From baf7141d1dd0f99d561a2197a909c66dd389809d Mon Sep 17 00:00:00 2001 From: Niall Sheridan Date: Sat, 8 Oct 2016 16:02:50 -0500 Subject: Update dependencies --- .../github.com/mattn/go-sqlite3/tracecallback.go | 415 +++++++++++++++++++++ 1 file changed, 415 insertions(+) create mode 100644 vendor/github.com/mattn/go-sqlite3/tracecallback.go (limited to 'vendor/github.com/mattn/go-sqlite3/tracecallback.go') diff --git a/vendor/github.com/mattn/go-sqlite3/tracecallback.go b/vendor/github.com/mattn/go-sqlite3/tracecallback.go new file mode 100644 index 0000000..bf222b5 --- /dev/null +++ b/vendor/github.com/mattn/go-sqlite3/tracecallback.go @@ -0,0 +1,415 @@ +// Copyright (C) 2016 Yasuhiro Matsumoto . +// TODO: add "Gimpl do foo" team? +// +// Use of this source code is governed by an MIT-style +// license that can be found in the LICENSE file. +// +build trace + +package sqlite3 + +/* +#ifndef USE_LIBSQLITE3 +#include +#else +#include +#endif +#include + +void stepTrampoline(sqlite3_context*, int, sqlite3_value**); +void doneTrampoline(sqlite3_context*); +void traceCallbackTrampoline(unsigned traceEventCode, void *ctx, void *p, void *x); +*/ +import "C" + +import ( + "errors" + "fmt" + "reflect" + "strings" + "sync" + "unsafe" +) + +// Trace... constants identify the possible events causing callback invocation. +// Values are same as the corresponding SQLite Trace Event Codes. +const ( + TraceStmt = C.SQLITE_TRACE_STMT + TraceProfile = C.SQLITE_TRACE_PROFILE + TraceRow = C.SQLITE_TRACE_ROW + TraceClose = C.SQLITE_TRACE_CLOSE +) + +type TraceInfo struct { + // Pack together the shorter fields, to keep the struct smaller. + // On a 64-bit machine there would be padding + // between EventCode and ConnHandle; having AutoCommit here is "free": + EventCode uint32 + AutoCommit bool + ConnHandle uintptr + + // Usually filled, unless EventCode = TraceClose = SQLITE_TRACE_CLOSE: + // identifier for a prepared statement: + StmtHandle uintptr + + // Two strings filled when EventCode = TraceStmt = SQLITE_TRACE_STMT: + // (1) either the unexpanded SQL text of the prepared statement, or + // an SQL comment that indicates the invocation of a trigger; + // (2) expanded SQL, if requested and if (1) is not an SQL comment. + StmtOrTrigger string + ExpandedSQL string // only if requested (TraceConfig.WantExpandedSQL = true) + + // filled when EventCode = TraceProfile = SQLITE_TRACE_PROFILE: + // estimated number of nanoseconds that the prepared statement took to run: + RunTimeNanosec int64 + + DBError Error +} + +// TraceUserCallback gives the signature for a trace function +// provided by the user (Go application programmer). +// SQLite 3.14 documentation (as of September 2, 2016) +// for SQL Trace Hook = sqlite3_trace_v2(): +// The integer return value from the callback is currently ignored, +// though this may change in future releases. Callback implementations +// should return zero to ensure future compatibility. +type TraceUserCallback func(TraceInfo) int + +type TraceConfig struct { + Callback TraceUserCallback + EventMask uint + WantExpandedSQL bool +} + +func fillDBError(dbErr *Error, db *C.sqlite3) { + // See SQLiteConn.lastError(), in file 'sqlite3.go' at the time of writing (Sept 5, 2016) + dbErr.Code = ErrNo(C.sqlite3_errcode(db)) + dbErr.ExtendedCode = ErrNoExtended(C.sqlite3_extended_errcode(db)) + dbErr.err = C.GoString(C.sqlite3_errmsg(db)) +} + +func fillExpandedSQL(info *TraceInfo, db *C.sqlite3, pStmt unsafe.Pointer) { + if pStmt == nil { + panic("No SQLite statement pointer in P arg of trace_v2 callback") + } + + expSQLiteCStr := C.sqlite3_expanded_sql((*C.sqlite3_stmt)(pStmt)) + if expSQLiteCStr == nil { + fillDBError(&info.DBError, db) + return + } + info.ExpandedSQL = C.GoString(expSQLiteCStr) +} + +//export traceCallbackTrampoline +func traceCallbackTrampoline( + traceEventCode uint, + // Parameter named 'C' in SQLite docs = Context given at registration: + ctx unsafe.Pointer, + // Parameter named 'P' in SQLite docs (Primary event data?): + p unsafe.Pointer, + // Parameter named 'X' in SQLite docs (eXtra event data?): + xValue unsafe.Pointer) int { + + if ctx == nil { + panic(fmt.Sprintf("No context (ev 0x%x)", traceEventCode)) + } + + contextDB := (*C.sqlite3)(ctx) + connHandle := uintptr(ctx) + + var traceConf TraceConfig + var found bool + if traceEventCode == TraceClose { + // clean up traceMap: 'pop' means get and delete + traceConf, found = popTraceMapping(connHandle) + } else { + traceConf, found = lookupTraceMapping(connHandle) + } + + if !found { + panic(fmt.Sprintf("Mapping not found for handle 0x%x (ev 0x%x)", + connHandle, traceEventCode)) + } + + var info TraceInfo + + info.EventCode = uint32(traceEventCode) + info.AutoCommit = (int(C.sqlite3_get_autocommit(contextDB)) != 0) + info.ConnHandle = connHandle + + switch traceEventCode { + case TraceStmt: + info.StmtHandle = uintptr(p) + + var xStr string + if xValue != nil { + xStr = C.GoString((*C.char)(xValue)) + } + info.StmtOrTrigger = xStr + if !strings.HasPrefix(xStr, "--") { + // Not SQL comment, therefore the current event + // is not related to a trigger. + // The user might want to receive the expanded SQL; + // let's check: + if traceConf.WantExpandedSQL { + fillExpandedSQL(&info, contextDB, p) + } + } + + case TraceProfile: + info.StmtHandle = uintptr(p) + + if xValue == nil { + panic("NULL pointer in X arg of trace_v2 callback for SQLITE_TRACE_PROFILE event") + } + + info.RunTimeNanosec = *(*int64)(xValue) + + // sample the error //TODO: is it safe? is it useful? + fillDBError(&info.DBError, contextDB) + + case TraceRow: + info.StmtHandle = uintptr(p) + + case TraceClose: + handle := uintptr(p) + if handle != info.ConnHandle { + panic(fmt.Sprintf("Different conn handle 0x%x (expected 0x%x) in SQLITE_TRACE_CLOSE event.", + handle, info.ConnHandle)) + } + + default: + // Pass unsupported events to the user callback (if configured); + // let the user callback decide whether to panic or ignore them. + } + + // Do not execute user callback when the event was not requested by user! + // Remember that the Close event is always selected when + // registering this callback trampoline with SQLite --- for cleanup. + // In the future there may be more events forced to "selected" in SQLite + // for the driver's needs. + if traceConf.EventMask&traceEventCode == 0 { + return 0 + } + + r := 0 + if traceConf.Callback != nil { + r = traceConf.Callback(info) + } + return r +} + +type traceMapEntry struct { + config TraceConfig +} + +var traceMapLock sync.Mutex +var traceMap = make(map[uintptr]traceMapEntry) + +func addTraceMapping(connHandle uintptr, traceConf TraceConfig) { + traceMapLock.Lock() + defer traceMapLock.Unlock() + + oldEntryCopy, found := traceMap[connHandle] + if found { + panic(fmt.Sprintf("Adding trace config %v: handle 0x%x already registered (%v).", + traceConf, connHandle, oldEntryCopy.config)) + } + traceMap[connHandle] = traceMapEntry{config: traceConf} + fmt.Printf("Added trace config %v: handle 0x%x.\n", traceConf, connHandle) +} + +func lookupTraceMapping(connHandle uintptr) (TraceConfig, bool) { + traceMapLock.Lock() + defer traceMapLock.Unlock() + + entryCopy, found := traceMap[connHandle] + return entryCopy.config, found +} + +// 'pop' = get and delete from map before returning the value to the caller +func popTraceMapping(connHandle uintptr) (TraceConfig, bool) { + traceMapLock.Lock() + defer traceMapLock.Unlock() + + entryCopy, found := traceMap[connHandle] + if found { + delete(traceMap, connHandle) + fmt.Printf("Pop handle 0x%x: deleted trace config %v.\n", connHandle, entryCopy.config) + } + return entryCopy.config, found +} + +// RegisterAggregator makes a Go type available as a SQLite aggregation function. +// +// Because aggregation is incremental, it's implemented in Go with a +// type that has 2 methods: func Step(values) accumulates one row of +// data into the accumulator, and func Done() ret finalizes and +// returns the aggregate value. "values" and "ret" may be any type +// supported by RegisterFunc. +// +// RegisterAggregator takes as implementation a constructor function +// that constructs an instance of the aggregator type each time an +// aggregation begins. The constructor must return a pointer to a +// type, or an interface that implements Step() and Done(). +// +// The constructor function and the Step/Done methods may optionally +// return an error in addition to their other return values. +// +// See _example/go_custom_funcs for a detailed example. +func (c *SQLiteConn) RegisterAggregator(name string, impl interface{}, pure bool) error { + var ai aggInfo + ai.constructor = reflect.ValueOf(impl) + t := ai.constructor.Type() + if t.Kind() != reflect.Func { + return errors.New("non-function passed to RegisterAggregator") + } + if t.NumOut() != 1 && t.NumOut() != 2 { + return errors.New("SQLite aggregator constructors must return 1 or 2 values") + } + if t.NumOut() == 2 && !t.Out(1).Implements(reflect.TypeOf((*error)(nil)).Elem()) { + return errors.New("Second return value of SQLite function must be error") + } + if