efl/legacy/eina/src/lib/eina_convert.c

587 lines
14 KiB
C

/* EINA - EFL data type library
* Copyright (C) 2008 Cedric BAIL, Vincent Torri
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library;
* if not, see <http://www.gnu.org/licenses/>.
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <math.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include "eina_config.h"
#include "eina_private.h"
#include "eina_log.h"
#include "eina_safety_checks.h"
#include "eina_convert.h"
/*============================================================================*
* Local *
*============================================================================*/
/**
* @cond LOCAL
*/
static const char look_up_table[] = {'0', '1', '2', '3', '4',
'5', '6', '7', '8', '9',
'a', 'b', 'c', 'd', 'e', 'f'};
static int _eina_convert_init_count = 0;
static int _eina_convert_log_dom = -1;
#define ERR(...) EINA_LOG_DOM_ERR(_eina_convert_log_dom, __VA_ARGS__)
#define DBG(...) EINA_LOG_DOM_DBG(_eina_convert_log_dom, __VA_ARGS__)
#define HEXA_TO_INT(Hexa) (Hexa >= 'a') ? Hexa - 'a' + 10 : Hexa - '0'
static inline void reverse(char s[], int length)
{
int i, j;
char c;
for (i = 0, j = length - 1; i < j; i++, j--)
{
c = s[i];
s[i] = s[j];
s[j] = c;
}
}
/**
* @endcond
*/
/*============================================================================*
* Global *
*============================================================================*/
/*============================================================================*
* API *
*============================================================================*/
/**
* @cond LOCAL
*/
EAPI Eina_Error EINA_ERROR_CONVERT_P_NOT_FOUND = 0;
EAPI Eina_Error EINA_ERROR_CONVERT_0X_NOT_FOUND = 0;
EAPI Eina_Error EINA_ERROR_CONVERT_OUTRUN_STRING_LENGTH = 0;
/**
* @endcond
*/
/**
* @addtogroup Eina_Convert_Group Convert
*
* These functions allow you to convert integer or real numbers to
* string or conversely.
*
* To use these function, you have to call eina_convert_init()
* first, and eina_convert_shutdown() when they are not used anymore.
*
* @section Eina_Convert_From_Integer_To_Sring Conversion from integer to string
*
* To convert an integer to a string in the decimal base,
* eina_convert_itoa() should be used. If the hexadecimal base is
* wanted, eina_convert_xtoa() should be used. They all need a bufffer
* sufficiently large to store all the cyphers.
*
* Here is an exemple of use:
*
* @code
* #include <stdlib.h>
* #include <stdio.h>
*
* #include <eina_convert.h>
*
* int main(void)
* {
* char *tmp[128];
*
* if (!eina_convert_init())
* {
* printf ("Error during the initialization of eina_convert module\n");
* return EXIT_FAILURE;
* }
*
* eina_convert_itoa(45, tmp);
* printf("value: %s\n", tmp);
* eina_convert_xtoa(0xA1, tmp);
* printf("value: %s\n", tmp);
*
* eina_convert_shutdown();
*
* return EXIT_SUCCESS;
* }
* @endcode
*
* Compile this code with the following commant:
*
* @code
* gcc -Wall -o test_eina_convert test_eina.c `pkg-config --cflags --libs eina`
* @endcode
*
* @note
* The alphabetical cyphers are in lower case.
*
* @section Eina_Convert_Double Conversion double / string
*
* To convert a double to a string, eina_convert_dtoa() should be
* used. Like with the integer functions, a buffer must be used. The
* resulting string ghas the following format (which is the result
* obtained with snprintf() and the @%a modifier):
*
* @code
* [-]0xh.hhhhhp[+-]e
* @endcode
*
* To convert a string to a double, eina_convert_atod() should be
* used. The format of the string must be as above. Then, the double
* has the following mantiss and exponent:
*
* @code
* mantiss : [-]hhhhhh
* exponent : 2^([+-]e - 4 * n)
* @endcode
*
* with n being number of cypers after the point in the string
* format. To obtain the double number from the mantiss and exponent,
* use ldexp().
*
* Here is an exemple of use:
*
* @code
* #include <stdlib.h>
* #include <stdio.h>
*
* #include <eina_convert.h>
*
* int main(void)
* {
* char *tmp[128];
* long long int m = 0;
* long int e = 0;
* doule r;
*
* if (!eina_convert_init())
* {
* printf ("Error during the initialization of eina_convert module\n");
* return EXIT_FAILURE;
* }
*
* eina_convert_dtoa(40.56, tmp);
* printf("value: %s\n", tmp);
* eina_convert_atod(tmp, 128, &m, &e);
* r = ldexp((double)m, e);
* printf("value: %s\n", tmp);
*
* eina_convert_shutdown();
*
* return EXIT_SUCCESS;
* }
* @endcode
*
* Compile this code with the same command as above.
