Feature test macros overhaul: stdlib.h

Throughout, simplify the C99/C11 conditionals, and replace
__STRICT_ANSI__ with the proper internal POSIX macros.  The _*_r
reentrant functions need not be guarded (and most haven't been) because
such names in the global scope are reserved to the implementation.

atoff is unique to newlib.

dtoa is not actually exported (_dtoa_r is used internally), is
nonstandard, and the declaration conflicts with the code included in
MySQL, NSPR, and SpiderMonkey.

mktemp was removed in POSIX.1-2001.

The qsort_r declarations are reordered so that the GNU version retains
precedence.

Signed-off-by: Yaakov Selkowitz <yselkowi@redhat.com>

3 files changed, 55 insertions, 46 deletions

diff --git a/newlib/libc/include/stdlib.h b/newlib/libc/include/stdlib.h
index fd6315b06..b0856fa08 100644
--- a/newlib/libc/include/stdlib.h
+++ b/newlib/libc/include/stdlib.h
@@ -40,9 +40,7 @@ typedef struct
   long rem; /* remainder */
 } ldiv_t;
 
-#if !defined(__STRICT_ANSI__) || \
-  (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) || \
-  (defined(__cplusplus) && __cplusplus >= 201103L)
+#if __ISO_C_VISIBLE >= 1999
 typedef struct
 {
   long long int quot; /* quotient */
@@ -68,7 +66,7 @@ _VOID	_EXFUN(abort,(_VOID) _ATTRIBUTE ((__noreturn__)));
 int	_EXFUN(abs,(int));
 int	_EXFUN(atexit,(_VOID (*__func)(_VOID)));
 double	_EXFUN(atof,(const char *__nptr));
-#ifndef __STRICT_ANSI__
+#if __MISC_VISIBLE
 float	_EXFUN(atoff,(const char *__nptr));
 #endif
 int	_EXFUN(atoi,(const char *__nptr));
@@ -88,7 +86,7 @@ char *  _EXFUN(getenv,(const char *__string));
 char *	_EXFUN(_getenv_r,(struct _reent *, const char *__string));
 char *	_EXFUN(_findenv,(_CONST char *, int *));
 char *	_EXFUN(_findenv_r,(struct _reent *, _CONST char *, int *));
-#ifndef __STRICT_ANSI__
+#if __POSIX_VISIBLE >= 200809
 extern char *suboptarg;			/* getsubopt(3) external variable */
 int	_EXFUN(getsubopt,(char **, char * const *, char **));
 #endif
@@ -105,41 +103,51 @@ size_t	_EXFUN(mbstowcs,(wchar_t *__restrict, const char *__restrict, size_t));
 size_t	_EXFUN(_mbstowcs_r,(struct _reent *, wchar_t *__restrict, const char *__restrict, size_t, _mbstate_t *));
 size_t	_EXFUN(wcstombs,(char *__restrict, const wchar_t *__restrict, size_t));
 size_t	_EXFUN(_wcstombs_r,(struct _reent *, char *__restrict, const wchar_t *__restrict, size_t, _mbstate_t *));
-#ifndef __STRICT_ANSI__
 #ifndef _REENT_ONLY
+#if __BSD_VISIBLE || __POSIX_VISIBLE >= 200809
 char *	_EXFUN(mkdtemp,(char *));
+#endif
+#if __GNU_VISIBLE
 int	_EXFUN(mkostemp,(char *, int));
 int	_EXFUN(mkostemps,(char *, int, int));
+#endif
+#if __MISC_VISIBLE || __POSIX_VISIBLE >= 200112 || __XSI_VISIBLE >= 4
 int	_EXFUN(mkstemp,(char *));
+#endif
+#if __MISC_VISIBLE
 int	_EXFUN(mkstemps,(char *, int));
+#endif
+#if __BSD_VISIBLE || (__XSI_VISIBLE >= 4 && __POSIX_VISIBLE < 200112)
 char *	_EXFUN(mktemp,(char *) _ATTRIBUTE ((__deprecated__("the use of `mktemp' is dangerous; use `mkstemp' instead"))));
 #endif
+#endif /* !_REENT_ONLY */
 char *	_EXFUN(_mkdtemp_r, (struct _reent *, char *));
 int	_EXFUN(_mkostemp_r, (struct _reent *, char *, int));
 int	_EXFUN(_mkostemps_r, (struct _reent *, char *, int, int));
 int	_EXFUN(_mkstemp_r, (struct _reent *, char *));
 int	_EXFUN(_mkstemps_r, (struct _reent *, char *, int));
 char *	_EXFUN(_mktemp_r, (struct _reent *, char *) _ATTRIBUTE ((__deprecated__("the use of `mktemp' is dangerous; use `mkstemp' instead"))));
-#endif
 _VOID	_EXFUN(qsort,(_PTR __base, size_t __nmemb, size_t __size, __compar_fn_t _compar));
 int	_EXFUN(rand,(_VOID));
 _PTR	_EXFUN_NOTHROW(realloc,(_PTR __r, size_t __size));
-#ifndef __STRICT_ANSI__
+#if __BSD_VISIBLE
 _PTR	_EXFUN(reallocf,(_PTR __r, size_t __size));
+#endif
+#if __BSD_VISIBLE || __XSI_VISIBLE >= 4
 char *	_EXFUN(realpath, (const char *__restrict path, char *__restrict resolved_path));
+#endif
+#if __BSD_VISIBLE
 int	_EXFUN(rpmatch, (const char *response));
 #endif
 _VOID	_EXFUN(srand,(unsigned __seed));
 double	_EXFUN(strtod,(const char *__restrict __n, char **__restrict __end_PTR));
 double	_EXFUN(_strtod_r,(struct _reent *,const char *__restrict __n, char **__restrict __end_PTR));
-#if !defined(__STRICT_ANSI__) || \
-  (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) || \
-  (defined(__cplusplus) && __cplusplus >= 201103L)
+#if __ISO_C_VISIBLE >= 1999
 float	_EXFUN(strtof,(const char *__restrict __n, char **__restrict __end_PTR));
 #endif
-#ifndef __STRICT_ANSI__
+#if __MISC_VISIBLE
 /* the following strtodf interface is deprecated...use strtof instead */
-# ifndef strtodf 
+# ifndef strtodf
 #  define strtodf strtof
 # endif
 #endif
@@ -150,24 +158,28 @@ unsigned long _EXFUN(_strtoul_r,(struct _reent *,const char *__restrict __n, cha
 
