Wrapping malloc - C

Posted by Appu on Stack Overflow See other posts from Stack Overflow or by Appu
Published on 2010-03-19T18:29:27Z Indexed on 2010/03/19 18:31 UTC
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c

|

malloc

|

memory-management

I am a beginner in C. While reading git's source code, I found this wrapper function around malloc.

void *xmalloc(size_t size)
{
    void *ret = malloc(size);
    if (!ret && !size)
        ret = malloc(1);
    if (!ret) {
        release_pack_memory(size, -1);
        ret = malloc(size);
        if (!ret && !size)
            ret = malloc(1);
        if (!ret)
            die("Out of memory, malloc failed");
    }
#ifdef XMALLOC_POISON
    memset(ret, 0xA5, size);
#endif
    return ret;
}

Questions

I couldn't understand why are they using malloc(1)?
What does release_pack_memory does and I can't find this functions implementation in the whole source code.
What does the #ifdef XMALLOC_POISON memset(ret, 0xA5, size); does?

I am planning to reuse this function on my project. Is this a good wrapper around malloc?

Any help would be great.

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Developer IT

Wrapping malloc - C - Developer IT

Wrapping malloc - C

c

malloc

memory-management

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