For DiffChecker PDFium Build

So this is basically us 'stealing' an entire open source project just to build PDFium for DiffChecker.

To build, just navigate to the packages/pdfium directory and run make build. The pdfium.js and .wasm files will be in docker/dist.

Other Info:

Compared to the repo we forked off of, this repo also includes the methods and functions we want to export in the txt files (which were previously hidden by .gitignore).

Runtime methods

Taken directly from our fork of pdfium-lib; the old build process, in the wasm.py file.

Functions

This is more complicated to find, but in pdfium-lib, the Python build script would read from an XML file and put essentially all the tags that contain functions names as exported functions. I'm 100% sure there are much better ways of getting this list of functions.

• We filtered it down slightly to the relevant functions for our uses. Most likely doesn't save much space if at all; I believe it only affects the .js export size.
• Refer to Diffchecker repo's PR history for scripts to parse our code for this information.
• That basically just means you'll have to figure out yourself what functions to export for the build. The easiest method is to just include everything in the list below.

To add a function to the build, add the name to the exported-functions.txt file.

The full list of these functions from searching the XML

Text='FPDFAnnot_IsSupportedSubtype'
Text='FPDFPage_CreateAnnot'
Text='FPDFPage_GetAnnotCount'
Text='FPDFPage_GetAnnot'
Text='FPDFPage_GetAnnotIndex'
Text='FPDFPage_CloseAnnot'
Text='FPDFPage_RemoveAnnot'
Text='FPDFAnnot_GetSubtype'
Text='FPDFAnnot_IsObjectSupportedSubtype'
Text='FPDFAnnot_UpdateObject'
Text='FPDFAnnot_AddInkStroke'
Text='FPDFAnnot_RemoveInkList'
Text='FPDFAnnot_AppendObject'
Text='FPDFAnnot_GetObjectCount'
Text='FPDFAnnot_GetObject'
Text='FPDFAnnot_RemoveObject'
Text='FPDFAnnot_SetColor'
Text='FPDFAnnot_GetColor'
Text='FPDFAnnot_HasAttachmentPoints'
Text='FPDFAnnot_SetAttachmentPoints'
Text='FPDFAnnot_AppendAttachmentPoints'
Text='FPDFAnnot_CountAttachmentPoints'
Text='FPDFAnnot_GetAttachmentPoints'
Text='FPDFAnnot_SetRect'
Text='FPDFAnnot_GetRect'
Text='FPDFAnnot_GetVertices'
Text='FPDFAnnot_GetInkListCount'
Text='FPDFAnnot_GetInkListPath'
Text='FPDFAnnot_GetLine'
Text='FPDFAnnot_SetBorder'
Text='FPDFAnnot_GetBorder'
Text='FPDFAnnot_GetFormAdditionalActionJavaScript'
Text='FPDFAnnot_HasKey'
Text='FPDFAnnot_GetValueType'
Text='FPDFAnnot_SetStringValue'
Text='FPDFAnnot_GetStringValue'
Text='FPDFAnnot_GetNumberValue'
Text='FPDFAnnot_SetAP'
