From 61fe5f1eee4cb95ca2625580c009d6c9aa7040a7 Mon Sep 17 00:00:00 2001 From: Thomas Braun Date: Fri, 30 Aug 2019 12:39:46 +0200 Subject: [PATCH] input_buffer_adapter: Fix handling of nullptr input Clang UBSAN currently complains that the char * to input_buffer_adapter is a nullptr. Turns out it is actually required to accept nullptr, see for example line 415 in input_adapters.hpp ... // the address of first cannot be used: use nullptr ia = std::make_shared(nullptr, len); .... Therefore we have to handle it gracefully here. We now also ignore the length parameter l if b is a nullptr. --- include/nlohmann/detail/input/input_adapters.hpp | 4 ++-- single_include/nlohmann/json.hpp | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/include/nlohmann/detail/input/input_adapters.hpp b/include/nlohmann/detail/input/input_adapters.hpp index b7b11de0..9512a771 100644 --- a/include/nlohmann/detail/input/input_adapters.hpp +++ b/include/nlohmann/detail/input/input_adapters.hpp @@ -131,9 +131,8 @@ class input_stream_adapter : public input_adapter_protocol class input_buffer_adapter : public input_adapter_protocol { public: - JSON_HEDLEY_NON_NULL(2) input_buffer_adapter(const char* b, const std::size_t l) noexcept - : cursor(b), limit(b + l) + : cursor(b), limit(b == nullptr ? nullptr : (b + l)) {} // delete because of pointer members @@ -147,6 +146,7 @@ class input_buffer_adapter : public input_adapter_protocol { if (JSON_HEDLEY_LIKELY(cursor < limit)) { + assert(cursor != nullptr and limit != nullptr); return std::char_traits::to_int_type(*(cursor++)); } diff --git a/single_include/nlohmann/json.hpp b/single_include/nlohmann/json.hpp index 2a32a829..4bbe2707 100644 --- a/single_include/nlohmann/json.hpp +++ b/single_include/nlohmann/json.hpp @@ -3882,9 +3882,8 @@ class input_stream_adapter : public input_adapter_protocol class input_buffer_adapter : public input_adapter_protocol { public: - JSON_HEDLEY_NON_NULL(2) input_buffer_adapter(const char* b, const std::size_t l) noexcept - : cursor(b), limit(b + l) + : cursor(b), limit(b == nullptr ? nullptr : (b + l)) {} // delete because of pointer members @@ -3898,6 +3897,7 @@ class input_buffer_adapter : public input_adapter_protocol { if (JSON_HEDLEY_LIKELY(cursor < limit)) { + assert(cursor != nullptr and limit != nullptr); return std::char_traits::to_int_type(*(cursor++)); }