// Copyright 2014 PDFium Authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com #ifndef PUBLIC_FPDF_DATAAVAIL_H_ #define PUBLIC_FPDF_DATAAVAIL_H_ #include <stddef.h> #include "fpdfview.h" #define PDF_LINEARIZATION_UNKNOWN -1 #define PDF_NOT_LINEARIZED 0 #define PDF_LINEARIZED 1 #define PDF_DATA_ERROR -1 #define PDF_DATA_NOTAVAIL 0 #define PDF_DATA_AVAIL 1 #define PDF_FORM_ERROR -1 #define PDF_FORM_NOTAVAIL 0 #define PDF_FORM_AVAIL 1 #define PDF_FORM_NOTEXIST 2 #ifdef __cplusplus extern "C" { #endif // __cplusplus // Interface for checking whether sections of the file are available. typedef struct _FX_FILEAVAIL { // Version number of the interface. Must be 1. int version; // Reports if the specified data section is currently available. A section is // available if all bytes in the section are available. // // Interface Version: 1 // Implementation Required: Yes // // pThis - pointer to the interface structure. // offset - the offset of the data section in the file. // size - the size of the data section. // // Returns true if the specified data section at |offset| of |size| // is available. FPDF_BOOL (*IsDataAvail)(struct _FX_FILEAVAIL* pThis, size_t offset, size_t size); } FX_FILEAVAIL; typedef void* FPDF_AVAIL; // Create a document availability provider. // // file_avail - pointer to file availability interface. // file - pointer to a file access interface. // // Returns a handle to the document availability provider, or NULL on error. // // |FPDFAvail_Destroy| must be called when done with the availability provider. DLLEXPORT FPDF_AVAIL STDCALL FPDFAvail_Create(FX_FILEAVAIL* file_avail, FPDF_FILEACCESS* file); // Destroy the |avail| document availability provider. // // avail - handle to document availability provider to be destroyed. DLLEXPORT void STDCALL FPDFAvail_Destroy(FPDF_AVAIL avail); // Download hints interface. Used to receive hints for further downloading. typedef struct _FX_DOWNLOADHINTS { // Version number of the interface. Must be 1. int version; // Add a section to be downloaded. // // Interface Version: 1 // Implementation Required: Yes // // pThis - pointer to the interface structure. // offset - the offset of the hint reported to be downloaded. // size - the size of the hint reported to be downloaded. // // The |offset| and |size| of the section may not be unique. Part of the // section might be already available. The download manager must deal with // overlapping sections. void (*AddSegment)(struct _FX_DOWNLOADHINTS* pThis, size_t offset, size_t size); } FX_DOWNLOADHINTS; // Checks if the document is ready for loading, if not, gets download hints. // // avail - handle to document availability provider. // hints - pointer to a download hints interface. // // Returns one of: // PDF_DATA_ERROR: A common error is returned. Data availability unknown. // PDF_DATA_NOTAVAIL: Data not yet available. // PDF_DATA_AVAIL: Data available. // // Applications should call this function whenever new data arrives, and process // all the generated download hints, if any, until the function returns // |PDF_DATA_ERROR| or |PDF_DATA_AVAIL|. // // Once all data is available, call |FPDFAvail_GetDocument| to get a document // handle. DLLEXPORT int STDCALL FPDFAvail_IsDocAvail(FPDF_AVAIL avail, FX_DOWNLOADHINTS* hints); // Get document from the availability provider. // // avail - handle to document availability provider. // password - password for decrypting the PDF file. Optional. // // Returns a handle to the document. // // When |FPDFAvail_IsDocAvail| returns TRUE, call |FPDFAvail_GetDocument| to // retrieve the document handle. DLLEXPORT FPDF_DOCUMENT STDCALL FPDFAvail_GetDocument(FPDF_AVAIL avail, FPDF_BYTESTRING password); // Get the page number for the first available page in a linearized PDF. // // doc - document handle. // // Returns the zero-based index for the first available page. // // For most linearized PDFs, the first available page will be the first page, // however, some PDFs might make another page the first available page. // For non-linearized PDFs, this function will always return zero. DLLEXPORT int STDCALL FPDFAvail_GetFirstPageNum(FPDF_DOCUMENT doc); // Check if |page_index| is ready for loading, if not, get the // |FX_DOWNLOADHINTS|. // // avail - handle to document availability provider. // page_index - index number of the page. Zero for the first page. // hints - pointer to a download hints interface. Populated if // |page_index| is not available. // // Returns one of: // PDF_DATA_ERROR: A common error is returned. Data availability unknown. // PDF_DATA_NOTAVAIL: Data not yet available. // PDF_DATA_AVAIL: Data available. // // This function can be called only after |FPDFAvail_GetDocument| is called. // Applications should call this function whenever new data arrives and process // all the generated download |hints|, if any, until this function returns // |PDF_DATA_ERROR| or |PDF_DATA_AVAIL|. Applications can then perform page // loading. DLLEXPORT int STDCALL FPDFAvail_IsPageAvail(FPDF_AVAIL avail, int page_index, FX_DOWNLOADHINTS* hints); // Check if form data is ready for initialization, if not, get the // |FX_DOWNLOADHINTS|. // // avail - handle to document availability provider. // hints - pointer to a download hints interface. Populated if form is not // ready for initialization. // // Returns one of: // PDF_FORM_ERROR: A common eror, in general incorrect parameters. // PDF_FORM_NOTAVAIL: Data not available. // PDF_FORM_AVAIL: Data available. // PDF_FORM_NOTEXIST: No form data. // // This function can be called only after |FPDFAvail_GetDocument| is called. // The application should call this function whenever new data arrives and // process all the generated download |hints|, if any, until the function // |PDF_FORM_ERROR|, |PDF_FORM_AVAIL| or |PDF_FORM_NOTEXIST|. // Applications can then perform page loading. It is recommend to call // |FPDFDOC_InitFormFillEnvironment| when |PDF_FORM_AVAIL| is returned. DLLEXPORT int STDCALL FPDFAvail_IsFormAvail(FPDF_AVAIL avail, FX_DOWNLOADHINTS* hints); // Check whether a document is a linearized PDF. // // avail - handle to document availability provider. // // Returns one of: // PDF_LINEARIZED // PDF_NOT_LINEARIZED // PDF_LINEARIZATION_UNKNOWN // // |FPDFAvail_IsLinearized| will return |PDF_LINEARIZED| or |PDF_NOT_LINEARIZED| // when we have 1k of data. If the files size less than 1k, it returns // |PDF_LINEARIZATION_UNKNOWN| as there is insufficient information to determine // if the PDF is linearlized. DLLEXPORT int STDCALL FPDFAvail_IsLinearized(FPDF_AVAIL avail); #ifdef __cplusplus } // extern "C" #endif // __cplusplus #endif // PUBLIC_FPDF_DATAAVAIL_H_