From 955624d449cc4f46eb72d2594904c99873666d15 Mon Sep 17 00:00:00 2001
From: "Fletcher T. Penney" <fletcher@fletcherpenney.net>
Date: Tue, 14 Mar 2017 20:10:55 -0400
Subject: [PATCH] FIXED: Limit lines treated as ATX headers

---
 Sources/libMultiMarkdown/mmd.c       | 30 +++++++-------
 Sources/libMultiMarkdown/scanners.c  | 58 +++++++++++++++++++++++++++-
 Sources/libMultiMarkdown/scanners.h  |  1 +
 Sources/libMultiMarkdown/scanners.re | 11 ++++++
 4 files changed, 86 insertions(+), 14 deletions(-)

diff --git a/Sources/libMultiMarkdown/mmd.c b/Sources/libMultiMarkdown/mmd.c
index ee3026f..0046deb 100644
--- a/Sources/libMultiMarkdown/mmd.c
+++ b/Sources/libMultiMarkdown/mmd.c
@@ -402,22 +402,26 @@ void mmd_assign_line_type(mmd_engine * e, token * line) {
 		case HASH4:
 		case HASH5:
 		case HASH6:
-			line->type = (line->child->type - HASH1) + LINE_ATX_1;
-			line->child->type = (line->type - LINE_ATX_1) + MARKER_H1;
+			if (scan_atx(&source[line->child->start])) {
+				line->type = (line->child->type - HASH1) + LINE_ATX_1;
+				line->child->type = (line->type - LINE_ATX_1) + MARKER_H1;
 
-			// Strip trailing whitespace from '#' sequence
-			line->child->len = line->child->type - MARKER_H1 + 1;
+				// Strip trailing whitespace from '#' sequence
+				line->child->len = line->child->type - MARKER_H1 + 1;
 
-			// Strip trailing '#' sequence if present
-			if (line->child->tail->type == TEXT_NL) {
-				if ((line->child->tail->prev->type >= HASH1) &&
-					(line->child->tail->prev->type <= HASH6))
-					line->child->tail->prev->type = TEXT_EMPTY;
+				// Strip trailing '#' sequence if present
+				if (line->child->tail->type == TEXT_NL) {
+					if ((line->child->tail->prev->type >= HASH1) &&
+						(line->child->tail->prev->type <= HASH6))
+						line->child->tail->prev->type = TEXT_EMPTY;
+				} else {
+					token_describe(line->child->tail, NULL);
+					if ((line->child->tail->type >= HASH1) &&
+						(line->child->tail->type <= HASH6))
+						line->child->tail->type = TEXT_EMPTY;
+				}
 			} else {
-				token_describe(line->child->tail, NULL);
-				if ((line->child->tail->type >= HASH1) &&
-					(line->child->tail->type <= HASH6))
-					line->child->tail->type = TEXT_EMPTY;
+				line->type = LINE_PLAIN;
 			}
 			break;
 		case TEXT_NUMBER_POSS_LIST:
diff --git a/Sources/libMultiMarkdown/scanners.c b/Sources/libMultiMarkdown/scanners.c
index e2ac3d1..fe334c8 100644
--- a/Sources/libMultiMarkdown/scanners.c
+++ b/Sources/libMultiMarkdown/scanners.c
@@ -1,4 +1,4 @@
-/* Generated by re2c 0.14.3 on Tue Mar 14 12:15:24 2017 */
+/* Generated by re2c 0.14.3 on Tue Mar 14 20:07:08 2017 */
 /**
 
 	MultiMarkdown 6 -- Lightweight markup processor to produce HTML, LaTeX, and more.
@@ -9940,6 +9940,62 @@ yy824:
 	
 }
 
+size_t scan_atx(const char * c) {
+	const char * marker = NULL;
+	const char * start = c;
+
+
+{
+	char yych;
+	yych = *c;
+	switch (yych) {
+	case '\n':	goto yy827;
+	case '#':	goto yy828;
+	default:	goto yy829;
+	}
+yy827:
+	{ return 0; }
+yy828:
+	yych = *(marker = ++c);
+	switch (yych) {
+	case '\t':
+	case ' ':	goto yy830;
+	case '#':	goto yy833;
+	default:	goto yy827;
+	}
+yy829:
+	yych = *++c;
+	goto yy827;
+yy830:
+	++c;
+	yych = *c;
+	switch (yych) {
+	case 0x00:
+	case '\n':
+	case '\r':	goto yy832;
+	case '\t':
+	case ' ':	goto yy830;
+	default:	goto yy835;
+	}
+yy832:
+	c = marker;
+	goto yy827;
+yy833:
+	++c;
+	yych = *c;
+	switch (yych) {
+	case '\t':
+	case ' ':	goto yy830;
+	case '#':	goto yy833;
+	default:	goto yy832;
+	}
+yy835:
+	++c;
+	{ return (size_t)( c - start ); }
+}
+	
+}
+
 
 #ifdef TEST
 void Test_scan_url(CuTest* tc) {
diff --git a/Sources/libMultiMarkdown/scanners.h b/Sources/libMultiMarkdown/scanners.h
index c046085..cb6591c 100644
--- a/Sources/libMultiMarkdown/scanners.h
+++ b/Sources/libMultiMarkdown/scanners.h
@@ -72,6 +72,7 @@ enum alignments {
 size_t scan_alignment_string(const char * c);
 size_t scan_attr(const char * c);
 size_t scan_attributes(const char * c);
+size_t scan_atx(const char * c);
 size_t scan_definition(const char * c);
 size_t scan_destination(const char * c);
 size_t scan_email(const char * c);
diff --git a/Sources/libMultiMarkdown/scanners.re b/Sources/libMultiMarkdown/scanners.re
index 22f47b6..e891d56 100644
--- a/Sources/libMultiMarkdown/scanners.re
+++ b/Sources/libMultiMarkdown/scanners.re
@@ -158,6 +158,7 @@
 
 	setext_2	= non_indent '-'{2,} nl_eof;
 
+	atx			= '#'+ [ \t]+ [^ \t\n\r\x00];
 */
 
 
@@ -460,6 +461,16 @@ size_t scan_setext(const char * c) {
 */	
 }
 
+size_t scan_atx(const char * c) {
+	const char * marker = NULL;
+	const char * start = c;
+
+/*!re2c
+	atx			{ return (size_t)( c - start ); }
+	.?			{ return 0; }
+*/	
+}
+
 
 #ifdef TEST
 void Test_scan_url(CuTest* tc) {