Add FPDFAnnot_CountAttachmentPoints

This CL adds a function to the API that returns the number of quadpoint
sets.

Change-Id: I999bc567a4c98f6c32e87810e7ecfbb634c7b677
Reviewed-on: https://pdfium-review.googlesource.com/29130
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>

3 files changed, 34 insertions, 3 deletions

diff --git a/fpdfsdk/fpdfannot.cpp b/fpdfsdk/fpdfannot.cpp
index b5dccaade1..c52807148e 100644
--- a/fpdfsdk/fpdfannot.cpp
+++ b/fpdfsdk/fpdfannot.cpp
@@ -583,7 +583,7 @@ FPDFAnnot_HasAttachmentPoints(FPDF_ANNOTATION annot) {
 FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV
 FPDFAnnot_SetAttachmentPoints(FPDF_ANNOTATION annot,
                               const FS_QUADPOINTSF* quad_points) {
-  if (!annot || !quad_points || !FPDFAnnot_HasAttachmentPoints(annot))
+  if (!FPDFAnnot_HasAttachmentPoints(annot) || !quad_points)
     return false;
 
   CPDF_Dictionary* pAnnotDict =
@@ -621,10 +621,21 @@ FPDFAnnot_SetAttachmentPoints(FPDF_ANNOTATION annot,
   return true;
 }
 
+FPDF_EXPORT size_t FPDF_CALLCONV
+FPDFAnnot_CountAttachmentPoints(FPDF_ANNOTATION annot) {
+  if (!FPDFAnnot_HasAttachmentPoints(annot))
+    return 0;
+
+  CPDF_Dictionary* pAnnotDict =
+      CPDFAnnotContextFromFPDFAnnotation(annot)->GetAnnotDict();
+  const CPDF_Array* pArray = GetQuadPointsArrayFromDictionary(pAnnotDict);
+  return pArray ? pArray->GetCount() / 8 : 0;
+}
+
 FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV
 FPDFAnnot_GetAttachmentPoints(FPDF_ANNOTATION annot,
                               FS_QUADPOINTSF* quad_points) {
-  if (!annot || !quad_points || !FPDFAnnot_HasAttachmentPoints(annot))
+  if (!FPDFAnnot_HasAttachmentPoints(annot) || !quad_points)
     return false;
 
   return GetQuadPointsFromDictionary(
diff --git a/fpdfsdk/fpdfannot_embeddertest.cpp b/fpdfsdk/fpdfannot_embeddertest.cpp
index b96460a395..552398c41f 100644
--- a/fpdfsdk/fpdfannot_embeddertest.cpp
+++ b/fpdfsdk/fpdfannot_embeddertest.cpp
@@ -47,7 +47,7 @@ TEST_F(FPDFAnnotEmbeddertest, RenderAnnotWithOnlyRolloverAP) {
 
 TEST_F(FPDFAnnotEmbeddertest, RenderMultilineMarkupAnnotWithoutAP) {
   const char md5_hash[] = "76512832d88017668d9acc7aacd13dae";
-  // Open a file with two multiline markup annotations.
+  // Open a file with multiline markup annotations.
   ASSERT_TRUE(OpenDocument("annotation_markup_multiline_no_ap.pdf"));
   FPDF_PAGE page = LoadPage(0);
   ASSERT_TRUE(page);
@@ -471,6 +471,25 @@ TEST_F(FPDFAnnotEmbeddertest, ModifyRectQuadpointsWithAP) {
   UnloadPage(page);
 }
 
+TEST_F(FPDFAnnotEmbeddertest, CountAttachmentPoints) {
+  // Open a file with multiline markup annotations.
+  ASSERT_TRUE(OpenDocument("annotation_markup_multiline_no_ap.pdf"));
+  FPDF_PAGE page = LoadPage(0);
+  ASSERT_TRUE(page);
+  {
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(page, 0));
+    ASSERT_TRUE(annot);
+
+    // This is a three line annotation.
+    EXPECT_EQ(3u, FPDFAnnot_CountAttachmentPoints(annot.get()));
+  }
+  UnloadPage(page);
+
+  // null annotation should return 0
+  EXPECT_EQ(0u, FPDFAnnot_CountAttachmentPoints(nullptr));
+}
+
 TEST_F(FPDFAnnotEmbeddertest, RemoveAnnotation) {
   // Open a file with 3 annotations on its first page.
   ASSERT_TRUE(OpenDocument("annotation_ink_multiple.pdf"));
diff --git a/fpdfsdk/fpdfview_c_api_test.c b/fpdfsdk/fpdfview_c_api_test.c
index 2a0b230ca5..201fd90669 100644
--- a/fpdfsdk/fpdfview_c_api_test.c
+++ b/fpdfsdk/fpdfview_c_api_test.c
@@ -55,6 +55,7 @@ int CheckPDFiumCApi() {
     CHK(FPDFAnnot_GetColor);
     CHK(FPDFAnnot_HasAttachmentPoints);
     CHK(FPDFAnnot_SetAttachmentPoints);
+    CHK(FPDFAnnot_CountAttachmentPoints);
     CHK(FPDFAnnot_GetAttachmentPoints);
     CHK(FPDFAnnot_SetRect);
     CHK(FPDFAnnot_GetRect);