import (
"bufio"
"bytes"
+ "fmt"
"io"
"io/ioutil"
"mime"
"net/textproto"
"os"
"regexp"
- "strings"
)
var headerRegexp *regexp.Regexp = regexp.MustCompile("^([a-zA-Z0-9\\-]+): *([^\r\n]+)")
// NewReader creates a new multipart Reader reading from r using the
// given MIME boundary.
func NewReader(reader io.Reader, boundary string) Reader {
+ b := []byte("\r\n--" + boundary + "--")
return &multiReader{
- boundary: boundary,
- dashBoundary: "--" + boundary,
- endLine: "--" + boundary + "--",
- bufReader: bufio.NewReader(reader),
+ bufReader: bufio.NewReader(reader),
+
+ nlDashBoundary: b[:len(b)-2],
+ dashBoundaryDash: b[2:],
+ dashBoundary: b[2 : len(b)-2],
}
}
// Implementation ....
-func newPart(mr *multiReader) (bp *Part, err os.Error) {
- bp = new(Part)
- bp.Header = make(map[string][]string)
- bp.mr = mr
- bp.buffer = new(bytes.Buffer)
- if err = bp.populateHeaders(); err != nil {
- bp = nil
+func newPart(mr *multiReader) (*Part, os.Error) {
+ bp := &Part{
+ Header: make(map[string][]string),
+ mr: mr,
+ buffer: new(bytes.Buffer),
}
- return
+ if err := bp.populateHeaders(); err != nil {
+ return nil, err
+ }
+ return bp, nil
}
func (bp *Part) populateHeaders() os.Error {
// Read reads the body of a part, after its headers and before the
// next part (if any) begins.
func (bp *Part) Read(p []byte) (n int, err os.Error) {
- for {
- if bp.buffer.Len() >= len(p) {
- // Internal buffer of unconsumed data is large enough for
- // the read request. No need to parse more at the moment.
- break
- }
- if !bp.mr.ensureBufferedLine() {
- return 0, io.ErrUnexpectedEOF
- }
- if bp.mr.bufferedLineIsBoundary() {
- // Don't consume this line
- break
- }
+ if bp.buffer.Len() >= len(p) {
+ // Internal buffer of unconsumed data is large enough for
+ // the read request. No need to parse more at the moment.
+ return bp.buffer.Read(p)
+ }
+ peek, err := bp.mr.bufReader.Peek(4096) // TODO(bradfitz): add buffer size accessor
+ unexpectedEof := err == os.EOF
+ if err != nil && !unexpectedEof {
+ return 0, fmt.Errorf("multipart: Part Read: %v", err)
+ }
+ if peek == nil {
+ panic("nil peek buf")
+ }
- // Write all of this line, except the final CRLF
- s := *bp.mr.bufferedLine
- if strings.HasSuffix(s, "\r\n") {
- bp.mr.consumeLine()
- if !bp.mr.ensureBufferedLine() {
- return 0, io.ErrUnexpectedEOF
- }
- if bp.mr.bufferedLineIsBoundary() {
- // The final \r\n isn't ours. It logically belongs
- // to the boundary line which follows.
- bp.buffer.WriteString(s[0 : len(s)-2])
- } else {
- bp.buffer.WriteString(s)
- }
- break
- }
- if strings.HasSuffix(s, "\n") {
- bp.buffer.WriteString(s)
- bp.mr.consumeLine()
- continue
+ // Search the peek buffer for "\r\n--boundary". If found,
+ // consume everything up to the boundary. If not, consume only
+ // as much of the peek buffer as cannot hold the boundary
+ // string.
+ nCopy := 0
+ foundBoundary := false
+ if idx := bytes.Index(peek, bp.mr.nlDashBoundary); idx != -1 {
+ nCopy = idx
+ foundBoundary = true
+ } else if safeCount := len(peek) - len(bp.mr.nlDashBoundary); safeCount > 0 {
+ nCopy = safeCount
+ } else if unexpectedEof {
+ // If we've run out of peek buffer and the boundary
+ // wasn't found (and can't possibly fit), we must have
+ // hit the end of the file unexpectedly.
