diff options
Diffstat (limited to 'include/ruby/internal/xmalloc.h')
| -rw-r--r-- | include/ruby/internal/xmalloc.h | 309 |
1 files changed, 198 insertions, 111 deletions
diff --git a/include/ruby/internal/xmalloc.h b/include/ruby/internal/xmalloc.h index b0fe863139..132bc478ce 100644 --- a/include/ruby/internal/xmalloc.h +++ b/include/ruby/internal/xmalloc.h @@ -17,7 +17,7 @@ * recursively included from extension libraries written in C++. * Do not expect for instance `__VA_ARGS__` is always available. * We assume C99 for ruby itself but we don't assume languages of - * extension libraries. They could be written in C++98. + * extension libraries. They could be written in C++98. * @brief Declares ::ruby_xmalloc(). */ #include "ruby/internal/config.h" @@ -37,16 +37,25 @@ #include "ruby/internal/attr/returns_nonnull.h" #include "ruby/internal/dllexport.h" +/** + * @private + * @warning Do not touch this macro. + * @warning It is an implementation detail. + * @warning It was a failure at the first place to let you know about it. + * @warning The value of this macro must match for ruby itself and all + * extension libraries, otherwise serious memory corruption shall + * occur. + */ #ifndef USE_GC_MALLOC_OBJ_INFO_DETAILS # define USE_GC_MALLOC_OBJ_INFO_DETAILS 0 #endif -#define xmalloc ruby_xmalloc -#define xmalloc2 ruby_xmalloc2 -#define xcalloc ruby_xcalloc -#define xrealloc ruby_xrealloc -#define xrealloc2 ruby_xrealloc2 -#define xfree ruby_xfree +#define xmalloc ruby_xmalloc /**< @old{ruby_xmalloc} */ +#define xmalloc2 ruby_xmalloc2 /**< @old{ruby_xmalloc2} */ +#define xcalloc ruby_xcalloc /**< @old{ruby_xcalloc} */ +#define xrealloc ruby_xrealloc /**< @old{ruby_xrealloc} */ +#define xrealloc2 ruby_xrealloc2 /**< @old{ruby_xrealloc2} */ +#define xfree ruby_xfree /**< @old{ruby_xfree} */ RBIMPL_SYMBOL_EXPORT_BEGIN() @@ -54,6 +63,26 @@ RBIMPL_ATTR_NODISCARD() RBIMPL_ATTR_RESTRICT() RBIMPL_ATTR_RETURNS_NONNULL() RBIMPL_ATTR_ALLOC_SIZE((1)) +/** + * Allocates a storage instance. It is largely the same as system malloc(), + * except: + * + * - It raises Ruby exceptions instead of returning NULL, and + * - In case of `ENOMEM` it tries to GC to make some room. + * + * @param[in] size Requested amount of memory. + * @exception rb_eNoMemError No space left for `size` bytes allocation. + * @return A valid pointer to an allocated storage instance; which has at + * least `size` bytes width, with appropriate alignment detected by + * the underlying malloc() routine. + * @note It doesn't return NULL. + * @note Unlike some malloc() implementations, it allocates something and + * returns a meaningful value even when `size` is equal to zero. + * @warning The return value shall be invalidated exactly once by either + * ruby_xfree(), ruby_xrealloc(), or ruby_xrealloc2(). It is a + * failure to pass it to system free(), because the system and Ruby + * might or might not share the same malloc() implementation. + */ void *ruby_xmalloc(size_t size) RBIMPL_ATTR_NOEXCEPT(malloc(size)) ; @@ -62,6 +91,29 @@ RBIMPL_ATTR_NODISCARD() RBIMPL_ATTR_RESTRICT() RBIMPL_ATTR_RETURNS_NONNULL() RBIMPL_ATTR_ALLOC_SIZE((1,2)) +/** + * Identical to ruby_xmalloc(), except it allocates `nelems` * `elemsiz` bytes. + * This is needed because the multiplication could integer overflow. On such + * situations Ruby does not try to allocate at all but raises Ruby level + * exceptions instead. If there is no integer overflow the behaviour is + * exactly the same as `ruby_xmalloc(nelems*elemsiz)`. + * + * @param[in] nelems Number of elements. + * @param[in] elemsiz Size of an element. + * @exception rb_eNoMemError No space left for allocation. + * @exception rb_eArgError `nelems` * `elemsiz` would overflow. + * @return A valid pointer to an allocated storage instance; which