hush/libbb/printf.c
2003-04-16 23:02:35 +00:00

178 lines
5.7 KiB
C

/* vi: set sw=4 ts=4: */
/*
* *printf implementations for busybox
*
* Copyright (C) 2003 Manuel Novoa III <mjn3@codepoet.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
/* Mar 12, 2003 Manuel Novoa III
*
* While fwrite(), fputc(), fputs(), etc. all set the stream error flag
* on failure, the *printf functions are unique in that they can fail
* for reasons not related to the actual output itself. Among the possible
* reasons for failure which don't set the streams error indicator,
* SUSv3 lists EILSEQ, EINVAL, and ENOMEM.
*
* In some cases, it would be desireable to have a group of *printf()
* functions available that _always_ set the stream error indicator on
* failure. That would allow us to defer error checking until applet
* exit. Unfortunately, there is no standard way of setting a streams
* error indicator... even though we can clear it with clearerr().
*
* Therefore, we have to resort to implementation dependent code. Feel
* free to send patches for stdio implementations where the following
* fails.
*
* NOTE: None of this is threadsafe. As busybox is a nonthreaded app,
* that isn't currently an issue.
*/
#include <stdio.h>
#include <stdarg.h>
#include "libbb.h"
#if defined(__UCLIBC__)
# if defined(__FLAG_ERROR)
/* Using my newer stdio implementation. Unlocked macros are:
* #define __CLEARERR(stream) \
((stream)->modeflags &= ~(__FLAG_EOF|__FLAG_ERROR), (void)0)
* #define __FEOF(stream) ((stream)->modeflags & __FLAG_EOF)
* #define __FERROR(stream) ((stream)->modeflags & __FLAG_ERROR)
*/
#define SET_FERROR_UNLOCKED(S) ((S)->modeflags |= __FLAG_ERROR)
#elif defined(__MODE_ERR)
/* Using either the original stdio implementation (from dev86) or
* my original stdio rewrite. Macros were:
* #define ferror(fp) (((fp)->mode&__MODE_ERR) != 0)
* #define feof(fp) (((fp)->mode&__MODE_EOF) != 0)
* #define clearerr(fp) ((fp)->mode &= ~(__MODE_EOF|__MODE_ERR),0)
*/
#define SET_FERROR_UNLOCKED(S) ((S)->mode |= __MODE_ERR)
#else
#error unknown uClibc stdio implemenation!
#endif
#elif defined(__GLIBC__)
# if defined(_STDIO_USES_IOSTREAM)
/* Apparently using the newer libio implementation, with associated defines:
* #define _IO_feof_unlocked(__fp) (((__fp)->_flags & _IO_EOF_SEEN) != 0)
* #define _IO_ferror_unlocked(__fp) (((__fp)->_flags & _IO_ERR_SEEN) != 0)
*/
#define SET_FERROR_UNLOCKED(S) ((S)->_flags |= _IO_ERR_SEEN)
# else
/* Assume the older version of glibc which used a bitfield entry
* as a stream error flag. The associated defines were:
* #define __clearerr(stream) ((stream)->__error = (stream)->__eof = 0)
* #define feof_unlocked(stream) ((stream)->__eof != 0)
* #define ferror_unlocked(stream) ((stream)->__error != 0)
*/
#define SET_FERROR_UNLOCKED(S) ((S)->__error = 1)
# endif
#elif defined(__NEWLIB_H__)
/* I honestly don't know if there are different versions of stdio in
* newlibs history. Anyway, here's what's current.
* #define __sfeof(p) (((p)->_flags & __SEOF) != 0)
* #define __sferror(p) (((p)->_flags & __SERR) != 0)
* #define __sclearerr(p) ((void)((p)->_flags &= ~(__SERR|__SEOF)))
*/
#define SET_FERROR_UNLOCKED(S) ((S)->_flags |= __SERR)
#elif defined(__dietlibc__)
/*
* WARNING!!! dietlibc is quite buggy. WARNING!!!
*
* Some example bugs as of March 12, 2003...
* 1) fputc() doesn't set the error indicator on failure.
* 2) freopen() doesn't maintain the same stream object, contary to
* standards. This makes it useless in its primary role of
* reassociating stdin/stdout/stderr.
* 3) printf() often fails to correctly format output when conversions
* involve padding. It is also practically useless for floating
* point output.
*
* But, if you're determined to use it anyway, (as of the current version)
* you can extract the information you need from dietstdio.h. See the
* other library implementations for examples.
*/
#error dietlibc is currently not supported. Please see the commented source.
#else /* some other lib */
/* Please see the comments for the above supported libaries for examples
* of what is required to support your stdio implementation.
*/
#error Your stdio library is currently not supported. Please see the commented source.
#endif
#ifdef L_bb_vfprintf
extern int bb_vfprintf(FILE * __restrict stream,
const char * __restrict format,
va_list arg)
{
int rv;
if ((rv = vfprintf(stream, format, arg)) < 0) {
SET_FERROR_UNLOCKED(stream);
}
return rv;
}
#endif
#ifdef L_bb_vprintf
extern int bb_vprintf(const char * __restrict format, va_list arg)
{
return bb_vfprintf(stdout, format, arg);
}
#endif
#ifdef L_bb_fprintf
extern int bb_fprintf(FILE * __restrict stream,
const char * __restrict format, ...)
{
va_list arg;
int rv;
va_start(arg, format);
rv = bb_vfprintf(stream, format, arg);
va_end(arg);
return rv;
}
#endif
#ifdef L_bb_printf
extern int bb_printf(const char * __restrict format, ...)
{
va_list arg;
int rv;
va_start(arg, format);
rv = bb_vfprintf(stdout, format, arg);
va_end(arg);
return rv;
}
#endif