File: | src/lib/libc/db/hash/hash_bigkey.c |
Warning: | line 200, column 2 Value stored to 'pageno' is never read |
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1 | /* $OpenBSD: hash_bigkey.c,v 1.19 2015/12/28 22:08:18 mmcc Exp $ */ |
2 | |
3 | /*- |
4 | * Copyright (c) 1990, 1993, 1994 |
5 | * The Regents of the University of California. All rights reserved. |
6 | * |
7 | * This code is derived from software contributed to Berkeley by |
8 | * Margo Seltzer. |
9 | * |
10 | * Redistribution and use in source and binary forms, with or without |
11 | * modification, are permitted provided that the following conditions |
12 | * are met: |
13 | * 1. Redistributions of source code must retain the above copyright |
14 | * notice, this list of conditions and the following disclaimer. |
15 | * 2. Redistributions in binary form must reproduce the above copyright |
16 | * notice, this list of conditions and the following disclaimer in the |
17 | * documentation and/or other materials provided with the distribution. |
18 | * 3. Neither the name of the University nor the names of its contributors |
19 | * may be used to endorse or promote products derived from this software |
20 | * without specific prior written permission. |
21 | * |
22 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
23 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
24 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
25 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
26 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
27 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
28 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
29 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
30 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
31 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
32 | * SUCH DAMAGE. |
33 | */ |
34 | |
35 | /* |
36 | * PACKAGE: hash |
37 | * DESCRIPTION: |
38 | * Big key/data handling for the hashing package. |
39 | * |
40 | * ROUTINES: |
41 | * External |
42 | * __big_keydata |
43 | * __big_split |
44 | * __big_insert |
45 | * __big_return |
46 | * __big_delete |
47 | * __find_last_page |
48 | * Internal |
49 | * collect_key |
50 | * collect_data |
51 | */ |
52 | |
53 | #include <errno(*__errno()).h> |
54 | #include <stdio.h> |
55 | #include <stdlib.h> |
56 | #include <string.h> |
57 | |
58 | #ifdef DEBUG |
59 | #include <assert.h> |
60 | #endif |
61 | |
62 | #include <db.h> |
63 | #include "hash.h" |
64 | #include "page.h" |
65 | #include "extern.h" |
66 | |
67 | #define MINIMUM(a, b)(((a) < (b)) ? (a) : (b)) (((a) < (b)) ? (a) : (b)) |
68 | |
69 | static int collect_key(HTAB *, BUFHEAD *, int, DBT *, int); |
70 | static int collect_data(HTAB *, BUFHEAD *, int, int); |
71 | |
72 | /* |
73 | * Big_insert |
74 | * |
75 | * You need to do an insert and the key/data pair is too big |
76 | * |
77 | * Returns: |
78 | * 0 ==> OK |
79 | *-1 ==> ERROR |
80 | */ |
81 | int |
82 | __big_insert(HTAB *hashp, BUFHEAD *bufp, const DBT *key, const DBT *val) |
