strnlen, strict ansi, newlib vs glibc

Joel Sherrill
Fri Aug 15 16:06:00 GMT 2014

There were a couple of typos in the previous patch.  New one attached.

I am done for the week.

On 8/15/2014 9:23 AM, Joel Sherrill wrote:
> Attached is a new version of the patch. Comments interspersed.
> On 8/15/2014 6:52 AM, Corinna Vinschen wrote:
>> On Aug 14 17:53, Joel Sherrill wrote:
>>> This type of change is always tricky. FreeBSD's string.h only had
>>> __STRICT_ANSI__.  I read the glibc version and attempted to
>>> translate their feature flags into the BSD style ones we have
>>> from <sys/cdefs.h>.
>>> There are a few methods I have no idea how to guard:
>>> + The block of Windows strcmpi and friends at the bottom
>>> of the file.
>> Nuke them.  We don't have any Windows target, and Cygwin doesn't export
>> those.  They are likely a remnant from the time the Cygwin devs were
>> trying to make Cygwin a MSVCRT replacement (pre 1999).
> Done. :)
>>> + strlwr() and strupr(). No idea where those originated.
>> These ill-advised functions, which apparently predate any multibyte
>> concernes are actually in newlib.  They are ASCII only, non-standard,
>> and inherently broken by design.  So the question is, do we really want
>> to export them?  If so, maybe we should guard them with something like
>>   #ifdef __USE_NONSTD
> That does not appear anywhere in the source. I hate to add a new guard.
> They are wrapped in !defined(__STRICT_ANSI__).
> I am at a loss to do more.
>>> + _strerror_r() is another unknown origination.
>> This is the REENT version of strerror_r, as you already commented in
>> your patch.  In theory, these functions are outside of any standard,
>> just by having the underscore prepended.  I don't think they need
>> any standards guard.
> OK. I dropped my comment in the file about not knowing what to do.
>>> Attached is try1. I expect there to be a few rounds of this.
>>> I did build a complete sparc-rtems toolset and all RTEMS tests.
>>> Please check what I did and offer corrections and improvements.
>>> I tried to not rearrange the file. There is likely opportunity to
>>> group methods with similar guards.
>> Other than the above, looks good except:
>>> +#if (_XSI_VISIBLE - 0) >= 500
>> shouldn't be necessary.  If sys/cdefs.h is included, _XSI_VISIBLE
>> exists.
>>    #if _XSI_VISIBLE >= 500
>> should be sufficient.
> I fixed that pattern everywhere it occurred.
>> Thanks,
>> Corinna

Joel Sherrill, Ph.D.             Director of Research & Development        On-Line Applications Research
Ask me about RTEMS: a free RTOS  Huntsville AL 35805
Support Available                (256) 722-9985

