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302bfefac7
#before complaining snprintf is often used wrong: #snprintf does not terminate the buffer but most people expect it #that could be a security isuue at somewhere
113 lines
5.1 KiB
C
113 lines
5.1 KiB
C
/*
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+----------------------------------------------------------------------+
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| PHP Version 4 |
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+----------------------------------------------------------------------+
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| Copyright (c) 1997-2002 The PHP Group |
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+----------------------------------------------------------------------+
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| This source file is subject to version 2.02 of the PHP license, |
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| that is bundled with this package in the file LICENSE, and is |
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| available at through the world-wide-web at |
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| http://www.php.net/license/2_02.txt. |
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| If you did not receive a copy of the PHP license and are unable to |
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| obtain it through the world-wide-web, please send a note to |
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| license@php.net so we can mail you a copy immediately. |
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+----------------------------------------------------------------------+
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| Author: Stig Sæther Bakken <ssb@fast.no> |
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+----------------------------------------------------------------------+
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*/
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/*
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Comparing: sprintf, snprintf, spprintf
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sprintf offers the ability to make a lot of failures since it does not know
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the size of the buffer it uses. Therefore usage of sprintf often
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results in possible entries for buffer overrun attacks. So please
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use this version only if you are sure the call is safe. sprintf
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allways terminstes the buffer it writes to.
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snprintf knows the buffers size and will not write behind it. But you will
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have to use either a static buffer or allocate a dynamic buffer
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before beeing able to call the function. In other words you must
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be sure that you really know the maximum size of the buffer required.
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A bad thing is having a big maximum while in most cases you would
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only need a small buffer. If the size of the resulting string is
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longer or equal to the buffer size than the buffer is not terminated.
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spprintf is the dynamical version of snprintf. It allocates the buffer in size
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as needed and allows a maximum setting as snprintf (turn this feature
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off by setting max_len to 0). spprintf is a little bit slower than
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snprintf and offers possible memory leakes if you miss freeing the
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buffer allocated by the function. Therfore this function should be
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used where either no maximum is known or the maximum is much bigger
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than normal size required. spprintf allways terminates the buffer.
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Example:
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#define MAX 1024 | #define MAX 1024 | #define MAX 1024
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char buffer[MAX] | char buffer[MAX] | char *buffer;
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| |
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| | // No need to initialize buffer:
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| | // spprintf ignores value of buffer
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sprintf(buffer, "test"); | snprintf(buffer, MAX, "test"); | spprintf(&buffer, MAX, "text");
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| | if (!buffer)
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| | return OUT_OF_MEMORY
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// sprintf allways terminates | // manual termination of | // spprintf allays terminates buffer
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// buffer | // buffer *IS* required |
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| buffer[MAX-1] = 0; |
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action_with_buffer(buffer); | action_with_buffer(buffer); | action_with_buffer(buffer);
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| | efree(buffer);
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*/
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#ifndef SNPRINTF_H
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#define SNPRINTF_H
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#if !defined(HAVE_SNPRINTF) || defined(BROKEN_SNPRINTF)
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extern int ap_php_snprintf(char *, size_t, const char *, ...);
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#define snprintf ap_php_snprintf
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#endif
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#if !defined(HAVE_VSNPRINTF) || defined(BROKEN_VSNPRINTF)
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extern int ap_php_vsnprintf(char *, size_t, const char *, va_list ap);
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#define vsnprintf ap_php_vsnprintf
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#endif
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#if PHP_BROKEN_SPRINTF
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int php_sprintf (char* s, const char* format, ...);
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#define sprintf php_sprintf
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#endif
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typedef enum {
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NO = 0, YES = 1
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} boolean_e;
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extern char * ap_php_cvt(double arg, int ndigits, int *decpt, int *sign, int eflag, char *buf);
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extern char * ap_php_ecvt(double arg, int ndigits, int *decpt, int *sign, char *buf);
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extern char * ap_php_fcvt(double arg, int ndigits, int *decpt, int *sign, char *buf);
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extern char * ap_php_gcvt(double number, int ndigit, char *buf, boolean_e altform);
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#define WIDE_INT long
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typedef WIDE_INT wide_int;
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typedef unsigned WIDE_INT u_wide_int;
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typedef int bool_int;
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extern char * ap_php_conv_10(register wide_int num, register bool_int is_unsigned,
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register bool_int * is_negative, char *buf_end, register int *len);
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extern char * ap_php_conv_fp(register char format, register double num,
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boolean_e add_dp, int precision, bool_int * is_negative, char *buf, int *len);
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extern char * ap_php_conv_p2(register u_wide_int num, register int nbits,
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char format, char *buf_end, register int *len);
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#endif /* SNPRINTF_H */
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/*
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* Local variables:
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* tab-width: 4
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* c-basic-offset: 4
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* End:
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*/
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