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e14fbc84ac
This used to be necessary in the past because the NUM_BUF_SIZE was set to 512, which is shorter than DOUBLE_MAX_LENGTH. Now the value is either DOUBLE_MAX_LENGTH or larger (2048).
137 lines
5.6 KiB
C
137 lines
5.6 KiB
C
/*
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+----------------------------------------------------------------------+
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| Copyright (c) The PHP Group |
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+----------------------------------------------------------------------+
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| This source file is subject to version 3.01 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 through the world-wide-web at the following url: |
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| https://www.php.net/license/3_01.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@php.net> |
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| Marcus Boerger <helly@php.net> |
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+----------------------------------------------------------------------+
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*/
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/*
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Comparing: sprintf, snprintf, slprintf, 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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always terminates 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 being 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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The function also returns the number of chars not including the
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terminating \0 that were needed to fully comply to the print request.
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slprintf same as snprintf with the difference that it actually returns the
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length printed not including the terminating \0.
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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 leaks if you miss freeing the
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buffer allocated by the function. Therefore 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 always 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 always 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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#include <stdbool.h>
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BEGIN_EXTERN_C()
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PHPAPI int ap_php_slprintf(char *buf, size_t len, const char *format,...) ZEND_ATTRIBUTE_FORMAT(printf, 3, 4);
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PHPAPI int ap_php_vslprintf(char *buf, size_t len, const char *format, va_list ap);
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PHPAPI int ap_php_snprintf(char *, size_t, const char *, ...) ZEND_ATTRIBUTE_FORMAT(printf, 3, 4);
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PHPAPI int ap_php_vsnprintf(char *, size_t, const char *, va_list ap);
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PHPAPI int ap_php_vasprintf(char **buf, const char *format, va_list ap);
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PHPAPI int ap_php_asprintf(char **buf, const char *format, ...) ZEND_ATTRIBUTE_FORMAT(printf, 2, 3);
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PHPAPI char * php_0cvt(double value, int ndigit, char dec_point, char exponent, char *buf);
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PHPAPI char * php_conv_fp(char format, double num,
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bool add_dp, int precision, char dec_point, bool * is_negative, char *buf, size_t *len);
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END_EXTERN_C()
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#define php_gcvt zend_gcvt
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#ifdef slprintf
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#undef slprintf
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#endif
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#define slprintf ap_php_slprintf
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#ifdef vslprintf
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#undef vslprintf
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#endif
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#define vslprintf ap_php_vslprintf
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#ifdef snprintf
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#undef snprintf
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#endif
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#define snprintf ap_php_snprintf
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#ifdef vsnprintf
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#undef vsnprintf
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#endif
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#define vsnprintf ap_php_vsnprintf
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#ifndef HAVE_VASPRINTF
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#define vasprintf ap_php_vasprintf
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#endif
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#ifndef HAVE_ASPRINTF
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#define asprintf ap_php_asprintf
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#endif
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typedef enum {
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LM_STD = 0,
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#if SIZEOF_INTMAX_T
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LM_INTMAX_T,
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#endif
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#if SIZEOF_PTRDIFF_T
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LM_PTRDIFF_T,
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#endif
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#if SIZEOF_LONG_LONG
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LM_LONG_LONG,
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#endif
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LM_SIZE_T,
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LM_LONG,
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LM_LONG_DOUBLE,
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} length_modifier_e;
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PHPAPI char * ap_php_conv_10(int64_t num, bool is_unsigned,
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bool * is_negative, char *buf_end, size_t *len);
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PHPAPI char * ap_php_conv_p2(uint64_t num, int nbits,
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char format, char *buf_end, size_t *len);
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#endif /* SNPRINTF_H */
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