83 | { |
84 | u_int16_t *p; |
85 | int key_size, n, val_size; |
86 | u_int16_t space, move_bytes, off; |
87 | char *cp, *key_data, *val_data; |
88 | |
89 | cp = bufp->page; /* Character pointer of p. */ |
90 | p = (u_int16_t *)cp; |
91 | |
92 | key_data = (char *)key->data; |
93 | key_size = key->size; |
94 | val_data = (char *)val->data; |
95 | val_size = val->size; |
96 | |
97 | /* First move the Key */ |
98 | for (space = FREESPACE(p)((p)[(p)[0]+1]) - BIGOVERHEAD(4*sizeof(u_int16_t)); key_size; |
99 | space = FREESPACE(p)((p)[(p)[0]+1]) - BIGOVERHEAD(4*sizeof(u_int16_t))) { |
100 | move_bytes = MINIMUM(space, key_size)(((space) < (key_size)) ? (space) : (key_size)); |
101 | off = OFFSET(p)((p)[(p)[0]+2]) - move_bytes; |
102 | memmove(cp + off, key_data, move_bytes); |
103 | key_size -= move_bytes; |
104 | key_data += move_bytes; |
105 | n = p[0]; |
106 | p[++n] = off; |
107 | p[0] = ++n; |
108 | FREESPACE(p)((p)[(p)[0]+1]) = off - PAGE_META(n)(((n)+3) * sizeof(u_int16_t)); |
109 | OFFSET(p)((p)[(p)[0]+2]) = off; |
110 | p[n] = PARTIAL_KEY1; |
111 | bufp = __add_ovflpage(hashp, bufp); |
112 | if (!bufp) |
113 | return (-1); |
114 | n = p[0]; |
115 | if (!key_size) { |
116 | space = FREESPACE(p)((p)[(p)[0]+1]); |
117 | if (space) { |
118 | move_bytes = MINIMUM(space, val_size)(((space) < (val_size)) ? (space) : (val_size)); |
119 | /* |
120 | * If the data would fit exactly in the |
121 | * remaining space, we must overflow it to the |
122 | * next page; otherwise the invariant that the |
123 | * data must end on a page with FREESPACE |
124 | * non-zero would fail. |
125 | */ |
126 | if (space == val_size && val_size == val->size) |
127 | goto toolarge; |
128 | off = OFFSET(p)((p)[(p)[0]+2]) - move_bytes; |
129 | memmove(cp + off, val_data, move_bytes); |
130 | val_data += move_bytes; |
131 | val_size -= move_bytes; |
132 | p[n] = off; |
133 | p[n - 2] = FULL_KEY_DATA3; |
134 | FREESPACE(p)((p)[(p)[0]+1]) = FREESPACE(p)((p)[(p)[0]+1]) - move_bytes; |
135 | OFFSET(p)((p)[(p)[0]+2]) = off; |
136 | } else { |
137 | toolarge: |
138 | p[n - 2] = FULL_KEY2; |
139 | } |
140 | } |
141 | p = (u_int16_t *)bufp->page; |
142 | cp = bufp->page; |
143 | bufp->flags |= BUF_MOD0x0001; |
144 | } |
145 | |
146 | /* Now move the data */ |
147 | for (space = FREESPACE(p)((p)[(p)[0]+1]) - BIGOVERHEAD(4*sizeof(u_int16_t)); val_size; |
148 | space = FREESPACE(p)((p)[(p)[0]+1]) - BIGOVERHEAD(4*sizeof(u_int16_t))) { |
149 | move_bytes = MINIMUM(space, val_size)(((space) < (val_size)) ? (space) : (val_size)); |
150 | /* |
151 | * Here's the hack to make sure that if the data ends on the |
152 | * same page as the key ends, FREESPACE is at least one. |
153 | */ |
154 | if (space == val_size && val_size == val->size) |
155 | move_bytes--; |
156 | off = OFFSET(p)((p)[(p)[0]+2]) - move_bytes; |
157 | memmove(cp + off, val_data, move_bytes); |
158 | val_size -= move_bytes; |
159 | val_data += move_bytes; |
160 | n = p[0]; |
161 | p[++n] = off; |
