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Overview
Comment: | Add the delta_parse(DELTA) table-valued function to the fossildelta extension. |
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Timelines: | family | ancestors | descendants | both | trunk |
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SHA3-256: |
d91fcc267bf1be795dfdb1fbfb40c2ae |
User & Date: | drh 2019-02-19 20:19:51.952 |
Context
2019-02-19
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20:29 | Enhance the xBestIndex method on delta_parse() to return SQLITE_CONSTRAINT if no delta argument is supplied. (check-in: f16d127c3b user: drh tags: trunk) | |
20:19 | Add the delta_parse(DELTA) table-valued function to the fossildelta extension. (check-in: d91fcc267b user: drh tags: trunk) | |
18:39 | Add the fossildelta.c extension in ext/misc with implementations of the Fossil delta functions. (check-in: b80cafa6f8 user: drh tags: trunk) | |
Changes
Changes to ext/misc/fossildelta.c.
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130 131 132 133 134 135 136 | /* ** Read bytes from *pz and convert them into a positive integer. When ** finished, leave *pz pointing to the first character past the end of ** the integer. The *pLen parameter holds the length of the string ** in *pz and is decremented once for each character in the integer. */ | | | 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 | /* ** Read bytes from *pz and convert them into a positive integer. When ** finished, leave *pz pointing to the first character past the end of ** the integer. The *pLen parameter holds the length of the string ** in *pz and is decremented once for each character in the integer. */ static unsigned int deltaGetInt(const char **pz, int *pLen){ static const signed char zValue[] = { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, -1, -1, -1, -1, -1, -1, -1, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, -1, -1, -1, -1, 36, |
︙ | ︙ | |||
480 481 482 483 484 485 486 | ** This routine is provided so that an procedure that is able ** to call delta_apply() can learn how much space is required ** for the output and hence allocate nor more space that is really ** needed. */ static int delta_output_size(const char *zDelta, int lenDelta){ int size; | | | 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 | ** This routine is provided so that an procedure that is able ** to call delta_apply() can learn how much space is required ** for the output and hence allocate nor more space that is really ** needed. */ static int delta_output_size(const char *zDelta, int lenDelta){ int size; size = deltaGetInt(&zDelta, &lenDelta); if( *zDelta!='\n' ){ /* ERROR: size integer not terminated by "\n" */ return -1; } return size; } |
︙ | ︙ | |||
522 523 524 525 526 527 528 | ){ unsigned int limit; unsigned int total = 0; #ifdef FOSSIL_ENABLE_DELTA_CKSUM_TEST char *zOrigOut = zOut; #endif | | | | | 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 | ){ unsigned int limit; unsigned int total = 0; #ifdef FOSSIL_ENABLE_DELTA_CKSUM_TEST char *zOrigOut = zOut; #endif limit = deltaGetInt(&zDelta, &lenDelta); if( *zDelta!='\n' ){ /* ERROR: size integer not terminated by "\n" */ return -1; } zDelta++; lenDelta--; while( *zDelta && lenDelta>0 ){ unsigned int cnt, ofst; cnt = deltaGetInt(&zDelta, &lenDelta); switch( zDelta[0] ){ case '@': { zDelta++; lenDelta--; ofst = deltaGetInt(&zDelta, &lenDelta); if( lenDelta>0 && zDelta[0]!=',' ){ /* ERROR: copy command not terminated by ',' */ return -1; } zDelta++; lenDelta--; total += cnt; if( total>limit ){ |
