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Overview
Comment: | :-) (CVS 1712) |
---|---|
Downloads: | Tarball | ZIP archive |
Timelines: | family | ancestors | descendants | both | trunk |
Files: | files | file ages | folders |
SHA1: |
edb01b1275c3de7c398522b5826c8989 |
User & Date: | drh 2001-01-25 01:45:40.000 |
Context
2001-01-29
| ||
01:27 | :-) (CVS 1713) (check-in: 3259a53111 user: drh tags: trunk) | |
2001-01-25
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01:45 | :-) (CVS 1712) (check-in: edb01b1275 user: drh tags: trunk) | |
2001-01-22
| ||
00:31 | :-) (CVS 180) (check-in: 98da825312 user: drh tags: trunk) | |
Changes
Changes to src/db.c.
︙ | ︙ | |||
17 18 19 20 21 22 23 | ** Boston, MA 02111-1307, USA. ** ** Author contact information: ** drh@hwaci.com ** http://www.hwaci.com/drh/ ** ************************************************************************* | | | 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 | ** Boston, MA 02111-1307, USA. ** ** Author contact information: ** drh@hwaci.com ** http://www.hwaci.com/drh/ ** ************************************************************************* ** $Id: db.c,v 1.4 2001/01/25 01:45:40 drh Exp $ */ #include "sqliteInt.h" #include "pg.h" /* ** Everything we need to know about an open database */ |
︙ | ︙ | |||
48 49 50 51 52 53 54 55 56 57 58 59 60 61 | ** this structure. */ typedef struct DbIdxpt DbIdxpt; struct DbIdxpt { int pgno; /* The page number */ u32 *aPage; /* The page data */ int idx; /* Index into pPage[] */ }; /* ** Everything we need to know about a cursor */ struct DbCursor { Db *pDb; /* The whole database */ | > > | 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 | ** this structure. */ typedef struct DbIdxpt DbIdxpt; struct DbIdxpt { int pgno; /* The page number */ u32 *aPage; /* The page data */ int idx; /* Index into pPage[] */ int hashLB; /* Lower bound on hash at this level */ int hashUB; /* Upper bound on hash at this level */ }; /* ** Everything we need to know about a cursor */ struct DbCursor { Db *pDb; /* The whole database */ |
︙ | ︙ | |||
116 117 118 119 120 121 122 123 | ** 0. BLOCK_MAGIC | BLOCK_CONTENTS ** 1. zero ** 2. number of bytes of payload ** 3. freelist ** 4... root pages numbers of tables */ #define U32_PER_PAGE (SQLITE_PAGE_SIZE/sizeof(u32)) | > > > < < > | | > | | | > > > > > > > | | > | > | > > | > | > | | > | | | | > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | < > > | | | > > > > | < | < | < | | | > | > | > | > | | < | | | | < | | < | | | < | | < | > | | > > > > > < | | | < | | | | | < > > > > > > > > > > > > < | | | | | | | < | | | | | | | < < > > > > > | > > > | < | < | < | | | > > > > > > > > > > > > > | > > > > > > > > > > > > > > > > > > > > > > > > > > | | | > > > > > > > > | > > > > > > > > > > > > > > > > > > > | | | > > > > > > > > > > > > > > > > > > > > > > > > > | | < | | < | | > | < | | > | > | > > | > | > | > > > > | < | > > > > > | > > > > | > > > > > | | < > | > > > > | | | < | > > | > | > > > | < < > > > > > > > > > > > | | | | > > | | | > | | | > | > > | > | > > | > > > | > > > < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < | 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 | ** 0. BLOCK_MAGIC | BLOCK_CONTENTS ** 1. zero ** 2. number of bytes of payload ** 3. freelist ** 4... root pages numbers of tables */ /* ** The number of u32-sized objects that will fit on one page. */ #define U32_PER_PAGE (SQLITE_PAGE_SIZE/sizeof(u32)) /* ** Number of direct overflow pages per database entry */ #define N_DIRECT 10 /* ** The maximum amount of payload that will fit on on the same ** page as a leaf, assuming the leaf contains only a single ** database entry and the entry uses no overflow pages. */ #define LOCAL_PAYLOAD (SQLITE_PAGE_SIZE - (8+N_DIRECT)*sizeof(u32)) /* ** Allocate a new page. Return both the page number and a pointer ** to the page data. The calling function is responsible for unref-ing ** the page when it is no longer needed. */ int allocPage(Db *pDb, u32 *pPgno, u32 **ppPage){ u32 pgno; int rc; if( pDb->aContent==0 ) return SQLITE_NOMEM; /* Try to reuse a page from the freelist */ pgno = pDb->aContent[0]; if( pgno!=0 ){ rc = sqlitePgGet(pDb->pPgr, pgno, (void**)ppPage); if( rc==SQLITE_OK ){ pDb->aContent[0] = pFree[1]; *pPgno = pgno; memset(*ppPage, 0, SQLITE_PAGE_SIZE); return SQLITE_OK; } } /* If the freelist is empty, or we cannot access it, ** then allocate a new page from the end of the file. */ if( (rc = sqlitePgCount(pDb->pPgr, &pgno))==SQLITE_OK && (rc = sqlitePgGet(pDb->pPgr, pgno, (void**)ppPage))==SQLITE_OK ){ *pPgno = pgno; memset(*ppPage, 0, SQLITE_PAGE_SIZE); return SQLITE_OK; } return rc; } /* ** Return a page to the freelist and dereference the page. */ static void freePage(DB *pDb, u32 pgno, u32 *aPage){ if( pDb->aContent==0 ) return; if( pgno==0 ) return if( aPage==0 ){ int rc; rc = sqlitePgGet(pDb->pPgr, pgno, &aPage); if( rc!=SQLITE_OK ) return; } aPage[0] = BLOCK_MAGIC | BLOCK_FREE; aPage[1] = pDb->aContent[0]; memset(&aPage[2], 0, SQLITE_PAGE_SIZE - 2*sizeof(u32)); pDb->aContent[0] = pgno; sqlitePgTouch(aPage); sqlitePgUnref(aPage); } /* ** Return the number of bytes of payload storage required on the leaf ** node to hold the amount of payload specified by the argument. ** Overflow pages do not count, only memory on the leaf page. ** ** Return -1 if nTotal is more than sqlite is able to store. */ static int payloadLocalSize(int nTotal){ int nLocal, i; if( nTotal<0 ) nTotal = 0; if( nTotal <= LOCAL_PAYLOAD ){ /* All the data fits on the leaf page */ return (nTotal + 3)/4; } nLocal = LOCAL_PAYLOAD; nTotal -= LOCAL_PAYLOAD; if( nTotal < 10*SQLITE_PAGE_SIZE ){ return nLocal + ((nTotal+SQLITE_PAGE_SIZE-1)/SQLITE_PAGE_SIZE)*sizeof(u32); } nLocal += N_DIRECT*sizeof(u32); nTotal -= N_DIRECT*SQLITE_PAGE_SIZE; if( nTotal < U32_PER_PAGE*SQLITE_PAGE_SIZE ){ return nLocal + sizeof(u32); } nLocal += sizeof(u32); nTotal -= U32_PER_PAGE*SQLITE_PAGE_SIZE; if( nTotal < U32_PER_PAGE*U32_PER_PAGE*SQLITE_PAGE_SIZE ){ return nLocal + sizeof(u32); } return -1; /* This payload will not fit. */ } /* ** Read data from the payload area. ** ** aPage points directly at the beginning of the payload. No bounds ** checking is done on offset or amt -- it is assumed that the payload ** area is big enough to accomodate. */ static int payloadRead(Db *pDb, u32 *aPage, int offset, int amt, void *pBuf){ int rc; int tomove; int i; /* First read local data off of the leaf page itself. ** This is all that ever happens in 99% of accesses. */ assert( offset>=0 && amt>=0 ); if( offset < LOCAL_PAYLOAD ){ /* Data stored directly in the leaf block of the BTree */ if( amt+offset>LOCAL_PAYLOAD ){ tomove = LOCAL_PAYLOAD - offset; }else{ tomove = amt; } memcpy(pBuf, &((char*)aPage)[offset], tomove); pBuf = &((char*)pBuf)[tomove]; offset += tomove; amt -= tomove; if( amt<=0 ) return SQLITE_OK; } offset -= LOCAL_PAYLOAD; aPage += LOCAL_PAYLOAD/sizeof(aPage[0]); /* If not all of the data fits locally, read from the first ** ten direct-access overflow pages. */ if( offset < N_DIRECT*SQLITE_PAGE_SIZE ){ for(i=offset/SQLITE_PAGE_SIZE; i<N_DIRECT && amt>0; i++){ char *aData; base = offset - i*SQLITE_PAGE_SIZE; rc = sqlitePgGet(pDb->pPgr, aPage[i], &aData); if( rc!=SQLITE_OK ) return rc; if( amt+base > SQLITE_PAGE_SIZE ){ tomove = SQLITE_PAGE_SIZE - base; }else{ tomove = amt; } memcpy(pBuf, &aData[base], tomove); sqlitePgUnref(aData); pBuf = &((char*)pBuf)[tomove]; amt -= tomove; } } offset -= N_DIRECT*SQLITE_PAGE_SIZE; aPage += N_DIRECT; /* If the first N_DIRECT overflow pages do not contain everything, then ** read from an overflow page that is filled with pointer to ** U32_PER_PAGE more overflow pages. */ if( offset < U32_PER_PAGE*SQLITE_PAGE_SIZE ){ u32 *indirPage; rc = sqlitePgGet(pDb->pPgr, aPage[0], &indirPage); if( rc!=SQLITE_OK ) return rc; for(i=offset/SQLITE_PAGE_SIZE; i<U32_PER_PAGE && amt>0; i++){ int base; char *aData; base = offset - i*SQLITE_PAGE_SIZE; rc = sqlitePgGet(pDb->pPgr, indirPage[idx], &aData); if( rc!=SQLITE_OK ) break; if( amt+base > SQLITE_PAGE_SIZE ){ tomove = SQLITE_PAGE_SIZE - base; }else{ tomove = amt; } memcpy(pBuf, &aData[base], tomove); sqlitePgUnref(aData); pBuf = &((char*)pBuf)[tomove]; amt -= tomove; } sqlitePgUnref(indirPage); if( rc!=SQLITE_OK ) return rc; if( amt<=0 ) return SQLITE_OK; } offset -= U32_PER_PAGE*SQLITE_PAGE_SIZE; aPage++; /* If there is still more data, then read using a double-indirect ** overflow. The overflow page points to U32_PER_PAGE additional ** overflow pages, each of which pointer to U32_PER_PAGE more overflow ** pages which contain data. ** ** This is hard to test. To exercise this code, you have to make ** a database entry of more than 273336 bytes in side, assuming a ** pagesize of 1024 bytes and 10 direct overflow pages. By the ** time this code runs, you have already used 267 overflow pages. */ if( offset < U32_PER_PAGE*U32_PER_PAGE*SQLITE_PAGE_SIZE ){ u32 *dblIndirPage; rc = sqlitePgGet(pDb->pPgr, aPage[0], &dblIndirPage); if( rc!