| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * $Id: sym.c,v 1.2 1997/08/04 10:24:25 mdw Exp $ |
| 4 | * |
| 5 | * Symbol table management |
| 6 | * |
| 7 | * (c) 1996 Straylight |
| 8 | */ |
| 9 | |
| 10 | /*----- Licensing notice --------------------------------------------------* |
| 11 | * |
| 12 | * This file is part of `become' |
| 13 | * |
| 14 | * `Become' is free software; you can redistribute it and/or modify |
| 15 | * it under the terms of the GNU General Public License as published by |
| 16 | * the Free Software Foundation; either version 2 of the License, or |
| 17 | * (at your option) any later version. |
| 18 | * |
| 19 | * `Become' is distributed in the hope that it will be useful, |
| 20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 22 | * GNU General Public License for more details. |
| 23 | * |
| 24 | * You should have received a copy of the GNU General Public License |
| 25 | * along with `become'; if not, write to the Free Software Foundation, |
| 26 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 27 | */ |
| 28 | |
| 29 | /*----- Revision history --------------------------------------------------* |
| 30 | * |
| 31 | * $Log: sym.c,v $ |
| 32 | * Revision 1.2 1997/08/04 10:24:25 mdw |
| 33 | * Sources placed under CVS control. |
| 34 | * |
| 35 | * Revision 1.1 1997/07/21 13:47:44 mdw |
| 36 | * Initial revision |
| 37 | * |
| 38 | */ |
| 39 | |
| 40 | /*----- Header files ------------------------------------------------------*/ |
| 41 | |
| 42 | /* --- ANSI headers --- */ |
| 43 | |
| 44 | #include <stdio.h> |
| 45 | #include <stdlib.h> |
| 46 | #include <string.h> |
| 47 | |
| 48 | /* --- Local headers --- */ |
| 49 | |
| 50 | #include "sym.h" |
| 51 | #include "utils.h" |
| 52 | |
| 53 | /*----- Tuning parameters -------------------------------------------------*/ |
| 54 | |
| 55 | /* --- Initial hash table size --- * |
| 56 | * |
| 57 | * This is the initial @mask@ value. It must be of the form %$2^n - 1$%, |
| 58 | * so that it can be used to mask of the bottom bits of a hash value. |
| 59 | */ |
| 60 | |
| 61 | #define sym__iSize 255 /* Size of a new hash table */ |
| 62 | |
| 63 | /* --- Maximum load factor --- * |
| 64 | * |
| 65 | * This parameter controls how much the table has to be loaded before the |
| 66 | * table is extended. The number of elements %$n$%, the number of bins %$b$% |
| 67 | * and the limit %$l$% satisfy the relation %$n < bl$%; if a new item is |
| 68 | * added to the table and this relation is found to be false, the table is |
| 69 | * doubled in size. |
| 70 | * |
| 71 | * The parameter @sym__limFactor@ is the value of %$l$% multiplied by 256; |
| 72 | * fixed point arithmetic is used to calculate the allowable load. Note |
| 73 | * that the exact calculation of this criterion isn't important; what's more |
| 74 | * significant is that the parameter allows tuning of the rehashing process. |
| 75 | * |
| 76 | * The current value is %$3 \over 4$%, which appears to be reasonable on the |
| 77 | * face of things. |
| 78 | */ |
| 79 | |
| 80 | #define sym__limFactor 0x0C0 /* Load factor for growing table */ |
| 81 | |
