Jack Jansen | 7278119 | 1995-08-07 14:34:15 +0000 | [diff] [blame] | 1 | /*********************************************************** |
| 2 | Copyright 1991, 1992, 1993, 1994 by Stichting Mathematisch Centrum, |
| 3 | Amsterdam, The Netherlands. |
| 4 | |
| 5 | All Rights Reserved |
| 6 | |
| 7 | Permission to use, copy, modify, and distribute this software and its |
| 8 | documentation for any purpose and without fee is hereby granted, |
| 9 | provided that the above copyright notice appear in all copies and that |
| 10 | both that copyright notice and this permission notice appear in |
| 11 | supporting documentation, and that the names of Stichting Mathematisch |
| 12 | Centrum or CWI not be used in advertising or publicity pertaining to |
| 13 | distribution of the software without specific, written prior permission. |
| 14 | |
| 15 | STICHTING MATHEMATISCH CENTRUM DISCLAIMS ALL WARRANTIES WITH REGARD TO |
| 16 | THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND |
| 17 | FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH CENTRUM BE LIABLE |
| 18 | FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
| 19 | WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN |
| 20 | ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT |
| 21 | OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. |
| 22 | |
| 23 | ******************************************************************/ |
| 24 | |
| 25 | /* |
| 26 | ** Routines to represent binary data in ASCII and vice-versa |
| 27 | ** |
| 28 | ** This module currently supports the following encodings: |
| 29 | ** uuencode: |
| 30 | ** each line encodes 45 bytes (except possibly the last) |
| 31 | ** First char encodes (binary) length, rest data |
| 32 | ** each char encodes 6 bits, as follows: |
| 33 | ** binary: 01234567 abcdefgh ijklmnop |
| 34 | ** ascii: 012345 67abcd efghij klmnop |
| 35 | ** ASCII encoding method is "excess-space": 000000 is encoded as ' ', etc. |
| 36 | ** short binary data is zero-extended (so the bits are always in the |
| 37 | ** right place), this does *not* reflect in the length. |
| 38 | ** hqx: |
| 39 | ** File starts with introductory text, real data starts and ends |
| 40 | ** with colons. |
| 41 | ** Data consists of three similar parts: info, datafork, resourcefork. |
| 42 | ** Each part is protected (at the end) with a 16-bit crc |
| 43 | ** The binary data is run-length encoded, and then ascii-fied: |
| 44 | ** binary: 01234567 abcdefgh ijklmnop |
| 45 | ** ascii: 012345 67abcd efghij klmnop |
| 46 | ** ASCII encoding is table-driven, see the code. |
| 47 | ** Short binary data results in the runt ascii-byte being output with |
| 48 | ** the bits in the right place. |
| 49 | ** |
| 50 | ** While I was reading dozens of programs that encode or decode the formats |
| 51 | ** here (documentation? hihi:-) I have formulated Jansen's Observation: |
| 52 | ** |
| 53 | ** Programs that encode binary data in ASCII are written in |
