moved ../../pdf2swf/xpdf to .

[swftools.git] / lib / xpdf / Parser.cc

diff --git a/lib/xpdf/Parser.cc b/lib/xpdf/Parser.cc
new file mode 100644 (file)
index 0000000..af7c933
--- /dev/null
+++ b/lib/xpdf/Parser.cc
@@ -0,0 +1,214 @@
+//========================================================================
+//
+// Parser.cc
+//
+// Copyright 1996-2003 Glyph & Cog, LLC
+//
+//========================================================================
+
+#include <aconf.h>
+
+#ifdef USE_GCC_PRAGMAS
+#pragma implementation
+#endif
+
+#include <stddef.h>
+#include "Object.h"
+#include "Array.h"
+#include "Dict.h"
+#include "Parser.h"
+#include "XRef.h"
+#include "Error.h"
+#include "Decrypt.h"
+
+Parser::Parser(XRef *xrefA, Lexer *lexerA) {
+  xref = xrefA;
+  lexer = lexerA;
+  inlineImg = 0;
+  lexer->getObj(&buf1);
+  lexer->getObj(&buf2);
+}
+
+Parser::~Parser() {
+  buf1.free();
+  buf2.free();
+  delete lexer;
+}
+
+Object *Parser::getObj(Object *obj,
+                      Guchar *fileKey, int keyLength,
+                      int objNum, int objGen) {
+  char *key;
+  Stream *str;
+  Object obj2;
+  int num;
+  Decrypt *decrypt;
+  GString *s;
+  char *p;
+  int i;
+
+  // refill buffer after inline image data
+  if (inlineImg == 2) {
+    buf1.free();
+    buf2.free();
+    lexer->getObj(&buf1);
+    lexer->getObj(&buf2);
+    inlineImg = 0;
+  }
+
+  // array
+  if (buf1.isCmd("[")) {
+    shift();
+    obj->initArray(xref);
+    while (!buf1.isCmd("]") && !buf1.isEOF())
+      obj->arrayAdd(getObj(&obj2, fileKey, keyLength, objNum, objGen));
+    if (buf1.isEOF())
+      error(getPos(), "End of file inside array");
+    shift();
+
+  // dictionary or stream
+  } else if (buf1.isCmd("<<")) {
+    shift();
+    obj->initDict(xref);
+    while (!buf1.isCmd(">>") && !buf1.isEOF()) {
+      if (!buf1.isName()) {
+       error(getPos(), "Dictionary key must be a name object");
+       shift();
+      } else {
+       key = copyString(buf1.getName());
+       shift();
+       if (buf1.isEOF() || buf1.isError()) {
+         gfree(key);
+         break;
+       }
+       obj->dictAdd(key, getObj(&obj2, fileKey, keyLength, objNum, objGen));
+      }
+    }
+    if (buf1.isEOF())
+      error(getPos(), "End of file inside dictionary");
+    if (buf2.isCmd("stream")) {
+      if ((str = makeStream(obj))) {
+       obj->initStream(str);
+       if (fileKey) {
+         str->getBaseStream()->doDecryption(fileKey, keyLength,
+                                            objNum, objGen);
+       }
+      } else {
+       obj->free();
+       obj->initError();
+      }
+    } else {
+      shift();
+    }
+
+  // indirect reference or integer
+  } else if (buf1.isInt()) {
+    num = buf1.getInt();
+    shift();
+    if (buf1.isInt() && buf2.isCmd("R")) {
+      obj->initRef(num, buf1.getInt());
+      shift();
+      shift();
+    } else {
+      obj->initInt(num);
+    }
+
+  // string
+  } else if (buf1.isString() && fileKey) {
+    buf1.copy(obj);
+    s = obj->getString();
+    decrypt = new Decrypt(fileKey, keyLength, objNum, objGen);
+    for (i = 0, p = obj->getString()->getCString();
+        i < s->getLength();
+        ++i, ++p) {
+      *p = decrypt->decryptByte(*p);
+    }
+    delete decrypt;
+    shift();
+
+  // simple object
+  } else {
+    buf1.copy(obj);
+    shift();
+  }
+
+  return obj;
+}
+
+Stream *Parser::makeStream(Object *dict) {
+  Object obj;
+  BaseStream *baseStr;
+  Stream *str;
+  Guint pos, endPos, length;
+
+  // get stream start position
+  lexer->skipToNextLine();
+  pos = lexer->getPos();
+
+  // get length
+  dict->dictLookup("Length", &obj);
+  if (obj.isInt()) {
+    length = (Guint)obj.getInt();
+    obj.free();
+  } else {
+    error(getPos(), "Bad 'Length' attribute in stream");
+    obj.free();
+    return NULL;
+  }
+
+  // check for length in damaged file
+  if (xref && xref->getStreamEnd(pos, &endPos)) {
+    length = endPos - pos;
+  }
+
+  // in badly damaged PDF files, we can run off the end of the input
+  // stream immediately after the "stream" token
+  if (!lexer->getStream()) {
+    return NULL;
+  }
+  baseStr = lexer->getStream()->getBaseStream();
+
+  // skip over stream data
+  lexer->setPos(pos + length);
+
+  // refill token buffers and check for 'endstream'
+  shift();  // kill '>>'
+  shift();  // kill 'stream'
+  if (buf1.isCmd("endstream")) {
+    shift();
+  } else {
+    error(getPos(), "Missing 'endstream'");
+    // kludge for broken PDF files: just add 5k to the length, and
+    // hope its enough
+    length += 5000;
+  }
+
+  // make base stream
+  str = baseStr->makeSubStream(pos, gTrue, length, dict);
+
+  // get filters
+  str = str->addFilters(dict);
+
+  return str;
+}
+
+void Parser::shift() {
+  if (inlineImg > 0) {
+    if (inlineImg < 2) {
+      ++inlineImg;
+    } else {
+      // in a damaged content stream, if 'ID' shows up in the middle
+      // of a dictionary, we need to reset
+      inlineImg = 0;
+    }
+  } else if (buf2.isCmd("ID")) {
+    lexer->skipChar();         // skip char after 'ID' command
+    inlineImg = 1;
+  }
+  buf1.free();
+  buf1 = buf2;
+  if (inlineImg > 0)           // don't buffer inline image data
+    buf2.initNull();
+  else
+    lexer->getObj(&buf2);
+}