diff options
Diffstat (limited to 'vendor/github.com/mattn/go-sqlite3/sqlite3_vtable.go')
| -rw-r--r-- | vendor/github.com/mattn/go-sqlite3/sqlite3_vtable.go | 646 |
1 files changed, 646 insertions, 0 deletions
diff --git a/vendor/github.com/mattn/go-sqlite3/sqlite3_vtable.go b/vendor/github.com/mattn/go-sqlite3/sqlite3_vtable.go new file mode 100644 index 0000000..8bef291 --- /dev/null +++ b/vendor/github.com/mattn/go-sqlite3/sqlite3_vtable.go @@ -0,0 +1,646 @@ +// Copyright (C) 2014 Yasuhiro Matsumoto <mattn.jp@gmail.com>. +// +// Use of this source code is governed by an MIT-style +// license that can be found in the LICENSE file. +// +build vtable + +package sqlite3 + +/* +#cgo CFLAGS: -std=gnu99 +#cgo CFLAGS: -DSQLITE_ENABLE_RTREE -DSQLITE_THREADSAFE +#cgo CFLAGS: -DSQLITE_ENABLE_FTS3 -DSQLITE_ENABLE_FTS3_PARENTHESIS -DSQLITE_ENABLE_FTS4_UNICODE61 +#cgo CFLAGS: -DSQLITE_TRACE_SIZE_LIMIT=15 +#cgo CFLAGS: -DSQLITE_ENABLE_COLUMN_METADATA=1 +#cgo CFLAGS: -Wno-deprecated-declarations + +#ifndef USE_LIBSQLITE3 +#include <sqlite3-binding.h> +#else +#include <sqlite3.h> +#endif +#include <stdlib.h> +#include <stdint.h> +#include <memory.h> + +static inline char *_sqlite3_mprintf(char *zFormat, char *arg) { + return sqlite3_mprintf(zFormat, arg); +} + +typedef struct goVTab goVTab; + +struct goVTab { + sqlite3_vtab base; + void *vTab; +}; + +uintptr_t goMInit(void *db, void *pAux, int argc, char **argv, char **pzErr, int isCreate); + +static int cXInit(sqlite3 *db, void *pAux, int argc, const char *const*argv, sqlite3_vtab **ppVTab, char **pzErr, int isCreate) { + void *vTab = (void *)goMInit(db, pAux, argc, (char**)argv, pzErr, isCreate); + if (!vTab || *pzErr) { + return SQLITE_ERROR; + } + goVTab *pvTab = (goVTab *)sqlite3_malloc(sizeof(goVTab)); + if (!pvTab) { + *pzErr = sqlite3_mprintf("%s", "Out of memory"); + return SQLITE_NOMEM; + } + memset(pvTab, 0, sizeof(goVTab)); + pvTab->vTab = vTab; + + *ppVTab = (sqlite3_vtab *)pvTab; + *pzErr = 0; + return SQLITE_OK; +} + +static inline int cXCreate(sqlite3 *db, void *pAux, int argc, const char *const*argv, sqlite3_vtab **ppVTab, char **pzErr) { + return cXInit(db, pAux, argc, argv, ppVTab, pzErr, 1); +} +static inline int cXConnect(sqlite3 *db, void *pAux, int argc, const char *const*argv, sqlite3_vtab **ppVTab, char **pzErr) { + return cXInit(db, pAux, argc, argv, ppVTab, pzErr, 0); +} + +char* goVBestIndex(void *pVTab, void *icp); + +static inline int cXBestIndex(sqlite3_vtab *pVTab, sqlite3_index_info *info) { + char *pzErr = goVBestIndex(((goVTab*)pVTab)->vTab, info); + if (pzErr) { + if (pVTab->zErrMsg) + sqlite3_free(pVTab->zErrMsg); + pVTab->zErrMsg = pzErr; + return SQLITE_ERROR; + } + return SQLITE_OK; +} + +char* goVRelease(void *pVTab, int isDestroy); + +static int cXRelease(sqlite3_vtab *pVTab, int isDestroy) { + char *pzErr = goVRelease(((goVTab*)pVTab)->vTab, isDestroy); + if (pzErr) { + if (pVTab->zErrMsg) + sqlite3_free(pVTab->zErrMsg); + pVTab->zErrMsg = pzErr; + return SQLITE_ERROR; + } + if (pVTab->zErrMsg) + sqlite3_free(pVTab->zErrMsg); + sqlite3_free(pVTab); + return SQLITE_OK; +} + +static inline int cXDisconnect(sqlite3_vtab *pVTab) { + return cXRelease(pVTab, 0); +} +static inline int cXDestroy(sqlite3_vtab *pVTab) { + return cXRelease(pVTab, 1); +} + +typedef struct goVTabCursor goVTabCursor; + +struct goVTabCursor { + sqlite3_vtab_cursor base; + void *vTabCursor; +}; + +uintptr_t goVOpen(void *pVTab, char **pzErr); + +static int cXOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor) { + void *vTabCursor = (void *)goVOpen(((goVTab*)pVTab)->vTab, &(pVTab->zErrMsg)); + goVTabCursor *pCursor = (goVTabCursor *)sqlite3_malloc(sizeof(goVTabCursor)); + if (!pCursor) { + return SQLITE_NOMEM; + } + memset(pCursor, 0, sizeof(goVTabCursor)); + pCursor->vTabCursor = vTabCursor; + *ppCursor = (sqlite3_vtab_cursor *)pCursor; + return SQLITE_OK; +} + +static int setErrMsg(sqlite3_vtab_cursor *pCursor, char *pzErr) { + if (pCursor->pVtab->zErrMsg) + sqlite3_free(pCursor->pVtab->zErrMsg); + pCursor->pVtab->zErrMsg = pzErr; + return SQLITE_ERROR; +} + +char* goVClose(void *pCursor); + +static int cXClose(sqlite3_vtab_cursor *pCursor) { + char *pzErr = goVClose(((goVTabCursor*)pCursor)->vTabCursor); + if (pzErr) { + return setErrMsg(pCursor, pzErr); + } + sqlite3_free(pCursor); + return SQLITE_OK; +} + +char* goVFilter(void *pCursor, int idxNum, char* idxName, int argc, sqlite3_value **argv); + +static int cXFilter(sqlite3_vtab_cursor *pCursor, int idxNum, const char *idxStr, int argc, sqlite3_value **argv) { + char *pzErr = goVFilter(((goVTabCursor*)pCursor)->vTabCursor, idxNum, (char*)idxStr, argc, argv); + if (pzErr) { + return setErrMsg(pCursor, pzErr); + } + return SQLITE_OK; +} + +char* goVNext(void *pCursor); + +static int cXNext(sqlite3_vtab_cursor *pCursor) { + char *pzErr = goVNext(((goVTabCursor*)pCursor)->vTabCursor); + if (pzErr) { + return setErrMsg(pCursor, pzErr); + } + return SQLITE_OK; +} + +int goVEof(void *pCursor); + +static inline int cXEof(sqlite3_vtab_cursor *pCursor) { + return goVEof(((goVTabCursor*)pCursor)->vTabCursor); +} + +char* goVColumn(void *pCursor, void *cp, int col); + +static int cXColumn(sqlite3_vtab_cursor *pCursor, sqlite3_context *ctx, int i) { + char *pzErr = goVColumn(((goVTabCursor*)pCursor)->vTabCursor, ctx, i); + if (pzErr) { + return setErrMsg(pCursor, pzErr); + } + return SQLITE_OK; +} + +char* goVRowid(void *pCursor, sqlite3_int64 *pRowid); + +static int cXRowid(sqlite3_vtab_cursor *pCursor, sqlite3_int64 *pRowid) { + char *pzErr = goVRowid(((goVTabCursor*)pCursor)->vTabCursor, pRowid); + if (pzErr) { + return setErrMsg(pCursor, pzErr); + } + return SQLITE_OK; +} + +char* goVUpdate(void *pVTab, int argc, sqlite3_value **argv, sqlite3_int64 *pRowid); + +static int cXUpdate(sqlite3_vtab *pVTab, int argc, sqlite3_value **argv, sqlite3_int64 *pRowid) { + char *pzErr = goVUpdate(((goVTab*)pVTab)->vTab, argc, argv, pRowid); + if (pzErr) { + if (pVTab->zErrMsg) + sqlite3_free(pVTab->zErrMsg); + pVTab->zErrMsg = pzErr; + return