Welcome to little lamb

Code » md4c » lila » tree

[lila] / src / md4c.h

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
/*
 * MD4C: Markdown parser for C
 * (http://github.com/mity/md4c)
 *
 * Copyright (c) 2016-2020 Martin Mitas
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 */

#ifndef MD4C_H
#define MD4C_H

#ifdef __cplusplus
    extern "C" {
#endif

#if defined MD4C_USE_UTF16
    /* Magic to support UTF-16. Note that in order to use it, you have to define
     * the macro MD4C_USE_UTF16 both when building MD4C as well as when
     * including this header in your code. */
    #ifdef _WIN32
        #include <windows.h>
        typedef WCHAR       MD_CHAR;
    #else
        #error MD4C_USE_UTF16 is only supported on Windows.
    #endif
#else
    typedef char            MD_CHAR;
#endif

typedef unsigned MD_SIZE;
typedef unsigned MD_OFFSET;


/* Block represents a part of document hierarchy structure like a paragraph
 * or list item.
 */
typedef enum MD_BLOCKTYPE {
    /* <body>...</body> */
    MD_BLOCK_DOC = 0,

    /* <blockquote>...</blockquote> */
    MD_BLOCK_QUOTE,

    /* <div class="box">...</div> */
    MD_BLOCK_BOX,

    /* indented block */
    MD_BLOCK_INDENT,

    /* <ul>...</ul>
     * Detail: Structure MD_BLOCK_UL_DETAIL. */
    MD_BLOCK_UL,

    /* <ol>...</ol>
     * Detail: Structure MD_BLOCK_OL_DETAIL. */
    MD_BLOCK_OL,

    /* <li>...</li>
     * Detail: Structure MD_BLOCK_LI_DETAIL. */
    MD_BLOCK_LI,

    /* <hr> */
    MD_BLOCK_HR,

    /* <h1>...</h1> (for levels up to 6)
     * Detail: Structure MD_BLOCK_H_DETAIL. */
    MD_BLOCK_H,

    /* <pre><code>...</code></pre>
     * Note the text lines within code blocks are terminated with '\n'
     * instead of explicit MD_TEXT_BR. */
    MD_BLOCK_CODE,

    /* Raw HTML block. This itself does not correspond to any particular HTML
     * tag. The contents of it _is_ raw HTML source intended to be put
     * in verbatim form to the HTML output. */
    MD_BLOCK_HTML,

    /* <p>...</p> */
    MD_BLOCK_P,

    /* <table>...</table> and its contents.
     * Detail: Structure MD_BLOCK_TABLE_DETAIL (for MD_BLOCK_TABLE),
     *         structure MD_BLOCK_TD_DETAIL (for MD_BLOCK_TH and MD_BLOCK_TD)
     * Note all of these are used only if extension MD_FLAG_TABLES is enabled. */
    MD_BLOCK_TABLE,
    MD_BLOCK_THEAD,
    MD_BLOCK_TBODY,
    MD_BLOCK_TR,
    MD_BLOCK_TH,
    MD_BLOCK_TD
} MD_BLOCKTYPE;

/* Span represents an in-line piece of a document which should be rendered with
 * the same font, color and other attributes. A sequence of spans forms a block
 * like paragraph or list item. */
typedef enum MD_SPANTYPE {
    /* <em>...</em> */
    MD_SPAN_EM,

    /* <strong>...</strong> */
    MD_SPAN_STRONG,

    /* <a href="xxx">...</a>
     * Detail: Structure MD_SPAN_A_DETAIL. */
    MD_SPAN_A,

    /* <img src="xxx">...</a>
     * Detail: Structure MD_SPAN_IMG_DETAIL.
     * Note: Image text can contain nested spans and even nested images.
     * If rendered into ALT attribute of HTML <IMG> tag, it's responsibility
     * of the parser to deal with it.
     */
    MD_SPAN_IMG,

    /* <code>...</code> */
    MD_SPAN_CODE,

    /* <del>...</del>
     * Note: Recognized only when MD_FLAG_STRIKETHROUGH is enabled.
     */
    MD_SPAN_DEL,

    /* <span class="highlight">...</span>
     * Note: Recognized only when MD_FLAG_HIGHLIGHT is enabled.
     */
    MD_SPAN_HIGHLIGHT,

    /* For recognizing inline ($) and display ($$) equations
     * Note: Recognized only when MD_FLAG_LATEXMATHSPANS is enabled.
     */
    MD_SPAN_LATEXMATH,
    MD_SPAN_LATEXMATH_DISPLAY,