*
* @{
*/
/**
* @brief Initialize the eina convert internal structure.
*
* @return 1 or greater on success, 0 on error.
*
* This function sets up the error module of Eina and registers the
* errors #EINA_ERROR_CONVERT_0X_NOT_FOUND,
* #EINA_ERROR_CONVERT_P_NOT_FOUND and
* #EINA_ERROR_CONVERT_OUTRUN_STRING_LENGTH. It is also called by
* eina_init(). It returns 0 on failure, otherwise it returns the
* number of times it has already been called.
*/
EAPI int
eina_convert_init(void)
{
_eina_convert_init_count++;
if (_eina_convert_init_count > 1) goto init_out;
eina_error_init();
EINA_ERROR_CONVERT_0X_NOT_FOUND = eina_error_msg_register("Error during string convertion to float, First '0x' was not found.");
EINA_ERROR_CONVERT_P_NOT_FOUND = eina_error_msg_register("Error during string convertion to float, First 'p' was not found.");
EINA_ERROR_CONVERT_OUTRUN_STRING_LENGTH = eina_error_msg_register("Error outrun string limit during convertion string convertion to float.");
if (!eina_log_init())
{
fprintf(stderr, "Could not initialize eina logging system.\n");
eina_error_shutdown();
return 0;
}
_eina_convert_log_dom = eina_log_domain_register("eina_convert", EINA_LOG_COLOR_DEFAULT);
if (_eina_convert_log_dom < 0)
{
EINA_LOG_ERR("Could not register log domain: eina_convert");
eina_log_shutdown();
eina_error_shutdown();
return 0;
}
if (!eina_safety_checks_init())
{
ERR("Could not initialize eina safety checks.");
eina_log_shutdown();
eina_error_shutdown();
return 0;
}
init_out:
return _eina_convert_init_count;
}
/**
* @brief Shut down the eina convert internal structures
*
* @return 0 when the convert module is completely shut down, 1 or
* greater otherwise.
*
* This function just shuts down the error module. It is also called by
* eina_shutdown(). It returns 0 when it is called the same number of
* times than eina_convert_init().
*/
EAPI int
eina_convert_shutdown(void)
{
_eina_convert_init_count--;
if (_eina_convert_init_count > 0) goto shutdown_out;
eina_safety_checks_shutdown();
eina_log_domain_unregister(_eina_convert_log_dom);
eina_log_shutdown();
eina_error_shutdown();
shutdown_out:
return _eina_convert_init_count;
}
/*
* Come from the second edition of The C Programming Language ("K&R2") on page 64
*/
/**
* @brief Convert an integer number to a string in decimal base.
*
* @param n The integer to convert.
* @param s The buffer to store the converted integer.
* @return The length of the string, including the nul terminated
* character.
*
* This function converts @p n to a nul terminated string. The
* converted string is in decimal base. As no check is done, @p s must
* be a buffer that is sufficiently large to store the integer.
*
* The returned value is the length os the string, including the nul
* terminated character.
*/
EAPI int
eina_convert_itoa(int n, char *s)
{
int i = 0;
int r = 0;
EINA_SAFETY_ON_NULL_RETURN_VAL(s, 0);
if (n < 0)
{
n = -n;
*s++ = '-';
r = 1;
}
do {
s[i++] = n % 10 + '0';
} while ((n /= 10) > 0);
s[i] = '\0';
reverse(s, i);
return i + r;
}
/**
* @brief Convert an integer number to a string in hexadecimal base.
*
* @param n The integer to convert.
* @param s The buffer to store the converted integer.
* @return The length of the string, including the nul terminated
* character.
*
* This function converts @p n to a nul terminated string. The
* converted string is in hexadecimal base and the alphabetical
* cyphers are in lower case. As no check is done, @p s must be a
* buffer that is sufficiently large to store the integer.
*
* The returned value is the length os the string, including the nul
* terminated character.
*/
EAPI int
eina_convert_xtoa(unsigned int n, char *s)
{
int i;
EINA_SAFETY_ON_NULL_RETURN_VAL(s, 0);
i = 0;
do {
s[i++] = look_up_table[n & 0xF];
} while ((n >>= 4) > 0);
s[i] = '\0';
reverse(s, i);
return i;
}
/**
* @brief Convert a string to a double
*
* @param src The string to convert.
* @param length The length of the string.
* @param m The mantisse.
* @param e The exponent.
* @return #EINA_TRUE on success, #EINA_FALSE otherwise.
*
* This function converts the string @p s of length @p length that
* represent a double in hexadecimal base to a double. It is used to
* replace the use of snprintf() with the \%a modifier, which is
* missing on some platform (like Windows (tm) or OpenBSD).
