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commit bash-20200527 snapshot

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This commit is contained in:
Chet Ramey
2020-05-29 14:29:34 -04:00
parent ce1a3c07c4
commit 37adc8b99d
23 changed files with 443 additions and 601 deletions
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lib/malloc/malloc.c
+75 -20
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@@ -1,6 +1,6 @@
/* malloc.c - dynamic memory allocation for bash. */
/* Copyright (C) 1985-2005 Free Software Foundation, Inc.
/* Copyright (C) 1985-2020 Free Software Foundation, Inc.
This file is part of GNU Bash, the Bourne-Again SHell.
@@ -25,6 +25,8 @@
*
* Nov 1983, Mike@BRL, Added support for 4.1C/4.2 BSD.
*
* [VERY] old explanation:
*
* This is a very fast storage allocator. It allocates blocks of a small
* number of different sizes, and keeps free lists of each size. Blocks
* that don't exactly fit are passed up to the next larger size. In this
@@ -138,22 +140,35 @@
enough room in the block for the new size. Range checking is always
done. */
union mhead {
#if SIZEOF_CHAR_P == 8
bits64_t mh_align[2]; /* 16 */
#else
bits64_t mh_align; /* 8 */
#endif
struct {
char mi_alloc; /* ISALLOC or ISFREE */ /* 1 */
char mi_index; /* index in nextf[] */ /* 1 */
/* Remainder are valid only when block is allocated */
u_bits16_t mi_magic2; /* should be == MAGIC2 */ /* 2 */
u_bits32_t mi_nbytes; /* # of bytes allocated */ /* 4 */
#if SIZEOF_CHAR_P == 8
char mi_magic8[8]; /* MAGIC1 guard bytes */ /* 8 */
#endif
} minfo;
};
#define mh_alloc minfo.mi_alloc
#define mh_index minfo.mi_index
#define mh_nbytes minfo.mi_nbytes
#define mh_magic2 minfo.mi_magic2
#define mh_magic8 minfo.mi_magic8
#define MOVERHEAD sizeof(union mhead)
#if SIZEOF_CHAR_P == 8
#define MALIGN_MASK 15
#else
#define MALIGN_MASK 7 /* one less than desired alignment */
#endif
typedef union _malloc_guard {
char s[4];
@@ -167,6 +182,8 @@ typedef union _malloc_guard {
to describe the overhead for when the block is in use,
and we do not want the free-list pointer to count in that. */
/* If SIZEOF_CHAR_P == 8, this goes into the mh_magic8 buffer at the end of
the rest of the struct. This may need adjusting. */
#define CHAIN(a) \
(*(union mhead **) (sizeof (char *) + (char *) (a)))
@@ -174,13 +191,14 @@ typedef union _malloc_guard {
and end of each allocated block, and make sure they are undisturbed
whenever a free or a realloc occurs. */
/* Written in the 2 bytes before the block's real space (-4 bytes) */
/* Written in the bytes before the block's real space (-SIZEOF_CHAR_P bytes) */
#define MAGIC1 0x55
#define MAGIC2 0x5555
#define MSLOP 4 /* 4 bytes extra for u_bits32_t size */
/* How many bytes are actually allocated for a request of size N --
rounded up to nearest multiple of 8 after accounting for malloc
overhead. */
rounded up to nearest multiple of 2*SIZEOF_CHAR_P after accounting for
malloc overhead. */
#define ALLOCATED_BYTES(n) \
(((n) + MOVERHEAD + MSLOP + MALIGN_MASK) & ~MALIGN_MASK)
@@ -277,24 +295,24 @@ extern int errno;
#endif
/* Declarations for internal functions */
static PTR_T internal_malloc __P((size_t, const char *, int, int));
static PTR_T internal_realloc __P((PTR_T, size_t, const char *, int, int));
static void internal_free __P((PTR_T, const char *, int, int));
static PTR_T internal_memalign __P((size_t, size_t, const char *, int, int));
static PTR_T internal_malloc PARAMS((size_t, const char *, int, int));
static PTR_T internal_realloc PARAMS((PTR_T, size_t, const char *, int, int));
static void internal_free PARAMS((PTR_T, const char *, int, int));
static PTR_T internal_memalign PARAMS((size_t, size_t, const char *, int, int));
#ifndef NO_CALLOC
static PTR_T internal_calloc __P((size_t, size_t, const char *, int, int));
static void internal_cfree __P((PTR_T, const char *, int, int));
static PTR_T internal_calloc PARAMS((size_t, size_t, const char *, int, int));
static void internal_cfree PARAMS((PTR_T, const char *, int, int));
#endif
#ifndef NO_VALLOC
static PTR_T internal_valloc __P((size_t, const char *, int, int));
