commit d2da226c445841b1c975722079d79344aacbf86f
parent 43bd28445b639afbd91e0155ffb5b5072c88e181
Author: Martin Mitas <mity@morous.org>
Date: Tue, 4 Oct 2016 19:48:06 +0200
Implement fenced code blocks.
Diffstat:
3 files changed, 143 insertions(+), 3 deletions(-)
diff --git a/md2html/md2html.c b/md2html/md2html.c
@@ -125,6 +125,21 @@ membuf_append_escaped(struct membuffer* buf, const char* data, MD_SIZE size)
*** HTML renderer implementation ***
**************************************/
+static void
+open_code_block(struct membuffer* out, const MD_BLOCK_CODE_DETAIL* det)
+{
+ MEMBUF_APPEND_LITERAL(out, "<pre><code");
+
+ /* If known, output the HTML 5 attribute class="language-LANGNAME". */
+ if(det->lang != NULL) {
+ MEMBUF_APPEND_LITERAL(out, " class=\"language-");
+ membuf_append_escaped(out, det->lang, det->lang_size);
+ MEMBUF_APPEND_LITERAL(out, "\"");
+ }
+
+ MEMBUF_APPEND_LITERAL(out, ">");
+}
+
static int
enter_block_callback(MD_BLOCKTYPE type, void* detail, void* userdata)
{
@@ -135,7 +150,7 @@ enter_block_callback(MD_BLOCKTYPE type, void* detail, void* userdata)
case MD_BLOCK_DOC: /* noop */ break;
case MD_BLOCK_HR: MEMBUF_APPEND_LITERAL(out, "<hr>\n"); break;
case MD_BLOCK_H: MEMBUF_APPEND_LITERAL(out, head[((MD_BLOCK_H_DETAIL*)detail)->level - 1]); break;
- case MD_BLOCK_CODE: MEMBUF_APPEND_LITERAL(out, "<pre><code>"); break;
+ case MD_BLOCK_CODE: open_code_block(out, (const MD_BLOCK_CODE_DETAIL*) detail); break;
case MD_BLOCK_P: MEMBUF_APPEND_LITERAL(out, "<p>"); break;
}
diff --git a/md4c/md4c.c b/md4c/md4c.c
@@ -81,6 +81,13 @@ struct MD_CTX_tag {
/* For MD_BLOCK_HEADER. */
unsigned header_level;
+
+ /* For MD_BLOCK_CODE (fenced). */
+ CHAR code_fence_char; /* '~' or '`' */
+ SZ code_fence_length;
+ OFF code_fence_indent;
+ OFF code_fence_info_beg;
+ OFF code_fence_info_end;
};
typedef enum MD_LINETYPE_tag MD_LINETYPE;
@@ -91,6 +98,8 @@ enum MD_LINETYPE_tag {
MD_LINE_SETEXTHEADER,
MD_LINE_SETEXTUNDERLINE,
MD_LINE_INDENTEDCODE,
+ MD_LINE_CODEFENCE,
+ MD_LINE_FENCEDCODE,
MD_LINE_TEXT
};
@@ -364,6 +373,74 @@ md_is_setext_underline(MD_CTX* ctx, OFF beg, OFF* p_end)
return 0;
}
+static int
+md_is_opening_code_fence(MD_CTX* ctx, OFF beg, OFF* p_end)
+{
+ OFF off = beg;
+
+ MD_ASSERT(CH(beg) == _T('`') || CH(beg) == _T('~'));
+
+ while(off < ctx->size && CH(off) == CH(beg))
+ off++;
+
+ /* Fence must have at least three characters. */
+ if(off - beg < 3)
+ return -1;
+
+ ctx->code_fence_length = off - beg;
+
+ /* Optionally, space(s) can follow. */
+ while(off < ctx->size && CH(off) == _T(' '))
+ off++;
+
+ /* Optionally, language info can follow. It must not contain '`'. */
+ ctx->code_fence_info_beg = off;
+ while(off < ctx->size && CH(off) != _T('`') && !ISNEWLINE(off))
+ off++;
+ if(off < ctx->size && !ISNEWLINE(off))
+ return -1;
+
+ *p_end = off;
+
+ /* Right trim of language info. */
+ while(off > ctx->code_fence_info_beg && CH(off-1) == _T(' '))
+ off--;
+ ctx->code_fence_info_end = off;
+
+ ctx->code_fence_char = CH(beg);
+ return 0;
+}
+
+static int
+md_is_closing_code_fence(MD_CTX* ctx, OFF beg, OFF* p_end)
+{
+ OFF off = beg;
+ int ret = -1;
+
+ /* Closing fence must have at least the same length and use same char as
+ * opening one. */
+ while(off < ctx->size && CH(off) == ctx->code_fence_char)
+ off++;
+ if(off - beg < ctx->code_fence_length)
+ goto out;
+
+ /* Optionally, space(s) can follow */
+ while(off < ctx->size && CH(off) == _T(' '))
+ off++;
+
+ /* But nothing more is allowed on the line. */
+ if(off < ctx->size && !ISNEWLINE(off))
+ goto out;
+
+ ret = 0;
+
+out:
+ /* Note we set *p_end even on failure: If we are not closing fence, caller
+ * would eat the line anyway without any parsing. */
+ *p_end = off;
+ return ret;
+}
+
/* Analyze type of the line and find some its properties. This serves as a
* main input for determining type and boundaries of a block. */
static void
@@ -385,6 +462,21 @@ md_analyze_line(MD_CTX* ctx, OFF beg, OFF* p_end, const MD_LINE* pivot_line, MD_
line->beg = off;
+ /* Check whether we are fenced code continuation. */
+ if(pivot_line->type == MD_LINE_FENCEDCODE || pivot_line->type == MD_LINE_CODEFENCE) {
+ /* We are another MD_LINE_FENCEDCODE unless we are closing fence
+ * which we transform into MD_LINE_BLANK. */
+ if(line->indent < ctx->code_indent_offset) {
+ if(md_is_closing_code_fence(ctx, off, &off) == 0) {
+ line->type = MD_LINE_BLANK;
+ goto done;
+ }
+ }
+
+ line->type = MD_LINE_FENCEDCODE;
+ goto done;
+ }
+
/* Check whether we are blank line.
