Example #1
0
// Samples 'k' unique ints from the range [0, n)
func SampleInts(n int, k int) (res []int, err error) {
	if k < 0 {
		err = errors.Newf("invalid sample size k")
		return
	}

	if n < k {
		err = errors.Newf("sample size k larger than n")
		return
	}

	picked := set.NewSet()
	for picked.Len() < k {
		i := Intn(n)
		picked.Add(i)
	}

	res = make([]int, k)
	e := 0
	for i := range picked.Iter() {
		res[e] = i.(int)
		e++
	}

	return
}
Example #2
0
func serializeClauses(
	clauses []Clause,
	separator []byte,
	out *bytes.Buffer) (err error) {

	if clauses == nil || len(clauses) == 0 {
		return errors.Newf("Empty clauses.  Generated sql: %s", out.String())
	}

	if clauses[0] == nil {
		return errors.Newf("nil clause.  Generated sql: %s", out.String())
	}
	if err = clauses[0].SerializeSql(out); err != nil {
		return
	}

	for _, c := range clauses[1:] {
		out.Write(separator)

		if c == nil {
			return errors.Newf("nil clause.  Generated sql: %s", out.String())
		}
		if err = c.SerializeSql(out); err != nil {
			return
		}
	}

	return nil
}
Example #3
0
func (c *aliasColumn) SerializeSqlForColumnList(includeTableName bool, database Database, out *bytes.Buffer) error {
	if !validIdentifierName(c.name) {
		return errors.Newf(
			"Invalid alias name `%s`.  Generated sql: %s",
			c.name,
			out.String())
	}
	if c.expression == nil {
		return errors.Newf(
			"Cannot alias a nil expression.  Generated sql: %s",
			out.String())
	}

	out.WriteByte('(')
	if c.expression == nil {
		return errors.Newf("nil alias clause.  Generate sql: %s", out.String())
	}
	if err := c.expression.SerializeSql(database, out); err != nil {
		return err
	}
	out.WriteString(") AS ")
	out.WriteRune(database.EscapeCharacter())
	out.WriteString(c.name)
	out.WriteRune(database.EscapeCharacter())
	return nil
}
Example #4
0
func (c *aliasColumn) SerializeSqlForColumnList(out *bytes.Buffer) error {
	if !validIdentifierName(c.name) {
		return errors.Newf(
			"Invalid alias name `%s`.  Generated sql: %s",
			c.name,
			out.String())
	}
	if c.expression == nil {
		return errors.Newf(
			"Cannot alias a nil expression.  Generated sql: %s",
			out.String())
	}

	out.WriteByte('(')
	if c.expression == nil {
		return errors.Newf("nil alias clause.  Generate sql: %s", out.String())
	}
	if err := c.expression.SerializeSql(out); err != nil {
		return err
	}
	out.WriteString(") AS `")
	out.WriteString(c.name)
	out.WriteByte('`')
	return nil
}
Example #5
0
func (p *baseRowsEventParser) parseRowsHeader(raw *RawV4Event) (
	id uint64,
	flags uint16,
	extraInfo []byte,
	width int,
	remaining []byte,
	err error) {

	if p.context == nil {
		return 0, 0, nil, 0, nil, &TableContextNotSetError{
			errors.New("Table context not set"),
		}
	}

	data := raw.FixedLengthData()

	id = LittleEndian.Uint48(data)

	if id != p.context.TableId() {
		return 0, 0, nil, 0, nil, errors.Newf(
			"mismatch table id (event: %d; context: %d name: %s)",
			id,
			p.context.TableId(),
			p.context.TableName())
	}

	flags = LittleEndian.Uint16(data[6:])

	remaining = raw.VariableLengthData()

	if p.version == mysql_proto.RowsEventVersion_V1 {
		extraInfo = nil
	} else {
		extraInfoBlobLen := LittleEndian.Uint16(data[8:])
		extraInfo, remaining, err = p.parseExtraInfoBlob(
			extraInfoBlobLen,
			remaining)
		if err != nil {
			return 0, 0, nil, 0, nil, err
		}
	}

	w, remaining, err := readFieldLength(remaining)
	if err != nil {
		return 0, 0, nil, 0, nil, err
	}