 int	_EXFUN(system,(const char *__string));
 
-#ifndef __STRICT_ANSI__
+#if __SVID_VISIBLE || __XSI_VISIBLE >= 4
 long    _EXFUN(a64l,(const char *__input));
 char *  _EXFUN(l64a,(long __input));
 char *  _EXFUN(_l64a_r,(struct _reent *,long __input));
+#endif
+#if __MISC_VISIBLE
 int	_EXFUN(on_exit,(_VOID (*__func)(int, _PTR),_PTR __arg));
-#endif /* ! __STRICT_ANSI__ */
-#if !defined(__STRICT_ANSI__) || \
-  (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) || \
-  (defined(__cplusplus) && __cplusplus >= 201103L)
+#endif
+#if __ISO_C_VISIBLE >= 1999
 _VOID	_EXFUN(_Exit,(int __status) _ATTRIBUTE ((__noreturn__)));
 #endif
-#ifndef __STRICT_ANSI__
+#if __SVID_VISIBLE || __XSI_VISIBLE
 int	_EXFUN(putenv,(char *__string));
+#endif
 int	_EXFUN(_putenv_r,(struct _reent *, char *__string));
 _PTR	_EXFUN(_reallocf_r,(struct _reent *, _PTR, size_t));
+#if __BSD_VISIBLE || __POSIX_VISIBLE >= 200112
 int	_EXFUN(setenv,(const char *__string, const char *__value, int __overwrite));
+#endif
 int	_EXFUN(_setenv_r,(struct _reent *, const char *__string, const char *__value, int __overwrite));
 
