105436638acc7c010349a69c3395f1a57c642dc62Ying Wang/* vsprintf with automatic memory allocation. 205436638acc7c010349a69c3395f1a57c642dc62Ying Wang Copyright (C) 2002-2004, 2007-2012 Free Software Foundation, Inc. 305436638acc7c010349a69c3395f1a57c642dc62Ying Wang 405436638acc7c010349a69c3395f1a57c642dc62Ying Wang This program is free software; you can redistribute it and/or modify 505436638acc7c010349a69c3395f1a57c642dc62Ying Wang it under the terms of the GNU General Public License as published by 605436638acc7c010349a69c3395f1a57c642dc62Ying Wang the Free Software Foundation; either version 3, or (at your option) 705436638acc7c010349a69c3395f1a57c642dc62Ying Wang any later version. 805436638acc7c010349a69c3395f1a57c642dc62Ying Wang 905436638acc7c010349a69c3395f1a57c642dc62Ying Wang This program is distributed in the hope that it will be useful, 1005436638acc7c010349a69c3395f1a57c642dc62Ying Wang but WITHOUT ANY WARRANTY; without even the implied warranty of 1105436638acc7c010349a69c3395f1a57c642dc62Ying Wang MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 1205436638acc7c010349a69c3395f1a57c642dc62Ying Wang GNU General Public License for more details. 1305436638acc7c010349a69c3395f1a57c642dc62Ying Wang 1405436638acc7c010349a69c3395f1a57c642dc62Ying Wang You should have received a copy of the GNU General Public License along 1505436638acc7c010349a69c3395f1a57c642dc62Ying Wang with this program; if not, see <http://www.gnu.org/licenses/>. */ 1605436638acc7c010349a69c3395f1a57c642dc62Ying Wang 1705436638acc7c010349a69c3395f1a57c642dc62Ying Wang#ifndef _VASNPRINTF_H 1805436638acc7c010349a69c3395f1a57c642dc62Ying Wang#define _VASNPRINTF_H 1905436638acc7c010349a69c3395f1a57c642dc62Ying Wang 2005436638acc7c010349a69c3395f1a57c642dc62Ying Wang/* Get va_list. */ 2105436638acc7c010349a69c3395f1a57c642dc62Ying Wang#include <stdarg.h> 2205436638acc7c010349a69c3395f1a57c642dc62Ying Wang 2305436638acc7c010349a69c3395f1a57c642dc62Ying Wang/* Get size_t. */ 2405436638acc7c010349a69c3395f1a57c642dc62Ying Wang#include <stddef.h> 2505436638acc7c010349a69c3395f1a57c642dc62Ying Wang 2605436638acc7c010349a69c3395f1a57c642dc62Ying Wang/* The __attribute__ feature is available in gcc versions 2.5 and later. 2705436638acc7c010349a69c3395f1a57c642dc62Ying Wang The __-protected variants of the attributes 'format' and 'printf' are 2805436638acc7c010349a69c3395f1a57c642dc62Ying Wang accepted by gcc versions 2.6.4 (effectively 2.7) and later. 2905436638acc7c010349a69c3395f1a57c642dc62Ying Wang We enable _GL_ATTRIBUTE_FORMAT only if these are supported too, because 3005436638acc7c010349a69c3395f1a57c642dc62Ying Wang gnulib and libintl do '#define printf __printf__' when they override 3105436638acc7c010349a69c3395f1a57c642dc62Ying Wang the 'printf' function. */ 3205436638acc7c010349a69c3395f1a57c642dc62Ying Wang#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 7) 3305436638acc7c010349a69c3395f1a57c642dc62Ying Wang# define _GL_ATTRIBUTE_FORMAT(spec) __attribute__ ((__format__ spec)) 3405436638acc7c010349a69c3395f1a57c642dc62Ying Wang#else 3505436638acc7c010349a69c3395f1a57c642dc62Ying Wang# define _GL_ATTRIBUTE_FORMAT(spec) /* empty */ 3605436638acc7c010349a69c3395f1a57c642dc62Ying Wang#endif 3705436638acc7c010349a69c3395f1a57c642dc62Ying Wang 3805436638acc7c010349a69c3395f1a57c642dc62Ying Wang#ifdef __cplusplus 3905436638acc7c010349a69c3395f1a57c642dc62Ying Wangextern "C" { 4005436638acc7c010349a69c3395f1a57c642dc62Ying Wang#endif 4105436638acc7c010349a69c3395f1a57c642dc62Ying Wang 4205436638acc7c010349a69c3395f1a57c642dc62Ying Wang/* Write formatted output to a string dynamically allocated with malloc(). 