Add APIs to work with a FPDF_PAGERANGE.

After getting a FPDF_PAGERANGE from FPDF_VIEWERREF_GetPrintPageRange(),
one can now use FPDF_VIEWERREF_GetPrintPageRangeCount() to get the
number of elements in the FPDF_PAGERANGE. One can then use
FPDF_VIEWERREF_GetPrintPageRangeElement() to read the elements.

Change-Id: I33eeff9026d01991ae1424e05b67f163245a35f9
Reviewed-on: https://pdfium-review.googlesource.com/32173
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: dsinclair <dsinclair@chromium.org>

4 files changed, 50 insertions, 0 deletions

diff --git a/fpdfsdk/fpdf_view.cpp b/fpdfsdk/fpdf_view.cpp
index f5eea66125..22cb62ea6e 100644
--- a/fpdfsdk/fpdf_view.cpp
+++ b/fpdfsdk/fpdf_view.cpp
@@ -1003,6 +1003,21 @@ FPDF_VIEWERREF_GetPrintPageRange(FPDF_DOCUMENT document) {
   return FPDFPageRangeFromCPDFArray(viewRef.PrintPageRange());
 }
 
+FPDF_EXPORT size_t FPDF_CALLCONV
+FPDF_VIEWERREF_GetPrintPageRangeCount(FPDF_PAGERANGE pagerange) {
+  const CPDF_Array* pArray = CPDFArrayFromFPDFPageRange(pagerange);
+  return pArray ? pArray->GetCount() : 0;
+}
+
+FPDF_EXPORT int FPDF_CALLCONV
+FPDF_VIEWERREF_GetPrintPageRangeElement(FPDF_PAGERANGE pagerange,
+                                        size_t index) {
+  const CPDF_Array* pArray = CPDFArrayFromFPDFPageRange(pagerange);
+  if (!pArray || index >= pArray->GetCount())
+    return -1;
+  return pArray->GetIntegerAt(index);
+}
+
 FPDF_EXPORT FPDF_DUPLEXTYPE FPDF_CALLCONV
 FPDF_VIEWERREF_GetDuplex(FPDF_DOCUMENT document) {
   CPDF_Document* pDoc = CPDFDocumentFromFPDFDocument(document);
diff --git a/fpdfsdk/fpdf_view_c_api_test.c b/fpdfsdk/fpdf_view_c_api_test.c
index 792acbe439..782d35d702 100644
--- a/fpdfsdk/fpdf_view_c_api_test.c
+++ b/fpdfsdk/fpdf_view_c_api_test.c
@@ -363,6 +363,8 @@ int CheckPDFiumCApi() {
     CHK(FPDF_VIEWERREF_GetPrintScaling);
     CHK(FPDF_VIEWERREF_GetNumCopies);
     CHK(FPDF_VIEWERREF_GetPrintPageRange);
+    CHK(FPDF_VIEWERREF_GetPrintPageRangeCount);
+    CHK(FPDF_VIEWERREF_GetPrintPageRangeElement);
     CHK(FPDF_VIEWERREF_GetDuplex);
     CHK(FPDF_VIEWERREF_GetName);
     CHK(FPDF_CountNamedDests);
diff --git a/fpdfsdk/fpdf_view_embeddertest.cpp b/fpdfsdk/fpdf_view_embeddertest.cpp
index 9ba406a41c..580ba76e31 100644
--- a/fpdfsdk/fpdf_view_embeddertest.cpp
+++ b/fpdfsdk/fpdf_view_embeddertest.cpp
@@ -136,6 +136,9 @@ TEST_F(FPDFViewEmbeddertest, ViewerRefDummy) {
 
   FPDF_PAGERANGE page_range = FPDF_VIEWERREF_GetPrintPageRange(document());
   EXPECT_FALSE(page_range);
+  EXPECT_EQ(0U, FPDF_VIEWERREF_GetPrintPageRangeCount(page_range));
+  EXPECT_EQ(-1, FPDF_VIEWERREF_GetPrintPageRangeElement(page_range, 0));
+  EXPECT_EQ(-1, FPDF_VIEWERREF_GetPrintPageRangeElement(page_range, 1));
 }
 
 TEST_F(FPDFViewEmbeddertest, ViewerRef) {
@@ -178,6 +181,12 @@ TEST_F(FPDFViewEmbeddertest, ViewerRef) {
 
   FPDF_PAGERANGE page_range = FPDF_VIEWERREF_GetPrintPageRange(document());
   EXPECT_TRUE(page_range);
+  EXPECT_EQ(4U, FPDF_VIEWERREF_GetPrintPageRangeCount(page_range));
+  EXPECT_EQ(0, FPDF_VIEWERREF_GetPrintPageRangeElement(page_range, 0));
+  EXPECT_EQ(2, FPDF_VIEWERREF_GetPrintPageRangeElement(page_range, 1));
+  EXPECT_EQ(4, FPDF_VIEWERREF_GetPrintPageRangeElement(page_range, 2));
+  EXPECT_EQ(4, FPDF_VIEWERREF_GetPrintPageRangeElement(page_range, 3));
+  EXPECT_EQ(-1, FPDF_VIEWERREF_GetPrintPageRangeElement(page_range, 4));
 }
 
 TEST_F(FPDFViewEmbeddertest, NamedDests) {
diff --git a/public/fpdfview.h b/public/fpdfview.h
index f8d6026292..7758facc39 100644
--- a/public/fpdfview.h
+++ b/public/fpdfview.h
@@ -10,6 +10,8 @@
 #ifndef PUBLIC_FPDFVIEW_H_
 #define PUBLIC_FPDFVIEW_H_
 
+#include <stddef.h>
+
 #if defined(_WIN32) && !defined(__WINDOWS__)
 #include <windows.h>
 #endif
@@ -1014,6 +1016,28 @@ FPDF_VIEWERREF_GetNumCopies(FPDF_DOCUMENT document);
 FPDF_EXPORT FPDF_PAGERANGE FPDF_CALLCONV
 FPDF_VIEWERREF_GetPrintPageRange(FPDF_DOCUMENT document);
 
+// Function: FPDF_VIEWERREF_GetPrintPageRangeCount
+//          Returns the number of elements in a FPDF_PAGERANGE.
+//          Experimental API.
+// Parameters:
+//          pagerange   -   Handle to the page range.
+// Return value:
+//          The number of elements in the page range. Returns 0 on error.
+FPDF_EXPORT size_t FPDF_CALLCONV
+FPDF_VIEWERREF_GetPrintPageRangeCount(FPDF_PAGERANGE pagerange);
+
+// Function: FPDF_VIEWERREF_GetPrintPageRangeElement
+//          Returns an element from a FPDF_PAGERANGE.
+//          Experimental API.
+// Parameters:
+//          pagerange   -   Handle to the page range.
+//          index       -   Index of the element.
+// Return value:
+//          The value of the element in the page range at a given index.
+//          Returns -1 on error.
+FPDF_EXPORT int FPDF_CALLCONV
+FPDF_VIEWERREF_GetPrintPageRangeElement(FPDF_PAGERANGE pagerange, size_t index);
+
 // Function: FPDF_VIEWERREF_GetDuplex
 //          Returns the paper handling option to be used when printing from
 //          the print dialog.