162 | p[0] = ++n; |
163 | FREESPACE(p)((p)[(p)[0]+1]) = off - PAGE_META(n)(((n)+3) * sizeof(u_int16_t)); |
164 | OFFSET(p)((p)[(p)[0]+2]) = off; |
165 | if (val_size) { |
166 | p[n] = FULL_KEY2; |
167 | bufp = __add_ovflpage(hashp, bufp); |
168 | if (!bufp) |
169 | return (-1); |
170 | cp = bufp->page; |
171 | p = (u_int16_t *)cp; |
172 | } else |
173 | p[n] = FULL_KEY_DATA3; |
174 | bufp->flags |= BUF_MOD0x0001; |
175 | } |
176 | return (0); |
177 | } |
178 | |
179 | /* |
180 | * Called when bufp's page contains a partial key (index should be 1) |
181 | * |
182 | * All pages in the big key/data pair except bufp are freed. We cannot |
183 | * free bufp because the page pointing to it is lost and we can't get rid |
184 | * of its pointer. |
185 | * |
186 | * Returns: |
187 | * 0 => OK |
188 | *-1 => ERROR |
189 | */ |
190 | int |
191 | __big_delete(HTAB *hashp, BUFHEAD *bufp) |
192 | { |
193 | BUFHEAD *last_bfp, *rbufp; |
194 | u_int16_t *bp, pageno; |
195 | int key_done, n; |
196 | |
197 | rbufp = bufp; |
198 | last_bfp = NULL((void *)0); |
199 | bp = (u_int16_t *)bufp->page; |
200 | pageno = 0; |
Value stored to 'pageno' is never read | |
201 | key_done = 0; |
202 | |
203 | while (!key_done || (bp[2] != FULL_KEY_DATA3)) { |
204 | if (bp[2] == FULL_KEY2 || bp[2] == FULL_KEY_DATA3) |
205 | key_done = 1; |
206 | |
207 | /* |
208 | * If there is freespace left on a FULL_KEY_DATA page, then |
209 | * the data is short and fits entirely on this page, and this |
210 | * is the last page. |
211 | */ |
212 | if (bp[2] == FULL_KEY_DATA3 && FREESPACE(bp)((bp)[(bp)[0]+1])) |
213 | break; |
214 | pageno = bp[bp[0] - 1]; |
215 | rbufp->flags |= BUF_MOD0x0001; |
216 | rbufp = __get_buf(hashp, pageno, rbufp, 0); |
217 | if (last_bfp) |
218 | __free_ovflpage(hashp, last_bfp); |
219 | last_bfp = rbufp; |
220 | if (!rbufp) |
221 | return (-1); /* Error. */ |
222 | bp = (u_int16_t *)rbufp->page; |
223 | } |
224 | |
225 | /* |
226 | * If we get here then rbufp points to the last page of the big |
227 | * key/data pair. Bufp points to the first one -- it should now be |
228 | * empty pointing to the next page after this pair. Can't free it |
229 | * because we don't have the page pointing to it. |
230 | */ |
231 | |
232 | /* This is information from the last page of the pair. */ |
233 | n = bp[0]; |
234 | pageno = bp[n - 1]; |
235 | |
236 | /* Now, bp is the first page of the pair. */ |
237 | bp = (u_int16_t *)bufp->page; |
238 | if (n > 2) { |
239 | /* There is an overflow page. */ |
240 | bp[1] = pageno; |
241 | bp[2] = OVFLPAGE0; |
242 | bufp->ovfl = rbufp->ovfl; |
243 | } else |
244 | /* This is the last page. */ |
245 | bufp->ovfl = NULL((void *)0); |
246 | n -= 2; |
247 | bp[0] = n; |
248 | FREESPACE(bp)((bp)[(bp)[0]+1]) = hashp->BSIZEhdr.bsize - PAGE_META(n)(((n)+3) * sizeof(u_int16_t)); |
249 | OFFSET(bp)((bp)[(bp)[0]+2]) = hashp->BSIZEhdr.bsize; |
250 | |
251 | bufp->flags |= BUF_MOD0x0001; |
252 | if (rbufp) |
253 | __free_ovflpage(hashp, rbufp); |