4305436638acc7c010349a69c3395f1a57c642dc62Ying Wang You can pass a preallocated buffer for the result in RESULTBUF and its 4405436638acc7c010349a69c3395f1a57c642dc62Ying Wang size in *LENGTHP; otherwise you pass RESULTBUF = NULL. 4505436638acc7c010349a69c3395f1a57c642dc62Ying Wang If successful, return the address of the string (this may be = RESULTBUF 4605436638acc7c010349a69c3395f1a57c642dc62Ying Wang if no dynamic memory allocation was necessary) and set *LENGTHP to the 4705436638acc7c010349a69c3395f1a57c642dc62Ying Wang number of resulting bytes, excluding the trailing NUL. Upon error, set 4805436638acc7c010349a69c3395f1a57c642dc62Ying Wang errno and return NULL. 4905436638acc7c010349a69c3395f1a57c642dc62Ying Wang 5005436638acc7c010349a69c3395f1a57c642dc62Ying Wang When dynamic memory allocation occurs, the preallocated buffer is left 5105436638acc7c010349a69c3395f1a57c642dc62Ying Wang alone (with possibly modified contents). This makes it possible to use 5205436638acc7c010349a69c3395f1a57c642dc62Ying Wang a statically allocated or stack-allocated buffer, like this: 5305436638acc7c010349a69c3395f1a57c642dc62Ying Wang 5405436638acc7c010349a69c3395f1a57c642dc62Ying Wang char buf[100]; 5505436638acc7c010349a69c3395f1a57c642dc62Ying Wang size_t len = sizeof (buf); 5605436638acc7c010349a69c3395f1a57c642dc62Ying Wang char *output = vasnprintf (buf, &len, format, args); 5705436638acc7c010349a69c3395f1a57c642dc62Ying Wang if (output == NULL) 5805436638acc7c010349a69c3395f1a57c642dc62Ying Wang ... error handling ...; 5905436638acc7c010349a69c3395f1a57c642dc62Ying Wang else 6005436638acc7c010349a69c3395f1a57c642dc62Ying Wang { 6105436638acc7c010349a69c3395f1a57c642dc62Ying Wang ... use the output string ...; 6205436638acc7c010349a69c3395f1a57c642dc62Ying Wang if (output != buf) 6305436638acc7c010349a69c3395f1a57c642dc62Ying Wang free (output); 6405436638acc7c010349a69c3395f1a57c642dc62Ying Wang } 6505436638acc7c010349a69c3395f1a57c642dc62Ying Wang */ 6605436638acc7c010349a69c3395f1a57c642dc62Ying Wang#if REPLACE_VASNPRINTF 6705436638acc7c010349a69c3395f1a57c642dc62Ying Wang# define asnprintf rpl_asnprintf 6805436638acc7c010349a69c3395f1a57c642dc62Ying Wang# define vasnprintf rpl_vasnprintf 6905436638acc7c010349a69c3395f1a57c642dc62Ying Wang#endif 7005436638acc7c010349a69c3395f1a57c642dc62Ying Wangextern char * asnprintf (char *resultbuf, size_t *lengthp, const char *format, ...) 7105436638acc7c010349a69c3395f1a57c642dc62Ying Wang _GL_ATTRIBUTE_FORMAT ((__printf__, 3, 4)); 7205436638acc7c010349a69c3395f1a57c642dc62Ying Wangextern char * vasnprintf (char *resultbuf, size_t *lengthp, const char *format, va_list args) 7305436638acc7c010349a69c3395f1a57c642dc62Ying Wang _GL_ATTRIBUTE_FORMAT ((__printf__, 3, 0)); 7405436638acc7c010349a69c3395f1a57c642dc62Ying Wang 7505436638acc7c010349a69c3395f1a57c642dc62Ying Wang#ifdef __cplusplus 7605436638acc7c010349a69c3395f1a57c642dc62Ying Wang} 7705436638acc7c010349a69c3395f1a57c642dc62Ying Wang#endif 7805436638acc7c010349a69c3395f1a57c642dc62Ying Wang 7905436638acc7c010349a69c3395f1a57c642dc62Ying Wang#endif /* _VASNPRINTF_H */ 80