=SQLITE_OK ) return rc; i = offset/(U32_PER_PAGE*SQLITE_PAGE_SIZE); for(; i<U32_PER_PAGE && amt>0; i++){ u32 *indirPage; int basis; int j; rc = sqlitePgGet(pDb->pPgr, dblIndirPage[i], &indirPage); if( rc!=SQLITE_OK ) break; basis = i*U32_PER_PAGE*SQLITE_PAGE_SIZE; j = (offset - basis)/SQLITE_PAGE_SIZE; for(; j<U32_PER_PAGE && amt>0; j++){ char *aData; base = (offset - basis) - ij*SQLITE_PAGE_SIZE; rc = sqlitePgGet(pDb->pPgr, indirPage[j], &aData); if( rc!=SQLITE_OK ) break; if( amt+base > SQLITE_PAGE_SIZE ){ tomove = SQLITE_PAGE_SIZE - base; }else{ tomove = amt; } memcpy(pBuf, &aData[base], tomove); sqlitePgUnref(aData); pBuf = &((char*)pBuf)[tomove]; amt -= tomove; } sqlitePgUnref(indirPage); if( rc!=SQLITE_OK ) break; } sqlitePgUnref(dblIndirPage); } /* Anything beyond the double-indirect pages, just fill in with ** zeros. You have to write 67382200 bytes to go past the ** double-indirect pages, assuming a 1024 byte page size. */ if( amt>0 ) memset(pBuf, 0, amt); return SQLITE_OK; } /* ** Write data into the payload area. ** ** If pages have already been allocated for the payload, they are ** simply overwritten. New pages are allocated as necessary to ** fill in gaps. sqlitePgTouch() is called on all overflow pages, ** but the calling function must invoke sqlitePgTouch() for aPage ** itself. */ static int payloadWrite(Db *pDb, u32 *aPage, int offset, int amt, void *pBuf){ assert( offset>=0 && amt>=0 ); /* Local data */ if( offset < LOCAL_PAYLOAD ){ if( amt+offset>LOCAL_PAYLOAD ){ tomove = LOCAL_PAYLOAD - offset; }else{ tomove = amt; } memcpy(&((char*)aPage)[offset], pBuf, tomove); pBuf = &((char*)pBuf)[tomove]; offset += tomove; amt -= tomove; if( amt<=0 ) return SQLITE_OK; } offset -= LOCAL_PAYLOAD; aPage += LOCAL_PAYLOAD/sizeof(aPage[0]); /* Direct overflow pages */ if( offset < N_DIRECT*SQLITE_PAGE_SIZE ){ for(i=offset/SQLITE_PAGE_SIZE; i<N_DIRECT && amt>0; i++){ base = offset - i*SQLITE_PAGE_SIZE; if( aPage[i] ){ rc = sqlitePgGet(pDb->pPgr, aPage[i], &aData); }else{ rc = allocPage(pDb, &aPage[i], &aData); } if( rc!=SQLITE_OK ) return rc; if( amt+base > SQLITE_PAGE_SIZE ){ tomove = SQLITE_PAGE_SIZE - base; }else{ tomove = amt; } memcpy(&aData[base], pBuf, tomove); sqlitePgTouch(aData); sqlitePgUnref(aData); pBuf = &((char*)pBuf)[tomove]; amt -= tomove; } if( amt<=0 ) return SQLITE_OK; } offset -= N_DIRECT*SQLITE_PAGE_SIZE; aPage += N_DIRECT; /* Indirect overflow pages */ if( offset < U32_PER_PAGE*SQLITE_PAGE_SIZE ){ u32 *indirPage; if( aPage[0] ){ rc = sqlitePgGet(pDb->pPgr, aPage[0], &indirPage); }else{ rc = allocPage(pDb, &aPage[0], &indirPage); } if( rc!=SQLITE_OK ) return rc; for(i=offset/SQLITE_PAGE_SIZE; i<U32_PER_PAGE && amt>0; i++){ int base; char *aData; base = offset - i*SQLITE_PAGE_SIZE; if( indirPage[i] ){ rc = sqlitePgGet(pDb->pPgr, indirPage[i], &aData); }else{ rc = allocPage(pDb, &indirPage[i], &aData); sqlitePgTouch(indirPage); } if( rc!=SQLITE_OK ) break; if( amt+base > SQLITE_PAGE_SIZE ){ tomove = SQLITE_PAGE_SIZE - base; }else{ tomove = amt; } memcpy(&aData[base], pBuf, tomove); sqlitePgUnref(aData); pBuf = &((char*)pBuf)[tomove]; amt -= tomove; } sqlitePgUnref(indirPage); if( rc!