diff options
Diffstat (limited to 'include/ruby/internal/xmalloc.h')
| -rw-r--r-- | include/ruby/internal/xmalloc.h | 151 |
1 files changed, 151 insertions, 0 deletions
diff --git a/include/ruby/internal/xmalloc.h b/include/ruby/internal/xmalloc.h index 132bc478ce..2551609123 100644 --- a/include/ruby/internal/xmalloc.h +++ b/include/ruby/internal/xmalloc.h @@ -57,6 +57,10 @@ #define xrealloc2 ruby_xrealloc2 /**< @old{ruby_xrealloc2} */ #define xfree ruby_xfree /**< @old{ruby_xfree} */ +#define xfree_sized ruby_xfree_sized +#define xrealloc_sized ruby_xrealloc_sized +#define xrealloc2_sized ruby_xrealloc2_sized + RBIMPL_SYMBOL_EXPORT_BEGIN() RBIMPL_ATTR_NODISCARD() @@ -196,6 +200,58 @@ RBIMPL_ATTR_NOEXCEPT(realloc(ptr, newsiz)) RBIMPL_ATTR_NODISCARD() RBIMPL_ATTR_RETURNS_NONNULL() +RBIMPL_ATTR_ALLOC_SIZE((2)) +/** + * Identical to ruby_xrealloc(), except that it takes the old storage size + * as third argument. + * + * @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. + * @param[in] oldsiz Existing 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. + * @pre The passed oldsiz must be exactly equal to the size the pointer + * was allocated with. + * Passing an incorrect oldsiz is undefined behavior, which may + * cause memory leaks or crashes. + * @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_sized(void *ptr, size_t newsiz, size_t oldsiz) +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 @@ -251,6 +307,64 @@ void *ruby_xrealloc2(void *ptr, size_t newelems, size_t newsiz) RBIMPL_ATTR_NOEXCEPT(realloc(ptr, newelems * newsiz)) ; +RBIMPL_ATTR_NODISCARD() +RBIMPL_ATTR_RETURNS_NONNULL() +RBIMPL_ATTR_ALLOC_SIZE((2,3)) +/** + * Identical to ruby_xrealloc2(), except it takes the old elements count. + * + * 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. + * @param[in] oldelems The number of elements the pointer was + * previously allocated with. + * @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. + * @pre The passed oldelems must be exactly equal to the number of + * elements the pointer was allocated with. + * Passing an incorrect oldelems is undefined behavior, which may + * cause memory leaks or crashes. + * @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_sized(void *ptr, size_t newelems, size_t newsiz, size_t oldelems) +RBIMPL_ATTR_NOEXCEPT(realloc(ptr, newelems * newsiz)) +; + /** * Deallocates a storage instance. * @@ -283,6 +397,43 @@ void ruby_xfree(void *ptr) RBIMPL_ATTR_NOEXCEPT(free(ptr)) ; +/** + * Deallocates a storage instance of a specific ssize. + * + * @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. + * @pre The passed size must be exactly equal to the size the pointer + * was allocated with. + * Passing an incorrect size is undefined behavior, which may + * cause memory leaks or crashes. + * @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_sized(void *ptr, size_t size) +RBIMPL_ATTR_NOEXCEPT(free(ptr)) +; + + RBIMPL_SYMBOL_EXPORT_END() #endif /* RBIMPL_XMALLOC_H */ |