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authorNiall Sheridan <nsheridan@gmail.com>2017-04-10 21:18:42 +0100
committerNiall Sheridan <nsheridan@gmail.com>2017-04-10 21:38:33 +0100
commit30802e07b2d84fbc213b490d3402707dffe60096 (patch)
tree934aecb8f3582325dfd1aa6652193adac87d00db /vendor/github.com/mattn/go-sqlite3/tracecallback.go
parentda7638dc112c4c106e8929601b642d2ca4596cba (diff)
update dependencies
Diffstat (limited to 'vendor/github.com/mattn/go-sqlite3/tracecallback.go')
-rw-r--r--vendor/github.com/mattn/go-sqlite3/tracecallback.go414
1 files changed, 0 insertions, 414 deletions
diff --git a/vendor/github.com/mattn/go-sqlite3/tracecallback.go b/vendor/github.com/mattn/go-sqlite3/tracecallback.go
deleted file mode 100644
index de1d504..0000000
--- a/vendor/github.com/mattn/go-sqlite3/tracecallback.go
+++ /dev/null
@@ -1,414 +0,0 @@
-// Copyright (C) 2016 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 trace
-
-package sqlite3
-
-/*
-#ifndef USE_LIBSQLITE3
-#include <sqlite3-binding.h>
-#else
-#include <sqlite3.h>
-#endif
-#include <stdlib.h>
-
-void stepTrampoline(sqlite3_context*, int, sqlite3_value**);
-void doneTrampoline(sqlite3_context*);
-int traceCallbackTrampoline(unsigned int 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 C.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 C.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) C.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 C.int(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 := sqlite3_create_function(c.db, cname, C.int(stepNArgs), C.int(opts), newHandle(c, &ai), nil, C.stepTrampoline, 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 := uint(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
-}