254 | if (last_bfp && last_bfp != rbufp) |
255 | __free_ovflpage(hashp, last_bfp); |
256 | |
257 | hashp->NKEYShdr.nkeys--; |
258 | return (0); |
259 | } |
260 | /* |
261 | * Returns: |
262 | * 0 = key not found |
263 | * -1 = get next overflow page |
264 | * -2 means key not found and this is big key/data |
265 | * -3 error |
266 | */ |
267 | int |
268 | __find_bigpair(HTAB *hashp, BUFHEAD *bufp, int ndx, char *key, int size) |
269 | { |
270 | u_int16_t *bp; |
271 | char *p; |
272 | int ksize; |
273 | u_int16_t bytes; |
274 | char *kkey; |
275 | |
276 | bp = (u_int16_t *)bufp->page; |
277 | p = bufp->page; |
278 | ksize = size; |
279 | kkey = key; |
280 | |
281 | for (bytes = hashp->BSIZEhdr.bsize - bp[ndx]; |
282 | bytes <= size && bp[ndx + 1] == PARTIAL_KEY1; |
283 | bytes = hashp->BSIZEhdr.bsize - bp[ndx]) { |
284 | if (memcmp(p + bp[ndx], kkey, bytes)) |
285 | return (-2); |
286 | kkey += bytes; |
287 | ksize -= bytes; |
288 | bufp = __get_buf(hashp, bp[ndx + 2], bufp, 0); |
289 | if (!bufp) |
290 | return (-3); |
291 | p = bufp->page; |
292 | bp = (u_int16_t *)p; |
293 | ndx = 1; |
294 | } |
295 | |
296 | if (bytes != ksize || memcmp(p + bp[ndx], kkey, bytes)) { |
297 | #ifdef HASH_STATISTICS |
298 | ++hash_collisions; |
299 | #endif |
300 | return (-2); |
301 | } else |
302 | return (ndx); |
303 | } |
304 | |
305 | /* |
306 | * Given the buffer pointer of the first overflow page of a big pair, |
307 | * find the end of the big pair |
308 | * |
309 | * This will set bpp to the buffer header of the last page of the big pair. |
310 | * It will return the pageno of the overflow page following the last page |
311 | * of the pair; 0 if there isn't any (i.e. big pair is the last key in the |
312 | * bucket) |
313 | */ |
314 | u_int16_t |
315 | __find_last_page(HTAB *hashp, BUFHEAD **bpp) |
316 | { |
317 | BUFHEAD *bufp; |
318 | u_int16_t *bp, pageno; |
319 | int n; |
320 | |
321 | bufp = *bpp; |
322 | bp = (u_int16_t *)bufp->page; |
323 | for (;;) { |
324 | n = bp[0]; |
325 | |
326 | /* |
327 | * This is the last page if: the tag is FULL_KEY_DATA and |
328 | * either only 2 entries OVFLPAGE marker is explicit there |
329 | * is freespace on the page. |
330 | */ |
331 | if (bp[2] == FULL_KEY_DATA3 && |
332 | ((n == 2) || (bp[n] == OVFLPAGE0) || (FREESPACE(bp)((bp)[(bp)[0]+1])))) |
333 | break; |
334 | |
335 | pageno = bp[n - 1]; |
336 | bufp = __get_buf(hashp, pageno, bufp, 0); |
337 | if (!bufp) |
338 | return (0); /* Need to indicate an error! */ |
339 | bp = (u_int16_t *)bufp->page; |
340 | } |
341 | |
342 | *bpp = bufp; |
343 | if (bp[0] > 2) |
344 | return (bp[3]); |
345 | else |
346 | return (0); |
347 | } |
348 | |
349 | /* |
350 | * Return the data for the key/data pair that begins on this page at this |
351 | * index (index should always be 1). |
352 | */ |
353 | int |
354 | __big_return(HTAB *hashp, BUFHEAD *bufp, int ndx, DBT *val, int set_current) |
355 | { |
356 | BUFHEAD *save_p; |
357 | u_int16_t *bp, len, off, save_addr; |
358 | char *tp; |