static PTR_T internal_valloc PARAMS((size_t, const char *, int, int));
#endif
#if defined (botch)
extern void botch ();
#else
static void botch __P((const char *, const char *, int));
static void botch PARAMS((const char *, const char *, int));
#endif
static void xbotch __P((PTR_T, int, const char *, const char *, int));
static void xbotch PARAMS((PTR_T, int, const char *, const char *, int));
#if !HAVE_DECL_SBRK
extern char *sbrk ();
@@ -302,7 +320,7 @@ extern char *sbrk ();
#ifdef SHELL
extern int interrupt_immediately, running_trap;
extern int signal_is_trapped __P((int));
extern int signal_is_trapped PARAMS((int));
#endif
#ifdef MALLOC_STATS
@@ -321,8 +339,8 @@ int malloc_mmap_threshold = MMAP_THRESHOLD;
char _malloc_trace_buckets[NBUCKETS];
/* These should really go into a header file. */
extern void mtrace_alloc __P((const char *, PTR_T, size_t, const char *, int));
extern void mtrace_free __P((PTR_T, int, const char *, int));
extern void mtrace_alloc PARAMS((const char *, PTR_T, size_t, const char *, int));
extern void mtrace_free PARAMS((PTR_T, int, const char *, int));
#endif
#if !defined (botch)
@@ -693,7 +711,7 @@ morecore (nu)
memtop += sbrk_amt;
/* shouldn't happen, but just in case -- require 8-byte alignment */
/* shouldn't happen, but just in case -- require 8- or 16-byte alignment */
if ((long)mp & MALIGN_MASK)
{
mp = (union mhead *) (((long)mp + MALIGN_MASK) & ~MALIGN_MASK);
@@ -723,8 +741,13 @@ malloc_debug_dummy ()
write (1, "malloc_debug_dummy\n", 19);
}
#if SIZEOF_CHAR_P == 8
#define PREPOP_BIN 3
#define PREPOP_SIZE 64
#else
#define PREPOP_BIN 2
#define PREPOP_SIZE 32
#endif
static int
pagealign ()
@@ -760,8 +783,8 @@ pagealign ()
memtop += sbrk_needed;
/* Take the memory which would otherwise be wasted and populate the most
popular bin (2 == 32 bytes) with it. Add whatever we need to curbrk
to make things 32-byte aligned, compute how many 32-byte chunks we're
popular bin (3 == 64 bytes) with it. Add whatever we need to curbrk
to make things 64-byte aligned, compute how many 64-byte chunks we're
going to get, and set up the bin. */
curbrk += sbrk_needed & (PREPOP_SIZE - 1);
sbrk_needed -= sbrk_needed & (PREPOP_SIZE - 1);
@@ -822,7 +845,7 @@ internal_malloc (n, file, line, flags) /* get a block */
if (nbytes <= binsize(nunits))
break;
/* Silently reject too-large requests. */
/* Silently reject too-large requests. XXX - can increase this if HAVE_MMAP */
if (nunits >= NBUCKETS)
return ((PTR_T) NULL);
@@ -863,6 +886,11 @@ internal_malloc (n, file, line, flags) /* get a block */
p->mh_magic2 = MAGIC2;
p->mh_nbytes = n;
#if SIZEOF_CHAR_P == 8
/* Begin guard */
MALLOC_MEMSET ((char *)p->mh_magic8, MAGIC1, 8);
#endif
/* End guard */
mg.i = n;
z = mg.s;
@@ -897,6 +925,14 @@ internal_malloc (n, file, line, flags) /* get a block */
_malloc_ckwatch (p + 1, file, line, W_ALLOC, n);
#endif
#if defined (MALLOC_DEBUG)
z = (char *) (p + 1);
/* Check alignment of returned pointer */
if ((unsigned long)z & MALIGN_MASK)
fprintf (stderr, "malloc: %s:%d: warning: request for %ld bytes not aligned on %d byte boundary\r\n",
file ? file : _("unknown"), line, p->mh_nbytes, MALIGN_MASK+1);
#endif
return (PTR_T) (p + 1);
}
@@ -956,6 +992,15 @@ internal_free (mem, file, line, flags)
if (IN_BUCKET(nbytes, nunits) == 0)
xbotch (mem, ERR_UNDERFLOW,
_("free: underflow detected; mh_nbytes out of range"), file, line);
#if SIZEOF_CHAR_P == 8
{
int i;
for (i = 0, z = p->mh_magic8; i < 8; i++)
if (*z++ != MAGIC1)
xbotch (mem, ERR_UNDERFLOW,
_("free: underflow detected; magic8 corrupted"), file, line);
}
#endif
ap += p->mh_nbytes;
z = mg.s;
@@ -1087,6 +1132,16 @@ internal_realloc (mem, n, file, line, flags)
if (IN_BUCKET(nbytes, nunits) == 0)
xbotch (mem, ERR_UNDERFLOW,
_("realloc: underflow detected; mh_nbytes out of range"), file, line);
#if SIZEOF_CHAR_P == 8
{
int i;
for (i = 0, z = p->mh_magic8; i < 8; i++)
if (*z++ != MAGIC1)
xbotch (mem, ERR_UNDERFLOW,
_("realloc: underflow detected; magic8 corrupted"), file, line);
}
#endif
m = (char *)mem + (tocopy = p->mh_nbytes);
z = mg.s;