| 82 | /*----- CRC table ---------------------------------------------------------*/ |
| 83 | |
| 84 | /*****************************************************************/ |
| 85 | /* */ |
| 86 | /* CRC LOOKUP TABLE */ |
| 87 | /* ================ */ |
| 88 | /* */ |
| 89 | /* The following CRC lookup table was generated automagically */ |
| 90 | /* by `crcgen', which is based on the Rocksoft^tm Model CRC */ |
| 91 | /* Algorithm Table Generation Program. The model parameters */ |
| 92 | /* supplied to `crcgen' were: */ |
| 93 | /* */ |
| 94 | /* Width : 32 bits */ |
| 95 | /* Poly : 0x04C11DB7 */ |
| 96 | /* Init : 0xFFFFFFFF */ |
| 97 | /* XorOut : 0xFFFFFFFF */ |
| 98 | /* Reverse : Yes */ |
| 99 | /* Check : 0xCBF43926 */ |
| 100 | /* */ |
| 101 | /* For more information on the Rocksoft^tm Model CRC Algorithm, */ |
| 102 | /* see the document titled `A Painless Guide to CRC Error */ |
| 103 | /* Detection Algorithms' by Ross Williams */ |
| 104 | /* (ross@@guest.adelaide.edu.au.). This document is likely to be */ |
| 105 | /* in the FTP archive `ftp.adelaide.edu.au/pub/rocksoft'. */ |
| 106 | /* */ |
| 107 | /*****************************************************************/ |
| 108 | |
| 109 | static unsigned long sym__crcTable[256] = { |
| 110 | 0x00000000L, 0x77073096L, 0xEE0E612CL, 0x990951BAL, |
| 111 | 0x076DC419L, 0x706AF48FL, 0xE963A535L, 0x9E6495A3L, |
| 112 | 0x0EDB8832L, 0x79DCB8A4L, 0xE0D5E91EL, 0x97D2D988L, |
| 113 | 0x09B64C2BL, 0x7EB17CBDL, 0xE7B82D07L, 0x90BF1D91L, |
| 114 | 0x1DB71064L, 0x6AB020F2L, 0xF3B97148L, 0x84BE41DEL, |
| 115 | 0x1ADAD47DL, 0x6DDDE4EBL, 0xF4D4B551L, 0x83D385C7L, |
| 116 | 0x136C9856L, 0x646BA8C0L, 0xFD62F97AL, 0x8A65C9ECL, |
| 117 | 0x14015C4FL, 0x63066CD9L, 0xFA0F3D63L, 0x8D080DF5L, |
| 118 | 0x3B6E20C8L, 0x4C69105EL, 0xD56041E4L, 0xA2677172L, |
| 119 | 0x3C03E4D1L, 0x4B04D447L, 0xD20D85FDL, 0xA50AB56BL, |
| 120 | 0x35B5A8FAL, 0x42B2986CL, 0xDBBBC9D6L, 0xACBCF940L, |
| 121 | 0x32D86CE3L, 0x45DF5C75L, 0xDCD60DCFL, 0xABD13D59L, |
| 122 | 0x26D930ACL, 0x51DE003AL, 0xC8D75180L, 0xBFD06116L, |
| 123 | 0x21B4F4B5L, 0x56B3C423L, 0xCFBA9599L, 0xB8BDA50FL, |
| 124 | 0x2802B89EL, 0x5F058808L, 0xC60CD9B2L, 0xB10BE924L, |
| 125 | 0x2F6F7C87L, 0x58684C11L, 0xC1611DABL, 0xB6662D3DL, |
| 126 | 0x76DC4190L, 0x01DB7106L, 0x98D220BCL, 0xEFD5102AL, |
| 127 | 0x71B18589L, 0x06B6B51FL, 0x9FBFE4A5L, 0xE8B8D433L, |
| 128 | 0x7807C9A2L, 0x0F00F934L, 0x9609A88EL, 0xE10E9818L, |
| 129 | 0x7F6A0DBBL, 0x086D3D2DL, 0x91646C97L, 0xE6635C01L, |
| 130 | 0x6B6B51F4L, 0x1C6C6162L, 0x856530D8L, 0xF262004EL, |
| 131 | 0x6C0695EDL, 0x1B01A57BL, 0x8208F4C1L, 0xF50FC457L, |
| 132 | 0x65B0D9C6L, 0x12B7E950L, 0x8BBEB8EAL, 0xFCB9887CL, |
| 133 | 0x62DD1DDFL, 0x15DA2D49L, 0x8CD37CF3L, 0xFBD44C65L, |
| 134 | 0x4DB26158L, 0x3AB551CEL, 0xA3BC0074L, 0xD4BB30E2L, |
| 135 | 0x4ADFA541L, 0x3DD895D7L, 0xA4D1C46DL, 0xD3D6F4FBL, |
| 136 | 0x4369E96AL, 0x346ED9FCL, 0xAD678846L, 0xDA60B8D0L, |
| 137 | 0x44042D73L, 0x33031DE5L, 0xAA0A4C5FL, 0xDD0D7CC9L, |
| 138 | 0x5005713CL, 0x270241AAL, 0xBE0B1010L, 0xC90C2086L, |
| 139 | 0x5768B525L, 0x206F85B3L, 0xB966D409L, 0xCE61E49FL, |
