C++
#include "zmemory.h"
class Foo
{
};
int main()
{
ZFILENAME("main.txt");
// ----------------------------
// Was: Foo *fooPtr = new Foo();
// ----------------------------
Foo *fooPtr = ZNEW(Foo());
// ----------------------------
// Was: int *ptr = new int[5];
// ----------------------------
int *ptr = ZNEW(int[5]);
// ----------------------------
// Was: delete fooPtr;
// ----------------------------
ZDELETE(fooPtr);
// ----------------------------
// Was: delete[] fooPtr;
// ----------------------------
ZDELETE_ARRAY(ptr);
return(0);
}
|
C
#include "zmemory.h"
int main()
{
char *s1;
char *s2;
char *s3;
ZFILENAME("main.txt");
s1 = (char *)ZMALLOC(10 * sizeof(char));
s2 = (char *)ZCALLOC(5, sizeof(char));
s3 = (char *)ZMALLOC(10 * sizeof(char));
ZFREE(s1);
ZFREE(s2);
s3 = ZREALLOC(s3, 1000000 * sizeof(char));
ZFREE(s3);
return(0);
}
|
After you've swapped out malloc for ZMALLOC (or new for ZNEW, etc.)
throughout your code, recompile and run your program (be sure to
use ZFILENAME to set the output filename).
Your output file will look something like this ...
0x804a050 malloc main.c 12
0x804a060 calloc main.c 13
0x804a070 malloc main.c 14
0x804a050 free main.c 16
0x804a060 free main.c 17
0x804a070 refree main.c 19
0xb7cf8008 realloc main.c 19
0xb7cf8008 free main.c 21
Sort the output, the 'sort' command line utility on windows
will do the job (unix based systems have a similar utility)
C:\>sort output.txt > sorted.txt
Here are the contents of 'sorted.txt' ...
0x804a050 free main.c 16
0x804a050 malloc main.c 12
0x804a060 calloc main.c 13
0x804a060 free main.c 17
0x804a070 malloc main.c 14
0x804a070 refree main.c 19
0xb7cf8008 free main.c 21
0xb7cf8008 realloc main.c 19
Notice that every address appears an even number of times
(one free for each malloc, etc.). This is the pattern
you'll see when the program in question doesn't leak memory.
On the other hand, if you find an address from an allocation
that's not matched by a deallocation, you've found a memory
leak (sorting the output makes these easy to spot).
This assumes you convrted all the memory allocation/deallocation
calls in your program to use the Z macros, if you missed any,
you can have false positives or false negatives).
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