-/*
- * Copyright (c) 1983 Regents of the University of California.
- * All rights reserved. The Berkeley software License Agreement
- * specifies the terms and conditions for redistribution.
+/*-
+ * Copyright (c) 1983, 1991 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * %sccs.include.redist.c%
*/
#ifndef lint
-/* From "@(#)malloc.c 5.5 (Berkeley) 2/25/86"; */
-static char *sccsid = "@(#)alloc.c 5.4 (Berkeley) %G%";
-#endif not lint
+static char sccsid[] = "@(#)alloc.c 5.11 (Berkeley) %G%";
+#endif /* not lint */
/*
- * malloc.c (Caltech) 2/21/82
+ * tc.alloc.c from malloc.c (Caltech) 2/21/82
* Chris Kingsley, kingsley@cit-20.
*
- * This is a very fast storage allocator. It allocates blocks of a small
+ * 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
- * implementation, the available sizes are 2^n-4 (or 2^n-10) bytes long.
- * This is designed for use in a virtual memory environment.
+ * don't exactly fit are passed up to the next larger size. In this
+ * implementation, the available sizes are 2^n-4 (or 2^n-12) bytes long.
+ * This is designed for use in a program that uses vast quantities of memory,
+ * but bombs when it runs out.
*/
#include <sys/types.h>
+#include <unistd.h>
+#include <string.h>
+#if __STDC__
+# include <stdarg.h>
+#else
+# include <varargs.h>
+#endif
+
+#include "csh.h"
+#include "extern.h"
+
+char *memtop = NULL; /* PWP: top of current memory */
+char *membot = NULL; /* PWP: bottom of allocatable memory */
+
+#ifndef SYSMALLOC
+#undef RCHECK
+#undef DEBUG
+
+
+#ifndef NULL
#define NULL 0
+#endif
+
/*
* The overhead on a block is at least 4 bytes. When free, this space
* contains a pointer to the next free block, and the bottom two bits must
* be zero. When in use, the first byte is set to MAGIC, and the second
* byte is the size index. The remaining bytes are for alignment.
- * If range checking is enabled then a second word holds the size of the
- * requested block, less 1, rounded up to a multiple of sizeof(RMAGIC).
- * The order of elements is critical: ov_magic must overlay the low order
- * bits of ov_next, and ov_magic can not be a valid ov_next bit pattern.
+ * If range checking is enabled and the size of the block fits
+ * in two bytes, then the top two bytes hold the size of the requested block
+ * plus the range checking words, and the header word MINUS ONE.
*/
-union overhead {
- union overhead *ov_next; /* when free */
- struct {
- u_char ovu_magic; /* magic number */
- u_char ovu_index; /* bucket # */
+
+#define ROUNDUP 7
+
+#define ALIGN(a) (((a) + ROUNDUP) & ~ROUNDUP)
+
+union overhead {
+ union overhead *ov_next; /* when free */
+ struct {
+ u_char ovu_magic; /* magic number */
+ u_char ovu_index; /* bucket # */
#ifdef RCHECK
- u_short ovu_rmagic; /* range magic number */
- u_int ovu_size; /* actual block size */
+ u_short ovu_size; /* actual block size */
+ u_int ovu_rmagic; /* range magic number */
#endif
- } ovu;
+ } ovu;
#define ov_magic ovu.ovu_magic
#define ov_index ovu.ovu_index
-#define ov_rmagic ovu.ovu_rmagic
#define ov_size ovu.ovu_size
+#define ov_rmagic ovu.ovu_rmagic
};
-#define MAGIC 0xef /* magic # on accounting info */
-#define RMAGIC 0x5555 /* magic # on range info */
-
+#define MAGIC 0xfd /* magic # on accounting info */
+#define RMAGIC 0x55555555 /* magic # on range info */
#ifdef RCHECK
-#define RSLOP sizeof (u_short)
+#define RSLOP sizeof (u_int)
#else
#define RSLOP 0
#endif
* precedes the data area returned to the user.
