c4f2d992 |
1 | /* -*-c-*- |
2 | * |
3 | * $Id: sym.c,v 1.1 1997/07/21 13:47:44 mdw Exp $ |
4 | * |
5 | * Symbol table management |
6 | * |
7 | * (c) 1996 Straylight |
8 | */ |
9 | |
10 | /*----- Licencing 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 |
26 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
27 | */ |
28 | |
29 | /*----- Revision history --------------------------------------------------* |
30 | * |
31 | * $Log: sym.c,v $ |
32 | * Revision 1.1 1997/07/21 13:47:44 mdw |
33 | * Initial revision |
34 | * |
35 | */ |
36 | |
37 | /*----- Header files ------------------------------------------------------*/ |
38 | |
39 | /* --- ANSI headers --- */ |
40 | |
41 | #include <stdio.h> |
42 | #include <stdlib.h> |
43 | #include <string.h> |
44 | |
45 | /* --- Local headers --- */ |
46 | |
47 | #include "sym.h" |
48 | #include "utils.h" |
49 | |
50 | /*----- Tuning parameters -------------------------------------------------*/ |
51 | |
52 | /* --- Initial hash table size --- * |
53 | * |
54 | * This is the initial @mask@ value. It must be of the form %$2^n - 1$%, |
55 | * so that it can be used to mask of the bottom bits of a hash value. |
56 | */ |
57 | |
58 | #define sym__iSize 255 /* Size of a new hash table */ |
59 | |
60 | /* --- Maximum load factor --- * |
61 | * |
62 | * This parameter controls how much the table has to be loaded before the |
63 | * table is extended. The number of elements %$n$%, the number of bins %$b$% |
64 | * and the limit %$l$% satisfy the relation %$n < bl$%; if a new item is |
65 | * added to the table and this relation is found to be false, the table is |
66 | * doubled in size. |
67 | * |
68 | * The parameter @sym__limFactor@ is the value of %$l$% multiplied by 256; |
69 | * fixed point arithmetic is used to calculate the allowable load. Note |
70 | * that the exact calculation of this criterion isn't important; what's more |
71 | * significant is that the parameter allows tuning of the rehashing process. |
72 | * |
73 | * The current value is %$3 \over 4$%, which appears to be reasonable on the |
74 | * face of things. |
75 | */ |
76 | |
77 | #define sym__limFactor 0x0C0 /* Load factor for growing table */ |
78 | |
79 | /*----- CRC table ---------------------------------------------------------*/ |
80 | |
81 | /*****************************************************************/ |
82 | /* */ |
83 | /* CRC LOOKUP TABLE */ |
84 | /* ================ */ |
85 | /* */ |
86 | /* The following CRC lookup table was generated automagically */ |
87 | /* by `crcgen', which is based on the Rocksoft^tm Model CRC */ |
88 | /* Algorithm Table Generation Program. The model parameters */ |
89 | /* supplied to `crcgen' were: */ |
90 | /* */ |
91 | /* Width : 32 bits */ |
92 | /* Poly : 0x04C11DB7 */ |
93 | /* Init : 0xFFFFFFFF */ |
94 | /* XorOut : 0xFFFFFFFF */ |
95 | /* Reverse : Yes */ |
96 | /* Check : 0xCBF43926 */ |
97 | /* */ |
98 | /* For more information on the Rocksoft^tm Model CRC Algorithm, */ |
99 | /* see the document titled `A Painless Guide to CRC Error */ |
100 | /* Detection Algorithms' by Ross Williams */ |
101 | /* (ross@@guest.adelaide.edu.au.). This document is likely to be */ |