359 | |
360 | bp = (u_int16_t *)bufp->page; |
361 | while (bp[ndx + 1] == PARTIAL_KEY1) { |
362 | bufp = __get_buf(hashp, bp[bp[0] - 1], bufp, 0); |
363 | if (!bufp) |
364 | return (-1); |
365 | bp = (u_int16_t *)bufp->page; |
366 | ndx = 1; |
367 | } |
368 | |
369 | if (bp[ndx + 1] == FULL_KEY2) { |
370 | bufp = __get_buf(hashp, bp[bp[0] - 1], bufp, 0); |
371 | if (!bufp) |
372 | return (-1); |
373 | bp = (u_int16_t *)bufp->page; |
374 | save_p = bufp; |
375 | save_addr = save_p->addr; |
376 | off = bp[1]; |
377 | len = 0; |
378 | } else |
379 | if (!FREESPACE(bp)((bp)[(bp)[0]+1])) { |
380 | /* |
381 | * This is a hack. We can't distinguish between |
382 | * FULL_KEY_DATA that contains complete data or |
383 | * incomplete data, so we require that if the data |
384 | * is complete, there is at least 1 byte of free |
385 | * space left. |
386 | */ |
387 | off = bp[bp[0]]; |
388 | len = bp[1] - off; |
389 | save_p = bufp; |
390 | save_addr = bufp->addr; |
391 | bufp = __get_buf(hashp, bp[bp[0] - 1], bufp, 0); |
392 | if (!bufp) |
393 | return (-1); |
394 | bp = (u_int16_t *)bufp->page; |
395 | } else { |
396 | /* The data is all on one page. */ |
397 | tp = (char *)bp; |
398 | off = bp[bp[0]]; |
399 | val->data = (u_char *)tp + off; |
400 | val->size = bp[1] - off; |
401 | if (set_current) { |
402 | if (bp[0] == 2) { /* No more buckets in |
403 | * chain */ |
404 | hashp->cpage = NULL((void *)0); |
405 | hashp->cbucket++; |
406 | hashp->cndx = 1; |
407 | } else { |
408 | hashp->cpage = __get_buf(hashp, |
409 | bp[bp[0] - 1], bufp, 0); |
410 | if (!hashp->cpage) |
411 | return (-1); |
412 | hashp->cndx = 1; |
413 | if (!((u_int16_t *) |
414 | hashp->cpage->page)[0]) { |
415 | hashp->cbucket++; |
416 | hashp->cpage = NULL((void *)0); |
417 | } |
418 | } |
419 | } |
420 | return (0); |
421 | } |
422 | |
423 | val->size = (size_t)collect_data(hashp, bufp, (int)len, set_current); |
424 | if (val->size == (size_t)-1) |
425 | return (-1); |
426 | if (save_p->addr != save_addr) { |
427 | /* We are pretty short on buffers. */ |
428 | errno(*__errno()) = EINVAL22; /* OUT OF BUFFERS */ |
429 | return (-1); |
430 | } |
431 | memmove(hashp->tmp_buf, (save_p->page) + off, len); |
432 | val->data = (u_char *)hashp->tmp_buf; |
433 | return (0); |
434 | } |
435 | /* |
436 | * Count how big the total datasize is by recursing through the pages. Then |
437 | * allocate a buffer and copy the data as you recurse up. |
438 | */ |
439 | static int |
440 | collect_data(HTAB *hashp, BUFHEAD *bufp, int len, int set) |
441 | { |
442 | u_int16_t *bp; |
443 | char *p; |
444 | BUFHEAD *xbp; |
445 | u_int16_t save_addr; |
446 | int mylen, totlen; |
447 | |
448 | p = bufp->page; |
449 | bp = (u_int16_t *)p; |
450 | mylen = hashp->BSIZEhdr.bsize - bp[1]; |
451 | save_addr = bufp->addr; |
452 | |
453 | if (bp[2] == FULL_KEY_DATA3) { /* End of Data */ |
454 | totlen = len + mylen; |
455 | free(hashp->tmp_buf); |
456 | if ((hashp->tmp_buf = (char *)malloc(totlen)) == NULL((void *)0)) |
