diff --git a/block.go b/block.go
index 6e1d1e2..4f36196 100644
--- a/block.go
+++ b/block.go
@@ -17,8 +17,14 @@ import (
"bytes"
)
-// parse block-level data
+// Parse block-level data.
+// Note: this function and many that it calls assume that
+// the input buffer ends with a newline.
func (parser *Parser) parseBlock(out *bytes.Buffer, data []byte) {
+ if len(data) == 0 || data[len(data)-1] != '\n' {
+ panic("parseBlock input is missing terminating newline")
+ }
+
// this is called recursively: enforce a maximum depth
if parser.nesting >= parser.maxNesting {
return
@@ -66,7 +72,7 @@ func (parser *Parser) parseBlock(out *bytes.Buffer, data []byte) {
if parser.isHRule(data) {
parser.r.HRule(out)
var i int
- for i = 0; i < len(data) && data[i] != '\n'; i++ {
+ for i = 0; data[i] != '\n'; i++ {
}
data = data[i:]
continue
@@ -159,10 +165,10 @@ func (parser *Parser) isPrefixHeader(data []byte) bool {
if parser.flags&EXTENSION_SPACE_HEADERS != 0 {
level := 0
- for level < len(data) && level < 6 && data[level] == '#' {
+ for level < 6 && data[level] == '#' {
level++
}
- if level < len(data) && data[level] != ' ' && data[level] != '\t' {
+ if data[level] != ' ' && data[level] != '\t' {
return false
}
}
@@ -171,13 +177,13 @@ func (parser *Parser) isPrefixHeader(data []byte) bool {
func (parser *Parser) blockPrefixHeader(out *bytes.Buffer, data []byte) int {
level := 0
- for level < len(data) && level < 6 && data[level] == '#' {
+ for level < 6 && data[level] == '#' {
level++
}
i, end := 0, 0
- for i = level; i < len(data) && (data[i] == ' ' || data[i] == '\t'); i++ {
+ for i = level; data[i] == ' ' || data[i] == '\t'; i++ {
}
- for end = i; end < len(data) && data[end] != '\n'; end++ {
+ for end = i; data[end] != '\n'; end++ {
}
skip := end
for end > 0 && data[end-1] == '#' {
@@ -197,16 +203,16 @@ func (parser *Parser) blockPrefixHeader(out *bytes.Buffer, data []byte) int {
}
func (parser *Parser) isUnderlinedHeader(data []byte) int {
- i := 0
-
// test of level 1 header
- if data[i] == '=' {
- for i = 1; i < len(data) && data[i] == '='; i++ {
- }
- for i < len(data) && (data[i] == ' ' || data[i] == '\t') {
+ if data[0] == '=' {
+ i := 1
+ for data[i] == '=' {
i++
}
- if i >= len(data) || data[i] == '\n' {
+ for data[i] == ' ' || data[i] == '\t' {
+ i++
+ }
+ if data[i] == '\n' {
return 1
} else {
return 0
@@ -214,13 +220,15 @@ func (parser *Parser) isUnderlinedHeader(data []byte) int {
}
// test of level 2 header
- if data[i] == '-' {
- for i = 1; i < len(data) && data[i] == '-'; i++ {
- }
- for i < len(data) && (data[i] == ' ' || data[i] == '\t') {
+ if data[0] == '-' {
+ i := 1
+ for data[i] == '-' {
i++
}
- if i >= len(data) || data[i] == '\n' {
+ for data[i] == ' ' || data[i] == '\t' {
+ i++
+ }
+ if data[i] == '\n' {
return 2
} else {
return 0
@@ -234,67 +242,21 @@ func (parser *Parser) blockHtml(out *bytes.Buffer, data []byte, doRender bool) i
var i, j int
// identify the opening tag
- if len(data) < 2 || data[0] != '<' {
+ if data[0] != '<' {
return 0
}
curtag, tagfound := parser.blockHtmlFindTag(data[1:])
// handle special cases
if !tagfound {
-
- // HTML comment, lax form
- if len(data) > 5 && data[1] == '!' && data[2] == '-' && data[3] == '-' {