102 | /* in the FTP archive `ftp.adelaide.edu.au/pub/rocksoft'. */ |
103 | /* */ |
104 | /*****************************************************************/ |
105 | |
106 | static unsigned long sym__crcTable[256] = { |
107 | 0x00000000L, 0x77073096L, 0xEE0E612CL, 0x990951BAL, |
108 | 0x076DC419L, 0x706AF48FL, 0xE963A535L, 0x9E6495A3L, |
109 | 0x0EDB8832L, 0x79DCB8A4L, 0xE0D5E91EL, 0x97D2D988L, |
110 | 0x09B64C2BL, 0x7EB17CBDL, 0xE7B82D07L, 0x90BF1D91L, |
111 | 0x1DB71064L, 0x6AB020F2L, 0xF3B97148L, 0x84BE41DEL, |
112 | 0x1ADAD47DL, 0x6DDDE4EBL, 0xF4D4B551L, 0x83D385C7L, |
113 | 0x136C9856L, 0x646BA8C0L, 0xFD62F97AL, 0x8A65C9ECL, |
114 | 0x14015C4FL, 0x63066CD9L, 0xFA0F3D63L, 0x8D080DF5L, |
115 | 0x3B6E20C8L, 0x4C69105EL, 0xD56041E4L, 0xA2677172L, |
116 | 0x3C03E4D1L, 0x4B04D447L, 0xD20D85FDL, 0xA50AB56BL, |
117 | 0x35B5A8FAL, 0x42B2986CL, 0xDBBBC9D6L, 0xACBCF940L, |
118 | 0x32D86CE3L, 0x45DF5C75L, 0xDCD60DCFL, 0xABD13D59L, |
119 | 0x26D930ACL, 0x51DE003AL, 0xC8D75180L, 0xBFD06116L, |
120 | 0x21B4F4B5L, 0x56B3C423L, 0xCFBA9599L, 0xB8BDA50FL, |
121 | 0x2802B89EL, 0x5F058808L, 0xC60CD9B2L, 0xB10BE924L, |
122 | 0x2F6F7C87L, 0x58684C11L, 0xC1611DABL, 0xB6662D3DL, |
123 | 0x76DC4190L, 0x01DB7106L, 0x98D220BCL, 0xEFD5102AL, |
124 | 0x71B18589L, 0x06B6B51FL, 0x9FBFE4A5L, 0xE8B8D433L, |
125 | 0x7807C9A2L, 0x0F00F934L, 0x9609A88EL, 0xE10E9818L, |
126 | 0x7F6A0DBBL, 0x086D3D2DL, 0x91646C97L, 0xE6635C01L, |
127 | 0x6B6B51F4L, 0x1C6C6162L, 0x856530D8L, 0xF262004EL, |
128 | 0x6C0695EDL, 0x1B01A57BL, 0x8208F4C1L, 0xF50FC457L, |
129 | 0x65B0D9C6L, 0x12B7E950L, 0x8BBEB8EAL, 0xFCB9887CL, |
130 | 0x62DD1DDFL, 0x15DA2D49L, 0x8CD37CF3L, 0xFBD44C65L, |
131 | 0x4DB26158L, 0x3AB551CEL, 0xA3BC0074L, 0xD4BB30E2L, |
132 | 0x4ADFA541L, 0x3DD895D7L, 0xA4D1C46DL, 0xD3D6F4FBL, |
133 | 0x4369E96AL, 0x346ED9FCL, 0xAD678846L, 0xDA60B8D0L, |
134 | 0x44042D73L, 0x33031DE5L, 0xAA0A4C5FL, 0xDD0D7CC9L, |
135 | 0x5005713CL, 0x270241AAL, 0xBE0B1010L, 0xC90C2086L, |
136 | 0x5768B525L, 0x206F85B3L, 0xB966D409L, 0xCE61E49FL, |
137 | 0x5EDEF90EL, 0x29D9C998L, 0xB0D09822L, 0xC7D7A8B4L, |
138 | 0x59B33D17L, 0x2EB40D81L, 0xB7BD5C3BL, 0xC0BA6CADL, |
139 | 0xEDB88320L, 0x9ABFB3B6L, 0x03B6E20CL, 0x74B1D29AL, |
140 | 0xEAD54739L, 0x9DD277AFL, 0x04DB2615L, 0x73DC1683L, |
141 | 0xE3630B12L, 0x94643B84L, 0x0D6D6A3EL, 0x7A6A5AA8L, |
142 | 0xE40ECF0BL, 0x9309FF9DL, 0x0A00AE27L, 0x7D079EB1L, |
143 | 0xF00F9344L, 0x8708A3D2L, 0x1E01F268L, 0x6906C2FEL, |
144 | 0xF762575DL, 0x806567CBL, 0x196C3671L, 0x6E6B06E7L, |
145 | 0xFED41B76L, 0x89D32BE0L, 0x10DA7A5AL, 0x67DD4ACCL, |
146 | 0xF9B9DF6FL, 0x8EBEEFF9L, 0x17B7BE43L, 0x60B08ED5L, |
147 | 0xD6D6A3E8L, 0xA1D1937EL, 0x38D8C2C4L, 0x4FDFF252L, |
148 | 0xD1BB67F1L, 0xA6BC5767L, 0x3FB506DDL, 0x48B2364BL, |
149 | 0xD80D2BDAL, 0xAF0A1B4CL, 0x36034AF6L, 0x41047A60L, |
150 | 0xDF60EFC3L, 0xA867DF55L, 0x316E8EEFL, 0x4669BE79L, |
151 | 0xCB61B38CL, 0xBC66831AL, 0x256FD2A0L, 0x5268E236L, |
152 | 0xCC0C7795L, 0xBB0B4703L, 0x220216B9L, 0x5505262FL, |
153 | 0xC5BA3BBEL, 0xB2BD0B28L, 0x2BB45A92L, 0x5CB36A04L, |
154 | 0xC2D7FFA7L, 0xB5D0CF31L, 0x2CD99E8BL, 0x5BDEAE1DL, |
155 | 0x9B64C2B0L, 0xEC63F226L, 0x756AA39CL, 0x026D930AL, |
156 | 0x9C0906A9L, 0xEB0E363FL, 0x72076785L, 0x05005713L, |
157 | 0x95BF4A82L, 0xE2B87A14L, 0x7BB12BAEL, 0x0CB61B38L, |