*
* The string must have the following format:
*
* @code
* [-]0xh.hhhhhp[+-]e
* @endcode
*
* where the h are the hexadecimal cyphers of the mantiss and e the
* exponent (a decimal number). If n is the number of cypers after the
* point, the returned mantiss and exponents are:
*
* @code
* mantiss : [-]hhhhhh
* exponent : 2^([+-]e - 4 * n)
* @endcode
*
* The mantiss and exponent are stored in the buffers pointed
* respectively by @p m and @p e.
*
* If the string is invalid, the error is set to:
*
* @li #EINA_ERROR_CONVERT_0X_NOT_FOUND if no 0x is found,
* @li #EINA_ERROR_CONVERT_P_NOT_FOUND if no p is found,
* @li #EINA_ERROR_CONVERT_OUTRUN_STRING_LENGTH if @p length is not
* correct.
*
* In those cases, #EINA_FALSE is returned, otherwise #EINA_TRUE is
* returned.
*/
EAPI Eina_Bool
eina_convert_atod(const char *src, int length, long long *m, long *e)
{
const char *str = src;
long long mantisse;
long exponent;
int nbr_decimals = 0;
int sign = 1;
EINA_SAFETY_ON_NULL_RETURN_VAL(src, EINA_FALSE);
EINA_SAFETY_ON_NULL_RETURN_VAL(m, EINA_FALSE);
EINA_SAFETY_ON_NULL_RETURN_VAL(e, EINA_FALSE);
if (length <= 0) goto on_length_error;
/* Compute the mantisse. */
if (*str == '-')
{
sign = -1;
str++;
length--;
}
if (length <= 2) goto on_length_error;
if (strncmp(str, "0x", 2))
{
eina_error_set(EINA_ERROR_CONVERT_0X_NOT_FOUND);
DBG("'0x' not found in '%s'", src);
return EINA_FALSE;
}
str += 2;
length -= 2;
mantisse = HEXA_TO_INT(*str);
str++;
length--; if (length <= 0) goto on_length_error;
if (*str == '.')
{
for (str++, length--;
length > 0 && *str != 'p';
++str, --length, ++nbr_decimals)
{
mantisse <<= 4;
mantisse += HEXA_TO_INT(*str);
}
}
if (sign < 0) mantisse = -mantisse;
/* Compute the exponent. */
if (*str != 'p')
{
eina_error_set(EINA_ERROR_CONVERT_P_NOT_FOUND);
DBG("'p' not found in '%s'", src);
return EINA_FALSE;
}
sign = +1;
str++;
length--; if (length <= 0) goto on_length_error;
if (strchr("-+", *str))
{
sign = (*str == '-') ? -1 : +1;
str++; length--;
}
for (exponent = 0; length > 0 && *str != '\0'; ++str, --length)
{
exponent *= 10;
exponent += *str - '0';
}
if (length < 0) goto on_length_error;
if (sign < 0)
exponent = -exponent;
*m = mantisse;
*e = exponent - (nbr_decimals << 2);
return EINA_TRUE;
on_length_error:
eina_error_set(EINA_ERROR_CONVERT_OUTRUN_STRING_LENGTH);
return EINA_FALSE;
}
/**
* @brief Convert a double to a string
*
* @param d The double to convert.
* @param des The destination buffer to store the converted double.
* @return #EINA_TRUE on success, #EINA_FALSE otherwise.
*
* This function converts the double @p d to a string. The string is
* stored in the buffer pointed by @p des and must be sufficiently
* large to contain the converted double. The returned string is
* terminated and has the following format:
*
* @code
* [-]0xh.hhhhhp[+-]e
* @endcode
*
* where the h are the hexadecimal cyphers of the mantiss and e the
* exponent (a decimal number).
*
* The returned value is the length of the string, including the nul
* character.
*/
EAPI int
eina_convert_dtoa(double d, char *des)
{
int length = 0;
int p;
int i;
EINA_SAFETY_ON_NULL_RETURN_VAL(des, EINA_FALSE);
if (d < 0.0)
{
*(des++) = '-';
d = -d;
length++;
}
d = frexp(d, &p);
if (p)
{
d *= 2;
p -= 1;
}
*(des++) = '0';
*(des++) = 'x';
*(des++) = look_up_table[(size_t)d];
*(des++) = '.';
length += 4;
for (i = 0; i < 16; i++, length++)
{
d -= floor(d);
d *= 16;
*(des++) = look_up_table[(size_t)d];
}
while (*(des - 1) == '0')
{
des--;
length--;
}
if (*(des - 1) == '.')
{
des--;
length--;
}
*(des++) = 'p';
if (p < 0)
{
*(des++) = '-';
p = -p;
}
else
*(des++) = '+';
length += 2;
return length + eina_convert_itoa(p, des);
}
/**
* @}
*/