| 54 | ** such a style that they are as unreadable as possible. Devices used |
| 55 | ** include unnecessary global variables, burying important tables |
| 56 | ** in unrelated sourcefiles, putting functions in include files, |
| 57 | ** using seemingly-descriptive variable names for different purposes, |
| 58 | ** calls to empty subroutines and a host of others. |
| 59 | ** |
| 60 | ** I have attempted to break with this tradition, but I guess that that |
| 61 | ** does make the performance sub-optimal. Oh well, too bad... |
| 62 | ** |
| 63 | ** Jack Jansen, CWI, July 1995. |
| 64 | */ |
| 65 | |
| 66 | |
| 67 | #include "Python.h" |
| 68 | |
| 69 | static PyObject *Error; |
| 70 | static PyObject *Incomplete; |
| 71 | |
| 72 | /* |
| 73 | ** hqx lookup table, ascii->binary. |
| 74 | */ |
| 75 | |
| 76 | #define RUNCHAR 0x90 |
| 77 | |
| 78 | #define DONE 0x7F |
| 79 | #define SKIP 0x7E |
| 80 | #define FAIL 0x7D |
| 81 | |
| 82 | static unsigned char table_a2b_hqx[256] = { |
| 83 | /* ^@ ^A ^B ^C ^D ^E ^F ^G */ |
| 84 | /* 0*/ FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, |
| 85 | /* \b \t \n ^K ^L \r ^N ^O */ |
| 86 | /* 1*/ FAIL, FAIL, SKIP, FAIL, FAIL, SKIP, FAIL, FAIL, |
| 87 | /* ^P ^Q ^R ^S ^T ^U ^V ^W */ |
| 88 | /* 2*/ FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, |
| 89 | /* ^X ^Y ^Z ^[ ^\ ^] ^^ ^_ */ |
| 90 | /* 3*/ FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, |
| 91 | /* ! " # $ % & ' */ |
| 92 | /* 4*/ FAIL, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, |
| 93 | /* ( ) * + , - . / */ |
| 94 | /* 5*/ 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, FAIL, FAIL, |
| 95 | /* 0 1 2 3 4 5 6 7 */ |
| 96 | /* 6*/ 0x0D, 0x0E, 0x0F, 0x10, 0x11, 0x12, 0x13, FAIL, |
| 97 | /* 8 9 : ; < = > ? */ |
| 98 | /* 7*/ 0x14, 0x15, DONE, FAIL, FAIL, FAIL, FAIL, FAIL, |
| 99 | /* @ A B C D E F G */ |
| 100 | /* 8*/ 0x16, 0x17, 0x18, 0x19, 0x1A, 0x1B, 0x1C, 0x1D, |
| 101 | /* H I J K L M N O */ |
| 102 | /* 9*/ 0x1E, 0x1F, 0x20, 0x21, 0x22, 0x23, 0x24, FAIL, |
| 103 | /* P Q R S T U V W */ |
| 104 | /*10*/ 0x25, 0x26, 0x27, 0x28, 0x29, 0x2A, 0x2B, FAIL, |
| 105 | /* X Y Z [ \ ] ^ _ */ |
| 106 | /*11*/ 0x2C, 0x2D, 0x2E, 0x2F, FAIL, FAIL, FAIL, FAIL, |
| 107 | /* ` a b c d e f g */ |
| 108 | /*12*/ 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, FAIL, |
| 109 | /* h i j k l m n o */ |
| 110 | /*13*/ 0x37, 0x38, 0x39, 0x3A, 0x3B, 0x3C, FAIL, FAIL, |
| 111 | /* p q r s t u v w */ |
| 112 | /*14*/ 0x3D, 0x3E, 0x3F, FAIL, FAIL, FAIL, FAIL, FAIL, |
| 113 | /* x y z { | } ~ ^? */ |
| 114 | /*15*/ FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, |
| 115 | /*16*/ FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, |
| 116 | FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, |
| 117 | FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, |
| 118 | FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, |
| 119 | FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, |
| 120 | FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, |
