251
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// |
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// Blackfriday Markdown Processor |
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// Available at http://github.com/russross/blackfriday |
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// |
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// Copyright © 2011 Russ Ross <russ@russross.com>. |
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// Distributed under the Simplified BSD License. |
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// See README.md for details. |
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// |
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// |
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// Functions to parse inline elements. |
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// |
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|
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package blackfriday |
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|
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import ( |
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"bytes" |
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"regexp" |
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"strconv" |
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) |
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|
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var ( |
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urlRe = `((https?|ftp):\/\/|\/)[-A-Za-z0-9+&@#\/%?=~_|!:,.;\(\)]+` |
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anchorRe = regexp.MustCompile(`^(<a\shref="` + urlRe + `"(\stitle="[^"<>]+")?\s?>` + urlRe + `<\/a>)`) |
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) |
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|
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// Functions to parse text within a block |
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// Each function returns the number of chars taken care of |
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// data is the complete block being rendered |
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// offset is the number of valid chars before the current cursor |
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|
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func (p *parser) inline(out *bytes.Buffer, data []byte) { |
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// this is called recursively: enforce a maximum depth |
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if p.nesting >= p.maxNesting { |
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return |
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} |
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p.nesting++ |
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|
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i, end := 0, 0 |
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for i < len(data) { |
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// copy inactive chars into the output |
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for end < len(data) && p.inlineCallback[data[end]] == nil { |
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end++ |
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} |
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|
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p.r.NormalText(out, data[i:end]) |
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|
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if end >= len(data) { |
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break |
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} |
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i = end |
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|
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// call the trigger |
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handler := p.inlineCallback[data[end]] |
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if consumed := handler(p, out, data, i); consumed == 0 { |
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// no action from the callback; buffer the byte for later |
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end = i + 1 |
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} else { |
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// skip past whatever the callback used |
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i += consumed |
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end = i |
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} |
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} |
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|
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p.nesting-- |
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} |
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|
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// single and double emphasis parsing |
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func emphasis(p *parser, out *bytes.Buffer, data []byte, offset int) int { |
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data = data[offset:] |
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c := data[0] |
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ret := 0 |
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|
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if len(data) > 2 && data[1] != c { |
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// whitespace cannot follow an opening emphasis; |
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// strikethrough only takes two characters '~~' |
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if c == '~' || isspace(data[1]) { |
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return 0 |
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} |
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if ret = helperEmphasis(p, out, data[1:], c); ret == 0 { |
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return 0 |
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} |
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|
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return ret + 1 |
