Implement FPDFAction_GetFilePath().

fpdfsdk/src/fpdfdoc.cpp

Index: fpdfsdk/src/fpdfdoc.cpp
diff --git a/fpdfsdk/src/fpdfdoc.cpp b/fpdfsdk/src/fpdfdoc.cpp
index 5d2469c160759f4a6521e8bdb96c0b138affd31d..6a1991d4e1c816c4f87851e8ec15a72417169b16 100644
--- a/fpdfsdk/src/fpdfdoc.cpp
+++ b/fpdfsdk/src/fpdfdoc.cpp
@@ -126,7 +126,8 @@ DLLEXPORT FPDF_ACTION STDCALL FPDFBookmark_GetAction(FPDF_BOOKMARK pDict) {
 
 DLLEXPORT unsigned long STDCALL FPDFAction_GetType(FPDF_ACTION pDict) {
   if (!pDict)
-    return 0;
+    return PDFACTION_UNSUPPORTED;
+
   CPDF_Action action((CPDF_Dictionary*)pDict);
   CPDF_Action::ActionType type = action.GetType();
   switch (type) {
@@ -141,7 +142,6 @@ DLLEXPORT unsigned long STDCALL FPDFAction_GetType(FPDF_ACTION pDict) {
     default:
       return PDFACTION_UNSUPPORTED;
   }
-  return PDFACTION_UNSUPPORTED;
 }
 
 DLLEXPORT FPDF_DEST STDCALL FPDFAction_GetDest(FPDF_DOCUMENT document,
@@ -155,6 +155,20 @@ DLLEXPORT FPDF_DEST STDCALL FPDFAction_GetDest(FPDF_DOCUMENT document,
   return action.GetDest(pDoc).GetObject();
 }
 
+DLLEXPORT unsigned long STDCALL
+FPDFAction_GetFilePath(FPDF_ACTION pDict, void* buffer, unsigned long buflen) {
+  unsigned long type = FPDFAction_GetType(pDict);
+  if (type != PDFACTION_REMOTEGOTO && type != PDFACTION_LAUNCH)
+    return 0;
+
+  CPDF_Action action((CPDF_Dictionary*)pDict);
+  CFX_ByteString path = action.GetFilePath().UTF8Encode();
+  unsigned long len = path.GetLength() + 1;
+  if (buffer && buflen >= len)

[jun_fang, 2015/09/14 12:10:43]

it should return 0 in 'else' rather than len.

[Lei Zhang, 2015/09/15 08:24:50]

Are you saying I should write the following?

if (buffer && buflen >= len) {
  FXSYS_memcpy(buffer, path.c_str(), len);
  return len;
}
return 0;  // (else case)
  

[jun_fang, 2015/09/15 08:35:03]

yes. For else cases, when buffer is null or buflen is less than len,
the memory that buffer points to is invalid for callers. We need
to inform the callers by the returned value (0). 

[Lei Zhang, 2015/09/15 08:50:57]

But returning 0 contradicts the comments section of the documentation for this
function in the header file. Same for FPDFAction_GetURIPath() below. It's ok to
call FPDFAction_GetFilePath(action, nullptr, 0) and get back a non-zero value,
because that value is then used to allocate memory for a second
FPDFAction_GetFilePath(action, buf, previous_retval) call.

+    FXSYS_memcpy(buffer, path.c_str(), len);
+  return len;
+}
+
 DLLEXPORT unsigned long STDCALL FPDFAction_GetURIPath(FPDF_DOCUMENT document,
                                                       FPDF_ACTION pDict,
                                                       void* buffer,