| 121 | FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, |
| 122 | FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, |
| 123 | FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, |
| 124 | FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, |
| 125 | FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, |
| 126 | FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, |
| 127 | FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, |
| 128 | FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, |
| 129 | FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, |
| 130 | FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, |
| 131 | }; |
| 132 | |
| 133 | static unsigned char table_b2a_hqx[] = |
| 134 | "!\"#$%&'()*+,-012345689@ABCDEFGHIJKLMNPQRSTUVXYZ[`abcdefhijklmpqr"; |
| 135 | |
| 136 | static unsigned short crctab_hqx[256] = { |
| 137 | 0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7, |
| 138 | 0x8108, 0x9129, 0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef, |
| 139 | 0x1231, 0x0210, 0x3273, 0x2252, 0x52b5, 0x4294, 0x72f7, 0x62d6, |
| 140 | 0x9339, 0x8318, 0xb37b, 0xa35a, 0xd3bd, 0xc39c, 0xf3ff, 0xe3de, |
| 141 | 0x2462, 0x3443, 0x0420, 0x1401, 0x64e6, 0x74c7, 0x44a4, 0x5485, |
| 142 | 0xa56a, 0xb54b, 0x8528, 0x9509, 0xe5ee, 0xf5cf, 0xc5ac, 0xd58d, |
| 143 | 0x3653, 0x2672, 0x1611, 0x0630, 0x76d7, 0x66f6, 0x5695, 0x46b4, |
| 144 | 0xb75b, 0xa77a, 0x9719, 0x8738, 0xf7df, 0xe7fe, 0xd79d, 0xc7bc, |
| 145 | 0x48c4, 0x58e5, 0x6886, 0x78a7, 0x0840, 0x1861, 0x2802, 0x3823, |
| 146 | 0xc9cc, 0xd9ed, 0xe98e, 0xf9af, 0x8948, 0x9969, 0xa90a, 0xb92b, |
| 147 | 0x5af5, 0x4ad4, 0x7ab7, 0x6a96, 0x1a71, 0x0a50, 0x3a33, 0x2a12, |
| 148 | 0xdbfd, 0xcbdc, 0xfbbf, 0xeb9e, 0x9b79, 0x8b58, 0xbb3b, 0xab1a, |
| 149 | 0x6ca6, 0x7c87, 0x4ce4, 0x5cc5, 0x2c22, 0x3c03, 0x0c60, 0x1c41, |
| 150 | 0xedae, 0xfd8f, 0xcdec, 0xddcd, 0xad2a, 0xbd0b, 0x8d68, 0x9d49, |
| 151 | 0x7e97, 0x6eb6, 0x5ed5, 0x4ef4, 0x3e13, 0x2e32, 0x1e51, 0x0e70, |
| 152 | 0xff9f, 0xefbe, 0xdfdd, 0xcffc, 0xbf1b, 0xaf3a, 0x9f59, 0x8f78, |
| 153 | 0x9188, 0x81a9, 0xb1ca, 0xa1eb, 0xd10c, 0xc12d, 0xf14e, 0xe16f, |
| 154 | 0x1080, 0x00a1, 0x30c2, 0x20e3, 0x5004, 0x4025, 0x7046, 0x6067, |
| 155 | 0x83b9, 0x9398, 0xa3fb, 0xb3da, 0xc33d, 0xd31c, 0xe37f, 0xf35e, |
| 156 | 0x02b1, 0x1290, 0x22f3, 0x32d2, 0x4235, 0x5214, 0x6277, 0x7256, |
| 157 | 0xb5ea, 0xa5cb, 0x95a8, 0x8589, 0xf56e, 0xe54f, 0xd52c, 0xc50d, |
| 158 | 0x34e2, 0x24c3, 0x14a0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405, |
| 159 | 0xa7db, 0xb7fa, 0x8799, 0x97b8, 0xe75f, 0xf77e, 0xc71d, 0xd73c, |
| 160 | 0x26d3, 0x36f2, 0x0691, 0x16b0, 0x6657, 0x7676, 0x4615, 0x5634, |
| 161 | 0xd94c, 0xc96d, 0xf90e, 0xe92f, 0x99c8, 0x89e9, 0xb98a, 0xa9ab, |
| 162 | 0x5844, 0x4865, 0x7806, 0x6827, 0x18c0, 0x08e1, 0x3882, 0x28a3, |
| 163 | 0xcb7d, 0xdb5c, 0xeb3f, 0xfb1e, 0x8bf9, 0x9bd8, 0xabbb, 0xbb9a, |
| 164 | 0x4a75, 0x5a54, 0x6a37, 0x7a16, 0x0af1, 0x1ad0, 0x2ab3, 0x3a92, |
