-#define strappenda(a, b) \
- ({ \
- const char *_a_ = (a), *_b_ = (b); \
- char *_c_; \
- size_t _x_, _y_; \
- _x_ = strlen(_a_); \
- _y_ = strlen(_b_); \
- _c_ = alloca(_x_ + _y_ + 1); \
- strcpy(stpcpy(_c_, _a_), _b_); \
- _c_; \
+#define alloca_align(size, align) \
+ ({ \
+ void *_ptr_; \
+ size_t _mask_ = (align) - 1; \
+ _ptr_ = alloca((size) + _mask_); \
+ (void*)(((uintptr_t)_ptr_ + _mask_) & ~_mask_); \
+ })
+
+#define alloca0_align(size, align) \
+ ({ \
+ void *_new_; \
+ size_t _size_ = (size); \
+ _new_ = alloca_align(_size_, (align)); \
+ (void*)memset(_new_, 0, _size_); \
+ })
+
+#define strappenda(a, ...) \
+ ({ \
+ int _len = strlen(a); \
+ unsigned _i; \
+ char *_d_, *_p_; \
+ const char *_appendees_[] = { __VA_ARGS__ }; \
+ for (_i = 0; _i < ELEMENTSOF(_appendees_); _i++) \
+ _len += strlen(_appendees_[_i]); \
+ _d_ = alloca(_len + 1); \
+ _p_ = stpcpy(_d_, a); \
+ for (_i = 0; _i < ELEMENTSOF(_appendees_); _i++) \
+ _p_ = stpcpy(_p_, _appendees_[_i]); \
+ _d_; \