t.NumIn() != 0 { + return errors.New("SQLite aggregator constructors must not have arguments") + } + + agg := t.Out(0) + switch agg.Kind() { + case reflect.Ptr, reflect.Interface: + default: + return errors.New("SQlite aggregator constructor must return a pointer object") + } + stepFn, found := agg.MethodByName("Step") + if !found { + return errors.New("SQlite aggregator doesn't have a Step() function") + } + step := stepFn.Type + if step.NumOut() != 0 && step.NumOut() != 1 { + return errors.New("SQlite aggregator Step() function must return 0 or 1 values") + } + if step.NumOut() == 1 && !step.Out(0).Implements(reflect.TypeOf((*error)(nil)).Elem()) { + return errors.New("type of SQlite aggregator Step() return value must be error") + } + + stepNArgs := step.NumIn() + start := 0 + if agg.Kind() == reflect.Ptr { + // Skip over the method receiver + stepNArgs-- + start++ + } + if step.IsVariadic() { + stepNArgs-- + } + for i := start; i < start+stepNArgs; i++ { + conv, err := callbackArg(step.In(i)) + if err != nil { + return err + } + ai.stepArgConverters = append(ai.stepArgConverters, conv) + } + if step.IsVariadic() { + conv, err := callbackArg(t.In(start + stepNArgs).Elem()) + if err != nil { + return err + } + ai.stepVariadicConverter = conv + // Pass -1 to sqlite so that it allows any number of + // arguments. The call helper verifies that the minimum number + // of arguments is present for variadic functions. + stepNArgs = -1 + } + + doneFn, found := agg.MethodByName("Done") + if !found { + return errors.New("SQlite aggregator doesn't have a Done() function") + } + done := doneFn.Type + doneNArgs := done.NumIn() + if agg.Kind() == reflect.Ptr { + // Skip over the method receiver + doneNArgs-- + } + if doneNArgs != 0 { + return errors.New("SQlite aggregator Done() function must have no arguments") + } + if done.NumOut() != 1 && done.NumOut() != 2 { + return errors.New("SQLite aggregator Done() function must return 1 or 2 values") + } + if done.NumOut() == 2 && !done.Out(1).Implements(reflect.TypeOf((*error)(nil)).Elem()) { + return errors.New("second return value of SQLite aggregator Done() function must be error") + } + + conv, err := callbackRet(done.Out(0)) + if err != nil { + return err + } + ai.doneRetConverter = conv + ai.active = make(map[int64]reflect.Value) + ai.next = 1 + + // ai must outlast the database connection, or we'll have dangling pointers. + c.aggregators = append(c.aggregators, &ai) + + cname := C.CString(name) + defer C.free(unsafe.Pointer(cname)) + opts := C.SQLITE_UTF8 + if pure { + opts |= C.SQLITE_DETERMINISTIC + } + rv := C._sqlite3_create_function(c.db, cname, C.int(stepNArgs), C.int(opts), C.uintptr_t(newHandle(c, &ai)), nil, (*[0]byte)(unsafe.Pointer(C.stepTrampoline)), (*[0]byte)(unsafe.Pointer(C.doneTrampoline))) + if rv != C.SQLITE_OK { + return c.lastError() + } + return nil +} + +// SetTrace installs or removes the trace callback for the given database connection. +// It's not named 'RegisterTrace' because only one callback can be kept and called. +// Calling SetTrace a second time on same database connection +// overrides (cancels) any prior callback and all its settings: +// event mask, etc. +func (c *SQLiteConn) SetTrace(requested *TraceConfig) error { + connHandle := uintptr(unsafe.Pointer(c.db)) + + _, _ = popTraceMapping(connHandle) + + if requested == nil { + // The traceMap entry was deleted already by popTraceMapping(): + // can disable all events now, no need to watch for TraceClose. + err := c.setSQLiteTrace(0) + return err + } + + reqCopy := *requested + + // Disable potentially expensive operations + // if their result will not be used. We are doing this + // just in case the caller provided nonsensical input. + if reqCopy.EventMask&TraceStmt == 0 { + reqCopy.WantExpandedSQL = false + } + + addTraceMapping(connHandle, reqCopy) + + // The callback trampoline function does cleanup on Close event, + // regardless of the presence or absence of the user callback. + // Therefore it needs the Close event to be selected: + actualEventMask := reqCopy.EventMask | TraceClose + err := c.setSQLiteTrace(actualEventMask) + return err +} + +func (c *SQLiteConn) setSQLiteTrace(sqliteEventMask uint) error { + rv := C.sqlite3_trace_v2(c.db, + C.uint(sqliteEventMask), + (*[0]byte)(unsafe.Pointer(C.traceCallbackTrampoline)), + unsafe.Pointer(c.db)) // Fourth arg is same as first: we are + // passing the database connection handle as callback context. + + if rv != C.SQLITE_OK { + return c.lastError() + } + return nil +} -- cgit v1.2.3