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} |
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|
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if len(data) > 3 && data[1] == c && data[2] != c { |
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if isspace(data[2]) { |
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return 0 |
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} |
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if ret = helperDoubleEmphasis(p, out, data[2:], c); ret == 0 { |
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return 0 |
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} |
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return ret + 2 |
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} |
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|
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if len(data) > 4 && data[1] == c && data[2] == c && data[3] != c { |
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if c == '~' || isspace(data[3]) { |
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return 0 |
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} |
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if ret = helperTripleEmphasis(p, out, data, 3, c); ret == 0 { |
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return 0 |
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} |
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return ret + 3 |
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} |
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return 0 |
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} |
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|
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func codeSpan(p *parser, out *bytes.Buffer, data []byte, offset int) int { |
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data = data[offset:] |
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nb := 0 |
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|
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// count the number of backticks in the delimiter |
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for nb < len(data) && data[nb] == '`' { |
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nb++ |
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} |
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|
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// find the next delimiter |
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i, end := 0, 0 |
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for end = nb; end < len(data) && i < nb; end++ { |
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if data[end] == '`' { |
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i++ |
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} else { |
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i = 0 |
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} |
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} |
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|
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// no matching delimiter? |
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if i < nb && end >= len(data) { |
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return 0 |
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} |
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|
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// trim outside whitespace |
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fBegin := nb |
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for fBegin < end && data[fBegin] == ' ' { |
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fBegin++ |
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} |
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|
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fEnd := end - nb |
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for fEnd > fBegin && data[fEnd-1] == ' ' { |
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fEnd-- |
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} |
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|
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// render the code span |
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if fBegin != fEnd { |
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p.r.CodeSpan(out, data[fBegin:fEnd]) |
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} |
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return end |
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} |
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// newline preceded by two spaces becomes <br> |
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// newline without two spaces works when EXTENSION_HARD_LINE_BREAK is enabled |
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func lineBreak(p *parser, out *bytes.Buffer, data []byte, offset int) int { |
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// remove trailing spaces from out |
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outBytes := out.Bytes() |
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end := len(outBytes) |
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eol := end |
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for eol > 0 && outBytes[eol-1] == ' ' { |
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eol-- |
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} |
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out.Truncate(eol) |
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precededByTwoSpaces := offset >= 2 && data[offset-2] == ' ' && data[offset-1] == ' ' |
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precededByBackslash := offset >= 1 && data[offset-1] == '\\' // see http://spec.commonmark.org/0.18/#example-527 |
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precededByBackslash = precededByBackslash && p.flags&EXTENSION_BACKSLASH_LINE_BREAK != 0 |
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|
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if p.flags&EXTENSION_JOIN_LINES != 0 { |
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return 1 |
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} |
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|
