Revert r249929 ("Split <string.h> out of <cstring>").

This change caused problems when building code like povray that:
a) uses 'using namespace std;'
b) is built on an environment where the C library provides the "wrong"
   (non-const-correct) interface for the str* functions
c) makes an unqualified call to one of those str* functions

A patch is out for review to add a facility to fix this (and to give the
correct signatures for these functions whenever possible, even when the C
library does not do so). This revert is expected to be temporary.

llvm-svn: 251665

2 files changed, 18 insertions, 86 deletions

diff --git a/libcxx/include/cstring b/libcxx/include/cstring
index 5e1837202be..d60b9923c6c 100644
--- a/libcxx/include/cstring
+++ b/libcxx/include/cstring
@@ -78,42 +78,37 @@ using ::strcmp;
 using ::strncmp;
 using ::strcoll;
 using ::strxfrm;
-using ::strcspn;
-using ::strspn;
-#ifndef _LIBCPP_HAS_NO_THREAD_UNSAFE_C_FUNCTIONS
-using ::strtok;
-#endif
-using ::memset;
-using ::strerror;
-using ::strlen;
 
-// MSVCRT, GNU libc and its derivates already have the correct prototype in
-// <string.h> if __cplusplus is defined. This macro can be defined by users if
-// their C library provides the right signature.
-#if defined(__GLIBC__) || defined(_LIBCPP_MSVCRT) || defined(__sun__) || \
-    defined(_STRING_H_CPLUSPLUS_98_CONFORMANCE_)
-#define _LIBCPP_STRING_H_HAS_CONST_OVERLOADS
-#endif
+using ::memchr;
 
-#ifdef _LIBCPP_STRING_H_HAS_CONST_OVERLOADS
 using ::strchr;
+
+using ::strcspn;
+
 using ::strpbrk;
+
 using ::strrchr;
-using ::memchr;
+
+using ::strspn;
+
 using ::strstr;
-#else
-inline _LIBCPP_INLINE_VISIBILITY const char* strchr(const char* __s, int __c) {return ::strchr(__s, __c);}
+
+// MSVCRT, GNU libc and its derivates already have the correct prototype in <string.h> #ifdef __cplusplus
+#if !defined(__GLIBC__) && !defined(_LIBCPP_MSVCRT) && !defined(__sun__) && !defined(_STRING_H_CPLUSPLUS_98_CONFORMANCE_)
 inline _LIBCPP_INLINE_VISIBILITY       char* strchr(      char* __s, int __c) {return ::strchr(__s, __c);}
-inline _LIBCPP_INLINE_VISIBILITY const char* strpbrk(const char* __s1, const char* __s2) {return ::strpbrk(__s1, __s2);}
 inline _LIBCPP_INLINE_VISIBILITY       char* strpbrk(      char* __s1, const char* __s2) {return ::strpbrk(__s1, __s2);}
-inline _LIBCPP_INLINE_VISIBILITY const char* strrchr(const char* __s, int __c) {return ::strrchr(__s, __c);}
 inline _LIBCPP_INLINE_VISIBILITY       char* strrchr(      char* __s, int __c) {return ::strrchr(__s, __c);}
-inline _LIBCPP_INLINE_VISIBILITY const void* memchr(const void* __s, int __c, size_t __n) {return ::memchr(__s, __c, __n);}
 inline _LIBCPP_INLINE_VISIBILITY       void* memchr(      void* __s, int __c, size_t __n) {return ::memchr(__s, __c, __n);}
-inline _LIBCPP_INLINE_VISIBILITY const char* strstr(const char* __s1, const char* __s2) {return ::strstr(__s1, __s2);}
 inline _LIBCPP_INLINE_VISIBILITY       char* strstr(      char* __s1, const char* __s2) {return ::strstr(__s1, __s2);}
 #endif
 
+#ifndef _LIBCPP_HAS_NO_THREAD_UNSAFE_C_FUNCTIONS
+using ::strtok;
+#endif
+using ::memset;
+using ::strerror;
+using ::strlen;
+
 _LIBCPP_END_NAMESPACE_STD
 
 #endif  // _LIBCPP_CSTRING
diff --git a/libcxx/include/string.h b/libcxx/include/string.h
deleted file mode 100644
index c3b1e46ec6d..00000000000
--- a/libcxx/include/string.h
+++ /dev/null
@@ -1,63 +0,0 @@
-// -*- C++ -*-
-//===--------------------------- string.h ---------------------------------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef _LIBCPP_STRING_H
-#define _LIBCPP_STRING_H
-
-/*
-    string.h synopsis
-
-Macros:
-
-    NULL
-
-Types:
-
-    size_t
-
-void* memcpy(void* restrict s1, const void* restrict s2, size_t n);
-void* memmove(void* s1, const void* s2, size_t n);
-char* strcpy (char* restrict s1, const char* restrict s2);
-char* strncpy(char* restrict s1, const char* restrict s2, size_t n);
-char* strcat (char* restrict s1, const char* restrict s2);
-char* strncat(char* restrict s1, const char* restrict s2, size_t n);
-int memcmp(const void* s1, const void* s2, size_t n);
-int strcmp (const char* s1, const char* s2);
-int strncmp(const char* s1, const char* s2, size_t n);
-int strcoll(const char* s1, const char* s2);
-size_t strxfrm(char* restrict s1, const char* restrict s2, size_t n);
-const void* memchr(const void* s, int c, size_t n);
-      void* memchr(      void* s, int c, size_t n);
-const char* strchr(const char* s, int c);
-      char* strchr(      char* s, int c);
-size_t strcspn(const char* s1, const char* s2);
-const char* strpbrk(const char* s1, const char* s2);
-      char* strpbrk(      char* s1, const char* s2);
-const char* strrchr(const char* s, int c);
-      char* strrchr(      char* s, int c);
-size_t strspn(const char* s1, const char* s2);
-const char* strstr(const char* s1, const char* s2);
-      char* strstr(      char* s1, const char* s2);
-char* strtok(char* restrict s1, const char* restrict s2);
-void* memset(void* s, int c, size_t n);
-char* strerror(int errnum);
-size_t strlen(const char* s);
-
-*/
-
-#include <__config>
-
-#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
-#pragma GCC system_header
-#endif
-
-#include_next <string.h>
-
-#endif  // _LIBCPP_STRING_H