hanayo/vendor/github.com/valyala/fasthttp/bytesconv.go
2019-02-23 13:29:15 +00:00

423 lines
9.0 KiB
Go

package fasthttp
import (
"bufio"
"bytes"
"errors"
"fmt"
"io"
"math"
"net"
"reflect"
"sync"
"time"
"unsafe"
)
// AppendHTMLEscape appends html-escaped s to dst and returns the extended dst.
func AppendHTMLEscape(dst []byte, s string) []byte {
var prev int
var sub string
for i, n := 0, len(s); i < n; i++ {
sub = ""
switch s[i] {
case '<':
sub = "&lt;"
case '>':
sub = "&gt;"
case '"':
sub = "&quot;"
case '\'':
sub = "&#39;"
}
if len(sub) > 0 {
dst = append(dst, s[prev:i]...)
dst = append(dst, sub...)
prev = i + 1
}
}
return append(dst, s[prev:]...)
}
// AppendHTMLEscapeBytes appends html-escaped s to dst and returns
// the extended dst.
func AppendHTMLEscapeBytes(dst, s []byte) []byte {
return AppendHTMLEscape(dst, b2s(s))
}
// AppendIPv4 appends string representation of the given ip v4 to dst
// and returns the extended dst.
func AppendIPv4(dst []byte, ip net.IP) []byte {
ip = ip.To4()
if ip == nil {
return append(dst, "non-v4 ip passed to AppendIPv4"...)
}
dst = AppendUint(dst, int(ip[0]))
for i := 1; i < 4; i++ {
dst = append(dst, '.')
dst = AppendUint(dst, int(ip[i]))
}
return dst
}
var errEmptyIPStr = errors.New("empty ip address string")
// ParseIPv4 parses ip address from ipStr into dst and returns the extended dst.
func ParseIPv4(dst net.IP, ipStr []byte) (net.IP, error) {
if len(ipStr) == 0 {
return dst, errEmptyIPStr
}
if len(dst) < net.IPv4len {
dst = make([]byte, net.IPv4len)
}
copy(dst, net.IPv4zero)
dst = dst.To4()
if dst == nil {
panic("BUG: dst must not be nil")
}
b := ipStr
for i := 0; i < 3; i++ {
n := bytes.IndexByte(b, '.')
if n < 0 {
return dst, fmt.Errorf("cannot find dot in ipStr %q", ipStr)
}
v, err := ParseUint(b[:n])
if err != nil {
return dst, fmt.Errorf("cannot parse ipStr %q: %s", ipStr, err)
}
if v > 255 {
return dst, fmt.Errorf("cannot parse ipStr %q: ip part cannot exceed 255: parsed %d", ipStr, v)
}
dst[i] = byte(v)
b = b[n+1:]
}
v, err := ParseUint(b)
if err != nil {
return dst, fmt.Errorf("cannot parse ipStr %q: %s", ipStr, err)
}
if v > 255 {
return dst, fmt.Errorf("cannot parse ipStr %q: ip part cannot exceed 255: parsed %d", ipStr, v)
}
dst[3] = byte(v)
return dst, nil
}
// AppendHTTPDate appends HTTP-compliant (RFC1123) representation of date
// to dst and returns the extended dst.
func AppendHTTPDate(dst []byte, date time.Time) []byte {
dst = date.In(time.UTC).AppendFormat(dst, time.RFC1123)
copy(dst[len(dst)-3:], strGMT)
return dst
}
// ParseHTTPDate parses HTTP-compliant (RFC1123) date.
func ParseHTTPDate(date []byte) (time.Time, error) {
return time.Parse(time.RFC1123, b2s(date))
}
// AppendUint appends n to dst and returns the extended dst.
func AppendUint(dst []byte, n int) []byte {
if n < 0 {
panic("BUG: int must be positive")
}
var b [20]byte
buf := b[:]
i := len(buf)
var q int
for n >= 10 {
i--
q = n / 10
buf[i] = '0' + byte(n-q*10)
n = q
}
i--
buf[i] = '0' + byte(n)
dst = append(dst, buf[i:]...)
return dst
}
// ParseUint parses uint from buf.
func ParseUint(buf []byte) (int, error) {
v, n, err := parseUintBuf(buf)
if n != len(buf) {
return -1, errUnexpectedTrailingChar
}
return v, err
}
var (
errEmptyInt = errors.New("empty integer")
errUnexpectedFirstChar = errors.New("unexpected first char found. Expecting 0-9")
errUnexpectedTrailingChar = errors.New("unexpected traling char found. Expecting 0-9")
errTooLongInt = errors.New("too long int")
)
func parseUintBuf(b []byte) (int, int, error) {
n := len(b)
if n == 0 {
return -1, 0, errEmptyInt
}
v := 0
for i := 0; i < n; i++ {
c := b[i]
k := c - '0'
if k > 9 {
if i == 0 {
return -1, i, errUnexpectedFirstChar
}
return v, i, nil
}
if i >= maxIntChars {
return -1, i, errTooLongInt
}
v = 10*v + int(k)
}
return v, n, nil
}
var (
errEmptyFloat = errors.New("empty float number")
errDuplicateFloatPoint = errors.New("duplicate point found in float number")
errUnexpectedFloatEnd = errors.New("unexpected end of float number")
errInvalidFloatExponent = errors.New("invalid float number exponent")
errUnexpectedFloatChar = errors.New("unexpected char found in float number")
)
// ParseUfloat parses unsigned float from buf.