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// should there be a hard line break here? |
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if p.flags&EXTENSION_HARD_LINE_BREAK == 0 && !precededByTwoSpaces && !precededByBackslash { |
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return 0 |
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} |
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|
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if precededByBackslash && eol > 0 { |
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out.Truncate(eol - 1) |
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} |
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p.r.LineBreak(out) |
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return 1 |
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} |
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|
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type linkType int |
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|
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const ( |
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linkNormal linkType = iota |
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linkImg |
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linkDeferredFootnote |
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linkInlineFootnote |
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) |
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|
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func isReferenceStyleLink(data []byte, pos int, t linkType) bool { |
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if t == linkDeferredFootnote { |
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return false |
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} |
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return pos < len(data)-1 && data[pos] == '[' && data[pos+1] != '^' |
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} |
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|
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// '[': parse a link or an image or a footnote |
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func link(p *parser, out *bytes.Buffer, data []byte, offset int) int { |
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// no links allowed inside regular links, footnote, and deferred footnotes |
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if p.insideLink && (offset > 0 && data[offset-1] == '[' || len(data)-1 > offset && data[offset+1] == '^') { |
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return 0 |
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} |
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var t linkType |
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switch { |
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// special case: ![^text] == deferred footnote (that follows something with |
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// an exclamation point) |
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case p.flags&EXTENSION_FOOTNOTES != 0 && len(data)-1 > offset && data[offset+1] == '^': |
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t = linkDeferredFootnote |
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// ![alt] == image |
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case offset > 0 && data[offset-1] == '!': |
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t = linkImg |
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// ^[text] == inline footnote |
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// [^refId] == deferred footnote |
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case p.flags&EXTENSION_FOOTNOTES != 0: |
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if offset > 0 && data[offset-1] == '^' { |
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t = linkInlineFootnote |
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} else if len(data)-1 > offset && data[offset+1] == '^' { |
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t = linkDeferredFootnote |
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} |
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// [text] == regular link |
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default: |
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t = linkNormal |
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} |
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data = data[offset:] |
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|
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var ( |
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i = 1 |
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noteId int |
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title, link, altContent []byte |
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textHasNl = false |
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) |
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if t == linkDeferredFootnote { |
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i++ |
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} |
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brace := 0 |
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// look for the matching closing bracket |
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for level := 1; level > 0 && i < len(data); i++ { |
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switch { |
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case data[i] == '\n': |
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textHasNl = true |
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|
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case data[i-1] == '\\': |
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continue |
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|
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case data[i] == '[': |
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level++ |
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case data[i] == ']': |
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level-- |
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if level <= 0 { |
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i-- // compensate for extra i++ in for loop |
