Tizen Native API
|
Functions | |
int | eina_convert_itoa (int n, char *s) |
Convert an integer number to a string in decimal base. | |
int | eina_convert_xtoa (unsigned int n, char *s) |
Convert an integer number to a string in hexadecimal base. | |
int | eina_convert_dtoa (double d, char *des) |
Convert a double to a string. | |
Eina_Bool | eina_convert_atod (const char *src, int length, long long *m, long *e) |
Convert a string to a double. | |
int | eina_convert_fptoa (Eina_F32p32 fp, char *des) |
Convert a 32.32 fixed point number to a string. | |
Eina_Bool | eina_convert_atofp (const char *src, int length, Eina_F32p32 *fp) |
Convert a string to a 32.32 fixed point number. |
These functions allow you to convert integer or real numbers to string or conversely.
To use these functions, Eina must be initialized first, and Eina must be shut down when eina is not used anymore.
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 buffer sufficiently large to store all the cyphers.
Here is an example of use:
#include <stdlib.h> #include <stdio.h> #include <Eina.h> int main(void) { char tmp[128]; if (!eina_init()) { printf ("Error during the initialization of eina.\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_shutdown(); return EXIT_SUCCESS; }
Compile this code with the following command:
gcc -Wall -o test_eina_convert test_eina.c `pkg-config --cflags --libs eina`
- Note:
- The alphabetical cyphers are in lower case.
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 has the following format (which is the result obtained with snprintf() and the %a modifier):
[-]0xh.hhhhhp[+-]e
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:
mantiss : [-]hhhhhh exponent : 2^([+-]e - 4 * n)
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 example of use:
#include <stdlib.h> #include <stdio.h> #include <math.h> #include <Eina.h> int main(void) { char tmp[128]; long long int m = 0; long int e = 0; double r; if (!eina_init()) { printf ("Error during the initialization of eina.\n"); return EXIT_FAILURE; } printf("initial value : 40.56\n"); eina_convert_dtoa(40.56, tmp); printf("result dtoa : %s\n", tmp); eina_convert_atod(tmp, 128, &m, &e); r = ldexp((double)m, e); printf("result atod : %f\n", r); eina_shutdown(); return EXIT_SUCCESS; }
Compile this code with the following command:
gcc -Wall -o test_eina_convert test_eina.c `pkg-config --cflags --libs eina` -lm
Function Documentation
Eina_Bool eina_convert_atod | ( | const char * | src, |
int | length, | ||
long long * | m, | ||
long * | e | ||
) |
Convert a string to a double.
- Since :
- 2.3
- Parameters:
-
[in] src The string to convert. [in] length The length of the string. [out] m The mantisse. [out] e The exponent.
- Returns:
- EINA_TRUE on success, EINA_FALSE otherwise.
- Remarks:
- This function converts the string
s
of lengthlength
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:
[-]0xh.hhhhhp[+-]e
- Remarks:
- 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:
mantiss : [-]hhhhhh exponent : 2^([+-]e - 4 * n)
- Remarks:
- The mantiss and exponent are stored in the buffers pointed respectively by
m
ande
. - If the string is invalid EINA_FALSE is returned, otherwise EINA_TRUE is returned.
Eina_Bool eina_convert_atofp | ( | const char * | src, |
int | length, | ||
Eina_F32p32 * | fp | ||
) |
Convert a string to a 32.32 fixed point number.
- Since :
- 2.3
- Parameters:
-
[in] src The string to convert. [in] length The length of the string. [out] fp The fixed point number.
- Returns:
- EINA_TRUE on success, EINA_FALSE otherwise.
- Remarks:
- This function converts the string
src
of lengthlength
that represent a double in hexadecimal base to a 32.32 fixed point number stored infp
. The function always tries to convert the string with eina_convert_atod(). - The string must have the following format:
[-]0xh.hhhhhp[+-]e
- Remarks:
- 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:
mantiss : [-]hhhhhh exponent : 2^([+-]e - 4 * n)
- Remarks:
- The mantiss and exponent are stored in the buffers pointed respectively by
m
ande
. -
If the string is invalid, EINA_FALSE is returned, otherwise
fp
is computed and EINA_TRUE is returned. - The code uses eina_convert_atod() and do the correct bit shift to compute the fixed point number.
int eina_convert_dtoa | ( | double | d, |
char * | des | ||
) |
Convert a double to a string.
- Since :
- 2.3
- Parameters:
-
[in] d The double to convert. [out] des The destination buffer to store the converted double.
- Returns:
- EINA_TRUE on success, EINA_FALSE otherwise.
- Remarks:
- This function converts the double
d
to a string. The string is stored in the buffer pointed bydes
and must be sufficiently large to contain the converted double. The returned string is nul terminated and has the following format:
[-]0xh.hhhhhp[+-]e
- Remarks:
- 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.
int eina_convert_fptoa | ( | Eina_F32p32 | fp, |
char * | des | ||
) |
Convert a 32.32 fixed point number to a string.
- Since :
- 2.3
- Parameters:
-
[in] fp The fixed point number to convert. [out] des The destination buffer to store the converted fixed point number.
- Returns:
- EINA_TRUE on success, EINA_FALSE otherwise.
- Remarks:
- This function converts the 32.32 fixed point number
fp
to a string. The string is stored in the buffer pointed bydes
and must be sufficiently large to contain the converted fixed point number. The returned string is terminated and has the following format:
[-]0xh.hhhhhp[+-]e
- Remarks:
- 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.
- The code is the same than eina_convert_dtoa() except that it implements the frexp() function for fixed point numbers and does some optimisations.
int eina_convert_itoa | ( | int | n, |
char * | s | ||
) |
Convert an integer number to a string in decimal base.
- Since :
- 2.3
- Parameters:
-
[in] n The integer to convert. [out] s The buffer to store the converted integer.
- Returns:
- The length of the string, including the nul terminated character.
- Remarks:
- This function converts
n
to a nul terminated string. The converted string is in decimal base. As no check is done,s
must be a buffer that is sufficiently large to store the integer. - The returned value is the length of the string, including the nul terminated character.
int eina_convert_xtoa | ( | unsigned int | n, |
char * | s | ||
) |
Convert an integer number to a string in hexadecimal base.
- Since :
- 2.3
- Parameters:
-
[in] n The integer to convert. [out] s The buffer to store the converted integer.
- Returns:
- The length of the string, including the nul terminated character.
- Remarks:
- This function converts
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,s
must be a buffer that is sufficiently large to store the integer. - The returned value is the length of the string, including the nul terminated character.
Variable Documentation
Not used, perhaps a placeholder? Defined as 0 in eina_convert.c
Not used, perhaps a placeholder? Defined as 0 in eina_convert.c
Not used, perhaps a placeholder? Defined as 0 in eina_convert.c