Text='FPDFAnnot_GetAP'
Text='FPDFAnnot_GetLinkedAnnot'
Text='FPDFAnnot_GetFlags'
Text='FPDFAnnot_SetFlags'
Text='FPDFAnnot_GetFormFieldFlags'
Text='FPDFAnnot_GetFormFieldAtPoint'
Text='FPDFAnnot_GetFormFieldName'
Text='FPDFAnnot_GetFormFieldAlternateName'
Text='FPDFAnnot_GetFormFieldType'
Text='FPDFAnnot_GetFormFieldValue'
Text='FPDFAnnot_GetOptionCount'
Text='FPDFAnnot_GetOptionLabel'
Text='FPDFAnnot_IsOptionSelected'
Text='FPDFAnnot_GetFontSize'
Text='FPDFAnnot_GetFontColor'
Text='FPDFAnnot_IsChecked'
Text='FPDFAnnot_SetFocusableSubtypes'
Text='FPDFAnnot_GetFocusableSubtypesCount'
Text='FPDFAnnot_GetFocusableSubtypes'
Text='FPDFAnnot_GetLink'
Text='FPDFAnnot_GetFormControlCount'
Text='FPDFAnnot_GetFormControlIndex'
Text='FPDFAnnot_GetFormFieldExportValue'
Text='FPDFAnnot_SetURI'
Text='FPDFAnnot_GetFileAttachment'
Text='FPDFAnnot_AddFileAttachment'
Text='FPDFDoc_GetAttachmentCount'
Text='FPDFDoc_AddAttachment'
Text='FPDFDoc_GetAttachment'
Text='FPDFDoc_DeleteAttachment'
Text='FPDFAttachment_GetName'
Text='FPDFAttachment_HasKey'
Text='FPDFAttachment_GetValueType'
Text='FPDFAttachment_SetStringValue'
Text='FPDFAttachment_GetStringValue'
Text='FPDFAttachment_SetFile'
Text='FPDFAttachment_GetFile'
Text='FPDFCatalog_IsTagged'
Text='FPDFCatalog_SetLanguage'
Text='FPDFAvail_Create'
Text='FPDFAvail_Destroy'
Text='FPDFAvail_IsDocAvail'
Text='FPDFAvail_GetDocument'
Text='FPDFAvail_GetFirstPageNum'
Text='FPDFAvail_IsPageAvail'
Text='FPDFAvail_IsFormAvail'
Text='FPDFAvail_IsLinearized'
Text='FPDFBookmark_GetFirstChild'
Text='FPDFBookmark_GetNextSibling'
Text='FPDFBookmark_GetTitle'
Text='FPDFBookmark_GetCount'
Text='FPDFBookmark_Find'
Text='FPDFBookmark_GetDest'
Text='FPDFBookmark_GetAction'
Text='FPDFAction_GetType'
Text='FPDFAction_GetDest'
Text='FPDFAction_GetFilePath'
Text='FPDFAction_GetURIPath'
Text='FPDFDest_GetDestPageIndex'
Text='FPDFDest_GetView'
Text='FPDFDest_GetLocationInPage'
Text='FPDFLink_GetLinkAtPoint'
Text='FPDFLink_GetLinkZOrderAtPoint'
Text='FPDFLink_GetDest'
Text='FPDFLink_GetAction'
Text='FPDFLink_Enumerate'
Text='FPDFLink_GetAnnot'
Text='FPDFLink_GetAnnotRect'
Text='FPDFLink_CountQuadPoints'
Text='FPDFLink_GetQuadPoints'
Text='FPDF_GetPageAAction'
Text='FPDF_GetFileIdentifier'
Text='FPDF_GetMetaText'
Text='FPDF_GetPageLabel'
Text='FPDF_CreateNewDocument'
Text='FPDFPage_New'
Text='FPDFPage_Delete'
Text='FPDF_MovePages'
Text='FPDFPage_GetRotation'
Text='FPDFPage_SetRotation'
Text='FPDFPage_InsertObject'
Text='FPDFPage_RemoveObject'
Text='FPDFPage_CountObjects'
Text='FPDFPage_GetObject'
Text='FPDFPage_HasTransparency'