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} |
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} |
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} |
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268 |
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if i >= len(data) { |
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return 0 |
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} |
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txtE := i |
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i++ |
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|
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// skip any amount of whitespace or newline |
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// (this is much more lax than original markdown syntax) |
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for i < len(data) && isspace(data[i]) { |
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i++ |
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} |
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281 |
|
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switch { |
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// inline style link |
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case i < len(data) && data[i] == '(': |
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// skip initial whitespace |
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i++ |
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287 |
|
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for i < len(data) && isspace(data[i]) { |
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i++ |
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} |
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291 |
|
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linkB := i |
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293 |
|
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// look for link end: ' " ), check for new opening braces and take this |
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// into account, this may lead for overshooting and probably will require |
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// some fine-tuning. |
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297 |
findlinkend: |
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298 |
for i < len(data) { |
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switch { |
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300 |
case data[i] == '\\': |
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i += 2 |
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302 |
|
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case data[i] == '(': |
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brace++ |
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305 |
i++ |
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306 |
|
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307 |
case data[i] == ')': |
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if brace <= 0 { |
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break findlinkend |
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} |
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311 |
brace-- |
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312 |
i++ |
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313 |
|
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case data[i] == '\'' || data[i] == '"': |
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break findlinkend |
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316 |
|
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default: |
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318 |
i++ |
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} |
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} |
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321 |
|
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if i >= len(data) { |
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return 0 |
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} |
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linkE := i |
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326 |
|
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// look for title end if present |
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titleB, titleE := 0, 0 |
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if data[i] == '\'' || data[i] == '"' { |
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i++ |
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331 |
titleB = i |
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332 |
|
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findtitleend: |
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for i < len(data) { |
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switch { |
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336 |
case data[i] == '\\': |
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i += 2 |
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338 |
|
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case data[i] == ')': |
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break findtitleend |
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341 |
|
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default: |
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343 |
i++ |
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344 |
} |
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} |
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346 |
|
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if i >= len(data) { |
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return 0 |
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349 |
} |
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350 |
|
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// skip whitespace after title |
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352 |
titleE = i - 1 |
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353 |
for titleE > titleB && isspace(data[titleE]) { |
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titleE-- |
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} |
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356 |
