Add a NULL check in pdf_page_colors.cpp
[pdfium.git] / public / fpdf_progressive.h
1 // Copyright 2014 PDFium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
6
7 #ifndef PUBLIC_FPDF_PROGRESSIVE_H_
8 #define PUBLIC_FPDF_PROGRESSIVE_H_
9
10 #include "fpdfview.h"
11
12 // Flags for progressive process status.
13 #define FPDF_RENDER_READER 0
14 #define FPDF_RENDER_TOBECOUNTINUED 1
15 #define FPDF_RENDER_DONE 2
16 #define FPDF_RENDER_FAILED 3
17
18 #ifdef __cplusplus
19 extern "C" {
20 #endif
21
22 // IFPDF_RENDERINFO interface.
23 typedef struct _IFSDK_PAUSE {
24   /**
25   * Version number of the interface. Currently must be 1.
26   **/
27   int version;
28
29   /*
30   * Method: NeedToPauseNow
31   *           Check if we need to pause a progressive process now.
32   * Interface Version:
33   *           1
34   * Implementation Required:
35   *           yes
36   * Parameters:
37   *           pThis       -   Pointer to the interface structure itself
38   * Return Value:
39   *            Non-zero for pause now, 0 for continue.
40   *
41   */
42   FPDF_BOOL (*NeedToPauseNow)(struct _IFSDK_PAUSE* pThis);
43
44   // A user defined data pointer, used by user's application. Can be NULL.
45   void* user;
46 } IFSDK_PAUSE;
47
48 // Function: FPDF_RenderPageBitmap_Start
49 //          Start to render page contents to a device independent bitmap
50 //          progressively.
51 // Parameters:
52 //          bitmap      -   Handle to the device independent bitmap (as the
53 //          output buffer).
54 //                          Bitmap handle can be created by FPDFBitmap_Create
55 //                          function.
56 //          page        -   Handle to the page. Returned by FPDF_LoadPage
57 //          function.
58 //          start_x     -   Left pixel position of the display area in the
59 //          bitmap coordinate.
60 //          start_y     -   Top pixel position of the display area in the bitmap
61 //          coordinate.
62 //          size_x      -   Horizontal size (in pixels) for displaying the page.
63 //          size_y      -   Vertical size (in pixels) for displaying the page.
64 //          rotate      -   Page orientation: 0 (normal), 1 (rotated 90 degrees
65 //          clockwise),
66 //                              2 (rotated 180 degrees), 3 (rotated 90 degrees
67 //                              counter-clockwise).
68 //          flags       -   0 for normal display, or combination of flags
69 //          defined above.
70 //          pause       -   The IFSDK_PAUSE interface.A callback mechanism
71 //          allowing the page rendering process
72 // Return value:
73 //          Rendering Status. See flags for progressive process status for the
74 //          details.
75 //
76 DLLEXPORT int STDCALL FPDF_RenderPageBitmap_Start(FPDF_BITMAP bitmap,
77                                                   FPDF_PAGE page,
78                                                   int start_x,
79                                                   int start_y,
80                                                   int size_x,
81                                                   int size_y,
82                                                   int rotate,
83                                                   int flags,
84                                                   IFSDK_PAUSE* pause);
85
86 // Function: FPDF_RenderPage_Continue
87 //          Continue rendering a PDF page.
88 // Parameters:
89 //          page        -   Handle to the page. Returned by FPDF_LoadPage
90 //          function.
91 //          pause       -   The IFSDK_PAUSE interface.A callback mechanism
92 //          allowing the page rendering process
93 //                          to be paused before it's finished. This can be NULL
94 //                          if you don't want to pause.
95 // Return value:
96 //          The rendering status. See flags for progressive process status for
97 //          the details.
98 DLLEXPORT int STDCALL FPDF_RenderPage_Continue(FPDF_PAGE page,
99                                                IFSDK_PAUSE* pause);
100
101 // Function: FPDF_RenderPage_Close
102 //          Release the resource allocate during page rendering. Need to be
103 //          called after finishing rendering or
104 //          cancel the rendering.
105 // Parameters:
106 //          page        -   Handle to the page. Returned by FPDF_LoadPage
107 //          function.
108 // Return value:
109 //          NULL
110 DLLEXPORT void STDCALL FPDF_RenderPage_Close(FPDF_PAGE page);
111
112 #ifdef __cplusplus
113 }
114 #endif
115
116 #endif  // PUBLIC_FPDF_PROGRESSIVE_H_