-static byte dtable[SIZ]; /* base64 encode / decode table */
-
-/*
- * CtdlDecodeBase64() and encode_base64() are adaptations of code by
- * John Walker, found in full in the file "base64.c" included with the Citadel
- * server. The difference between those functions and these is that
- * these are intended to encode/decode small string buffers, and those are
- * intended to encode/decode entire MIME parts.
- */
-
-void encode_base64(char *dest, char *source)
-{
- int i, hiteof = FALSE;
- int spos = 0;
- int dpos = 0;
-
- /* Fill dtable with character encodings. */
-
- for (i = 0; i < 26; i++) {
- dtable[i] = 'A' + i;
- dtable[26 + i] = 'a' + i;
- }
- for (i = 0; i < 10; i++) {
- dtable[52 + i] = '0' + i;
- }
- dtable[62] = '+';
- dtable[63] = '/';
-
- while (!hiteof) {
- byte igroup[3], ogroup[4];
- int c, n;
-
- igroup[0] = igroup[1] = igroup[2] = 0;
- for (n = 0; n < 3; n++) {
- c = source[spos++];
- if (c == 0) {
- hiteof = TRUE;
- break;
- }
- igroup[n] = (byte) c;
- }
- if (n > 0) {
- ogroup[0] = dtable[igroup[0] >> 2];
- ogroup[1] = dtable[((igroup[0] & 3) << 4) | (igroup[1] >> 4)];
- ogroup[2] = dtable[((igroup[1] & 0xF) << 2) | (igroup[2] >> 6)];
- ogroup[3] = dtable[igroup[2] & 0x3F];
-
- /* Replace characters in output stream with "=" pad
- characters if fewer than three characters were
- read from the end of the input stream. */
-
- if (n < 3) {
- ogroup[3] = '=';
- if (n < 2) {
- ogroup[2] = '=';
- }
- }
- for (i = 0; i < 4; i++) {
- dest[dpos++] = ogroup[i];
- dest[dpos] = 0;
- }
- }
- }
-}
-
-
-/*
- * Convert base64-encoded to binary. Returns the length of the decoded data.
- * It will stop after reading 'length' bytes.
- */
-int CtdlDecodeBase64(char *dest, char *source, size_t length)
-{
- int i, c;
- int dpos = 0;
- int spos = 0;
-
- for (i = 0; i < 255; i++) {
- dtable[i] = 0x80;
- }
- for (i = 'A'; i <= 'Z'; i++) {
- dtable[i] = 0 + (i - 'A');
- }
- for (i = 'a'; i <= 'z'; i++) {
- dtable[i] = 26 + (i - 'a');
- }
- for (i = '0'; i <= '9'; i++) {
- dtable[i] = 52 + (i - '0');
- }
- dtable['+'] = 62;
- dtable['/'] = 63;
- dtable['='] = 0;
-
- /*CONSTANTCONDITION*/
- while (TRUE) {
- byte a[4], b[4], o[3];
-
- for (i = 0; i < 4; i++) {
- if (spos >= length) {
- return(dpos);
- }
- c = source[spos++];
-
- if (c == 0) {
- if (i > 0) {
- return(dpos);
- }
- return(dpos);
- }
- if (dtable[c] & 0x80) {
- /* Ignoring errors: discard invalid character. */
- i--;
- continue;
- }
- a[i] = (byte) c;
- b[i] = (byte) dtable[c];
- }
- o[0] = (b[0] << 2) | (b[1] >> 4);
- o[1] = (b[1] << 4) | (b[2] >> 2);
- o[2] = (b[2] << 6) | b[3];
- i = a[2] == '=' ? 1 : (a[3] == '=' ? 2 : 3);
- if (i>=1) dest[dpos++] = o[0];
- if (i>=2) dest[dpos++] = o[1];
- if (i>=3) dest[dpos++] = o[2];
- dest[dpos] = 0;
- if (i < 3) {
- return(dpos);
- }
- }
-}
-
-