|
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357 |
// check for closing quote presence |
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358 |
if data[titleE] != '\'' && data[titleE] != '"' { |
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359 |
titleB, titleE = 0, 0 |
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360 |
linkE = i |
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361 |
} |
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362 |
} |
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363 |
|
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364 |
// remove whitespace at the end of the link |
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365 |
for linkE > linkB && isspace(data[linkE-1]) { |
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366 |
linkE-- |
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367 |
} |
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368 |
|
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369 |
// remove optional angle brackets around the link |
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370 |
if data[linkB] == '<' { |
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371 |
linkB++ |
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372 |
} |
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373 |
if data[linkE-1] == '>' { |
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374 |
linkE-- |
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375 |
} |
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376 |
|
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377 |
// build escaped link and title |
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378 |
if linkE > linkB { |
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link = data[linkB:linkE] |
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380 |
} |
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381 |
|
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382 |
if titleE > titleB { |
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383 |
title = data[titleB:titleE] |
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384 |
} |
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385 |
|
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386 |
i++ |
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387 |
|
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388 |
// reference style link |
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389 |
case isReferenceStyleLink(data, i, t): |
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390 |
var id []byte |
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391 |
altContentConsidered := false |
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392 |
|
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393 |
// look for the id |
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394 |
i++ |
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395 |
linkB := i |
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396 |
for i < len(data) && data[i] != ']' { |
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397 |
i++ |
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398 |
} |
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399 |
if i >= len(data) { |
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400 |
return 0 |
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401 |
} |
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402 |
linkE := i |
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403 |
|
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404 |
// find the reference |
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405 |
if linkB == linkE { |
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406 |
if textHasNl { |
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407 |
var b bytes.Buffer |
|
408 |
|
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409 |
for j := 1; j < txtE; j++ { |
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410 |
switch { |
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411 |
case data[j] != '\n': |
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412 |
b.WriteByte(data[j]) |
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413 |
case data[j-1] != ' ': |
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414 |
b.WriteByte(' ') |
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415 |
} |
|
416 |
} |
|
417 |
|
|
418 |
id = b.Bytes() |
|
419 |
} else { |
|
420 |
id = data[1:txtE] |
|
421 |
altContentConsidered = true |
|
422 |
} |
|
423 |
} else { |
|
424 |
id = data[linkB:linkE] |
|
425 |
} |
|
426 |
|
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427 |
// find the reference with matching id |
|
428 |
lr, ok := p.getRef(string(id)) |
|
429 |
if !ok { |
|
430 |
return 0 |
|
431 |
} |
|
432 |
|
|
433 |
// keep link and title from reference |
|
434 |
link = lr.link |
|
435 |
title = lr.title |
|
436 |
if altContentConsidered { |
|
437 |
altContent = lr.text |
|
438 |
} |
|
439 |
i++ |
|
440 |
|
|
441 |
// shortcut reference style link or reference or inline footnote |
|
442 |
default: |
|
443 |
var id []byte |
|
444 |
|
|
445 |
// craft the id |
|
446 |
if textHasNl { |
|
447 |
var b bytes.Buffer |
|
448 |
|
|
449 |
for j := 1; j < txtE; j++ { |
|
450 |
switch { |
|
451 |
case data[j] != '\n': |
|
452 |
b.WriteByte(data[j]) |
|
453 |
case data[j-1] != ' ': |
|
454 |
b.WriteByte(' ') |
|
455 |
} |
|
456 |
} |
|
457 |
|
|
458 |
id = b.Bytes() |
|
459 |
} else { |
|
460 |
if t == linkDeferredFootnote { |
|
461 |
id = data[2:txtE] // get rid of the ^ |
|
462 |
} else { |
|
463 |
id = data[1:txtE] |
|
464 |
} |
|
465 |
} |
|
466 |
|
|
467 |
if t == linkInlineFootnote { |
|
468 |
// create a new reference |
|
469 |
noteId = len(p.notes) + 1 |
|
470 |
|
|
471 |
var fragment []byte |
|
472 |
if len(id) > 0 { |
|
473 |
if len(id) < 16 { |
|
474 |
fragment = make([]byte, len(id)) |
|
475 |
} else { |
|
476 |
fragment = make([]byte, 16) |
|
477 |
} |
|
478 |
copy(fragment, slugify(id)) |
|
479 |
} else { |
|
480 |
fragment = append([]byte("footnote-"), []byte(strconv.Itoa(noteId))...) |
|
481 |
} |
|
482 |
|
|
483 |
ref := &reference{ |
|
484 |
noteId: noteId, |
|
485 |
hasBlock: false, |
|
486 |
link: fragment, |
|
487 |
title: id, |
|
488 |
} |
|
489 |
|
|
490 |
p.notes = append(p.notes, ref) |