+ return 0, io.ErrUnexpectedEOF
+ }
+ if nCopy > 0 {
+ if _, err := io.Copyn(bp.buffer, bp.mr.bufReader, int64(nCopy)); err != nil {
+ return 0, err
}
- return 0, os.NewError("multipart parse error during Read; unexpected line: " + s)
}
- return bp.buffer.Read(p)
+ n, err = bp.buffer.Read(p)
+ if err == os.EOF && !foundBoundary {
+ // If the boundary hasn't been reached there's more to
+ // read, so don't pass through an EOF from the buffer
+ err = nil
+ }
+ return
}
func (bp *Part) Close() os.Error {
}
type multiReader struct {
- boundary string
- dashBoundary string // --boundary
- endLine string // --boundary--
+ bufReader *bufio.Reader
- bufferedLine *string
-
- bufReader *bufio.Reader
currentPart *Part
partsRead int
-}
-func (mr *multiReader) eof() bool {
- return mr.bufferedLine == nil &&
- !mr.readLine()
-}
-
-func (mr *multiReader) readLine() bool {
- lineBytes, err := mr.bufReader.ReadSlice('\n')
- if err != nil {
- // TODO: care about err being EOF or not?
- return false
- }
- line := string(lineBytes)
- mr.bufferedLine = &line
- return true
-}
-
-func (mr *multiReader) bufferedLineIsBoundary() bool {
- return strings.HasPrefix(*mr.bufferedLine, mr.dashBoundary)
-}
-
-func (mr *multiReader) ensureBufferedLine() bool {
- if mr.bufferedLine == nil {
- return mr.readLine()
- }
- return true
-}
-
-func (mr *multiReader) consumeLine() {
- mr.bufferedLine = nil
+ nlDashBoundary, dashBoundaryDash, dashBoundary []byte
}
func (mr *multiReader) NextPart() (*Part, os.Error) {
mr.currentPart.Close()
}
+ expectNewPart := false
for {
- if mr.eof() {
- return nil, io.ErrUnexpectedEOF
+ line, err := mr.bufReader.ReadSlice('\n')
+ if err != nil {
+ return nil, fmt.Errorf("multipart: NextPart: %v", err)
}
- if isBoundaryDelimiterLine(*mr.bufferedLine, mr.dashBoundary) {
- mr.consumeLine()
+ if mr.isBoundaryDelimiterLine(line) {
mr.partsRead++
bp, err := newPart(mr)
if err != nil {
return bp, nil
}
- if hasPrefixThenNewline(*mr.bufferedLine, mr.endLine) {
- mr.consumeLine()
+ if hasPrefixThenNewline(line, mr.dashBoundaryDash) {
// Expected EOF (no error)
+ // TODO(bradfitz): should return an os.EOF error here, not using nil for errors
return nil, nil
}
+ if expectNewPart {
+ return nil, fmt.Errorf("multipart: expecting a new Part; got line %q", string(line))
+ }
+
if mr.partsRead == 0 {
// skip line
- mr.consumeLine()
continue
}
- return nil, os.NewError("Unexpected line in Next().")
+ if bytes.Equal(line, []byte("\r\n")) {
+ // Consume the "\r\n" separator between the
+ // body of the previous part and the boundary
+ // line we now expect will follow. (either a
+ // new part or the end boundary)
+ expectNewPart = true
+ continue
+ }
+
+ return nil, fmt.Errorf("multipart: unexpected line in Next(): %q", line)
}
panic("unreachable")
}
-func isBoundaryDelimiterLine(line, dashPrefix string) bool {
+func (mr *multiReader) isBoundaryDelimiterLine(line []byte) bool {
// http://tools.ietf.org/html/rfc2046#section-5.1
// The boundary delimiter line is then defined as a line
// consisting entirely of two hyphen characters ("-",
// decimal value 45) followed by the boundary parameter
// value from the Content-Type header field, optional linear
// whitespace, and a terminating CRLF.
