defined(GIT_BUILTIN_ATOMIC)
+	return __atomic_add_fetch(&a->val, addend, __ATOMIC_SEQ_CST);
+#elif defined(GIT_BUILTIN_SYNC)
+	return __sync_add_and_fetch(&a->val, addend);
+#else
+#	error "Unsupported architecture for atomic operations"
+#endif
+}
+
+/*
+ * Atomically decrements the contents of *a by 1, and stores the result back into *a.
+ * @return the result of the operation.
+ */
+GIT_INLINE(int) git_atomic32_dec(git_atomic32 *a)
+{
+#if defined(GIT_WIN32)
+	return InterlockedDecrement(&a->val);
+#elif defined(GIT_BUILTIN_ATOMIC)
+	return __atomic_sub_fetch(&a->val, 1, __ATOMIC_SEQ_CST);
+#elif defined(GIT_BUILTIN_SYNC)
+	return __sync_sub_and_fetch(&a->val, 1);
+#else
+#	error "Unsupported architecture for atomic operations"
+#endif
+}
+
+/*
+ * Atomically gets the contents of *a.
+ * @return the contents of *a.
+ */
+GIT_INLINE(int) git_atomic32_get(git_atomic32 *a)
+{
+#if defined(GIT_WIN32)
+	return (int)InterlockedCompareExchange(&a->val, 0, 0);
+#elif defined(GIT_BUILTIN_ATOMIC)
+	return __atomic_load_n(&a->val, __ATOMIC_SEQ_CST);
+#elif defined(GIT_BUILTIN_SYNC)
+	return __sync_val_compare_and_swap(&a->val, 0, 0);
+#else
+#	error "Unsupported architecture for atomic operations"
+#endif
+}
+
+GIT_INLINE(void *) git_atomic__compare_and_swap(
+	void * volatile *ptr, void *oldval, void *newval)
+{
+#if defined(GIT_WIN32)
+	return InterlockedCompareExchangePointer((volatile PVOID *)ptr, newval, oldval);
+#elif defined(GIT_BUILTIN_ATOMIC)
+	void *foundval = oldval;
+	__atomic_compare_exchange(ptr, &foundval, &newval, false, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST);
+	return foundval;
+#elif defined(GIT_BUILTIN_SYNC)
+	return __sync_val_compare_and_swap(ptr, oldval, newval);
+#else
+#	error "Unsupported architecture for atomic operations"
+#endif
+}
+
+GIT_INLINE(volatile void *) git_atomic__swap(
+	void * volatile *ptr, void *newval)
+{
+#if defined(GIT_WIN32)
+	return InterlockedExchangePointer(ptr, newval);
+#elif defined(GIT_BUILTIN_ATOMIC)
+	void * volatile foundval = NULL;
+	__atomic_exchange(ptr, &newval, &foundval, __ATOMIC_SEQ_CST);
+	return foundval;
+#elif defined(GIT_BUILTIN_SYNC)
+	return (volatile void *)__sync_lock_test_and_set(ptr, newval);
+#else
+#	error "Unsupported architecture for atomic operations"
+#endif
+}
+
+GIT_INLINE(volatile void *) git_atomic__load(void * volatile *ptr)
+{
+#if defined(GIT_WIN32)
+	void *newval = NULL, *oldval = NULL;
+	return (volatile void *)InterlockedCompareExchangePointer((volatile PVOID *)ptr, newval, oldval);
+#elif defined(GIT_BUILTIN_ATOMIC)
+	return (volatile void *)__atomic_load_n(ptr, __ATOMIC_SEQ_CST);
+#elif defined(GIT_BUILTIN_SYNC)
+	return (volatile void *)__sync_val_compare_and_swap(ptr, 0, 0);
+#else
+#	error "Unsupported architecture for atomic operations"
+#endif
+}
+
+#ifdef GIT_ARCH_64
+
+/*
+ * Atomically adds the contents of *a and addend, and stores the result back into *a.
+ * @return the result of the operation.
+ */
+GIT_INLINE(int64_t) git_atomic64_add(git_atomic64 *a, int64_t addend)
+{
+#if defined(GIT_WIN32)
+	return InterlockedAdd64(&a->val, addend);
+#elif defined(GIT_BUILTIN_ATOMIC)
+	return __atomic_add_fetch(&a->val, addend, __ATOMIC_SEQ_CST);
+#elif defined(GIT_BUILTIN_SYNC)
+	return __sync_add_and_fetch(&a->val, addend);
+#else
+#	error "Unsupported architecture for atomic operations"
+#endif
+}
+
+/*
+ * Atomically sets the contents of *a to be val.