has at + * least `nelems` * `elemsiz` bytes width, with appropriate + * alignment detected by the underlying malloc() routine. + * @note It doesn't return NULL. + * @note Unlike some malloc() implementations, it allocates something and + * returns a meaningful value even when `nelems` or `elemsiz` or + * both are zero. + * @warning The return value shall be invalidated exactly once by either + * ruby_xfree(), ruby_xrealloc(), or ruby_xrealloc2(). It is a + * failure to pass it to system free(), because the system and Ruby + * might or might not share the same malloc() implementation. + */ void *ruby_xmalloc2(size_t nelems, size_t elemsiz) RBIMPL_ATTR_NOEXCEPT(malloc(nelems * elemsiz)) ; @@ -70,6 +122,28 @@ RBIMPL_ATTR_NODISCARD() RBIMPL_ATTR_RESTRICT() RBIMPL_ATTR_RETURNS_NONNULL() RBIMPL_ATTR_ALLOC_SIZE((1,2)) +/** + * Identical to ruby_xmalloc2(), except it returns a zero-filled storage + * instance. It can also be seen as a routine identical to ruby_xmalloc(), + * except it calls calloc() instead of malloc(). + * + * @param[in] nelems Number of elements. + * @param[in] elemsiz Size of an element. + * @exception rb_eNoMemError No space left for allocation. + * @exception rb_eArgError `nelems` * `elemsiz` would overflow. + * @return A valid pointer to an allocated storage instance; which has at + * least `nelems` * `elemsiz` bytes width, with appropriate + * alignment detected by the underlying calloc() routine. + * @post The returned storage instance is filled with zeros. + * @note It doesn't return NULL. + * @note Unlike some calloc() implementations, it allocates something and + * returns a meaningful value even when `nelems` or `elemsiz` or + * both are zero. + * @warning The return value shall be invalidated exactly once by either + * ruby_xfree(), ruby_xrealloc(), or ruby_xrealloc2(). It is a + * failure to pass it to system free(), because the system and Ruby + * might or might not share the same malloc() implementation. + */ void *ruby_xcalloc(size_t nelems, size_t elemsiz) RBIMPL_ATTR_NOEXCEPT(calloc(nelems, elemsiz)) ; @@ -77,6 +151,45 @@ RBIMPL_ATTR_NOEXCEPT(calloc(nelems, elemsiz)) RBIMPL_ATTR_NODISCARD() RBIMPL_ATTR_RETURNS_NONNULL() RBIMPL_ATTR_ALLOC_SIZE((2)) +/** + * Resize the storage instance. + * + * @param[in] ptr A valid pointer to a storage instance that was + * previously returned from either: + * - ruby_xmalloc(), + * - ruby_xmalloc2(), + * - ruby_xcalloc(), + * - ruby_xrealloc(), or + * - ruby_xrealloc2(). + * @param[in] newsiz Requested new amount of memory. + * @exception rb_eNoMemError No space left for `newsiz` bytes allocation. + * @return A valid pointer to a (possibly newly allocated) storage + * instance; which has at least `newsiz` bytes width, with + * appropriate alignment detected by the underlying realloc() + * routine. + * @pre The passed pointer must point to a valid live storage instance. + * It is a failure to pass an already freed pointer. + * @post In case the function returns the passed pointer as-is, the + * storage instance that the pointer holds is either grown or + * shrunken to have at least `newsiz` bytes. Otherwise a valid + * pointer to a newly allocated storage instance is returned. In + * this case `ptr` is invalidated as if it was passed to + * ruby_xfree(). + * @note It doesn't return NULL. + * @warning Unlike some realloc() implementations, passing zero to `newsiz` + * is not the same as calling ruby_xfree(), because this function + * never returns NULL. Something meaningful still returns then. + * @warning It is a failure not to check the return value. Do not assume + * anything on it. It could be either identical to, or distinct + * form the passed argument. + * @warning Do not assume anything on the alignment of the return value. + * There is no guarantee