diff options
Diffstat (limited to 'mysql/mysys/my_malloc.c')
| -rw-r--r-- | mysql/mysys/my_malloc.c | 325 |
1 files changed, 325 insertions, 0 deletions
diff --git a/mysql/mysys/my_malloc.c b/mysql/mysys/my_malloc.c new file mode 100644 index 0000000..230ee5b --- /dev/null +++ b/mysql/mysys/my_malloc.c @@ -0,0 +1,325 @@ +/* Copyright (c) 2000, 2016, Oracle and/or its affiliates. All rights reserved. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; version 2 of the License. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ + +#include "mysys_priv.h" +#include "my_sys.h" +#include "mysys_err.h" +#include <m_string.h> +#include "my_thread_local.h" + +#ifdef HAVE_PSI_MEMORY_INTERFACE +#define USE_MALLOC_WRAPPER +#endif + +static void *my_raw_malloc(size_t size, myf my_flags); +static void my_raw_free(void *ptr); + +#ifdef USE_MALLOC_WRAPPER +struct my_memory_header +{ + PSI_memory_key m_key; + uint m_magic; + size_t m_size; + PSI_thread *m_owner; +}; +typedef struct my_memory_header my_memory_header; +#define HEADER_SIZE 32 + +#define MAGIC 1234 + +#define USER_TO_HEADER(P) \ + ( (my_memory_header*) (((char *) P) - HEADER_SIZE )) +#define HEADER_TO_USER(P) \ + ( ((char*) P) + HEADER_SIZE ) + +void * my_malloc(PSI_memory_key key, size_t size, myf flags) +{ + my_memory_header *mh; + size_t raw_size; + compile_time_assert(sizeof(my_memory_header) <= HEADER_SIZE); + + raw_size= HEADER_SIZE + size; + mh= (my_memory_header*) my_raw_malloc(raw_size, flags); + if (likely(mh != NULL)) + { + void *user_ptr; + mh->m_magic= MAGIC; + mh->m_size= size; + mh->m_key= PSI_MEMORY_CALL(memory_alloc)(key, size, & mh->m_owner); + user_ptr= HEADER_TO_USER(mh); + MEM_MALLOCLIKE_BLOCK(user_ptr, size, 0, (flags & MY_ZEROFILL)); + return user_ptr; + } + return NULL; +} + +void * +my_realloc(PSI_memory_key key, void *ptr, size_t size, myf flags) +{ + my_memory_header *old_mh; + size_t old_size; + size_t min_size; + void *new_ptr; + + if (ptr == NULL) + return my_malloc(key, size, flags); + + old_mh= USER_TO_HEADER(ptr); + DBUG_ASSERT((old_mh->m_key == key) || (old_mh->m_key == PSI_NOT_INSTRUMENTED)); + DBUG_ASSERT(old_mh->m_magic == MAGIC); + + old_size= old_mh->m_size; + + if (old_size == size) + return ptr; + + new_ptr= my_malloc(key, size, flags); + if (likely(new_ptr != NULL)) + { +#ifndef DBUG_OFF + my_memory_header *new_mh= USER_TO_HEADER(new_ptr); +#endif + + DBUG_ASSERT((new_mh->m_key == key) || (new_mh->m_key == PSI_NOT_INSTRUMENTED)); + DBUG_ASSERT(new_mh->m_magic == MAGIC); + DBUG_ASSERT(new_mh->m_size == size); + + min_size= (old_size < size) ? old_size : size; + memcpy(new_ptr, ptr, min_size); + my_free(ptr); + + return new_ptr; + } + return NULL; +} + +void my_claim(void *ptr) +{ + my_memory_header *mh; + + if (ptr == NULL) + return; + + mh= USER_TO_HEADER(ptr); + DBUG_ASSERT(mh->m_magic == MAGIC); + mh->m_key= PSI_MEMORY_CALL(memory_claim)(mh->m_key, mh->m_size, & mh->m_owner); +} + +void my_free(void *ptr) +{ + my_memory_header *mh; + + if (ptr == NULL) + return; + + mh= USER_TO_HEADER(ptr); + DBUG_ASSERT(mh->m_magic == MAGIC); + PSI_MEMORY_CALL(memory_free)(mh->m_key, mh->m_size, mh->m_owner); + /* Catch double free */ + mh->m_magic= 0xDEAD; + MEM_FREELIKE_BLOCK(ptr, 0); + my_raw_free(mh); +} + +#else + +void *my_malloc(PSI_memory_key key MY_ATTRIBUTE((unused)), + size_t size, myf my_flags) +{ + return my_raw_malloc(size, my_flags); +} + +static void *my_raw_realloc(void *oldpoint, size_t size, myf my_flags); + +void *my_realloc(PSI_memory_key key MY_ATTRIBUTE((unused)), + void *ptr, size_t size, myf flags) +{ + return my_raw_realloc(ptr, size, flags); +} + +void my_claim(void *ptr MY_ATTRIBUTE((unused))) +{ + /* Empty */ +} + +void my_free(void *ptr) +{ + my_raw_free(ptr); +} +#endif + + +/** + Allocate a sized block of memory. + + @param size