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-rw-r--r--mysys/my_malloc.c251
1 files changed, 251 insertions, 0 deletions
diff --git a/mysys/my_malloc.c b/mysys/my_malloc.c
new file mode 100644
index 00000000..befdcb0e
--- /dev/null
+++ b/mysys/my_malloc.c
@@ -0,0 +1,251 @@
+/*
+ Copyright (c) 2000, 2013, Oracle and/or its affiliates
+ Copyright (c) 2009, 2014, SkySQL Ab
+
+ 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 02110-1335 USA */
+
+#include "mysys_priv.h"
+#include "mysys_err.h"
+#include <m_string.h>
+
+struct my_memory_header
+{
+ PSI_thread *m_owner;
+ size_t m_size;
+ PSI_memory_key m_key;
+};
+typedef struct my_memory_header my_memory_header;
+#define HEADER_SIZE 24
+
+#define USER_TO_HEADER(P) ((my_memory_header*)((char *)(P) - HEADER_SIZE))
+#define HEADER_TO_USER(P) ((char*)(P) + HEADER_SIZE)
+
+/**
+ Inform application that memory usage has changed
+
+ @param size Size of memory segment allocated or freed
+ @param flag 1 if thread specific (allocated by MY_THREAD_SPECIFIC),
+ 0 if system specific.
+
+ The type os size is long long, to be able to handle negative numbers to
+ decrement the memory usage
+
+ @return 0 - ok
+ 1 - failure, abort the allocation
+*/
+static void dummy(long long size __attribute__((unused)),
+ my_bool is_thread_specific __attribute__((unused)))
+{}
+
+static MALLOC_SIZE_CB update_malloc_size= dummy;
+
+void set_malloc_size_cb(MALLOC_SIZE_CB func)
+{
+ update_malloc_size= func ? func : dummy;
+}
+
+
+/**
+ 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.
+*/
+void *my_malloc(PSI_memory_key key, size_t size, myf my_flags)
+{
+ my_memory_header *mh;
+ void *point;
+ DBUG_ENTER("my_malloc");
+ DBUG_PRINT("my",("size: %zu flags: %lu", size, my_flags));
+ compile_time_assert(sizeof(my_memory_header) <= HEADER_SIZE);
+
+ if (!(my_flags & (MY_WME | MY_FAE)))
+ my_flags|= my_global_flags;
+
+ /* Safety */
+ if (!size)
+ size=1;
+ if (size > SIZE_T_MAX - 1024L*1024L*16L) /* Wrong call */
+ DBUG_RETURN(0);
+
+ /* We have to align size as we store MY_THREAD_SPECIFIC flag in the LSB */
+ size= ALIGN_SIZE(size);
+
+ if (DBUG_EVALUATE_IF("simulate_out_of_memory", 1, 0))
+ mh= NULL;
+ else
+ mh= (my_memory_header*) sf_malloc(size + HEADER_SIZE, my_flags);
+
+ if (mh == NULL)
+ {
+ 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_BELL+ME_ERROR_LOG+ME_FATAL),size);
+ if (my_flags & MY_FAE)
+ abort();
+ point= NULL;
+ }
+ else
+ {
+ int flag= MY_TEST(my_flags & MY_THREAD_SPECIFIC);
+ mh->m_size= size | flag;
+ mh->m_key= PSI_CALL_memory_alloc(key, size, & mh->m_owner);
+ update_malloc_size(size + HEADER_SIZE, flag);
+ point= HEADER_TO_USER(mh);
+ if (my_flags & MY_ZEROFILL)
+ bzero(point, size);
+ else
+ TRASH_ALLOC(point, size);
+ }
+ DBUG_PRINT("exit",("ptr: %p", point));
+ DBUG_RETURN(point);
+}
+
+
+/**
+ @brief wrapper around realloc()
+
+ @param old_point 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()
+*/