158 | 0x92D28E9BL, 0xE5D5BE0DL, 0x7CDCEFB7L, 0x0BDBDF21L, |
159 | 0x86D3D2D4L, 0xF1D4E242L, 0x68DDB3F8L, 0x1FDA836EL, |
160 | 0x81BE16CDL, 0xF6B9265BL, 0x6FB077E1L, 0x18B74777L, |
161 | 0x88085AE6L, 0xFF0F6A70L, 0x66063BCAL, 0x11010B5CL, |
162 | 0x8F659EFFL, 0xF862AE69L, 0x616BFFD3L, 0x166CCF45L, |
163 | 0xA00AE278L, 0xD70DD2EEL, 0x4E048354L, 0x3903B3C2L, |
164 | 0xA7672661L, 0xD06016F7L, 0x4969474DL, 0x3E6E77DBL, |
165 | 0xAED16A4AL, 0xD9D65ADCL, 0x40DF0B66L, 0x37D83BF0L, |
166 | 0xA9BCAE53L, 0xDEBB9EC5L, 0x47B2CF7FL, 0x30B5FFE9L, |
167 | 0xBDBDF21CL, 0xCABAC28AL, 0x53B39330L, 0x24B4A3A6L, |
168 | 0xBAD03605L, 0xCDD70693L, 0x54DE5729L, 0x23D967BFL, |
169 | 0xB3667A2EL, 0xC4614AB8L, 0x5D681B02L, 0x2A6F2B94L, |
170 | 0xB40BBE37L, 0xC30C8EA1L, 0x5A05DF1BL, 0x2D02EF8DL, |
171 | }; |
172 | |
173 | /*****************************************************************/ |
174 | /* End of CRC Lookup Table */ |
175 | /*****************************************************************/ |
176 | |
177 | /* --- Work out the CRC of a bytestring --- */ |
178 | |
179 | #define sym__crc(s_, l_, hv_) do { \ |
180 | unsigned long h_ = 0xFFFFFFFFL; \ |
181 | const char *p_ = s_; \ |
182 | const char *e_ = (s_) + (l_); \ |
183 | \ |
184 | while (p_ < e_) \ |
185 | h_ = (h_ >> 8) ^ (sym__crcTable[(*p_++ ^ h_) & 0xFF]); \ |
186 | hv_ = ~h_ & 0xFFFFFFFFL; \ |
187 | } while (0) |
188 | |
189 | /*----- Main code ---------------------------------------------------------*/ |
190 | |
191 | #ifndef DEBUG_CRC |
192 | |
193 | /* --- @sym_createTable@ --- * |
194 | * |
195 | * Arguments: @sym_table *t@ = symbol table to initialise |
196 | * |
197 | * Returns: --- |
198 | * |
199 | * Use: Initialises the given symbol table. |
200 | */ |
201 | |
202 | void sym_createTable(sym_table *t) |
203 | { |
204 | size_t i; |
205 | |
206 | t->mask = sym__iSize; |
207 | t->c = (sym__iSize * sym__limFactor) >> 8; |
208 | t->a = xmalloc((t->mask + 1) * sizeof(sym_base *)); |
209 | |
210 | for (i = 0; i < sym__iSize + 1; i++) |
211 | t->a[i] = 0; |
212 | } |
213 | |
214 | /* --- @sym_destroyTable@ --- * |
215 | * |
216 | * Arguments: @sym_table *t@ = pointer to symbol table in question |
217 | * |
218 | * Returns: --- |
219 | * |
220 | * Use: Destroys a symbol table, freeing all the memory it used to |
221 | * occupy. |
222 | */ |
223 | |
224 | void sym_destroyTable(sym_table *t) |
225 | { |
226 | size_t i; |
227 | sym_base *p, *q; |
228 | |
229 | for (i = 0; i <= t->mask; i++) { |
230 | p = t->a[i]; |
231 | while (p) { |
232 | q = p->next; |
233 | free(p); |
234 | p = q; |
235 | } |
236 | } |
237 | } |
238 | |
239 | /* --- @sym_find@ --- * |
240 | * |
241 | * Arguments: @sym_table *t@ = pointer to symbol table in question |
242 | * @const char *n@ = pointer to symbol table to look up |
243 | * @long l@ = length of the name string or negative to measure |
244 | * @size_t sz@ = size of desired symbol object, or zero |
245 | * @unsigned *f@ = pointer to a flag, or null. |
246 | * |
247 | * Returns: The address of a @sym_base@ structure, or null if not found |
248 | * and @sz@ is zero. |
249 | * |
250 | * Use: Looks up a symbol in a given symbol table. The name is |
