roff.go 6.4 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286
  1. package md2man
  2. import (
  3. "bytes"
  4. "fmt"
  5. "html"
  6. "strings"
  7. "github.com/russross/blackfriday"
  8. )
  9. type roffRenderer struct {
  10. ListCounters []int
  11. }
  12. // RoffRenderer creates a new blackfriday Renderer for generating roff documents
  13. // from markdown
  14. func RoffRenderer(flags int) blackfriday.Renderer {
  15. return &roffRenderer{}
  16. }
  17. func (r *roffRenderer) GetFlags() int {
  18. return 0
  19. }
  20. func (r *roffRenderer) TitleBlock(out *bytes.Buffer, text []byte) {
  21. out.WriteString(".TH ")
  22. splitText := bytes.Split(text, []byte("\n"))
  23. for i, line := range splitText {
  24. line = bytes.TrimPrefix(line, []byte("% "))
  25. if i == 0 {
  26. line = bytes.Replace(line, []byte("("), []byte("\" \""), 1)
  27. line = bytes.Replace(line, []byte(")"), []byte("\" \""), 1)
  28. }
  29. line = append([]byte("\""), line...)
  30. line = append(line, []byte("\" ")...)
  31. out.Write(line)
  32. }
  33. out.WriteString("\n")
  34. // disable hyphenation
  35. out.WriteString(".nh\n")
  36. // disable justification (adjust text to left margin only)
  37. out.WriteString(".ad l\n")
  38. }
  39. func (r *roffRenderer) BlockCode(out *bytes.Buffer, text []byte, lang string) {
  40. out.WriteString("\n.PP\n.RS\n\n.nf\n")
  41. escapeSpecialChars(out, text)
  42. out.WriteString("\n.fi\n.RE\n")
  43. }
  44. func (r *roffRenderer) BlockQuote(out *bytes.Buffer, text []byte) {
  45. out.WriteString("\n.PP\n.RS\n")
  46. out.Write(text)
  47. out.WriteString("\n.RE\n")
  48. }
  49. func (r *roffRenderer) BlockHtml(out *bytes.Buffer, text []byte) { // nolint: golint
  50. out.Write(text)
  51. }
  52. func (r *roffRenderer) Header(out *bytes.Buffer, text func() bool, level int, id string) {
  53. marker := out.Len()
  54. switch {
  55. case marker == 0:
  56. // This is the doc header
  57. out.WriteString(".TH ")
  58. case level == 1:
  59. out.WriteString("\n\n.SH ")
  60. case level == 2:
  61. out.WriteString("\n.SH ")
  62. default:
  63. out.WriteString("\n.SS ")
  64. }
  65. if !text() {
  66. out.Truncate(marker)
  67. return
  68. }
  69. }
  70. func (r *roffRenderer) HRule(out *bytes.Buffer) {
  71. out.WriteString("\n.ti 0\n\\l'\\n(.lu'\n")
  72. }
  73. func (r *roffRenderer) List(out *bytes.Buffer, text func() bool, flags int) {
  74. marker := out.Len()
  75. r.ListCounters = append(r.ListCounters, 1)
  76. out.WriteString("\n.RS\n")
  77. if !text() {
  78. out.Truncate(marker)
  79. return
  80. }
  81. r.ListCounters = r.ListCounters[:len(r.ListCounters)-1]
  82. out.WriteString("\n.RE\n")
  83. }
  84. func (r *roffRenderer) ListItem(out *bytes.Buffer, text []byte, flags int) {
  85. if flags&blackfriday.LIST_TYPE_ORDERED != 0 {
  86. out.WriteString(fmt.Sprintf(".IP \"%3d.\" 5\n", r.ListCounters[len(r.ListCounters)-1]))
  87. r.ListCounters[len(r.ListCounters)-1]++
  88. } else {
  89. out.WriteString(".IP \\(bu 2\n")
  90. }
  91. out.Write(text)
  92. out.WriteString("\n")
  93. }
  94. func (r *roffRenderer) Paragraph(out *bytes.Buffer, text func() bool) {
  95. marker := out.Len()
  96. out.WriteString("\n.PP\n")
  97. if !text() {
  98. out.Truncate(marker)
  99. return
  100. }
  101. if marker != 0 {
  102. out.WriteString("\n")
  103. }
  104. }
  105. func (r *roffRenderer) Table(out *bytes.Buffer, header []byte, body []byte, columnData []int) {
  106. out.WriteString("\n.TS\nallbox;\n")
  107. maxDelims := 0
  108. lines := strings.Split(strings.TrimRight(string(header), "\n")+"\n"+strings.TrimRight(string(body), "\n"), "\n")
  109. for _, w := range lines {
  110. curDelims := strings.Count(w, "\t")
  111. if curDelims > maxDelims {
  112. maxDelims = curDelims
  113. }
  114. }
  115. out.Write([]byte(strings.Repeat("l ", maxDelims+1) + "\n"))
  116. out.Write([]byte(strings.Repeat("l ", maxDelims+1) + ".\n"))
  117. out.Write(header)
  118. if len(header) > 0 {
  119. out.Write([]byte("\n"))
  120. }
  121. out.Write(body)
  122. out.WriteString("\n.TE\n")
  123. }
  124. func (r *roffRenderer) TableRow(out *bytes.Buffer, text []byte) {
  125. if out.Len() > 0 {
  126. out.WriteString("\n")
  127. }
  128. out.Write(text)
  129. }
  130. func (r *roffRenderer) TableHeaderCell(out *bytes.Buffer, text []byte, align int) {
  131. if out.Len() > 0 {
  132. out.WriteString("\t")
  133. }
  134. if len(text) == 0 {
  135. text = []byte{' '}
  136. }
  137. out.Write([]byte("\\fB\\fC" + string(text) + "\\fR"))
  138. }
  139. func (r *roffRenderer) TableCell(out *bytes.Buffer, text []byte, align int) {
  140. if out.Len() > 0 {
  141. out.WriteString("\t")
  142. }
  143. if len(text) > 30 {
  144. text = append([]byte("T{\n"), text...)