- if !strings.HasPrefix(line, dashPrefix) {
+ if !bytes.HasPrefix(line, mr.dashBoundary) {
return false
}
- if strings.HasSuffix(line, "\r\n") {
- return onlyHorizontalWhitespace(line[len(dashPrefix) : len(line)-2])
+ if bytes.HasSuffix(line, []byte("\r\n")) {
+ return onlyHorizontalWhitespace(line[len(mr.dashBoundary) : len(line)-2])
}
// Violate the spec and also support newlines without the
// carriage return...
- if strings.HasSuffix(line, "\n") {
- return onlyHorizontalWhitespace(line[len(dashPrefix) : len(line)-1])
+ if bytes.HasSuffix(line, []byte("\n")) {
+ return onlyHorizontalWhitespace(line[len(mr.dashBoundary) : len(line)-1])
}
return false
}
-func onlyHorizontalWhitespace(s string) bool {
- for i := 0; i < len(s); i++ {
- if s[i] != ' ' && s[i] != '\t' {
+func onlyHorizontalWhitespace(s []byte) bool {
+ for _, b := range s {
+ if b != ' ' && b != '\t' {
return false
}
}
return true
}
-func hasPrefixThenNewline(s, prefix string) bool {
- return strings.HasPrefix(s, prefix) &&
- (len(s) == len(prefix)+1 && strings.HasSuffix(s, "\n") ||
- len(s) == len(prefix)+2 && strings.HasSuffix(s, "\r\n"))
+func hasPrefixThenNewline(s, prefix []byte) bool {
+ return bytes.HasPrefix(s, prefix) &&
+ (len(s) == len(prefix)+1 && s[len(s)-1] == '\n' ||
+ len(s) == len(prefix)+2 && bytes.HasSuffix(s, []byte("\r\n")))
}
"bytes"
"fmt"
"io"
+ "io/ioutil"
"json"
"os"
- "regexp"
"strings"
"testing"
)
func TestHorizontalWhitespace(t *testing.T) {
- if !onlyHorizontalWhitespace(" \t") {
+ if !onlyHorizontalWhitespace([]byte(" \t")) {
t.Error("expected pass")
}
- if onlyHorizontalWhitespace("foo bar") {
+ if onlyHorizontalWhitespace([]byte("foo bar")) {
t.Error("expected failure")
}
}
func TestBoundaryLine(t *testing.T) {
- boundary := "myBoundary"
- prefix := "--" + boundary
- if !isBoundaryDelimiterLine("--myBoundary\r\n", prefix) {
+ mr := NewReader(strings.NewReader(""), "myBoundary").(*multiReader)
+ if !mr.isBoundaryDelimiterLine([]byte("--myBoundary\r\n")) {
t.Error("expected")
}
- if !isBoundaryDelimiterLine("--myBoundary \r\n", prefix) {
+ if !mr.isBoundaryDelimiterLine([]byte("--myBoundary \r\n")) {
t.Error("expected")
}
- if !isBoundaryDelimiterLine("--myBoundary \n", prefix) {
+ if !mr.isBoundaryDelimiterLine([]byte("--myBoundary \n")) {
t.Error("expected")
}
- if isBoundaryDelimiterLine("--myBoundary bogus \n", prefix) {
+ if mr.isBoundaryDelimiterLine([]byte("--myBoundary bogus \n")) {
t.Error("expected fail")
}
- if isBoundaryDelimiterLine("--myBoundary bogus--", prefix) {
+ if mr.isBoundaryDelimiterLine([]byte("--myBoundary bogus--")) {
t.Error("expected fail")
}
}
}
}
-func TestMultipart(t *testing.T) {
+var longLine = strings.Repeat("\n\n\r\r\r\n\r\000", (1<<20)/8)
+
+func testMultipartBody() string {
testBody := `
This is a multi-part message. This line is ignored.
--MyBoundary
My value
The end.