Text='FPDFPage_GenerateContent'
Text='FPDFPageObj_Destroy'
Text='FPDFPageObj_HasTransparency'
Text='FPDFPageObj_GetType'
Text='FPDFPageObj_GetIsActive'
Text='FPDFPageObj_SetIsActive'
Text='FPDFPageObj_Transform'
Text='FPDFPageObj_TransformF'
Text='FPDFPageObj_GetMatrix'
Text='FPDFPageObj_SetMatrix'
Text='FPDFPage_TransformAnnots'
Text='FPDFPageObj_NewImageObj'
Text='FPDFPageObj_GetMarkedContentID'
Text='FPDFPageObj_CountMarks'
Text='FPDFPageObj_GetMark'
Text='FPDFPageObj_AddMark'
Text='FPDFPageObj_RemoveMark'
Text='FPDFPageObjMark_GetName'
Text='FPDFPageObjMark_CountParams'
Text='FPDFPageObjMark_GetParamKey'
Text='FPDFPageObjMark_GetParamValueType'
Text='FPDFPageObjMark_GetParamIntValue'
Text='FPDFPageObjMark_GetParamStringValue'
Text='FPDFPageObjMark_GetParamBlobValue'
Text='FPDFPageObjMark_SetIntParam'
Text='FPDFPageObjMark_SetStringParam'
Text='FPDFPageObjMark_SetBlobParam'
Text='FPDFPageObjMark_RemoveParam'
Text='FPDFImageObj_LoadJpegFile'
Text='FPDFImageObj_LoadJpegFileInline'
Text='FPDFImageObj_SetMatrix'
Text='FPDFImageObj_SetBitmap'
Text='FPDFImageObj_GetBitmap'
Text='FPDFImageObj_GetRenderedBitmap'
Text='FPDFImageObj_GetImageDataDecoded'
Text='FPDFImageObj_GetImageDataRaw'
Text='FPDFImageObj_GetImageFilterCount'
Text='FPDFImageObj_GetImageFilter'
Text='FPDFImageObj_GetImageMetadata'
Text='FPDFImageObj_GetImagePixelSize'
Text='FPDFImageObj_GetIccProfileDataDecoded'
Text='FPDFPageObj_CreateNewPath'
Text='FPDFPageObj_CreateNewRect'
Text='FPDFPageObj_GetBounds'
Text='FPDFPageObj_GetRotatedBounds'
Text='FPDFPageObj_SetBlendMode'
Text='FPDFPageObj_SetStrokeColor'
Text='FPDFPageObj_GetStrokeColor'
Text='FPDFPageObj_SetStrokeWidth'
Text='FPDFPageObj_GetStrokeWidth'
Text='FPDFPageObj_GetLineJoin'
Text='FPDFPageObj_SetLineJoin'
Text='FPDFPageObj_GetLineCap'
Text='FPDFPageObj_SetLineCap'
Text='FPDFPageObj_SetFillColor'
Text='FPDFPageObj_GetFillColor'
Text='FPDFPageObj_GetDashPhase'
Text='FPDFPageObj_SetDashPhase'
Text='FPDFPageObj_GetDashCount'
Text='FPDFPageObj_GetDashArray'
Text='FPDFPageObj_SetDashArray'
Text='FPDFPath_CountSegments'
Text='FPDFPath_GetPathSegment'
Text='FPDFPathSegment_GetPoint'
Text='FPDFPathSegment_GetType'
Text='FPDFPathSegment_GetClose'
Text='FPDFPath_MoveTo'
Text='FPDFPath_LineTo'
Text='FPDFPath_BezierTo'
Text='FPDFPath_Close'
Text='FPDFPath_SetDrawMode'
Text='FPDFPath_GetDrawMode'
Text='FPDFPageObj_NewTextObj'
Text='FPDFText_SetText'
Text='FPDFText_SetCharcodes'
Text='FPDFText_LoadFont'
Text='FPDFText_LoadStandardFont'
Text='FPDFText_LoadCidType2Font'
Text='FPDFTextObj_GetFontSize'
