Add new public APIs to find the z-order for links and widgets.

fpdfsdk/src/fpdfdoc.cpp

 // 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
 
 #include "../include/fsdk_define.h"
 #include "../../public/fpdf_doc.h"
 
 static int THISMODULE = 0;
@@ skipping 151 matching lines @@
 }
 
 static void ReleaseLinkList(void* data) {
   delete (CPDF_LinkList*)data;
 }
 
 DLLEXPORT FPDF_LINK STDCALL FPDFLink_GetLinkAtPoint(FPDF_PAGE page,
                                                     double x,
                                                     double y) {
   if (!page)
-    return NULL;
+    return nullptr;
+
   CPDF_Page* pPage = (CPDF_Page*)page;
   // Link list is stored with the document
   CPDF_Document* pDoc = pPage->m_pDocument;
   CPDF_LinkList* pLinkList = (CPDF_LinkList*)pDoc->GetPrivateData(&THISMODULE);
   if (!pLinkList) {
-    pLinkList = new CPDF_LinkList(pDoc);
+    pLinkList = new CPDF_LinkList;
     pDoc->SetPrivateData(&THISMODULE, pLinkList, ReleaseLinkList);
   }
-  return pLinkList->GetLinkAtPoint(pPage, (FX_FLOAT)x, (FX_FLOAT)y).GetDict();
+  return pLinkList->GetLinkAtPoint(pPage, (FX_FLOAT)x, (FX_FLOAT)y, nullptr)
+      .GetDict();
+}
+
+DLLEXPORT int STDCALL FPDFLink_GetLinkZOrderAtPoint(FPDF_PAGE page,
+                                                    double x,
+                                                    double y) {
+  if (!page)
+    return -1;
+
+  CPDF_Page* pPage = (CPDF_Page*)page;
+  // Link list is stored with the document
+  CPDF_Document* pDoc = pPage->m_pDocument;
+  CPDF_LinkList* pLinkList = (CPDF_LinkList*)pDoc->GetPrivateData(&THISMODULE);

[Tom Sepez, 2015/08/07 18:14:06]

nit: Is this the only place we do "get or create"? Otherwise consolidate
duplicate code?

[Lei Zhang, 2015/08/07 23:03:41]

I consolidated.

+  if (!pLinkList) {
+    pLinkList = new CPDF_LinkList;
+    pDoc->SetPrivateData(&THISMODULE, pLinkList, ReleaseLinkList);
+  }
+  int z_order = -1;
+  pLinkList->GetLinkAtPoint(pPage, (FX_FLOAT)x, (FX_FLOAT)y, &z_order);

[Tom Sepez, 2015/08/07 18:14:06]

nit: maybe (void) to indicate result not used?

[Lei Zhang, 2015/08/07 23:03:41]

Done.

+  return z_order;
 }
 
 DLLEXPORT FPDF_DEST STDCALL FPDFLink_GetDest(FPDF_DOCUMENT document,
                                              FPDF_LINK pDict) {
   if (!document)
     return NULL;
   if (!pDict)
     return NULL;
   CPDF_Document* pDoc = (CPDF_Document*)document;
   CPDF_Link link((CPDF_Dictionary*)pDict);
@@ skipping 98 matching lines @@
     return 0;
   CFX_WideString text = pInfo->GetUnicodeText(tag);
   // Use UTF-16LE encoding
   CFX_ByteString encodedText = text.UTF16LE_Encode();
   unsigned long len = encodedText.GetLength();
   if (buffer && buflen >= len) {
     FXSYS_memcpy(buffer, encodedText.c_str(), len);
   }
   return len;
 }