    /* Wiki links
     * Note: Recognized only when MD_FLAG_WIKILINKS is enabled.
     */
    MD_SPAN_WIKILINK,

    /* <u>...</u>
     * Note: Recognized only when MD_FLAG_UNDERLINE is enabled. */
    MD_SPAN_U
} MD_SPANTYPE;

/* Text is the actual textual contents of span. */
typedef enum MD_TEXTTYPE {
    /* Normal text. */
    MD_TEXT_NORMAL = 0,

    /* NULL character. CommonMark requires replacing NULL character with
     * the replacement char U+FFFD, so this allows caller to do that easily. */
    MD_TEXT_NULLCHAR,

    /* Line breaks.
     * Note these are not sent from blocks with verbatim output (MD_BLOCK_CODE
     * or MD_BLOCK_HTML). In such cases, '\n' is part of the text itself. */
    MD_TEXT_BR,         /* <br> (hard break) */
    MD_TEXT_SOFTBR,     /* '\n' in source text where it is not semantically meaningful (soft break) */

    /* Entity.
     * (a) Named entity, e.g. &nbsp; 
     *     (Note MD4C does not have a list of known entities.
     *     Anything matching the regexp /&[A-Za-z][A-Za-z0-9]{1,47};/ is
     *     treated as a named entity.)
     * (b) Numerical entity, e.g. &#1234;
     * (c) Hexadecimal entity, e.g. &#x12AB;
     *
     * As MD4C is mostly encoding agnostic, application gets the verbatim
     * entity text into the MD_PARSER::text_callback(). */
    MD_TEXT_ENTITY,

    /* Text in a code block (inside MD_BLOCK_CODE) or inlined code (`code`).
     * If it is inside MD_BLOCK_CODE, it includes spaces for indentation and
     * '\n' for new lines. MD_TEXT_BR and MD_TEXT_SOFTBR are not sent for this
     * kind of text. */
    MD_TEXT_CODE,

    /* Text is a raw HTML. If it is contents of a raw HTML block (i.e. not
     * an inline raw HTML), then MD_TEXT_BR and MD_TEXT_SOFTBR are not used.
     * The text contains verbatim '\n' for the new lines. */
    MD_TEXT_HTML,

    /* Text is inside an equation. This is processed the same way as inlined code
     * spans (`code`). */
    MD_TEXT_LATEXMATH
} MD_TEXTTYPE;


/* Alignment enumeration. */
typedef enum MD_ALIGN {
    MD_ALIGN_DEFAULT = 0,   /* When unspecified. */
    MD_ALIGN_LEFT,
    MD_ALIGN_CENTER,
    MD_ALIGN_RIGHT
} MD_ALIGN;


/* String attribute.
 *
 * This wraps strings which are outside of a normal text flow and which are
 * propagated within various detailed structures, but which still may contain
 * string portions of different types like e.g. entities.
 *
 * So, for example, lets consider this image:
 *
 *     ![image alt text](http://example.org/image.png 'foo &quot; bar')
 *
 * The image alt text is propagated as a normal text via the MD_PARSER::text()
 * callback. However, the image title ('foo &quot; bar') is propagated as
 * MD_ATTRIBUTE in MD_SPAN_IMG_DETAIL::title.
 *
 * Then the attribute MD_SPAN_IMG_DETAIL::title shall provide the following:
 *  -- [0]: "foo "   (substr_types[0] == MD_TEXT_NORMAL; substr_offsets[0] == 0)
 *  -- [1]: "&quot;" (substr_types[1] == MD_TEXT_ENTITY; substr_offsets[1] == 4)
 *  -- [2]: " bar"   (substr_types[2] == MD_TEXT_NORMAL; substr_offsets[2] == 10)
 *  -- [3]: (n/a)    (n/a                              ; substr_offsets[3] == 14)
 *
 * Note that these invariants are always guaranteed:
 *  -- substr_offsets[0] == 0
 *  -- substr_offsets[LAST+1] == size
 *  -- Currently, only MD_TEXT_NORMAL, MD_TEXT_ENTITY, MD_TEXT_NULLCHAR
 *     substrings can appear. This could change only of the specification
 *     changes.
 */
typedef struct MD_ATTRIBUTE {
    const MD_CHAR* text;
    MD_SIZE size;
    const MD_TEXTTYPE* substr_types;
    const MD_OFFSET* substr_offsets;
} MD_ATTRIBUTE;


/* Detailed info for MD_BLOCK_UL. */
typedef struct MD_BLOCK_UL_DETAIL {
    int is_tight;           /* Non-zero if tight list, zero if loose. */
    MD_CHAR mark;           /* Item bullet character in MarkDown source of the list, e.g. '-', '+', '*'. */
} MD_BLOCK_UL_DETAIL;