+ */
+GIT_INLINE(void) git_atomic64_set(git_atomic64 *a, int64_t val)
+{
+#if defined(GIT_WIN32)
+	InterlockedExchange64(&a->val, val);
+#elif defined(GIT_BUILTIN_ATOMIC)
+	__atomic_store_n(&a->val, val, __ATOMIC_SEQ_CST);
+#elif defined(GIT_BUILTIN_SYNC)
+	__sync_lock_test_and_set(&a->val, val);
+#else
+#	error "Unsupported architecture for atomic operations"
+#endif
+}
+
+/*
+ * Atomically gets the contents of *a.
+ * @return the contents of *a.
+ */
+GIT_INLINE(int64_t) git_atomic64_get(git_atomic64 *a)
+{
+#if defined(GIT_WIN32)
+	return (int64_t)InterlockedCompareExchange64(&a->val, 0, 0);
+#elif defined(GIT_BUILTIN_ATOMIC)
+	return __atomic_load_n(&a->val, __ATOMIC_SEQ_CST);
+#elif defined(GIT_BUILTIN_SYNC)
+	return __sync_val_compare_and_swap(&a->val, 0, 0);
+#else
+#	error "Unsupported architecture for atomic operations"
+#endif
+}
+
+#endif
+
+#else
+
+#define git_threads_global_init git__noop
+
+#define git_thread unsigned int
+#define git_thread_create(thread, start_routine, arg) git__noop()
+#define git_thread_join(id, status) git__noop()
+
+/* Pthreads Mutex */
+#define git_mutex unsigned int
+#define git_mutex_init(a)	git__noop()
+#define git_mutex_init(a)	git__noop()
+#define git_mutex_lock(a)	git__noop()
+#define git_mutex_unlock(a)	git__noop()
+#define git_mutex_free(a)	git__noop()
+
+/* Pthreads condition vars */
+#define git_cond unsigned int
+#define git_cond_init(c)	git__noop()
+#define git_cond_free(c)	git__noop()
+#define git_cond_wait(c, l)	git__noop()
+#define git_cond_signal(c)	git__noop()
+#define git_cond_broadcast(c)	git__noop()
+
+/* Pthreads rwlock */
+#define git_rwlock unsigned int
+#define git_rwlock_init(a)	git__noop()
+#define git_rwlock_rdlock(a)	git__noop()
+#define git_rwlock_rdunlock(a)	git__noop()
+#define git_rwlock_wrlock(a)	git__noop()
+#define git_rwlock_wrunlock(a)	git__noop()
+#define git_rwlock_free(a)	git__noop()
+#define GIT_RWLOCK_STATIC_INIT	0
+
+
+GIT_INLINE(void) git_atomic32_set(git_atomic32 *a, int val)
+{
+	a->val = val;
+}
+
+GIT_INLINE(int) git_atomic32_inc(git_atomic32 *a)
+{
+	return ++a->val;
+}
+
+GIT_INLINE(int) git_atomic32_add(git_atomic32 *a, int32_t addend)
+{
+	a->val += addend;
+	return a->val;
+}
+
+GIT_INLINE(int) git_atomic32_dec(git_atomic32 *a)
+{
+	return --a->val;
+}
+
+GIT_INLINE(int) git_atomic32_get(git_atomic32 *a)
+{
+	return (int)a->val;
+}
+
+GIT_INLINE(void *) git_atomic__compare_and_swap(
+	void * volatile *ptr, void *oldval, void *newval)
+{
+	void *foundval = *ptr;
+	if (foundval == oldval)
+		*ptr = newval;
+	return foundval;
+}
+
+GIT_INLINE(volatile void *) git_atomic__swap(
+	void * volatile *ptr, void *newval)
+{
+	volatile void *old = *ptr;
+	*ptr = newval;
+	return old;
+}
+
+GIT_INLINE(volatile void *) git_atomic__load(void * volatile *ptr)
+{
+	return *ptr;
+}
+
+#ifdef GIT_ARCH_64
+
+GIT_INLINE(int64_t) git_atomic64_add(git_atomic64 *a, int64_t addend)
+{
+	a->val += addend;
+	return a->val;
+}
+
+GIT_INLINE(void) git_atomic64_set(git_atomic64 *a, int64_t val)
+{
+	a->val = val;
+}
+
+GIT_INLINE(int64_t) git_atomic64_get(git_atomic64 *a)
+{
+	return (int64_t)a->val;
+}
+
+#endif
+
+#endif
+
+/*
+ * Atomically replace the contents of *ptr (if they are equal to oldval) with
+ * newval. ptr must point to a pointer or a value that is the same size as a
+ * pointer. This is semantically compatible with:
+ *
+ *   #define git_atomic_compare_and_swap(ptr, oldval, newval) \
+ *   ({                                                       \
+ *       void *foundval = *ptr;                               \
+ *       if (foundval == oldval)                              \
+ *           *ptr = newval;                                   \
+ *       foundval;                                            \
+ *   })
+ *
+ * @return the original contents of *ptr.
