3
0

uuencode.c 2.0 KB

1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071
  1. /* vi: set sw=4 ts=4: */
  2. /*
  3. * Copyright 2006 Rob Landley <rob@landley.net>
  4. *
  5. * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
  6. */
  7. #include "libbb.h"
  8. /* Conversion table. for base 64 */
  9. const char bb_uuenc_tbl_base64[65 + 2] ALIGN1 = {
  10. 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H',
  11. 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
  12. 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X',
  13. 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f',
  14. 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n',
  15. 'o', 'p', 'q', 'r', 's', 't', 'u', 'v',
  16. 'w', 'x', 'y', 'z', '0', '1', '2', '3',
  17. '4', '5', '6', '7', '8', '9', '+', '/',
  18. '=' /* termination character */,
  19. '\n', '\0' /* needed for uudecode.c */
  20. };
  21. const char bb_uuenc_tbl_std[65] ALIGN1 = {
  22. '`', '!', '"', '#', '$', '%', '&', '\'',
  23. '(', ')', '*', '+', ',', '-', '.', '/',
  24. '0', '1', '2', '3', '4', '5', '6', '7',
  25. '8', '9', ':', ';', '<', '=', '>', '?',
  26. '@', 'A', 'B', 'C', 'D', 'E', 'F', 'G',
  27. 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O',
  28. 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W',
  29. 'X', 'Y', 'Z', '[', '\\', ']', '^', '_',
  30. '`' /* termination character */
  31. };
  32. /*
  33. * Encode bytes at S of length LENGTH to uuencode or base64 format and place it
  34. * to STORE. STORE will be 0-terminated, and must point to a writable
  35. * buffer of at least 1+BASE64_LENGTH(length) bytes.
  36. * where BASE64_LENGTH(len) = (4 * ((LENGTH + 2) / 3))
  37. */
  38. void FAST_FUNC bb_uuencode(char *p, const void *src, int length, const char *tbl)
  39. {
  40. const unsigned char *s = src;
  41. /* Transform the 3x8 bits to 4x6 bits */
  42. while (length > 0) {
  43. unsigned s1, s2;
  44. /* Are s[1], s[2] valid or should be assumed 0? */
  45. s1 = s2 = 0;
  46. length -= 3; /* can be >=0, -1, -2 */
  47. if (length >= -1) {
  48. s1 = s[1];
  49. if (length >= 0)
  50. s2 = s[2];
  51. }
  52. *p++ = tbl[s[0] >> 2];
  53. *p++ = tbl[((s[0] & 3) << 4) + (s1 >> 4)];
  54. *p++ = tbl[((s1 & 0xf) << 2) + (s2 >> 6)];
  55. *p++ = tbl[s2 & 0x3f];
  56. s += 3;
  57. }
  58. /* Zero-terminate */
  59. *p = '\0';
  60. /* If length is -2 or -1, pad last char or two */
  61. while (length) {
  62. *--p = tbl[64];
  63. length++;
  64. }
  65. }