From 290cc67245726ca72bb8450162cb2adc5a8c78d1 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Paul=20H=C3=A4nsch?= <paul@plutz.net>
Date: Wed, 9 Oct 2024 07:10:39 +0200
Subject: [PATCH] bugfix: avoid endless loops for some incomplete matches

---
 markdown.awk      | 15 +++++++--------
 tests-markdown.sh | 13 +++++++++++--
 2 files changed, 18 insertions(+), 10 deletions(-)

diff --git a/markdown.awk b/markdown.awk
index 356a987..bef97d1 100755
--- a/markdown.awk
+++ b/markdown.awk
@@ -372,11 +372,10 @@ function inline( line, LOCAL, len, text, code, href, guard, ret ) {
       ret = ret HTML(substr(line, 1, 1)); line = substr(line, 2);
       continue;
 
-    #  continue walk over string
-    } else {
-      ret = ret substr(line, 1, 1); line = substr(line, 2);
-      continue;
-    }
+    }  # inline patterns end
+
+    # continue walk over string
+    ret = ret substr(line, 1, 1); line = substr(line, 2);
   }
   return ret;
 }
@@ -851,10 +850,10 @@ function _block( block, LOCAL, st, len, text, title, attrib, href, guard, code,
       ret = ret _block(substr(block, 1, st - 1)) "<hr>\n"; block = substr(block, st + len);
       continue;
 
+    }  # block patterns end
+
     # Plain paragraph
-    } else {
-      return ret "<p>" inline(block) "</p>\n";
-    }
+    return ret "<p>" inline(block) "</p>\n";
   }
   return ret;
 }
diff --git a/tests-markdown.sh b/tests-markdown.sh
index a834391..6df4224 100755
--- a/tests-markdown.sh
+++ b/tests-markdown.sh
@@ -1,6 +1,6 @@
 #!/bin/sh
 
-runtimes="gawk bawk mawk goawk"
+runtimes="gawk busybox mawk goawk"
 
 BR='
 '
@@ -9,7 +9,7 @@ fail() { printf '%s\n' "$@"; exit 1; }
 
 awk() { /bin/awk "$@"; }
 md_gawk() { gawk -f markdown.awk "$@"; }
-md_bawk() { busybox awk -f markdown.awk "$@"; }
+md_busybox() { busybox awk -f markdown.awk "$@"; }
 md_mawk() { mawk -f markdown.awk "$@"; }
 md_goawk() { goawk -f markdown.awk "$@"; }
 
@@ -45,6 +45,7 @@ assert '~sub~' '<p><sub>sub</sub></p>' "subscript"
 
 assert "foo  ${BR}bar" "<p>foo<br>${BR}bar</p>" 'double space line break'
 assert '```&copy;```' "<p><code>&amp;copy;</code></p>" "code span escape"
+assert '````' "<pre><code>````</code></pre>" "empty code span"
 
 assert '_emphasized text_' '<p><em>emphasized text</em></p>' "em"
 assert '_emphasized_text_' '<p><em>emphasized_text</em></p>' "em"
@@ -190,6 +191,14 @@ not be
 but &amp;shy; &lt;escaped&gt;</code></pre>' \
 "fenced code block"
 
+assert 'foobar
+````
+foobar' \
+'<p>foobar
+````
+foobar</p>' \
+"Open Fence"
+
 # Block Images
 assert '![Testbild](Test Bild.jpg)' \
 '<figure data-src="Test Bild.jpg"><img src="Test Bild.jpg" alt="Testbild"></figure>' \
-- 
2.39.2