The size of the memory block in bytes. + @param flags Failure action modifiers (bitmasks). + + @return A pointer to the allocated memory block, or NULL on failure. +*/ +static void *my_raw_malloc(size_t size, myf my_flags) +{ + void* point; + DBUG_ENTER("my_raw_malloc"); + DBUG_PRINT("my",("size: %lu my_flags: %d", (ulong) size, my_flags)); + + /* Safety */ + if (!size) + size=1; + +#if defined(MY_MSCRT_DEBUG) + if (my_flags & MY_ZEROFILL) + point= _calloc_dbg(size, 1, _CLIENT_BLOCK, __FILE__, __LINE__); + else + point= _malloc_dbg(size, _CLIENT_BLOCK, __FILE__, __LINE__); +#else + if (my_flags & MY_ZEROFILL) + point= calloc(size, 1); + else + point= malloc(size); +#endif + + DBUG_EXECUTE_IF("simulate_out_of_memory", + { + free(point); + point= NULL; + }); + DBUG_EXECUTE_IF("simulate_persistent_out_of_memory", + { + free(point); + point= NULL; + }); + + if (point == NULL) + { + set_my_errno(errno); + if (my_flags & MY_FAE) + error_handler_hook=fatal_error_handler_hook; + if (my_flags & (MY_FAE+MY_WME)) + my_error(EE_OUTOFMEMORY, MYF(ME_ERRORLOG + ME_FATALERROR),size); + DBUG_EXECUTE_IF("simulate_out_of_memory", + DBUG_SET("-d,simulate_out_of_memory");); + if (my_flags & MY_FAE) + exit(1); + } + + DBUG_PRINT("exit",("ptr: %p", point)); + DBUG_RETURN(point); +} + + +#ifndef USE_MALLOC_WRAPPER +/** + @brief wrapper around realloc() + + @param oldpoint pointer to currently allocated area + @param size new size requested, must be >0 + @param my_flags flags + + @note if size==0 realloc() may return NULL; my_realloc() treats this as an + error which is not the intention of realloc() +*/ +static void *my_raw_realloc(void *oldpoint, size_t size, myf my_flags) +{ + void *point; + DBUG_ENTER("my_realloc"); + DBUG_PRINT("my",("ptr: %p size: %lu my_flags: %d", oldpoint, + (ulong) size, my_flags)); + + DBUG_ASSERT(size > 0); + /* These flags are mutually exclusive. */ + DBUG_ASSERT(!((my_flags & MY_FREE_ON_ERROR) && + (my_flags & MY_HOLD_ON_ERROR))); + DBUG_EXECUTE_IF("simulate_out_of_memory", + point= NULL; + goto end;); + if (!oldpoint && (my_flags & MY_ALLOW_ZERO_PTR)) + DBUG_RETURN(my_raw_malloc(size, my_flags)); +#if defined(MY_MSCRT_DEBUG) + point= _realloc_dbg(oldpoint, size, _CLIENT_BLOCK, __FILE__, __LINE__); +#else + point= realloc(oldpoint, size); +#endif +#ifndef DBUG_OFF +end: +#endif + if (point == NULL) + { + if (my_flags & MY_HOLD_ON_ERROR) + DBUG_RETURN(oldpoint); + if (my_flags & MY_FREE_ON_ERROR) + my_free(oldpoint); + set_my_errno(errno); + if (my_flags & (MY_FAE+MY_WME)) + my_error(EE_OUTOFMEMORY, MYF(ME_FATALERROR), + size); + DBUG_EXECUTE_IF("simulate_out_of_memory", + DBUG_SET("-d,simulate_out_of_memory");); + } + DBUG_PRINT("exit",("ptr: %p", point)); + DBUG_RETURN(point); +} +#endif + +/** + Free memory allocated with my_raw_malloc. + + @remark Relies on free being able to handle a NULL argument. + + @param ptr Pointer to the memory allocated by my_raw_malloc. +*/ +static void my_raw_free(void *ptr) +{ + DBUG_ENTER("my_free"); + DBUG_PRINT("my",("ptr: %p", ptr)); +#if defined(MY_MSCRT_DEBUG) + _free_dbg(ptr, _CLIENT_BLOCK); +#else + free(ptr); +#endif + DBUG_VOID_RETURN; +} + + +void *my_memdup(PSI_memory_key key, const void *from, size_t length, myf my_flags) +{ + void *ptr; + if ((ptr= my_malloc(key, length, my_flags)) != 0) + memcpy(ptr, from, length); + return ptr; +} + + +char *my_strdup(PSI_memory_key key, const char *from, myf my_flags) +{ + char *ptr; + size_t length= strlen(from)+1; + if ((ptr= (char*) my_malloc(key, length, my_flags))) + memcpy(ptr, from, length); + return ptr; +} + + +char *my_strndup(PSI_memory_key key, const char *from, size_t length, myf my_flags) +{ + char *ptr; + if ((ptr= (char*) my_malloc(key, length+1, my_flags))) + { + memcpy(ptr, from, length); + ptr[length]= 0; + } + return ptr; +} + |