=SQLITE_OK ) return rc; if( amt<=0 ) return SQLITE_OK; } offset -= U32_PER_PAGE*SQLITE_PAGE_SIZE; aPage++; /* Double-indirect overflow pages */ if( offset < U32_PER_PAGE*U32_PER_PAGE*SQLITE_PAGE_SIZE ){ u32 *dblIndirPage; if( aPage[0] ){ rc = sqlitePgGet(pDb->pPgr, aPage[0], &dblIndirPage); }else{ rc = allocPage(pDb, &aPage[0], &dblIndirPage); } if( rc!=SQLITE_OK ) return rc; i = offset/(U32_PER_PAGE*SQLITE_PAGE_SIZE); for(; i<U32_PER_PAGE && amt>0; i++){ u32 *indirPage; int basis; int j; if( aPage[0] ){ rc = sqlitePgGet(pDb->pPgr, aPage[0], &dblIndirPage); }else{ rc = allocPage(pDb, &aPage[0], &dblIndirPage); sqlitePgTouch(dblIndirPage); } rc = sqlitePgGet(pDb->pPgr, dblIndirPage[i], &indirPage); if( rc!=SQLITE_OK ) break; basis = i*U32_PER_PAGE*SQLITE_PAGE_SIZE; j = (offset - basis)/SQLITE_PAGE_SIZE; for(; j<U32_PER_PAGE && amt>0; j++){ char *aData; base = (offset - basis) - ij*SQLITE_PAGE_SIZE; if( indirPage[j] ){ rc = sqlitePgGet(pDb->pPgr, indirPage[j], &aData); }else{ rc = allocPage(pDb, &indirPage[j], &aData); sqlitePgTouch(indirPage); } if( rc!=SQLITE_OK ) break; if( amt+base > SQLITE_PAGE_SIZE ){ tomove = SQLITE_PAGE_SIZE - base; }else{ tomove = amt; } memcpy(&aData[base], pBuf, tomove); sqlitePgTouch(aData); sqlitePgUnref(aData); pBuf = &((char*)pBuf)[tomove]; amt -= tomove; } sqlitePgUnref(indirPage); if( rc!=SQLITE_OK ) break; } sqlitePgUnref(dblIndirPage); } return SQLITE_OK; } /* ** Release any and all overflow pages associated with data starting ** with byte "newSize". oldSize is the amount of payload before doing ** the free operation. */ static int payloadFree(Db *pDb, u32 *aPage, int newSize, int oldSize){ int i, j; /* Loop counters */ int first, last; /* Indices of first and last pages to be freed */ int rc; /* Return code from sqlitePgGet() */ /* Skip over the local data. We do not need to free it. */ if( newSize>=oldSize ) return SQLITE_OK; oldSize -= LOCAL_PAYLOAD; if( oldSize<=0 ) return SQLITE_OK; newSize -= LOCAL_PAYLOAD; aPage += LOCAL_PAYLOAD/sizeof(u32); /* Compute the indices of the first and last overflow pages to ** be freed. */ first = (newSize - 1)/SQLITE_PAGE_SIZE + 1; last = (oldSize - 1)/SQLITE_PAGE_SIZE; /* Free the direct overflow pages */ if( first < N_DIRECT ){ for(i=first; i<N_DIRECT && i<=last; i++){ freePage(pDb, aPage[i], 0); aPage[i] = 0; } } aPage += N_DIRECT; first -= N_DIRECT; last -= N_DIRECT; if( last<0 ) return SQLITE_OK; if( first<0 ) first = 0; /* Free indirect overflow pages */ if( first < U32_PER_PAGE ){ u32 *indirPage; rc = sqlitePgGet(pDb->pPgr, aPage[0], &indirPage); if( rc!=SQLITE_OK ) return rc; for(i=first; i<U32_PER_PAGE && i<=last; i++){ freePage(pDb, indirPage[i], 0); indirPage[i] = 0; touch = 1; } if( first<=0 ){ freepage(pDb, aPage[0], indirPage); aPage[0] = 0; }else{ sqlitePgTouch(indirPage); sqlitePgUnref(indirPage); } } aPage++; first -= U32_PER_PAGE; last -= U32_PER_PAGE; if( last<0 ) return SQLITE_OK; if( first<0 ) first = 0; /* Free double-indirect overflow pages */ if( first < U32_PER_PAGE*U32_PER_PAGE ){ u32 *dblIndirPage; rc = sqlitePgGet(pDb->pPgr, aPage[0], &dblIndirPage); if( rc!