that it inherits the passed argument's + * one. + * @warning The return value shall be invalidated exactly once by either + * ruby_xfree(), ruby_xrealloc(), or ruby_xrealloc2(). It is a + * failure to pass it to system free(), because the system and Ruby + * might or might not share the same malloc() implementation. + */ void *ruby_xrealloc(void *ptr, size_t newsiz) RBIMPL_ATTR_NOEXCEPT(realloc(ptr, newsiz)) ; @@ -84,118 +197,92 @@ RBIMPL_ATTR_NOEXCEPT(realloc(ptr, newsiz)) RBIMPL_ATTR_NODISCARD() RBIMPL_ATTR_RETURNS_NONNULL() RBIMPL_ATTR_ALLOC_SIZE((2,3)) +/** + * Identical to ruby_xrealloc(), except it resizes the given storage instance + * to `newelems` * `newsiz` bytes. This is needed because the multiplication + * could integer overflow. On such situations Ruby does not try to touch the + * contents of argument pointer at all but raises Ruby level exceptions + * instead. If there is no integer overflow the behaviour is exactly the same + * as `ruby_xrealloc(ptr,nelems*elemsiz)`. + * + * This is roughly the same as reallocarray() function that OpenBSD + * etc. provides, but also interacts with our GC. + * + * @param[in] ptr A valid pointer to a storage instance that was + * previously returned from either: + * - ruby_xmalloc(), + * - ruby_xmalloc2(), + * - ruby_xcalloc(), + * - ruby_xrealloc(), or + * - ruby_xrealloc2(). + * @param[in] newelems Requested new number of elements. + * @param[in] newsiz Requested new size of each element. + * @exception rb_eNoMemError No space left for allocation. + * @exception rb_eArgError `newelems` * `newsiz` would overflow. + * @return A valid pointer to a (possibly newly allocated) storage + * instance; which has at least `newelems` * `newsiz` bytes width, + * with appropriate alignment detected by the underlying realloc() + * routine. + * @pre The passed pointer must point to a valid live storage instance. + * It is a failure to pass an already freed pointer. + * @post In case the function returns the passed pointer as-is, the + * storage instance that the pointer holds is either grown or + * shrunken to have at least `newelems` * `newsiz` bytes. + * Otherwise a valid pointer to a newly allocated storage instance + * is returned. In this case `ptr` is invalidated as if it was + * passed to ruby_xfree(). + * @note It doesn't return NULL. + * @warning Unlike some realloc() implementations, passing zero to either + * `newelems` or `elemsiz` are not the same as calling + * ruby_xfree(), because this function never returns NULL. + * Something meaningful still returns then. + * @warning It is a failure not to check the return value. Do not assume + * anything on it. It could be either identical to, or distinct + * form the passed argument. + * @warning Do not assume anything on the alignment of the return value. + * There is no guarantee that it inherits the passed argument's + * one. + * @warning The return value shall be invalidated exactly once by either + * ruby_xfree(), ruby_xrealloc(), or ruby_xrealloc2(). It is a + * failure to pass it to system free(), because the system and Ruby + * might or might not share the same malloc() implementation. + */ void *ruby_xrealloc2(void *ptr, size_t newelems, size_t newsiz) RBIMPL_ATTR_NOEXCEPT(realloc(ptr, newelems * newsiz)) ; +/** + * Deallocates a storage instance. + * + * @param[out] ptr Either + * - NULL, or + * - a valid pointer previously returned from one of: + * - ruby_xmalloc(), + * - ruby_xmalloc2(), + * - ruby_xcalloc(), + * - ruby_xrealloc(), or + * - ruby_xrealloc2(). + * @pre The passed pointer must point to a valid live storage instance. + * It is a failure to pass an already freed pointer. + * @post The storage instance pointed by the passed pointer gets + * invalidated; it is no longer addressable. + * @warning Every single