659 lines
15 KiB
C
659 lines
15 KiB
C
/*
|
||
* tclMacAlloc.c --
|
||
*
|
||
* 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.
|
||
* Blocks over a certain size are directly allocated by calling NewPtr.
|
||
*
|
||
* Copyright (c) 1983 Regents of the University of California.
|
||
* Copyright (c) 1996 Sun Microsystems, Inc.
|
||
*
|
||
* Portions contributed by Chris Kingsley, Jack Jansen and Ray Johnson
|
||
*.
|
||
* See the file "license.terms" for information on usage and redistribution
|
||
* of this file, and for a DISCLAIMER OF ALL WARRANTIES.
|
||
*
|
||
* SCCS: @(#) tclMacAlloc.c 1.7 96/09/22 15:37:03
|
||
*/
|
||
|
||
#ifdef TCL_DEBUG
|
||
# define DEBUG
|
||
/* #define MSTATS */
|
||
# define RCHECK
|
||
#endif
|
||
|
||
typedef unsigned long caddr_t;
|
||
|
||
#include "tclMacInt.h"
|
||
#include <Memory.h>
|
||
#include <stdlib.h>
|
||
#include <string.h>
|
||
|
||
/*
|
||
* Flags that are used by ConfigureMemory to define how the allocator
|
||
* should work. They can be or'd together.
|
||
*/
|
||
#define MEMORY_ALL_SYS 1 /* All memory should come from the system heap. */
|
||
|
||
static int memoryFlags = 0;
|
||
|
||
/*
|
||
* 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.
|
||
*/
|
||
union overhead {
|
||
union overhead *ov_next; /* when free */
|
||
struct {
|
||
unsigned char ovu_magic0; /* magic number */
|
||
unsigned char ovu_index; /* bucket # */
|
||
unsigned char ovu_unused; /* unused */
|
||
unsigned char ovu_magic1; /* other magic number */
|
||
#ifdef RCHECK
|
||
unsigned short ovu_rmagic; /* range magic number */
|
||
unsigned long ovu_size; /* actual block size */
|
||
#endif
|
||
} ovu;
|
||
#define ov_magic0 ovu.ovu_magic0
|
||
#define ov_magic1 ovu.ovu_magic1
|
||
#define ov_index ovu.ovu_index
|
||
#define ov_rmagic ovu.ovu_rmagic
|
||
#define ov_size ovu.ovu_size
|
||
};
|
||
|
||
#define MAGIC 0xef /* magic # on accounting info */
|
||
#define RMAGIC 0x5555 /* magic # on range info */
|
||
|
||
#ifdef RCHECK
|
||
#define RSLOP sizeof (unsigned short)
|
||
#else
|
||
#define RSLOP 0
|
||
#endif
|
||
|
||
#define OVERHEAD (sizeof(union overhead) + RSLOP)
|
||
|
||
/*
|
||
* nextf[i] is the pointer to the next free block of size 2^(i+3). The
|
||
* smallest allocatable block is 8 bytes. The overhead information
|
||
* precedes the data area returned to the user.
|
||
*/
|
||
/*#define NBUCKETS 11*/
|
||
#define NBUCKETS 13
|
||
#define MAXMALLOC (1<<(NBUCKETS+2))
|
||
static union overhead *nextf[NBUCKETS];
|
||
|
||
#ifdef MSTATS
|
||
/*
|
||
* nmalloc[i] is the difference between the number of mallocs and frees
|
||
* for a given block size.
|
||
*/
|
||
static unsigned int nmalloc[NBUCKETS+1];
|
||
#include <stdio.h>
|
||
#endif
|
||
|
||
/*
|
||
* The following typedef and variable are used to keep track of memory
|
||
* blocks that are allocated directly from the System Heap. This chunks
|
||
* of memory must always be freed - even if we crash.
