summaryrefslogtreecommitdiffstats
path: root/vendor/github.com/go-sql-driver/mysql/connection.go
blob: e57061412bc2d12afb4fc073e89fab41158cdb52 (plain)
1
2
3
4
5
6
7
8
9
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
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
// Go MySQL Driver - A MySQL-Driver for Go's database/sql package
//
// Copyright 2012 The Go-MySQL-Driver Authors. All rights reserved.
//
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this file,
// You can obtain one at http://mozilla.org/MPL/2.0/.

package mysql

import (
	"database/sql/driver"
	"io"
	"net"
	"strconv"
	"strings"
	"time"
)

// a copy of context.Context for Go 1.7 and earlier
type mysqlContext interface {
	Done() <-chan struct{}
	Err() error

	// defined in context.Context, but not used in this driver:
	// Deadline() (deadline time.Time, ok bool)
	// Value(key interface{}) interface{}
}

type mysqlConn struct {
	buf              buffer
	netConn          net.Conn
	affectedRows     uint64
	insertId         uint64
	cfg              *Config
	maxAllowedPacket int
	maxWriteSize     int
	writeTimeout     time.Duration
	flags            clientFlag
	status           statusFlag
	sequence         uint8
	parseTime        bool

	// for context support (Go 1.8+)
	watching bool
	watcher  chan<- mysqlContext
	closech  chan struct{}
	finished chan<- struct{}
	canceled atomicError // set non-nil if conn is canceled
	closed   atomicBool  // set when conn is closed, before closech is closed
}

// Handles parameters set in DSN after the connection is established
func (mc *mysqlConn) handleParams() (err error) {
	for param, val := range mc.cfg.Params {
		switch param {
		// Charset
		case "charset":
			charsets := strings.Split(val, ",")
			for i := range charsets {
				// ignore errors here - a charset may not exist
				err = mc.exec("SET NAMES " + charsets[i])
				if err == nil {
					break
				}
			}
			if err != nil {
				return
			}

		// System Vars
		default:
			err = mc.exec("SET " + param + "=" + val + "")
			if err != nil {
				return
			}
		}
	}

	return
}

func (mc *mysqlConn) markBadConn(err error) error {
	if mc == nil {
		return err
	}
	if err != errBadConnNoWrite {
		return err
	}
	return driver.ErrBadConn
}

func (mc *mysqlConn) Begin() (driver.Tx, error) {
	return mc.begin(false)
}

func (mc *mysqlConn) begin(readOnly bool) (driver.Tx, error) {
	if mc.closed.IsSet() {
		errLog.Print(ErrInvalidConn)
		return nil, driver.ErrBadConn
	}
	var q string
	if readOnly {
		q = "START TRANSACTION READ ONLY"
	} else {
		q = "START TRANSACTION"
	}
	err := mc.exec(q)
	if err == nil {
		return &mysqlTx{mc}, err
	}
	return nil, mc.markBadConn(err)
}

func (mc *mysqlConn) Close() (err error) {
	// Makes Close idempotent
	if !mc.closed.IsSet() {
		err = mc.writeCommandPacket(comQuit)
	}

	mc.cleanup()

	return
}

// Closes the network connection and unsets internal variables. Do not call this
// function after successfully authentication, call Close instead. This function
// is called before auth or on auth failure because MySQL will have already
// closed the network connection.
func (mc *mysqlConn) cleanup() {
	if !mc.closed.TrySet(true) {
		return
	}