251 | * passed by the address of its first character. The length |
252 | * may be given, in which case the name may contain arbitrary |
253 | * binary data, or it may be given as a negative number, in |
254 | * which case the length of the name is calculated as |
255 | * @strlen(n)@. |
256 | * |
257 | * The return value is the address of a pointer to a @sym_base@ |
258 | * block (which may have other things on the end, as above). If |
259 | * the symbol could be found, the return value points to the |
260 | * symbol block. If the symbol wasn't there, then if @sz@ is |
261 | * nonzero, a new symbol is created and its address is returned; |
262 | * otherwise a null pointer is returned. |
263 | * |
264 | * The value of @*f@ indicates whether a new symbol entry was |
265 | * created: a nonzero value indicates that an old value was |
266 | * found. |
267 | */ |
268 | |
269 | void *sym_find(sym_table *t, const char *n, long l, size_t sz, unsigned *f) |
270 | { |
271 | unsigned long hash; /* Hash value for user's name */ |
272 | size_t len = l < 0 ? strlen(n) + 1 : l; /* Find length of user's name */ |
273 | sym_base *bin; /* Bin containing our item */ |
274 | sym_base *p, *q; /* Pointer wandering through list */ |
275 | |
276 | /* --- Find the correct bin --- */ |
277 | |
278 | sym__crc(n, len, hash); /* Find hash value for this name */ |
279 | bin = p = (sym_base *)(t->a + (hash & t->mask)); |
280 | |
281 | /* --- Search the bin list --- */ |
282 | |
283 | while (p->next) { |
284 | if (hash == p->next->hash && /* Check hash values first */ |
285 | len == p->next->len && /* Then compare string lengths */ |
286 | !memcmp(n, p->next->name, len)) /* And finally compare the strings */ |
287 | { |
288 | /* --- Found a match --- * |
289 | * |
290 | * As a minor, and probably pointless, tweak, move the item to the |
291 | * front of its bin list. |
292 | */ |
293 | |
294 | q = p->next; /* Find the actual symbol block */ |
295 | p->next = q->next; /* Extract block from bin list */ |
296 | q->next = bin->next; /* Set up symbol's next pointer */ |
297 | bin->next = q; /* And reinsert the block */ |
298 | |
299 | /* --- Return the block --- */ |
300 | |
301 | if (f) *f = 1; /* Didn't fail to find the item */ |
302 | return (q); /* And return the block */ |
303 | } |
304 | |
305 | p = p->next; /* Move onto the next item */ |
306 | } |
307 | |
308 | /* --- Couldn't find the item there --- */ |
309 | |
310 | if (f) *f = 0; /* Failed to find the block */ |
311 | if (!sz) return (0); /* Return zero if not creating */ |
312 | |
313 | /* --- Create a new symbol block and initialise it --- */ |
314 | |
315 | p = xmalloc(sz); /* Create a new symbol block */ |
316 | p->next = bin->next; /* Set up the next pointer */ |
317 | p->hash = hash; /* Set up the hash value too */ |
318 | p->name = xmalloc(len); /* Allocate a block for the name */ |
319 | p->len = len; /* And set up the string length */ |
320 | memcpy(p->name, n, len); /* And copy the string over */ |
321 | |
322 | bin->next = p; /* Put the pointer into the bin */ |
323 | |
324 | /* --- Consider growing the array --- */ |
325 | |
326 | if (!--t->c) { |
327 | unsigned long m = t->mask + 1; /* Next set bit in has word */ |
328 | sym_base *p, *q, *r; /* More useful pointers */ |