Text='FPDFFont_Close'
Text='FPDFPageObj_CreateTextObj'
Text='FPDFTextObj_GetTextRenderMode'
Text='FPDFTextObj_SetTextRenderMode'
Text='FPDFTextObj_GetText'
Text='FPDFTextObj_GetRenderedBitmap'
Text='FPDFTextObj_GetFont'
Text='FPDFFont_GetBaseFontName'
Text='FPDFFont_GetFamilyName'
Text='FPDFFont_GetFontData'
Text='FPDFFont_GetIsEmbedded'
Text='FPDFFont_GetFlags'
Text='FPDFFont_GetWeight'
Text='FPDFFont_GetItalicAngle'
Text='FPDFFont_GetAscent'
Text='FPDFFont_GetDescent'
Text='FPDFFont_GetGlyphWidth'
Text='FPDFFont_GetGlyphPath'
Text='FPDFGlyphPath_CountGlyphSegments'
Text='FPDFGlyphPath_GetGlyphPathSegment'
Text='FPDFFormObj_CountObjects'
Text='FPDFFormObj_GetObject'
Text='FSDK_SetUnSpObjProcessHandler'
Text='FSDK_SetTimeFunction'
Text='FSDK_SetLocaltimeFunction'
Text='FPDFDoc_GetPageMode'
Text='FPDFPage_Flatten'
Text='FPDFDOC_InitFormFillEnvironment'
Text='FPDFDOC_ExitFormFillEnvironment'
Text='FORM_OnAfterLoadPage'
Text='FORM_OnBeforeClosePage'
Text='FORM_DoDocumentJSAction'
Text='FORM_DoDocumentOpenAction'
Text='FORM_DoDocumentAAction'
Text='FORM_DoPageAAction'
Text='FORM_OnMouseMove'
Text='FORM_OnMouseWheel'
Text='FORM_OnFocus'
Text='FORM_OnLButtonDown'
Text='FORM_OnRButtonDown'
Text='FORM_OnLButtonUp'
Text='FORM_OnRButtonUp'
Text='FORM_OnLButtonDoubleClick'
Text='FORM_OnKeyDown'
Text='FORM_OnKeyUp'
Text='FORM_OnChar'
Text='FORM_GetFocusedText'
Text='FORM_GetSelectedText'
Text='FORM_ReplaceAndKeepSelection'
Text='FORM_ReplaceSelection'
Text='FORM_SelectAllText'
Text='FORM_CanUndo'
Text='FORM_CanRedo'
Text='FORM_Undo'
Text='FORM_Redo'
Text='FORM_ForceToKillFocus'
Text='FORM_GetFocusedAnnot'
Text='FORM_SetFocusedAnnot'
Text='FPDFPage_HasFormFieldAtPoint'
Text='FPDFPage_FormFieldZOrderAtPoint'
Text='FPDF_SetFormFieldHighlightColor'
Text='FPDF_SetFormFieldHighlightAlpha'
Text='FPDF_RemoveFormFieldHighlight'
Text='FPDF_FFLDraw'
Text='FPDF_GetFormType'
Text='FORM_SetIndexSelected'
Text='FORM_IsIndexSelected'
Text='FPDF_LoadXFA'
Text='FPDFDoc_GetJavaScriptActionCount'
Text='FPDFDoc_GetJavaScriptAction'
Text='FPDFDoc_CloseJavaScriptAction'
Text='FPDFJavaScriptAction_GetName'
Text='FPDFJavaScriptAction_GetScript'
Text='FPDF_ImportPagesByIndex'
Text='FPDF_ImportPages'
Text='FPDF_ImportNPagesToOne'
Text='FPDF_NewXObjectFromPage'
Text='FPDF_CloseXObject'
Text='FPDF_NewFormObjectFromXObject'
Text='FPDF_CopyViewerPreferences'
Text='FPDF_RenderPageBitmapWithColorScheme_Start'
Text='FPDF_RenderPageBitmap_Start'
Text='FPDF_RenderPage_Continue'
Text='FPDF_RenderPage_Close'
Text='FPDF_SaveAsCopy'
Text='FPDF_SaveWithVersion'
Text='FPDFText_GetCharIndexFromTextIndex'
