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/*
* base-64 encoding pinched from lynx2-7-2, who pinched it from rpem.
* Originally written by Mark Riordan 12 August 1990 and 17 Feb 1991
* and placed in the public domain.
*
* Dug Song <dugsong@UMICH.EDU>
*/
#include "includes.h"
#include "xmalloc.h"
char six2pr[64] = {
'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M',
'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',
'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm',
'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',
'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/'
};
unsigned char pr2six[256];
int
uuencode(unsigned char *bufin, unsigned int nbytes, char *bufcoded)
{
/* ENC is the basic 1 character encoding function to make a char printing */
#define ENC(c) six2pr[c]
register char *outptr = bufcoded;
unsigned int i;
for (i = 0; i < nbytes; i += 3) {
*(outptr++) = ENC(*bufin >> 2); /* c1 */
*(outptr++) = ENC(((*bufin << 4) & 060) | ((bufin[1] >> 4) & 017)); /* c2 */
*(outptr++) = ENC(((bufin[1] << 2) & 074) | ((bufin[2] >> 6) & 03)); /* c3 */
*(outptr++) = ENC(bufin[2] & 077); /* c4 */
bufin += 3;
}
if (i == nbytes + 1) {
outptr[-1] = '=';
} else if (i == nbytes + 2) {
outptr[-1] = '=';
outptr[-2] = '=';
} else if (i == nbytes) {
*(outptr++) = '=';
}
*outptr = '\0';
return (outptr - bufcoded);
}
int
uudecode(const char *bufcoded, unsigned char *bufplain, int outbufsize)
{
/* single character decode */
#define DEC(c) pr2six[(unsigned char)c]
#define MAXVAL 63
static int first = 1;
int nbytesdecoded, j;
const char *bufin = bufcoded;
register unsigned char *bufout = bufplain;
register int nprbytes;
/* If this is the first call, initialize the mapping table. */
if (first) {
first = 0;
for (j = 0; j < 256; j++)
pr2six[j] = MAXVAL + 1;
for (j = 0; j < 64; j++)
pr2six[(unsigned char) six2pr[j]] = (unsigned char) j;
}
/* Strip leading whitespace. */
while (*bufcoded == ' ' || *bufcoded == '\t')
bufcoded++;
/*
* Figure out how many characters are in the input buffer. If this
* would decode into more bytes than would fit into the output
* buffer, adjust the number of input bytes downwards.
*/
bufin = bufcoded;
while (DEC(*(bufin++)) <= MAXVAL)
;
nprbytes = bufin - bufcoded - 1;
nbytesdecoded = ((nprbytes + 3) / 4) * 3;
if (nbytesdecoded > outbufsize)
nprbytes = (outbufsize * 4) / 3;
bufin = bufcoded;
while (nprbytes > 0) {
*(bufout++) = (unsigned char) (DEC(*bufin) << 2 | DEC(bufin[1]) >> 4);
*(bufout++) = (unsigned char) (DEC(bufin[1]) << 4 | DEC(bufin[2]) >> 2);
*(bufout++) = (unsigned char) (DEC(bufin[2]) << 6 | DEC(bufin[3]));
bufin += 4;
nprbytes -= 4;
}
if (nprbytes & 03) {
if (DEC(bufin[-2]) > MAXVAL)
nbytesdecoded -= 2;
else
nbytesdecoded -= 1;
}
return (nbytesdecoded);
}
void
dump_base64(FILE *fp, unsigned char *data, int len)
{
unsigned char *buf = xmalloc(2*len);
int i, n;
n = uuencode(data, len, buf);
for (i = 0; i < n; i++) {
fprintf(fp, "%c", buf[i]);
if (i % 70 == 69)
fprintf(fp, "\n");
}
if (i % 70 != 69)
fprintf(fp, "\n");
xfree(buf);
}
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