| 1 | #include "stralloc.h" |
| 2 | #include "strerr.h" |
| 3 | #include "uint32.h" |
| 4 | #include "errtxt.h" |
| 5 | |
| 6 | /* Characters and translation as per rfc2047. */ |
| 7 | static char char64table[128] = { |
| 8 | -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, |
| 9 | -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, |
| 10 | -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,62, -1,-1,-1,63, |
| 11 | 52,53,54,55, 56,57,58,59, 60,61,-1,-1, -1,-1,-1,-1, |
| 12 | -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10, 11,12,13,14, |
| 13 | 15,16,17,18, 19,20,21,22, 23,24,25,-1, -1,-1,-1,-1, |
| 14 | -1,26,27,28, 29,30,31,32, 33,34,35,36, 37,38,39,40, |
| 15 | 41,42,43,44, 45,46,47,48, 49,50,51,-1, -1,-1,-1,-1 |
| 16 | }; |
| 17 | |
| 18 | #define char64enc(c) (((c) & 0x80) ? -1 : char64table[(c)]) |
| 19 | |
| 20 | static void die_nomem(fatal) |
| 21 | char *fatal; |
| 22 | { |
| 23 | strerr_die2x(111,fatal,ERR_NOMEM); |
| 24 | } |
| 25 | |
| 26 | void decodeB(cpfrom,n,outdata,fatal) |
| 27 | char *cpfrom; |
| 28 | unsigned int n; |
| 29 | stralloc *outdata; |
| 30 | char *fatal; |
| 31 | /* does B decoding of the string pointed to by cpfrom up to the character */ |
| 32 | /* before the one pointed to by cpnext, and appends the results to mimeline*/ |
| 33 | { |
| 34 | uint32 hold32; |
| 35 | char holdch[4] = "???"; |
| 36 | int i,j; |
| 37 | char c; /* needs to be signed */ |
| 38 | char *cp, *cpnext; |
| 39 | |
| 40 | cp = cpfrom; |
| 41 | cpnext = cp + n; |
| 42 | i = 0; |
| 43 | hold32 = 0L; |
| 44 | if (!stralloc_readyplus(outdata,n)) die_nomem(fatal); |
| 45 | for (;;) { |
| 46 | if (i == 4) { |
| 47 | for (j = 2; j >= 0; --j) { |
| 48 | holdch[j] = hold32 & 0xff; |
| 49 | hold32 = hold32 >> 8; |
| 50 | } |
| 51 | if (!stralloc_cats(outdata,holdch)) die_nomem(fatal); |
| 52 | if (cp >= cpnext) |
| 53 | break; |
| 54 | hold32 = 0L; |
| 55 | i = 0; |
| 56 | } |
| 57 | if (cp >= cpnext) { /* pad */ |
| 58 | c = 0; |
| 59 | } else { |
| 60 | c = char64enc(*cp); |
| 61 | ++cp; |
| 62 | } |
| 63 | if (c < 0) /* ignore illegal characters */ |
| 64 | continue; |
| 65 | else { |
| 66 | hold32 = (hold32 << 6) | (c & 0x7f); |
| 67 | ++i; |
| 68 | } |
| 69 | } |
| 70 | } |
| 71 | |