SQLITE_ERROR; + } + return SQLITE_OK; +} + +static sqlite3_module goModule = { + 0, // iVersion + cXCreate, // xCreate - create a table + cXConnect, // xConnect - connect to an existing table + cXBestIndex, // xBestIndex - Determine search strategy + cXDisconnect, // xDisconnect - Disconnect from a table + cXDestroy, // xDestroy - Drop a table + cXOpen, // xOpen - open a cursor + cXClose, // xClose - close a cursor + cXFilter, // xFilter - configure scan constraints + cXNext, // xNext - advance a cursor + cXEof, // xEof + cXColumn, // xColumn - read data + cXRowid, // xRowid - read data + cXUpdate, // xUpdate - write data +// Not implemented + 0, // xBegin - begin transaction + 0, // xSync - sync transaction + 0, // xCommit - commit transaction + 0, // xRollback - rollback transaction + 0, // xFindFunction - function overloading + 0, // xRename - rename the table + 0, // xSavepoint + 0, // xRelease + 0 // xRollbackTo +}; + +void goMDestroy(void*); + +static int _sqlite3_create_module(sqlite3 *db, const char *zName, uintptr_t pClientData) { + return sqlite3_create_module_v2(db, zName, &goModule, (void*) pClientData, goMDestroy); +} +*/ +import "C" + +import ( + "fmt" + "math" + "reflect" + "unsafe" +) + +type sqliteModule struct { + c *SQLiteConn + name string + module Module +} + +type sqliteVTab struct { + module *sqliteModule + vTab VTab +} + +type sqliteVTabCursor struct { + vTab *sqliteVTab + vTabCursor VTabCursor +} + +// Op is type of operations. +type Op uint8 + +// Op mean identity of operations. +const ( + OpEQ Op = 2 + OpGT = 4 + OpLE = 8 + OpLT = 16 + OpGE = 32 + OpMATCH = 64 + OpLIKE = 65 /* 3.10.0 and later only */ + OpGLOB = 66 /* 3.10.0 and later only */ + OpREGEXP = 67 /* 3.10.0 and later only */ + OpScanUnique = 1 /* Scan visits at most 1 row */ +) + +// InfoConstraint give information of constraint. +type InfoConstraint struct { + Column int + Op Op + Usable bool +} + +// InfoOrderBy give information of order-by. +type InfoOrderBy struct { + Column int + Desc bool +} + +func constraints(info *C.sqlite3_index_info) []InfoConstraint { + l := info.nConstraint + slice := (*[1 << 30]C.struct_sqlite3_index_constraint)(unsafe.Pointer(info.aConstraint))[:l:l] + + cst := make([]InfoConstraint, 0, l) + for _, c := range slice { + var usable bool + if c.usable > 0 { + usable = true + } + cst = append(cst, InfoConstraint{ + Column: int(c.iColumn), + Op: Op(c.op), + Usable: usable, + }) + } + return cst +} + +func orderBys(info *C.sqlite3_index_info) []InfoOrderBy { + l := info.nOrderBy + slice := (*[1 << 30]C.struct_sqlite3_index_orderby)(unsafe.Pointer(info.aOrderBy))[:l:l] + + ob := make([]InfoOrderBy, 0, l) + for _, c := range slice { + var desc bool + if c.desc > 0 { + desc = true + } + ob = append(ob, InfoOrderBy{ + Column: int(c.iColumn), + Desc: desc, + }) + } + return ob +} + +// IndexResult is a Go struct representation of what eventually ends up in the +// output fields for `sqlite3_index_info` +// See: https://www.sqlite.org/c3ref/index_info.html +type IndexResult struct { + Used []bool // aConstraintUsage + IdxNum int + IdxStr string + AlreadyOrdered bool // orderByConsumed + EstimatedCost float64 + EstimatedRows float64 +} + +// mPrintf is a utility wrapper around sqlite3_mprintf +func mPrintf(format, arg string) *C.char { + cf := C.CString(format) + defer C.free(unsafe.Pointer(cf)) + ca := C.CString(arg) + defer C.free(unsafe.Pointer(ca)) + return C._sqlite3_mprintf(cf, ca) +} + +//export goMInit +func goMInit(db, pClientData unsafe.Pointer, argc C.int, argv **C.char, pzErr **C.char, isCreate C.int) C.uintptr_t { + m := lookupHandle(uintptr(pClientData)).(*sqliteModule) + if m.c.db != (*C.sqlite3)(db) { + *pzErr = mPrintf("%s", "Inconsistent db handles") + return 0 + } + args := make([]string, argc) + var A []*C.char + slice := reflect.SliceHeader{Data: uintptr(unsafe.Pointer(argv)), Len: int(argc), Cap: int(argc)} + a := reflect.NewAt(reflect.TypeOf(A), unsafe.Pointer(&slice)).Elem().Interface() + for i, s := range a.([]*C.char) { + args[i] = C.GoString(s) + } + var vTab VTab + var err error + if isCreate == 1 { + vTab, err = m.module.Create(m.c, args) + } else { + vTab, err = m.module.Connect(m.c, args) + } + + if err != nil { + *pzErr = mPrintf("%s", err.Error()) + return 0 + } + vt := sqliteVTab{m, vTab} + *pzErr = nil + return C.uintptr_t(newHandle(m.c, &vt)) +} + +//export goVRelease +func goVRelease(pVTab unsafe.Pointer, isDestroy C.int) *C.char { + vt := lookupHandle(uintptr(pVTab)).(*sqliteVTab) + var err error + if isDestroy == 1 { + err = vt.vTab.Destroy() + } else { + err = vt.vTab.Disconnect() + } + if err != nil { + return mPrintf("%s", err.Error()) + } + return nil +} + +//export goVOpen +func goVOpen(pVTab unsafe.Pointer, pzErr **C.char) C.uintptr_t { + vt := lookupHandle(uintptr(pVTab)).(*sqliteVTab) + vTabCursor, err := vt.vTab.Open() + if err != nil { + *pzErr = mPrintf("%s", err.Error()) + return 0 + } + vtc := sqliteVTabCursor{vt, vTabCursor} + *pzErr = nil + return C.uintptr_t(newHandle(vt.module.c, &vtc)) +} + +//export goVBestIndex +func goVBestIndex(pVTab unsafe.Pointer, icp unsafe.Pointer) *C.char { + vt := lookupHandle(uintptr(pVTab)).(*sqliteVTab) + info := (*C.sqlite3_index_info)(icp) + csts := constraints(info) + res, err := vt.vTab.BestIndex(csts, orderBys(info)) + if err != nil { + return mPrintf("%s", err.Error()) + } + if len(res.Used) != len(csts) { + return mPrintf("Result.Used != expected value", "") + } + + // Get a pointer to constraint_usage struct so we can update in place. + l := info.nConstraint + s := (*[1 << 30]C.struct_sqlite3_index_constraint_usage)(unsafe.Pointer(info.aConstraintUsage))[:l:l] + index := 1 + for i := C.int(0); i < info.nConstraint; i++ { + if res.Used[i] { + s[i].argvIndex = C.int(index) + s[i].omit = C.uchar(1) + index++ + } + } + + info.idxNum = C.int(res.IdxNum) + idxStr := C.CString(res.IdxStr) + defer C.free(unsafe.Pointer(idxStr)) + info.idxStr = idxStr + info.needToFreeIdxStr = C.int(0) + if res.AlreadyOrdered { + info.orderByConsumed = C.int(1) + } + info.estimatedCost = C.double(res.EstimatedCost) + info.estimatedRows = C.sqlite3_int64(res.EstimatedRows) + + return nil +} + +//export goVClose +func goVClose(pCursor unsafe.Pointer) *C.char { + vtc := lookupHandle(uintptr(pCursor)).