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Diffstat (limited to 'src/md4c-html.c')
| -rw-r--r-- | src/md4c-html.c | 573 |
1 files changed, 0 insertions, 573 deletions
diff --git a/src/md4c-html.c b/src/md4c-html.c deleted file mode 100644 index d604aec..0000000 --- a/src/md4c-html.c +++ /dev/null @@ -1,573 +0,0 @@ -/* - * MD4C: Markdown parser for C - * (http://github.com/mity/md4c) - * - * Copyright (c) 2016-2019 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. - */ - -#include <stdio.h> -#include <string.h> - -#include "md4c-html.h" -#include "entity.h" - - -#if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 199409L - /* C89/90 or old compilers in general may not understand "inline". */ - #if defined __GNUC__ - #define inline __inline__ - #elif defined _MSC_VER - #define inline __inline - #else - #define inline - #endif -#endif - -#ifdef _WIN32 - #define snprintf _snprintf -#endif - - - -typedef struct MD_HTML_tag MD_HTML; -struct MD_HTML_tag { - void (*process_output)(const MD_CHAR*, MD_SIZE, void*); - void* userdata; - unsigned flags; - int image_nesting_level; - char escape_map[256]; -}; - -#define NEED_HTML_ESC_FLAG 0x1 -#define NEED_URL_ESC_FLAG 0x2 - - -/***************************************** - *** HTML rendering helper functions *** - *****************************************/ - -#define ISDIGIT(ch) ('0' <= (ch) && (ch) <= '9') -#define ISLOWER(ch) ('a' <= (ch) && (ch) <= 'z') -#define ISUPPER(ch) ('A' <= (ch) && (ch) <= 'Z') -#define ISALNUM(ch) (ISLOWER(ch) || ISUPPER(ch) || ISDIGIT(ch)) - - -static inline void -render_verbatim(MD_HTML* r, const MD_CHAR* text, MD_SIZE size) -{ - r->process_output(text, size, r->userdata); -} - -/* Keep this as a macro. Most compiler should then be smart enough to replace - * the strlen() call with a compile-time constant if the string is a C literal. */ -#define RENDER_VERBATIM(r, verbatim) \ - render_verbatim((r), (verbatim), (MD_SIZE) (strlen(verbatim))) - - -static void -render_html_escaped(MD_HTML* r, const MD_CHAR* data, MD_SIZE size) -{ - MD_OFFSET beg = 0; - MD_OFFSET off = 0; - - /* Some characters need to be escaped in normal HTML text. */ - #define NEED_HTML_ESC(ch) (r->escape_map[(unsigned char)(ch)] & NEED_HTML_ESC_FLAG) - - while(1) { - /* Optimization: Use some loop unrolling. */ - while(off + 3 < size && !NEED_HTML_ESC(data[off+0]) && !NEED_HTML_ESC(data[off+1]) - && !NEED_HTML_ESC(data[off+2]) && !NEED_HTML_ESC(data[off+3])) - off += 4; - while(off < size && !NEED_HTML_ESC(data[off])) - off++; - - if(off > beg) - render_verbatim(r, data + beg, off - beg); - - if(off < size) { - switch(data[off]) { - case '&': RENDER_VERBATIM(r, "&"); break; - case '<': RENDER_VERBATIM(r, "<"); break; - case '>': RENDER_VERBATIM(r, ">"); break; - case '"': RENDER_VERBATIM(r, """); break; - } - off++; - } else { - break; - } - beg = off; - } -} - -static void -render_url_escaped(MD_HTML* r, const MD_CHAR* data, MD_SIZE size) -{ - static const MD_CHAR hex_chars[] = "0123456789ABCDEF"; - MD_OFFSET beg = 0; - MD_OFFSET off = 0; - - /* Some characters need to be escaped in URL attributes. */ - #define NEED_URL_ESC(ch) (r->escape_map[(unsigned char)(ch)] & NEED_URL_ESC_FLAG) - - while(1) { - while(off < size && !NEED_URL_ESC(data[off])) - off++; - if(off > beg) - render_verbatim(r, data + beg, off - beg); - - if(off < size) { - char hex[3]; - - switch(data[off]) { - case '&': RENDER_VERBATIM(r, "&"); break; - default: - hex[0] = '%'; - hex[1] = hex_chars[((unsigned)data[off] >> 4) & 0xf]; - hex[2] = hex_chars[((unsigned)data[off] >> 0) & 0xf]; - render_verbatim(r, hex, 3); - break; - } - off++; - } else { - break; - } - - beg = off; - } -} - -static unsigned -hex_val(char ch) -{ - if('0' <= ch && ch <= '9') - return ch - '0'; - if('A' <= ch && ch <= 'Z') - return ch - 'A' + 10; - else - return ch - 'a' + 10; -} - -static void -render_utf8_codepoint(MD_HTML* r, unsigned codepoint, - void (*fn_append)(MD_HTML*, const MD_CHAR*, MD_SIZE)) -{ - static const MD_CHAR utf8_replacement_char[] = { 0xef, 0xbf, 0xbd }; - - unsigned char utf8[4]; - size_t n; - - if(codepoint <= 0x7f) { - n = 1; - utf8[0] = codepoint; - } else if(codepoint <= 0x7ff) { - n = 2; - utf8[0] = 0xc0 | ((codepoint >> 6) & 0x1f); - utf8[1] = 0x80 + ((codepoint >> 0) & 0x3f); - } else if(codepoint <= 0xffff) { - n = 3; - utf8[0] = 0xe0 | ((codepoint >> 12) & 0xf); - utf8[1] = 0x80 + ((codepoint >> 6) & 0x3f); - utf8[2] = 0x80 + ((codepoint >> 0) & 0x3f); - } else { - n = 4; - utf8[0] = 0xf0 | ((codepoint >> 18) & 0x7); - utf8[1] = 0x80 + ((codepoint >> 12) & 0x3f); - utf8[2] = 0x80 + ((codepoint >> 6) & 0x3f); - utf8[3] = 0x80 + ((codepoint >> 0) & 0x3f); - } - - if(0 < codepoint && codepoint <= 0x10ffff) - fn_append(r, (char*)utf8, (MD_SIZE)n); - else - fn_append(r, utf8_replacement_char, 3); -} - -/* Translate entity to its UTF-8 equivalent, or output the verbatim one - * if such entity is unknown (or if the translation is disabled). */ -static void -render_entity(MD_HTML* r, const MD_CHAR* text, MD_SIZE size, - void (*fn_append)(MD_HTML*, const MD_CHAR*, MD_SIZE)) -{ - if(r->flags & MD_HTML_FLAG_VERBATIM_ENTITIES) { - render_verbatim(r, text, size); - return; - } - - /* We assume UTF-8 output is what is desired. */ - if(size > 3 && text[1] == '#') { - unsigned codepoint = 0; - - if(text[2] == 'x' || text[2] == 'X') { - /* Hexadecimal entity (e.g. "�")). */ - MD_SIZE i; - for(i = 3; i < size-1; i++) - codepoint = 16 * codepoint + hex_val(text[i]); - } else { - /* Decimal entity (e.g. "&1234;") */ - MD_SIZE i; - for(i = 2; i < size-1; i++) - codepoint = 10 * codepoint + (text[i] - '0'); - } - - render_utf8_codepoint(r, codepoint, fn_append); - return; - } else { - /* Named entity (e.g. " "). */ - const struct entity* ent; - - ent = entity_lookup(text, size); - if(ent != NULL) { - render_utf8_codepoint(r, ent->codepoints[0], fn_append); - if(ent->codepoints[1]) - render_utf8_codepoint(r, ent->codepoints[1], fn_append); - return; - } - } - - fn_append(r, text, size); -} - -static void -render_attribute(MD_HTML* r, const MD_ATTRIBUTE* attr, - void (*fn_append)(MD_HTML*, const MD_CHAR*, MD_SIZE)) -{ - int i; - - for(i = 0; attr->substr_offsets[i] < attr->size; i++) { - MD_TEXTTYPE type = attr->substr_types[i]; - MD_OFFSET off = attr->substr_offsets[i]; - MD_SIZE size = attr->substr_offsets[i+1] - off; - const MD_CHAR* text = attr->text + off; - - switch(type) { - case MD_TEXT_NULLCHAR: render_utf8_codepoint(r, 0x0000, render_verbatim); break; - case MD_TEXT_ENTITY: render_entity(r, text, size, fn_append); break; - default: fn_append(r, text, size); break; - } - } -} - - -static void -render_open_ol_block(MD_HTML* r, const