Annotation of mandoc/mandoc_html.3, Revision 1.5
1.5 ! schwarze 1: .\" $Id: mandoc_html.3,v 1.4 2017/01/25 02:14:43 schwarze Exp $
1.1 schwarze 2: .\"
1.3 schwarze 3: .\" Copyright (c) 2014, 2017 Ingo Schwarze <schwarze@openbsd.org>
1.1 schwarze 4: .\"
5: .\" Permission to use, copy, modify, and distribute this software for any
6: .\" purpose with or without fee is hereby granted, provided that the above
7: .\" copyright notice and this permission notice appear in all copies.
8: .\"
9: .\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10: .\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11: .\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12: .\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13: .\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14: .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15: .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16: .\"
1.5 ! schwarze 17: .Dd $Mdocdate: January 25 2017 $
1.1 schwarze 18: .Dt MANDOC_HTML 3
19: .Os
20: .Sh NAME
21: .Nm mandoc_html
22: .Nd internals of the mandoc HTML formatter
23: .Sh SYNOPSIS
24: .In "html.h"
25: .Ft void
26: .Fn print_gen_decls "struct html *h"
27: .Ft void
28: .Fn print_gen_head "struct html *h"
29: .Ft struct tag *
30: .Fo print_otag
31: .Fa "struct html *h"
32: .Fa "enum htmltag tag"
1.2 schwarze 33: .Fa "const char *fmt"
34: .Fa ...
1.1 schwarze 35: .Fc
36: .Ft void
37: .Fo print_tagq
38: .Fa "struct html *h"
39: .Fa "const struct tag *until"
40: .Fc
41: .Ft void
42: .Fo print_stagq
43: .Fa "struct html *h"
44: .Fa "const struct tag *suntil"
45: .Fc
46: .Ft void
47: .Fo print_text
48: .Fa "struct html *h"
49: .Fa "const char *word"
50: .Fc
51: .Sh DESCRIPTION
52: The mandoc HTML formatter is not a formal library.
53: However, as it is compiled into more than one program, in particular
54: .Xr mandoc 1
55: and
56: .Xr man.cgi 8 ,
57: and because it may be security-critical in some contexts,
58: some documentation is useful to help to use it correctly and
59: to prevent XSS vulnerabilities.
60: .Pp
61: The formatter produces HTML output on the standard output.
62: Since proper escaping is usually required and best taken care of
63: at one central place, the language-specific formatters
64: .Po
65: .Pa *_html.c ,
66: see
67: .Sx FILES
68: .Pc
69: are not supposed to print directly to
70: .Dv stdout
71: using functions like
72: .Xr printf 3 ,
73: .Xr putc 3 ,
74: .Xr puts 3 ,
75: or
76: .Xr write 2 .
77: Instead, they are expected to use the output functions declared in
78: .Pa html.h
79: and implemented as part of the main HTML formatting engine in
80: .Pa html.c .
81: .Ss Data structures
82: These structures are declared in
83: .Pa html.h .
84: .Bl -tag -width Ds
85: .It Vt struct html
86: Internal state of the HTML formatter.
87: .It Vt struct tag
88: One entry for the LIFO stack of HTML elements.
89: Members are
90: .Fa "enum htmltag tag"
91: and
92: .Fa "struct tag *next" .
93: .El
94: .Ss Private interface functions
95: The function
96: .Fn print_gen_decls
97: prints the opening
98: .Ao Pf \&? Ic xml ? Ac
99: and
100: .Aq Pf \&! Ic DOCTYPE
101: declarations required for the current document type.
102: .Pp
103: The function
104: .Fn print_gen_head
105: prints the opening
106: .Aq Ic META
107: and
108: .Aq Ic LINK
109: elements for the document
110: .Aq Ic HEAD ,
111: using the
112: .Fa style
113: member of
114: .Fa h
115: unless that is
116: .Dv NULL .
117: It uses
118: .Fn print_otag
119: which takes care of properly encoding attributes,
120: which is relevant for the
121: .Fa style
122: link in particular.
123: .Pp
124: The function
125: .Fn print_otag
126: prints the start tag of an HTML element with the name
127: .Fa tag ,
1.2 schwarze 128: optionally including the attributes specified by
129: .Fa fmt .
130: If
131: .Fa fmt
132: is the empty string, no attributes are written.
133: Each letter of
134: .Fa fmt
135: specifies one attribute to write.
136: Most attributes require one
137: .Va char *
138: argument which becomes the value of the attribute.
139: The arguments have to be given in the same order as the attribute letters.
1.5 ! schwarze 140: If an argument is
! 141: .Dv NULL ,
! 142: the respective attribute is not written.
1.2 schwarze 143: .Bl -tag -width 1n -offset indent
144: .It Cm c
145: Print a
146: .Cm class
147: attribute.
148: .It Cm h
149: Print a
150: .Cm href
151: attribute.
1.3 schwarze 152: This attribute letter can optionally be followed by a modifier letter.
153: If followed by
154: .Cm R ,
155: it formats the link as a local one by prefixing a
156: .Sq #
157: character.
158: If followed by
159: .Cm I ,
160: it interpretes the argument as a header file name
161: and generates a link using the
162: .Xr mandoc 1
163: .Fl O Cm includes
164: option.
165: If followed by
166: .Cm M ,
167: it takes two arguments instead of one, a manual page name and
168: section, and formats them as a link to a manual page using the
169: .Xr mandoc 1
170: .Fl O Cm man
171: option.