(*sqliteVTabCursor) + err := vtc.vTabCursor.Close() + if err != nil { + return mPrintf("%s", err.Error()) + } + return nil +} + +//export goMDestroy +func goMDestroy(pClientData unsafe.Pointer) { + m := lookupHandle(uintptr(pClientData)).(*sqliteModule) + m.module.DestroyModule() +} + +//export goVFilter +func goVFilter(pCursor unsafe.Pointer, idxNum C.int, idxName *C.char, argc C.int, argv **C.sqlite3_value) *C.char { + vtc := lookupHandle(uintptr(pCursor)).(*sqliteVTabCursor) + args := (*[(math.MaxInt32 - 1) / unsafe.Sizeof((*C.sqlite3_value)(nil))]*C.sqlite3_value)(unsafe.Pointer(argv))[:argc:argc] + vals := make([]interface{}, 0, argc) + for _, v := range args { + conv, err := callbackArgGeneric(v) + if err != nil { + return mPrintf("%s", err.Error()) + } + vals = append(vals, conv.Interface()) + } + err := vtc.vTabCursor.Filter(int(idxNum), C.GoString(idxName), vals) + if err != nil { + return mPrintf("%s", err.Error()) + } + return nil +} + +//export goVNext +func goVNext(pCursor unsafe.Pointer) *C.char { + vtc := lookupHandle(uintptr(pCursor)).(*sqliteVTabCursor) + err := vtc.vTabCursor.Next() + if err != nil { + return mPrintf("%s", err.Error()) + } + return nil +} + +//export goVEof +func goVEof(pCursor unsafe.Pointer) C.int { + vtc := lookupHandle(uintptr(pCursor)).(*sqliteVTabCursor) + err := vtc.vTabCursor.EOF() + if err { + return 1 + } + return 0 +} + +//export goVColumn +func goVColumn(pCursor, cp unsafe.Pointer, col C.int) *C.char { + vtc := lookupHandle(uintptr(pCursor)).(*sqliteVTabCursor) + c := (*SQLiteContext)(cp) + err := vtc.vTabCursor.Column(c, int(col)) + if err != nil { + return mPrintf("%s", err.Error()) + } + return nil +} + +//export goVRowid +func goVRowid(pCursor unsafe.Pointer, pRowid *C.sqlite3_int64) *C.char { + vtc := lookupHandle(uintptr(pCursor)).(*sqliteVTabCursor) + rowid, err := vtc.vTabCursor.Rowid() + if err != nil { + return mPrintf("%s", err.Error()) + } + *pRowid = C.sqlite3_int64(rowid) + return nil +} + +//export goVUpdate +func goVUpdate(pVTab unsafe.Pointer, argc C.int, argv **C.sqlite3_value, pRowid *C.sqlite3_int64) *C.char { + vt := lookupHandle(uintptr(pVTab)).(*sqliteVTab) + + var tname string + if n, ok := vt.vTab.(interface { + TableName() string + }); ok { + tname = n.TableName() + " " + } + + err := fmt.Errorf("virtual %s table %sis read-only", vt.module.name, tname) + if v, ok := vt.vTab.(VTabUpdater); ok { + // convert argv + args := (*[(math.MaxInt32 - 1) / unsafe.Sizeof((*C.sqlite3_value)(nil))]*C.sqlite3_value)(unsafe.Pointer(argv))[:argc:argc] + vals := make([]interface{}, 0, argc) + for _, v := range args { + conv, err := callbackArgGeneric(v) + if err != nil { + return mPrintf("%s", err.Error()) + } + + // work around for SQLITE_NULL + x := conv.Interface() + if z, ok := x.