| 165 | 0xfd2e, 0xed0f, 0xdd6c, 0xcd4d, 0xbdaa, 0xad8b, 0x9de8, 0x8dc9, |
| 166 | 0x7c26, 0x6c07, 0x5c64, 0x4c45, 0x3ca2, 0x2c83, 0x1ce0, 0x0cc1, |
| 167 | 0xef1f, 0xff3e, 0xcf5d, 0xdf7c, 0xaf9b, 0xbfba, 0x8fd9, 0x9ff8, |
| 168 | 0x6e17, 0x7e36, 0x4e55, 0x5e74, 0x2e93, 0x3eb2, 0x0ed1, 0x1ef0, |
| 169 | }; |
| 170 | |
| 171 | static char doc_a2b_uu[] = "(ascii) -> bin. Decode a line of uuencoded data"; |
| 172 | |
| 173 | static PyObject * |
| 174 | binascii_a2b_uu(self, args) |
| 175 | PyObject *self; |
| 176 | PyObject *args; |
| 177 | { |
| 178 | unsigned char *ascii_data, *bin_data; |
| 179 | int leftbits = 0; |
| 180 | unsigned char this_ch; |
| 181 | unsigned int leftchar = 0; |
| 182 | PyObject *rv; |
| 183 | int ascii_len, bin_len; |
| 184 | |
| 185 | if ( !PyArg_ParseTuple(args, "s#", &ascii_data, &ascii_len) ) |
| 186 | return NULL; |
| 187 | |
| 188 | /* First byte: binary data length (in bytes) */ |
| 189 | bin_len = (*ascii_data++ - ' ') & 077; |
| 190 | ascii_len--; |
| 191 | |
| 192 | /* Allocate the buffer */ |
| 193 | if ( (rv=PyString_FromStringAndSize(NULL, bin_len)) == NULL ) |
| 194 | return NULL; |
| 195 | bin_data = (unsigned char *)PyString_AsString(rv); |
| 196 | |
| 197 | for( ; bin_len > 0 ; ascii_len--, ascii_data++ ) { |
| 198 | this_ch = *ascii_data; |
| 199 | if ( this_ch == '\n' || this_ch == '\r' || ascii_len <= 0) { |
| 200 | /* |
| 201 | ** Whitespace. Assume some spaces got eaten at |
| 202 | ** end-of-line. (We check this later) |
| 203 | */ |
| 204 | this_ch = 0; |
| 205 | } else { |
| 206 | /* Check the character for legality */ |
| 207 | if ( this_ch < ' ' || this_ch > (' ' + 63)) { |
| 208 | PyErr_SetString(Error, "Illegal char"); |
| 209 | Py_DECREF(rv); |
| 210 | return NULL; |
| 211 | } |
| 212 | this_ch = (this_ch - ' ') & 077; |
| 213 | } |
| 214 | /* |
| 215 | ** Shift it in on the low end, and see if there's |
| 216 | ** a byte ready for output. |
| 217 | */ |
| 218 | leftchar = (leftchar << 6) | (this_ch); |
| 219 | leftbits += 6; |
| 220 | if ( leftbits >= 8 ) { |
| 221 | leftbits -= 8; |
| 222 | *bin_data++ = (leftchar >> leftbits) & 0xff; |
| 223 | leftchar &= ((1 << leftbits) - 1); |
| 224 | bin_len--; |
| 225 | } |
| 226 | } |
| 227 | /* |
| 228 | ** Finally, check that if there's anything left on the line |
| 229 | ** that it's whitespace only. |
| 230 | */ |
| 231 | while( ascii_len-- > 0 ) { |
| 232 | this_ch = *ascii_data++; |
| 233 | if ( this_ch != ' ' && this_ch != '\n' && this_ch != '\r' ) { |
| 234 | PyErr_SetString(Error, "Trailing garbage"); |
| 235 | Py_DECREF(rv); |
| 236 | return NULL; |
| 237 | } |
| 238 | } |
| 239 | return rv; |
| 240 | } |
| 241 | |
| 242 | static char doc_b2a_uu[] = "(bin) -> ascii. Uuencode line of data"; |
| 243 | |
| 244 | static PyObject * |
| 245 | binascii_b2a_uu(self, args) |
| 246 | PyObject *self; |
| 247 | PyObject *args; |
| 248 | { |
| 249 | unsigned char *ascii_data, *bin_data; |
| 250 | int leftbits = 0; |
| 251 | unsigned char this_ch; |