*/
#define NBUCKETS 30
-static union overhead *nextf[NBUCKETS];
-extern char *sbrk();
+static union overhead *nextf[NBUCKETS];
-static int pagesz; /* page size */
-static int pagebucket; /* page size bucket */
+static int findbucket __P((union overhead *, int));
+static void morecore __P((int));
/*
* nmalloc[i] is the difference between the number of mallocs and frees
* for a given block size.
*/
-static u_int nmalloc[NBUCKETS];
+static u_int nmalloc[NBUCKETS];
-#if defined(DEBUG) || defined(RCHECK)
-#define ASSERT(p) if (!(p)) botch("p")
-static
-botch(s)
- char *s;
-{
- printf("\r\nassertion botched: %s\r\n", s);
- abort();
-}
+
+#ifdef DEBUG
+#define CHECK(a, str, p) \
+ if (a) { \
+ (void) fprintfcsherr, (str, p); \
+ (void) fprintf(csherr, "memtop = %lx membot = %lx.\n", memtop, membot);\
+ abort(); \
+ } \
+ else
#else
-#define ASSERT(p)
+#define CHECK(a, str, p) \
+ if (a) { \
+ (void) fprintf(csherr, str, p); \
+ (void) fprintf(csherr, "memtop = %lx membot = %lx.\n", memtop, membot);\
+ return; \
+ } \
+ else
#endif
-char *
+ptr_t
malloc(nbytes)
- unsigned nbytes;
+ register size_t nbytes;
{
- register union overhead *op;
- register int bucket;
- register unsigned amt, n;
+#ifndef lint
+ register union overhead *p;
+ register int bucket = 0;
+ register unsigned shiftr;
- /*
- * First time malloc is called, setup page size and
- * align break pointer so all data will be page aligned.
- */
- if (pagesz == 0) {
- pagesz = n = getpagesize();
- op = (union overhead *)sbrk(0);
- n = n - sizeof (*op) - ((int)op & (n - 1));
- if (n < 0)
- n += pagesz;
- if (n) {
- if (sbrk(n) == (char *)-1)
- return (NULL);
- }
- bucket = 0;
- amt = 8;
- while (pagesz > amt) {
- amt <<= 1;
- bucket++;
- }
- pagebucket = bucket;
- }
- /*
- * Convert amount of memory requested into closest block size
- * stored in hash buckets which satisfies request.
- * Account for space used per block for accounting.
- */
- if (nbytes <= (n = pagesz - sizeof (*op) - RSLOP)) {
-#ifndef RCHECK
- amt = 8; /* size of first bucket */
- bucket = 0;
+ /*
+ * Convert amount of memory requested into closest block size stored in
+ * hash buckets which satisfies request. Account for space used per block
+ * for accounting.
+ */
+ nbytes = ALIGN(ALIGN(sizeof(union overhead)) + nbytes + RSLOP);
+ shiftr = (nbytes - 1) >> 2;
+
+ /* apart from this loop, this is O(1) */
+ while (shiftr >>= 1)
+ bucket++;
+ /*
+ * If nothing in hash bucket right now, request more memory from the
+ * system.
+ */
+ if (nextf[bucket] == NULL)
+ morecore(bucket);
+ if ((p = (union overhead *) nextf[bucket]) == NULL) {
+ child++;
+#ifndef DEBUG
+ stderror(ERR_NOMEM);
#else
- amt = 16; /* size of first bucket */
- bucket = 1;
+ showall();
+ (void) fprintf(csherr, "nbytes=%d: Out of memory\n", nbytes);
+ abort();
#endif
- n = -(sizeof (*op) + RSLOP);
- } else {
- amt = pagesz;
- bucket = pagebucket;
- }
- while (nbytes > amt + n) {
- amt <<= 1;
- if (amt == 0)
- return (NULL);
- bucket++;
- }
- /*
- * If nothing in hash bucket right now,
- * request more memory from the system.