329 | size_t i, lim; /* Loop counter and limit */ |
330 | |
331 | /* --- Update values in the anchor block --- */ |
332 | |
333 | t->c = ((t->mask + 1) * sym__limFactor) >> 8; /* Set load value */ |
334 | t->mask = (t->mask + 1) * 2 - 1; /* Set the new mask value */ |
335 | t->a = xrealloc(t->a, (t->mask + 1) * sizeof(sym_base *)); |
336 | |
337 | /* --- Now wander through the table rehashing things --- * |
338 | * |
339 | * This loop is very careful to avoid problems with aliasing. The items |
340 | * are dealt with from the end backwards to avoid overwriting bins before |
341 | * they've been processed. |
342 | */ |
343 | |
344 | lim = (t->mask + 1) >> 1; |
345 | for (i = 0; i < lim; i++) { |
346 | /* --- Some initialisation --- */ |
347 | |
348 | r = t->a[i]; /* Find the list we're dissecting */ |
349 | p = (sym_base *)(t->a + i); /* Find bit-clear list */ |
350 | q = (sym_base *)(t->a + i + lim); /* And the bit-set lsit */ |
351 | |
352 | /* --- Now go through the @r@ list --- */ |
353 | |
354 | while (r) { |
355 | if (r->hash & m) /* Is the next bit set? */ |
356 | q = q->next = r; /* Yes, so fit up previous link */ |
357 | else |
358 | p = p->next = r; /* No, so fit up previous link */ |
359 | r = r->next; /* Move onto the next item */ |
360 | } |
361 | p->next = q->next = 0; /* Null terminate the new lists */ |
362 | } |
363 | } |
364 | |
365 | /* --- Finished that, so return the new symbol block --- */ |
366 | |
367 | return (p); |
368 | } |
369 | |
370 | /* --- @sym_remove@ --- * |
371 | * |
372 | * Arguments: @sym_table *i@ = pointer to a symbol table object |
373 | * @void *b@ = pointer to symbol table entry |
374 | * |
375 | * Returns: --- |
376 | * |
377 | * Use: Removes the object from the symbol table. The space occupied |
378 | * by the object and its name is freed; anything else attached |
379 | * to the entry should already be gone by this point. |
380 | */ |
381 | |
382 | void sym_remove(sym_table *t, void *b) |
383 | { |
384 | /* --- A quick comment --- * |
385 | * |
386 | * Since the @sym_base@ block contains the hash, finding the element in the |
387 | * bin list is really quick -- it's not worth bothering with things like |
388 | * doubly linked lists. |
389 | */ |
390 | |
391 | sym_base *p = b; |
392 | sym_base *bin = (sym_base *)(t->a + (p->hash & t->mask)); |
393 | |
394 | /* --- Find the item in the bin list --- */ |
395 | |
396 | while (bin->next) { |
397 | if (bin->next == p) |
398 | break; |
399 | bin = bin->next; |
400 | } |
401 | if (!bin->next) |
402 | return; |
403 | |
404 | /* --- Now just remove the item from the list and free it --- * |
405 | * |
406 | * Oh, and bump the load counter. |
407 | */ |
408 | |
409 | bin->next = p->next; |
410 | free(p->name); |
411 | free(p); |
412 | t->c++; |
413 | } |
414 | |
415 | /* --- @sym_createIter@ --- * |
416 | * |
417 | * Arguments: @sym_iter *i@ = pointer to an iterator object |
418 | * @sym_table *t@ = pointer to a symbol table object |
419 | * |
420 | * Returns: --- |
421 | * |
422 | * Use: Creates a new symbol table iterator which may be used to |
423 | * iterate through a symbol table. |
424 | */ |
425 | |
426 | void sym_createIter(sym_iter *i, sym_table *t) |