	// Makes cleanup idempotent
	close(mc.closech)
	if mc.netConn == nil {
		return
	}
	if err := mc.netConn.Close(); err != nil {
		errLog.Print(err)
	}
}

func (mc *mysqlConn) error() error {
	if mc.closed.IsSet() {
		if err := mc.canceled.Value(); err != nil {
			return err
		}
		return ErrInvalidConn
	}
	return nil
}

func (mc *mysqlConn) Prepare(query string) (driver.Stmt, error) {
	if mc.closed.IsSet() {
		errLog.Print(ErrInvalidConn)
		return nil, driver.ErrBadConn
	}
	// Send command
	err := mc.writeCommandPacketStr(comStmtPrepare, query)
	if err != nil {
		return nil, mc.markBadConn(err)
	}

	stmt := &mysqlStmt{
		mc: mc,
	}

	// Read Result
	columnCount, err := stmt.readPrepareResultPacket()
	if err == nil {
		if stmt.paramCount > 0 {
			if err = mc.readUntilEOF(); err != nil {
				return nil, err
			}
		}

		if columnCount > 0 {
			err = mc.readUntilEOF()
		}
	}

	return stmt, err
}

func (mc *mysqlConn) interpolateParams(query string, args []driver.Value) (string, error) {
	// Number of ? should be same to len(args)
	if strings.Count(query, "?") != len(args) {
		return "", driver.ErrSkip
	}

	buf := mc.buf.takeCompleteBuffer()
	if buf == nil {
		// can not take the buffer. Something must be wrong with the connection
		errLog.Print(ErrBusyBuffer)
		return "", ErrInvalidConn
	}
	buf = buf[:0]
	argPos := 0

	for i := 0; i < len(query); i++ {
		q := strings.IndexByte(query[i:], '?')
		if q == -1 {
			buf = append(buf, query[i:]...)
			break
		}
		buf = append(buf, query[i:i+q]...)
		i += q

		arg := args[argPos]
		argPos++

		if arg == nil {
			buf = append(buf, "NULL"...)
			continue
		}

		switch v := arg.(type) {
		case int64:
			buf = strconv.AppendInt(buf, v, 10)
		case float64:
			buf = strconv.AppendFloat(buf, v, 'g', -1, 64)
		case bool:
			if v {
				buf = append(buf, '1')
			} else {
				buf = append(buf, '0')
			}
		case time.Time:
			if v.IsZero() {
				buf = append(buf, "'0000-00-00'"...)
			} else {
				v := v.In(mc.cfg.Loc)
				v = v.Add(time.Nanosecond * 500) // To round under microsecond
				year := v.Year()
				year100 := year / 100
				year1 := year % 100
				month := v.Month()
				day := v.Day()
				hour := v.Hour()
				minute := v.Minute()
				second := v.Second()
				micro := v.Nanosecond() / 1000

				buf = append(buf, []byte{
					'\'',
					digits10[year100], digits01[year100],
					digits10[year1], digits01[year1],
					'-',
					digits10[month], digits01[month],
					'-',
					digits10[day], digits01[day],
					' ',
					digits10[hour], digits01[hour],
					':',
					digits10[minute], digits01[minute],
					':',
					digits10[second], digits01[second],
				}...)

				if micro != 0 {
					micro10000 := micro / 10000
					micro100 := micro / 100 % 100
					micro1 := micro % 100
					buf = append(buf, []byte{
						'.',
						digits10[micro10000], digits01[micro10000],
						digits10[micro100], digits01[micro100],
						digits10[micro1], digits01[micro1],
					}...)
				}
				buf = append(buf, '\'')
			}
		case []byte:
			if v == nil {
				buf = append(buf, "NULL"...)
			} else {
				buf = append(buf, "_binary'"...)
				if mc.status&statusNoBackslashEscapes == 0 {
					buf = escapeBytesBackslash(buf, v)
				} else {
					buf = escapeBytesQuotes(buf, v)
				}
				buf = append(buf, '\'')
			}
		case string:
			buf = append(buf, '\'')
			if mc.status&statusNoBackslashEscapes == 0 {
				buf = escapeStringBackslash(buf, v)
			} else {
				buf = escapeStringQuotes(buf, v)
			}
			buf = append(buf, '\'')
		default:
			return "", driver.ErrSkip
		}

		if len(buf)+4 > mc.maxAllowedPacket {
			return "", driver.ErrSkip
		}
	}
	if argPos != len(args) {
		return "", driver.ErrSkip
	}
	return string(buf), nil
}