- */
- if ((op = nextf[bucket]) == NULL) {
- morecore(bucket);
- if ((op = nextf[bucket]) == NULL)
- return (NULL);
- }
- /* remove from linked list */
- nextf[bucket] = op->ov_next;
- op->ov_magic = MAGIC;
- op->ov_index = bucket;
- nmalloc[bucket]++;
+ /* fool lint */
+ return ((ptr_t) 0);
+ }
+ /* remove from linked list */
+ nextf[bucket] = nextf[bucket]->ov_next;
+ p->ov_magic = MAGIC;
+ p->ov_index = bucket;
+ nmalloc[bucket]++;
#ifdef RCHECK
- /*
- * Record allocated size of block and
- * bound space with magic numbers.
- */
- op->ov_size = (nbytes + RSLOP - 1) & ~(RSLOP - 1);
- op->ov_rmagic = RMAGIC;
- *(u_short *)((caddr_t)(op + 1) + op->ov_size) = RMAGIC;
+ /*
+ * Record allocated size of block and bound space with magic numbers.
+ */
+ if (nbytes <= 0x10000)
+ p->ov_size = nbytes - 1;
+ p->ov_rmagic = RMAGIC;
+ *((u_int *) (((caddr_t) p) + nbytes - RSLOP)) = RMAGIC;
#endif
- return ((char *)(op + 1));
+ return ((ptr_t) (((caddr_t) p) + ALIGN(sizeof(union overhead))));
+#else
+ if (nbytes)
+ return ((ptr_t) 0);
+ else
+ return ((ptr_t) 0);
+#endif /* !lint */
}
+#ifndef lint
/*
* Allocate more memory to the indicated bucket.
*/
+static void
morecore(bucket)
- int bucket;
+ register int bucket;
{
- register union overhead *op;
- register int sz; /* size of desired block */
- int amt; /* amount to allocate */
- int nblks; /* how many blocks we get */
+ register union overhead *op;
+ register int rnu; /* 2^rnu bytes will be requested */
+ register int nblks; /* become nblks blocks of the desired size */
+ register int siz;
- /*
- * sbrk_size <= 0 only for big, FLUFFY, requests (about
- * 2^30 bytes on a VAX, I think) or for a negative arg.
- */
- sz = 1 << (bucket + 3);
-#ifdef DEBUG
- ASSERT(sz > 0);
-#else
- if (sz <= 0)
- return;
-#endif
- if (sz < pagesz) {
- amt = pagesz;
- nblks = amt / sz;
- } else {
- amt = sz + pagesz;
- nblks = 1;
- }
- op = (union overhead *)sbrk(amt);
- /* no more room! */
- if ((int)op == -1)
- return;
- /*
- * Add new memory allocated to that on
- * free list for this hash bucket.
- */
- nextf[bucket] = op;
- while (--nblks > 0) {
- op->ov_next = (union overhead *)((caddr_t)op + sz);
- op = (union overhead *)((caddr_t)op + sz);
- }
+ if (nextf[bucket])
+ return;
+ /*
+ * Insure memory is allocated on a page boundary. Should make getpageize
+ * call?
+ */
+ op = (union overhead *) sbrk(0);
+ memtop = (char *) op;
+ if (membot == NULL)
+ membot = memtop;
+ if ((int) op & 0x3ff) {
+ memtop = (char *) sbrk(1024 - ((int) op & 0x3ff));
+ memtop += 1024 - ((int) op & 0x3ff);
+ }
+
+ /* take 2k unless the block is bigger than that */
+ rnu = (bucket <= 8) ? 11 : bucket + 3;
+ nblks = 1 << (rnu - (bucket + 3)); /* how many blocks to get */
+ memtop = (char *) sbrk(1 << rnu); /* PWP */
+ op = (union overhead *) memtop;
+ memtop += 1 << rnu;
+ /* no more room! */
+ if ((int) op == -1)
+ return;
+ /*
+ * Round up to minimum allocation size boundary and deduct from block count
+ * to reflect.
+ */
+ if (((u_int) op) & ROUNDUP) {
+ op = (union overhead *) (((u_int) op + (ROUNDUP + 1)) & ~ROUNDUP);
+ nblks--;
+ }
+ /*
+ * Add new memory allocated to that on free list for this hash bucket.
