Add FORM_GetSelectedText() function.

This function copies the selected text from a form text field or
form combobox text field into the buffer parameter and returns the
length of the selected text string. When buffer is a nullptr or
buflen is less than the length of the selected text, this function
does not modify the buffer and only returns the selected text length.

BUG=chromium:59266

Change-Id: Ie77de38e45bbe6f9ea033826c961435304eedfc7
Reviewed-on: https://pdfium-review.googlesource.com/6413
Reviewed-by: dsinclair <dsinclair@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>

1 files changed, 7 insertions, 0 deletions

diff --git a/fpdfsdk/formfiller/cffl_interactiveformfiller.cpp b/fpdfsdk/formfiller/cffl_interactiveformfiller.cpp
index 7647fb19ff..69c74bc587 100644
--- a/fpdfsdk/formfiller/cffl_interactiveformfiller.cpp
+++ b/fpdfsdk/formfiller/cffl_interactiveformfiller.cpp
@@ -522,6 +522,13 @@ void CFFL_InteractiveFormFiller::RemoveFormFiller(CPDFSDK_Annot* pAnnot) {
     UnRegisterFormFiller(pAnnot);
 }
 
+CFX_WideString CFFL_InteractiveFormFiller::GetSelectedText(
+    CPDFSDK_Annot* pAnnot) {
+  ASSERT(pAnnot->GetPDFAnnot()->GetSubtype() == CPDF_Annot::Subtype::WIDGET);
+  CFFL_FormFiller* pFormFiller = GetFormFiller(pAnnot, false);
+  return pFormFiller ? pFormFiller->GetSelectedText(pAnnot) : CFX_WideString();
+}
+
 void CFFL_InteractiveFormFiller::UnRegisterFormFiller(CPDFSDK_Annot* pAnnot) {
   auto it = m_Maps.find(pAnnot);
   if (it == m_Maps.end())