| 140 | 0x5EDEF90EL, 0x29D9C998L, 0xB0D09822L, 0xC7D7A8B4L, |
| 141 | 0x59B33D17L, 0x2EB40D81L, 0xB7BD5C3BL, 0xC0BA6CADL, |
| 142 | 0xEDB88320L, 0x9ABFB3B6L, 0x03B6E20CL, 0x74B1D29AL, |
| 143 | 0xEAD54739L, 0x9DD277AFL, 0x04DB2615L, 0x73DC1683L, |
| 144 | 0xE3630B12L, 0x94643B84L, 0x0D6D6A3EL, 0x7A6A5AA8L, |
| 145 | 0xE40ECF0BL, 0x9309FF9DL, 0x0A00AE27L, 0x7D079EB1L, |
| 146 | 0xF00F9344L, 0x8708A3D2L, 0x1E01F268L, 0x6906C2FEL, |
| 147 | 0xF762575DL, 0x806567CBL, 0x196C3671L, 0x6E6B06E7L, |
| 148 | 0xFED41B76L, 0x89D32BE0L, 0x10DA7A5AL, 0x67DD4ACCL, |
| 149 | 0xF9B9DF6FL, 0x8EBEEFF9L, 0x17B7BE43L, 0x60B08ED5L, |
| 150 | 0xD6D6A3E8L, 0xA1D1937EL, 0x38D8C2C4L, 0x4FDFF252L, |
| 151 | 0xD1BB67F1L, 0xA6BC5767L, 0x3FB506DDL, 0x48B2364BL, |
| 152 | 0xD80D2BDAL, 0xAF0A1B4CL, 0x36034AF6L, 0x41047A60L, |
| 153 | 0xDF60EFC3L, 0xA867DF55L, 0x316E8EEFL, 0x4669BE79L, |
| 154 | 0xCB61B38CL, 0xBC66831AL, 0x256FD2A0L, 0x5268E236L, |
| 155 | 0xCC0C7795L, 0xBB0B4703L, 0x220216B9L, 0x5505262FL, |
| 156 | 0xC5BA3BBEL, 0xB2BD0B28L, 0x2BB45A92L, 0x5CB36A04L, |
| 157 | 0xC2D7FFA7L, 0xB5D0CF31L, 0x2CD99E8BL, 0x5BDEAE1DL, |
| 158 | 0x9B64C2B0L, 0xEC63F226L, 0x756AA39CL, 0x026D930AL, |
| 159 | 0x9C0906A9L, 0xEB0E363FL, 0x72076785L, 0x05005713L, |
| 160 | 0x95BF4A82L, 0xE2B87A14L, 0x7BB12BAEL, 0x0CB61B38L, |
| 161 | 0x92D28E9BL, 0xE5D5BE0DL, 0x7CDCEFB7L, 0x0BDBDF21L, |
| 162 | 0x86D3D2D4L, 0xF1D4E242L, 0x68DDB3F8L, 0x1FDA836EL, |
| 163 | 0x81BE16CDL, 0xF6B9265BL, 0x6FB077E1L, 0x18B74777L, |
| 164 | 0x88085AE6L, 0xFF0F6A70L, 0x66063BCAL, 0x11010B5CL, |
| 165 | 0x8F659EFFL, 0xF862AE69L, 0x616BFFD3L, 0x166CCF45L, |
| 166 | 0xA00AE278L, 0xD70DD2EEL, 0x4E048354L, 0x3903B3C2L, |
| 167 | 0xA7672661L, 0xD06016F7L, 0x4969474DL, 0x3E6E77DBL, |
| 168 | 0xAED16A4AL, 0xD9D65ADCL, 0x40DF0B66L, 0x37D83BF0L, |
| 169 | 0xA9BCAE53L, 0xDEBB9EC5L, 0x47B2CF7FL, 0x30B5FFE9L, |
| 170 | 0xBDBDF21CL, 0xCABAC28AL, 0x53B39330L, 0x24B4A3A6L, |
| 171 | 0xBAD03605L, 0xCDD70693L, 0x54DE5729L, 0x23D967BFL, |
| 172 | 0xB3667A2EL, 0xC4614AB8L, 0x5D681B02L, 0x2A6F2B94L, |
| 173 | 0xB40BBE37L, 0xC30C8EA1L, 0x5A05DF1BL, 0x2D02EF8DL, |
| 174 | }; |
| 175 | |
| 176 | /*****************************************************************/ |
| 177 | /* End of CRC Lookup Table */ |
| 178 | /*****************************************************************/ |
| 179 | |
| 180 | /* --- Work out the CRC of a bytestring --- */ |
| 181 | |
| 182 | #define sym__crc(s_, l_, hv_) do { \ |
| 183 | unsigned long h_ = 0xFFFFFFFFL; \ |
| 184 | const char *p_ = s_; \ |
| 185 | const char *e_ = (s_) + (l_); \ |
| 186 | \ |
| 187 | while (p_ < e_) \ |
| 188 | h_ = (h_ >> 8) ^ (sym__crcTable[(*p_++ ^ h_) & 0xFF]); \ |
| 189 | hv_ = ~h_ & 0xFFFFFFFFL; \ |
| 190 | } while (0) |
| 191 | |
| 192 | /*----- Main code ---------------------------------------------------------*/ |
| 193 | |
| 194 | #ifndef DEBUG_CRC |
| 195 | |
| 196 | /* --- @sym_createTable@ --- * |
| 197 | * |
| 198 | * Arguments: @sym_table *t@ = symbol table to initialise |
| 199 | * |
| 200 | * Returns: --- |
| 201 | * |
| 202 | * Use: Initialises the given symbol table. |
| 203 | */ |
| 204 | |
| 205 | void sym_createTable(sym_table *t) |