1.2 schwarze 172: .It Cm i
173: Print an
174: .Cm id
175: attribute.
176: .It Cm \&?
177: Print an arbitrary attribute.
178: This format letter requires two
179: .Vt char *
180: arguments, the attribute name and the value.
1.5 ! schwarze 181: The name must not be
! 182: .Dv NULL .
1.2 schwarze 183: .It Cm s
184: Print a
185: .Cm style
186: attribute.
187: If present, it must be the last format letter.
188: In contrast to the other format letters, this one does not yet
1.5 ! schwarze 189: print the value and does not take an argument.
1.2 schwarze 190: Instead, the rest of the format string consists of pairs of
191: argument type letters and style name letters.
192: .El
193: .Pp
194: Argument type letters each require on argument as follows:
195: .Bl -tag -width 1n -offset indent
196: .It Cm h
197: Requires one
198: .Vt int
199: argument, interpreted as a horizontal length in units of
200: .Dv SCALE_EN .
201: .It Cm s
202: Requires one
203: .Vt char *
204: argument, used as a style value.
205: .It Cm u
206: Requires one
207: .Vt struct roffsu *
208: argument, used as a length.
209: .It Cm v
210: Requires one
211: .Vt int
212: argument, interpreted as a vertical length in units of
213: .Dv SCALE_VS .
214: .It Cm w
215: Requires one
216: .Vt char *
217: argument, interpreted as an
218: .Xr mdoc 7 Ns -style
219: width specifier.
1.5 ! schwarze 220: If the argument is
! 221: .Dv NULL ,
! 222: nothing is printed for this pair.
1.4 schwarze 223: .It Cm W
224: Similar to
225: .Cm w ,
226: but makes the width negative by multiplying it with \(mi1.
1.2 schwarze 227: .El
228: .Pp
229: Style name letters decide what to do with the preceding argument:
230: .Bl -tag -width 1n -offset indent
231: .It Cm b
232: Set
233: .Cm margin-bottom
234: to the given length.
235: .It Cm h
236: Set
237: .Cm height
238: to the given length.
239: .It Cm i
240: Set
241: .Cm text-indent
242: to the given length.
243: .It Cm l
244: Set
245: .Cm margin-left
246: to the given length.
247: .It Cm t
248: Set
249: .Cm margin-top
250: to the given length.
251: .It Cm w
252: Set
253: .Cm width
254: to the given length.
255: .It Cm W
256: Set
257: .Cm min-width
258: to the given length.
259: .It Cm \&?
260: The special pair
261: .Cm s?
262: requires two
263: .Vt char *
264: arguments.
265: The first is the style name, the second its value.
1.5 ! schwarze 266: The style name must not be
! 267: .Dv NULL .
1.2 schwarze 268: .El
269: .Pp
270: .Fn print_otag
271: uses the private function
1.1 schwarze 272: .Fn print_encode
273: to take care of HTML encoding.
274: If required by the element type, it remembers in
275: .Fa h
276: that the element is open.
277: The function
278: .Fn print_tagq
279: is used to close out all open elements up to and including
280: .Fa until ;
281: .Fn print_stagq
282: is a variant to close out all open elements up to but excluding
283: .Fa suntil .
284: .Pp
285: The function
286: .Fn print_text
287: prints HTML element content.
288: It uses the private function
289: .Fn print_encode
290: to take care of HTML encoding.
291: If the document has requested a non-standard font, for example using a
292: .Xr roff 7
293: .Ic \ef
294: font escape sequence,
295: .Fn print_text
296: wraps
297: .Fa word
298: in an HTML font selection element using the
299: .Fn print_otag
300: and
301: .Fn print_tagq
302: functions.
303: .Pp
304: The functions
305: .Fn html_strlen ,
306: .Fn print_eqn ,
307: .Fn print_tbl ,
308: and
309: .Fn print_tblclose
310: are not yet documented.
311: .Sh FILES
312: .Bl -tag -width mandoc_aux.c -compact
313: .It Pa main.h
314: declarations of public functions for use by the main program,
315: not yet documented
316: .It Pa html.h
317: declarations of data types and private functions
318: for use by language-specific HTML formatters
319: .It Pa html.c
320: main HTML formatting engine and utility functions
321: .It Pa mdoc_html.c
322: .Xr mdoc 7
323: HTML formatter
324: .It Pa man_html.c
325: .Xr man 7
326: HTML formatter
327: .It Pa tbl_html.c
328: .Xr tbl 7
329: HTML formatter
330: .It Pa eqn_html.c
331: .Xr eqn 7
332: HTML formatter
333: .It Pa out.h
334: declarations of data types and private functions
335: for shared use by all mandoc formatters,
336: not yet documented
337: .It Pa out.c
338: private functions for shared use by all mandoc formatters
339: .It Pa mandoc_aux.h
340: declarations of common mandoc utility functions, see
341: .Xr mandoc 3
342: .It Pa mandoc_aux.c
343: implementation of common mandoc utility functions
344: .El
345: .Sh SEE ALSO
346: .Xr mandoc 1 ,
347: .Xr mandoc 3 ,
348: .Xr man.cgi 8
349: .Sh AUTHORS
350: .An -nosplit
351: The mandoc HTML formatter was written by
352: .An Kristaps Dzonsons Aq Mt kristaps@bsd.lv .
1.5 ! schwarze 353: It is maintained by
! 354: .An Ingo Schwarze Aq Mt schwarze@openbsd.org ,
! 355: who also wrote this manual.
CVSweb