+ */
+ nextf[bucket] = op;
+ siz = 1 << (bucket + 3);
+ while (--nblks > 0) {
+ op->ov_next = (union overhead *) (((caddr_t) op) + siz);
+ op = (union overhead *) (((caddr_t) op) + siz);
+ }
+ op->ov_next = NULL;
}
+#endif
+
+void
free(cp)
- char *cp;
-{
- register int size;
- register union overhead *op;
-
- if (cp == NULL)
- return;
- op = (union overhead *)((caddr_t)cp - sizeof (union overhead));
- /*
- * The following botch is because csh tries to free a free block
- * when processing the =~ or !~ operators. -- layer@ucbmonet
- */
-#ifdef CSHbotch /* was DEBUG */
- ASSERT(op->ov_magic == MAGIC); /* make sure it was in use */
+ ptr_t cp;
+{
+#ifndef lint
+ register int size;
+ register union overhead *op;
+
+ if (cp == NULL)
+ return;
+ CHECK(!memtop || !membot, "free(%lx) called before any allocations.", cp);
+ CHECK(cp > (ptr_t) memtop, "free(%lx) above top of memory.", cp);
+ CHECK(cp < (ptr_t) membot, "free(%lx) above top of memory.", cp);
+ op = (union overhead *) (((caddr_t) cp) - ALIGN(sizeof(union overhead)));
+ CHECK(op->ov_magic != MAGIC, "free(%lx) bad block.", cp);
+
+#ifdef RCHECK
+ if (op->ov_index <= 13)
+ CHECK(*(u_int *) ((caddr_t) op + op->ov_size + 1 - RSLOP) != RMAGIC,
+ "free(%lx) bad range check.", cp);
+#endif
+ CHECK(op->ov_index >= NBUCKETS, "free(%lx) bad block index.", cp);
+ size = op->ov_index;
+ op->ov_next = nextf[size];
+ nextf[size] = op;
+
+ nmalloc[size]--;
+
#else
- if (op->ov_magic != MAGIC)
- return; /* sanity */
+ if (cp == NULL)
+ return;
#endif
-#ifdef RCHECK
- ASSERT(op->ov_rmagic == RMAGIC);
- ASSERT(*(u_short *)((caddr_t)(op + 1) + op->ov_size) == RMAGIC);
+}
+
+ptr_t
+calloc(i, j)
+ size_t i, j;
+{
+#ifndef lint
+ register char *cp, *scp;
+
+ i *= j;
+ scp = cp = (char *) xmalloc((size_t) i);
+ if (i != 0)
+ do
+ *cp++ = 0;
+ while (--i);
+
+ return (scp);
+#else
+ if (i && j)
+ return ((ptr_t) 0);
+ else
+ return ((ptr_t) 0);
#endif
- size = op->ov_index;
- ASSERT(size < NBUCKETS);
- op->ov_next = nextf[size]; /* also clobbers ov_magic */
- nextf[size] = op;
- nmalloc[size]--;
}
/*
* is extern so the caller can modify it). If that fails we just copy
* however many bytes was given to realloc() and hope it's not huge.
*/
-int realloc_srchlen = 4; /* 4 should be plenty, -1 =>'s whole list */
+#ifndef lint
+int realloc_srchlen = 4; /* 4 should be plenty, -1 =>'s whole list */
-char *
+#endif /* lint */
+
+ptr_t
realloc(cp, nbytes)
- char *cp;
- unsigned nbytes;
-{
- register u_int onb, i;
- union overhead *op;
- char *res;
- int was_alloced = 0;
- static int findbucket();
-
- if (cp == NULL)
- return (malloc(nbytes));
- op = (union overhead *)((caddr_t)cp - sizeof (union overhead));
- if (op->ov_magic == MAGIC) {
- was_alloced++;
- i = op->ov_index;
- } else {
- /*
- * Already free, doing "compaction".
- *
- * Search for the old block of memory on the
- * free list. First, check the most common
- * case (last element free'd), then (this failing)
- * the last ``realloc_srchlen'' items free'd.
- * If all lookups fail, then assume the size of
- * the memory block being realloc'd is the
- * largest possible (so that all "nbytes" of new
- * memory are copied into). Note that this could cause
- * a memory fault if the old area was tiny, and the moon
- * is gibbous. However, that is very unlikely.