	if w > uint64(p.context.NumColumns()) {
		return 0, 0, nil, 0, nil, errors.Newf(
			"row width (%d / %d) greater than # of columns (%d) in table %s",
			w,
			width,
			p.context.NumColumns(),
			string(p.context.TableName()))
	}

	return id, flags, extraInfo, int(w), remaining, nil
}
Example #6
0
func (s *Source) validate() (err error) {
	if strings.ToLower(s.Hash) == "skip" {
		return
	}

	file, err := os.Open(s.Path)
	if err != nil {
		err = &HashError{
			errors.Wrap(err, "source: Failed to open file for hash"),
		}
		return
	}
	defer file.Close()

	var hash hash.Hash
	switch len(s.Hash) {
	case 32:
		hash = md5.New()
	case 40:
		hash = sha1.New()
	case 64:
		hash = sha256.New()
	case 128:
		hash = sha512.New()
	default:
		err = &HashError{
			errors.Newf("source: Unknown hash type for hash '%s'", s.Hash),
		}
		return
	}

	_, err = io.Copy(hash, file)
	if err != nil {
		return
	}

	sum := hash.Sum([]byte{})

	hexSum := fmt.Sprintf("%x", sum)

	if hexSum != s.Hash {
		err = &HashError{
			errors.Newf("source: Hash verification failed for '%s'", s.Source),
		}
		return
	}

	return
}
// See ResourcePool for documentation.
func (p *MultiResourcePool) Register(resourceLocation string) error {
	if resourceLocation == "" {
		return errors.New("Registering invalid resource location")
	}

	p.rwMutex.Lock()
	defer p.rwMutex.Unlock()

	if p.isLameDuck {
		return errors.Newf(
			"Cannot register %s to lame duck resource pool",
			resourceLocation)
	}

	if _, inMap := p.locationPools[resourceLocation]; inMap {
		return nil
	}

	pool := p.createPool(p.options)
	if err := pool.Register(resourceLocation); err != nil {
		return err
	}

	p.locationPools[resourceLocation] = pool
	return nil
}
Example #8
0
// Writes an image to a file. The extension of the file is used to determine the
// encoding method.
func CreateImage(i image.Image, file string) error {
	ext := filepath.Ext(file)
	m := mime.TypeByExtension(ext)

	switch m {
	case "image/jpeg", "image/png", "image/tiff":
	default:
		return errors.Newf("unsupported extension/mime type: %s %s", ext, m)
	}

	f, err := os.Create(file)
	if err != nil {
		return errors.Wrap(err, "could not create file")
	}
	defer f.Close()

	switch m {
	case "image/jpeg":
		err = jpeg.Encode(f, i, &jpeg.Options{Quality: 98})
	case "image/png":
		err = png.Encode(f, i)
	case "image/tiff":
		err = tiff.Encode(f, i, &tiff.Options{Compression: tiff.Deflate, Predictor: true})
	default:
		panic("unreachable")
	}
	if err != nil {
		return errors.Wrap(err, "could not encode image")
	}

	return nil
}
// Peek returns a slice of the look ahead buffer which holds numBytes
// number of bytes.  If the look ahead buffer does not already hold enough
// bytes, it will read from the underlying reader to populate the rest.
// NOTE: the returned slice is not a copy of the raw buffer.
func (b *LookAheadBuffer) Peek(numBytes int) ([]byte, error) {
	if numBytes < 0 {
		return nil, errors.New("Cannot fill negative numBytes")
	}
	if numBytes > len(b.buffer) {
		return nil, errors.Newf(
			"Buffer full (buffer size: %d n: %d)",
			len(b.buffer),
			numBytes)
	}

	var err error
	var numRead int
	if b.bytesBuffered < numBytes {
		numRead, err = io.ReadAtLeast(
			b.src,
			b.buffer[b.bytesBuffered:],
			numBytes-b.bytesBuffered)
		if err != nil {
			if err == io.ErrUnexpectedEOF {
				// ErrUnexpectedEOF is a terrible error only returned by
				// ReadAtLeast.  Return EOF (i.e., the original error) instead
				// ErrUnexpectedEOF since no one ever checks for this.
				err = io.EOF
			}
		}
	}