=SQLITE_OK ) return rc; for(i=first/U32_PER_PAGE; i<U32_PER_PAGE; i++){ u32 *indirPage; basis = i*U32_PER_PAGE; if( last < basis ) break; rc = sqlitePgGet(pDb->pPgr, dblIndirPage[i], &indirPage); if( rc!=SQLITE_OK ) return rc; for(j=first>basis?first-basis:0 ; j<U32_PER_PAGE; j++){ if( j + basis > last ) break; freePage(pDb, indirPage[j], 0); indirPage[j] = 0; } if( first<=basis ){ freepage(pDb, dblIndirPage[i], 0); dblIndirPage[i] = 0; }else{ sqlitePgTouch(indirPage); sqlitePgUnref(indirPage); } } if( first<=0 ){ freepage(pDb, aPage[0], dblIndirPage); aPage[0] = 0; }else{ sqlitePgTouch(dblIndirPage); sqlitePgUnref(dblIndirPage); } } return SQLITE_OK; } /* ** Allocate space for the content table in the given Db structure. ** return SQLITE_OK on success and SQLITE_NOMEM if it fails. */ static int sqliteDbExpandContent(Db *pDb, int newSize){ if( pDb->nAlloc>=newSize ) return SQLITE_OK; pDb->nAlloc = newSize; pDb->aContent = sqliteRealloc( pDb->aContent, pDb->nAlloc*sizeof(u32)); if( pDb->aContent==0 ){ pDb->nContent = 0; pDb->nAlloc = 0; pDb->inTranaction = 0; return SQLITE_NOMEM; } return SQLITE_OK; } /* ** Open a database. */ int sqliteDbOpen(const char *filename, Db **ppDb){ Db *pDb = 0; Pgr *pPgr = 0; u32 *aPage1; |
︙ | ︙ | |||
585 586 587 588 589 590 591 | int sqliteDbCreateTable(Db *pDb, int *pTblno){ u32 *pPage; u32 pgno; int rc; int swTblno; int i; | | | 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 | int sqliteDbCreateTable(Db *pDb, int *pTblno){ u32 *pPage; u32 pgno; int rc; int swTblno; int i; rc = allocPage(pDb, &pgno, &pPage); if( rc!=SQLITE_OK ){ return rc; } tblno = -1; for(i=2; i<pDb->nContent; i++){ if( pDb->aContent[i]==0 ){ tblno = i - 2; |
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625 626 627 628 629 630 631 | */ static int sqliteDbDropPage(Db *pDb, u32 pgno){ u32 *aPage; int rc; rc = sqlitePgGet(pDb->pPgr, pgno, (void**)&aPage); if( rc!=SQLITE_OK ) return rc; | | | | | | < < < < < < < < < < < < < < < < < < < < < < < < < < | 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 | */ static int sqliteDbDropPage(Db *pDb, u32 pgno){ u32 *aPage; int rc; rc = sqlitePgGet(pDb->pPgr, pgno, (void**)&aPage); if( rc!=SQLITE_OK ) return rc; switch( aPage[0] ){ case BLOCK_MAGIC | BLOCK_INDEX: { int n, i; n = aPage[2]; for(i=0; i<n; i++){ u32 subpgno = aPage[3+i*2]; sqliteDbDropPage(pDb, subpgno); } freePage(pDb, pgno, aPage); break; } case BLOCK_MAGIC | BLOCK_LEAF: { int i = 1; while( i<SQLITE_PAGE_SIZE/sizeof(u32) ){ int entrySize = SWB(aPage[i]); if( entrySize==0 ) break; sqliteDbClearEntry(pDb, &aPage[i]); i += entrySize; } freePage(pDb, pgno, aPage); break; } default: { /* Do nothing */ break; } } } /* ** aEntry points directly at a database entry on a leaf page. ** Free any overflow pages associated with the key or data of ** this entry. */ static int sqliteDbClearEntry(Db *pDb, u32 *aEntry){ return SQLITE_OK; } /* ** Delete the current associate of a cursor and release all the ** pages it holds. Except, do not release pages at levels less ** than N. |
