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| PHP Version 5 |
| Copyright (c) 1997-2012 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: |
| |
| 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 |
| so we can mail you a copy immediately. |
| Author: Stig Sæther Bakken <> |
| Marcus Boerger <> |
/* $Id$ */
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.
#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;
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 ap_php_vasprintf(char **buf, const char *format, va_list ap);
PHPAPI int ap_php_asprintf(char **buf, const char *format, ...);
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);
#ifdef slprintf
#undef slprintf
#define slprintf ap_php_slprintf
#ifdef vslprintf
#undef vslprintf
#define vslprintf ap_php_vslprintf
#ifdef snprintf
#undef snprintf
#define snprintf ap_php_snprintf
#ifdef vsnprintf
#undef vsnprintf
#define vsnprintf ap_php_vsnprintf
#define vasprintf ap_php_vasprintf
#define asprintf ap_php_asprintf
#ifdef sprintf
#undef sprintf
#define sprintf php_sprintf
typedef enum {
LM_STD = 0,
} length_modifier_e;
#ifdef PHP_WIN32
# define WIDE_INT __int64
# define WIDE_INT long long int
# define WIDE_INT long long
# define WIDE_INT long
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) */
#endif /* SNPRINTF_H */
* Local variables:
* tab-width: 4
* c-basic-offset: 4
* End:
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