/* Detailed info for MD_BLOCK_OL. */
typedef struct MD_BLOCK_OL_DETAIL {
    unsigned start;         /* Start index of the ordered list. */
    int is_tight;           /* Non-zero if tight list, zero if loose. */
    MD_CHAR mark_delimiter; /* Character delimiting the item marks in MarkDown source, e.g. '.' or ')' */
} MD_BLOCK_OL_DETAIL;

/* Detailed info for MD_BLOCK_LI. */
typedef struct MD_BLOCK_LI_DETAIL {
    int is_task;            /* Can be non-zero only with MD_FLAG_TASKLISTS */
    MD_CHAR task_mark;      /* If is_task, then one of 'x', 'X' or ' '. Undefined otherwise. */
    MD_OFFSET task_mark_offset;  /* If is_task, then offset in the input of the char between '[' and ']'. */
} MD_BLOCK_LI_DETAIL;

/* Detailed info for MD_BLOCK_H. */
typedef struct MD_BLOCK_H_DETAIL {
    unsigned level;         /* Header level (1 - 6) */
} MD_BLOCK_H_DETAIL;

/* Detailed info for MD_BLOCK_CODE. */
typedef struct MD_BLOCK_CODE_DETAIL {
    MD_ATTRIBUTE info;
    MD_ATTRIBUTE lang;
    MD_CHAR fence_char;     /* The character used for fenced code block; or zero for indented code block. */
} MD_BLOCK_CODE_DETAIL;

/* Detailed info for MD_BLOCK_TABLE. */
typedef struct MD_BLOCK_TABLE_DETAIL {
    unsigned col_count;         /* Count of columns in the table. */
    unsigned head_row_count;    /* Count of rows in the table header (currently always 1) */
    unsigned body_row_count;    /* Count of rows in the table body */
} MD_BLOCK_TABLE_DETAIL;

/* Detailed info for MD_BLOCK_TH and MD_BLOCK_TD. */
typedef struct MD_BLOCK_TD_DETAIL {
    MD_ALIGN align;
} MD_BLOCK_TD_DETAIL;

/* Detailed info for MD_BLOCK_BOX. */
typedef struct MB_BLOCK_BOX_DETAIL {
    MD_ATTRIBUTE type;
    MD_ATTRIBUTE title;
} MD_BLOCK_BOX_DETAIL;

/* Detailed info for MD_SPAN_A. */
typedef struct MD_SPAN_A_DETAIL {
    MD_ATTRIBUTE href;
    MD_ATTRIBUTE title;
} MD_SPAN_A_DETAIL;

/* Detailed info for MD_SPAN_IMG. */
typedef struct MD_SPAN_IMG_DETAIL {
    MD_ATTRIBUTE src;
    MD_ATTRIBUTE title;
} MD_SPAN_IMG_DETAIL;

/* Detailed info for MD_SPAN_WIKILINK. */
typedef struct MD_SPAN_WIKILINK {
    MD_ATTRIBUTE target;
} MD_SPAN_WIKILINK_DETAIL;

/* Flags specifying extensions/deviations from CommonMark specification.
 *
 * By default (when MD_PARSER::flags == 0), we follow CommonMark specification.
 * The following flags may allow some extensions or deviations from it.
 */
#define MD_FLAG_COLLAPSEWHITESPACE          0x0001  /* In MD_TEXT_NORMAL, collapse non-trivial whitespace into single ' ' */
#define MD_FLAG_PERMISSIVEATXHEADERS        0x0002  /* Do not require space in ATX headers ( ###header ) */
#define MD_FLAG_PERMISSIVEURLAUTOLINKS      0x0004  /* Recognize URLs as autolinks even without '<', '>' */
#define MD_FLAG_PERMISSIVEEMAILAUTOLINKS    0x0008  /* Recognize e-mails as autolinks even without '<', '>' and 'mailto:' */
#define MD_FLAG_NOINDENTEDCODEBLOCKS        0x0010  /* Disable indented code blocks. (Only fenced code works.) */
#define MD_FLAG_NOHTMLBLOCKS                0x0020  /* Disable raw HTML blocks. */
#define MD_FLAG_NOHTMLSPANS                 0x0040  /* Disable raw HTML (inline). */
#define MD_FLAG_TABLES                      0x0100  /* Enable tables extension. */
#define MD_FLAG_STRIKETHROUGH               0x0200  /* Enable strikethrough extension. */
#define MD_FLAG_PERMISSIVEWWWAUTOLINKS      0x0400  /* Enable WWW autolinks (even without any scheme prefix, if they begin with 'www.') */
#define MD_FLAG_TASKLISTS                   0x0800  /* Enable task list extension. */
#define MD_FLAG_LATEXMATHSPANS              0x1000  /* Enable $ and $$ containing LaTeX equations. */
#define MD_FLAG_WIKILINKS                   0x2000  /* Enable wiki links extension. */
#define MD_FLAG_UNDERLINE                   0x4000  /* Enable underline extension (and disables '_' for normal emphasis). */
#define MD_FLAG_ITALIC                      0x8000  /* Enable italic (/foo/) extension. */
#define MD_FLAG_BOLD                        0x10000 /* Enable bold extension */
#define MD_FLAG_BOX                         0x20000 /* Enable box extension */
#define MD_FLAG_HIGHLIGHT                   0x40000 /* Enable highlight extension */
#define MD_FLAG_INDENT                      0x80000 /* Enable indent extension */