| 206 | { |
| 207 | size_t i; |
| 208 | |
| 209 | t->mask = sym__iSize; |
| 210 | t->c = (sym__iSize * sym__limFactor) >> 8; |
| 211 | t->a = xmalloc((t->mask + 1) * sizeof(sym_base *)); |
| 212 | |
| 213 | for (i = 0; i < sym__iSize + 1; i++) |
| 214 | t->a[i] = 0; |
| 215 | } |
| 216 | |
| 217 | /* --- @sym_destroyTable@ --- * |
| 218 | * |
| 219 | * Arguments: @sym_table *t@ = pointer to symbol table in question |
| 220 | * |
| 221 | * Returns: --- |
| 222 | * |
| 223 | * Use: Destroys a symbol table, freeing all the memory it used to |
| 224 | * occupy. |
| 225 | */ |
| 226 | |
| 227 | void sym_destroyTable(sym_table *t) |
| 228 | { |
| 229 | size_t i; |
| 230 | sym_base *p, *q; |
| 231 | |
| 232 | for (i = 0; i <= t->mask; i++) { |
| 233 | p = t->a[i]; |
| 234 | while (p) { |
| 235 | q = p->next; |
| 236 | free(p); |
| 237 | p = q; |
| 238 | } |
| 239 | } |
| 240 | } |
| 241 | |
| 242 | /* --- @sym_find@ --- * |
| 243 | * |
| 244 | * Arguments: @sym_table *t@ = pointer to symbol table in question |
| 245 | * @const char *n@ = pointer to symbol table to look up |
| 246 | * @long l@ = length of the name string or negative to measure |
| 247 | * @size_t sz@ = size of desired symbol object, or zero |
| 248 | * @unsigned *f@ = pointer to a flag, or null. |
| 249 | * |
| 250 | * Returns: The address of a @sym_base@ structure, or null if not found |
| 251 | * and @sz@ is zero. |
| 252 | * |
| 253 | * Use: Looks up a symbol in a given symbol table. The name is |
| 254 | * passed by the address of its first character. The length |
| 255 | * may be given, in which case the name may contain arbitrary |
| 256 | * binary data, or it may be given as a negative number, in |
| 257 | * which case the length of the name is calculated as |
| 258 | * @strlen(n)@. |
| 259 | * |
| 260 | * The return value is the address of a pointer to a @sym_base@ |
| 261 | * block (which may have other things on the end, as above). If |
| 262 | * the symbol could be found, the return value points to the |
| 263 | * symbol block. If the symbol wasn't there, then if @sz@ is |
| 264 | * nonzero, a new symbol is created and its address is returned; |
| 265 | * otherwise a null pointer is returned. |
| 266 | * |
| 267 | * The value of @*f@ indicates whether a new symbol entry was |
| 268 | * created: a nonzero value indicates that an old value was |
| 269 | * found. |
| 270 | */ |
| 271 | |
| 272 | void *sym_find(sym_table *t, const char *n, long l, size_t sz, unsigned *f) |
| 273 | { |
| 274 | unsigned long hash; /* Hash value for user's name */ |
| 275 | size_t len = l < 0 ? strlen(n) + 1 : l; /* Find length of user's name */ |
| 276 | sym_base *bin; /* Bin containing our item */ |
| 277 | sym_base *p, *q; /* Pointer wandering through list */ |
| 278 | |
| 279 | /* --- Find the correct bin --- */ |
| 280 | |
| 281 | sym__crc(n, len, hash); /* Find hash value for this name */ |
| 282 | bin = p = (sym_base *)(t->a + (hash & t->mask)); |
| 283 | |
| 284 | /* --- Search the bin list --- */ |
| 285 | |
| 286 | while (p->next) { |
| 287 | if (hash == p->next->hash && /* Check hash values first */ |