457 | return (-1); |
458 | if (set) { |
459 | hashp->cndx = 1; |
460 | if (bp[0] == 2) { /* No more buckets in chain */ |
461 | hashp->cpage = NULL((void *)0); |
462 | hashp->cbucket++; |
463 | } else { |
464 | hashp->cpage = |
465 | __get_buf(hashp, bp[bp[0] - 1], bufp, 0); |
466 | if (!hashp->cpage) |
467 | return (-1); |
468 | else if (!((u_int16_t *)hashp->cpage->page)[0]) { |
469 | hashp->cbucket++; |
470 | hashp->cpage = NULL((void *)0); |
471 | } |
472 | } |
473 | } |
474 | } else { |
475 | xbp = __get_buf(hashp, bp[bp[0] - 1], bufp, 0); |
476 | if (!xbp || ((totlen = |
477 | collect_data(hashp, xbp, len + mylen, set)) < 1)) |
478 | return (-1); |
479 | } |
480 | if (bufp->addr != save_addr) { |
481 | errno(*__errno()) = EINVAL22; /* Out of buffers. */ |
482 | return (-1); |
483 | } |
484 | memmove(&hashp->tmp_buf[len], (bufp->page) + bp[1], mylen); |
485 | return (totlen); |
486 | } |
487 | |
488 | /* |
489 | * Fill in the key and data for this big pair. |
490 | */ |
491 | int |
492 | __big_keydata(HTAB *hashp, BUFHEAD *bufp, DBT *key, DBT *val, int set) |
493 | { |
494 | key->size = (size_t)collect_key(hashp, bufp, 0, val, set); |
495 | if (key->size == (size_t)-1) |
496 | return (-1); |
497 | key->data = (u_char *)hashp->tmp_key; |
498 | return (0); |
499 | } |
500 | |
501 | /* |
502 | * Count how big the total key size is by recursing through the pages. Then |
503 | * collect the data, allocate a buffer and copy the key as you recurse up. |
504 | */ |
505 | static int |
506 | collect_key(HTAB *hashp, BUFHEAD *bufp, int len, DBT *val, int set) |
507 | { |
508 | BUFHEAD *xbp; |
509 | char *p; |
510 | int mylen, totlen; |
511 | u_int16_t *bp, save_addr; |
512 | |
513 | p = bufp->page; |
514 | bp = (u_int16_t *)p; |
515 | mylen = hashp->BSIZEhdr.bsize - bp[1]; |
516 | |
517 | save_addr = bufp->addr; |
518 | totlen = len + mylen; |
519 | if (bp[2] == FULL_KEY2 || bp[2] == FULL_KEY_DATA3) { /* End of Key. */ |
520 | free(hashp->tmp_key); |
521 | if ((hashp->tmp_key = (char *)malloc(totlen)) == NULL((void *)0)) |
522 | return (-1); |
523 | if (__big_return(hashp, bufp, 1, val, set)) |
524 | return (-1); |
525 | } else { |
526 | xbp = __get_buf(hashp, bp[bp[0] - 1], bufp, 0); |
527 | if (!xbp || ((totlen = |
528 | collect_key(hashp, xbp, totlen, val, set)) < 1)) |
529 | return (-1); |
530 | } |
531 | if (bufp->addr != save_addr) { |
532 | errno(*__errno()) = EINVAL22; /* MIS -- OUT OF BUFFERS */ |
533 | return (-1); |
534 | } |
535 | memmove(&hashp->tmp_key[len], (bufp->page) + bp[1], mylen); |
536 | return (totlen); |
537 | } |
538 | |
539 | /* |
540 | * Returns: |
541 | * 0 => OK |
542 | * -1 => error |
543 | */ |
544 | int |
545 | __big_split(HTAB *hashp, |
546 | BUFHEAD *op, /* Pointer to where to put keys that go in old bucket */ |
547 | BUFHEAD *np, /* Pointer to new bucket page */ |
548 | BUFHEAD *big_keyp, /* Pointer to first page containing the big key/data */ |
549 | int addr, /* Address of big_keyp */ |