Text='FPDFText_GetTextIndexFromCharIndex'
Text='FPDF_GetSignatureCount'
Text='FPDF_GetSignatureObject'
Text='FPDFSignatureObj_GetContents'
Text='FPDFSignatureObj_GetByteRange'
Text='FPDFSignatureObj_GetSubFilter'
Text='FPDFSignatureObj_GetReason'
Text='FPDFSignatureObj_GetTime'
Text='FPDFSignatureObj_GetDocMDPPermission'
Text='FPDF_StructTree_GetForPage'
Text='FPDF_StructTree_Close'
Text='FPDF_StructTree_CountChildren'
Text='FPDF_StructTree_GetChildAtIndex'
Text='FPDF_StructElement_GetAltText'
Text='FPDF_StructElement_GetActualText'
Text='FPDF_StructElement_GetID'
Text='FPDF_StructElement_GetLang'
Text='FPDF_StructElement_GetStringAttribute'
Text='FPDF_StructElement_GetMarkedContentID'
Text='FPDF_StructElement_GetType'
Text='FPDF_StructElement_GetObjType'
Text='FPDF_StructElement_GetTitle'
Text='FPDF_StructElement_CountChildren'
Text='FPDF_StructElement_GetChildAtIndex'
Text='FPDF_StructElement_GetChildMarkedContentID'
Text='FPDF_StructElement_GetParent'
Text='FPDF_StructElement_GetAttributeCount'
Text='FPDF_StructElement_GetAttributeAtIndex'
Text='FPDF_StructElement_Attr_GetCount'
Text='FPDF_StructElement_Attr_GetName'
Text='FPDF_StructElement_Attr_GetValue'
Text='FPDF_StructElement_Attr_GetType'
Text='FPDF_StructElement_Attr_GetBooleanValue'
Text='FPDF_StructElement_Attr_GetNumberValue'
Text='FPDF_StructElement_Attr_GetStringValue'
Text='FPDF_StructElement_Attr_GetBlobValue'
Text='FPDF_StructElement_Attr_CountChildren'
Text='FPDF_StructElement_Attr_GetChildAtIndex'
Text='FPDF_StructElement_GetMarkedContentIdCount'
Text='FPDF_StructElement_GetMarkedContentIdAtIndex'
Text='FPDF_GetDefaultTTFMap'
Text='FPDF_GetDefaultTTFMapCount'
Text='FPDF_GetDefaultTTFMapEntry'
Text='FPDF_AddInstalledFont'
Text='FPDF_SetSystemFontInfo'
Text='FPDF_GetDefaultSystemFontInfo'
Text='FPDF_FreeDefaultSystemFontInfo'
Text='FPDFText_LoadPage'
Text='FPDFText_ClosePage'
Text='FPDFText_CountChars'
Text='FPDFText_GetUnicode'
Text='FPDFText_GetTextObject'
Text='FPDFText_IsGenerated'
Text='FPDFText_IsHyphen'
Text='FPDFText_HasUnicodeMapError'
Text='FPDFText_GetFontSize'
Text='FPDFText_GetFontInfo'
Text='FPDFText_GetFontWeight'
Text='FPDFText_GetFillColor'
Text='FPDFText_GetStrokeColor'
Text='FPDFText_GetCharAngle'
Text='FPDFText_GetCharBox'
Text='FPDFText_GetLooseCharBox'
Text='FPDFText_GetMatrix'
Text='FPDFText_GetCharOrigin'
Text='FPDFText_GetCharIndexAtPos'
Text='FPDFText_GetText'
Text='FPDFText_CountRects'
Text='FPDFText_GetRect'
Text='FPDFText_GetBoundedText'
Text='FPDFText_FindStart'
Text='FPDFText_FindNext'
Text='FPDFText_FindPrev'