| 288 | len == p->next->len && /* Then compare string lengths */ |
| 289 | !memcmp(n, p->next->name, len)) /* And finally compare the strings */ |
| 290 | { |
| 291 | /* --- Found a match --- * |
| 292 | * |
| 293 | * As a minor, and probably pointless, tweak, move the item to the |
| 294 | * front of its bin list. |
| 295 | */ |
| 296 | |
| 297 | q = p->next; /* Find the actual symbol block */ |
| 298 | p->next = q->next; /* Extract block from bin list */ |
| 299 | q->next = bin->next; /* Set up symbol's next pointer */ |
| 300 | bin->next = q; /* And reinsert the block */ |
| 301 | |
| 302 | /* --- Return the block --- */ |
| 303 | |
| 304 | if (f) *f = 1; /* Didn't fail to find the item */ |
| 305 | return (q); /* And return the block */ |
| 306 | } |
| 307 | |
| 308 | p = p->next; /* Move onto the next item */ |
| 309 | } |
| 310 | |
| 311 | /* --- Couldn't find the item there --- */ |
| 312 | |
| 313 | if (f) *f = 0; /* Failed to find the block */ |
| 314 | if (!sz) return (0); /* Return zero if not creating */ |
| 315 | |
| 316 | /* --- Create a new symbol block and initialise it --- */ |
| 317 | |
| 318 | p = xmalloc(sz); /* Create a new symbol block */ |
| 319 | p->next = bin->next; /* Set up the next pointer */ |
| 320 | p->hash = hash; /* Set up the hash value too */ |
| 321 | p->name = xmalloc(len); /* Allocate a block for the name */ |
| 322 | p->len = len; /* And set up the string length */ |
| 323 | memcpy(p->name, n, len); /* And copy the string over */ |
| 324 | |
| 325 | bin->next = p; /* Put the pointer into the bin */ |
| 326 | |
| 327 | /* --- Consider growing the array --- */ |
| 328 | |
| 329 | if (!--t->c) { |
| 330 | unsigned long m = t->mask + 1; /* Next set bit in has word */ |
| 331 | sym_base *p, *q, *r; /* More useful pointers */ |
| 332 | size_t i, lim; /* Loop counter and limit */ |
| 333 | |
| 334 | /* --- Update values in the anchor block --- */ |
| 335 | |
| 336 | t->c = ((t->mask + 1) * sym__limFactor) >> 8; /* Set load value */ |
| 337 | t->mask = (t->mask + 1) * 2 - 1; /* Set the new mask value */ |
| 338 | t->a = xrealloc(t->a, (t->mask + 1) * sizeof(sym_base *)); |
| 339 | |
| 340 | /* --- Now wander through the table rehashing things --- * |
| 341 | * |
| 342 | * This loop is very careful to avoid problems with aliasing. The items |
| 343 | * are dealt with from the end backwards to avoid overwriting bins before |
| 344 | * they've been processed. |
| 345 | */ |
| 346 | |
| 347 | lim = (t->mask + 1) >> 1; |
| 348 | for (i = 0; i < lim; i++) { |
| 349 | /* --- Some initialisation --- */ |
| 350 | |
| 351 | r = t->a[i]; /* Find the list we're dissecting */ |
| 352 | p = (sym_base *)(t->a + i); /* Find bit-clear list */ |
| 353 | q = (sym_base *)(t->a + i + lim); /* And the bit-set lsit */ |
| 354 | |
| 355 | /* --- Now go through the @r@ list --- */ |
| 356 | |
| 357 | while (r) { |
| 358 | if (r->hash & m) /* Is the next bit set? */ |
| 359 | q = q->next = r; /* Yes, so fit up previous link */ |
| 360 | else |
| 361 | p = p->next = r; /* No, so fit up previous link */ |
| 362 | r = r->next; /* Move onto the next item */ |
| 363 | } |