427 | { |
428 | i->t = t; |
429 | i->i = 0; |
430 | i->n = 0; |
431 | } |
432 | |
433 | /* --- @sym_next@ --- * |
434 | * |
435 | * Arguments: @sym_iter *i@ = pointer to iterator object |
436 | * |
437 | * Returns: Pointer to the next symbol found, or null when finished. |
438 | * |
439 | * Use: Returns the next symbol from the table. Symbols are not |
440 | * returned in any particular order. |
441 | */ |
442 | |
443 | void *sym_next(sym_iter *i) |
444 | { |
445 | sym_base *p; |
446 | |
447 | /* --- Find the next item --- */ |
448 | |
449 | while (!i->n) { |
450 | if (i->i > i->t->mask) |
451 | return (0); |
452 | i->n = i->t->a[i->i++]; |
453 | } |
454 | |
455 | /* --- Update the iterator block --- */ |
456 | |
457 | p = i->n; |
458 | i->n = p->next; |
459 | |
460 | /* --- Done --- */ |
461 | |
462 | return (p); |
463 | } |
464 | |
465 | #endif |
466 | |
467 | /*----- CRC test code -----------------------------------------------------*/ |
468 | |
469 | #ifdef DEBUG_CRC |
470 | |
471 | int main(void) |
472 | { |
473 | unsigned long h; |
474 | sym__crc("123456789", 9, h); |
475 | printf("crc check == %04x\n", h); |
476 | return (0); |
477 | } |
478 | |
479 | #endif |
480 | |
481 | /*----- Symbol table test code --------------------------------------------*/ |
482 | |
483 | #ifdef TEST_RIG |
484 | |
485 | #include <errno.h> |
486 | #include <time.h> |
487 | |
488 | #include "dbutils.h" |
489 | |
490 | typedef struct sym_word { |
491 | sym_base base; |
492 | size_t i; |
493 | } sym_word; |
494 | |
495 | |
496 | /* --- What it does --- * |
497 | * |
498 | * Reads the file /usr/dict/words (change to some other file full of |
499 | * interesting and appropriate bits of text to taste) into a big buffer and |
500 | * picks apart into lines. Then picks lines at random and enters them into |
501 | * the symbol table. |
502 | */ |
503 | |
504 | int main(void) |
505 | { |
506 | char *buff, *p, *lim; |
507 | size_t sz, done; |
508 | FILE *fp; |
509 | int i; |
510 | char **line; |
511 | sym_word **flag; |
512 | sym_table tbl; |
513 | int entries; |
514 | |
515 | /* --- Initialise for reading the file --- */ |
516 | |
517 | sz = BUFSIZ; |
518 | buff = xmalloc(sz + 1); |
519 | done = 0; |
520 | |
521 | if ((fp = fopen("/usr/dict/words", "r")) == 0) |
522 | fprintf(stderr, "buggered ;-( (%s)\n", strerror(errno)); |
523 | |
524 | /* --- Read buffers of text --- * |
525 | * |
526 | * Read a buffer. If more to come, double the buffer size and try again. |
527 | * This is the method I recommended to comp.lang.c, so I may as well try |
528 | * it. |
529 | */ |
530 | |
531 | for (;;) { |
532 | i = fread(buff + done, 1, sz - done, fp); |
533 | done += i; |
534 | if (done != sz) |
535 | break; |
536 | sz <<= 1; |
537 | buff = xrealloc(buff, sz + 1); |
538 | } |
539 | |
540 | /* --- Count the lines --- */ |
541 | |
542 | lim = buff + done; |
543 | |
544 | sz = 1; |
545 | for (p = buff; p < lim; p++) |
546 | if (*p == '\n') sz++; |
547 | |
548 | /* --- Build a table of line starts --- */ |
549 | |
550 | line = xmalloc(sz * sizeof(char *)); |
551 | i = 0; |
552 | line[i++] = buff; |
553 | for (p = buff; p < lim; p++) |
554 | if (*p == '\n') *p = 0, line[i++] = p + 1; |
555 | *lim = 0; |
