DRTVWR-575: Address review comments on Xcode 14.1 type tweaks.

Introduce LLSD template constructors and assignment operators to disambiguate
construction or assignment from any integer type to Integer, likewise any
floating point type to Real. Use new narrow() function to validate
conversions.

For LLSD method parameters converted from LLSD::Integer to size_t, where the
method previously checked for a negative argument, make it now check for
size_t converted from negative: in other words, more than S32_MAX. The risk of
having a parameter forced from negative to unsigned exceeds the risk of a
valid length or index over that max.

In lltracerecording.cpp's PeriodicRecording, now that mCurPeriod and
mNumRecordedPeriods are size_t instead of S32, defend against subtracting 1
from 0.

Use narrow() to validate newly-introduced narrowing conversions.

Make llclamp() return the type of the raw input value, even if the types of
the boundary values differ.

std::ostream::tellp() no longer returns a value we can directly report as a
number. Cast to U64.

1 files changed, 18 insertions, 4 deletions

diff --git a/indra/llcommon/llsd.cpp b/indra/llcommon/llsd.cpp
index 8772178b05..a645e624f8 100644
--- a/indra/llcommon/llsd.cpp
+++ b/indra/llcommon/llsd.cpp
@@ -36,6 +36,18 @@
 #include "llsdserialize.h"
 #include "stringize.h"
 
+#include <limits>
+
+// Defend against a caller forcibly passing a negative number into an unsigned
+// size_t index param
+inline
+bool was_negative(size_t i)
+{
+    return (i > std::numeric_limits<int>::max());
+}
+#define NEGATIVE_EXIT(i) if (was_negative(i)) return
+#define NEGATIVE_RETURN(i, result) NEGATIVE_EXIT(i) (result)
+
 #ifndef LL_RELEASE_FOR_DOWNLOAD
 #define NAME_UNNAMED_NAMESPACE
 #endif
@@ -555,6 +567,7 @@ namespace
 
 	LLSD ImplArray::get(size_t i) const
 	{
+		NEGATIVE_RETURN(i, LLSD());
 		DataVector::size_type index = i;
 
 		return (index < mData.size()) ? mData[index] : LLSD();
@@ -562,6 +575,7 @@ namespace
 
 	void ImplArray::set(size_t i, const LLSD& v)
 	{
+		NEGATIVE_EXIT(i);
 		DataVector::size_type index = i;
 
 		if (index >= mData.size())
@@ -574,6 +588,7 @@ namespace
 
 	void ImplArray::insert(size_t i, const LLSD& v)
 	{
+		NEGATIVE_EXIT(i);
 		DataVector::size_type index = i;
 
 		if (index >= mData.size())	// tbd - sanity check limit for index ?
@@ -592,6 +607,7 @@ namespace
 
 	void ImplArray::erase(size_t i)
 	{
+		NEGATIVE_EXIT(i);
 		DataVector::size_type index = i;
 
 		if (index < mData.size())
@@ -602,7 +618,7 @@ namespace
 
 	LLSD& ImplArray::ref(size_t i)
 	{
-		DataVector::size_type index = i;
+		DataVector::size_type index = was_negative(i)? 0 : i;
 
 		if (index >= mData.size())
 		{
@@ -614,6 +630,7 @@ namespace
 
 	const LLSD& ImplArray::ref(size_t i) const
 	{
+		NEGATIVE_RETURN(i, undef());
 		DataVector::size_type index = i;
 
 		if (index >= mData.size())
@@ -833,9 +850,6 @@ LLSD::LLSD(const Date& v) : impl(0)		{ ALLOC_LLSD_OBJECT;	assign(v); }
 LLSD::LLSD(const URI& v) : impl(0)		{ ALLOC_LLSD_OBJECT;	assign(v); }
 LLSD::LLSD(const Binary& v) : impl(0)	{ ALLOC_LLSD_OBJECT;	assign(v); }
 
-// Convenience Constructors
-LLSD::LLSD(F32 v) : impl(0)				{ ALLOC_LLSD_OBJECT;	assign((Real)v); }
-
 // Scalar Assignment
 void LLSD::assign(Boolean v)			{ safe(impl).assign(impl, v); }
 void LLSD::assign(Integer v)			{ safe(impl).assign(impl, v); }