storage instance that was previously allocated by + * either ruby_xmalloc(), ruby_xmalloc2(), ruby_xcalloc(), + * ruby_xrealloc(), or ruby_xrealloc2() shall be invalidated + * exactly once by either passing it to ruby_xfree(), or passing + * it to either ruby_xrealloc(), ruby_xrealloc2() then check the + * return value for invalidation. + * @warning Do not pass anything other than pointers described above. For + * instance pointers returned from malloc() or mmap() shall not be + * passed to this function, because the underlying memory + * management mechanism could differ. + * @warning Do not pass any invalid pointers to this function e.g. by + * calling it twice with a same argument. + */ void ruby_xfree(void *ptr) RBIMPL_ATTR_NOEXCEPT(free(ptr)) ; -#if USE_GC_MALLOC_OBJ_INFO_DETAILS || defined(__DOXYGEN) -# define ruby_xmalloc(s1) ruby_xmalloc_with_location(s1, __FILE__, __LINE__) -# define ruby_xmalloc2(s1, s2) ruby_xmalloc2_with_location(s1, s2, __FILE__, __LINE__) -# define ruby_xcalloc(s1, s2) ruby_xcalloc_with_location(s1, s2, __FILE__, __LINE__) -# define ruby_xrealloc(ptr, s1) ruby_xrealloc_with_location(ptr, s1, __FILE__, __LINE__) -# define ruby_xrealloc2(ptr, s1, s2) ruby_xrealloc2_with_location(ptr, s1, s2, __FILE__, __LINE__) - -RBIMPL_ATTR_NODISCARD() -RBIMPL_ATTR_RESTRICT() -RBIMPL_ATTR_RETURNS_NONNULL() -RBIMPL_ATTR_ALLOC_SIZE((1)) -void *ruby_xmalloc_body(size_t size) -RBIMPL_ATTR_NOEXCEPT(malloc(size)) -; - -RBIMPL_ATTR_NODISCARD() -RBIMPL_ATTR_RESTRICT() -RBIMPL_ATTR_RETURNS_NONNULL() -RBIMPL_ATTR_ALLOC_SIZE((1,2)) -void *ruby_xmalloc2_body(size_t nelems, size_t elemsiz) -RBIMPL_ATTR_NOEXCEPT(malloc(nelems * elemsiz)) -; - -RBIMPL_ATTR_NODISCARD() -RBIMPL_ATTR_RESTRICT() -RBIMPL_ATTR_RETURNS_NONNULL() -RBIMPL_ATTR_ALLOC_SIZE((1,2)) -void *ruby_xcalloc_body(size_t nelems, size_t elemsiz) -RBIMPL_ATTR_NOEXCEPT(calloc(nelems, elemsiz)) -; - -RBIMPL_ATTR_NODISCARD() -RBIMPL_ATTR_RETURNS_NONNULL() -RBIMPL_ATTR_ALLOC_SIZE((2)) -void *ruby_xrealloc_body(void *ptr, size_t newsiz) -RBIMPL_ATTR_NOEXCEPT(realloc(ptr, newsiz)) -; - -RBIMPL_ATTR_NODISCARD() -RBIMPL_ATTR_RETURNS_NONNULL() -RBIMPL_ATTR_ALLOC_SIZE((2,3)) -void *ruby_xrealloc2_body(void *ptr, size_t newelems, size_t newsiz) -RBIMPL_ATTR_NOEXCEPT(realloc(ptr, newelems * newsiz)) -; - -RUBY_EXTERN const char *ruby_malloc_info_file; -RUBY_EXTERN int ruby_malloc_info_line; - -static inline void * -ruby_xmalloc_with_location(size_t s, const char *file, int line) -{ - void *ptr; - ruby_malloc_info_file = file; - ruby_malloc_info_line = line; - ptr = ruby_xmalloc_body(s); - ruby_malloc_info_file = NULL; - return ptr; -} - -static inline void * -ruby_xmalloc2_with_location(size_t s1, size_t s2, const char *file, int line) -{ - void *ptr; - ruby_malloc_info_file = file; - ruby_malloc_info_line = line; - ptr = ruby_xmalloc2_body(s1, s2); - ruby_malloc_info_file = NULL; - return ptr; -} - -static inline void * -ruby_xcalloc_with_location(size_t s1, size_t s2, const char *file, int line) -{ - void *ptr; - ruby_malloc_info_file = file; - ruby_malloc_info_line = line; - ptr = ruby_xcalloc_body(s1, s2); - ruby_malloc_info_file = NULL; - return ptr; -} - -static inline void * -ruby_xrealloc_with_location(void *ptr, size_t s, const char *file, int line) -{ - void *rptr; - ruby_malloc_info_file = file; - ruby_malloc_info_line = line; - rptr = ruby_xrealloc_body(ptr, s); - ruby_malloc_info_file = NULL; - return rptr; -} - -static inline void * -ruby_xrealloc2_with_location(void *ptr, size_t s1, size_t s2, const char *file, int line) -{ - void *rptr; - ruby_malloc_info_file = file; - ruby_malloc_info_line = line; - rptr = ruby_xrealloc2_body(ptr, s1, s2); - ruby_malloc_info_file = NULL; - return rptr; -} -#endif - RBIMPL_SYMBOL_EXPORT_END() #endif /* RBIMPL_XMALLOC_H */ |