+#if __XSI_VISIBLE >= 4 && __POSIX_VISIBLE < 200112
 char *	_EXFUN(gcvt,(double,int,char *));
 char *	_EXFUN(gcvtf,(float,int,char *));
 char *	_EXFUN(fcvt,(double,int,int *,int *));
@@ -176,15 +188,18 @@ char *	_EXFUN(ecvt,(double,int,int *,int *));
 char *	_EXFUN(ecvtbuf,(double, int, int*, int*, char *));
 char *	_EXFUN(fcvtbuf,(double, int, int*, int*, char *));
 char *	_EXFUN(ecvtf,(float,int,int *,int *));
-char *	_EXFUN(dtoa,(double, int, int, int *, int*, char**));
 #endif
 char *	_EXFUN(__itoa,(int, char *, int));
 char *	_EXFUN(__utoa,(unsigned, char *, int));
-#ifndef __STRICT_ANSI__
+#if __MISC_VISIBLE
 char *	_EXFUN(itoa,(int, char *, int));
 char *	_EXFUN(utoa,(unsigned, char *, int));
+#endif
+#if __POSIX_VISIBLE
 int	_EXFUN(rand_r,(unsigned *__seed));
+#endif
 
+#if __SVID_VISIBLE || __XSI_VISIBLE
 double _EXFUN(drand48,(_VOID));
 double _EXFUN(_drand48_r,(struct _reent *));
 double _EXFUN(erand48,(unsigned short [3]));
@@ -205,44 +220,37 @@ unsigned short *
        _EXFUN(_seed48_r,(struct _reent *, unsigned short [3]));
 _VOID  _EXFUN(srand48,(long));
 _VOID  _EXFUN(_srand48_r,(struct _reent *, long));
-#endif /* ! __STRICT_ANSI__ */
-#if !defined(__STRICT_ANSI__) || \
-  (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) || \
-  (defined(__cplusplus) && __cplusplus >= 201103L)
+#endif /* __SVID_VISIBLE || __XSI_VISIBLE */
+#if __ISO_C_VISIBLE >= 1999
 long long _EXFUN(atoll,(const char *__nptr));
 #endif
-#ifndef __STRICT_ANSI__
 long long _EXFUN(_atoll_r,(struct _reent *, const char *__nptr));
-#endif /* ! __STRICT_ANSI__ */
-#if !defined(__STRICT_ANSI__) || \
-  (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) || \
-  (defined(__cplusplus) && __cplusplus >= 201103L)
+#if __ISO_C_VISIBLE >= 1999
 long long _EXFUN(llabs,(long long));
 lldiv_t	_EXFUN(lldiv,(long long __numer, long long __denom));
 long long _EXFUN(strtoll,(const char *__restrict __n, char **__restrict __end_PTR, int __base));
 #endif
-#ifndef __STRICT_ANSI__
 long long _EXFUN(_strtoll_r,(struct _reent *, const char *__restrict __n, char **__restrict __end_PTR, int __base));
-#endif /* ! __STRICT_ANSI__ */
-#if !defined(__STRICT_ANSI__) || \
-  (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) || \
-  (defined(__cplusplus) && __cplusplus >= 201103L)
+#if __ISO_C_VISIBLE >= 1999
 unsigned long long _EXFUN(strtoull,(const char *__restrict __n, char **__restrict __end_PTR, int __base));
 #endif
-#ifndef __STRICT_ANSI__
 unsigned long long _EXFUN(_strtoull_r,(struct _reent *, const char *__restrict __n, char **__restrict __end_PTR, int __base));
 
 #ifndef __CYGWIN__
+#if __MISC_VISIBLE
 _VOID	_EXFUN(cfree,(_PTR));
+#endif
+#if __BSD_VISIBLE || __POSIX_VISIBLE >= 200112
 int	_EXFUN(unsetenv,(const char *__string));
-int	_EXFUN(_unsetenv_r,(struct _reent *, const char *__string));
 #endif
+int	_EXFUN(_unsetenv_r,(struct _reent *, const char *__string));
+#endif /* !__CYGWIN__ */
 
