From e77337588e75adc6e6b8477a8dbe9d1ea8f25c8c Mon Sep 17 00:00:00 2001 From: Lioncash Date: Wed, 15 Apr 2020 14:21:22 -0400 Subject: file_util: Early-exit in WriteArray and ReadArray if specified lengths are zero It's undefined behavior to pass a null pointer to std::fread and std::fwrite, even if the length passed in is zero, so we must perform the precondition checking ourselves. A common case where this can occur is when passing in the data of an empty std::vector and size, as an empty vector will typically have a null internal buffer. While we're at it, we can move the implementation out of line and add debug checks against passing in nullptr to std::fread and std::fwrite. --- src/common/file_util.h | 14 +++++--------- 1 file changed, 5 insertions(+), 9 deletions(-) (limited to 'src/common/file_util.h') diff --git a/src/common/file_util.h b/src/common/file_util.h index cde7ddf2d..f7a0c33fa 100644 --- a/src/common/file_util.h +++ b/src/common/file_util.h @@ -222,22 +222,15 @@ public: static_assert(std::is_trivially_copyable_v, "Given array does not consist of trivially copyable objects"); - if (!IsOpen()) { - return std::numeric_limits::max(); - } - - return std::fread(data, sizeof(T), length, m_file); + return ReadImpl(data, length, sizeof(T)); } template std::size_t WriteArray(const T* data, std::size_t length) { static_assert(std::is_trivially_copyable_v, "Given array does not consist of trivially copyable objects"); - if (!IsOpen()) { - return std::numeric_limits::max(); - } - return std::fwrite(data, sizeof(T), length, m_file); + return WriteImpl(data, length, sizeof(T)); } template @@ -278,6 +271,9 @@ public: } private: + std::size_t ReadImpl(void* data, std::size_t length, std::size_t data_size) const; + std::size_t WriteImpl(const void* data, std::size_t length, std::size_t data_size); + std::FILE* m_file = nullptr; }; -- cgit v1.2.3