func ParseUfloat(buf []byte) (float64, error) {
if len(buf) == 0 {
return -1, errEmptyFloat
}
b := buf
var v uint64
var offset = 1.0
var pointFound bool
for i, c := range b {
if c < '0' || c > '9' {
if c == '.' {
if pointFound {
return -1, errDuplicateFloatPoint
}
pointFound = true
continue
}
if c == 'e' || c == 'E' {
if i+1 >= len(b) {
return -1, errUnexpectedFloatEnd
}
b = b[i+1:]
minus := -1
switch b[0] {
case '+':
b = b[1:]
minus = 1
case '-':
b = b[1:]
default:
minus = 1
}
vv, err := ParseUint(b)
if err != nil {
return -1, errInvalidFloatExponent
}
return float64(v) * offset * math.Pow10(minus*int(vv)), nil
}
return -1, errUnexpectedFloatChar
}
v = 10*v + uint64(c-'0')
if pointFound {
offset /= 10
}
}
return float64(v) * offset, nil
}
var (
errEmptyHexNum = errors.New("empty hex number")
errTooLargeHexNum = errors.New("too large hex number")
)
func readHexInt(r *bufio.Reader) (int, error) {
n := 0
i := 0
var k int
for {
c, err := r.ReadByte()
if err != nil {
if err == io.EOF && i > 0 {
return n, nil
}
return -1, err
}
k = hexbyte2int(c)
if k < 0 {
if i == 0 {
return -1, errEmptyHexNum
}
r.UnreadByte()
return n, nil
}
if i >= maxHexIntChars {
return -1, errTooLargeHexNum
}
n = (n << 4) | k
i++
}
}
var hexIntBufPool sync.Pool
func writeHexInt(w *bufio.Writer, n int) error {
if n < 0 {
panic("BUG: int must be positive")
}
v := hexIntBufPool.Get()
if v == nil {
v = make([]byte, maxHexIntChars+1)
}
buf := v.([]byte)
i := len(buf) - 1
for {
buf[i] = int2hexbyte(n & 0xf)
n >>= 4
if n == 0 {
break
}
i--
}
_, err := w.Write(buf[i:])
hexIntBufPool.Put(v)
return err
}
func int2hexbyte(n int) byte {
if n < 10 {
return '0' + byte(n)
}
return 'a' + byte(n) - 10
}
func hexCharUpper(c byte) byte {
if c < 10 {
return '0' + c
}
return c - 10 + 'A'
}
var hex2intTable = func() []byte {
b := make([]byte, 255)
for i := byte(0); i < 255; i++ {
c := byte(0)
if i >= '0' && i <= '9' {
c = 1 + i - '0'
} else if i >= 'a' && i <= 'f' {
c = 1 + i - 'a' + 10
} else if i >= 'A' && i <= 'F' {
c = 1 + i - 'A' + 10
}
b[i] = c
}
return b
}()
func hexbyte2int(c byte) int {
return int(hex2intTable[c]) - 1
}
const toLower = 'a' - 'A'
func uppercaseByte(p *byte) {
c := *p
if c >= 'a' && c <= 'z' {
*p = c - toLower
}
}
func lowercaseByte(p *byte) {
c := *p
if c >= 'A' && c <= 'Z' {
*p = c + toLower
}
}
func lowercaseBytes(b []byte) {
for i, n := 0, len(b); i < n; i++ {
lowercaseByte(&b[i])
}
}
// b2s converts byte slice to a string without memory allocation.
// See https://groups.google.com/forum/#!msg/Golang-Nuts/ENgbUzYvCuU/90yGx7GUAgAJ .
//
// Note it may break if string and/or slice header will change
// in the future go versions.
func b2s(b []byte) string {
return *(*string)(unsafe.Pointer(&b))
}
// s2b converts string to a byte slice without memory allocation.
//
// Note it may break if string and/or slice header will change
// in the future go versions.
func s2b(s string) []byte {
sh := (*reflect.StringHeader)(unsafe.Pointer(&s))
bh := reflect.SliceHeader{
Data: sh.Data,
Len: sh.Len,
Cap: sh.Len,
}
return *(*[]byte)(unsafe.Pointer(&bh))
}
// AppendQuotedArg appends url-encoded src to dst and returns appended dst.
func AppendQuotedArg(dst, src []byte) []byte {
for _, c := range src {
// See http://www.w3.org/TR/html5/forms.html#form-submission-algorithm
if c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z' || c >= '0' && c <= '9' ||
c == '*' || c == '-' || c == '.' || c == '_' {
dst = append(dst, c)
} else {
dst = append(dst, '%', hexCharUpper(c>>4), hexCharUpper(c&15))
}
}
return dst
}
func appendQuotedPath(dst, src []byte) []byte {
for _, c := range src {
if c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z' || c >= '0' && c <= '9' ||
c == '/' || c == '.' || c == ',' || c == '=' || c == ':' || c == '&' || c == '~' || c == '-' || c == '_' {
dst = append(dst, c)
} else {
dst = append(dst, '%', hexCharUpper(c>>4), hexCharUpper(c&15))
}
}
return dst
}
// EqualBytesStr returns true if string(b) == s.
//
// This function has no performance benefits comparing to string(b) == s.
// It is left here for backwards compatibility only.
//
// This function is deperecated and may be deleted soon.
func EqualBytesStr(b []byte, s string) bool {
return string(b) == s
}
// AppendBytesStr appends src to dst and returns the extended dst.
//
// This function has no performance benefits comparing to append(dst, src...).
// It is left here for backwards compatibility only.
//
// This function is deprecated and may be deleted soon.
func AppendBytesStr(dst []byte, src string) []byte {
return append(dst, src...)
}