Basic support for Type3 Fonts in Pdf + various refactorings

experimental/PdfViewer/SkPdfParser.h

+/*
+ * Copyright 2013 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "podofo.h"
+#include "SkPdfHeaders_autogen.h"
+#include "SkPdfPodofoMapper_autogen.h"
+
+#ifndef SkPdfParser_DEFINED
+#define SkPdfParser_DEFINED
+
+
+enum SkPdfTokenType {
+    kKeyword_TokenType,
+    kObject_TokenType,
+    kImageData_TokenType,  // TODO(edisonn): inline images seem to work without it
+};
+
+struct PdfToken {
+    const char*      fKeyword;
+    SkPdfObject*     fObject;
+    SkPdfTokenType   fType;
+
+    PdfToken() : fKeyword(NULL), fObject(NULL) {}
+};
+
+class SkPdfTokenizer {
+    PdfContentsTokenizer* fTokenizer;
+    PdfMemDocument* fDoc;
+
+    char* fUncompressedStream;
+    pdf_long fUncompressedStreamLength;
+
+    bool fEmpty;
+    bool fHasPutBack;
+    PdfToken fPutBack;
+
+public:
+    SkPdfTokenizer(PdfMemDocument* doc = NULL, PdfContentsTokenizer* tokenizer = NULL) : fDoc(doc), fTokenizer(tokenizer), fEmpty(false), fUncompressedStream(NULL), fUncompressedStreamLength(0), fHasPutBack(false) {}
+    SkPdfTokenizer(const SkPdfObject* objWithStream) : fDoc(NULL), fTokenizer(NULL), fHasPutBack(false), fEmpty(false) {
+        fUncompressedStream = NULL;
+        fUncompressedStreamLength = 0;
+
+        fDoc = NULL;
+
+
+        try {
+            objWithStream->podofo()->GetStream()->GetFilteredCopy(&fUncompressedStream, &fUncompressedStreamLength);
+            if (fUncompressedStream != NULL && fUncompressedStreamLength != 0) {
+                fTokenizer = new PdfContentsTokenizer(fUncompressedStream, fUncompressedStreamLength);
+            } else {
+                fEmpty = true;
+            }
+        } catch (PdfError& e) {
+            fEmpty = true;
+        }
+
+    }
+
+    SkPdfTokenizer(const char* buffer, int len) : fDoc(NULL), fTokenizer(NULL), fHasPutBack(false), fUncompressedStream(NULL), fUncompressedStreamLength(0), fEmpty(false) {
+        try {
+            fTokenizer = new PdfContentsTokenizer(buffer, len);
+        } catch (PdfError& e) {
+            fEmpty = true;
+        }
+    }
+
+    ~SkPdfTokenizer() {
+        free(fUncompressedStream);
+    }
+
+    void PutBack(PdfToken token) {
+        SkASSERT(!fHasPutBack);
+        fHasPutBack = true;
+        fPutBack = token;
+    }
+
+    bool readToken(PdfToken* token) {
+        if (fHasPutBack) {
+            *token = fPutBack;
+            fHasPutBack = false;
+            return true;
+        }
+
+        if (fEmpty) {
+            return false;
+        }
+
+        PdfVariant var;
+        EPdfContentsType type;
+
+        token->fKeyword = NULL;
+        token->fObject = NULL;
+
+        bool ret = fTokenizer->ReadNext(type, token->fKeyword, var);
+
+        if (!ret) return ret;
+
+        switch (type) {
+            case ePdfContentsType_Keyword:
+                token->fType = kKeyword_TokenType;
+                break;
+
+            case ePdfContentsType_Variant: {
+                    token->fType = kObject_TokenType;
+                    PdfObject* obj = new PdfObject(var);
+                    PodofoMapper::map(*fDoc, *obj, &token->fObject);
+                }
+                break;
+
+            case ePdfContentsType_ImageData:
+                token->fType = kImageData_TokenType;
+                // TODO(edisonn): inline images seem to work without it
+                break;
+        }
+#ifdef PDF_TRACE
+        std::string str;
+        if (token->fObject) {
+            token->fObject->podofo()->ToString(str);
+        }
+        printf("%s %s\n", token->fType == kKeyword_TokenType ? "Keyword" : token->fType == kObject_TokenType ? "Object" : "ImageData", token->fKeyword ? token->fKeyword : str.c_str());
+#endif
+        return ret;
+    }
+};
+
+class SkPdfDoc {
+    PdfMemDocument fDoc;
+public:
+
+    PdfMemDocument& podofo() {return fDoc;}
+
+    SkPdfDoc(const char* path) : fDoc(path) {}
+
+    int pages() {
+        return fDoc.GetPageCount();
+    }
+
+    // Can return NULL
+    SkPdfPageObjectDictionary* page(int n) {
+        SkPdfPageObjectDictionary* page = NULL;
+        PodofoMapper::map(fDoc, *fDoc.GetPage(n)->GetObject(), &page);
+        return page;
+    }
+
+    SkRect MediaBox(int n) {
+        PdfRect rect = fDoc.GetPage(n)->GetMediaBox();
+        SkRect skrect = SkRect::MakeLTRB(SkDoubleToScalar(rect.GetLeft()),
+                                         SkDoubleToScalar(rect.GetBottom()),
+                                         SkDoubleToScalar(rect.GetLeft() + rect.GetWidth()),
+                                         SkDoubleToScalar(rect.GetBottom() + rect.GetHeight()));
+        return skrect;
+    }
+
+    SkPdfTokenizer* tokenizerOfPage(int n) {
+        PdfContentsTokenizer* t = new PdfContentsTokenizer(fDoc.GetPage(n));
+        return new SkPdfTokenizer(&fDoc, t);
+    }
+};
+
+#endif  // SkPdfParser_DEFINED