| 252 | unsigned int leftchar = 0; |
| 253 | PyObject *rv; |
| 254 | int bin_len; |
| 255 | |
| 256 | if ( !PyArg_ParseTuple(args, "s#", &bin_data, &bin_len) ) |
| 257 | return NULL; |
| 258 | if ( bin_len > 45 ) { |
| 259 | /* The 45 is a limit that appears in all uuencode's */ |
| 260 | PyErr_SetString(Error, "At most 45 bytes at once"); |
| 261 | return NULL; |
| 262 | } |
| 263 | |
| 264 | /* We're lazy and allocate to much (fixed up later) */ |
| 265 | if ( (rv=PyString_FromStringAndSize(NULL, bin_len*2)) == NULL ) |
| 266 | return NULL; |
| 267 | ascii_data = (unsigned char *)PyString_AsString(rv); |
| 268 | |
| 269 | /* Store the length */ |
| 270 | *ascii_data++ = ' ' + (bin_len & 077); |
| 271 | |
| 272 | for( ; bin_len > 0 || leftbits != 0 ; bin_len--, bin_data++ ) { |
| 273 | /* Shift the data (or padding) into our buffer */ |
| 274 | if ( bin_len > 0 ) /* Data */ |
| 275 | leftchar = (leftchar << 8) | *bin_data; |
| 276 | else /* Padding */ |
| 277 | leftchar <<= 8; |
| 278 | leftbits += 8; |
| 279 | |
| 280 | /* See if there are 6-bit groups ready */ |
| 281 | while ( leftbits >= 6 ) { |
| 282 | this_ch = (leftchar >> (leftbits-6)) & 0x3f; |
| 283 | leftbits -= 6; |
| 284 | *ascii_data++ = this_ch + ' '; |
| 285 | } |
| 286 | } |
| 287 | *ascii_data++ = '\n'; /* Append a courtesy newline */ |
| 288 | |
| 289 | _PyString_Resize(&rv, (ascii_data - (unsigned char *)PyString_AsString(rv))); |
| 290 | return rv; |
| 291 | } |
| 292 | |
| 293 | static char doc_a2b_hqx[] = "ascii -> bin, done. Decode .hqx coding"; |
| 294 | |
| 295 | static PyObject * |
| 296 | binascii_a2b_hqx(self, args) |
| 297 | PyObject *self; |
| 298 | PyObject *args; |
| 299 | { |
| 300 | unsigned char *ascii_data, *bin_data; |
| 301 | int leftbits = 0; |
| 302 | unsigned char this_ch; |
Jack Jansen | eaeb1c8 | 1995-08-14 12:17:57 +0000 | [diff] [blame] | 303 | unsigned int leftchar = 0; |
Jack Jansen | 7278119 | 1995-08-07 14:34:15 +0000 | [diff] [blame] | 304 | PyObject *rv; |
| 305 | int len; |
| 306 | int done = 0; |
| 307 | |
| 308 | if ( !PyArg_ParseTuple(args, "s#", &ascii_data, &len) ) |
| 309 | return NULL; |
| 310 | |
| 311 | /* Allocate a string that is too big (fixed later) */ |
| 312 | if ( (rv=PyString_FromStringAndSize(NULL, len)) == NULL ) |
| 313 | return NULL; |
| 314 | bin_data = (unsigned char *)PyString_AsString(rv); |
| 315 | |
| 316 | for( ; len > 0 ; len--, ascii_data++ ) { |
| 317 | /* Get the byte and look it up */ |
| 318 | this_ch = table_a2b_hqx[*ascii_data]; |
| 319 | if ( this_ch == SKIP ) |
| 320 | continue; |
| 321 | if ( this_ch == FAIL ) { |
| 322 | PyErr_SetString(Error, "Illegal char"); |
| 323 | Py_DECREF(rv); |
| 324 | return NULL; |
| 325 | } |
| 326 | if ( this_ch == DONE ) { |
| 327 | /* The terminating colon */ |
| 328 | done = 1; |
| 329 | break; |
| 330 | } |
| 331 | |
| 332 | /* Shift it into the buffer and see if any bytes are ready */ |
| 333 | leftchar = (leftchar << 6) | (this_ch); |
| 334 | leftbits += 6; |
| 335 | if ( leftbits >= 8 ) { |
