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Diffstat (limited to 'src/markdown/md4c.h')
| -rw-r--r-- | src/markdown/md4c.h | 405 |
1 files changed, 405 insertions, 0 deletions
diff --git a/src/markdown/md4c.h b/src/markdown/md4c.h new file mode 100644 index 0000000..95f78f9 --- /dev/null +++ b/src/markdown/md4c.h @@ -0,0 +1,405 @@ +/* + * 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, + + /* <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, + + /* 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. + * (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. Ӓ + * (c) Hexadecimal entity, e.g. ካ + * + * 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 " bar') + * + * The image alt text is propagated as a normal text via the MD_PARSER::text() + * callback. However, the image title ('foo " 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]: """ (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_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_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 */ |