MD_BLOCK_OL_DETAIL* det) -{ - char buf[64]; - - if(det->start == 1) { - RENDER_VERBATIM(r, "<ol>\n"); - return; - } - - snprintf(buf, sizeof(buf), "<ol start=\"%u\">\n", det->start); - RENDER_VERBATIM(r, buf); -} - -static void -render_open_li_block(MD_HTML* r, const MD_BLOCK_LI_DETAIL* det) -{ - if(det->is_task) { - RENDER_VERBATIM(r, "<li class=\"task-list-item\">" - "<input type=\"checkbox\" class=\"task-list-item-checkbox\" disabled"); - if(det->task_mark == 'x' || det->task_mark == 'X') - RENDER_VERBATIM(r, " checked"); - RENDER_VERBATIM(r, ">"); - } else { - RENDER_VERBATIM(r, "<li>"); - } -} - -static void -render_open_code_block(MD_HTML* r, const MD_BLOCK_CODE_DETAIL* det) -{ - RENDER_VERBATIM(r, "<pre><code"); - - /* If known, output the HTML 5 attribute class="language-LANGNAME". */ - if(det->lang.text != NULL) { - RENDER_VERBATIM(r, " class=\"language-"); - render_attribute(r, &det->lang, render_html_escaped); - RENDER_VERBATIM(r, "\""); - } - - RENDER_VERBATIM(r, ">"); -} - -static void -render_open_td_block(MD_HTML* r, const MD_CHAR* cell_type, const MD_BLOCK_TD_DETAIL* det) -{ - RENDER_VERBATIM(r, "<"); - RENDER_VERBATIM(r, cell_type); - - switch(det->align) { - case MD_ALIGN_LEFT: RENDER_VERBATIM(r, " align=\"left\">"); break; - case MD_ALIGN_CENTER: RENDER_VERBATIM(r, " align=\"center\">"); break; - case MD_ALIGN_RIGHT: RENDER_VERBATIM(r, " align=\"right\">"); break; - default: RENDER_VERBATIM(r, ">"); break; - } -} - -static void -render_open_a_span(MD_HTML* r, const MD_SPAN_A_DETAIL* det) -{ - RENDER_VERBATIM(r, "<a href=\""); - render_attribute(r, &det->href, render_url_escaped); - - if(det->title.text != NULL) { - RENDER_VERBATIM(r, "\" title=\""); - render_attribute(r, &det->title, render_html_escaped); - } - - RENDER_VERBATIM(r, "\">"); -} - -static void -render_open_img_span(MD_HTML* r, const MD_SPAN_IMG_DETAIL* det) -{ - RENDER_VERBATIM(r, "<img src=\""); - render_attribute(r, &det->src, render_url_escaped); - - RENDER_VERBATIM(r, "\" alt=\""); - - r->image_nesting_level++; -} - -static void -render_close_img_span(MD_HTML* r, const MD_SPAN_IMG_DETAIL* det) -{ - if(det->title.text != NULL) { - RENDER_VERBATIM(r, "\" title=\""); - render_attribute(r, &det->title, render_html_escaped); - } - - RENDER_VERBATIM(r, (r->flags & MD_HTML_FLAG_XHTML) ? "\" />" : "\">"); - - r->image_nesting_level--; -} - -static void -render_open_wikilink_span(MD_HTML* r, const MD_SPAN_WIKILINK_DETAIL* det) -{ - RENDER_VERBATIM(r, "<x-wikilink data-target=\""); - render_attribute(r, &det->target, render_html_escaped); - - RENDER_VERBATIM(r, "\">"); -} - - -/************************************** - *** HTML renderer implementation *** - **************************************/ - -static int -enter_block_callback(MD_BLOCKTYPE type, void* detail, void* userdata) -{ - static const MD_CHAR* head[6] = { "<h1>", "<h2>", "<h3>", "<h4>", "<h5>", "<h6>" }; - MD_HTML* r = (MD_HTML*) userdata; - - switch(type) { - case MD_BLOCK_DOC: /* noop */ break; - case MD_BLOCK_QUOTE: RENDER_VERBATIM(r, "<blockquote>\n"); break; - case MD_BLOCK_UL: RENDER_VERBATIM(r, "<ul>\n"); break; - case MD_BLOCK_OL: render_open_ol_block(r, (const MD_BLOCK_OL_DETAIL*)detail); break; - case MD_BLOCK_LI: render_open_li_block(r, (const MD_BLOCK_LI_DETAIL*)detail); break; - case MD_BLOCK_HR: RENDER_VERBATIM(r, (r->flags & MD_HTML_FLAG_XHTML) ? "<hr />\n" : "<hr>\n"); break; - case MD_BLOCK_H: RENDER_VERBATIM(r, head[((MD_BLOCK_H_DETAIL*)detail)->level - 1]); break; - case MD_BLOCK_CODE: render_open_code_block(r, (const MD_BLOCK_CODE_DETAIL*) detail); break; - case MD_BLOCK_HTML: /* noop */ break; - case MD_BLOCK_P: RENDER_VERBATIM(r, "<p>"); break; - case MD_BLOCK_TABLE: RENDER_VERBATIM(r, "<table>\n"); break; - case MD_BLOCK_THEAD: RENDER_VERBATIM(r, "<thead>\n"); break; - case MD_BLOCK_TBODY: RENDER_VERBATIM(r, "<tbody>\n"); break; - case MD_BLOCK_TR: RENDER_VERBATIM(r, "<tr>\n"); break; - case MD_BLOCK_TH: render_open_td_block(r, "th", (MD_BLOCK_TD_DETAIL*)detail); break; - case MD_BLOCK_TD: render_open_td_block(r, "td", (MD_BLOCK_TD_DETAIL*)detail); break; - } - - return 0; -} - -static int -leave_block_callback(MD_BLOCKTYPE type, void* detail, void* userdata) -{ - static const MD_CHAR* head[6] = { "</h1>\n", "</h2>\n", "</h3>\n", "</h4>\n", "</h5>\n", "</h6>\n" }; - MD_HTML* r = (MD_HTML*) userdata; - - switch(type) { - case MD_BLOCK_DOC: /*noop*/ break; - case MD_BLOCK_QUOTE: RENDER_VERBATIM(r, "</blockquote>\n"); break; - case MD_BLOCK_UL: RENDER_VERBATIM(r, "</ul>\n"); break; - case MD_BLOCK_OL: RENDER_VERBATIM(r, "</ol>\n"); break; - case MD_BLOCK_LI: RENDER_VERBATIM(r, "</li>\n"); break; - case MD_BLOCK_HR: /*noop*/ break; - case MD_BLOCK_H: RENDER_VERBATIM(r, head[((MD_BLOCK_H_DETAIL*)detail)->level - 1]); break; - case MD_BLOCK_CODE: RENDER_VERBATIM(r, "</code></pre>\n"); break; - case MD_BLOCK_HTML: /* noop */ break; - case MD_BLOCK_P: RENDER_VERBATIM(r, "</p>\n"); break; - case MD_BLOCK_TABLE: RENDER_VERBATIM(r, "</table>\n"); break; - case MD_BLOCK_THEAD: RENDER_VERBATIM(r, "</thead>\n"); break; - case MD_BLOCK_TBODY: RENDER_VERBATIM(r, "</tbody>\n"); break; - case MD_BLOCK_TR: RENDER_VERBATIM(r, "</tr>\n"); break; - case MD_BLOCK_TH: RENDER_VERBATIM(r, "</th>\n"); break; - case MD_BLOCK_TD: RENDER_VERBATIM(r, "</td>\n"); break; - } - - return 0; -} - -static int -enter_span_callback(MD_SPANTYPE type, void* detail, void* userdata) -{ - MD_HTML* r = (MD_HTML*) userdata; - - if(r->image_nesting_level > 0) { - /* We are inside a Markdown image label. Markdown allows to use any - * emphasis and other rich contents in that context similarly as in - * any link label. - * - * However, unlike in the case of links (where that contents becomes - * contents of the <a>...</a> tag), in the case of images the contents - * is supposed to fall into the attribute alt: <img alt="...">. - * - * In that context we naturally cannot output nested HTML tags. So lets - * suppress them and only output the plain text (i.e. what falls into - * text() callback). - * - * This make-it-a-plain-text approach is the recommended practice by - * CommonMark specification (for HTML output). - */ - return 0; - } - - switch(type) { - case MD_SPAN_EM: RENDER_VERBATIM(r, "<em>"); break; - case MD_SPAN_STRONG: RENDER_VERBATIM(r, "<strong>"); break; - case MD_SPAN_U: RENDER_VERBATIM(r, "<u>"); break; - case MD_SPAN_A: render_open_a_span(r, (MD_SPAN_A_DETAIL*) detail); break; - case MD_SPAN_IMG: render_open_img_span(r, (MD_SPAN_IMG_DETAIL*) detail); break; - case MD_SPAN_CODE: RENDER_VERBATIM(r, "<code>"); break; - case MD_SPAN_DEL: RENDER_VERBATIM(r, "<del>"); break; - case MD_SPAN_LATEXMATH: RENDER_VERBATIM(r, "<x-equation>"); break; - case MD_SPAN_LATEXMATH_DISPLAY: RENDER_VERBATIM(r, "<x-equation type=\"display\">"); break; - case MD_SPAN_WIKILINK: render_open_wikilink_span(r, (MD_SPAN_WIKILINK_DETAIL*) detail); break; - } - - return 0; -} - -static int -leave_span_callback(MD_SPANTYPE type, void* detail, void* userdata) -{ - MD_HTML* r = (MD_HTML*) userdata; - - if(r->image_nesting_level > 0) { - /* Ditto as in enter_span_callback(), except we have to allow the - * end of the <img> tag. */ - if(r->image_nesting_level == 1 && type == MD_SPAN_IMG) - render_close_img_span(r, (MD_SPAN_IMG_DETAIL*) detail); - return 0; - } - - switch(type) { - case MD_SPAN_EM: RENDER_VERBATIM(r, "</em>"); break; - case MD_SPAN_STRONG: RENDER_VERBATIM(r, "</strong>"); break; - case MD_SPAN_U: RENDER_VERBATIM(r, "</u>"); break; - case MD_SPAN_A: RENDER_VERBATIM(r, "</a>"); break; - case MD_SPAN_IMG: /*noop, handled above*/ break; - case MD_SPAN_CODE: RENDER_VERBATIM(r, "</code>"); break; - case MD_SPAN_DEL: RENDER_VERBATIM(r, "</del>"); break; - case MD_SPAN_LATEXMATH: /*fall through*/ - case MD_SPAN_LATEXMATH_DISPLAY: RENDER_VERBATIM(r, "</x-equation>"); break; - case MD_SPAN_WIKILINK: RENDER_VERBATIM(r, "</x-wikilink>"); break; - } - - return 0; -} - -static int -text_callback(MD_TEXTTYPE type, const MD_CHAR* text, MD_SIZE size, void* userdata) -{ - MD_HTML* r = (MD_HTML*) userdata; - - switch(type) { - case MD_TEXT_NULLCHAR: render_utf8_codepoint(r, 0x0000, render_verbatim); break; - case MD_TEXT_BR: RENDER_VERBATIM(r, (r->image_nesting_level == 0 - ? ((r->flags & MD_HTML_FLAG_XHTML) ? "<br />\n" : "<br>\n") - : " ")); - break; - case MD_TEXT_SOFTBR: RENDER_VERBATIM(r, (r->image_nesting_level == 0 ? "\n" : " ")); break; - case MD_TEXT_HTML: render_verbatim(r, text, size); break; - case MD_TEXT_ENTITY: render_entity(r, text, size, render_html_escaped); break; - default: render_html_escaped(r, text, size); break; - } - - return 0; -} - -static void -debug_log_callback(const char* msg, void* userdata) -{ - MD_HTML* r = (MD_HTML*) userdata; - if(r->flags & MD_HTML_FLAG_DEBUG) - fprintf(stderr, "MD4C: %s\n", msg); -} - -int -md_html(const MD_CHAR* input, MD_SIZE input_size, - void (*process_output)(const MD_CHAR*, MD_SIZE, void*), - void* userdata, unsigned parser_flags, unsigned renderer_flags) -{ - MD_HTML render = { process_output, userdata, renderer_flags, 0, { 0 } }; - int i; - - MD_PARSER parser = { - 0, - parser_flags, - enter_block_callback, - leave_block_callback, - enter_span_callback, - leave_span_callback, - text_callback, - debug_log_callback, - NULL - }; - - /* Build map of characters which need escaping. */ - for(i = 0; i < 256; i++) { - unsigned char ch = (unsigned char) i; - - if(strchr("\"&<>", ch) != NULL) - render.escape_map[i] |= NEED_HTML_ESC_FLAG; - - if(!ISALNUM(ch) && strchr("~-_.+!*(),%#@?=;:/,+$", ch) == NULL) - render.escape_map[i] |= NEED_URL_ESC_FLAG; - } - - /* Consider skipping UTF-8 byte order mark (BOM). */ - if(renderer_flags & MD_HTML_FLAG_SKIP_UTF8_BOM && sizeof(MD_CHAR) == 1) { - static const MD_CHAR bom[3] = { 0xef, 0xbb, 0xbf }; - if(input_size >= sizeof(bom) && memcmp(input, bom, sizeof(bom)) == 0) { - input += sizeof(bom); - input_size -= sizeof(bom); - } - } - - return md_parse(input, input_size, &parser, (void*) &render); -} - |