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Diffstat (limited to 'src/libs/3rdparty/sqlite/carray.c')
| -rw-r--r-- | src/libs/3rdparty/sqlite/carray.c | 403 |
1 files changed, 403 insertions, 0 deletions
diff --git a/src/libs/3rdparty/sqlite/carray.c b/src/libs/3rdparty/sqlite/carray.c new file mode 100644 index 0000000000..09d7676ae6 --- /dev/null +++ b/src/libs/3rdparty/sqlite/carray.c @@ -0,0 +1,403 @@ +/* +** 2016-06-29 +** +** The author disclaims copyright to this source code. In place of +** a legal notice, here is a blessing: +** +** May you do good and not evil. +** May you find forgiveness for yourself and forgive others. +** May you share freely, never taking more than you give. +** +************************************************************************* +** +** This file demonstrates how to create a table-valued-function that +** returns the values in a C-language array. +** Examples: +** +** SELECT * FROM carray($ptr,5) +** +** The query above returns 5 integers contained in a C-language array +** at the address $ptr. $ptr is a pointer to the array of integers. +** The pointer value must be assigned to $ptr using the +** sqlite3_bind_pointer() interface with a pointer type of "carray". +** For example: +** +** static int aX[] = { 53, 9, 17, 2231, 4, 99 }; +** int i = sqlite3_bind_parameter_index(pStmt, "$ptr"); +** sqlite3_bind_pointer(pStmt, i, aX, "carray", 0); +** +** There is an optional third parameter to determine the datatype of +** the C-language array. Allowed values of the third parameter are +** 'int32', 'int64', 'double', 'char*'. Example: +** +** SELECT * FROM carray($ptr,10,'char*'); +** +** The default value of the third parameter is 'int32'. +** +** HOW IT WORKS +** +** The carray "function" is really a virtual table with the +** following schema: +** +** CREATE TABLE carray( +** value, +** pointer HIDDEN, +** count HIDDEN, +** ctype TEXT HIDDEN +** ); +** +** If the hidden columns "pointer" and "count" are unconstrained, then +** the virtual table has no rows. Otherwise, the virtual table interprets +** the integer value of "pointer" as a pointer to the array and "count" +** as the number of elements in the array. The virtual table steps through +** the array, element by element. +*/ +#include "sqlite3ext.h" +SQLITE_EXTENSION_INIT1 +#include <assert.h> +#include <string.h> + +#ifndef SQLITE_OMIT_VIRTUALTABLE + +/* +** Allowed datatypes +*/ +#define CARRAY_INT32 0 +#define CARRAY_INT64 1 +#define CARRAY_DOUBLE 2 +#define CARRAY_TEXT 3 + +/* +** Names of types +*/ +static const char *azType[] = { "int32", "int64", "double", "char*" }; + + +/* carray_cursor is a subclass of sqlite3_vtab_cursor which will +** serve as the underlying representation of a cursor that scans +** over rows of the result +*/ +typedef struct carray_cursor carray_cursor; +struct carray_cursor { + sqlite3_vtab_cursor base; /* Base class - must be first */ + sqlite3_int64 iRowid; /* The rowid */ + void *pPtr; /* Pointer to the array of values */ + sqlite3_int64 iCnt; /* Number of integers in the array */ + unsigned char eType; /* One of the CARRAY_type values */ +}; + +/* +** The carrayConnect() method is invoked to create a new +** carray_vtab that describes the carray virtual table. +** +** Think of this routine as the constructor for carray_vtab objects. +** +** All this routine needs to do is: +** +** (1) Allocate the carray_vtab object and initialize all fields. +** +** (2) Tell SQLite (via the sqlite3_declare_vtab() interface) what the +** result set of queries against carray will look like. +*/ +static int carrayConnect( + sqlite3 *db, + void *pAux, + int argc, const char *const*argv, + sqlite3_vtab **ppVtab, + char **pzErr +){ + sqlite3_vtab *pNew; + int rc; + +/* Column numbers */ +#define CARRAY_COLUMN_VALUE 0 +#define CARRAY_COLUMN_POINTER 1 +#define