- i = 5
-
- for i < len(data) && !(data[i-2] == '-' && data[i-1] == '-' && data[i] == '>') {
- i++
- }
- i++
-
- if i < len(data) {
- j = parser.isEmpty(data[i:])
- }
-
- if j > 0 {
- size := i + j
- if doRender {
- // trim newlines
- end := size
- for end > 0 && data[end-1] == '\n' {
- end--
- }
- parser.r.BlockHtml(out, data[:end])
- }
- return size
- }
+ // check for an HTML comment
+ if size := parser.blockHtmlComment(out, data, doRender); size > 0 {
+ return size
}
- // HR, which is the only self-closing block tag considered
- if len(data) > 4 &&
- (data[1] == 'h' || data[1] == 'H') &&
- (data[2] == 'r' || data[2] == 'R') {
-
- i = 3
- for i < len(data) && data[i] != '>' {
- i++
- }
-
- if i+1 < len(data) {
- i++
- j = parser.isEmpty(data[i:])
- if j > 0 {
- size := i + j
- if doRender {
- // trim newlines
- end := size
- for end > 0 && data[end-1] == '\n' {
- end--
- }
- parser.r.BlockHtml(out, data[:end])
- }
- return size
- }
- }
+ // check for an
tag
+ if size := parser.blockHtmlHr(out, data, doRender); size > 0 {
+ return size
}
// no special case recognized
@@ -302,13 +264,40 @@ func (parser *Parser) blockHtml(out *bytes.Buffer, data []byte, doRender bool) i
}
// look for an unindented matching closing tag
- // followed by a blank line
- i = 1
+ // followed by a blank line
found := false
+ /*
+ closetag := []byte("\n")
+ j = len(curtag) + 1
+ for !found {
+ // scan for a closing tag at the beginning of a line
+ if skip := bytes.Index(data[j:], closetag); skip >= 0 {
+ j += skip + len(closetag)
+ } else {
+ break
+ }
+
+ // see if it is the only thing on the line
+ if skip := parser.isEmpty(data[j:]); skip > 0 {
+ // see if it is followed by a blank line/eof
+ j += skip
+ if j >= len(data) {
+ found = true
+ i = j
+ } else {
+ if skip := parser.isEmpty(data[j:]); skip > 0 {
+ j += skip
+ found = true
+ i = j
+ }
+ }
+ }
+ }
+ */
// if not found, try a second pass looking for indented match
// but not if tag is "ins" or "del" (following original Markdown.pl)
- if curtag != "ins" && curtag != "del" {
+ if !found && curtag != "ins" && curtag != "del" {
i = 1
for i < len(data) {
i++
@@ -347,13 +336,80 @@ func (parser *Parser) blockHtml(out *bytes.Buffer, data []byte, doRender bool) i
return i
}
-func (parser *Parser) blockHtmlFindTag(data []byte) (string, bool) {
- i := 0
- for i < len(data) && isalnum(data[i]) {
+// HTML comment, lax form
+func (parser *Parser) blockHtmlComment(out *bytes.Buffer, data []byte, doRender bool) int {
+ if data[0] != '<' || data[1] != '!' || data[2] != '-' || data[3] != '-' {
+ return 0
+ }
+
+ i := 5
+
+ // scan for an end-of-comment marker, across lines if necessary
+ for i < len(data) && !(data[i-2] == '-' && data[i-1] == '-' && data[i] == '>') {
i++
}
+ i++
+
+ // no end-of-comment marker
if i >= len(data) {
- return "", false
+ return 0
+ }
+
+ // needs to end with a blank line
+ if j := parser.isEmpty(data[i:]); j > 0 {
+ size := i + j
+ if doRender {
+ // trim trailing newlines
+ end := size
+ for end > 0 && data[end-1] == '\n' {
+ end--
+ }
+ parser.r.BlockHtml(out, data[:end])
+ }
+ return size
+ }
+
+ return 0
+}
+
+// HR, which is the only self-closing block tag considered