--MyBoundary
+name: bigsection
+
+[longline]
+--MyBoundary
Header1: value1b
HEADER2: value2b
foo-bar: bazb
never read data
--MyBoundary--
+
+
+useless trailer
`
- testBody = regexp.MustCompile("\n").ReplaceAllString(testBody, "\r\n")
- bodyReader := strings.NewReader(testBody)
+ testBody = strings.Replace(testBody, "\n", "\r\n", -1)
+ return strings.Replace(testBody, "[longline]", longLine, 1)
+}
+
+func TestMultipart(t *testing.T) {
+ bodyReader := strings.NewReader(testMultipartBody())
+ testMultipart(t, bodyReader)
+}
+
+func TestMultipartSlowInput(t *testing.T) {
+ bodyReader := strings.NewReader(testMultipartBody())
+ testMultipart(t, &slowReader{bodyReader})
+}
- reader := NewReader(bodyReader, "MyBoundary")
+func testMultipart(t *testing.T, r io.Reader) {
+ reader := NewReader(r, "MyBoundary")
buf := new(bytes.Buffer)
// Part1
t.Error("Expected Foo-Bar: baz")
}
buf.Reset()
- io.Copy(buf, part)
+ if _, err := io.Copy(buf, part); err != nil {
+ t.Errorf("part 1 copy: %v", err)
+ }
expectEq(t, "My value\r\nThe end.",
buf.String(), "Value of first part")
// Part2
part, err = reader.NextPart()
+ if err != nil {
+ t.Fatalf("Expected part2; got: %v", err)
+ return
+ }
+ if e, g := "bigsection", part.Header.Get("name"); e != g {
+ t.Errorf("part2's name header: expected %q, got %q", e, g)
+ }
+ buf.Reset()
+ if _, err := io.Copy(buf, part); err != nil {
+ t.Errorf("part 2 copy: %v", err)
+ }
+ s := buf.String()
+ if len(s) != len(longLine) {
+ t.Errorf("part2 body expected long line of length %d; got length %d",
+ len(longLine), len(s))
+ }
+ if s != longLine {
+ t.Errorf("part2 long body didn't match")
+ }
+
+ // Part3
+ part, err = reader.NextPart()
if part == nil || err != nil {
- t.Error("Expected part2")
+ t.Error("Expected part3")
return
}
if part.Header.Get("foo-bar") != "bazb" {
t.Error("Expected foo-bar: bazb")
}
buf.Reset()
- io.Copy(buf, part)
+ if _, err := io.Copy(buf, part); err != nil {
+ t.Errorf("part 3 copy: %v", err)
+ }
expectEq(t, "Line 1\r\nLine 2\r\nLine 3 ends in a newline, but just one.\r\n",
- buf.String(), "Value of second part")
+ buf.String(), "body of part 3")
- // Part3
+ // Part4
part, err = reader.NextPart()
if part == nil || err != nil {
- t.Error("Expected part3 without errors")
+ t.Error("Expected part 4 without errors")
return
}
- // Non-existent part4
+ // Non-existent part5
part, err = reader.NextPart()
if part != nil {
- t.Error("Didn't expect a third part.")
+ t.Error("Didn't expect a fifth part.")
}
if err != nil {
- t.Errorf("Unexpected error getting third part: %v", err)
+ t.Errorf("Unexpected error getting fifth part: %v", err)
}
}
t.Errorf("expected to read < %d bytes; read %d", maxReadThreshold, mr.n)
}
}
+
+func TestMultipartTruncated(t *testing.T) {
+ testBody := `
+This is a multi-part message. This line is ignored.
+--MyBoundary
+foo-bar: baz
+
+Oh no, premature EOF!
+`
+ body := strings.Replace(testBody, "\n", "\r\n", -1)
+ bodyReader := strings.NewReader(body)
+ r := NewReader(bodyReader, "MyBoundary")
+
+ part, err := r.NextPart()
+ if err != nil {
+ t.Fatalf("didn't get a part")
+ }
+ _, err = io.Copy(ioutil.Discard, part)
+ if err != io.ErrUnexpectedEOF {
+ t.Fatalf("expected error io.ErrUnexpectedEOF; got %v", err)
+ }
+}
+
+type slowReader struct {
+ r io.Reader
+}
+
+func (s *slowReader) Read(p []byte) (int, os.Error) {
+ if len(p) == 0 {
+ return s.r.Read(p)
+ }
+ return s.r.Read(p[:1])
+}