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/* this base64 variant was "borrowed" from MUTT, which in turn
borrowed from fetchmail.
Dave stripped it down and added the cdindex-specific charmap.
You are in a twisty maze of copyright notices, all different.
(This is GPL'd, by the way.)
*/
/*
* This code is heavily modified from fetchmail (also GPL'd, of
* course) by Brendan Cully <brendan@kublai.com>.
*
* Original copyright notice:
*
* The code in the fetchmail distribution is Copyright 1997 by Eric
* S. Raymond. Portions are also copyrighted by Carl Harris, 1993
* and 1995. Copyright retained for the purpose of protecting free
* redistribution of source.
*
*/
#include <sys/types.h>
#include <unistd.h>
/* raw bytes to null-terminated base 64 string */
void bin_to_base64 (unsigned char *out, const unsigned char *in, size_t len,
size_t olen) {
const char B64Chars[65] =
"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789._-" ;
while (len >= 3 && olen > 10) {
*out++ = B64Chars[in[0] >> 2];
*out++ = B64Chars[((in[0] << 4) & 0x30) | (in[1] >> 4)];
*out++ = B64Chars[((in[1] << 2) & 0x3c) | (in[2] >> 6)];
*out++ = B64Chars[in[2] & 0x3f];
olen -= 4;
len -= 3;
in += 3;
}
/* clean up remainder */
if (len > 0 && olen > 4) {
unsigned char fragment;
*out++ = B64Chars[in[0] >> 2];
fragment = (in[0] << 4) & 0x30;
if (len > 1)
fragment |= in[1] >> 4;
*out++ = B64Chars[fragment];
*out++ = (len < 2) ? '=' : B64Chars[(in[1] << 2) & 0x3c];
*out++ = '-';
}
*out = '\0';
}
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