	b.bytesBuffered += numRead

	if numBytes > b.bytesBuffered {
		numBytes = b.bytesBuffered
	}
	return b.buffer[:numBytes], err
}
// See ConnectionPool for documentation.
func (p *MultiConnectionPool) Register(network string, address string) error {
	if network == "" && address == "" {
		return errors.New("Registering invalid (network, address)")
	}

	key := NetworkAddress{
		Network: network,
		Address: address,
	}

	p.rwMutex.Lock()
	defer p.rwMutex.Unlock()

	if p.isLameDuck {
		return errors.Newf(
			"Cannot register (%s, %s) to lame duck connection pool",
			network,
			address)
	}

	if _, inMap := p.addressPools[key]; inMap {
		return nil
	}

	pool := p.createPool(p.options)
	if err := pool.Register(network, address); err != nil {
		return err
	}

	p.addressPools[key] = pool
	return nil
}
Example #11
0
func GetPacker(pac *pack.Pack, distro, release string) (
	pcker Packer, err error) {

	switch constants.DistroPack[distro] {
	case "pacman":
		pcker = &pacman.Pacman{
			Pack: pac,
		}
	case "debian":
		pcker = &debian.Debian{
			Pack: pac,
		}
	case "redhat":
		pcker = &redhat.Redhat{
			Pack: pac,
		}
	default:
		system := distro
		if release != "" {
			system += "-" + release
		}

		err = &UnknownSystem{
			errors.Newf("packer: Unkown system %s", system),
		}
		return
	}

	return
}
Example #12
0
func (conj *conjunctExpression) SerializeSql(out *bytes.Buffer) (err error) {
	if len(conj.expressions) == 0 {
		return errors.Newf(
			"Empty conjunction.  Generated sql: %s",
			out.String())
	}

	clauses := make([]Clause, len(conj.expressions), len(conj.expressions))
	for i, expr := range conj.expressions {
		clauses[i] = expr
	}

	use_parentheses := len(clauses) > 1
	if use_parentheses {
		out.WriteByte('(')
	}

	if err = serializeClauses(clauses, conj.conjunction, out); err != nil {
		return
	}

	if use_parentheses {
		out.WriteByte(')')
	}

	return nil
}
Example #13
0
func (arith *arithmeticExpression) SerializeSql(out *bytes.Buffer) (err error) {
	if len(arith.expressions) == 0 {
		return errors.Newf(
			"Empty arithmetic expression.  Generated sql: %s",
			out.String())
	}

	clauses := make([]Clause, len(arith.expressions), len(arith.expressions))
	for i, expr := range arith.expressions {
		clauses[i] = expr
	}

	useParentheses := len(clauses) > 1
	if useParentheses {
		out.WriteByte('(')
	}

	if err = serializeClauses(clauses, arith.operator, out); err != nil {
		return
	}

	if useParentheses {
		out.WriteByte(')')
	}

	return nil
}
Example #14
0
func (*singletonSuite) TestGet(c *C) {
	callCount := 0
	init := func() (interface{}, error) {
		callCount++

		if callCount < 2 {
			return nil, errors.Newf("fail")
		}
		v := 5
		return &v, nil
	}

	s := NewSingleton(init)
	// Verify init hasn't been called yet
	c.Assert(callCount, Equals, 0)

	// Verify init gets called with Get()
	_, err := s.Get()
	c.Assert(err, NotNil)
	c.Assert(callCount, Equals, 1)

	// Verify failed init gets retried with Get()
	data1, err := s.Get()
	c.Assert(err, IsNil)
	c.Assert(callCount, Equals, 2)
	c.Assert(*(data1.(*int)), Equals, 5)

