Add FPDFAnnot_GetFormFieldAlternateName() API
This is similar to FPDFAnnot_GetFormFieldName() and allows getting the
alternate name. Such names are used e.g. for accessibility purposes.
Bug: pdfium:1892
Change-Id: I95dc771af64d6091b742f1da21e50a99327e015b
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/98210
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Miklos V <miklos.vajna@collabora.com>
diff --git a/fpdfsdk/fpdf_annot.cpp b/fpdfsdk/fpdf_annot.cpp
index 28661ec..9861b81 100644
--- a/fpdfsdk/fpdf_annot.cpp
+++ b/fpdfsdk/fpdf_annot.cpp
@@ -1264,6 +1264,19 @@
}
FPDF_EXPORT unsigned long FPDF_CALLCONV
+FPDFAnnot_GetFormFieldAlternateName(FPDF_FORMHANDLE hHandle,
+ FPDF_ANNOTATION annot,
+ FPDF_WCHAR* buffer,
+ unsigned long buflen) {
+ const CPDF_FormField* pFormField = GetFormField(hHandle, annot);
+ if (!pFormField)
+ return 0;
+
+ return Utf16EncodeMaybeCopyAndReturnLength(pFormField->GetAlternateName(),
+ buffer, buflen);
+}
+
+FPDF_EXPORT unsigned long FPDF_CALLCONV
FPDFAnnot_GetFormFieldValue(FPDF_FORMHANDLE hHandle,
FPDF_ANNOTATION annot,
FPDF_WCHAR* buffer,
diff --git a/fpdfsdk/fpdf_annot_embeddertest.cpp b/fpdfsdk/fpdf_annot_embeddertest.cpp
index 0328f39..8f3cf43 100644
--- a/fpdfsdk/fpdf_annot_embeddertest.cpp
+++ b/fpdfsdk/fpdf_annot_embeddertest.cpp
@@ -3650,6 +3650,35 @@
UnloadPage(page);
}
+TEST_F(FPDFAnnotEmbedderTest, FormFieldAlternateName) {
+ ASSERT_TRUE(OpenDocument("click_form.pdf"));
+ FPDF_PAGE page = LoadPage(0);
+ ASSERT_TRUE(page);
+ EXPECT_EQ(8, FPDFPage_GetAnnotCount(page));
+
+ {
+ ScopedFPDFAnnotation annot(FPDFPage_GetAnnot(page, 0));
+ ASSERT_TRUE(annot);
+
+ // FPDFAnnot_GetFormFieldAlternateName() positive testing.
+ unsigned long length_bytes = FPDFAnnot_GetFormFieldAlternateName(
+ form_handle(), annot.get(), nullptr, 0);
+ ASSERT_EQ(34u, length_bytes);
+ std::vector<FPDF_WCHAR> buf = GetFPDFWideStringBuffer(length_bytes);
+ EXPECT_EQ(34u, FPDFAnnot_GetFormFieldAlternateName(
+ form_handle(), annot.get(), buf.data(), length_bytes));
+ EXPECT_EQ(L"readOnlyCheckbox", GetPlatformWString(buf.data()));
+
+ // FPDFAnnot_GetFormFieldAlternateName() negative testing.
+ EXPECT_EQ(0u, FPDFAnnot_GetFormFieldAlternateName(form_handle(), nullptr,
+ nullptr, 0));
+ EXPECT_EQ(0u, FPDFAnnot_GetFormFieldAlternateName(nullptr, annot.get(),
+ nullptr, 0));
+ }
+
+ UnloadPage(page);
+}
+
// Due to https://crbug.com/pdfium/570, the AnnotationBorder test above cannot
// actually render the line annotations inside line_annot.pdf. For now, use a
// square annotation in annots.pdf for testing.
diff --git a/fpdfsdk/fpdf_view_c_api_test.c b/fpdfsdk/fpdf_view_c_api_test.c
index 7951525..0f656ae 100644
--- a/fpdfsdk/fpdf_view_c_api_test.c
+++ b/fpdfsdk/fpdf_view_c_api_test.c
@@ -55,6 +55,7 @@
CHK(FPDFAnnot_GetFormAdditionalActionJavaScript);
CHK(FPDFAnnot_GetFormControlCount);
CHK(FPDFAnnot_GetFormControlIndex);
+ CHK(FPDFAnnot_GetFormFieldAlternateName);
CHK(FPDFAnnot_GetFormFieldAtPoint);
CHK(FPDFAnnot_GetFormFieldExportValue);
CHK(FPDFAnnot_GetFormFieldFlags);
diff --git a/public/fpdf_annot.h b/public/fpdf_annot.h
index 0c0302c..333a6b2 100644
--- a/public/fpdf_annot.h
+++ b/public/fpdf_annot.h
@@ -722,6 +722,26 @@
unsigned long buflen);
// Experimental API.
+// Gets the alternate name of |annot|, which is an interactive form annotation.
+// |buffer| is only modified if |buflen| is longer than the length of contents.
+// In case of error, nothing will be added to |buffer| and the return value will
+// be 0. Note that return value of empty string is 2 for "\0\0".
+//
+// hHandle - handle to the form fill module, returned by
+// FPDFDOC_InitFormFillEnvironment().
+// annot - handle to an interactive form annotation.
+// buffer - buffer for holding the alternate name string, encoded in
+// UTF-16LE.
+// buflen - length of the buffer in bytes.
+//
+// Returns the length of the string value in bytes.
+FPDF_EXPORT unsigned long FPDF_CALLCONV
+FPDFAnnot_GetFormFieldAlternateName(FPDF_FORMHANDLE hHandle,
+ FPDF_ANNOTATION annot,
+ FPDF_WCHAR* buffer,
+ unsigned long buflen);
+
+// Experimental API.
// Gets the form field type of |annot|, which is an interactive form annotation.
//
// hHandle - handle to the form fill module, returned by
