Bugs in CJS_PublicMethods::ParseNumber().

Fix the bugs by removing ParseNumber() entirely.

For PDFium's JavaScript bindings, we want to get out of the
numeric conversion business and inflict that on V8 as
possible, avoiding platform-specific issue in strtod().

For other uses, there is a FX_atof() which is similarly
buggy, but we can consolidate the use.  Add an overloaded
FX_atof() to handle wide strings more simply.

BUG=pdfium:361
R=jochen@chromium.org

Review URL: https://codereview.chromium.org/1586203006 .

1 files changed, 20 insertions, 10 deletions

diff --git a/fpdfsdk/src/javascript/JS_Value.cpp b/fpdfsdk/src/javascript/JS_Value.cpp
index bd00adcf49..cfa565e4d4 100644
--- a/fpdfsdk/src/javascript/JS_Value.cpp
+++ b/fpdfsdk/src/javascript/JS_Value.cpp
@@ -19,8 +19,6 @@ static double GetNan() {
   return *(double*)g_nan;
 }
 
-/* ---------------------------- CJS_Value ---------------------------- */
-
 CJS_Value::CJS_Value(CJS_Runtime* pRuntime)
     : m_eType(VT_unknown), m_pJSRuntime(pRuntime) {
 }
@@ -98,9 +96,6 @@ void CJS_Value::Detach() {
   m_eType = VT_unknown;
 }
 
-/* ----------------------------------------------------------------------------------------
- */
-
 int CJS_Value::ToInt() const {
   return FXJS_ToInt32(m_pJSRuntime->GetIsolate(), m_pValue);
 }
@@ -146,8 +141,26 @@ v8::Local<v8::Array> CJS_Value::ToV8Array() const {
   return v8::Local<v8::Array>();
 }
 
-/* ----------------------------------------------------------------------------------------
- */
+void CJS_Value::MaybeCoerceToNumber() {
+  bool bAllowNaN = false;
+  if (m_eType == VT_string) {
+    CFX_ByteString bstr = ToCFXByteString();
+    if (bstr.GetLength() == 0)
+      return;
+    if (bstr == "NaN")
+      bAllowNaN = true;
+  }
+  v8::TryCatch(m_pJSRuntime->GetIsolate());
+  v8::MaybeLocal<v8::Number> maybeNum =
+      m_pValue->ToNumber(m_pJSRuntime->GetIsolate()->GetCurrentContext());
+  if (maybeNum.IsEmpty())
+    return;
+  v8::Local<v8::Number> num = maybeNum.ToLocalChecked();
+  if (std::isnan(num->Value()) && !bAllowNaN)
+    return;
+  m_pValue = num;
+  m_eType = VT_number;
+}
 
 void CJS_Value::operator=(int iValue) {
   m_pValue = FXJS_NewNumber(m_pJSRuntime->GetIsolate(), iValue);
@@ -217,9 +230,6 @@ void CJS_Value::operator=(CJS_Value value) {
   m_pJSRuntime = value.m_pJSRuntime;
 }
 
-/* ----------------------------------------------------------------------------------------
- */
-
 CJS_Value::Type CJS_Value::GetType() const {
   if (m_pValue.IsEmpty())
     return VT_unknown;