	// Verify that subsequent Get() after a successful one return the same object and don't call
	// init
	data2, err := s.Get()
	c.Assert(err, IsNil)
	c.Assert(callCount, Equals, 2)
	c.Assert(data1, Equals, data2)
}
Example #15
0
File: cmd.go Project: pacur/pacur
func Parse() (err error) {
	flag.Parse()

	cmd := flag.Arg(0)
	switch cmd {
	case "build":
		err = Build()
	case "create":
		err = Create()
	case "project":
		err = Project()
	case "pull":
		err = utils.PullContainers()
	case "genkey":
		err = GenKey()
	case "list-targets":
		err = ListTargets()
	default:
		err = &UnknownCommand{
			errors.Newf("cmd: Unknown command '%s'", cmd),
		}
	}

	return
}
Example #16
0
// Note: this is equivalent to net_field_length in sql-common/pack.c
func readFieldLength(valBytes []byte) (
	length uint64,
	remaining []byte,
	err error) {

	if len(valBytes) == 0 {
		return 0, nil, errors.New("Empty field length input")
	}

	val := uint64(valBytes[0])
	if val < 251 {
		return val, valBytes[1:], nil
	} else if val == 251 {
		return NullLength, valBytes[1:], nil
	}
	size := 9
	if val == 252 {
		size = 3
	} else if val == 253 {
		size = 4
	}
	if len(valBytes) < size {
		return 0, nil, errors.Newf(
			"Invalid field length input (expected at least %d bytes)",
			size)
	}
	// NOTE: mysql's net_field_length implementation is somewhat broken.
	// In particular, when net_store_length encode a ulong using 8 bytes,
	// net_field_length will only read the first 4 bytes, and ignore the
	// rest ....
	return bytesToLEUint(valBytes[1:size]), valBytes[size:], nil
}
Example #17
0
func (c *inExpression) SerializeSql(out *bytes.Buffer) error {
	if c.err != nil {
		return errors.Wrap(c.err, "Invalid IN expression")
	}

	if c.lhs == nil {
		return errors.Newf(
			"lhs of in expression is nil.  Generated sql: %s",
			out.String())
	}

	// We'll serialize the lhs even if we don't need it to ensure no error
	buf := &bytes.Buffer{}

	err := c.lhs.SerializeSql(buf)
	if err != nil {
		return err
	}

	if c.rhs == nil {
		out.WriteString("FALSE")
		return nil
	}

	out.WriteString(buf.String())
	out.WriteString(" IN ")

	err = c.rhs.SerializeSql(out)
	if err != nil {
		return err
	}

	return nil
}
Example #18
0
func (m *Mirror) Create() (err error) {
	keyPath := filepath.Join(m.Root, "sign.key")

	m.Signing, err = utils.Exists(keyPath)
	if err != nil {
		return
	}

	if m.Signing {
		err = signing.ImportKey(keyPath)
		if err != nil {
			return
		}

		err = signing.CreateRedhatConf()
		if err != nil {
			return
		}
	}

	switch constants.DistroPack[m.Distro] {
	case "pacman":
		err = m.createPacman()
	case "debian":
		err = m.createDebian()
	case "redhat":
		err = m.createRedhat()
	default:
		err = &UnknownType{
			errors.Newf("mirror: Unknown type '%s'", m.Distro),
		}
	}

	return
}
Example #19
0
// ConverAssignRowNullable is the same as ConvertAssignRow except that it allows
// nil as a value for the row or any of the row values. In thoses cases, the
// corresponding values are ignored.
func ConvertAssignRowNullable(row []Value, dest ...interface{}) error {
	if len(row) != len(dest) {
		return errors.Newf(
			"# of row entries %d does not match # of destinations %d",
			len(row),
			len(dest))
	}

	if row == nil {
		return nil
	}

	for i := 0; i < len(row); i++ {
		if row[i].IsNull() {
			continue
		}

		err := ConvertAssign(row[i], dest[i])
		if err != nil {
			return err
		}
	}

	return nil
}
Example #20
0
func (s *lockStatementImpl) String(database string) (sql string, err error) {
	if !validIdentifierName(database) {
		return "", errors.New("Invalid database name specified")
	}

	if len(s.locks) == 0 {
		return "", errors.New("No locks added")
	}

	buf := new(bytes.Buffer)
	buf.WriteString("LOCK TABLES ")

	for idx, lock := range s.locks {
		if lock.t == nil {
			return "", errors.Newf("nil table.  Generated sql: %s", buf.String())
		}

