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, 20 insertions, 18 deletions

diff --git a/fpdfsdk/fpdfattachment.cpp b/fpdfsdk/fpdfattachment.cpp
index 5bdb3bd4a2..b759ae2655 100644
--- a/fpdfsdk/fpdfattachment.cpp
+++ b/fpdfsdk/fpdfattachment.cpp
@@ -45,7 +45,8 @@ CFX_ByteString GenerateMD5Base16(const void* contents,
 
 }  // namespace
 
-DLLEXPORT int STDCALL FPDFDoc_GetAttachmentCount(FPDF_DOCUMENT document) {
+FPDF_EXPORT int FPDF_CALLCONV
+FPDFDoc_GetAttachmentCount(FPDF_DOCUMENT document) {
   CPDF_Document* pDoc = CPDFDocumentFromFPDFDocument(document);
   if (!pDoc)
     return 0;
@@ -53,8 +54,8 @@ DLLEXPORT int STDCALL FPDFDoc_GetAttachmentCount(FPDF_DOCUMENT document) {
   return CPDF_NameTree(pDoc, "EmbeddedFiles").GetCount();
 }
 
-DLLEXPORT FPDF_ATTACHMENT STDCALL FPDFDoc_AddAttachment(FPDF_DOCUMENT document,
-                                                        FPDF_WIDESTRING name) {
+FPDF_EXPORT FPDF_ATTACHMENT FPDF_CALLCONV
+FPDFDoc_AddAttachment(FPDF_DOCUMENT document, FPDF_WIDESTRING name) {
   CPDF_Document* pDoc = CPDFDocumentFromFPDFDocument(document);
   CFX_WideString wsName =
       CFX_WideString::FromUTF16LE(name, CFX_WideString::WStringLength(name));
@@ -97,8 +98,8 @@ DLLEXPORT FPDF_ATTACHMENT STDCALL FPDFDoc_AddAttachment(FPDF_DOCUMENT document,
   return pFile;
 }
 
-DLLEXPORT FPDF_ATTACHMENT STDCALL FPDFDoc_GetAttachment(FPDF_DOCUMENT document,
-                                                        int index) {
+FPDF_EXPORT FPDF_ATTACHMENT FPDF_CALLCONV
+FPDFDoc_GetAttachment(FPDF_DOCUMENT document, int index) {
   CPDF_Document* pDoc = CPDFDocumentFromFPDFDocument(document);
   if (!pDoc || index < 0)
     return nullptr;
@@ -111,8 +112,8 @@ DLLEXPORT FPDF_ATTACHMENT STDCALL FPDFDoc_GetAttachment(FPDF_DOCUMENT document,
   return nameTree.LookupValueAndName(index, &csName);
 }
 
-DLLEXPORT FPDF_BOOL STDCALL FPDFDoc_DeleteAttachment(FPDF_DOCUMENT document,
-                                                     int index) {
+FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV
+FPDFDoc_DeleteAttachment(FPDF_DOCUMENT document, int index) {
   CPDF_Document* pDoc = CPDFDocumentFromFPDFDocument(document);
   if (!pDoc || index < 0)
     return false;
@@ -124,7 +125,7 @@ DLLEXPORT FPDF_BOOL STDCALL FPDFDoc_DeleteAttachment(FPDF_DOCUMENT document,
   return nameTree.DeleteValueAndName(index);
 }
 
-DLLEXPORT unsigned long STDCALL
+FPDF_EXPORT unsigned long FPDF_CALLCONV
 FPDFAttachment_GetName(FPDF_ATTACHMENT attachment,
                        void* buffer,
                        unsigned long buflen) {
@@ -136,8 +137,8 @@ FPDFAttachment_GetName(FPDF_ATTACHMENT attachment,
                                              buffer, buflen);
 }
 
-DLLEXPORT FPDF_BOOL STDCALL FPDFAttachment_HasKey(FPDF_ATTACHMENT attachment,
-                                                  FPDF_WIDESTRING key) {
+FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV
+FPDFAttachment_HasKey(FPDF_ATTACHMENT attachment, FPDF_WIDESTRING key) {
   CPDF_Object* pFile = CPDFObjectFromFPDFAttachment(attachment);
   if (!pFile)
     return 0;
@@ -149,7 +150,7 @@ DLLEXPORT FPDF_BOOL STDCALL FPDFAttachment_HasKey(FPDF_ATTACHMENT attachment,
   return pParamsDict->KeyExist(CFXByteStringFromFPDFWideString(key));
 }
 
-DLLEXPORT FPDF_OBJECT_TYPE STDCALL
+FPDF_EXPORT FPDF_OBJECT_TYPE FPDF_CALLCONV
 FPDFAttachment_GetValueType(FPDF_ATTACHMENT attachment, FPDF_WIDESTRING key) {
   if (!FPDFAttachment_HasKey(attachment, key))
     return FPDF_OBJECT_UNKNOWN;
@@ -163,7 +164,7 @@ FPDFAttachment_GetValueType(FPDF_ATTACHMENT attachment, FPDF_WIDESTRING key) {
   return pObj->GetType();
 }
 
-DLLEXPORT FPDF_BOOL STDCALL
+FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV
 FPDFAttachment_SetStringValue(FPDF_ATTACHMENT attachment,
                               FPDF_WIDESTRING key,
                               FPDF_WIDESTRING value) {
@@ -185,7 +186,7 @@ FPDFAttachment_SetStringValue(FPDF_ATTACHMENT attachment,
   return true;
 }
 
-DLLEXPORT unsigned long STDCALL
+FPDF_EXPORT unsigned long FPDF_CALLCONV
 FPDFAttachment_GetStringValue(FPDF_ATTACHMENT attachment,
                               FPDF_WIDESTRING key,
                               void* buffer,
@@ -213,10 +214,11 @@ FPDFAttachment_GetStringValue(FPDF_ATTACHMENT attachment,
   return Utf16EncodeMaybeCopyAndReturnLength(value, buffer, buflen);
 }
 
-DLLEXPORT FPDF_BOOL STDCALL FPDFAttachment_SetFile(FPDF_ATTACHMENT attachment,
-                                                   FPDF_DOCUMENT document,
-                                                   const void* contents,
-                                                   const unsigned long len) {
+FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV
+FPDFAttachment_SetFile(FPDF_ATTACHMENT attachment,
+                       FPDF_DOCUMENT document,
+                       const void* contents,
+                       const unsigned long len) {
   CPDF_Object* pFile = CPDFObjectFromFPDFAttachment(attachment);
   CPDF_Document* pDoc = CPDFDocumentFromFPDFDocument(document);
   if (!pFile || !pFile->IsDictionary() || !pDoc || len > INT_MAX)
@@ -260,7 +262,7 @@ DLLEXPORT FPDF_BOOL STDCALL FPDFAttachment_SetFile(FPDF_ATTACHMENT attachment,
   return true;
 }
 
-DLLEXPORT unsigned long STDCALL
+FPDF_EXPORT unsigned long FPDF_CALLCONV
 FPDFAttachment_GetFile(FPDF_ATTACHMENT attachment,
                        void* buffer,
                        unsigned long buflen) {