| 364 | p->next = q->next = 0; /* Null terminate the new lists */ |
| 365 | } |
| 366 | } |
| 367 | |
| 368 | /* --- Finished that, so return the new symbol block --- */ |
| 369 | |
| 370 | return (p); |
| 371 | } |
| 372 | |
| 373 | /* --- @sym_remove@ --- * |
| 374 | * |
| 375 | * Arguments: @sym_table *i@ = pointer to a symbol table object |
| 376 | * @void *b@ = pointer to symbol table entry |
| 377 | * |
| 378 | * Returns: --- |
| 379 | * |
| 380 | * Use: Removes the object from the symbol table. The space occupied |
| 381 | * by the object and its name is freed; anything else attached |
| 382 | * to the entry should already be gone by this point. |
| 383 | */ |
| 384 | |
| 385 | void sym_remove(sym_table *t, void *b) |
| 386 | { |
| 387 | /* --- A quick comment --- * |
| 388 | * |
| 389 | * Since the @sym_base@ block contains the hash, finding the element in the |
| 390 | * bin list is really quick -- it's not worth bothering with things like |
| 391 | * doubly linked lists. |
| 392 | */ |
| 393 | |
| 394 | sym_base *p = b; |
| 395 | sym_base *bin = (sym_base *)(t->a + (p->hash & t->mask)); |
| 396 | |
| 397 | /* --- Find the item in the bin list --- */ |
| 398 | |
| 399 | while (bin->next) { |
| 400 | if (bin->next == p) |
| 401 | break; |
| 402 | bin = bin->next; |
| 403 | } |
| 404 | if (!bin->next) |
| 405 | return; |
| 406 | |
| 407 | /* --- Now just remove the item from the list and free it --- * |
| 408 | * |
| 409 | * Oh, and bump the load counter. |
| 410 | */ |
| 411 | |
| 412 | bin->next = p->next; |
| 413 | free(p->name); |
| 414 | free(p); |
| 415 | t->c++; |
| 416 | } |
| 417 | |
| 418 | /* --- @sym_createIter@ --- * |
| 419 | * |
| 420 | * Arguments: @sym_iter *i@ = pointer to an iterator object |
| 421 | * @sym_table *t@ = pointer to a symbol table object |
| 422 | * |
| 423 | * Returns: --- |
| 424 | * |
| 425 | * Use: Creates a new symbol table iterator which may be used to |
| 426 | * iterate through a symbol table. |
| 427 | */ |
| 428 | |
| 429 | void sym_createIter(sym_iter *i, sym_table *t) |
| 430 | { |
| 431 | i->t = t; |
| 432 | i->i = 0; |
| 433 | i->n = 0; |
| 434 | } |
| 435 | |
| 436 | /* --- @sym_next@ --- * |
| 437 | * |
| 438 | * Arguments: @sym_iter *i@ = pointer to iterator object |
| 439 | * |
| 440 | * Returns: Pointer to the next symbol found, or null when finished. |
| 441 | * |
| 442 | * Use: Returns the next symbol from the table. Symbols are not |
| 443 | * returned in any particular order. |
| 444 | */ |
| 445 | |
| 446 | void *sym_next(sym_iter *i) |
| 447 | { |
| 448 | sym_base *p; |
| 449 | |
| 450 | /* --- Find the next item --- */ |
| 451 | |
| 452 | while (!i->n) { |
| 453 | if (i->i > i->t->mask) |
| 454 | return (0); |
| 455 | i->n = i->t->a[i->i++]; |
| 456 | } |
| 457 | |
| 458 | /* --- Update the iterator block --- */ |
| 459 | |
| 460 | p = i->n; |
| 461 | i->n = p->next; |
| 462 | |
| 463 | /* --- Done --- */ |
| 464 | |
| 465 | return (p); |
| 466 | } |
| 467 | |
| 468 | #endif |
| 469 | |
| 470 | /*----- CRC test code -----------------------------------------------------*/ |
| 471 | |
| 472 | #ifdef DEBUG_CRC |
| 473 | |
| 474 | int main(void) |