|
491 |
p.notesRecord[string(ref.link)] = struct{}{} |
|
492 |
|
|
493 |
link = ref.link |
|
494 |
title = ref.title |
|
495 |
} else { |
|
496 |
// find the reference with matching id |
|
497 |
lr, ok := p.getRef(string(id)) |
|
498 |
if !ok { |
|
499 |
return 0 |
|
500 |
} |
|
501 |
|
|
502 |
if t == linkDeferredFootnote && !p.isFootnote(lr) { |
|
503 |
lr.noteId = len(p.notes) + 1 |
|
504 |
p.notes = append(p.notes, lr) |
|
505 |
p.notesRecord[string(lr.link)] = struct{}{} |
|
506 |
} |
|
507 |
|
|
508 |
// keep link and title from reference |
|
509 |
link = lr.link |
|
510 |
// if inline footnote, title == footnote contents |
|
511 |
title = lr.title |
|
512 |
noteId = lr.noteId |
|
513 |
} |
|
514 |
|
|
515 |
// rewind the whitespace |
|
516 |
i = txtE + 1 |
|
517 |
} |
|
518 |
|
|
519 |
// build content: img alt is escaped, link content is parsed |
|
520 |
var content bytes.Buffer |
|
521 |
if txtE > 1 { |
|
522 |
if t == linkImg { |
|
523 |
content.Write(data[1:txtE]) |
|
524 |
} else { |
|
525 |
// links cannot contain other links, so turn off link parsing temporarily |
|
526 |
insideLink := p.insideLink |
|
527 |
p.insideLink = true |
|
528 |
p.inline(&content, data[1:txtE]) |
|
529 |
p.insideLink = insideLink |
|
530 |
} |
|
531 |
} |
|
532 |
|
|
533 |
var uLink []byte |
|
534 |
if t == linkNormal || t == linkImg { |
|
535 |
if len(link) > 0 { |
|
536 |
var uLinkBuf bytes.Buffer |
|
537 |
unescapeText(&uLinkBuf, link) |
|
538 |
uLink = uLinkBuf.Bytes() |
|
539 |
} |
|
540 |
|
|
541 |
// links need something to click on and somewhere to go |
|
542 |
if len(uLink) == 0 || (t == linkNormal && content.Len() == 0) { |
|
543 |
return 0 |
|
544 |
} |
|
545 |
} |
|
546 |
|
|
547 |
// call the relevant rendering function |
|
548 |
switch t { |
|
549 |
case linkNormal: |
|
550 |
if len(altContent) > 0 { |
|
551 |
p.r.Link(out, uLink, title, altContent) |
|
552 |
} else { |
|
553 |
p.r.Link(out, uLink, title, content.Bytes()) |
|
554 |
} |
|
555 |
|
|
556 |
case linkImg: |
|
557 |
outSize := out.Len() |
|
558 |
outBytes := out.Bytes() |
|
559 |
if outSize > 0 && outBytes[outSize-1] == '!' { |
|
560 |
out.Truncate(outSize - 1) |
|
561 |
} |
|
562 |
|
|
563 |
p.r.Image(out, uLink, title, content.Bytes()) |
|
564 |
|
|
565 |
case linkInlineFootnote: |
|
566 |
outSize := out.Len() |
|
567 |
outBytes := out.Bytes() |
|
568 |
if outSize > 0 && outBytes[outSize-1] == '^' { |
|
569 |
out.Truncate(outSize - 1) |
|
570 |
} |
|
571 |
|
|
572 |
p.r.FootnoteRef(out, link, noteId) |
|
573 |
|
|
574 |
case linkDeferredFootnote: |
|
575 |
p.r.FootnoteRef(out, link, noteId) |
|
576 |
|
|
577 |
default: |
|
578 |
return 0 |
|
579 |
} |
|
580 |
|
|
581 |
return i |
|
582 |
} |
|
583 |
|
|
584 |
func (p *parser) inlineHTMLComment(out *bytes.Buffer, data []byte) int { |
|
585 |
if len(data) < 5 { |
|
586 |
return 0 |
|
587 |
} |
|
588 |
if data[0] != '<' || data[1] != '!' || data[2] != '-' || data[3] != '-' { |
|
589 |
return 0 |
|
590 |
} |
|
591 |
i := 5 |
|
592 |
// scan for an end-of-comment marker, across lines if necessary |
|
593 |
for i < len(data) && !(data[i-2] == '-' && data[i-1] == '-' && data[i] == '>') { |
|
594 |
i++ |
|
595 |
} |
|
596 |
// no end-of-comment marker |
|
597 |
if i >= len(data) { |
|
598 |
return 0 |
|
599 |
} |
|
600 |
return i + 1 |
|
601 |
} |
|
602 |
|
|
603 |
// '<' when tags or autolinks are allowed |
|
604 |
func leftAngle(p *parser, out *bytes.Buffer, data []byte, offset int) int { |
|
605 |
data = data[offset:] |
|
606 |
altype := LINK_TYPE_NOT_AUTOLINK |
|
607 |
end := tagLength(data, &altype) |
|
608 |
if size := p.inlineHTMLComment(out, data); size > 0 { |
|
609 |
end = size |
|
610 |
} |
|
611 |
if end > 2 { |
|
612 |
if altype != LINK_TYPE_NOT_AUTOLINK { |
|
613 |
var uLink bytes.Buffer |
|
614 |
unescapeText(&uLink, data[1:end+1-2]) |
|
615 |
if uLink.Len() > 0 { |
|
616 |
p.r.AutoLink(out, uLink.Bytes(), altype) |
|
617 |
} |
|
618 |
} else { |
|
619 |
p.r.RawHtmlTag(out, data[:end]) |
|
620 |
} |
|
621 |
} |
|
622 |
|
|
623 |
return end |
|
624 |
} |
|
625 |
|
|
626 |
// '\\' backslash escape |
|
627 |
var escapeChars = []byte("\\`*_{}[]()#+-.!:|&<>~") |
|
628 |
|
|
629 |
func escape(p *parser, out *bytes.Buffer, data []byte, offset int) int { |
|
630 |
data = data[offset:] |
|
631 |
|
|
632 |
if len(data) > 1 { |
|
633 |
if bytes.IndexByte(escapeChars, data[1]) < 0 { |
|
634 |
return 0 |
|
635 |
} |
|
636 |
|
|
637 |
p.r.NormalText(out, data[1:2]) |
|
638 |
} |
|
639 |
|
|
640 |
return 2 |
|
641 |
} |
|
642 |
|
|
643 |
func unescapeText(ob *bytes.Buffer, src []byte) { |
|
644 |
i := 0 |
|
645 |
for i < len(src) { |
|
646 |
org := i |
|
647 |
for i < len(src) && src[i] != '\\' { |
|
648 |
i++ |
|
649 |
} |
|
650 |
|
|
651 |
if i > org { |
|
652 |
ob.Write(src[org:i]) |
|
653 |
} |
|
654 |
|
|
655 |
if i+1 >= len(src) { |
|
656 |
break |
|
657 |
} |
|
658 |
|
|
659 |
ob.WriteByte(src[i+1]) |
|
660 |
i += 2 |
|
661 |
} |
|
662 |
} |
|
663 |
|
|
664 |
// '&' escaped when it doesn't belong to an entity |
|
665 |
// valid entities are assumed to be anything matching &#?[A-Za-z0-9]+; |
|
666 |
func entity(p *parser, out *bytes.Buffer, data []byte, offset int) int { |
|
667 |
data = data[offset:] |
|
668 |
|
|
669 |
end := 1 |
|
670 |
|
|
671 |
if end < len(data) && data[end] == '#' { |
|
672 |
end++ |
|
673 |
} |
|
674 |
|
|
675 |
for end < len(data) && isalnum(data[end]) { |
|
676 |
end++ |
|
677 |
} |
|
678 |
|
|
679 |
if end < len(data) && data[end] == ';' { |
|
680 |
end++ // real entity |
|
681 |
} else { |
|
682 |
return 0 // lone '&' |
|
683 |
} |
|
684 |
|
|
685 |
p.r.Entity(out, data[:end]) |
|
686 |
|
|
687 |
return end |
|
688 |
} |
|
689 |
|
|
690 |
func linkEndsWithEntity(data []byte, linkEnd int) bool { |
|
691 |
entityRanges := htmlEntity.FindAllIndex(data[:linkEnd], -1) |
|
692 |
return entityRanges != nil && entityRanges[len(entityRanges)-1][1] == linkEnd |
|
693 |
} |
|
694 |
|
|
695 |
func autoLink(p *parser, out *bytes.Buffer, data []byte, offset int) int { |
|
696 |
// quick check to rule out most false hits on ':' |
|
697 |
if p.insideLink || len(data) < offset+3 || data[offset+1] != '/' || data[offset+2] != '/' { |
|
698 |
return 0 |
|
699 |
} |
|
700 |
|
|
701 |
// Now a more expensive check to see if we're not inside an anchor element |
|
702 |
anchorStart := offset |
|
703 |
offsetFromAnchor := 0 |