| 336 | leftbits -= 8; |
| 337 | *bin_data++ = (leftchar >> leftbits) & 0xff; |
| 338 | leftchar &= ((1 << leftbits) - 1); |
| 339 | } |
| 340 | } |
| 341 | |
| 342 | if ( leftbits && !done ) { |
| 343 | PyErr_SetString(Incomplete, |
| 344 | "String has incomplete number of bytes"); |
| 345 | Py_DECREF(rv); |
| 346 | return NULL; |
| 347 | } |
| 348 | _PyString_Resize(&rv, (bin_data - (unsigned char *)PyString_AsString(rv))); |
| 349 | if ( rv ) |
| 350 | return Py_BuildValue("Oi", rv, done); |
| 351 | return NULL; |
| 352 | } |
| 353 | |
| 354 | static char doc_rlecode_hqx[] = "Binhex RLE-code binary data"; |
| 355 | |
| 356 | static PyObject * |
| 357 | binascii_rlecode_hqx(self, args) |
| 358 | PyObject *self; |
| 359 | PyObject *args; |
| 360 | { |
| 361 | unsigned char *in_data, *out_data; |
| 362 | PyObject *rv; |
| 363 | unsigned char ch; |
| 364 | int in, inend, len; |
| 365 | |
| 366 | if ( !PyArg_ParseTuple(args, "s#", &in_data, &len) ) |
| 367 | return NULL; |
| 368 | |
| 369 | /* Worst case: output is twice as big as input (fixed later) */ |
| 370 | if ( (rv=PyString_FromStringAndSize(NULL, len*2)) == NULL ) |
| 371 | return NULL; |
| 372 | out_data = (unsigned char *)PyString_AsString(rv); |
| 373 | |
| 374 | for( in=0; in<len; in++) { |
| 375 | ch = in_data[in]; |
| 376 | if ( ch == RUNCHAR ) { |
| 377 | /* RUNCHAR. Escape it. */ |
| 378 | *out_data++ = RUNCHAR; |
| 379 | *out_data++ = 0; |
| 380 | } else { |
| 381 | /* Check how many following are the same */ |
| 382 | for(inend=in+1; |
| 383 | inend<len && in_data[inend] == ch && |
| 384 | inend < in+255; |
| 385 | inend++) ; |
Jack Jansen | 0223aa1 | 1995-08-31 13:44:23 +0000 | [diff] [blame] | 386 | if ( inend - in > 3 ) { |
| 387 | /* More than 3 in a row. Output RLE. */ |
Jack Jansen | 7278119 | 1995-08-07 14:34:15 +0000 | [diff] [blame] | 388 | *out_data++ = ch; |
| 389 | *out_data++ = RUNCHAR; |
| 390 | *out_data++ = inend-in; |
| 391 | in = inend-1; |
| 392 | } else { |
| 393 | /* Less than 3. Output the byte itself */ |
| 394 | *out_data++ = ch; |
| 395 | } |
| 396 | } |
| 397 | } |
| 398 | _PyString_Resize(&rv, (out_data - (unsigned char *)PyString_AsString(rv))); |
| 399 | return rv; |
| 400 | } |
| 401 | |
| 402 | static char doc_b2a_hqx[] = "Encode .hqx data"; |
| 403 | |
| 404 | static PyObject * |
| 405 | binascii_b2a_hqx(self, args) |
| 406 | PyObject *self; |
| 407 | PyObject *args; |
| 408 | { |
| 409 | unsigned char *ascii_data, *bin_data; |
| 410 | int leftbits = 0; |
| 411 | unsigned char this_ch; |
Jack Jansen | eaeb1c8 | 1995-08-14 12:17:57 +0000 | [diff] [blame] | 412 | unsigned int leftchar = 0; |
Jack Jansen | 7278119 | 1995-08-07 14:34:15 +0000 | [diff] [blame] | 413 | PyObject *rv; |
| 414 | int len; |
| 415 | |
| 416 | if ( !PyArg_ParseTuple(args, "s#", &bin_data, &len) ) |
| 417 | return NULL; |
| 418 | |
| 419 | /* Allocate a buffer that is at least large enough */ |
| 420 | if ( (rv=PyString_FromStringAndSize(NULL, len*2)) == NULL ) |
