From 898d470f90e4055d0bcfe616bc009cca8d7f5692 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Paul=20H=C3=A4nsch?= <paul@plutz.net>
Date: Fri, 30 Aug 2024 21:59:59 +0200
Subject: [PATCH] optimized emphasis regex for performance in mawk
---
markdown.awk | 17 +++++++++--------
1 file changed, 9 insertions(+), 8 deletions(-)
diff --git a/markdown.awk b/markdown.awk
index 6e3febe..6e1440c 100755
--- a/markdown.awk
+++ b/markdown.awk
@@ -307,6 +307,7 @@ function inline( line, LOCAL, len, text, code, href, guard, ret ) {
ret = ret HTML(substr( line, 1, RLENGTH)); line = substr(line, RLENGTH + 1);
continue;
+ # strong / em matchers use pre match pattern to make processing cheaper
# __strong__$
} else if ( match(line, "^__(([^_[:space:]]|" ieu ")|([^_[:space:]]|" ieu ")(" nu "|" ieu ")*([^_[:space:]]|" ieu "))__$") ) {
len = RLENGTH;
@@ -320,7 +321,7 @@ function inline( line, LOCAL, len, text, code, href, guard, ret ) {
continue;
# **strong**
- } else if ( match(line, "^\\*\\*(([^\\*[:space:]]|" iea ")|([^\\*[:space:]]|" iea ")(" na "|" iea ")*([^\\*[:space:]]|" iea "))\\*\\*") ) {
+ } else if ( match(line, "^\\*\\*(([^*[:space:]]|" iea ")|([^*[:space:]]|" iea ")(" na "|" iea ")*([^*[:space:]]|" iea "))\\*\\*") ) {
len = RLENGTH;
ret = ret "<strong>" inline( substr( line, 3, len - 4 ) ) "</strong>"; line = substr( line, len + 1 );
continue;
@@ -338,7 +339,7 @@ function inline( line, LOCAL, len, text, code, href, guard, ret ) {
continue;
# *em*
- } else if ( match(line, "^\\*(([^\\*[:space:]]|" isa ")|([^\\*[:space:]]|" isa ")(" na "|" isa ")*([^\\*[:space:]]|" isa "))\\*") ) {
+ } else if ( match(line, "^\\*(([^*[:space:]]|" isa ")|([^*[:space:]]|" isa ")(" na "|" isa ")*([^*[:space:]]|" isa "))\\*") ) {
len = RLENGTH;
ret = ret "<em>" inline( substr( line, 2, len - 2 ) ) "</em>"; line = substr( line, len + 1 );
continue;
@@ -944,12 +945,12 @@ BEGIN {
# hls = "0 0 0 0 0 0";
# Universal Patterns
- nu = "(\\\\\\\\|\\\\[^\\\\]|[^\\\\_]|_[[:alnum:]])*" # not underline (except when escaped)
- na = "(\\\\\\\\|\\\\[^\\\\]|[^\\\\\\*])*" # not asterisk (except when escaped)
- ieu = "_([^_[:space:]]|[^_[:space:]]" nu "[^_[:space:]])_" # inner <em> (underline)
- isu = "__([^_[:space:]]|[^_[:space:]]" nu "[^_[:space:]])__" # inner <strong> (underline)
- iea = "\\*([^\\*[:space:]]|[^\\*[:space:]]" na "[^\\*[:space:]])\\*" # inner <em> (asterisk)
- isa = "\\*\\*([^\\*[:space:]]|[^\\*[:space:]]" na "[^\\*[:space:]])\\*\\*" # inner <strong> (asterisk)
+ nu = "([^_\\\\]|\\\\.|_[[:alnum:]])" # not underline (except when escaped, or inside a word)
+ na = "([^*\\\\]|\\\\.)" # not asterisk (except when escaped)
+ ieu = "_([^_[:space:]]|[^_[:space:]]" nu "*[^_[:space:]])_" # inner <em> (underline)
+ isu = "__([^_[:space:]]|[^_[:space:]]" nu "*[^_[:space:]])__" # inner <strong> (underline)
+ iea = "\\*([^*[:space:]]|[^*[:space:]]" na "*[^*[:space:]])\\*" # inner <em> (asterisk)
+ isa = "\\*\\*([^*[:space:]]|[^*[:space:]]" na "*[^*[:space:]])\\*\\*" # inner <strong> (asterisk)
lix="\\[(\\\\[^\n]|[^]\n\\\\[])*\\]" # link text
lid="(<(\\\\[^\n]|[^\n<>\\\\])*>|(\\\\.|[^()\"'\\\\])+|([^<\n\t ()\\\\]|\\\\[^\n])(\\\\[\n]|[^\n\t \\(\\)\\\\])*)" # link dest
--
2.39.5