︙ | ︙ | |||
1245 1246 1247 1248 1249 1250 1251 | aPage[i+2] = SWB(nKey); memcpy(&aPage[i+4], pKey, nKey); j = i + 4 + nKeyU; available -= nKeyU; }else{ u32 newPgno, *newPage; aPage[i+2] = SWB(nKey | 0x80000000); | | | | 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 | aPage[i+2] = SWB(nKey); memcpy(&aPage[i+4], pKey, nKey); j = i + 4 + nKeyU; available -= nKeyU; }else{ u32 newPgno, *newPage; aPage[i+2] = SWB(nKey | 0x80000000); rc = allocPage(pCur->pDb, &newPgno, &newPage); if( rc!=SQLITE_OK ) goto write_err; aPage[i+4] = SWB(newPgno); newPage[0] = SWB(BLOCK_MAGIC | BLOCK_OVERFLOW); rc = sqliteDbWriteOvfl(pCur->pDb, newPage, nKey, pKey); if( rc!=SQLITE_OK ) goto write_err; j = i + 5; available -= 1; } if( nDataU <= available ){ aPage[i+3] = SWB(nData); memcpy(&aPage[j], pData, nData); available -= nDataU; j += nDataU; }else{ u32 newPgno, *newPage; aPage[i+3] = SWB(nData | 0x80000000); rc = allocPage(pCur->pDb, &newPgno, &newPage); if( rc!=SQLITE_OK ) goto write_err; aPage[j] = SWB(newPgno); newPage[0] = SWB(BLOCK_MAGIC | BLOCK_OVERFLOW); rc = sqliteDbWriteOvfl(pCur->pDb, newPage, nData, pData); if( rc!=SQLITE_OK ) goto write_err; available -= 1; j++; |
︙ | ︙ |
Changes to src/db.h.
︙ | ︙ | |||
17 18 19 20 21 22 23 | ** Boston, MA 02111-1307, USA. ** ** Author contact information: ** drh@hwaci.com ** http://www.hwaci.com/drh/ ** ************************************************************************* | | | 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 | ** Boston, MA 02111-1307, USA. ** ** Author contact information: ** drh@hwaci.com ** http://www.hwaci.com/drh/ ** ************************************************************************* ** $Id: db.h,v 1.3 2001/01/25 01:45:40 drh Exp $ */ typedef struct Db Db; typedef struct DbCursor DbCursor; int sqliteDbOpen(const char *filename, Db**); int sqliteDbClose(Db*); |
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39 40 41 42 43 44 45 | int sqliteDbCursorOpen(Db*, int tblno, DbCursor**); int sqliteDbCursorClose(DbCursor*); int sqliteDbCursorFirst(DbCursor*); int sqliteDbCursorNext(DbCursor*); int sqliteDbCursorDatasize(DbCursor*); int sqliteDbCursorKeysize(DbCursor*); | | | | | < | < | 39 40 41 42 43 44 45 46 47 48 49 50 | int sqliteDbCursorOpen(Db*, int tblno, DbCursor**); int sqliteDbCursorClose(DbCursor*); int sqliteDbCursorFirst(DbCursor*); int sqliteDbCursorNext(DbCursor*); int sqliteDbCursorDatasize(DbCursor*); int sqliteDbCursorKeysize(DbCursor*); int sqliteDbCursorRead(DbCursor*, int amt, int offset, void *buf); int sqliteDbCursorReadKey(DbCursor*, int amt, int offset, void *buf); int sqliteDbCursorFind(DbCursor*, int nKey, const void *pKey, int createSize); int sqliteDbCursorResize(DbCursor*, int nData); int sqliteDbCursorWrite(DbCursor*, int amt, int offset, const void *buf); |
Changes to src/pg.c.