- */
- if ((i = findbucket(op, 1)) < 0 &&
- (i = findbucket(op, realloc_srchlen)) < 0)
- i = NBUCKETS;
- }
- onb = 1 << (i + 3);
- if (onb < pagesz)
- onb -= sizeof (*op) + RSLOP;
- else
- onb += pagesz - sizeof (*op) - RSLOP;
- /* avoid the copy if same size block */
- if (was_alloced) {
- if (i) {
- i = 1 << (i + 2);
- if (i < pagesz)
- i -= sizeof (*op) + RSLOP;
- else
- i += pagesz - sizeof (*op) - RSLOP;
- }
- if (nbytes <= onb && nbytes > i) {
-#ifdef RCHECK
- op->ov_size = (nbytes + RSLOP - 1) & ~(RSLOP - 1);
- *(u_short *)((caddr_t)(op + 1) + op->ov_size) = RMAGIC;
-#endif
- return(cp);
- } else
- free(cp);
- }
- if ((res = malloc(nbytes)) == NULL)
- return (NULL);
- if (cp != res) /* common optimization if "compacting" */
- bcopy(cp, res, (nbytes < onb) ? nbytes : onb);
- return (res);
+ ptr_t cp;
+ size_t nbytes;
+{
+#ifndef lint
+ register u_int onb;
+ union overhead *op;
+ char *res;
+ register int i;
+ int was_alloced = 0;
+
+ if (cp == NULL)
+ return (malloc(nbytes));
+ op = (union overhead *) (((caddr_t) cp) - ALIGN(sizeof(union overhead)));
+ if (op->ov_magic == MAGIC) {
+ was_alloced++;
+ i = op->ov_index;
+ }
+ else
+ /*
+ * Already free, doing "compaction".
+ *
+ * Search for the old block of memory on the free list. First, check the
+ * most common case (last element free'd), then (this failing) the last
+ * ``realloc_srchlen'' items free'd. If all lookups fail, then assume
+ * the size of the memory block being realloc'd is the smallest
+ * possible.
+ */
+ if ((i = findbucket(op, 1)) < 0 &&
+ (i = findbucket(op, realloc_srchlen)) < 0)
+ i = 0;
+
+ onb = ALIGN(nbytes + ALIGN(sizeof(union overhead)) + RSLOP);
+
+ /* avoid the copy if same size block */
+ if (was_alloced && (onb < (1 << (i + 3))) && (onb >= (1 << (i + 2))))
+ return ((ptr_t) cp);
+ if ((res = malloc(nbytes)) == NULL)
+ return ((ptr_t) 0);
+ if (cp != res) /* common optimization */
+ bcopy(cp, res, nbytes);
+ if (was_alloced)
+ free(cp);
+ return (res);
+#else
+ if (cp && nbytes)
+ return ((ptr_t) 0);
+ else
+ return ((ptr_t) 0);
+#endif /* !lint */
}
+
+
+#ifndef lint
/*
* Search ``srchlen'' elements of each free list for a block whose
* header starts at ``freep''. If srchlen is -1 search the whole list.
* Return bucket number, or -1 if not found.
*/
-static
+static int
findbucket(freep, srchlen)
- union overhead *freep;
- int srchlen;
+ union overhead *freep;
+ int srchlen;
{
- register union overhead *p;
- register int i, j;
-
- for (i = 0; i < NBUCKETS; i++) {
- j = 0;
- for (p = nextf[i]; p && j != srchlen; p = p->ov_next) {
- if (p == freep)
- return (i);
- j++;
- }
+ register union overhead *p;
+ register int i, j;
+
+ for (i = 0; i < NBUCKETS; i++) {
+ j = 0;
+ for (p = nextf[i]; p && j != srchlen; p = p->ov_next) {
+ if (p == freep)
+ return (i);
+ j++;
}
- return (-1);
+ }
+ return (-1);
}
+#endif
+
+
+#else /* SYSMALLOC */
+
+/**
+ ** ``Protected versions'' of malloc, realloc, calloc, and free
+ **
+ ** On many systems:
+ **
+ ** 1. malloc(0) is bad
+ ** 2. free(0) is bad
+ ** 3. realloc(0, n) is bad
+ ** 4. realloc(n, 0) is bad
+ **
+ ** Also we call our error routine if we run out of memory.
