Add a build target and a proper export header for shared library builds.

This CL adds support for Chromium's component build feature to pdfium.

The export header stub in fpdfview.h is expanded to match Chromium's
export mechanisms and patterns (fixes pdfium:825).

A component/shared library build can be triggered by adding

is_component_build = true

as a gn argument. Please note that setting this will also affect some
of pdfiums dependencies like v8, which will be build as components
too.

Additionally, this CL provides a "pdf_source_set" template which
dynamically enables the use of "source_set" when building a complete
static library or a shared library to reduce build time.

When testing this it is recommended to only build the pdfium target as
most of pdfiums test rely on non-public functions which aren't exported
by the shared library.

Bug: pdfium:825,pdfium:826
Change-Id: Icedc538ec535e11d1e53c4d5fabc8c064b275752
Reviewed-on: https://pdfium-review.googlesource.com/8970
Reviewed-by: dsinclair <dsinclair@chromium.org>
Commit-Queue: dsinclair <dsinclair@chromium.org>

1 files changed, 21 insertions, 19 deletions

diff --git a/fpdfsdk/fpdfeditimg.cpp b/fpdfsdk/fpdfeditimg.cpp
index b4254e97c6..f19e21c8ff 100644
--- a/fpdfsdk/fpdfeditimg.cpp
+++ b/fpdfsdk/fpdfeditimg.cpp
@@ -47,7 +47,7 @@ bool LoadJpegHelper(FPDF_PAGE* pages,
 
 }  // namespace
 
-DLLEXPORT FPDF_PAGEOBJECT STDCALL
+FPDF_EXPORT FPDF_PAGEOBJECT FPDF_CALLCONV
 FPDFPageObj_NewImageObj(FPDF_DOCUMENT document) {
   CPDF_Document* pDoc = CPDFDocumentFromFPDFDocument(document);
   if (!pDoc)
@@ -58,7 +58,7 @@ FPDFPageObj_NewImageObj(FPDF_DOCUMENT document) {
   return pImageObj.release();
 }
 
-DLLEXPORT FPDF_BOOL STDCALL
+FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV
 FPDFImageObj_LoadJpegFile(FPDF_PAGE* pages,
                           int nCount,
                           FPDF_PAGEOBJECT image_object,
@@ -66,7 +66,7 @@ FPDFImageObj_LoadJpegFile(FPDF_PAGE* pages,
   return LoadJpegHelper(pages, nCount, image_object, fileAccess, false);
 }
 
-DLLEXPORT FPDF_BOOL STDCALL
+FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV
 FPDFImageObj_LoadJpegFileInline(FPDF_PAGE* pages,
                                 int nCount,
                                 FPDF_PAGEOBJECT image_object,
@@ -74,13 +74,14 @@ FPDFImageObj_LoadJpegFileInline(FPDF_PAGE* pages,
   return LoadJpegHelper(pages, nCount, image_object, fileAccess, true);
 }
 
-DLLEXPORT FPDF_BOOL STDCALL FPDFImageObj_SetMatrix(FPDF_PAGEOBJECT image_object,
-                                                   double a,
-                                                   double b,
-                                                   double c,
-                                                   double d,
-                                                   double e,
-                                                   double f) {
+FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV
+FPDFImageObj_SetMatrix(FPDF_PAGEOBJECT image_object,
+                       double a,
+                       double b,
+                       double c,
+                       double d,
+                       double e,
+                       double f) {
   if (!image_object)
     return false;
 
@@ -93,10 +94,11 @@ DLLEXPORT FPDF_BOOL STDCALL FPDFImageObj_SetMatrix(FPDF_PAGEOBJECT image_object,
   return true;
 }
 
-DLLEXPORT FPDF_BOOL STDCALL FPDFImageObj_SetBitmap(FPDF_PAGE* pages,
-                                                   int nCount,
-                                                   FPDF_PAGEOBJECT image_object,
-                                                   FPDF_BITMAP bitmap) {
+FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV
+FPDFImageObj_SetBitmap(FPDF_PAGE* pages,
+                       int nCount,
+                       FPDF_PAGEOBJECT image_object,
+                       FPDF_BITMAP bitmap) {
   if (!image_object || !bitmap || !pages)
     return false;
 
@@ -113,7 +115,7 @@ DLLEXPORT FPDF_BOOL STDCALL FPDFImageObj_SetBitmap(FPDF_PAGE* pages,
   return true;
 }
 
-DLLEXPORT FPDF_BITMAP STDCALL
+FPDF_EXPORT FPDF_BITMAP FPDF_CALLCONV
 FPDFImageObj_GetBitmap(FPDF_PAGEOBJECT image_object) {
   CPDF_PageObject* pObj = CPDFPageObjectFromFPDFPageObject(image_object);
   if (!pObj || !pObj->IsImage())
@@ -140,7 +142,7 @@ FPDFImageObj_GetBitmap(FPDF_PAGEOBJECT image_object) {
   return pBitmap.Leak();
 }
 
-DLLEXPORT unsigned long STDCALL
+FPDF_EXPORT unsigned long FPDF_CALLCONV
 FPDFImageObj_GetImageDataDecoded(FPDF_PAGEOBJECT image_object,
                                  void* buffer,
                                  unsigned long buflen) {
@@ -159,7 +161,7 @@ FPDFImageObj_GetImageDataDecoded(FPDF_PAGEOBJECT image_object,
   return DecodeStreamMaybeCopyAndReturnLength(pImgStream, buffer, buflen);
 }
 
-DLLEXPORT unsigned long STDCALL
+FPDF_EXPORT unsigned long FPDF_CALLCONV
 FPDFImageObj_GetImageDataRaw(FPDF_PAGEOBJECT image_object,
                              void* buffer,
                              unsigned long buflen) {
@@ -182,7 +184,7 @@ FPDFImageObj_GetImageDataRaw(FPDF_PAGEOBJECT image_object,
   return len;
 }
 
-DLLEXPORT int STDCALL
+FPDF_EXPORT int FPDF_CALLCONV
 FPDFImageObj_GetImageFilterCount(FPDF_PAGEOBJECT image_object) {
   CPDF_PageObject* pObj = CPDFPageObjectFromFPDFPageObject(image_object);
   if (!pObj || !pObj->IsImage())
@@ -205,7 +207,7 @@ FPDFImageObj_GetImageFilterCount(FPDF_PAGEOBJECT image_object) {
   return 0;
 }
 
-DLLEXPORT unsigned long STDCALL
+FPDF_EXPORT unsigned long FPDF_CALLCONV
 FPDFImageObj_GetImageFilter(FPDF_PAGEOBJECT image_object,
                             int index,
                             void* buffer,