+func (parser *Parser) blockHtmlHr(out *bytes.Buffer, data []byte, doRender bool) int {
+ if data[0] != '<' || (data[1] != 'h' && data[1] != 'H') || (data[2] != 'r' && data[2] != 'R') {
+ return 0
+ }
+ if data[3] != ' ' && data[3] != '\t' && data[3] != '/' && data[3] != '>' {
+ // not an
tag after all; at least not a valid one
+ return 0
+ }
+
+ i := 3
+ for data[i] != '>' && data[i] != '\n' {
+ i++
+ }
+
+ if data[i] == '>' {
+ i++
+ if j := parser.isEmpty(data[i:]); j > 0 {
+ size := i + j
+ if doRender {
+ // trim newlines
+ end := size
+ for end > 0 && data[end-1] == '\n' {
+ end--
+ }
+ parser.r.BlockHtml(out, data[:end])
+ }
+ return size
+ }
+ }
+
+ return 0
+}
+
+func (parser *Parser) blockHtmlFindTag(data []byte) (string, bool) {
+ i := 0
+ for isalnum(data[i]) {
+ i++
}
key := string(data[:i])
if blockTags[key] {
@@ -366,40 +422,43 @@ func (parser *Parser) blockHtmlFindEnd(tag string, data []byte) int {
// assume data[0] == '<' && data[1] == '/' already tested
// check if tag is a match
- if len(data) < len(tag)+3 || data[len(tag)+2] != '>' ||
- bytes.Compare(data[2:2+len(tag)], []byte(tag)) != 0 {
+ closetag := []byte("")
+ if !bytes.HasPrefix(data, closetag) {
+ return 0
+ }
+ i := len(closetag)
+
+ // check that the rest of the line is blank
+ skip := 0
+ if skip = parser.isEmpty(data[i:]); skip == 0 {
+ return 0
+ }
+ i += skip
+ skip = 0
+
+ if i >= len(data) {
+ return i
+ }
+
+ if parser.flags&EXTENSION_LAX_HTML_BLOCKS != 0 {
+ return i
+ }
+ if skip = parser.isEmpty(data[i:]); skip == 0 {
+ // following line must be blank
return 0
}
- // check for blank line/eof after the closing tag
- i := len(tag) + 3
- w := 0
- if i < len(data) {
- if w = parser.isEmpty(data[i:]); w == 0 {
- return 0 // non-blank after tag
- }
- }
- i += w
- w = 0
-
- if parser.flags&EXTENSION_LAX_HTML_BLOCKS != 0 {
- if i < len(data) {
- w = parser.isEmpty(data[i:])
- }
- } else {
- if i < len(data) {
- if w = parser.isEmpty(data[i:]); w == 0 {
- return 0 // non-blank line after tag line
- }
- }
- }
-
- return i + w
+ return i + skip
}
func (parser *Parser) isEmpty(data []byte) int {
+ // it is okay to call isEmpty on an empty buffer
+ if len(data) == 0 {
+ return 0
+ }
+
var i int
- for i = 0; i < len(data) && data[i] != '\n'; i++ {
+ for i = 0; data[i] != '\n'; i++ {
if data[i] != ' ' && data[i] != '\t' {
return 0
}
@@ -408,10 +467,6 @@ func (parser *Parser) isEmpty(data []byte) int {
}
func (parser *Parser) isHRule(data []byte) bool {
- // skip initial spaces
- if len(data) < 3 {
- return false
- }
i := 0
// skip up to three spaces
@@ -420,14 +475,14 @@ func (parser *Parser) isHRule(data []byte) bool {
}
// look at the hrule char
- if i+2 >= len(data) || (data[i] != '*' && data[i] != '-' && data[i] != '_') {
+ if data[i] != '*' && data[i] != '-' && data[i] != '_' {
return false
}
c := data[i]
// the whole line must be the char or whitespace
n := 0
- for i < len(data) && data[i] != '\n' {
+ for data[i] != '\n' {
switch {
case data[i] == c:
n++
@@ -444,29 +499,20 @@ func (parser *Parser) isFencedCode(data []byte, syntax **string, oldmarker strin
i, size := 0, 0
skip = 0
- // skip initial spaces
- if len(data) < 3 {
- return
- }