-------------- next part --------------
Index: newlib/libc/include/string.h
RCS file: /cvs/src/src/newlib/libc/include/string.h,v
retrieving revision 1.35
diff -u -r1.35 string.h
--- newlib/libc/include/string.h	23 Jul 2013 07:05:30 -0000	1.35
+++ newlib/libc/include/string.h	15 Aug 2014 16:03:01 -0000
@@ -38,75 +38,108 @@
 char 	*_EXFUN(strrchr,(const char *, int));
 size_t	 _EXFUN(strspn,(const char *, const char *));
 char 	*_EXFUN(strstr,(const char *, const char *));
 #ifndef _REENT_ONLY
 char 	*_EXFUN(strtok,(char *__restrict, const char *__restrict));
 size_t	 _EXFUN(strxfrm,(char *__restrict, const char *__restrict, size_t));
-#ifndef __STRICT_ANSI__
 char 	*_EXFUN(strtok_r,(char *__restrict, const char *__restrict, char **__restrict));
 int	 _EXFUN(bcmp,(const void *, const void *, size_t));
 void	 _EXFUN(bcopy,(const void *, void *, size_t));
 void	 _EXFUN(bzero,(void *, size_t));
 int	 _EXFUN(ffs,(int));
 char 	*_EXFUN(index,(const char *, int));
 _PTR	 _EXFUN(memccpy,(_PTR __restrict, const _PTR __restrict, int, size_t));
 _PTR	 _EXFUN(mempcpy,(_PTR, const _PTR, size_t));
 _PTR	 _EXFUN(memmem, (const _PTR, size_t, const _PTR, size_t));
 _PTR 	 _EXFUN(memrchr,(const _PTR, int, size_t));
 _PTR 	 _EXFUN(rawmemchr,(const _PTR, int));
 char 	*_EXFUN(rindex,(const char *, int));
 char 	*_EXFUN(stpcpy,(char *__restrict, const char *__restrict));
 char 	*_EXFUN(stpncpy,(char *__restrict, const char *__restrict, size_t));
 int	 _EXFUN(strcasecmp,(const char *, const char *));
 char	*_EXFUN(strcasestr,(const char *, const char *));
 char 	*_EXFUN(strchrnul,(const char *, int));
-#if !defined(__STRICT_ANSI__) || (_XOPEN_SOURCE - 0) >= 500
+#if __XSI_VISIBLE >= 500
 char 	*_EXFUN(strdup,(const char *));
 #ifndef __STRICT_ANSI__
 char 	*_EXFUN(_strdup_r,(struct _reent *, const char *));
-#if !defined(__STRICT_ANSI__) || (_XOPEN_SOURCE - 0) >= 700
+#if __XSI_VISIBLE >= 700
 char 	*_EXFUN(strndup,(const char *, size_t));
 #ifndef __STRICT_ANSI__
 char 	*_EXFUN(_strndup_r,(struct _reent *, const char *, size_t));
 /* There are two common strerror_r variants.  If you request
    _GNU_SOURCE, you get the GNU version; otherwise you get the POSIX
    version.  POSIX requires that #undef strerror_r will still let you
    invoke the underlying function, but that requires gcc support.  */
-#ifdef _GNU_SOURCE
-char    *_EXFUN(strerror_r,(int, char *, size_t));
+char	*_EXFUN(strerror_r,(int, char *, size_t));
 # ifdef __GNUC__
-int      _EXFUN(strerror_r,(int, char *, size_t)) __asm__ (__ASMNAME ("__xpg_strerror_r"));
+int	_EXFUN(strerror_r,(int, char *, size_t))
+             __asm__ (__ASMNAME ("__xpg_strerror_r"));
 # else
-int      _EXFUN(__xpg_strerror_r,(int, char *, size_t));
+int	_EXFUN(__xpg_strerror_r,(int, char *, size_t));
 #  define strerror_r __xpg_strerror_r
 # endif
-size_t	 _EXFUN(strlcat,(char *, const char *, size_t));
-size_t	 _EXFUN(strlcpy,(char *, const char *, size_t));
-int	 _EXFUN(strncasecmp,(const char *, const char *, size_t));
+/* Reentrant version of strerror.  */
+char *	_EXFUN(_strerror_r, (struct _reent *, int, int, int *));
+size_t	_EXFUN(strlcat,(char *, const char *, size_t));
+size_t	_EXFUN(strlcpy,(char *, const char *, size_t));
+int	_EXFUN(strncasecmp,(const char *, const char *, size_t));
+#if !defined(__STRICT_ANSI__) || __XSI_VISIBLE >= 500
 size_t	 _EXFUN(strnlen,(const char *, size_t));
 char 	*_EXFUN(strsep,(char **, const char *));
+ * The origin of these is unknown to me so I am conditionalizing them
+ * on __STRICT_ANSI__. Finetuning this is definitely needed. --joel
+ */
+#if !defined(__STRICT_ANSI__)
 char	*_EXFUN(strlwr,(char *));
 char	*_EXFUN(strupr,(char *));
 #ifndef DEFS_H	/* Kludge to work around problem compiling in gdb */
-char  *_EXFUN(strsignal, (int __signo));
+char	*_EXFUN(strsignal, (int __signo));
 #ifdef __CYGWIN__
-int     _EXFUN(strtosigno, (const char *__name));
+int	_EXFUN(strtosigno, (const char *__name));
-/* Recursive version of strerror.  */
-char *	_EXFUN(_strerror_r, (struct _reent *, int, int, int *));
 #if defined _GNU_SOURCE && defined __GNUC__
 #define strdupa(__s) \
 	(__extension__ ({const char *__in = (__s); \
@@ -121,22 +154,6 @@
 			 (char *) memcpy (__out, __in, __len-1);}))
 #endif /* _GNU_SOURCE && __GNUC__ */
-/* These function names are used on Windows and perhaps other systems.  */
-#ifndef strcmpi
-#define strcmpi strcasecmp
-#ifndef stricmp
-#define stricmp strcasecmp
-#ifndef strncmpi
-#define strncmpi strncasecmp
-#ifndef strnicmp
-#define strnicmp strncasecmp
-#endif /* ! __STRICT_ANSI__ */
 #include <sys/string.h>

More information about the Newlib mailing list