|
704 |
for anchorStart > 0 && data[anchorStart] != '<' { |
|
705 |
anchorStart-- |
|
706 |
offsetFromAnchor++ |
|
707 |
} |
|
708 |
|
|
709 |
anchorStr := anchorRe.Find(data[anchorStart:]) |
|
710 |
if anchorStr != nil { |
|
711 |
out.Write(anchorStr[offsetFromAnchor:]) |
|
712 |
return len(anchorStr) - offsetFromAnchor |
|
713 |
} |
|
714 |
|
|
715 |
// scan backward for a word boundary |
|
716 |
rewind := 0 |
|
717 |
for offset-rewind > 0 && rewind <= 7 && isletter(data[offset-rewind-1]) { |
|
718 |
rewind++ |
|
719 |
} |
|
720 |
if rewind > 6 { // longest supported protocol is "mailto" which has 6 letters |
|
721 |
return 0 |
|
722 |
} |
|
723 |
|
|
724 |
origData := data |
|
725 |
data = data[offset-rewind:] |
|
726 |
|
|
727 |
if !isSafeLink(data) { |
|
728 |
return 0 |
|
729 |
} |
|
730 |
|
|
731 |
linkEnd := 0 |
|
732 |
for linkEnd < len(data) && !isEndOfLink(data[linkEnd]) { |
|
733 |
linkEnd++ |
|
734 |
} |
|
735 |
|
|
736 |
// Skip punctuation at the end of the link |
|
737 |
if (data[linkEnd-1] == '.' || data[linkEnd-1] == ',') && data[linkEnd-2] != '\\' { |
|
738 |
linkEnd-- |
|
739 |
} |
|
740 |
|
|
741 |
// But don't skip semicolon if it's a part of escaped entity: |
|
742 |
if data[linkEnd-1] == ';' && data[linkEnd-2] != '\\' && !linkEndsWithEntity(data, linkEnd) { |
|
743 |
linkEnd-- |
|
744 |
} |
|
745 |
|
|
746 |
// See if the link finishes with a punctuation sign that can be closed. |
|
747 |
var copen byte |
|
748 |
switch data[linkEnd-1] { |
|
749 |
case '"': |
|
750 |
copen = '"' |
|
751 |
case '\'': |
|
752 |
copen = '\'' |
|
753 |
case ')': |
|
754 |
copen = '(' |
|
755 |
case ']': |
|
756 |
copen = '[' |
|
757 |
case '}': |
|
758 |
copen = '{' |
|
759 |
default: |
|
760 |
copen = 0 |
|
761 |
} |
|
762 |
|
|
763 |
if copen != 0 { |
|
764 |
bufEnd := offset - rewind + linkEnd - 2 |
|
765 |
|
|
766 |
openDelim := 1 |
|
767 |
|
|
768 |
/* Try to close the final punctuation sign in this same line; |
|
769 |
* if we managed to close it outside of the URL, that means that it's |
|
770 |
* not part of the URL. If it closes inside the URL, that means it |
|
771 |
* is part of the URL. |
|
772 |
* |
|
773 |
* Examples: |
|
774 |
* |
|
775 |
* foo http://www.pokemon.com/Pikachu_(Electric) bar |
|
776 |
* => http://www.pokemon.com/Pikachu_(Electric) |
|
777 |
* |
|
778 |
* foo (http://www.pokemon.com/Pikachu_(Electric)) bar |
|
779 |
* => http://www.pokemon.com/Pikachu_(Electric) |
|
780 |
* |
|
781 |
* foo http://www.pokemon.com/Pikachu_(Electric)) bar |
|
782 |
* => http://www.pokemon.com/Pikachu_(Electric)) |
|
783 |
* |
|
784 |
* (foo http://www.pokemon.com/Pikachu_(Electric)) bar |
|
785 |
* => foo http://www.pokemon.com/Pikachu_(Electric) |
|
786 |
*/ |
|
787 |
|
|
788 |
for bufEnd >= 0 && origData[bufEnd] != '\n' && openDelim != 0 { |
|
789 |
if origData[bufEnd] == data[linkEnd-1] { |
|
790 |
openDelim++ |
|
791 |
} |
|
792 |
|
|
793 |
if origData[bufEnd] == copen { |
|
794 |
openDelim-- |
|
795 |
} |
|
796 |
|
|
797 |
bufEnd-- |
|
798 |
} |
|
799 |
|
|
800 |
if openDelim == 0 { |
|
801 |
linkEnd-- |
|
802 |
} |
|
803 |
} |
|
804 |
|
|
805 |
// we were triggered on the ':', so we need to rewind the output a bit |
|
806 |
if out.Len() >= rewind { |
|
807 |
out.Truncate(len(out.Bytes()) - rewind) |
|
808 |
} |
|
809 |
|
|
810 |
var uLink bytes.Buffer |
|
811 |
unescapeText(&uLink, data[:linkEnd]) |
|
812 |
|
|
813 |
if uLink.Len() > 0 { |
|
814 |
p.r.AutoLink(out, uLink.Bytes(), LINK_TYPE_NORMAL) |
|
815 |
} |
|
816 |
|
|
817 |
return linkEnd - rewind |
|
818 |
} |
|
819 |
|
|
820 |
func isEndOfLink(char byte) bool { |
|
821 |
return isspace(char) || char == '<' |
|
822 |
} |
|
823 |
|
|
824 |
var validUris = [][]byte{[]byte("http://"), []byte("https://"), []byte("ftp://"), []byte("mailto://")} |
|
825 |
var validPaths = [][]byte{[]byte("/"), []byte("./"), []byte("../")} |
|
826 |
|
|
827 |
func isSafeLink(link []byte) bool { |
|
828 |
for _, path := range validPaths { |
|
829 |
if len(link) >= len(path) && bytes.Equal(link[:len(path)], path) { |
|
830 |
if len(link) == len(path) { |
|
831 |
return true |
|
832 |
} else if isalnum(link[len(path)]) { |
|
833 |
return true |
|
834 |
} |
|
835 |
} |
|
836 |
} |
|
837 |
|
|
838 |
for _, prefix := range validUris { |
|
839 |
// TODO: handle unicode here |
|
840 |
// case-insensitive prefix test |
|
841 |
if len(link) > len(prefix) && bytes.Equal(bytes.ToLower(link[:len(prefix)]), prefix) && isalnum(link[len(prefix)]) { |
|
842 |
return true |
|
843 |
} |
|
844 |
} |
|
845 |
|
|
846 |
return false |
|
847 |
} |
|
848 |
|
|
849 |
// return the length of the given tag, or 0 is it's not valid |
|
850 |
func tagLength(data []byte, autolink *int) int { |
|
851 |
var i, j int |
|
852 |
|
|
853 |
// a valid tag can't be shorter than 3 chars |
|
854 |
if len(data) < 3 { |
|
855 |
return 0 |
|
856 |
} |
|
857 |
|
|
858 |
// begins with a '<' optionally followed by '/', followed by letter or number |
|
859 |
if data[0] != '<' { |
|
860 |
return 0 |
|
861 |
} |
|
862 |
if data[1] == '/' { |
|
863 |
i = 2 |
|
864 |
} else { |
|
865 |
i = 1 |
|
866 |
} |
|
867 |
|
|
868 |
if !isalnum(data[i]) { |
|
869 |
return 0 |
|
870 |
} |
|
871 |
|
|
872 |
// scheme test |
|
873 |
*autolink = LINK_TYPE_NOT_AUTOLINK |
|
874 |
|
|
875 |
// try to find the beginning of an URI |
|
876 |
for i < len(data) && (isalnum(data[i]) || data[i] == '.' || data[i] == '+' || data[i] == '-') { |
|
877 |
i++ |
|
878 |
} |
|
879 |
|
|
880 |
if i > 1 && i < len(data) && data[i] == '@' { |
|
881 |
if j = isMailtoAutoLink(data[i:]); j != 0 { |
|
882 |
*autolink = LINK_TYPE_EMAIL |
|
883 |
return i + j |
|
884 |
} |
|
885 |
} |
|
886 |
|
|
887 |
if i > 2 && i < len(data) && data[i] == ':' { |
|
888 |
*autolink = LINK_TYPE_NORMAL |
|
889 |
i++ |
|
890 |
} |
|
891 |
|
|
892 |
// complete autolink test: no whitespace or ' or " |
|
893 |
switch { |
|
894 |
case i >= len(data): |
|
895 |
*autolink = LINK_TYPE_NOT_AUTOLINK |
|
896 |
case *autolink != 0: |
|
897 |
j = i |
|
898 |
|
|
899 |
for i < len(data) { |
|
900 |
if data[i] == '\\' { |
|
901 |
i += 2 |
|
902 |
} else if data[i] == '>' || data[i] == '\'' || data[i] == '"' || isspace(data[i]) { |
|
903 |
break |
|
904 |
} else { |
|
905 |
i++ |
|
906 |
} |
|
907 |
|
|
908 |
} |
|
909 |
|
|
910 |
if i >= len(data) { |
|
911 |
return 0 |
|
912 |
} |
|
913 |
if i > j && data[i] == '>' { |
