/* lwext4 freestanding allocation shim for NTLite drivers. */

#include <stddef.h>
#include <stdint.h>
#include <string.h>
#include <ntlite/ddk/memory.h>

#include "ext4_port.h"

void* ext4_ntl_malloc(size_t size) {
    if (size == 0)
        size = 1;
    return MmAllocatePool(size);
}

void* ext4_ntl_calloc(size_t count, size_t size) {
    if (count != 0 && size > SIZE_MAX / count)
        return (void*)0;

    size_t bytes = count * size;
    if (bytes == 0)
        bytes = 1;

    void* ptr = MmAllocatePool(bytes);
    if (ptr)
        memset(ptr, 0, bytes);
    return ptr;
}

void* ext4_ntl_realloc(void* ptr, size_t size) {
    if (!ptr)
        return ext4_ntl_malloc(size);
    if (size == 0) {
        MmFreePool(ptr);
        return (void*)0;
    }
    return MmReallocatePool(ptr, size);
}

void ext4_ntl_free(void* ptr) {
    if (ptr)
        MmFreePool(ptr);
}

/* lwext4 uses the standard allocation names when CONFIG_USE_USER_MALLOC=0. */
void* malloc(size_t size) { return ext4_ntl_malloc(size); }
void* calloc(size_t count, size_t size) { return ext4_ntl_calloc(count, size); }
void* realloc(void* ptr, size_t size) { return ext4_ntl_realloc(ptr, size); }
void free(void* ptr) { ext4_ntl_free(ptr); }
/* lwext4 uses qsort for directory-index construction.  A small insertion
 * sort is sufficient here and keeps the freestanding port dependency-free. */
void qsort(void* base, size_t count, size_t size,
           int (*compare)(const void*, const void*)) {
    if (!base || !compare || size == 0 || count < 2)
        return;

    unsigned char* bytes = (unsigned char*)base;
    for (size_t i = 1; i < count; ++i) {
        size_t j = i;
        while (j != 0) {
            unsigned char* left = bytes + (j - 1) * size;
            unsigned char* right = bytes + j * size;
            if (compare(left, right) <= 0)
                break;

            for (size_t k = 0; k < size; ++k) {
                unsigned char temp = left[k];
                left[k] = right[k];
                right[k] = temp;
            }
            --j;
        }
    }
}