Revert "More pthreads cleanup."

This reverts commit 2a1bb4e64677b9abbc17173c79768ed494565047

Change-Id: Ia443d0748015c8e9fc3121e40e68258616767b51
diff --git a/libc/private/ErrnoRestorer.h b/libc/private/ErrnoRestorer.h
deleted file mode 100644
index ed6ab62..0000000
--- a/libc/private/ErrnoRestorer.h
+++ /dev/null
@@ -1,43 +0,0 @@
-/*
- * Copyright (C) 2013 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#ifndef ERRNO_RESTORER_H
-#define ERRNO_RESTORER_H
-
-#include <errno.h>
-
-class ErrnoRestorer {
- public:
-  explicit ErrnoRestorer() : saved_errno_(errno) {
-  }
-
-  ~ErrnoRestorer() {
-    errno = saved_errno_;
-  }
-
-  void override(int new_errno) {
-    saved_errno_ = new_errno;
-  }
-
- private:
-  int saved_errno_;
-
-  // Disallow copy and assignment.
-  ErrnoRestorer(const ErrnoRestorer&);
-  void operator=(const ErrnoRestorer&);
-};
-
-#endif // ERRNO_RESTORER_H
diff --git a/libc/private/ThreadLocalBuffer.h b/libc/private/ThreadLocalBuffer.h
index 703acd6..1c5e3f4 100644
--- a/libc/private/ThreadLocalBuffer.h
+++ b/libc/private/ThreadLocalBuffer.h
@@ -37,17 +37,18 @@
 // TODO: move __cxa_guard_acquire and __cxa_guard_release into libc.
 
 #define GLOBAL_INIT_THREAD_LOCAL_BUFFER(name) \
+  static pthread_once_t __bionic_tls_ ## name ## _once; \
   static pthread_key_t __bionic_tls_ ## name ## _key; \
   static void __bionic_tls_ ## name ## _key_destroy(void* buffer) { \
     free(buffer); \
   } \
-  /* Run automatically when libc.so is opened by the dynamic linker. */ \
-  __attribute__((constructor)) static void __bionic_tls_ ## name ## _key_init() { \
+  static void __bionic_tls_ ## name ## _key_init() { \
     pthread_key_create(&__bionic_tls_ ## name ## _key, __bionic_tls_ ## name ## _key_destroy); \
   }
 
 // Leaves "name_tls_buffer" and "name_tls_buffer_size" defined and initialized.
 #define LOCAL_INIT_THREAD_LOCAL_BUFFER(type, name, byte_count) \
+  pthread_once(&__bionic_tls_ ## name ## _once, __bionic_tls_ ## name ## _key_init); \
   type name ## _tls_buffer = \
       reinterpret_cast<type>(pthread_getspecific(__bionic_tls_ ## name ## _key)); \
   if (name ## _tls_buffer == NULL) { \
diff --git a/libc/private/bionic_futex.h b/libc/private/bionic_futex.h
index 6c7fdbe..eb49fb7 100644
--- a/libc/private/bionic_futex.h
+++ b/libc/private/bionic_futex.h
@@ -30,8 +30,6 @@
 
 #include <linux/futex.h>
 
-__BEGIN_DECLS
-
 extern int __futex_wait(volatile void *ftx, int val, const struct timespec *timeout);
 extern int __futex_wake(volatile void *ftx, int count);
 
@@ -56,6 +54,4 @@
 extern int  __futex_wake_ex(volatile void *ftx, int pshared, int val);
 extern int  __futex_wait_ex(volatile void *ftx, int pshared, int val, const struct timespec *timeout);
 
-__END_DECLS
-
 #endif /* _BIONIC_FUTEX_H */
diff --git a/libc/private/bionic_tls.h b/libc/private/bionic_tls.h
index 846eb84..edf878f 100644
--- a/libc/private/bionic_tls.h
+++ b/libc/private/bionic_tls.h
@@ -43,40 +43,28 @@
  ** pre-allocated slot directly for performance reason).
  **/
 
+/* Maximum number of elements in the TLS array. */
+#define BIONIC_TLS_SLOTS            64
+
 /* Well-known TLS slots. What data goes in which slot is arbitrary unless otherwise noted. */
 enum {
   TLS_SLOT_SELF = 0, /* The kernel requires this specific slot for x86. */
   TLS_SLOT_THREAD_ID,
   TLS_SLOT_ERRNO,
-
-  /* These two aren't used by bionic itself, but allow the graphics code to
-   * access TLS directly rather than using the pthread API. */
   TLS_SLOT_OPENGL_API = 3,
   TLS_SLOT_OPENGL = 4,
-
-  /* This slot is only used to pass information from the dynamic linker to
-   * libc.so when the C library is loaded in to memory. The C runtime init
-   * function will then clear it. Since its use is extremely temporary,
-   * we reuse an existing location that isn't needed during libc startup. */
-  TLS_SLOT_BIONIC_PREINIT = TLS_SLOT_OPENGL_API,
-
   TLS_SLOT_STACK_GUARD = 5, /* GCC requires this specific slot for x86. */
   TLS_SLOT_DLERROR,
 
   TLS_SLOT_FIRST_USER_SLOT /* Must come last! */
 };
 
-/*
- * Maximum number of elements in the TLS array.
- * POSIX says this must be at least 128, but Android has traditionally had only 64, minus those
- * ones used internally by bionic itself.
- * There are two kinds of slot used internally by bionic --- there are the well-known slots
- * enumerated above, and then there are those that are allocated during startup by calls to
- * pthread_key_create; grep for GLOBAL_INIT_THREAD_LOCAL_BUFFER to find those. We need to manually
- * maintain that second number, but pthread_test will fail if we forget.
+/* This slot is only used to pass information from the dynamic linker to
+ * libc.so when the C library is loaded in to memory. The C runtime init
+ * function will then clear it. Since its use is extremely temporary,
+ * we reuse an existing location that isn't needed during libc startup.
  */
-#define GLOBAL_INIT_THREAD_LOCAL_BUFFER_COUNT 4
-#define BIONIC_TLS_SLOTS (64 + TLS_SLOT_FIRST_USER_SLOT + GLOBAL_INIT_THREAD_LOCAL_BUFFER_COUNT)
+#define  TLS_SLOT_BIONIC_PREINIT    TLS_SLOT_OPENGL_API
 
 /* set the Thread Local Storage, must contain at least BIONIC_TLS_SLOTS pointers */
 extern void __init_tls(void**  tls, void*  thread_info);