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17 18 19 20 21 22 23 | ** Boston, MA 02111-1307, USA. ** ** Author contact information: ** drh@hwaci.com ** http://www.hwaci.com/drh/ ** ************************************************************************* | | | 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 | ** Boston, MA 02111-1307, USA. ** ** Author contact information: ** drh@hwaci.com ** http://www.hwaci.com/drh/ ** ************************************************************************* ** $Id: pg.c,v 1.4 2001/01/25 01:45:41 drh Exp $ */ #include <assert.h> #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> #include <unistd.h> #include "sqliteInt.h" |
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252 253 254 255 256 257 258 | ** Look in the journal to see if the given database page is stored ** in the journal. If it is, return its journal page number. If ** not, return 0. */ static u32 sqlitePgJournalPageNumber(Pgr *p, u32 dbpgno){ u32 jpgno; | | | 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 | ** Look in the journal to see if the given database page is stored ** in the journal. If it is, return its journal page number. If ** not, return 0. */ static u32 sqlitePgJournalPageNumber(Pgr *p, u32 dbpgno){ u32 jpgno; if( dbpgno==0 ) return 0; jpgno = p->aJHash[dbpgno % J_HASH_SIZE]; while( jpgno!=0 ){ int idx_num; /* Which journal index describes page jpgno */ int ipgno; /* Page number for the journal index */ int idx_slot; /* Which entry in index idx_num describes jpgno */ Pghdr *pIdxPg; /* The index page for jpgno */ JidxEntry *aIdx; /* The data for the index page */ |
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634 635 636 637 638 639 640 | pPg->pNxHash->pPvHash = pPg; } p->aPgHash[h] = pPg; pPg->jpgno = sqlitePgJournalPageNumber(p, pgno); if( pPg->jpgno!=0 ){ TRACE(("PG: reading d-page %u content from j-page %u\n", pgno, pPg->jpgno)); sqlitePgRead(p->fdJournal, PG_TO_DATA(pPg), pPg->jpgno); | | > > > | 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 | pPg->pNxHash->pPvHash = pPg; } p->aPgHash[h] = pPg; pPg->jpgno = sqlitePgJournalPageNumber(p, pgno); if( pPg->jpgno!=0 ){ TRACE(("PG: reading d-page %u content from j-page %u\n", pgno, pPg->jpgno)); sqlitePgRead(p->fdJournal, PG_TO_DATA(pPg), pPg->jpgno); }else if( pPg->dbpgno!=0 ){ TRACE(("PG: reading d-page %u from database\n", pgno)); sqlitePgRead(p->fdMain, PG_TO_DATA(pPg), pPg->dbpgno); }else{ TRACE(("PG: reading zero page\n"); memset(PG_TO_DATA(pPg), 0, SQLITE_PAGE_SIZE); } pPg->isDirty = 0; pPg->nRef = 1; p->nRefPg++; if( p->nRefPg==1 ){ /* Acquire a read lock */ } |
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687 688 689 690 691 692 693 | return SQLITE_OK; } /* ** Return the number of the first unused page at the end of the ** database file. */ | | | 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 | return SQLITE_OK; } /* ** Return the number of the first unused page at the end of the ** database file. */ int sqlitePgCount(Pgr *p, u32 *pPgno){ *pPgno = p->nDbPg; return SQLITE_OK; } /* ** Return the page number associated with the given page. */ u32 sqlitePgNum(void *pD){ Pghdr *pPg = DATA_TO_PG(pD); return pPg->dbpgno; } |