|
914 |
return i + 1 |
|
915 |
} |
|
916 |
|
|
917 |
// one of the forbidden chars has been found |
|
918 |
*autolink = LINK_TYPE_NOT_AUTOLINK |
|
919 |
} |
|
920 |
|
|
921 |
// look for something looking like a tag end |
|
922 |
for i < len(data) && data[i] != '>' { |
|
923 |
i++ |
|
924 |
} |
|
925 |
if i >= len(data) { |
|
926 |
return 0 |
|
927 |
} |
|
928 |
return i + 1 |
|
929 |
} |
|
930 |
|
|
931 |
// look for the address part of a mail autolink and '>' |
|
932 |
// this is less strict than the original markdown e-mail address matching |
|
933 |
func isMailtoAutoLink(data []byte) int { |
|
934 |
nb := 0 |
|
935 |
|
|
936 |
// address is assumed to be: [-@._a-zA-Z0-9]+ with exactly one '@' |
|
937 |
for i := 0; i < len(data); i++ { |
|
938 |
if isalnum(data[i]) { |
|
939 |
continue |
|
940 |
} |
|
941 |
|
|
942 |
switch data[i] { |
|
943 |
case '@': |
|
944 |
nb++ |
|
945 |
|
|
946 |
case '-', '.', '_': |
|
947 |
// Do nothing. |
|
948 |
|
|
949 |
case '>': |
|
950 |
if nb == 1 { |
|
951 |
return i + 1 |
|
952 |
} else { |
|
953 |
return 0 |
|
954 |
} |
|
955 |
default: |
|
956 |
return 0 |
|
957 |
} |
|
958 |
} |
|
959 |
|
|
960 |
return 0 |
|
961 |
} |
|
962 |
|
|
963 |
// look for the next emph char, skipping other constructs |
|
964 |
func helperFindEmphChar(data []byte, c byte) int { |
|
965 |
i := 0 |
|
966 |
|
|
967 |
for i < len(data) { |
|
968 |
for i < len(data) && data[i] != c && data[i] != '`' && data[i] != '[' { |
|
969 |
i++ |
|
970 |
} |
|
971 |
if i >= len(data) { |
|
972 |
return 0 |
|
973 |
} |
|
974 |
// do not count escaped chars |
|
975 |
if i != 0 && data[i-1] == '\\' { |
|
976 |
i++ |
|
977 |
continue |
|
978 |
} |
|
979 |
if data[i] == c { |
|
980 |
return i |
|
981 |
} |
|
982 |
|
|
983 |
if data[i] == '`' { |
|
984 |
// skip a code span |
|
985 |
tmpI := 0 |
|
986 |
i++ |
|
987 |
for i < len(data) && data[i] != '`' { |
|
988 |
if tmpI == 0 && data[i] == c { |
|
989 |
tmpI = i |
|
990 |
} |
|
991 |
i++ |
|
992 |
} |
|
993 |
if i >= len(data) { |
|
994 |
return tmpI |
|
995 |
} |
|
996 |
i++ |
|
997 |
} else if data[i] == '[' { |
|
998 |
// skip a link |
|
999 |
tmpI := 0 |
|
1000 |
i++ |
|
1001 |
for i < len(data) && data[i] != ']' { |
|
1002 |
if tmpI == 0 && data[i] == c { |
|
1003 |
tmpI = i |
|
1004 |
} |
|
1005 |
i++ |
|
1006 |
} |
|
1007 |
i++ |
|
1008 |
for i < len(data) && (data[i] == ' ' || data[i] == '\n') { |
|
1009 |
i++ |
|
1010 |
} |
|
1011 |
if i >= len(data) { |
|
1012 |
return tmpI |
|
1013 |
} |
|
1014 |
if data[i] != '[' && data[i] != '(' { // not a link |
|
1015 |
if tmpI > 0 { |
|
1016 |
return tmpI |
|
1017 |
} else { |
|
1018 |
continue |
|
1019 |
} |
|
1020 |
} |
|
1021 |
cc := data[i] |
|
1022 |
i++ |
|
1023 |
for i < len(data) && data[i] != cc { |
|
1024 |
if tmpI == 0 && data[i] == c { |
|
1025 |
return i |
|
1026 |
} |
|
1027 |
i++ |
|
1028 |
} |
|
1029 |
if i >= len(data) { |
|
1030 |
return tmpI |
|
1031 |
} |
|
1032 |
i++ |
|
1033 |
} |
|
1034 |
} |
|
1035 |
return 0 |
|
1036 |
} |
|
1037 |
|
|
1038 |
func helperEmphasis(p *parser, out *bytes.Buffer, data []byte, c byte) int { |
|
1039 |
i := 0 |
|
1040 |
|
|
1041 |
// skip one symbol if coming from emph3 |
|
1042 |
if len(data) > 1 && data[0] == c && data[1] == c { |
|
1043 |
i = 1 |
|
1044 |
} |
|
1045 |
|
|
1046 |
for i < len(data) { |
|
1047 |
length := helperFindEmphChar(data[i:], c) |
|
1048 |
if length == 0 { |
|
1049 |
return 0 |
|
1050 |
} |
|
1051 |
i += length |
|
1052 |
if i >= len(data) { |
|
1053 |
return 0 |
|
1054 |
} |
|
1055 |
|
|
1056 |
if i+1 < len(data) && data[i+1] == c { |
|
1057 |
i++ |
|
1058 |
continue |
|
1059 |
} |
|
1060 |
|
|
1061 |
if data[i] == c && !isspace(data[i-1]) { |
|
1062 |
|
|
1063 |
if p.flags&EXTENSION_NO_INTRA_EMPHASIS != 0 { |
|
1064 |
if !(i+1 == len(data) || isspace(data[i+1]) || ispunct(data[i+1])) { |
|
1065 |
continue |
|
1066 |
} |
|
1067 |
} |
|
1068 |
|
|
1069 |
var work bytes.Buffer |
|
1070 |
p.inline(&work, data[:i]) |
|
1071 |
p.r.Emphasis(out, work.Bytes()) |
|
1072 |
return i + 1 |
|
1073 |
} |
|
1074 |
} |
|
1075 |
|
|
1076 |
return 0 |
|
1077 |
} |
|
1078 |
|
|
1079 |
func helperDoubleEmphasis(p *parser, out *bytes.Buffer, data []byte, c byte) int { |
|
1080 |
i := 0 |
|
1081 |
|
|
1082 |
for i < len(data) { |
|
1083 |
length := helperFindEmphChar(data[i:], c) |
|
1084 |
if length == 0 { |
|
1085 |
return 0 |
|
1086 |
} |
|
1087 |
i += length |
|
1088 |
|
|
1089 |
if i+1 < len(data) && data[i] == c && data[i+1] == c && i > 0 && !isspace(data[i-1]) { |
|
1090 |
var work bytes.Buffer |
|
1091 |
p.inline(&work, data[:i]) |
|
1092 |
|
|
1093 |
if work.Len() > 0 { |
|
1094 |
// pick the right renderer |
|
1095 |
if c == '~' { |
|
1096 |
p.r.StrikeThrough(out, work.Bytes()) |
|
1097 |
} else { |
|
1098 |
p.r.DoubleEmphasis(out, work.Bytes()) |
|
1099 |
} |
|
1100 |
} |
|
1101 |
return i + 2 |
|
1102 |
} |
|
1103 |
i++ |
|
1104 |
} |
|
1105 |
return 0 |
|
1106 |
} |
|
1107 |
|
|
1108 |
func helperTripleEmphasis(p *parser, out *bytes.Buffer, data []byte, offset int, c byte) int { |
|
1109 |
i := 0 |
|
1110 |
origData := data |
|
1111 |
data = data[offset:] |
|
1112 |
|
|
1113 |
for i < len(data) { |
|
1114 |
length := helperFindEmphChar(data[i:], c) |
|
1115 |
if length == 0 { |
|
1116 |
return 0 |
|
1117 |
} |
|
1118 |
i += length |
|
1119 |
|
|
1120 |
// skip whitespace preceded symbols |
|
1121 |
if data[i] != c || isspace(data[i-1]) { |
|
1122 |
continue |
|
1123 |
} |
|
1124 |
|
|
1125 |
switch { |
|
1126 |
case i+2 < len(data) && data[i+1] == c && data[i+2] == c: |
|
1127 |
// triple symbol found |
|
1128 |
var work bytes.Buffer |
|
1129 |
|
|
1130 |
p.inline(&work, data[:i]) |
|
1131 |
if work.Len() > 0 { |
|
1132 |
p.r.TripleEmphasis(out, work.Bytes()) |
|
1133 |
} |
|
1134 |
return i + 3 |
|
1135 |
case (i+1 < len(data) && data[i+1] == c): |
|
1136 |
// double symbol found, hand over to emph1 |
|
1137 |
length = helperEmphasis(p, out, origData[offset-2:], c) |
|
1138 |
if length == 0 { |
|
1139 |
return 0 |
|
1140 |
} else { |
|
1141 |
return length - 2 |
|
1142 |
} |
|
1143 |
default: |
|
1144 |
// single symbol found, hand over to emph2 |
|
1145 |
length = helperDoubleEmphasis(p, out, origData[offset-1:], c) |
|
1146 |
if length == 0 { |
|
1147 |
return 0 |
|
1148 |
} else { |
|
1149 |
return length - 1 |
|
1150 |
} |
|
1151 |
} |
|
1152 |
} |
|
1153 |
return 0 |
|
1154 |
} |