Text='FPDFText_GetSchResultIndex'
Text='FPDFText_GetSchCount'
Text='FPDFText_FindClose'
Text='FPDFLink_LoadWebLinks'
Text='FPDFLink_CountWebLinks'
Text='FPDFLink_GetURL'
Text='FPDFLink_CountRects'
Text='FPDFLink_GetRect'
Text='FPDFLink_GetTextRange'
Text='FPDFLink_CloseWebLinks'
Text='FPDFPage_GetDecodedThumbnailData'
Text='FPDFPage_GetRawThumbnailData'
Text='FPDFPage_GetThumbnailAsBitmap'
Text='FPDFPage_SetMediaBox'
Text='FPDFPage_SetCropBox'
Text='FPDFPage_SetBleedBox'
Text='FPDFPage_SetTrimBox'
Text='FPDFPage_SetArtBox'
Text='FPDFPage_GetMediaBox'
Text='FPDFPage_GetCropBox'
Text='FPDFPage_GetBleedBox'
Text='FPDFPage_GetTrimBox'
Text='FPDFPage_GetArtBox'
Text='FPDFPage_TransFormWithClip'
Text='FPDFPageObj_TransformClipPath'
Text='FPDFPageObj_GetClipPath'
Text='FPDFClipPath_CountPaths'
Text='FPDFClipPath_CountPathSegments'
Text='FPDFClipPath_GetPathSegment'
Text='FPDF_CreateClipPath'
Text='FPDF_DestroyClipPath'
Text='FPDFPage_InsertClipPath'
Text='FPDF_InitLibraryWithConfig'
Text='FPDF_InitLibrary'
Text='FPDF_DestroyLibrary'
Text='FPDF_SetSandBoxPolicy'
Text='FPDF_LoadDocument'
Text='FPDF_LoadMemDocument'
Text='FPDF_LoadMemDocument64'
Text='FPDF_LoadCustomDocument'
Text='FPDF_GetFileVersion'
Text='FPDF_GetLastError'
Text='FPDF_DocumentHasValidCrossReferenceTable'
Text='FPDF_GetTrailerEnds'
Text='FPDF_GetDocPermissions'
Text='FPDF_GetDocUserPermissions'
Text='FPDF_GetSecurityHandlerRevision'
Text='FPDF_GetPageCount'
Text='FPDF_LoadPage'
Text='FPDF_GetPageWidthF'
Text='FPDF_GetPageWidth'
Text='FPDF_GetPageHeightF'
Text='FPDF_GetPageHeight'
Text='FPDF_GetPageBoundingBox'
Text='FPDF_GetPageSizeByIndexF'
Text='FPDF_GetPageSizeByIndex'
Text='FPDF_RenderPageBitmap'
Text='FPDF_RenderPageBitmapWithMatrix'
Text='FPDF_ClosePage'
Text='FPDF_CloseDocument'
Text='FPDF_DeviceToPage'
Text='FPDF_PageToDevice'
Text='FPDFBitmap_Create'
Text='FPDFBitmap_CreateEx'
Text='FPDFBitmap_GetFormat'
Text='FPDFBitmap_FillRect'
Text='FPDFBitmap_GetBuffer'
Text='FPDFBitmap_GetWidth'
Text='FPDFBitmap_GetHeight'
Text='FPDFBitmap_GetStride'
Text='FPDFBitmap_Destroy'
Text='FPDF_VIEWERREF_GetPrintScaling'
Text='FPDF_VIEWERREF_GetNumCopies'
Text='FPDF_VIEWERREF_GetPrintPageRange'
Text='FPDF_VIEWERREF_GetPrintPageRangeCount'
Text='FPDF_VIEWERREF_GetPrintPageRangeElement'
Text='FPDF_VIEWERREF_GetDuplex'
Text='FPDF_VIEWERREF_GetName'
Text='FPDF_CountNamedDests'
Text='FPDF_GetNamedDestByName'
Text='FPDF_GetNamedDest'
Text='FPDF_GetXFAPacketCount'
Text='FPDF_GetXFAPacketName'
Text='FPDF_GetXFAPacketContent'

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