		if err = lock.t.SerializeSql(database, buf); err != nil {
			return
		}

		if lock.w {
			buf.WriteString(" WRITE")
		} else {
			buf.WriteString(" READ")
		}

		if idx != len(s.locks)-1 {
			buf.WriteString(", ")
		}
	}

	return buf.String(), nil
}
// See ResourcePool for documentation.
func (p *RoundRobinResourcePool) Register(resourceLocation string) error {
	if resourceLocation == "" {
		return errors.New("Registering invalid resource location")
	}

	p.rwMutex.Lock()
	defer p.rwMutex.Unlock()

	if p.isLameDuck {
		return errors.Newf(
			"Cannot register %s to lame duck resource pool",
			resourceLocation)
	}

	for _, locPool := range p.pools {
		if locPool.ResourceLocation == resourceLocation {
			return nil
		}
	}

	pool := p.createPool(p.options)
	if err := pool.Register(resourceLocation); err != nil {
		return err
	}

	p.pools = append(
		p.pools,
		&ResourceLocationPool{
			ResourceLocation: resourceLocation,
			Pool:             pool,
		})

	shuffle(p.pools)
	return nil
}
// Returns instance that isn't marked down, if all instances are
// marked as down it will just choose a next one.
func (pool *LoadBalancedPool) getInstance() (
	idx int,
	instance *instancePool,
	isDown bool,
	err error) {
	pool.lock.RLock()
	defer pool.lock.RUnlock()
	if len(pool.instanceList) == 0 {
		return 0, nil, false, errors.Newf("no available instances")
	}
	now := time.Now().Unix()
	for i := 0; i < len(pool.instanceList); i++ {
		switch pool.strategy {
		case LBRoundRobin:
			// In RoundRobin strategy instanceIdx keeps changing, to
			// achieve round robin load balancing.
			instanceIdx := atomic.AddUint64(&pool.instanceIdx, 1)
			idx = int(instanceIdx % uint64(len(pool.instanceList)))
		case LBSortedFixed:
			// In SortedFixed strategy instances are always traversed in same
			// exact order.
			idx = i
		case LBShuffledFixed:
			// In ShuffledFixed strategy instances are also always traversed in
			// same exact order.
			idx = i
		}

		if pool.markDownUntil[idx] < now {
			break
		}
	}
	return idx, pool.instanceList[idx], (pool.markDownUntil[idx] >= now), nil
}
Example #23
0
func (s *unionStatementImpl) String(database string) (sql string, err error) {
	// XXX(teisenbe): Once sqlproxy gets fixed, re-parenthesis the UNION selects
	// We don't have any use cases where they matter, but if one were to use limits/order by with
	// selects and unions, it could be problematic
	if len(s.selects) == 0 {
		return "", errors.Newf("Union statement must have at least one SELECT")
	}
	if len(s.selects) == 1 {
		return s.selects[0].String(database)
	}

	buf := new(bytes.Buffer)
	for i, statement := range s.selects {
		if i != 0 {
			buf.WriteString(" UNION ")
		}
		//buf.WriteString("(")
		selectSql, err := statement.String(database)
		if err != nil {
			return "", err
		}
		buf.WriteString(selectSql)
		//buf.WriteString(")")
	}
	return buf.String(), nil
}
Example #24
0
func (f *FileLock) performLock(flockHow int) (performErr error) {
	if f.fileH != nil {
		return errors.Newf("FileLock is already acquired!")
	}

	filePath := path.Join(f.path, f.prefix+f.name)
	// GoLang os.OpenFile creates file with FD_CLOEXEC flag already set on it.
	// This means file will get closed automatically once the process exits,
	// thus we dont need to manually set that flag.
	fileH, err := os.Create(filePath)
	if err != nil {
		return err
	}
	defer func() {
		if performErr != nil {
			_ = fileH.Close()
		}
	}()

	if err := syscall.Flock(int(fileH.Fd()), flockHow); err != nil {
		return err
	}

	f.fileH = fileH
	return nil
}
func (r *logFileV4EventReader) maybeCheckLogFormatVersion() error {
	if r.passedLogFormatVersionCheck {
		return nil
	}

	headerBytes, err := r.peekHeaderBytes(sizeOfFormatVersionHeader)
	if err != nil {
		return err
	}