|
||
*/
|
||
typedef struct listEl {
|
||
Handle memoryHandle;
|
||
struct listEl * next;
|
||
} ListEl;
|
||
|
||
ListEl * systemMemory = NULL;
|
||
ListEl * appMemory = NULL;
|
||
|
||
#if defined(DEBUG) || defined(RCHECK)
|
||
#define ASSERT(p) if (!(p)) panic(# p)
|
||
#define RANGE_ASSERT(p) if (!(p)) panic(# p)
|
||
#else
|
||
#define ASSERT(p)
|
||
#define RANGE_ASSERT(p)
|
||
#endif
|
||
|
||
/*
|
||
* Prototypes for functions used only in this file.
|
||
*/
|
||
static void MoreCore _ANSI_ARGS_(());
|
||
static void * SysAlloc _ANSI_ARGS_((long size, int high));
|
||
static void SysFree _ANSI_ARGS_((void * ptr));
|
||
static pascal void CleanUpExitProc _ANSI_ARGS_((void));
|
||
void ConfigureMemory _ANSI_ARGS_((int flags));
|
||
void FreeAllMemory _ANSI_ARGS_((void));
|
||
|
||
/*
|
||
*----------------------------------------------------------------------
|
||
*
|
||
* TclpAlloc --
|
||
*
|
||
* Allocate more memory.
|
||
*
|
||
* Results:
|
||
* None.
|
||
*
|
||
* Side effects:
|
||
* None.
|
||
*
|
||
*----------------------------------------------------------------------
|
||
*/
|
||
|
||
char *
|
||
TclpAlloc(nbytes)
|
||
size_t nbytes;
|
||
{
|
||
register union overhead *op;
|
||
register long bucket;
|
||
register unsigned amt;
|
||
|
||
/*
|
||
* First the simple case: we simple allocate big blocks directly
|
||
*/
|
||
if ( nbytes + OVERHEAD >= MAXMALLOC ) {
|
||
op = (union overhead *)SysAlloc(nbytes+OVERHEAD, false);
|
||
if ( op == NULL )
|
||
return NULL;
|
||
op->ov_magic0 = op->ov_magic1 = MAGIC;
|
||
op->ov_index = 0xff;
|
||
#ifdef MSTATS
|
||
nmalloc[NBUCKETS]++;
|
||
#endif
|
||
#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;
|
||
*(unsigned short *)((caddr_t)(op + 1) + op->ov_size) = RMAGIC;
|
||
#endif
|
||
return (void *)(op+1);
|
||
}
|
||
/*
|
||
* Convert amount of memory requested into closest block size
|
||
* stored in hash buckets which satisfies request.
|
||
* Account for space used per block for accounting.
|
||
*/
|
||
#ifndef RCHECK
|
||
amt = 8; /* size of first bucket */
|
||
bucket = 0;
|
||
#else
|
||
amt = 16; /* size of first bucket */
|
||
bucket = 1;
|
||
#endif
|
||
while (nbytes + OVERHEAD > amt) {
|
||
amt <<= 1;
|
||
if (amt == 0)
|
||
return (NULL);
|
||
bucket++;
|
||
}
|
||
ASSERT( bucket < NBUCKETS );
|
||
|
||
/*
|
||
* 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_magic0 = op->ov_magic1 = MAGIC;
|
||
op->ov_index = bucket;
|
||
#ifdef MSTATS
|
||
nmalloc[bucket]++;
|
||
#endif
|
||
#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;
|
||
*(unsigned short *)((caddr_t)(op + 1) + op->ov_size) = RMAGIC;
|
||
#endif
|
||
return ((char *)(op + 1));
|
||
}
|
||
|
||
/*
|
||
*----------------------------------------------------------------------
|
||
*
|
||
* MoreCore --
|
||
*
|
||
* Allocate more memory to the indicated bucket.
|
||
*
|
||
* Results:
|
||
* None.
|
||
*
|
||
* Side effects:
|
||
* Attempts to get more memory from the system.