- if data[0] == ' ' {
+ // skip up to three spaces
+ for i < 3 && data[i] == ' ' {
i++
- if data[1] == ' ' {
- i++
- if data[2] == ' ' {
- i++
- }
- }
}
// check for the marker characters: ~ or `
- if i+2 >= len(data) || !(data[i] == '~' || data[i] == '`') {
+ if data[i] != '~' && data[i] != '`' {
return
}
c := data[i]
// the whole line must be the same char or whitespace
- for i < len(data) && data[i] == c {
+ for data[i] == c {
size++
i++
}
@@ -485,22 +531,22 @@ func (parser *Parser) isFencedCode(data []byte, syntax **string, oldmarker strin
if syntax != nil {
syn := 0
- for i < len(data) && (data[i] == ' ' || data[i] == '\t') {
+ for data[i] == ' ' || data[i] == '\t' {
i++
}
syntaxStart := i
- if i < len(data) && data[i] == '{' {
+ if data[i] == '{' {
i++
syntaxStart++
- for i < len(data) && data[i] != '}' && data[i] != '\n' {
+ for data[i] != '}' && data[i] != '\n' {
syn++
i++
}
- if i == len(data) || data[i] != '}' {
+ if data[i] != '}' {
return
}
@@ -517,7 +563,7 @@ func (parser *Parser) isFencedCode(data []byte, syntax **string, oldmarker strin
i++
} else {
- for i < len(data) && !isspace(data[i]) {
+ for !isspace(data[i]) {
syn++
i++
}
@@ -527,7 +573,7 @@ func (parser *Parser) isFencedCode(data []byte, syntax **string, oldmarker strin
*syntax = &language
}
- for ; i < len(data) && data[i] != '\n'; i++ {
+ for ; data[i] != '\n'; i++ {
if !isspace(data[i]) {
return
}
@@ -756,11 +802,11 @@ func (parser *Parser) blockTableRow(out *bytes.Buffer, data []byte, columns int,
// returns blockquote prefix length
func (parser *Parser) blockQuotePrefix(data []byte) int {
i := 0
- for i < len(data) && i < 3 && data[i] == ' ' {
+ for i < 3 && data[i] == ' ' {
i++
}
- if i < len(data) && data[i] == '>' {
- if i+1 < len(data) && (data[i+1] == ' ' || data[i+1] == '\t') {
+ if data[i] == '>' {
+ if data[i+1] == ' ' || data[i+1] == '\t' {
return i + 2
}
return i + 1
@@ -770,17 +816,18 @@ func (parser *Parser) blockQuotePrefix(data []byte) int {
// parse a blockquote fragment
func (parser *Parser) blockQuote(out *bytes.Buffer, data []byte) int {
- var block bytes.Buffer
- var work bytes.Buffer
+ var raw bytes.Buffer
beg, end := 0, 0
for beg < len(data) {
- for end = beg + 1; end < len(data) && data[end-1] != '\n'; end++ {
+ for end = beg + 1; data[end-1] != '\n'; end++ {
}
if pre := parser.blockQuotePrefix(data[beg:]); pre > 0 {
- beg += pre // skip prefix
+ // string the prefix
+ beg += pre
} else {
- // empty line followed by non-quote line
+ // blockquote ends with at least one blank line
+ // followed by something without a blockquote prefix
if parser.isEmpty(data[beg:]) > 0 &&
(end >= len(data) ||
(parser.blockQuotePrefix(data[end:]) == 0 && parser.isEmpty(data[end:]) == 0)) {
@@ -788,14 +835,14 @@ func (parser *Parser) blockQuote(out *bytes.Buffer, data []byte) int {
}
}
- if beg < end { // copy into the in-place working buffer
- work.Write(data[beg:end])
- }
+ // this line is part of the blockquote
+ raw.Write(data[beg:end])
beg = end
}
- parser.parseBlock(&block, work.Bytes())
- parser.r.BlockQuote(out, block.Bytes())
+ var cooked bytes.Buffer
+ parser.parseBlock(&cooked, raw.Bytes())
+ parser.r.BlockQuote(out, cooked.Bytes())
return end
}