nasm/nasmlib/malloc.c
H. Peter Anvin (Intel) 3b91f4c117 malloc: handle potential infinite loop in nasm_alloc_failed()
It is possible on memory exhaustion that nasm_fatal() might cause
another allocation error, thus calling nasm_alloc_failed() again. If
we find us in nasm_alloc_failed() for a second time, try to get a
message out and then call abort().

Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com>
2018-12-13 13:55:25 -08:00

180 lines
4.5 KiB
C

/* ----------------------------------------------------------------------- *
*
* Copyright 1996-2018 The NASM Authors - All Rights Reserved
* See the file AUTHORS included with the NASM distribution for
* the specific copyright holders.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following
* conditions are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* ----------------------------------------------------------------------- */
/*
* nasmlib.c library routines for the Netwide Assembler
*/
#include "compiler.h"
#include <stdlib.h>
#include "nasmlib.h"
#include "error.h"
static no_return nasm_alloc_failed(void)
{
/* If nasm_fatal() gets us back here, then croak hard */
static bool already_here = false;
FILE *errfile;
if (likely(!already_here)) {
already_here = true;
nasm_fatal(0, "out of memory!");
}
errfile = error_file;
if (!errfile)
error_file = stderr;
fprintf(error_file, "nasm: out of memory!\n");
fflush(error_file);
fflush(NULL);
abort();
}
static inline void *validate_ptr(void *p)
{
if (unlikely(!p))
nasm_alloc_failed();
return p;
}
void *nasm_malloc(size_t size)
{
return validate_ptr(malloc(size));
}
void *nasm_calloc(size_t size, size_t nelem)
{
return validate_ptr(calloc(size, nelem));
}
void *nasm_zalloc(size_t size)
{
return validate_ptr(calloc(1, size));
}
void *nasm_realloc(void *q, size_t size)
{
return validate_ptr(q ? realloc(q, size) : malloc(size));
}
void nasm_free(void *q)
{
if (q)
free(q);
}
char *nasm_strdup(const char *s)
{
char *p;
size_t size = strlen(s) + 1;
p = nasm_malloc(size);
return memcpy(p, s, size);
}
char *nasm_strndup(const char *s, size_t len)
{
char *p;
len = strnlen(s, len);
p = nasm_malloc(len+1);
p[len] = '\0';
return memcpy(p, s, len);
}
char *nasm_strcat(const char *one, const char *two)
{
char *rslt;
size_t l1 = strlen(one);
size_t l2 = strlen(two);
rslt = nasm_malloc(l1 + l2 + 1);
memcpy(rslt, one, l1);
memcpy(rslt + l1, two, l2+1);
return rslt;
}
char *nasm_strcatn(const char *str1, ...)
{
va_list ap;
char *rslt; /* Output buffer */
size_t s; /* Total buffer size */
size_t n; /* Number of arguments */
size_t *ltbl; /* Table of lengths */
size_t l, *lp; /* Length for current argument */
const char *p; /* Currently examined argument */
char *q; /* Output pointer */
n = 0; /* No strings encountered yet */
p = str1;
va_start(ap, str1);
while (p) {
n++;
p = va_arg(ap, const char *);
}
va_end(ap);
ltbl = nasm_malloc(n * sizeof(size_t));
s = 1; /* Space for final NULL */
p = str1;
lp = ltbl;
va_start(ap, str1);
while (p) {
*lp++ = l = strlen(p);
s += l;
p = va_arg(ap, const char *);
}
va_end(ap);
q = rslt = nasm_malloc(s);
p = str1;
lp = ltbl;
va_start(ap, str1);
while (p) {
l = *lp++;
memcpy(q, p, l);
q += l;
p = va_arg(ap, const char *);
}
va_end(ap);
*q = '\0';
nasm_free(ltbl);
return rslt;
}