auto import from //depot/cupcake/@135843
diff --git a/libc/private/thread_private.h b/libc/private/thread_private.h
new file mode 100644
index 0000000..c03f0ab
--- /dev/null
+++ b/libc/private/thread_private.h
@@ -0,0 +1,162 @@
+/* $OpenBSD: thread_private.h,v 1.18 2006/02/22 07:16:31 otto Exp $ */
+
+/* PUBLIC DOMAIN: No Rights Reserved. Marco S Hyman <marc@snafu.org> */
+
+#ifndef _THREAD_PRIVATE_H_
+#define _THREAD_PRIVATE_H_
+
+#include <pthread.h>
+
+/*
+ * This file defines the thread library interface to libc. Thread
+ * libraries must implement the functions described here for proper
+ * inter-operation with libc. libc contains weak versions of the
+ * described functions for operation in a non-threaded environment.
+ */
+
+/*
+ * This variable is 0 until a second thread is created.
+ */
+extern int __isthreaded;
+
+/*
+ * Weak symbols are used in libc so that the thread library can
+ * efficiently wrap libc functions.
+ *
+ * Use WEAK_NAME(n) to get a libc-private name for n (_weak_n),
+ * WEAK_ALIAS(n) to generate the weak symbol n pointing to _weak_n,
+ * WEAK_PROTOTYPE(n) to generate a prototype for _weak_n (based on n).
+ */
+#define WEAK_NAME(name) __CONCAT(_weak_,name)
+#define WEAK_ALIAS(name) __weak_alias(name, WEAK_NAME(name))
+#ifdef __GNUC__
+#define WEAK_PROTOTYPE(name) __typeof__(name) WEAK_NAME(name)
+#else
+#define WEAK_PROTOTYPE(name) /* typeof() only in gcc */
+#endif
+
+/*
+ * helper macro to make unique names in the thread namespace
+ */
+#define __THREAD_NAME(name) __CONCAT(_thread_tagname_,name)
+
+struct __thread_private_tag_t {
+ pthread_mutex_t _private_lock;
+ pthread_key_t _private_key;
+};
+
+#define _THREAD_PRIVATE_MUTEX(name) \
+ static struct __thread_private_tag_t __THREAD_NAME(name) = { PTHREAD_MUTEX_INITIALIZER, -1 }
+#define _THREAD_PRIVATE_MUTEX_LOCK(name) \
+ pthread_mutex_lock( &__THREAD_NAME(name)._private_lock )
+#define _THREAD_PRIVATE_MUTEX_UNLOCK(name) \
+ pthread_mutex_unlock( &__THREAD_NAME(name)._private_lock )
+
+#define _THREAD_PRIVATE_KEY(name) \
+ static struct __thread_private_tag_t __THREAD_NAME(name) = { PTHREAD_MUTEX_INITIALIZER, -1 }
+
+extern void* __bionic_thread_private_storage( struct __thread_private_tag_t* ptag, void* storage, size_t objsize, void* error );
+
+#define _THREAD_PRIVATE(name, storage, error) \
+ __bionic_thread_private_storage( &__THREAD_NAME(name), &(storage),sizeof(storage), error)
+
+#if 0
+/*
+ * helper functions that exist as (weak) null functions in libc and
+ * (strong) functions in the thread library. These functions:
+ *
+ * _thread_tag_lock:
+ * lock the mutex associated with the given tag. If the given
+ * tag is NULL a tag is first allocated.
+ *
+ * _thread_tag_unlock:
+ * unlock the mutex associated with the given tag. If the given
+ * tag is NULL a tag is first allocated.
+ *
+ * _thread_tag_storage:
+ * return a pointer to per thread instance of data associated
+ * with the given tag. If the given tag is NULL a tag is first
+ * allocated.
+ */
+void _thread_tag_lock(void **);
+void _thread_tag_unlock(void **);
+void *_thread_tag_storage(void **, void *, size_t, void *);
+
+/*
+ * Macros used in libc to access thread mutex, keys, and per thread storage.
+ * _THREAD_PRIVATE_KEY and _THREAD_PRIVATE_MUTEX are different macros for
+ * historical reasons. They do the same thing, define a static variable
+ * keyed by 'name' that identifies a mutex and a key to identify per thread
+ * data.
+ */
+#define _THREAD_PRIVATE_KEY(name) \
+ static void *__THREAD_NAME(name)
+#define _THREAD_PRIVATE_MUTEX(name) \
+ static void *__THREAD_NAME(name)
+#define _THREAD_PRIVATE_MUTEX_LOCK(name) \
+ _thread_tag_lock(&(__THREAD_NAME(name)))
+#define _THREAD_PRIVATE_MUTEX_UNLOCK(name) \
+ _thread_tag_unlock(&(__THREAD_NAME(name)))
+#define _THREAD_PRIVATE(keyname, storage, error) \
+ _thread_tag_storage(&(__THREAD_NAME(keyname)), &(storage), \
+ sizeof (storage), error)
+/*
+ * Resolver code is special cased in that it uses global keys.
+ */
+extern void *__THREAD_NAME(_res);
+extern void *__THREAD_NAME(_res_ext);
+extern void *__THREAD_NAME(serv_mutex);
+#endif
+
+/*
+ * File descriptor locking definitions.
+ */
+#define FD_READ 0x1
+#define FD_WRITE 0x2
+#define FD_RDWR (FD_READ | FD_WRITE)
+
+struct timespec;
+int _thread_fd_lock(int, int, struct timespec *);
+void _thread_fd_unlock(int, int);
+
+/*
+ * Macros are used in libc code for historical (debug) reasons.
+ * Define them here.
+ */
+#define _FD_LOCK(_fd,_type,_ts) _thread_fd_lock(_fd, _type, _ts)
+#define _FD_UNLOCK(_fd,_type) _thread_fd_unlock(_fd, _type)
+
+
+/*
+ * malloc lock/unlock prototypes and definitions
+ */
+void _thread_malloc_init(void);
+void _thread_malloc_lock(void);
+void _thread_malloc_unlock(void);
+
+#define _MALLOC_LOCK() do { \
+ if (__isthreaded) \
+ _thread_malloc_lock(); \
+ } while (0)
+#define _MALLOC_UNLOCK() do { \
+ if (__isthreaded) \
+ _thread_malloc_unlock();\
+ } while (0)
+#define _MALLOC_LOCK_INIT() do { \
+ if (__isthreaded) \
+ _thread_malloc_init();\
+ } while (0)
+
+void _thread_atexit_lock(void);
+void _thread_atexit_unlock(void);
+
+#define _ATEXIT_LOCK() do { \
+ if (__isthreaded) \
+ _thread_atexit_lock(); \
+ } while (0)
+#define _ATEXIT_UNLOCK() do { \
+ if (__isthreaded) \
+ _thread_atexit_unlock();\
+ } while (0)
+
+#endif /* _THREAD_PRIVATE_H_ */