︙ | ︙ | |||
585 586 587 588 589 590 591 | #endif if( total!=limit ){ /* ERROR: generated size does not match predicted size */ return -1; } return total; } | < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < | 585 586 587 588 589 590 591 592 593 594 595 596 597 598 | #endif if( total!=limit ){ /* ERROR: generated size does not match predicted size */ return -1; } return total; } default: { /* ERROR: unknown delta operator */ return -1; } } } /* ERROR: unterminated delta */ |
︙ | ︙ | |||
761 762 763 764 765 766 767 768 769 770 771 772 773 774 | sqlite3_result_error(context, "corrupt fossil delta", -1); return; }else{ sqlite3_result_int(context, nOut); } } #ifdef _WIN32 __declspec(dllexport) #endif int sqlite3_fossildelta_init( sqlite3 *db, char **pzErrMsg, | > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 | sqlite3_result_error(context, "corrupt fossil delta", -1); return; }else{ sqlite3_result_int(context, nOut); } } /* The deltaparse(DELTA) table-valued function parses the DELTA in ** its input and returns a table that describes that delta. */ typedef struct deltaparsevtab_vtab deltaparsevtab_vtab; typedef struct deltaparsevtab_cursor deltaparsevtab_cursor; struct deltaparsevtab_vtab { sqlite3_vtab base; /* Base class - must be first */ /* No additional information needed */ }; struct deltaparsevtab_cursor { sqlite3_vtab_cursor base; /* Base class - must be first */ char *aDelta; /* The delta being parsed */ int nDelta; /* Number of bytes in the delta */ int iCursor; /* Current cursor location */ int eOp; /* Name of current operator */ unsigned int a1, a2; /* Arguments to current operator */ int iNext; /* Next cursor value */ }; /* Operator names: */ static const char *azOp[] = { "SIZE", "COPY", "INSERT", "CHECKSUM", "ERROR", "EOF" }; #define DELTAPARSE_OP_SIZE 0 #define DELTAPARSE_OP_COPY 1 #define DELTAPARSE_OP_INSERT 2 #define DELTAPARSE_OP_CHECKSUM 3 #define DELTAPARSE_OP_ERROR 4 #define DELTAPARSE_OP_EOF 5 /* ** The deltaparsevtabConnect() method is invoked to create a new ** deltaparse virtual table. ** ** Think of this routine as the constructor for deltaparsevtab_vtab objects. ** ** All this routine needs to do is: ** ** (1) Allocate the deltaparsevtab_vtab object and initialize all fields. ** ** (2) Tell SQLite (via the sqlite3_declare_vtab() interface) what the ** result set of queries against the virtual table will look like. */ static int deltaparsevtabConnect( sqlite3 *db, void *pAux, int argc, const char *const*argv, sqlite3_vtab **ppVtab, char **pzErr ){ deltaparsevtab_vtab *pNew; int rc; rc = sqlite3_declare_vtab(db, "CREATE TABLE x(op,a1,a2,delta HIDDEN)" ); /* For convenience, define symbolic names for the index to each column. */ #define DELTAPARSEVTAB_OP 0 #define DELTAPARSEVTAB_A1 1 #define DELTAPARSEVTAB_A2 2 #define DELTAPARSEVTAB_DELTA 3 if( rc==SQLITE_OK ){ pNew = sqlite3_malloc64( sizeof(*pNew) ); *ppVtab = (sqlite3_vtab*)pNew; if( pNew==0 ) return SQLITE_NOMEM; memset(pNew, 0, sizeof(*pNew)); } return rc; } /* ** This method is the destructor