Let a Lua script write while it loads

A script's top level runs before cgit hooks stdout for it, and the
unhook html() began with tripped an assert that aborted cgit.

2 files changed, 26 insertions, 2 deletions

diff --git a/source/filter.c b/source/filter.cindex ec48007..b36f03e 100644--- a/source/filter.c+++ b/source/filter.c@@ -225,15 +225,19 @@ static inline int emit_unfiltered(lua_State *lua_state, void (*emit)(const char 	if (!text) 		return 0; +	// A script that writes while it is still loading runs before cgit has+	// hooked stdout for it, so there is no hook to take off. 	saved_write = filter_write; 	saved_filter = current_write_filter;-	unhook_write();+	if (saved_write)+		unhook_write(); 	emit(text); 	// emit leaves bytes in the html buffer, so empty it while the hook is 	// still off. Re-hooking first would send the page's own bytes back into 	// the filter. 	html_flush();-	hook_write(saved_filter, saved_write);+	if (saved_write)+		hook_write(saved_filter, saved_write);  	return 0; }
diff --git a/source/filter.c b/source/filter.c
index ec48007..b36f03e 100644
--- a/source/filter.c
+++ b/source/filter.c
@@ -225,15 +225,19 @@ static inline int emit_unfiltered(lua_State *lua_state, void (*emit)(const char
 	if (!text)
 		return 0;
 
+	// A script that writes while it is still loading runs before cgit has
+	// hooked stdout for it, so there is no hook to take off.
 	saved_write = filter_write;
 	saved_filter = current_write_filter;
-	unhook_write();
+	if (saved_write)
+		unhook_write();
 	emit(text);
 	// emit leaves bytes in the html buffer, so empty it while the hook is
 	// still off. Re-hooking first would send the page's own bytes back into
 	// the filter.
 	html_flush();
-	hook_write(saved_filter, saved_write);
+	if (saved_write)
+		hook_write(saved_filter, saved_write);
 
 	return 0;
 }
diff --git a/tests/t0201-filters.sh b/tests/t0201-filters.shindex 1dd0910..c2d0ec4 100755--- a/tests/t0201-filters.sh+++ b/tests/t0201-filters.sh@@ -130,4 +130,24 @@ test_expect_success CGIT_LUA 'a failing lua filter still renders an error page' 	grep "Lua error in" err ' +# A script runs its top level before cgit hooks stdout for it, so what it+# writes there goes straight onto the page instead of tripping the hook.+test_expect_success CGIT_LUA 'a lua filter that writes while loading still renders' '+	cat >loud.lua <<-\EOF &&+	html("written while loading")+	function filter_open(...) end+	function filter_write(str) html(str) end+	function filter_close() return 0 end+	EOF+	{+		echo "cache-size=0" &&+		echo "repo.url=foo" &&+		echo "repo.path=$PWD/repos/foo/.git" &&+		echo "repo.commit-filter=lua:$PWD/loud.lua"+	} >loudrc &&+	CGIT_CONFIG="$PWD/loudrc" QUERY_STRING="url=foo/commit" cgit >tmp &&+	grep "written while loading" tmp &&+	grep "</html>" tmp+'+ test_done
diff --git a/tests/t0201-filters.sh b/tests/t0201-filters.sh
index 1dd0910..c2d0ec4 100755
--- a/tests/t0201-filters.sh
+++ b/tests/t0201-filters.sh
@@ -130,4 +130,24 @@ test_expect_success CGIT_LUA 'a failing lua filter still renders an error page'
 	grep "Lua error in" err
 '
 
+# A script runs its top level before cgit hooks stdout for it, so what it
+# writes there goes straight onto the page instead of tripping the hook.
+test_expect_success CGIT_LUA 'a lua filter that writes while loading still renders' '
+	cat >loud.lua <<-\EOF &&
+	html("written while loading")
+	function filter_open(...) end
+	function filter_write(str) html(str) end
+	function filter_close() return 0 end
+	EOF
+	{
+		echo "cache-size=0" &&
+		echo "repo.url=foo" &&
+		echo "repo.path=$PWD/repos/foo/.git" &&
+		echo "repo.commit-filter=lua:$PWD/loud.lua"
+	} >loudrc &&
+	CGIT_CONFIG="$PWD/loudrc" QUERY_STRING="url=foo/commit" cgit >tmp &&
+	grep "written while loading" tmp &&
+	grep "</html>" tmp
+'
+
 test_done