556 | |
557 | /* --- Build a table of lines --- * |
558 | * |
559 | * This reverses the mapping which the symbol table performs, so that its |
560 | * accuracy can be tested. |
561 | */ |
562 | |
563 | flag = xmalloc(sz * sizeof(sym_word *)); |
564 | for (i = 0; i < sz; i++) |
565 | flag[i] = 0; |
566 | entries = 0; |
567 | |
568 | sym_createTable(&tbl); |
569 | |
570 | for (;;) { |
571 | i = (unsigned)rand() % sz; |
572 | |
573 | switch (rand() % 5) |
574 | { |
575 | case 0: { |
576 | sym_word *w; |
577 | |
578 | printf("find `%s'\n", line[i]); |
579 | |
580 | w = sym_find(&tbl, line[i], -1, 0, 0); |
581 | if (w != flag[i]) |
582 | printf("*** error: find `%s' gave %p not %p\n", |
583 | line[i], (void *)w, (void *)flag[i]); |
584 | else if (w && w->i != i) |
585 | printf("*** error: find sym for `%s' gives index %i not %i\n", |
586 | line[i], w->i, i); |
587 | } break; |
588 | |
589 | case 1: { |
590 | unsigned f; |
591 | sym_word *w; |
592 | |
593 | printf("create `%s'\n", line[i]); |
594 | |
595 | w = sym_find(&tbl, line[i], -1, sizeof(sym_word), &f); |
596 | if (f) |
597 | { |
598 | if (w != flag[i]) |
599 | printf("*** error: create `%s' gave %p not %p\n", |
600 | line[i], (void *)w, (void *)flag[i]); |
601 | else if (w && w->i != i) |
602 | printf("*** error: create sym for `%s' gives index %i not %i\n", |
603 | line[i], w->i, i); |
604 | } |
605 | else |
606 | { |
607 | if (flag[i]) |
608 | printf("*** error: create `%s' gave new block, should be %p\n", |
609 | line[i], (void *)flag[i]); |
610 | else { |
611 | flag[i] = w; |
612 | w->i = i; |
613 | entries++; |
614 | } |
615 | } |
616 | } break; |
617 | |
618 | case 2: { |
619 | sym_iter it; |
620 | sym_word *w, **ntbl; |
621 | |
622 | printf("iterate\n"); |
623 | |
624 | ntbl = xmalloc(sz * sizeof(sym_word *)); |
625 | memcpy(ntbl, flag, sz * sizeof(sym_word *)); |
626 | sym_createIter(&it, &tbl); |
627 | |
628 | while ((w = sym_next(&it)) != 0) { |
629 | if (ntbl[w->i] == 0) |
630 | printf("*** error: iterate returned duff item %i\n", w->i); |
631 | else |
632 | ntbl[w->i] = 0; |
633 | } |
634 | |
635 | for (i = 0; i < sz; i++) |
636 | if (ntbl[i]) printf("*** error: iterate didn't return item %i\n", |
637 | i); |
638 | free(ntbl); |
639 | } break; |
640 | |
641 | case 3: { |
642 | sym_base *b; |
643 | int v = rand() & 255 ? 0 : 1; |
644 | |
645 | printf("dump\n"); |
646 | |
647 | for (i = 0; i <= tbl.mask; i++) { |
648 | if (!tbl.a[i]) continue; |
649 | if (v) printf(" %i: ", i); |
650 | b = tbl.a[i]; |
651 | while (b) { |
652 | if ((b->hash & tbl.mask) != i) |
653 | printf("*** error: bad hash value found"); |
654 | if (v) printf("`%s'(%08lx:%lu) ", |
655 | line[((sym_word *)b)->i], |
656 | b->hash, |
657 | b->hash & tbl.mask); |
658 | b = b->next; |
659 | } |
660 | if (v) putchar('\n'); |
661 | } |
662 | } break; |
663 | |
664 | case 4: { |
665 | if (flag[i]) { |
666 | printf("remove `%s'\n", flag[i]->base.name); |
667 | sym_remove(&tbl, flag[i]); |
668 | flag[i] = 0; |
669 | entries--; |
670 | } |
671 | } break; |
672 | } |
673 | |
674 | } |
675 | |
676 | return (0); |
677 | } |
678 | |
679 | #endif |
680 | |
681 | /*----- That's all, folks -------------------------------------------------*/ |