+void *my_realloc(PSI_memory_key key, void *old_point, size_t size, myf my_flags)
+{
+ my_memory_header *old_mh, *mh;
+ void *point;
+ size_t old_size;
+ my_bool old_flags;
+ DBUG_ENTER("my_realloc");
+ DBUG_PRINT("my",("ptr: %p size: %zu flags: %lu", old_point, size, my_flags));
+
+ DBUG_ASSERT(size > 0);
+ if (!old_point && (my_flags & MY_ALLOW_ZERO_PTR))
+ DBUG_RETURN(my_malloc(key, size, my_flags));
+
+ old_mh= USER_TO_HEADER(old_point);
+ old_size= old_mh->m_size & ~1;
+ old_flags= old_mh->m_size & 1;
+
+ DBUG_ASSERT(old_mh->m_key == key || old_mh->m_key == PSI_NOT_INSTRUMENTED);
+ DBUG_ASSERT(old_flags == MY_TEST(my_flags & MY_THREAD_SPECIFIC));
+
+ size= ALIGN_SIZE(size);
+ mh= sf_realloc(old_mh, size + HEADER_SIZE, my_flags);
+
+ if (mh == NULL)
+ {
+ if (size < old_size)
+ DBUG_RETURN(old_point);
+ my_errno=errno;
+ if (my_flags & MY_FREE_ON_ERROR)
+ {
+ /* my_free will take care of size accounting */
+ my_free(old_point);
+ old_point= 0;
+ }
+ if (my_flags & (MY_FAE+MY_WME))
+ my_error(EE_OUTOFMEMORY, MYF(ME_BELL + ME_FATAL), size);
+ point= NULL;
+ }
+ else
+ {
+ mh->m_size= size | old_flags;
+ mh->m_key= PSI_CALL_memory_realloc(key, old_size, size, & mh->m_owner);
+ update_malloc_size((longlong)size - (longlong)old_size, old_flags);
+ point= HEADER_TO_USER(mh);
+ }
+
+ DBUG_PRINT("exit",("ptr: %p", point));
+ DBUG_RETURN(point);
+}
+
+
+/**
+ Free memory allocated with my_malloc.
+
+ @param ptr Pointer to the memory allocated by my_malloc.
+*/
+void my_free(void *ptr)
+{
+ my_memory_header *mh;
+ size_t old_size;
+ my_bool old_flags;
+ DBUG_ENTER("my_free");
+ DBUG_PRINT("my",("ptr: %p", ptr));
+
+ if (ptr == NULL)
+ DBUG_VOID_RETURN;
+
+ mh= USER_TO_HEADER(ptr);
+ old_size= mh->m_size & ~1;
+ old_flags= mh->m_size & 1;
+ PSI_CALL_memory_free(mh->m_key, old_size, mh->m_owner);
+
+ update_malloc_size(- (longlong) old_size - HEADER_SIZE, old_flags);
+
+#ifndef SAFEMALLOC
+ /*
+ Trash memory if not safemalloc. We don't have to do this if safemalloc
+ is used as safemalloc will also do trashing
+ */
+ TRASH_FREE(ptr, old_size);
+#endif
+ sf_free(mh);
+ DBUG_VOID_RETURN;
+}
+
+
+void *my_memdup(PSI_memory_key key, const void *from, size_t length, myf my_flags)
+{
+ void *ptr;
+ DBUG_ENTER("my_memdup");
+
+ if ((ptr= my_malloc(key, length,my_flags)) != 0)
+ memcpy(ptr, from, length);
+ DBUG_RETURN(ptr);
+}
+
+
+char *my_strdup(PSI_memory_key key, const char *from, myf my_flags)
+{
+ char *ptr;
+ size_t length= strlen(from)+1;
+ DBUG_ENTER("my_strdup");
+
+ if ((ptr= (char*) my_malloc(key, length, my_flags)))
+ memcpy(ptr, from, length);
+ DBUG_RETURN(ptr);
+}
+
+
+char *my_strndup(PSI_memory_key key, const char *from, size_t length, myf my_flags)
+{
+ char *ptr;
+ DBUG_ENTER("my_strndup");
+
+ if ((ptr= (char*) my_malloc(key, length+1, my_flags)))
+ {
+ memcpy(ptr, from, length);
+ ptr[length]= 0;
+ }
+ DBUG_RETURN(ptr);
+}
+
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