550 | u_int32_t obucket, /* Old Bucket */ |
551 | SPLIT_RETURN *ret) |
552 | { |
553 | BUFHEAD *bp, *tmpp; |
554 | DBT key, val; |
555 | u_int32_t change; |
556 | u_int16_t free_space, n, off, *tp; |
557 | |
558 | bp = big_keyp; |
559 | |
560 | /* Now figure out where the big key/data goes */ |
561 | if (__big_keydata(hashp, big_keyp, &key, &val, 0)) |
562 | return (-1); |
563 | change = (__call_hash(hashp, key.data, key.size) != obucket); |
564 | |
565 | if ((ret->next_addr = __find_last_page(hashp, &big_keyp))) { |
566 | if (!(ret->nextp = |
567 | __get_buf(hashp, ret->next_addr, big_keyp, 0))) |
568 | return (-1); |
569 | } else |
570 | ret->nextp = NULL((void *)0); |
571 | |
572 | /* Now make one of np/op point to the big key/data pair */ |
573 | #ifdef DEBUG |
574 | assert(np->ovfl == NULL((void *)0)); |
575 | #endif |
576 | if (change) |
577 | tmpp = np; |
578 | else |
579 | tmpp = op; |
580 | |
581 | tmpp->flags |= BUF_MOD0x0001; |
582 | #ifdef DEBUG1 |
583 | (void)fprintf(stderr(&__sF[2]), |
584 | "BIG_SPLIT: %d->ovfl was %d is now %d\n", tmpp->addr, |
585 | (tmpp->ovfl ? tmpp->ovfl->addr : 0), (bp ? bp->addr : 0)); |
586 | #endif |
587 | tmpp->ovfl = bp; /* one of op/np point to big_keyp */ |
588 | tp = (u_int16_t *)tmpp->page; |
589 | #ifdef DEBUG |
590 | assert(FREESPACE(tp)((tp)[(tp)[0]+1]) >= OVFLSIZE(2*sizeof(u_int16_t))); |
591 | #endif |
592 | n = tp[0]; |
593 | off = OFFSET(tp)((tp)[(tp)[0]+2]); |
594 | free_space = FREESPACE(tp)((tp)[(tp)[0]+1]); |
595 | tp[++n] = (u_int16_t)addr; |
596 | tp[++n] = OVFLPAGE0; |
597 | tp[0] = n; |
598 | OFFSET(tp)((tp)[(tp)[0]+2]) = off; |
599 | FREESPACE(tp)((tp)[(tp)[0]+1]) = free_space - OVFLSIZE(2*sizeof(u_int16_t)); |
600 | |
601 | /* |
602 | * Finally, set the new and old return values. BIG_KEYP contains a |
603 | * pointer to the last page of the big key_data pair. Make sure that |
604 | * big_keyp has no following page (2 elements) or create an empty |
605 | * following page. |
606 | */ |
607 | |
608 | ret->newp = np; |
609 | ret->oldp = op; |
610 | |
611 | tp = (u_int16_t *)big_keyp->page; |
612 | big_keyp->flags |= BUF_MOD0x0001; |
613 | if (tp[0] > 2) { |
614 | /* |
615 | * There may be either one or two offsets on this page. If |
616 | * there is one, then the overflow page is linked on normally |
617 | * and tp[4] is OVFLPAGE. If there are two, tp[4] contains |
618 | * the second offset and needs to get stuffed in after the |
619 | * next overflow page is added. |
620 | */ |
621 | n = tp[4]; |
622 | free_space = FREESPACE(tp)((tp)[(tp)[0]+1]); |
623 | off = OFFSET(tp)((tp)[(tp)[0]+2]); |
624 | tp[0] -= 2; |
625 | FREESPACE(tp)((tp)[(tp)[0]+1]) = free_space + OVFLSIZE(2*sizeof(u_int16_t)); |
626 | OFFSET(tp)((tp)[(tp)[0]+2]) = off; |
627 | tmpp = __add_ovflpage(hashp, big_keyp); |
628 | if (!tmpp) |
629 | return (-1); |
630 | tp[4] = n; |
631 | } else |
632 | tmpp = big_keyp; |
633 | |
634 | if (change) |
635 | ret->newp = tmpp; |
636 | else |
637 | ret->oldp = tmpp; |
638 | return (0); |
639 | } |