for deltaparsevtab_vtab objects. */ static int deltaparsevtabDisconnect(sqlite3_vtab *pVtab){ deltaparsevtab_vtab *p = (deltaparsevtab_vtab*)pVtab; sqlite3_free(p); return SQLITE_OK; } /* ** Constructor for a new deltaparsevtab_cursor object. */ static int deltaparsevtabOpen(sqlite3_vtab *p, sqlite3_vtab_cursor **ppCursor){ deltaparsevtab_cursor *pCur; pCur = sqlite3_malloc( sizeof(*pCur) ); if( pCur==0 ) return SQLITE_NOMEM; memset(pCur, 0, sizeof(*pCur)); *ppCursor = &pCur->base; return SQLITE_OK; } /* ** Destructor for a deltaparsevtab_cursor. */ static int deltaparsevtabClose(sqlite3_vtab_cursor *cur){ deltaparsevtab_cursor *pCur = (deltaparsevtab_cursor*)cur; sqlite3_free(pCur); return SQLITE_OK; } /* ** Advance a deltaparsevtab_cursor to its next row of output. */ static int deltaparsevtabNext(sqlite3_vtab_cursor *cur){ deltaparsevtab_cursor *pCur = (deltaparsevtab_cursor*)cur; const char *z; int i = 0; pCur->iCursor = pCur->iNext; z = pCur->aDelta + pCur->iCursor; pCur->a1 = deltaGetInt(&z, &i); switch( z[0] ){ case '@': { z++; pCur->a2 = deltaGetInt(&z, &i); pCur->eOp = DELTAPARSE_OP_COPY; pCur->iNext = (int)(&z[1] - pCur->aDelta); break; } case ':': { z++; pCur->a2 = (unsigned int)(z - pCur->aDelta); pCur->eOp = DELTAPARSE_OP_INSERT; pCur->iNext = (int)(&z[pCur->a1] - pCur->aDelta); break; } case ';': { pCur->eOp = DELTAPARSE_OP_CHECKSUM; pCur->iNext = pCur->nDelta; break; } default: { if( pCur->iNext==pCur->nDelta ){ pCur->eOp = DELTAPARSE_OP_EOF; }else{ pCur->eOp = DELTAPARSE_OP_ERROR; pCur->iNext = pCur->nDelta; } break; } } return SQLITE_OK; } /* ** Return values of columns for the row at which the deltaparsevtab_cursor ** is currently pointing. */ static int deltaparsevtabColumn( sqlite3_vtab_cursor *cur, /* The cursor */ sqlite3_context *ctx, /* First argument to sqlite3_result_...() */ int i /* Which column to return */ ){ deltaparsevtab_cursor *pCur = (deltaparsevtab_cursor*)cur; switch( i ){ case DELTAPARSEVTAB_OP: { sqlite3_result_text(ctx, azOp[pCur->eOp], -1, SQLITE_STATIC); break; } case DELTAPARSEVTAB_A1: { sqlite3_result_int(ctx, pCur->a1); break; } case DELTAPARSEVTAB_A2: { if( pCur->eOp==DELTAPARSE_OP_COPY ){ sqlite3_result_int(ctx, pCur->a2); }else if( pCur->eOp==DELTAPARSE_OP_INSERT ){ sqlite3_result_blob(ctx, pCur->aDelta+pCur->a2, pCur->a1, SQLITE_TRANSIENT); } break; } case DELTAPARSEVTAB_DELTA: { sqlite3_result_blob(ctx, pCur->aDelta, pCur->nDelta, SQLITE_TRANSIENT); break; } } return SQLITE_OK; } /* ** Return the rowid for the current row. In this implementation, the ** rowid is the same as the output value. */ static int deltaparsevtabRowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){ deltaparsevtab_cursor *pCur = (deltaparsevtab_cursor*)cur; *pRowid = pCur->iCursor; return SQLITE_OK; } /* ** Return TRUE if the cursor has been moved off of the last ** row of output. */ static int deltaparsevtabEof(sqlite3_vtab_cursor *cur){ deltaparsevtab_cursor *pCur = (deltaparsevtab_cursor*)cur; return pCur->eOp==DELTAPARSE_OP_EOF; } /* ** This method is called to "rewind" the deltaparsevtab_cursor object back ** to the first row of output. This method is always called at least ** once prior to any call to deltaparsevtabColumn() or deltaparsevtabRowid() or ** deltaparsevtabEof(). */ static int deltaparsevtabFilter( sqlite3_vtab_cursor *pVtabCursor, int idxNum, const char *idxStr, int argc, sqlite3_value **argv ){ deltaparsevtab_cursor *pCur = (deltaparsevtab_cursor *)pVtabCursor; const char *a; int i = 0; pCur->eOp = DELTAPARSE_OP_ERROR; if( idxNum!