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/* l64a - convert long to radix-64 ascii string
*
* Conversion is performed on at most 32-bits of input value starting
* from least significant bits to the most significant bits.
*
* The routine splits the input value into groups of 6 bits for up to
* 32 bits of input. This means that the last group may be 2 bits
* (bits 30 and 31).
*
* Each group of 6 bits forms a value from 0-63 which is converted into
* a character as follows:
* 0 = '.'
* 1 = '/'
* 2-11 = '0' to '9'
* 12-37 = 'A' to 'Z'
* 38-63 = 'a' to 'z'
*
* When the remaining bits are zero or all 32 bits have been translated,
* a nul terminator is appended to the resulting string. An input value of
* 0 results in an empty string.
*/
#include <_ansi.h>
#include <stdlib.h>
#include <reent.h>
static const char R64_ARRAY[] = "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
char *
_DEFUN (l64a, (value),
long value)
{
return _l64a_r (_REENT, value);
}
char *
_DEFUN (_l64a_r, (rptr, value),
struct _reent *rptr _AND
long value)
{
char *ptr;
char *result;
int i, index;
unsigned long tmp = (unsigned long)value & 0xffffffff;
_REENT_CHECK_MISC(rptr);
result = _REENT_L64A_BUF(rptr);
ptr = result;
for (i = 0; i < 6; ++i)
{
if (tmp == 0)
{
*ptr = '\0';
break;
}
index = tmp & (64 - 1);
*ptr++ = R64_ARRAY[index];
tmp >>= 6;
}
return result;
}
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