CARRAY_COLUMN_COUNT 2 +#define CARRAY_COLUMN_CTYPE 3 + + rc = sqlite3_declare_vtab(db, + "CREATE TABLE x(value,pointer hidden,count hidden,ctype hidden)"); + if( rc==SQLITE_OK ){ + pNew = *ppVtab = sqlite3_malloc( sizeof(*pNew) ); + if( pNew==0 ) return SQLITE_NOMEM; + memset(pNew, 0, sizeof(*pNew)); + } + return rc; +} + +/* +** This method is the destructor for carray_cursor objects. +*/ +static int carrayDisconnect(sqlite3_vtab *pVtab){ + sqlite3_free(pVtab); + return SQLITE_OK; +} + +/* +** Constructor for a new carray_cursor object. +*/ +static int carrayOpen(sqlite3_vtab *p, sqlite3_vtab_cursor **ppCursor) +{ + carray_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 carray_cursor. +*/ +static int carrayClose(sqlite3_vtab_cursor *cur){ + sqlite3_free(cur); + return SQLITE_OK; +} + + +/* +** Advance a carray_cursor to its next row of output. +*/ +static int carrayNext(sqlite3_vtab_cursor *cur){ + carray_cursor *pCur = (carray_cursor*)cur; + pCur->iRowid++; + return SQLITE_OK; +} + +/* +** Return values of columns for the row at which the carray_cursor +** is currently pointing. +*/ +static int carrayColumn( + sqlite3_vtab_cursor *cur, /* The cursor */ + sqlite3_context *ctx, /* First argument to sqlite3_result_...() */ + int i /* Which column to return */ +){ + carray_cursor *pCur = (carray_cursor*)cur; + sqlite3_int64 x = 0; + switch( i ){ + case CARRAY_COLUMN_POINTER: return SQLITE_OK; + case CARRAY_COLUMN_COUNT: x = pCur->iCnt; break; + case CARRAY_COLUMN_CTYPE: { + sqlite3_result_text(ctx, azType[pCur->eType], -1, SQLITE_STATIC); + return SQLITE_OK; + } + default: { + switch( pCur->eType ){ + case CARRAY_INT32: { + int *p = (int*)pCur->pPtr; + sqlite3_result_int(ctx, p[pCur->iRowid-1]); + return SQLITE_OK; + } + case CARRAY_INT64: { + sqlite3_int64 *p = (sqlite3_int64*)pCur->pPtr; + sqlite3_result_int64(ctx, p[pCur->iRowid-1]); + return SQLITE_OK; + } + case CARRAY_DOUBLE: { + double *p = (double*)pCur->pPtr; + sqlite3_result_double(ctx, p[pCur->iRowid-1]); + return SQLITE_OK; + } + case CARRAY_TEXT: { + const char **p = (const char**)pCur->pPtr; + sqlite3_result_text(ctx, p[pCur->iRowid-1], -1, SQLITE_TRANSIENT); + return SQLITE_OK; + } + } + } + } + sqlite3_result_int64(ctx, x); + return SQLITE_OK; +} + +/* +** Return the rowid for the current row. In this implementation, the +** rowid is the same as the output value. +*/ +static int carrayRowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){ + carray_cursor *pCur = (carray_cursor*)cur; + *pRowid = pCur->iRowid; + return SQLITE_OK; +} + +/* +** Return TRUE if the cursor has been moved off of the last +** row of output. +*/ +static int carrayEof(sqlite3_vtab_cursor *cur){ + carray_cursor *pCur = (carray_cursor*)cur; + return pCur->iRowid>pCur->iCnt; +} + +/* +** This method is called to "rewind" the carray_cursor object back +** to the first row of output. +*/ +static int carrayFilter( + sqlite3_vtab_cursor *pVtabCursor, + int idxNum, const char *idxStr, + int argc, sqlite3_value **argv +){ + carray_cursor *pCur = (carray_cursor *)pVtabCursor; + if( idxNum ){ + pCur->pPtr = sqlite3_value_pointer(argv[0], "carray"); + pCur->iCnt = pCur->pPtr ? sqlite3_value_int64(argv[1]) : 0; + if( idxNum<3 ){ + pCur->eType = CARRAY_INT32; + }else{ + unsigned char i; + const char *zType = (const char*)sqlite3_value_text(argv[2]); + for(i=0; i<sizeof(azType)/sizeof(azType[0]); i++){ + if( sqlite3_stricmp(zType, azType[i])==0 ) break; + } + if( i>=sizeof(azType)/sizeof(azType[0]) ){ + pVtabCursor->pVtab->zErrMsg = sqlite3_mprintf( + "unknown datatype: %Q", zType); + return SQLITE_ERROR; + }else{ + pCur->eType = i; + } + } + }else{ + pCur->pPtr = 0; + pCur->iCnt = 0; + } + pCur->iRowid = 1; + return SQLITE_OK; +} + +/* +** SQLite will invoke this method one or more times while planning a query +** that uses the carray virtual