| 421 | return NULL; |
| 422 | ascii_data = (unsigned char *)PyString_AsString(rv); |
| 423 | |
| 424 | for( ; len > 0 ; len--, bin_data++ ) { |
| 425 | /* Shift into our buffer, and output any 6bits ready */ |
| 426 | leftchar = (leftchar << 8) | *bin_data; |
| 427 | leftbits += 8; |
| 428 | while ( leftbits >= 6 ) { |
| 429 | this_ch = (leftchar >> (leftbits-6)) & 0x3f; |
| 430 | leftbits -= 6; |
| 431 | *ascii_data++ = table_b2a_hqx[this_ch]; |
| 432 | } |
| 433 | } |
| 434 | /* Output a possible runt byte */ |
| 435 | if ( leftbits ) { |
| 436 | leftchar <<= (6-leftbits); |
| 437 | *ascii_data++ = table_b2a_hqx[leftchar & 0x3f]; |
| 438 | } |
| 439 | _PyString_Resize(&rv, (ascii_data - (unsigned char *)PyString_AsString(rv))); |
| 440 | return rv; |
| 441 | } |
| 442 | |
| 443 | static char doc_rledecode_hqx[] = "Decode hexbin RLE-coded string"; |
| 444 | |
| 445 | static PyObject * |
| 446 | binascii_rledecode_hqx(self, args) |
| 447 | PyObject *self; |
| 448 | PyObject *args; |
| 449 | { |
| 450 | unsigned char *in_data, *out_data; |
| 451 | unsigned char in_byte, in_repeat; |
| 452 | PyObject *rv; |
| 453 | int in_len, out_len, out_len_left; |
| 454 | |
| 455 | if ( !PyArg_ParseTuple(args, "s#", &in_data, &in_len) ) |
| 456 | return NULL; |
| 457 | |
| 458 | /* Empty string is a special case */ |
| 459 | if ( in_len == 0 ) |
| 460 | return Py_BuildValue("s", ""); |
| 461 | |
| 462 | /* Allocate a buffer of reasonable size. Resized when needed */ |
| 463 | out_len = in_len*2; |
| 464 | if ( (rv=PyString_FromStringAndSize(NULL, out_len)) == NULL ) |
| 465 | return NULL; |
| 466 | out_len_left = out_len; |
| 467 | out_data = (unsigned char *)PyString_AsString(rv); |
| 468 | |
| 469 | /* |
| 470 | ** We need two macros here to get/put bytes and handle |
| 471 | ** end-of-buffer for input and output strings. |
| 472 | */ |
| 473 | #define INBYTE(b) \ |
| 474 | do { \ |
| 475 | if ( --in_len < 0 ) { \ |
| 476 | PyErr_SetString(Incomplete, ""); \ |
| 477 | Py_DECREF(rv); \ |
| 478 | return NULL; \ |
| 479 | } \ |
| 480 | b = *in_data++; \ |
| 481 | } while(0) |
| 482 | |
| 483 | #define OUTBYTE(b) \ |
| 484 | do { \ |
| 485 | if ( --out_len_left < 0 ) { \ |
| 486 | _PyString_Resize(&rv, 2*out_len); \ |
| 487 | if ( rv == NULL ) return NULL; \ |
| 488 | out_data = (unsigned char *)PyString_AsString(rv) + out_len; \ |
| 489 | out_len_left = out_len; \ |
| 490 | out_len = out_len * 2; \ |
| 491 | } \ |
| 492 | *out_data++ = b; \ |
| 493 | } while(0) |
| 494 | |
| 495 | /* |
| 496 | ** Handle first byte separately (since we have to get angry |
| 497 | ** in case of an orphaned RLE code). |
| 498 | */ |
| 499 | INBYTE(in_byte); |
| 500 | |
| 501 | if (in_byte == RUNCHAR) { |
| 502 | INBYTE(in_repeat); |
| 503 | if (in_repeat != 0) { |
| 504 | /* Note Error, not Incomplete (which is at the end |
| 505 | ** of the string only). This is a programmer error. |
| 506 | */ |
| 507 | PyErr_SetString(Error, "Orphaned RLE code at start"); |
| 508 | Py_DECREF(rv); |