([]byte); ok && z == nil { + x = nil + } + + vals = append(vals, x) + } + + switch { + case argc == 1: + err = v.Delete(vals[0]) + + case argc > 1 && vals[0] == nil: + var id int64 + id, err = v.Insert(vals[1], vals[2:]) + if err == nil { + *pRowid = C.sqlite3_int64(id) + } + + case argc > 1: + err = v.Update(vals[1], vals[2:]) + } + } + + if err != nil { + return mPrintf("%s", err.Error()) + } + + return nil +} + +// Module is a "virtual table module", it defines the implementation of a +// virtual tables. See: http://sqlite.org/c3ref/module.html +type Module interface { + // http://sqlite.org/vtab.html#xcreate + Create(c *SQLiteConn, args []string) (VTab, error) + // http://sqlite.org/vtab.html#xconnect + Connect(c *SQLiteConn, args []string) (VTab, error) + // http://sqlite.org/c3ref/create_module.html + DestroyModule() +} + +// VTab describes a particular instance of the virtual table. +// See: http://sqlite.org/c3ref/vtab.html +type VTab interface { + // http://sqlite.org/vtab.html#xbestindex + BestIndex([]InfoConstraint, []InfoOrderBy) (*IndexResult, error) + // http://sqlite.org/vtab.html#xdisconnect + Disconnect() error + // http://sqlite.org/vtab.html#sqlite3_module.xDestroy + Destroy() error + // http://sqlite.org/vtab.html#xopen + Open() (VTabCursor, error) +} + +// VTabUpdater is a type that allows a VTab to be inserted, updated, or +// deleted. +// See: https://sqlite.org/vtab.html#xupdate +type VTabUpdater interface { + Delete(interface{}) error + Insert(interface{}, []interface{}) (int64, error) + Update(interface{}, []interface{}) error +} + +// VTabCursor describes cursors that point into the virtual table and are used +// to loop through the virtual table. See: http://sqlite.org/c3ref/vtab_cursor.html +type VTabCursor interface { + // http://sqlite.org/vtab.html#xclose + Close() error + // http://sqlite.org/vtab.html#xfilter + Filter(idxNum int, idxStr string, vals []interface{}) error + // http://sqlite.org/vtab.html#xnext + Next() error + // http://sqlite.org/vtab.html#xeof + EOF() bool + // http://sqlite.org/vtab.html#xcolumn + Column(c *SQLiteContext, col int) error + // http://sqlite.org/vtab.html#xrowid + Rowid() (int64, error) +} + +// DeclareVTab declares the Schema of a virtual table. +// See: http://sqlite.org/c3ref/declare_vtab.html +func (c *SQLiteConn) DeclareVTab(sql string) error { + zSQL := C.CString(sql) + defer C.free(unsafe.Pointer(zSQL)) + rv := C.sqlite3_declare_vtab(c.db, zSQL) + if rv != C.SQLITE_OK { + return c.lastError() + } + return nil +} + +// CreateModule registers a virtual table implementation. +// See: http://sqlite.org/c3ref/create_module.html +func (c *SQLiteConn) CreateModule(moduleName string, module Module) error { + mname := C.CString(moduleName) + defer C.free(unsafe.Pointer(mname)) + udm := sqliteModule{c, moduleName, module} + rv := C._sqlite3_create_module(c.db, mname, C.uintptr_t(newHandle(c, &udm))) + if rv != C.SQLITE_OK { + return c.lastError() + } + return nil +} |