Debugging Memory Heaps
Memory Management Functions
Managing Memory with Multiple Memory Heaps
Format
#include <umalloc.h> int _debug_uheapmin(Heap_t heap, const char *file, size_t line);
Language Level: Extension
_debug_uheapmin is the debug version of _uheapmin. Like _uheapmin, it returns all unused memory blocks from the specified heap to the operating system.
To return the memory, _debug_uheapmin calls the release_fn you supplied when you created the heap with _ucreate. If you do not supply a release_fn, _debug_uheapmin has no effect and returns 0.
In addition, _debug_uheapmin makes an implicit call to _uheap_check to validate the heap.
_debug_uheapmin works just like _debug_heapmin except that you specify the heap to use; _debug_heapmin always uses the default heap.
To use _debug_uheapmin, you must compile with the debug memory -qheapdebug compiler option. This option maps all _uheapmin calls to _debug_uheapmin.
Note: The -qheapdebug option maps all calls to memory management functions (including heap-specific versions) to their debug counterparts. To prevent a call from being mapped, parenthesize the function name.
Return Value
If successful, _debug_uheapmin returns
0. A nonzero return value indicates failure. If the heap
specified is not valid, _debug_uheapmin
generates an error message with the file name and line number
where the call to _debug_uheapmin was made.
Example
This example creates a heap and allocates memory from
it, then uses _debug_heapmin to release the
memory.
Note: You must compile this example with the -qheapdebug option to map the _uheapmin calls to _debug_uheapmin.
#include <stdlib.h> #include <stdio.h> #include <string.h> #include <umalloc.h>
int main(void)
{
Heap_t myheap;
char *ptr;
/* Use default heap as user heap */ myheap = _udefault(NULL);
/* Allocate a large object */
if (NULL == (ptr = (char*)_umalloc(myheap, 60000))) {
puts("Cannot allocate memory from user heap.\n");
exit(EXIT_FAILURE);
}
memset(ptr, 'x', 60000);
free(ptr);
/* _debug_uheapmin will attempt to return the freed object to the system */
if (0 != _uheapmin(myheap)) {
puts("_debug_uheapmin returns failed.\n");
exit(EXIT_FAILURE);
}
return 0;
}
Debugging Memory Heaps
Memory Management Functions
Managing Memory with Multiple
Memory Heaps
Debugging Problems with Heap
Memory
-qheapdebug Compiler
Option
_debug_calloc - Allocate and Initialize
Memory
_debug_free - Free Allocated Memory
_debug_heapmin - Free Unused Memory in the
Default Heap
_debug_malloc - Allocate Memory
_debug_memcpy - Copy Bytes
_debug_memmove - Copy Bytes
_debug_memset - Set Bytes to Value
_debug_realloc - Reallocate Memory Block
_debug_strcat - Concatenate Strings
_debug_strcpy - Copy Strings
_debug_strncat - Concatenate Strings
_debug_strncpy - Copy Strings
_debug_strnset - Set Characters in String
_debug_strset - Set Characters in String
_debug_ucalloc - Reserve and Initialize
Memory from User Heap
_debug_umalloc - Reserve Memory Block from
User Heap
