;;; Global constants
-(define gopher-index-file-name "index")
+(define gopher-index-filename "index")
(define burrower-version "1.0.0")
;;; Selector type inference
-(define (has-suffix? selector . suffixes)
- (if (null? suffixes)
+(define (true-for-one? predicate values)
+ (if (null? values)
#f
- (if (string-suffix? (car suffixes) selector)
+ (if (predicate (car values))
#t
- (apply has-suffix? selector (cdr suffixes)))))
+ (true-for-one? predicate (cdr values)))))
+
+(define (has-suffix? selector . suffixes)
+ (true-for-one? (lambda (suffix)
+ (string-suffix? suffix selector))
+ suffixes))
+
+(define (has-prefix? selector . prefixes)
+ (true-for-one? (lambda (prefix)
+ (string-prefix? prefix selector))
+ prefixes))
(define (infer-selector-type selector)
(let ((l (string-downcase selector)))
((has-suffix? l ".txt" ".org" ".md") 0)
((has-suffix? l ".png" ".jpg" ".gif" ".bmp" ".tif" ".tga") 'I)
((has-suffix? l "?.scm") 7)
+ ((has-prefix? l "url:" "/url:") 'h)
(else 9))))
((1) (serve-directory selector config))
((0) (serve-text-file selector config))
((7) (serve-query selector arguments config))
+ ((h) (serve-url selector config))
(else (serve-binary-file selector config)))))
+(define (legal-filename? filename config)
+ (and (string-prefix? (config-root-dir config)
+ (normalize-pathname filename))
+ (regular-file? filename)))
+
(define (serve-directory selector config)
- (let ((file-name (make-pathname (list (config-root-dir config) selector)
- gopher-index-file-name)))
- (if (regular-file? file-name)
+ (let ((filename (make-pathname (list (config-root-dir config) selector
+ gopher-index-filename))))
+ (if (legal-filename? filename config)
(begin
- (with-input-from-file file-name
+ (with-input-from-file filename
(lambda ()
(let loop ((c (peek-char)))
(if (eof-object? c)
(error "Index file not found."))))
(define (serve-text-file selector config)
- (let ((file-name (make-pathname (config-root-dir config) selector)))
- (if (regular-file? file-name)
- (with-input-from-file file-name
+ (let ((filename (make-pathname (config-root-dir config) selector)))
+ (if (legal-filename? filename config)
+ (with-input-from-file filename
(lambda ()
(for-each
(lambda (line)
(print line "\r"))
(read-lines))))
- (error "File not found." file-name))))
+ (error "File not found." filename))))
(define (serve-binary-file selector config)
- (let ((file-name (make-pathname (config-root-dir config) selector)))
- (if (regular-file? file-name)
- (with-input-from-file file-name
+ (let ((filename (make-pathname (config-root-dir config) selector)))
+ (if (legal-filename? filename config)
+ (with-input-from-file filename
(lambda ()
(let loop ((b (read-byte)))
(if (eof-object? b)
(begin
(write-byte b)
(loop (read-byte)))))))
- (error "File not found." file-name))))
+ (error "File not found." filename))))
(define (serve-query selector arguments config)
- (let ((file-name (make-pathname (config-root-dir config) selector)))
- (if (and (regular-file? file-name)
+ (let ((filename (make-pathname (config-root-dir config) selector)))
+ (if (and (legal-filename? filename config)
(= (length arguments) 1))
- (with-input-from-file file-name
+ (with-input-from-file filename
(lambda ()
(serve-info-records
(with-selector-dir
(error "Invalid query." selector arguments))))
+(define (serve-url selector config)
+ (let ((url (substring selector 4)))
+ (print
+ "If you are seeing this page, your gopher browser does not\r\n"
+ "properly support URL directory entries or cannot follow such\r\n"
+ "links. To view the link you requested, use a web browser to\r\n"
+ "open the follwing url:\r\n"
+ "\r\n"
+ url "\r\n")))
+
+
;;; Index rendering
(define (serve-info-records string)