table. This routine needs to create +** a query plan for each invocation and compute an estimated cost for that +** plan. +** +** In this implementation idxNum is used to represent the +** query plan. idxStr is unused. +** +** idxNum is 2 if the pointer= and count= constraints exist, +** 3 if the ctype= constraint also exists, and is 0 otherwise. +** If idxNum is 0, then carray becomes an empty table. +*/ +static int carrayBestIndex( + sqlite3_vtab *tab, + sqlite3_index_info *pIdxInfo +){ + int i; /* Loop over constraints */ + int ptrIdx = -1; /* Index of the pointer= constraint, or -1 if none */ + int cntIdx = -1; /* Index of the count= constraint, or -1 if none */ + int ctypeIdx = -1; /* Index of the ctype= constraint, or -1 if none */ + + const struct sqlite3_index_constraint *pConstraint; + pConstraint = pIdxInfo->aConstraint; + for(i=0; i<pIdxInfo->nConstraint; i++, pConstraint++){ + if( pConstraint->usable==0 ) continue; + if( pConstraint->op!=SQLITE_INDEX_CONSTRAINT_EQ ) continue; + switch( pConstraint->iColumn ){ + case CARRAY_COLUMN_POINTER: + ptrIdx = i; + break; + case CARRAY_COLUMN_COUNT: + cntIdx = i; + break; + case CARRAY_COLUMN_CTYPE: + ctypeIdx = i; + break; + } + } + if( ptrIdx>=0 && cntIdx>=0 ){ + pIdxInfo->aConstraintUsage[ptrIdx].argvIndex = 1; + pIdxInfo->aConstraintUsage[ptrIdx].omit = 1; + pIdxInfo->aConstraintUsage[cntIdx].argvIndex = 2; + pIdxInfo->aConstraintUsage[cntIdx].omit = 1; + pIdxInfo->estimatedCost = (double)1; + pIdxInfo->estimatedRows = 100; + pIdxInfo->idxNum = 2; + if( ctypeIdx>=0 ){ + pIdxInfo->aConstraintUsage[ctypeIdx].argvIndex = 3; + pIdxInfo->aConstraintUsage[ctypeIdx].omit = 1; + pIdxInfo->idxNum = 3; + } + }else{ + pIdxInfo->estimatedCost = (double)2147483647; + pIdxInfo->estimatedRows = 2147483647; + pIdxInfo->idxNum = 0; + } + return SQLITE_OK; +} + +/* +** This following structure defines all the methods for the +** carray virtual table. +*/ +static sqlite3_module carrayModule = { + 0, /* iVersion */ + 0, /* xCreate */ + carrayConnect, /* xConnect */ + carrayBestIndex, /* xBestIndex */ + carrayDisconnect, /* xDisconnect */ + 0, /* xDestroy */ + carrayOpen, /* xOpen - open a cursor */ + carrayClose, /* xClose - close a cursor */ + carrayFilter, /* xFilter - configure scan constraints */ + carrayNext, /* xNext - advance a cursor */ + carrayEof, /* xEof - check for end of scan */ + carrayColumn, /* xColumn - read data */ + carrayRowid, /* xRowid - read data */ + 0, /* xUpdate */ + 0, /* xBegin */ + 0, /* xSync */ + 0, /* xCommit */ + 0, /* xRollback */ + 0, /* xFindMethod */ + 0, /* xRename */ +}; + +/* +** For testing purpose in the TCL test harness, we need a method for +** setting the pointer value. The inttoptr(X) SQL function accomplishes +** this. Tcl script will bind an integer to X and the inttoptr() SQL +** function will use sqlite3_result_pointer() to convert that integer into +** a pointer. +** +** This is for testing on TCL only. +*/ +#ifdef SQLITE_TEST +static void inttoptrFunc( + sqlite3_context *context, + int argc, + sqlite3_value **argv +){ + void *p; + sqlite3_int64 i64; + i64 = sqlite3_value_int64(argv[0]); + if( sizeof(i64)==sizeof(p) ){ + memcpy(&p, &i64, sizeof(p)); + }else{ + int i32 = i64 & 0xffffffff; + memcpy(&p, &i32, sizeof(p)); + } + sqlite3_result_pointer(context, p, "carray", 0); +} +#endif /* SQLITE_TEST */ + +#endif /* SQLITE_OMIT_VIRTUALTABLE */ + +int sqlite3_carray_init(sqlite3 *db, char **pzErrMsg, const sqlite3_api_routines *pApi) +{ + int rc = SQLITE_OK; + SQLITE_EXTENSION_INIT2(pApi); +#ifndef SQLITE_OMIT_VIRTUALTABLE + rc = sqlite3_create_module(db, "carray", &carrayModule, 0); + +#ifdef SQLITE_TEST + if (rc == SQLITE_OK) { + rc = sqlite3_create_function(db, "inttoptr", 1, SQLITE_UTF8, 0, inttoptrFunc, 0, 0); + } +#endif /* SQLITE_TEST */ +#endif /* SQLITE_OMIT_VIRTUALTABLE */ + return rc; +} |