| 475 | { |
| 476 | unsigned long h; |
| 477 | sym__crc("123456789", 9, h); |
| 478 | printf("crc check == %04x\n", h); |
| 479 | return (0); |
| 480 | } |
| 481 | |
| 482 | #endif |
| 483 | |
| 484 | /*----- Symbol table test code --------------------------------------------*/ |
| 485 | |
| 486 | #ifdef TEST_RIG |
| 487 | |
| 488 | #include <errno.h> |
| 489 | #include <time.h> |
| 490 | |
| 491 | #include "dbutils.h" |
| 492 | |
| 493 | typedef struct sym_word { |
| 494 | sym_base base; |
| 495 | size_t i; |
| 496 | } sym_word; |
| 497 | |
| 498 | |
| 499 | /* --- What it does --- * |
| 500 | * |
| 501 | * Reads the file /usr/dict/words (change to some other file full of |
| 502 | * interesting and appropriate bits of text to taste) into a big buffer and |
| 503 | * picks apart into lines. Then picks lines at random and enters them into |
| 504 | * the symbol table. |
| 505 | */ |
| 506 | |
| 507 | int main(void) |
| 508 | { |
| 509 | char *buff, *p, *lim; |
| 510 | size_t sz, done; |
| 511 | FILE *fp; |
| 512 | int i; |
| 513 | char **line; |
| 514 | sym_word **flag; |
| 515 | sym_table tbl; |
| 516 | int entries; |
| 517 | |
| 518 | /* --- Initialise for reading the file --- */ |
| 519 | |
| 520 | sz = BUFSIZ; |
| 521 | buff = xmalloc(sz + 1); |
| 522 | done = 0; |
| 523 | |
| 524 | if ((fp = fopen("/usr/dict/words", "r")) == 0) |
| 525 | fprintf(stderr, "buggered ;-( (%s)\n", strerror(errno)); |
| 526 | |
| 527 | /* --- Read buffers of text --- * |
| 528 | * |
| 529 | * Read a buffer. If more to come, double the buffer size and try again. |
| 530 | * This is the method I recommended to comp.lang.c, so I may as well try |
| 531 | * it. |
| 532 | */ |
| 533 | |
| 534 | for (;;) { |
| 535 | i = fread(buff + done, 1, sz - done, fp); |
| 536 | done += i; |
| 537 | if (done != sz) |
| 538 | break; |
| 539 | sz <<= 1; |
| 540 | buff = xrealloc(buff, sz + 1); |
| 541 | } |
| 542 | |
| 543 | /* --- Count the lines --- */ |
| 544 | |
| 545 | lim = buff + done; |
| 546 | |
| 547 | sz = 1; |
| 548 | for (p = buff; p < lim; p++) |
| 549 | if (*p == '\n') sz++; |
| 550 | |
| 551 | /* --- Build a table of line starts --- */ |
| 552 | |
| 553 | line = xmalloc(sz * sizeof(char *)); |
| 554 | i = 0; |
| 555 | line[i++] = buff; |
| 556 | for (p = buff; p < lim; p++) |
| 557 | if (*p == '\n') *p = 0, line[i++] = p + 1; |
| 558 | *lim = 0; |
| 559 | |
| 560 | /* --- Build a table of lines --- * |
| 561 | * |
| 562 | * This reverses the mapping which the symbol table performs, so that its |
| 563 | * accuracy can be tested. |
| 564 | */ |
| 565 | |
| 566 | flag = xmalloc(sz * sizeof(sym_word *)); |
| 567 | for (i = 0; i < sz; i++) |
| 568 | flag[i] = 0; |
| 569 | entries = 0; |
| 570 | |
| 571 | sym_createTable(&tbl); |
| 572 | |
| 573 | for (;;) { |
| 574 | i = (unsigned)rand() % sz; |
| 575 | |
| 576 | switch (rand() % 5) |
| 577 | { |
| 578 | case 0: { |
| 579 | sym_word *w; |
| 580 | |
| 581 | /* printf("find `%s'\n", line[i]); */ |
| 582 | if ((rand() & 1023) == 0) { |
| 583 | putchar('.'); fflush(stdout); |
| 584 | } |
| 585 | |
| 586 | w = sym_find(&tbl, line[i], -1, 0, 0); |
| 587 | if (w != flag[i]) |
