Coverage Report

Created: 2023-09-23 07:04

/src/augeas/src/memory.c
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Source (jump to first uncovered line)
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/*
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 * memory.c: safer memory allocation
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 *
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 * Copyright (C) 2008-2016 Daniel P. Berrange
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 *
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 * This library is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * This library is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with this library; if not, write to the Free Software
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 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307  USA
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 *
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 */
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#include <config.h>
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#include <stdlib.h>
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#include <stddef.h>
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#include "memory.h"
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/* Return 1 if an array of N objects, each of size S, cannot exist due
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   to size arithmetic overflow.  S must be positive and N must be
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   nonnegative.  This is a macro, not an inline function, so that it
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   works correctly even when SIZE_MAX < N.
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   By gnulib convention, SIZE_MAX represents overflow in size
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   calculations, so the conservative dividend to use here is
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   SIZE_MAX - 1, since SIZE_MAX might represent an overflowed value.
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   However, malloc (SIZE_MAX) fails on all known hosts where
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   sizeof (ptrdiff_t) <= sizeof (size_t), so do not bother to test for
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   exactly-SIZE_MAX allocations on such hosts; this avoids a test and
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   branch when S is known to be 1.  */
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# define xalloc_oversized(n, s) \
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    ((size_t) (sizeof (ptrdiff_t) <= sizeof (size_t) ? -1 : -2) / (s) < (n))
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/**
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 * mem_alloc_n:
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 * @ptrptr: pointer to pointer for address of allocated memory
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 * @size: number of bytes to allocate
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 * @count: number of elements to allocate
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 *
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 * Allocate an array of memory 'count' elements long,
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 * each with 'size' bytes. Return the address of the
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 * allocated memory in 'ptrptr'.  The newly allocated
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 * memory is filled with zeros.
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 *
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 * Returns -1 on failure to allocate, zero on success
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 */
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int mem_alloc_n(void *ptrptr, size_t size, size_t count)
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11.2M
{
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11.2M
    if (AUGEAS_UNLIKELY(size == 0 || count == 0)) {
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        *(void **)ptrptr = NULL;
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        return 0;
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    }
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11.2M
    *(void**)ptrptr = calloc(count, size);
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11.2M
    if (AUGEAS_UNLIKELY(*(void**)ptrptr == NULL))
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0
        return -1;
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11.2M
    return 0;
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11.2M
}
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/**
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 * virReallocN:
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 * @ptrptr: pointer to pointer for address of allocated memory
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 * @size: number of bytes to allocate
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 * @count: number of elements in array
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 *
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 * Resize the block of memory in 'ptrptr' to be an array of
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 * 'count' elements, each 'size' bytes in length. Update 'ptrptr'
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 * with the address of the newly allocated memory. On failure,
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 * 'ptrptr' is not changed and still points to the original memory
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 * block. The newly allocated memory is filled with zeros.
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 *
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 * Returns -1 on failure to allocate, zero on success
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 */
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int mem_realloc_n(void *ptrptr, size_t size, size_t count)
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{
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    void *tmp;
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    if (AUGEAS_UNLIKELY(size == 0 || count == 0)) {
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0
        free(*(void **)ptrptr);
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0
        *(void **)ptrptr = NULL;
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        return 0;
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0
    }
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    if (AUGEAS_UNLIKELY(xalloc_oversized(count, size))) {
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0
        errno = ENOMEM;
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0
        return -1;
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0
    }
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    tmp = realloc(*(void**)ptrptr, size * count);
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    if (AUGEAS_UNLIKELY(!tmp))
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0
        return -1;
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    *(void**)ptrptr = tmp;
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    return 0;
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527k
}