+ **/
+char *
+Malloc(n)
+ size_t n;
+{
+ ptr_t ptr;
+
+ n = n ? n : 1;
+
+ if ((ptr = malloc(n)) == (ptr_t) 0) {
+ child++;
+ stderror(ERR_NOMEM);
+ }
+ return ((char *) ptr);
+}
+
+char *
+Realloc(p, n)
+ ptr_t p;
+ size_t n;
+{
+ ptr_t ptr;
+
+ n = n ? n : 1;
+ if ((ptr = (p ? realloc(p, n) : malloc(n))) == (ptr_t) 0) {
+ child++;
+ stderror(ERR_NOMEM);
+ }
+ return ((char *) ptr);
+}
+
+char *
+Calloc(s, n)
+ size_t s, n;
+{
+ char *sptr;
+ ptr_t ptr;
+
+ n *= s;
+ n = n ? n : 1;
+ if ((ptr = malloc(n)) == (ptr_t) 0) {
+ child++;
+ stderror(ERR_NOMEM);
+ }
+
+ sptr = (char *) ptr;
+ if (n != 0)
+ do
+ *sptr++ = 0;
+ while (--n);
+
+ return ((char *) ptr);
+}
+
+void
+Free(p)
+ ptr_t p;
+{
+ if (p)
+ free(p);
+}
+
+#endif /* SYSMALLOC */
+
/*
* mstats - print out statistics about malloc
- *
+ *
* Prints two lines of numbers, one showing the length of the free list
* for each size category, the second showing the number of mallocs -
* frees for each size category.
*/
-showall(s)
-char **s;
+void
+/*ARGSUSED*/
+showall(v, t)
+ Char **v;
+ struct command *t;
{
- register int i, j;
- register union overhead *p;
- int totfree = 0,
- totused = 0;
-
- if (s[1])
- printf("Memory allocation statistics %s\nfree:", s[1]);
- for (i = 0; i < NBUCKETS; i++) {
- for (j = 0, p = nextf[i]; p; p = p->ov_next, j++)
- ;
- if (s[1])
- printf(" %d", j);
- totfree += j * (1 << (i + 3));
- }
- if (s[1])
- printf("\nused:");
- for (i = 0; i < NBUCKETS; i++) {
- if (s[1])
- printf(" %d", nmalloc[i]);
- totused += nmalloc[i] * (1 << (i + 3));
- }
- if (s[1])
- printf("\n");
- printf("Total in use: %d, total free: %d\n", totused, totfree);
+#ifndef SYSMALLOC
+ register int i, j;
+ register union overhead *p;
+ int totfree = 0, totused = 0;
+
+ (void) fprintf(cshout, "csh current memory allocation:\nfree:\t");
+ for (i = 0; i < NBUCKETS; i++) {
+ for (j = 0, p = nextf[i]; p; p = p->ov_next, j++);
+ (void) fprintf(cshout, " %4d", j);
+ totfree += j * (1 << (i + 3));
+ }
+ (void) fprintf(cshout, "\nused:\t");
+ for (i = 0; i < NBUCKETS; i++) {
+ (void) fprintf(cshout, "%4d", nmalloc[i]);
+ totused += nmalloc[i] * (1 << (i + 3));
+ }
+ (void) fprintf(cshout, "\n\tTotal in use: %d, total free: %d\n",
+ totused, totfree);
+ (void) fprintf(cshout,
+ "\tAllocated memory from 0x%lx to 0x%lx. Real top at 0x%lx\n",
+ membot, memtop, (char *) sbrk(0));
+#else
+ (void) fprintf(cshout, "Allocated memory from 0x%lx to 0x%lx (%ld).\n",
+ membot, memtop = (char *) sbrk(0), memtop - membot);
+#endif /* SYSMALLOC */
}