=1 ){ return SQLITE_OK; } pCur->nDelta = sqlite3_value_bytes(argv[0]); a = (const char*)sqlite3_value_blob(argv[0]); if( pCur->nDelta==0 || a==0 ){ return SQLITE_OK; } pCur->aDelta = sqlite3_malloc64( pCur->nDelta+1 ); if( pCur->aDelta==0 ){ pCur->nDelta = 0; return SQLITE_NOMEM; } memcpy(pCur->aDelta, a, pCur->nDelta); pCur->aDelta[pCur->nDelta] = 0; a = pCur->aDelta; pCur->eOp = DELTAPARSE_OP_SIZE; pCur->a1 = deltaGetInt(&a, &i); if( a[0]!='\n' ){ pCur->eOp = DELTAPARSE_OP_ERROR; pCur->a1 = pCur->a2 = 0; pCur->iNext = pCur->nDelta; return SQLITE_OK; } a++; pCur->iNext = (unsigned int)(a - pCur->aDelta); return SQLITE_OK; } /* ** SQLite will invoke this method one or more times while planning a query ** that uses the virtual table. This routine needs to create ** a query plan for each invocation and compute an estimated cost for that ** plan. */ static int deltaparsevtabBestIndex( sqlite3_vtab *tab, sqlite3_index_info *pIdxInfo ){ int i; for(i=0; i<pIdxInfo->nConstraint; i++){ if( pIdxInfo->aConstraint[i].iColumn != DELTAPARSEVTAB_DELTA ) continue; if( pIdxInfo->aConstraint[i].usable==0 ) continue; if( pIdxInfo->aConstraint[i].op!=SQLITE_INDEX_CONSTRAINT_EQ ) continue; pIdxInfo->aConstraintUsage[i].argvIndex = 1; pIdxInfo->aConstraintUsage[i].omit = 1; pIdxInfo->estimatedCost = (double)1; pIdxInfo->estimatedRows = 10; pIdxInfo->idxNum = 1; return SQLITE_OK; } pIdxInfo->idxNum = 0; pIdxInfo->estimatedCost = (double)0x7fffffff; pIdxInfo->estimatedRows = 0x7fffffff; return SQLITE_OK; } /* ** This following structure defines all the methods for the ** virtual table. */ static sqlite3_module deltaparsevtabModule = { /* iVersion */ 0, /* xCreate */ 0, /* xConnect */ deltaparsevtabConnect, /* xBestIndex */ deltaparsevtabBestIndex, /* xDisconnect */ deltaparsevtabDisconnect, /* xDestroy */ 0, /* xOpen */ deltaparsevtabOpen, /* xClose */ deltaparsevtabClose, /* xFilter */ deltaparsevtabFilter, /* xNext */ deltaparsevtabNext, /* xEof */ deltaparsevtabEof, /* xColumn */ deltaparsevtabColumn, /* xRowid */ deltaparsevtabRowid, /* xUpdate */ 0, /* xBegin */ 0, /* xSync */ 0, /* xCommit */ 0, /* xRollback */ 0, /* xFindMethod */ 0, /* xRename */ 0, /* xSavepoint */ 0, /* xRelease */ 0, /* xRollbackTo */ 0, /* xShadowName */ 0 }; #ifdef _WIN32 __declspec(dllexport) #endif int sqlite3_fossildelta_init( sqlite3 *db, char **pzErrMsg, |
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783 784 785 786 787 788 789 790 791 | rc = sqlite3_create_function(db, "delta_apply", 2, SQLITE_UTF8, 0, deltaApplyFunc, 0, 0); } if( rc==SQLITE_OK ){ rc = sqlite3_create_function(db, "delta_output_size", 1, SQLITE_UTF8, 0, deltaOutputSizeFunc, 0, 0); } return rc; } | > > > | 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 | rc = sqlite3_create_function(db, "delta_apply", 2, SQLITE_UTF8, 0, deltaApplyFunc, 0, 0); } if( rc==SQLITE_OK ){ rc = sqlite3_create_function(db, "delta_output_size", 1, SQLITE_UTF8, 0, deltaOutputSizeFunc, 0, 0); } if( rc==SQLITE_OK ){ rc = sqlite3_create_module(db, "delta_parse", &deltaparsevtabModule, 0); } return rc; } |