+#!/usr/bin/newlisp
+#
+# Simple HTTP service for a directory tree. Start with:
+#
+# newlisp hobby-http.lsp -c -http -d $PORT -w $TREE
+#
+# Note that it does not make automatic file indexes of directories,
+# and it only shows the files that are there. Some files are handled
+# by their file extension, such as: .avi, .cgi, .css, .gif, .htm,
+# .html, .jpg, .js, .mov, .mp3,.mpg, .pdf, .png, .wav, .zip. Those
+# files are served with appropriate mime types, except .cgi which if
+# executable will be executed as a near CGI 1.1 script. Other files
+# are served with type "text/plain".
+
+; Exit on ^C -- not cleanly
+(signal 2 (fn (x) (write-line 2 "Exiting") (close 3) (exit 0)))
+
+; Resolve the root path
+(constant 'HERE (real-path ((match '(* "-w" ? *) (main-args)) 1)))
+
+; Map absolute path
+(define (actual PATH)
+ (if (starts-with PATH "/") (string HERE PATH) PATH))
+
+; Rewriting rules: add ".html" or "/index.html" to request path where
+; that results in an actual file.
+(define (maybe-html PATH)
+ (let ((P0 (actual PATH)) (HTML nil))
+ (if (find ".." PATH) PATH
+ true
+ (if (file? (string P0 ".html")) (string PATH ".html")
+ (file? (string P0 "/index.html"))
+ (string PATH (if (ends-with PATH "/") "" "/") "index.html")
+ PATH )
+ PATH )))
+
+; Apply rewriting rules for some requests
+(define (tag-on-html X)
+ (write-line 2 (string "> " X ))
+ (setf X (if (and (string? X) (regex "^([^\\s]+) ([^ ]+) (.+)" X 0))
+ (let ((A $1) (B $2) (C $3))
+ (format "%s %s %s\r\n" A (maybe-html B) C) X)))
+ (write-line 2 (string "< " X))
+ X)
+
+(define (filter-request X)
+ (if (starts-with X "(GET|HEAD)" 0) (tag-on-html X)
+ "GET /403.html HTTP/1.1"))
+
+(command-event filter-request)