From a297e4a5bf5f6a8e9ba2a811f36a1a885131f66d Mon Sep 17 00:00:00 2001 From: Adam Ierymenko Date: Wed, 8 Jul 2015 09:12:51 -0700 Subject: Add build def ZT_NO_TYPE_PUNNING, which when defined disables type punning code that might cause unaligned access errors on architectures that care (e.g. Android/ARM) --- node/Buffer.hpp | 26 +++++++++++++++++++++++--- 1 file changed, 23 insertions(+), 3 deletions(-) (limited to 'node/Buffer.hpp') diff --git a/node/Buffer.hpp b/node/Buffer.hpp index a4921b84..789b835a 100644 --- a/node/Buffer.hpp +++ b/node/Buffer.hpp @@ -39,7 +39,7 @@ #include "Constants.hpp" #include "Utils.hpp" -#ifdef __GNUC__ +#if defined(__GNUC__) && (!defined(ZT_NO_TYPE_PUNNING)) #define ZT_VAR_MAY_ALIAS __attribute__((__may_alias__)) #else #define ZT_VAR_MAY_ALIAS @@ -204,15 +204,19 @@ public: { if ((i + sizeof(T)) > _l) throw std::out_of_range("Buffer: setAt() beyond end of data"); +#ifdef ZT_NO_TYPE_PUNNING + uint8_t *p = reinterpret_cast(_b + i); + for(unsigned int x=1;x<=sizeof(T);++x) + *(p++) = (uint8_t)(v >> (8 * (sizeof(T) - x))); +#else T *const ZT_VAR_MAY_ALIAS p = reinterpret_cast(_b + i); *p = Utils::hton(v); +#endif } /** * Get a primitive integer value at a given position * - * This behaves like set() in reverse. - * * @param i Index to get integer * @tparam T Integer type (e.g. uint16_t, int64_t) * @return Integer value @@ -223,8 +227,18 @@ public: { if ((i + sizeof(T)) > _l) throw std::out_of_range("Buffer: at() beyond end of data"); +#ifdef ZT_NO_TYPE_PUNNING + T v = 0; + const uint8_t *p = reinterpret_cast(_b + i); + for(unsigned int x=0;x(_b + i); return Utils::ntoh(*p); +#endif } /** @@ -240,8 +254,14 @@ public: { if ((_l + sizeof(T)) > C) throw std::out_of_range("Buffer: append beyond capacity"); +#ifdef ZT_NO_TYPE_PUNNING + uint8_t *p = reinterpret_cast(_b + _l); + for(unsigned int x=1;x<=sizeof(T);++x) + *(p++) = (uint8_t)(v >> (8 * (sizeof(T) - x))); +#else T *const ZT_VAR_MAY_ALIAS p = reinterpret_cast(_b + _l); *p = Utils::hton(v); +#endif _l += sizeof(T); } -- cgit v1.2.3