  145. text = append(text, []byte("\nT}")...)
  146. }
  147. if len(text) == 0 {
  148. text = []byte{' '}
  149. }
  150. out.Write(text)
  151. }
  152. func (r *roffRenderer) Footnotes(out *bytes.Buffer, text func() bool) {
  153. }
  154. func (r *roffRenderer) FootnoteItem(out *bytes.Buffer, name, text []byte, flags int) {
  155. }
  156. func (r *roffRenderer) AutoLink(out *bytes.Buffer, link []byte, kind int) {
  157. out.WriteString("\n\\[la]")
  158. out.Write(link)
  159. out.WriteString("\\[ra]")
  160. }
  161. func (r *roffRenderer) CodeSpan(out *bytes.Buffer, text []byte) {
  162. out.WriteString("\\fB\\fC")
  163. escapeSpecialChars(out, text)
  164. out.WriteString("\\fR")
  165. }
  166. func (r *roffRenderer) DoubleEmphasis(out *bytes.Buffer, text []byte) {
  167. out.WriteString("\\fB")
  168. out.Write(text)
  169. out.WriteString("\\fP")
  170. }
  171. func (r *roffRenderer) Emphasis(out *bytes.Buffer, text []byte) {
  172. out.WriteString("\\fI")
  173. out.Write(text)
  174. out.WriteString("\\fP")
  175. }
  176. func (r *roffRenderer) Image(out *bytes.Buffer, link []byte, title []byte, alt []byte) {
  177. }
  178. func (r *roffRenderer) LineBreak(out *bytes.Buffer) {
  179. out.WriteString("\n.br\n")
  180. }
  181. func (r *roffRenderer) Link(out *bytes.Buffer, link []byte, title []byte, content []byte) {
  182. out.Write(content)
  183. r.AutoLink(out, link, 0)
  184. }
  185. func (r *roffRenderer) RawHtmlTag(out *bytes.Buffer, tag []byte) { // nolint: golint
  186. out.Write(tag)
  187. }
  188. func (r *roffRenderer) TripleEmphasis(out *bytes.Buffer, text []byte) {
  189. out.WriteString("\\s+2")
  190. out.Write(text)
  191. out.WriteString("\\s-2")
  192. }
  193. func (r *roffRenderer) StrikeThrough(out *bytes.Buffer, text []byte) {
  194. }
  195. func (r *roffRenderer) FootnoteRef(out *bytes.Buffer, ref []byte, id int) {
  196. }
  197. func (r *roffRenderer) Entity(out *bytes.Buffer, entity []byte) {
  198. out.WriteString(html.UnescapeString(string(entity)))
  199. }
  200. func (r *roffRenderer) NormalText(out *bytes.Buffer, text []byte) {
  201. escapeSpecialChars(out, text)
  202. }
  203. func (r *roffRenderer) DocumentHeader(out *bytes.Buffer) {
  204. }
  205. func (r *roffRenderer) DocumentFooter(out *bytes.Buffer) {
  206. }
  207. func needsBackslash(c byte) bool {
  208. for _, r := range []byte("-_&\\~") {
  209. if c == r {
  210. return true
  211. }
  212. }
  213. return false
  214. }
  215. func escapeSpecialChars(out *bytes.Buffer, text []byte) {
  216. for i := 0; i < len(text); i++ {
  217. // escape initial apostrophe or period
  218. if len(text) >= 1 && (text[0] == '\'' || text[0] == '.') {
  219. out.WriteString("\\&")
  220. }
  221. // directly copy normal characters
  222. org := i
  223. for i < len(text) && !needsBackslash(text[i]) {
  224. i++
  225. }
  226. if i > org {
  227. out.Write(text[org:i])
  228. }
  229. // escape a character
  230. if i >= len(text) {
  231. break
  232. }
  233. out.WriteByte('\\')
  234. out.WriteByte(text[i])
  235. }
  236. }