cgit-about-filter: write through html()

1 files changed, 25 insertions, 7 deletions

diff --git a/pkgs/simple/cgit-about-filter/cgit-about-filter.lua b/pkgs/simple/cgit-about-filter/cgit-about-filter.lua
index 6e1ccdd..86468f5 100644
--- a/pkgs/simple/cgit-about-filter/cgit-about-filter.lua
+++ b/pkgs/simple/cgit-about-filter/cgit-about-filter.lua
@@ -46,6 +46,26 @@ local function url_escape(s)
     end))
 end
 
+-- cgit provides html() to Lua filters.  It writes in order with cgit's own
+-- output, which io.write's buffered stdout doesn't.  io.write is for running
+-- the filter outside of cgit.
+local emit = html or io.write
+
+-- Run md2html and return its output.
+local function md2html(markdown)
+    local input = os.tmpname()
+    local file = assert(io.open(input, "w"))
+    file:write(markdown)
+    file:close()
+    local handle = io.popen("@md2html@ --github < " .. input, "r")
+    local output = handle and handle:read("*a")
+    if handle then
+        handle:close()
+    end
+    os.remove(input)
+    return output
+end
+
 local buffer = ""
 local should_render = true
 local current_dir = "" -- Stores the directory prefix of the file being processed
@@ -85,7 +105,7 @@ end
 
 function filter_close()
     if not should_render then
-        io.write("<p><em>Error: Access Denied. Only README.md and documentation markdown files are viewable here.</em></p>")
+        emit("<p><em>Error: Access Denied. Only README.md and documentation markdown files are viewable here.</em></p>")
         return
     end
 
@@ -115,12 +135,10 @@ function filter_close()
         end
     end)
 
-    -- Pipe everything into md2html
-    local handle = io.popen("@md2html@ --github", "w")
-    if handle then
-        handle:write(processed)
-        handle:close()
+    local output = md2html(processed)
+    if output then
+        emit(output)
     else
-        io.write("<p>Error: Could not execute md2html.</p>")
+        emit("<p>Error: Could not execute md2html.</p>")
     end
 end