#define MD_FLAG_PERMISSIVEAUTOLINKS         (MD_FLAG_PERMISSIVEEMAILAUTOLINKS | MD_FLAG_PERMISSIVEURLAUTOLINKS | MD_FLAG_PERMISSIVEWWWAUTOLINKS)
#define MD_FLAG_NOHTML                      (MD_FLAG_NOHTMLBLOCKS | MD_FLAG_NOHTMLSPANS)

/* Convenient sets of flags corresponding to well-known Markdown dialects.
 *
 * Note we may only support subset of features of the referred dialect.
 * The constant just enables those extensions which bring us as close as
 * possible given what features we implement.
 *
 * ABI compatibility note: Meaning of these can change in time as new
 * extensions, bringing the dialect closer to the original, are implemented.
 */
#define MD_DIALECT_COMMONMARK               0
#define MD_DIALECT_GITHUB                   (MD_FLAG_PERMISSIVEAUTOLINKS | MD_FLAG_TABLES | MD_FLAG_STRIKETHROUGH | MD_FLAG_TASKLISTS)

/* Parser structure.
 */
typedef struct MD_PARSER {
    /* Reserved. Set to zero.
     */
    unsigned abi_version;

    /* Dialect options. Bitmask of MD_FLAG_xxxx values.
     */
    unsigned flags;

    /* Caller-provided rendering callbacks.
     *
     * For some block/span types, more detailed information is provided in a
     * type-specific structure pointed by the argument 'detail'.
     *
     * The last argument of all callbacks, 'userdata', is just propagated from
     * md_parse() and is available for any use by the application.
     *
     * Note any strings provided to the callbacks as their arguments or as
     * members of any detail structure are generally not zero-terminated.
     * Application has to take the respective size information into account.
     *
     * Any rendering callback may abort further parsing of the document by
     * returning non-zero.
     */
    int (*enter_block)(MD_BLOCKTYPE /*type*/, void* /*detail*/, void* /*userdata*/);
    int (*leave_block)(MD_BLOCKTYPE /*type*/, void* /*detail*/, void* /*userdata*/);

    int (*enter_span)(MD_SPANTYPE /*type*/, void* /*detail*/, void* /*userdata*/);
    int (*leave_span)(MD_SPANTYPE /*type*/, void* /*detail*/, void* /*userdata*/);

    int (*text)(MD_TEXTTYPE /*type*/, const MD_CHAR* /*text*/, MD_SIZE /*size*/, void* /*userdata*/);

    /* Debug callback. Optional (may be NULL).
     *
     * If provided and something goes wrong, this function gets called.
     * This is intended for debugging and problem diagnosis for developers;
     * it is not intended to provide any errors suitable for displaying to an
     * end user.
     */
    void (*debug_log)(const char* /*msg*/, void* /*userdata*/);

    /* Reserved. Set to NULL.
     */
    void (*syntax)(void);
} MD_PARSER;


/* For backward compatibility. Do not use in new code.
 */
typedef MD_PARSER MD_RENDERER;


/* Parse the Markdown document stored in the string 'text' of size 'size'.
 * The parser provides callbacks to be called during the parsing so the
 * caller can render the document on the screen or convert the Markdown
 * to another format.
 *
 * Zero is returned on success. If a runtime error occurs (e.g. a memory
 * fails), -1 is returned. If the processing is aborted due any callback
 * returning non-zero, the return value of the callback is returned.
 */
int md_parse(const MD_CHAR* text, MD_SIZE size, const MD_PARSER* parser, void* userdata);


#ifdef __cplusplus
    }  /* extern "C" { */
#endif

#endif  /* MD4C_H */