* Note blank lines after indented code are treated as part of that block.
* If they are at the end of the block, it is discarded by caller.
@@ -428,7 +520,7 @@ md_analyze_line(MD_CTX* ctx, OFF beg, OFF* p_end, const MD_LINE* pivot_line, MD_
}
}
- /* Check whether we are setext underline. */
+ /* Check whether we are Setext underline. */
if(pivot_line->type == MD_LINE_TEXT && (CH(off) == _T('=') || CH(off) == _T('-'))) {
if(md_is_setext_underline(ctx, off, &off) == 0) {
line->type = MD_LINE_SETEXTUNDERLINE;
@@ -436,7 +528,8 @@ md_analyze_line(MD_CTX* ctx, OFF beg, OFF* p_end, const MD_LINE* pivot_line, MD_
}
}
- /* Check whether we are thematic break line. */
+ /* Check whether we are thematic break line.
+ * (Keep this after check for Setext underline as that one has higher priority). */
if(ISANYOF(off, _T("-_*"))) {
if(md_is_hr_line(ctx, off, &off) == 0) {
line->type = MD_LINE_HR;
@@ -444,6 +537,15 @@ md_analyze_line(MD_CTX* ctx, OFF beg, OFF* p_end, const MD_LINE* pivot_line, MD_
}
}
+ /* Check whether we are starting code fence. */
+ if(CH(off) == _T('`') || CH(off) == _T('~')) {
+ if(md_is_opening_code_fence(ctx, off, &off) == 0) {
+ ctx->code_fence_indent = line->indent;
+ line->type = MD_LINE_CODEFENCE;
+ goto done;
+ }
+ }
+
/* By default, we are normal text line. */
line->type = MD_LINE_TEXT;
@@ -489,6 +591,7 @@ md_process_block(MD_CTX* ctx, const MD_LINE* lines, int n_lines)
MD_BLOCKTYPE block_type;
union {
MD_BLOCK_H_DETAIL header;
+ MD_BLOCK_CODE_DETAIL code;
} det;
int ret = 0;
@@ -511,7 +614,18 @@ md_process_block(MD_CTX* ctx, const MD_LINE* lines, int n_lines)
break;
case MD_LINE_INDENTEDCODE:
+ det.code.lang = NULL;
+ det.code.lang_size = 0;
+ block_type = MD_BLOCK_CODE;
+ break;
+
+ case MD_LINE_FENCEDCODE:
block_type = MD_BLOCK_CODE;
+ if(ctx->code_fence_info_beg < ctx->code_fence_info_end)
+ det.code.lang = STR(ctx->code_fence_info_beg);
+ else
+ det.code.lang = NULL;
+ det.code.lang_size = ctx->code_fence_info_end - ctx->code_fence_info_beg;
break;
case MD_LINE_TEXT:
@@ -519,6 +633,10 @@ md_process_block(MD_CTX* ctx, const MD_LINE* lines, int n_lines)
break;
case MD_LINE_SETEXTUNDERLINE:
+ case MD_LINE_CODEFENCE:
+ /* Noop. */
+ return 0;
+
default:
MD_UNREACHABLE();
break;
diff --git a/md4c/md4c.h b/md4c/md4c.h
@@ -103,6 +103,13 @@ struct MD_BLOCK_H_DETAIL_tag {
unsigned level; /* Header level (1 - 6) */
};
+/* Detailed info for MD_BLOCK_CODE. */
+typedef struct MD_BLOCK_CODE_DETAIL_tag MD_BLOCK_CODE_DETAIL;
+struct MD_BLOCK_CODE_DETAIL_tag {
+ const MD_CHAR* lang; /* Not zero-terminated, use lang_size. */
+ MD_SIZE lang_size;
+};
+
/* Flags specifying Markdown dialect.
*