| 588 | printf("*** error: find `%s' gave %p not %p\n", |
| 589 | line[i], (void *)w, (void *)flag[i]); |
| 590 | else if (w && w->i != i) |
| 591 | printf("*** error: find sym for `%s' gives index %i not %i\n", |
| 592 | line[i], w->i, i); |
| 593 | } break; |
| 594 | |
| 595 | case 1: { |
| 596 | unsigned f; |
| 597 | sym_word *w; |
| 598 | |
| 599 | /* printf("create `%s'\n", line[i]); */ |
| 600 | if ((rand() & 1023) == 0) { |
| 601 | putchar('+'); fflush(stdout); |
| 602 | } |
| 603 | |
| 604 | w = sym_find(&tbl, line[i], -1, sizeof(sym_word), &f); |
| 605 | if (f) |
| 606 | { |
| 607 | if (w != flag[i]) |
| 608 | printf("*** error: create `%s' gave %p not %p\n", |
| 609 | line[i], (void *)w, (void *)flag[i]); |
| 610 | else if (w && w->i != i) |
| 611 | printf("*** error: create sym for `%s' gives index %i not %i\n", |
| 612 | line[i], w->i, i); |
| 613 | } |
| 614 | else |
| 615 | { |
| 616 | if (flag[i]) |
| 617 | printf("*** error: create `%s' gave new block, should be %p\n", |
| 618 | line[i], (void *)flag[i]); |
| 619 | else { |
| 620 | flag[i] = w; |
| 621 | w->i = i; |
| 622 | entries++; |
| 623 | } |
| 624 | } |
| 625 | } break; |
| 626 | |
| 627 | case 2: { |
| 628 | sym_iter it; |
| 629 | sym_word *w, **ntbl; |
| 630 | int v = (rand() % entries) == 0; |
| 631 | if (!v) |
| 632 | break; |
| 633 | printf("\niterated %i entries\n", entries); |
| 634 | break; |
| 635 | |
| 636 | printf("iterate\n"); |
| 637 | |
| 638 | ntbl = xmalloc(sz * sizeof(sym_word *)); |
| 639 | memcpy(ntbl, flag, sz * sizeof(sym_word *)); |
| 640 | sym_createIter(&it, &tbl); |
| 641 | |
| 642 | while ((w = sym_next(&it)) != 0) { |
| 643 | if (ntbl[w->i] == 0) |
| 644 | printf("*** error: iterate returned duff item %i\n", w->i); |
| 645 | else |
| 646 | ntbl[w->i] = 0; |
| 647 | } |
| 648 | |
| 649 | for (i = 0; i < sz; i++) |
| 650 | if (ntbl[i]) printf("*** error: iterate didn't return item %i\n", |
| 651 | i); |
| 652 | free(ntbl); |
| 653 | } break; |
| 654 | |
| 655 | case 3: { |
| 656 | sym_base *b; |
| 657 | int v = rand() & 255 ? 0 : 1; |
| 658 | break; |
| 659 | |
| 660 | printf("dump\n"); |
| 661 | |
| 662 | for (i = 0; i <= tbl.mask; i++) { |
| 663 | if (!tbl.a[i]) continue; |
| 664 | if (v) printf(" %i: ", i); |
| 665 | b = tbl.a[i]; |
| 666 | while (b) { |
| 667 | if ((b->hash & tbl.mask) != i) |
| 668 | printf("*** error: bad hash value found"); |
| 669 | if (v) printf("`%s'(%08lx:%lu) ", |
| 670 | line[((sym_word *)b)->i], |
| 671 | b->hash, |
| 672 | b->hash & tbl.mask); |
| 673 | b = b->next; |
| 674 | } |
| 675 | if (v) putchar('\n'); |
| 676 | } |
| 677 | } break; |
| 678 | |
| 679 | case 4: { |
| 680 | if (flag[i]) { |
| 681 | /* printf("remove `%s'\n", flag[i]->base.name); */ |
| 682 | if ((rand() & 1023) == 0) { |
| 683 | putchar('-'); fflush(stdout); |
| 684 | } |
| 685 | sym_remove(&tbl, flag[i]); |
| 686 | flag[i] = 0; |
| 687 | entries--; |
| 688 | } |
| 689 | } break; |
| 690 | } |
| 691 | |
| 692 | } |
| 693 | |
| 694 | return (0); |
| 695 | } |
| 696 | |
| 697 | #endif |
| 698 | |
| 699 | /*----- That's all, folks -------------------------------------------------*/ |