	header := formatVersionHeader{}

	_, err = readLittleEndian(headerBytes, &header)
	if err != nil {
		return err
	}

	if version := header.version(); version != 4 {
		return errors.Newf(
			"Binary log reader does not support V%d binlog format",
			version)
	}

	r.passedLogFormatVersionCheck = true
	return nil
}
Example #26
0
func Project() (err error) {
	path, err := os.Getwd()
	if err != nil {
		err = &FileError{
			errors.Wrapf(err, "cmd: Failed to get working directory"),
		}
		return
	}

	proj := &project.Project{
		Root: path,
	}
	err = proj.Init()
	if err != nil {
		return
	}

	cmd := flag.Arg(1)
	switch cmd {
	case "init":
		err = proj.InitProject()
	case "build":
		err = proj.Build(flag.Arg(2))
	case "repo":
		err = proj.Repo(flag.Arg(2))
	default:
		err = &UnknownCommand{
			errors.Newf("cmd: Unknown cmd '%s'", cmd),
		}
	}

	return
}
Example #27
0
func (this *watcher) doDel(path string) error {
	info, found := this.watchedByPath[path]
	if !found {
		return errors.Newf("can't remove non-existent kevent watch for: %s", path)
	}

	var kbuf [1]syscall.Kevent_t
	watchEntry := &kbuf[0]
	syscall.SetKevent(watchEntry, info.fd, syscall.EVFILT_VNODE, syscall.EV_DELETE)
	entryFlags := watchEntry.Flags
	success, errno := syscall.Kevent(this.kq, kbuf[:], nil, nil)
	if success == sysCallFailed {
		return os.NewSyscallError("kevent_rm_watch", errno)
	} else if entryFlags&syscall.EV_ERROR == syscall.EV_ERROR {
		return errors.New("kevent rm error")
	}
	syscall.Close(info.fd)

	//Remove childs if it's directory
	for _, child := range info.childes {
		this.doDel(child)
	}

	delete(this.watchedByPath, path)
	delete(this.watchedByFD, info.fd)

	return nil
}
Example #28
0
// This decrements the key's counter by delta.  If the counter does not
// exist, one of two things may happen:
// 1. If the expiration value is all one-bits (0xffffffff), the operation
// will fail with StatusNotFound.
// 2. For all other expiration values, the operation will succeed by
// seeding the value for this key with the provided initValue to expire
// with the provided expiration time. The flags will be set to zero.
//
// NOTE:
// 1. If you want to set the value of the counter with add/set/replace,
// the objects data must be the ascii representation of the value and
// not the byte values of a 64 bit integer.
// 2. Decrementing a counter will never result in a "negative value" (or
// cause the counter to "wrap"). instead the counter is set to 0.
func (c *MockClient) Decrement(
	key string,
	delta uint64,
	initValue uint64,
	expiration uint32) CountResponse {

	return NewCountErrorResponse(key, errors.Newf("Decrement not implemented"))
}
Example #29
0
func (r *Redhat) Build() (err error) {
	err = r.makeDirs()
	if err != nil {
		return
	}
	defer r.remDirs()

	err = r.createSpec([]string{})
	if err != nil {
		return
	}

	err = r.rpmBuild()
	if err != nil {
		return
	}

	files, err := r.getFiles()
	if err != nil {
		return
	}

	if len(files) == 0 {
		err = &BuildError{
			errors.Newf("redhat: Failed to find rpms files '%s'",
				r.rpmsDir),
		}
		return
	}

	r.remDirs()
	err = r.makeDirs()
	if err != nil {
		return
	}

	err = r.createSpec(files)
	if err != nil {
		return
	}

	err = r.rpmBuild()
	if err != nil {
		return
	}

	err = r.clean()
	if err != nil {
		return
	}

	err = r.copy()
	if err != nil {
		return
	}

	return
}
Example #30
0
func (c *ShardedClient) connectionError(shard int, err error) error {
	if err == nil {
		return errors.Newf(
			"Connection unavailable for memcache shard %d", shard)
	}
	return errors.Wrapf(
		err,
		"Connection unavailable for memcache shard %d", shard)
}