trailers

pitfall/pitfall/minimal-pdf.rkt

@@ -43,4 +43,9 @@ stream
 endstream
 endobj
 
+trailer
+  <<  /Root 1 0 R 
+      /Size 5
+  >>
+
 %%EOF

pitfall/pitfall/parse.rkt

@@ -88,3 +88,11 @@
 (define (pf-header num) (co-header num))
 
 (define (pf-comment text) (co-comment text))
+
+(define (pf-trailer dict)
+  (let ([h (co-dict-dict dict)])
+    (unless (and (hash-has-key? h 'Size) (hash-has-key? h 'Root))
+      (raise-argument-error 'pf-trailer
+                            "Size and Root keys are required for trailer"
+                            (hash-keys h))))
+  (co-trailer dict))

pitfall/pitfall/parser.rkt

@@ -1,7 +1,8 @@
 #lang brag
 
-pf-program : [pf-header] pf-object*
+pf-program : pf-header pf-body  pf-trailer
 pf-header : PDF-HEADER
+@pf-body : pf-object*
 @pf-object : pf-null | CHAR | BOOLEAN | INT | REAL | pf-name | pf-string | pf-array | pf-dict | pf-stream | pf-indirect-object | pf-indirect-object-ref | pf-comment
 @pf-null : NULL
 pf-name : NAME
@@ -13,4 +14,8 @@ pf-dict : /"<" /"<" (pf-dict-key pf-dict-value)* /">" /">"
 pf-stream : pf-dict STREAM-DATA
 pf-indirect-object : INT INT /"obj" pf-object /"endobj"
 pf-indirect-object-ref : INDIRECT-OBJECT-REF-TOK
-pf-comment : COMMENT
+pf-comment : COMMENT
+
+;pf-xref-table :
+
+pf-trailer : /"trailer" pf-dict

pitfall/pitfall/render.rkt

@@ -44,7 +44,11 @@
         stream
         @(loop (co-stream-data x))
         endstream}]
-      [(co-comment? x) (co-comment-text x)]
+      #;[(co-comment? x) (co-comment-text x)]
+      [(co-trailer? x) @string-append{
+        trailer
+        @(loop (co-trailer-dict x))
+        }]
       [(symbol? x) @string-append{/@(symbol->string x)}]
       [(number? x) @number->string{@x}]
       [(string? x) (bytes->string/utf-8 (string->bytes/latin-1 x))]

pitfall/pitfall/struct.rkt

@@ -8,4 +8,5 @@
 (struct co-header (string) #:transparent)
 (struct co-io (idx rev thing) #:transparent)
 (struct co-io-ref (idx rev) #:transparent)
-(struct co-comment (text) #:transparent)
+(struct co-comment (text) #:transparent)
+(struct co-trailer (dict) #:transparent)

pitfall/pitfall/tokenizer.rkt

@@ -27,7 +27,7 @@
      [(:seq "%PDF-" digits "." digits
             (:? (:: pdf-eol "%" (:>= 4 (:~ (union #\return #\newline)))))) (token 'PDF-HEADER lexeme)]
      [pdf-whitespace (token 'IGNORE lexeme #:skip? #t)]
-     [(from/stop-before "%" #\newline) (token 'COMMENT lexeme)]
+     [(from/stop-before "%" #\newline) (token 'COMMENT lexeme #:skip? #t)]
      [(:or "true" "false") (token 'BOOLEAN (equal? lexeme "true"))]
      [(:seq optional-sign digits) (token 'INT (string->number lexeme))]
      [(:seq optional-sign (:or (:seq digits "." (:? digits))
@@ -37,7 +37,7 @@
      ["null" (token 'NULL 'null)]
      [(:seq "(" (:* (:or not-right-paren substring)) ")") (token 'STRING-TOK lexeme)]
      [(:seq hex-digit hex-digit) (token 'HEX-DIGIT-PAIR (string->number lexeme 16))]
-     [(:or "<" ">" "[" "]" "obj" "endobj") (token lexeme lexeme)]
+     [(:or "<" ">" "[" "]" "obj" "endobj" "trailer") (token lexeme lexeme)]
      [(from/to "stream" "endstream") (token 'STREAM-DATA (string-trim (trim-ends "stream" lexeme "endstream") "\n"))]
      [any-char (token 'CHAR lexeme)]))
   (λ () (lex-one-token port)))