| 509 | return NULL; |
| 510 | } |
| 511 | OUTBYTE(RUNCHAR); |
| 512 | } else { |
| 513 | OUTBYTE(in_byte); |
| 514 | } |
| 515 | |
| 516 | while( in_len > 0 ) { |
| 517 | INBYTE(in_byte); |
| 518 | |
| 519 | if (in_byte == RUNCHAR) { |
| 520 | INBYTE(in_repeat); |
| 521 | if ( in_repeat == 0 ) { |
| 522 | /* Just an escaped RUNCHAR value */ |
| 523 | OUTBYTE(RUNCHAR); |
| 524 | } else { |
| 525 | /* Pick up value and output a sequence of it */ |
| 526 | in_byte = out_data[-1]; |
| 527 | while ( --in_repeat > 0 ) |
| 528 | OUTBYTE(in_byte); |
| 529 | } |
| 530 | } else { |
| 531 | /* Normal byte */ |
| 532 | OUTBYTE(in_byte); |
| 533 | } |
| 534 | } |
| 535 | _PyString_Resize(&rv, (out_data - (unsigned char *)PyString_AsString(rv))); |
| 536 | return rv; |
| 537 | } |
| 538 | |
| 539 | static char doc_crc_hqx[] = "(data, oldcrc) -> newcrc. Compute hqx CRC incrementally"; |
| 540 | |
| 541 | static PyObject * |
| 542 | binascii_crc_hqx(self, args) |
| 543 | PyObject *self; |
| 544 | PyObject *args; |
| 545 | { |
| 546 | unsigned char *bin_data; |
| 547 | unsigned int crc; |
| 548 | int len; |
| 549 | |
| 550 | if ( !PyArg_ParseTuple(args, "s#i", &bin_data, &len, &crc) ) |
| 551 | return NULL; |
| 552 | |
| 553 | while(len--) { |
| 554 | crc=((crc<<8)&0xff00)^crctab_hqx[((crc>>8)&0xff)^*bin_data++]; |
| 555 | } |
| 556 | |
| 557 | return Py_BuildValue("i", crc); |
| 558 | } |
| 559 | |
| 560 | /* List of functions defined in the module */ |
| 561 | |
| 562 | static struct PyMethodDef binascii_module_methods[] = { |
| 563 | {"a2b_uu", binascii_a2b_uu, 1, doc_a2b_uu}, |
| 564 | {"b2a_uu", binascii_b2a_uu, 1, doc_b2a_uu}, |
| 565 | {"a2b_hqx", binascii_a2b_hqx, 1, doc_a2b_hqx}, |
| 566 | {"b2a_hqx", binascii_b2a_hqx, 1, doc_b2a_hqx}, |
| 567 | {"rlecode_hqx", binascii_rlecode_hqx, 1, |
| 568 | doc_rlecode_hqx}, |
| 569 | {"rledecode_hqx", binascii_rledecode_hqx, 1, |
| 570 | doc_rledecode_hqx}, |
| 571 | {"crc_hqx", binascii_crc_hqx, 1, doc_crc_hqx}, |
| 572 | {NULL, NULL} /* sentinel */ |
| 573 | }; |
| 574 | |
| 575 | |
| 576 | /* Initialization function for the module (*must* be called initbinascii) */ |
| 577 | static char doc_binascii[] = "Conversion between binary data and ASCII"; |
| 578 | |
| 579 | void |
| 580 | initbinascii() |
| 581 | { |
| 582 | PyObject *m, *d, *x; |
| 583 | |
| 584 | /* Create the module and add the functions */ |
| 585 | m = Py_InitModule("binascii", binascii_module_methods); |
| 586 | |
| 587 | d = PyModule_GetDict(m); |
| 588 | x = PyString_FromString(doc_binascii); |
| 589 | PyDict_SetItemString(d, "__doc__", x); |
| 590 | |
| 591 | Error = PyString_FromString("binascii.Error"); |
| 592 | PyDict_SetItemString(d, "Error", Error); |
| 593 | Incomplete = PyString_FromString("binascii.Incomplete"); |
| 594 | PyDict_SetItemString(d, "Incomplete", Incomplete); |
| 595 | |
| 596 | /* Check for errors */ |
| 597 | if (PyErr_Occurred()) |
| 598 | Py_FatalError("can't initialize module binascii"); |
| 599 | } |