pdf2swf/xpdf/XRef.h

   1 //========================================================================
   2 //
   3 // XRef.h
   4 //
   5 // Copyright 1996-2002 Glyph & Cog, LLC
   6 //
   7 //========================================================================
   8
   9 #ifndef XREF_H
  10 #define XREF_H
  11
  12 #ifdef __GNUC__
  13 #pragma interface
  14 #endif
  15
  16 #include "gtypes.h"
  17 #include "Object.h"
  18
  19 class Dict;
  20 class Stream;
  21
  22 //------------------------------------------------------------------------
  23 // XRef
  24 //------------------------------------------------------------------------
  25
  26 struct XRefEntry {
  27   Guint offset;
  28   int gen;
  29   GBool used;
  30 };
  31
  32 class XRef {
  33 public:
  34
  35   // Constructor.  Read xref table from stream.
  36   XRef(BaseStream *strA, GString *ownerPassword, GString *userPassword);
  37
  38   // Destructor.
  39   ~XRef();
  40
  41   // Is xref table valid?
  42   GBool isOk() { return ok; }
  43
  44   // Get the error code (if isOk() returns false).
  45   int getErrorCode() { return errCode; }
  46
  47   // Is the file encrypted?
  48 #ifndef NO_DECRYPTION
  49   GBool isEncrypted() { return encrypted; }
  50 #else
  51   GBool isEncrypted() { return gFalse; }
  52 #endif
  53
  54   // Check various permissions.
  55   GBool okToPrint(GBool ignoreOwnerPW = gFalse);
  56   GBool okToChange(GBool ignoreOwnerPW = gFalse);
  57   GBool okToCopy(GBool ignoreOwnerPW = gFalse);
  58   GBool okToAddNotes(GBool ignoreOwnerPW = gFalse);
  59
  60   // Get catalog object.
  61   Object *getCatalog(Object *obj) { return fetch(rootNum, rootGen, obj); }
  62
  63   // Fetch an indirect reference.
  64   Object *fetch(int num, int gen, Object *obj);
  65
  66   // Return the document's Info dictionary (if any).
  67   Object *getDocInfo(Object *obj);
  68   Object *getDocInfoNF(Object *obj);
  69
  70   // Return the number of objects in the xref table.
  71   int getNumObjects() { return size; }
  72
  73   // Return the offset of the last xref table.
  74   Guint getLastXRefPos() { return lastXRefPos; }
  75
  76   // Return the catalog object reference.
  77   int getRootNum() { return rootNum; }
  78   int getRootGen() { return rootGen; }
  79
  80   // Get end position for a stream in a damaged file.
  81   // Returns false if unknown or file is not damaged.
  82   GBool getStreamEnd(Guint streamStart, Guint *streamEnd);
  83
  84 private:
  85
  86   BaseStream *str;              // input stream
  87   Guint start;                  // offset in file (to allow for garbage
  88                                 //   at beginning of file)
  89   XRefEntry *entries;           // xref entries
  90   int size;                     // size of <entries> array
  91   int rootNum, rootGen;         // catalog dict
  92   GBool ok;                     // true if xref table is valid
  93   int errCode;                  // error code (if <ok> is false)
  94   Object trailerDict;           // trailer dictionary
  95   Guint lastXRefPos;            // offset of last xref table
  96   Guint *streamEnds;            // 'endstream' positions - only used in
  97                                 //   damaged files
  98   int streamEndsLen;            // number of valid entries in streamEnds
  99 #ifndef NO_DECRYPTION
 100   GBool encrypted;              // true if file is encrypted
 101   int encVersion;               // encryption algorithm
 102   int encRevision;              // security handler revision
 103   int keyLength;                // length of key, in bytes
 104   int permFlags;                // permission bits
 105   Guchar fileKey[16];           // file decryption key
 106   GBool ownerPasswordOk;        // true if owner password is correct
 107 #endif
 108
 109   Guint readTrailer();
 110   GBool readXRef(Guint *pos);
 111   GBool constructXRef();
 112   GBool checkEncrypted(GString *ownerPassword, GString *userPassword);
 113   Guint strToUnsigned(char *s);
 114 };
 115
 116 #endif