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Editing: snprintf.h
/* +----------------------------------------------------------------------+ | PHP Version 5 | +----------------------------------------------------------------------+ | Copyright (c) 1997-2010 The PHP Group | +----------------------------------------------------------------------+ | This source file is subject to version 3.01 of the PHP license, | | that is bundled with this package in the file LICENSE, and is | | available through the world-wide-web at the following url: | | http://www.php.net/license/3_01.txt | | If you did not receive a copy of the PHP license and are unable to | | obtain it through the world-wide-web, please send a note to | | license@php.net so we can mail you a copy immediately. | +----------------------------------------------------------------------+ | Author: Stig Sæther Bakken <ssb@php.net> | | Marcus Boerger <helly@php.net> | +----------------------------------------------------------------------+ */ /* $Id: snprintf.h 293036 2010-01-03 09:23:27Z sebastian $ */ /* Comparing: sprintf, snprintf, slprintf, spprintf sprintf offers the ability to make a lot of failures since it does not know the size of the buffer it uses. Therefore usage of sprintf often results in possible entries for buffer overrun attacks. So please use this version only if you are sure the call is safe. sprintf allways terminstes the buffer it writes to. snprintf knows the buffers size and will not write behind it. But you will have to use either a static buffer or allocate a dynamic buffer before beeing able to call the function. In other words you must be sure that you really know the maximum size of the buffer required. A bad thing is having a big maximum while in most cases you would only need a small buffer. If the size of the resulting string is longer or equal to the buffer size than the buffer is not terminated. The function also returns the number of chars not including the terminating \0 that were needed to fully comply to the print request. slprintf same as snprintf with the difference that it actually returns the length printed not including the terminating \0. spprintf is the dynamical version of snprintf. It allocates the buffer in size as needed and allows a maximum setting as snprintf (turn this feature off by setting max_len to 0). spprintf is a little bit slower than snprintf and offers possible memory leakes if you miss freeing the buffer allocated by the function. Therfore this function should be used where either no maximum is known or the maximum is much bigger than normal size required. spprintf allways terminates the buffer. Example: #define MAX 1024 | #define MAX 1024 | #define MAX 1024 char buffer[MAX] | char buffer[MAX] | char *buffer; | | | | // No need to initialize buffer: | | // spprintf ignores value of buffer sprintf(buffer, "test"); | snprintf(buffer, MAX, "test"); | spprintf(&buffer, MAX, "text"); | | if (!buffer) | | return OUT_OF_MEMORY // sprintf allways terminates | // manual termination of | // spprintf allays terminates buffer // buffer | // buffer *IS* required | | buffer[MAX-1] = 0; | action_with_buffer(buffer); | action_with_buffer(buffer); | action_with_buffer(buffer); | | efree(buffer); */ #ifndef SNPRINTF_H #define SNPRINTF_H typedef int bool_int; typedef enum { NO = 0, YES = 1 } boolean_e; BEGIN_EXTERN_C() PHPAPI int ap_php_slprintf(char *buf, size_t len, const char *format,...); PHPAPI int ap_php_vslprintf(char *buf, size_t len, const char *format, va_list ap); PHPAPI int ap_php_snprintf(char *, size_t, const char *, ...); PHPAPI int ap_php_vsnprintf(char *, size_t, const char *, va_list ap); PHPAPI int php_sprintf (char* s, const char* format, ...) PHP_ATTRIBUTE_FORMAT(printf, 2, 3); PHPAPI char * php_gcvt(double value, int ndigit, char dec_point, char exponent, char *buf); PHPAPI char * php_conv_fp(register char format, register double num, boolean_e add_dp, int precision, char dec_point, bool_int * is_negative, char *buf, int *len); END_EXTERN_C() #ifdef slprintf #undef slprintf #endif #define slprintf ap_php_slprintf #ifdef vslprintf #undef vslprintf #endif #define vslprintf ap_php_vslprintf #ifdef snprintf #undef snprintf #endif #define snprintf ap_php_snprintf #ifdef vsnprintf #undef vsnprintf #endif #define vsnprintf ap_php_vsnprintf #ifdef sprintf #undef sprintf #endif #define sprintf php_sprintf typedef enum { LM_STD = 0, #if SIZEOF_INTMAX_T LM_INTMAX_T, #endif #if SIZEOF_PTRDIFF_T LM_PTRDIFF_T, #endif #if SIZEOF_LONG_LONG LM_LONG_LONG, #endif LM_SIZE_T, LM_LONG, LM_LONG_DOUBLE } length_modifier_e; #ifdef PHP_WIN32 # define WIDE_INT __int64 #elif SIZEOF_LONG_LONG_INT # define WIDE_INT long long int #elif SIZEOF_LONG_LONG # define WIDE_INT long long #else # define WIDE_INT long #endif typedef WIDE_INT wide_int; typedef unsigned WIDE_INT u_wide_int; extern char * ap_php_conv_10(register wide_int num, register bool_int is_unsigned, register bool_int * is_negative, char *buf_end, register int *len); extern char * ap_php_conv_p2(register u_wide_int num, register int nbits, char format, char *buf_end, register int *len); /* The maximum precision that's allowed for float conversion. Does not include * decimal separator, exponent, sign, terminator. Currently does not affect * the modes e/f, only g/k/H, as those have a different limit enforced at * another level (see NDIG in php_conv_fp()). * Applies to the formatting functions of both spprintf.c and snprintf.c, which * use equally sized buffers of MAX_BUF_SIZE = 512 to hold the result of the * call to php_gcvt(). * This should be reasonably smaller than MAX_BUF_SIZE (I think MAX_BUF_SIZE - 9 * should be enough, but let's give some more space) */ #define FORMAT_CONV_MAX_PRECISION 500 #endif /* SNPRINTF_H */ /* * Local variables: * tab-width: 4 * c-basic-offset: 4 * End: */
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