func (mc *mysqlConn) Exec(query string, args []driver.Value) (driver.Result, error) {
	if mc.closed.IsSet() {
		errLog.Print(ErrInvalidConn)
		return nil, driver.ErrBadConn
	}
	if len(args) != 0 {
		if !mc.cfg.InterpolateParams {
			return nil, driver.ErrSkip
		}
		// try to interpolate the parameters to save extra roundtrips for preparing and closing a statement
		prepared, err := mc.interpolateParams(query, args)
		if err != nil {
			return nil, err
		}
		query = prepared
	}
	mc.affectedRows = 0
	mc.insertId = 0

	err := mc.exec(query)
	if err == nil {
		return &mysqlResult{
			affectedRows: int64(mc.affectedRows),
			insertId:     int64(mc.insertId),
		}, err
	}
	return nil, mc.markBadConn(err)
}

// Internal function to execute commands
func (mc *mysqlConn) exec(query string) error {
	// Send command
	if err := mc.writeCommandPacketStr(comQuery, query); err != nil {
		return mc.markBadConn(err)
	}

	// Read Result
	resLen, err := mc.readResultSetHeaderPacket()
	if err != nil {
		return err
	}

	if resLen > 0 {
		// columns
		if err := mc.readUntilEOF(); err != nil {
			return err
		}

		// rows
		if err := mc.readUntilEOF(); err != nil {
			return err
		}
	}

	return mc.discardResults()
}

func (mc *mysqlConn) Query(query string, args []driver.Value) (driver.Rows, error) {
	return mc.query(query, args)
}

func (mc *mysqlConn) query(query string, args []driver.Value) (*textRows, error) {
	if mc.closed.IsSet() {
		errLog.Print(ErrInvalidConn)
		return nil, driver.ErrBadConn
	}
	if len(args) != 0 {
		if !mc.cfg.InterpolateParams {
			return nil, driver.ErrSkip
		}
		// try client-side prepare to reduce roundtrip
		prepared, err := mc.interpolateParams(query, args)
		if err != nil {
			return nil, err
		}
		query = prepared
	}
	// Send command
	err := mc.writeCommandPacketStr(comQuery, query)
	if err == nil {
		// Read Result
		var resLen int
		resLen, err = mc.readResultSetHeaderPacket()
		if err == nil {
			rows := new(textRows)
			rows.mc = mc

			if resLen == 0 {
				rows.rs.done = true

				switch err := rows.NextResultSet(); err {
				case nil, io.EOF:
					return rows, nil
				default:
					return nil, err
				}
			}

			// Columns
			rows.rs.columns, err = mc.readColumns(resLen)
			return rows, err
		}
	}
	return nil, mc.markBadConn(err)
}

// Gets the value of the given MySQL System Variable
// The returned byte slice is only valid until the next read
func (mc *mysqlConn) getSystemVar(name string) ([]byte, error) {
	// Send command
	if err := mc.writeCommandPacketStr(comQuery, "SELECT @@"+name); err != nil {
		return nil, err
	}

	// Read Result
	resLen, err := mc.readResultSetHeaderPacket()
	if err == nil {
		rows := new(textRows)
		rows.mc = mc
		rows.rs.columns = []mysqlField{{fieldType: fieldTypeVarChar}}

		if resLen > 0 {
			// Columns
			if err := mc.readUntilEOF(); err != nil {
				return nil, err
			}
		}

		dest := make([]driver.Value, resLen)
		if err = rows.readRow(dest); err == nil {
			return dest[0].([]byte), mc.readUntilEOF()
		}
	}
	return nil, err
}

// finish is called when the query has canceled.
func (mc *mysqlConn) cancel(err error) {
	mc.canceled.Set(err)
	mc.cleanup()
}

// finish is called when the query has succeeded.
func (mc *mysqlConn) finish() {
	if !mc.watching || mc.finished == nil {
		return
	}
	select {
	case mc.finished <- struct{}{}:
		mc.watching = false
	case <-mc.closech:
	}
}