 #ifdef __rtems__
+#if __POSIX_VISIBLE >= 200112
 int _EXFUN(posix_memalign,(void **, size_t, size_t));
 #endif
-
-#endif /* ! __STRICT_ANSI__ */
+#endif
 
 char *	_EXFUN(_dtoa_r,(struct _reent *, double, int, int, int *, int*, char**));
 #ifndef __CYGWIN__
@@ -260,7 +268,9 @@ _VOID	_EXFUN(__eprintf,(const char *, const char *, unsigned int, const char *))
    _BSD_SOURCE, you get the BSD version; otherwise you get the GNU
    version.  We want that #undef qsort_r will still let you
    invoke the underlying function, but that requires gcc support. */
-#ifdef _BSD_SOURCE
+#if __GNU_VISIBLE
+_VOID	_EXFUN(qsort_r,(_PTR __base, size_t __nmemb, size_t __size, int (*_compar)(const _PTR, const _PTR, _PTR), _PTR __thunk));
+#elif __BSD_VISIBLE
 # ifdef __GNUC__
 _VOID	_EXFUN(qsort_r,(_PTR __base, size_t __nmemb, size_t __size, _PTR __thunk, int (*_compar)(_PTR, const _PTR, const _PTR)))
              __asm__ (__ASMNAME ("__bsd_qsort_r"));
@@ -268,16 +278,12 @@ _VOID	_EXFUN(qsort_r,(_PTR __base, size_t __nmemb, size_t __size, _PTR __thunk,
 _VOID	_EXFUN(__bsd_qsort_r,(_PTR __base, size_t __nmemb, size_t __size, _PTR __thunk, int (*_compar)(_PTR, const _PTR, const _PTR)));
 #  define qsort_r __bsd_qsort_r
 # endif
-#elif __GNU_VISIBLE
-_VOID	_EXFUN(qsort_r,(_PTR __base, size_t __nmemb, size_t __size, int (*_compar)(const _PTR, const _PTR, _PTR), _PTR __thunk));
 #endif
 
 /* On platforms where long double equals double.  */
 #ifdef _HAVE_LONG_DOUBLE
 extern long double _strtold_r (struct _reent *, const char *__restrict, char **__restrict);
-#if !defined(__STRICT_ANSI__) || \
-  (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) || \
-  (defined(__cplusplus) && __cplusplus >= 201103L)
+#if __ISO_C_VISIBLE >= 1999
 extern long double strtold (const char *__restrict, char **__restrict);
 #endif
 #endif /* _HAVE_LONG_DOUBLE */
@@ -285,7 +291,7 @@ extern long double strtold (const char *__restrict, char **__restrict);
 /*
  * If we're in a mode greater than C99, expose C11 functions.
  */
-#if __ISO_C_VISIBLE >= 2011 || __cplusplus >= 201103L
+#if __ISO_C_VISIBLE >= 2011
 void *	aligned_alloc(size_t, size_t) __malloc_like __alloc_align(1)
 	    __alloc_size(2);
 int	at_quick_exit(void (*)(void));
diff --git a/newlib/libc/search/qsort_r.c b/newlib/libc/search/qsort_r.c
index 0567be71e..9073061f0 100644
--- a/newlib/libc/search/qsort_r.c
+++ b/newlib/libc/search/qsort_r.c
@@ -52,5 +52,6 @@ PORTABILITY
 <<qsort_r>>, in various forms, appears in both BSD and glibc.
 */
 
+#define _GNU_SOURCE
 #define I_AM_GNU_QSORT_R
 #include "qsort.c"
diff --git a/newlib/libc/stdlib/efgcvt.c b/newlib/libc/stdlib/efgcvt.c
index 5d6e1aea3..b7d9812f6 100644
--- a/newlib/libc/stdlib/efgcvt.c
+++ b/newlib/libc/stdlib/efgcvt.c
@@ -131,6 +131,8 @@ Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,
 <<lseek>>, <<read>>, <<sbrk>>, <<write>>.
 */
 
+#define _XOPEN_SOURCE
+#define _XOPEN_SOURCE_EXTENDED
 #include <_ansi.h>
 #include <reent.h>
 #include <stdio.h>