+ */
+#define git_atomic_compare_and_swap(ptr, oldval, newval) \
+	git_atomic__compare_and_swap((void * volatile *)ptr, oldval, newval)
+
+/*
+ * Atomically replace the contents of v with newval. v must be the same size as
+ * a pointer. This is semantically compatible with:
+ *
+ *   #define git_atomic_swap(v, newval) \
+ *   ({                                 \
+ *       volatile void *old = v;        \
+ *       v = newval;                    \
+ *       old;                           \
+ *   })
+ *
+ * @return the original contents of v.
+ */
+#define git_atomic_swap(v, newval) \
+	(void *)git_atomic__swap((void * volatile *)&(v), newval)
+
+/*
+ * Atomically reads the contents of v. v must be the same size as a pointer.
+ * This is semantically compatible with:
+ *
+ *   #define git_atomic_load(v) v
+ *
+ * @return the contents of v.
+ */
+#define git_atomic_load(v) \
+	(void *)git_atomic__load((void * volatile *)&(v))
+
+#if defined(GIT_THREADS)
+
+# if defined(GIT_WIN32)
+#  define GIT_MEMORY_BARRIER MemoryBarrier()
+# elif defined(GIT_BUILTIN_ATOMIC)
+#  define GIT_MEMORY_BARRIER __atomic_thread_fence(__ATOMIC_SEQ_CST)
+# elif defined(GIT_BUILTIN_SYNC)
+#  define GIT_MEMORY_BARRIER __sync_synchronize()
+# endif
+
+#else
+
+# define GIT_MEMORY_BARRIER /* noop */
+
+#endif
+
+/* Thread-local data */
+
+#if !defined(GIT_THREADS)
+# define git_tlsdata_key int
+#elif defined(GIT_WIN32)
+# define git_tlsdata_key DWORD
+#elif defined(_POSIX_THREADS)
+# define git_tlsdata_key pthread_key_t
+#else
+# error unknown threading model
+#endif
+
+/**
+ * Create a thread-local data key.  The destroy function will be
+ * called upon thread exit.  On some platforms, it may be called
+ * when all threads have deleted their keys.
+ *
+ * Note that the tlsdata functions do not set an error message on
+ * failure; this is because the error handling in libgit2 is itself
+ * handled by thread-local data storage.
+ *
+ * @param key the tlsdata key
+ * @param destroy_fn function pointer called upon thread exit
+ * @return 0 on success, non-zero on failure
+ */
+int git_tlsdata_init(git_tlsdata_key *key, void (GIT_SYSTEM_CALL *destroy_fn)(void *));
+
+/**
+ * Set a the thread-local value for the given key.
+ *
+ * @param key the tlsdata key to store data on
+ * @param value the pointer to store
+ * @return 0 on success, non-zero on failure
+ */
+int git_tlsdata_set(git_tlsdata_key key, void *value);
+
+/**
+ * Get the thread-local value for the given key.
+ *
+ * @param key the tlsdata key to retrieve the value of
+ * @return the pointer stored with git_tlsdata_set
+ */
+void *git_tlsdata_get(git_tlsdata_key key);
+
+/**
+ * Delete the given thread-local key.
+ *
+ * @param key the tlsdata key to dispose
+ * @return 0 on success, non-zero on failure
+ */
+int git_tlsdata_dispose(git_tlsdata_key key);
+
+#endif