|
||
*
|
||
*----------------------------------------------------------------------
|
||
*/
|
||
|
||
static void
|
||
MoreCore(bucket)
|
||
int bucket;
|
||
{
|
||
register union overhead *op;
|
||
register long sz; /* size of desired block */
|
||
long amt; /* amount to allocate */
|
||
int nblks; /* how many blocks we get */
|
||
|
||
/*
|
||
* 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);
|
||
ASSERT(sz > 0);
|
||
|
||
amt = MAXMALLOC;
|
||
nblks = amt / sz;
|
||
ASSERT(nblks*sz == amt);
|
||
|
||
op = (union overhead *)SysAlloc(amt, true);
|
||
/* no more room! */
|
||
if (op == NULL)
|
||
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);
|
||
}
|
||
op->ov_next = (union overhead *)NULL;
|
||
}
|
||
|
||
/*
|
||
*----------------------------------------------------------------------
|
||
*
|
||
* TclpFree --
|
||
*
|
||
* Free memory.
|
||
*
|
||
* Results:
|
||
* None.
|
||
*
|
||
* Side effects:
|
||
* None.
|
||
*
|
||
*----------------------------------------------------------------------
|
||
*/
|
||
|
||
void
|
||
TclpFree(cp)
|
||
char *cp;
|
||
{
|
||
register long size;
|
||
register union overhead *op;
|
||
|
||
if (cp == NULL) {
|
||
return;
|
||
}
|
||
|
||
op = (union overhead *)((caddr_t)cp - sizeof (union overhead));
|
||
|
||
ASSERT(op->ov_magic0 == MAGIC); /* make sure it was in use */
|
||
ASSERT(op->ov_magic1 == MAGIC);
|
||
if (op->ov_magic0 != MAGIC || op->ov_magic1 != MAGIC) {
|
||
return;
|
||
}
|
||
|
||
RANGE_ASSERT(op->ov_rmagic == RMAGIC);
|
||
RANGE_ASSERT(*(unsigned short *)((caddr_t)(op + 1) + op->ov_size) == RMAGIC);
|
||
size = op->ov_index;
|
||
if ( size == 0xff ) {
|
||
#ifdef MSTATS
|
||
nmalloc[NBUCKETS]--;
|
||
#endif
|
||
SysFree((Ptr) op);
|
||
return;
|
||
}
|
||
ASSERT(size < NBUCKETS);
|
||
op->ov_next = nextf[size]; /* also clobbers ov_magic */
|
||
nextf[size] = op;
|
||
#ifdef MSTATS
|
||
nmalloc[size]--;
|
||
#endif
|
||
}
|
||
|
||
/*
|
||
*----------------------------------------------------------------------
|
||
*
|
||
* TclpRealloc --
|
||
*
|
||
* Reallocate memory.
|
||
*
|
||
* Results:
|
||
* None.
|
||
*
|
||
* Side effects:
|
||
* None.
|
||
*
|
||
*----------------------------------------------------------------------
|
||
*/
|
||
|
||
char *
|
||
TclpRealloc(cp, nbytes)
|
||
char *cp;
|
||
size_t nbytes;
|
||
{
|
||
int i;
|
||
union overhead *op;
|
||
int expensive;
|
||
unsigned long maxsize;
|
||
|
||
if (cp == NULL) {
|
||
return (TclpAlloc(nbytes));
|
||
}
|
||
|
||
op = (union overhead *)((caddr_t)cp - sizeof (union overhead));
|
||
|
||
ASSERT(op->ov_magic0 == MAGIC); /* make sure it was in use */
|
||
ASSERT(op->ov_magic1 == MAGIC);
|
||
if (op->ov_magic0 != MAGIC || op->ov_magic1 != MAGIC) {
|
||
return NULL;
|
||
}
|
||
|
||
RANGE_ASSERT(op->ov_rmagic == RMAGIC);
|
||
RANGE_ASSERT(*(unsigned short *)((caddr_t)(op + 1) + op->ov_size) == RMAGIC);
|
||
i = op->ov_index;
|
||
/*
|
||
* First the malloc/copy cases
|
||
*/
|
||
expensive = 0;
|
||
if ( i == 0xff ) {
|
||
Handle hand;
|
||
|
||
hand = * (Handle *) ((Ptr) op - sizeof(Handle));
|
||
maxsize = GetHandleSize(hand) - sizeof(Handle);
|
||
expensive = 1;
|
||
} else {
|
||
maxsize = 1 << (i+3);
|
||
if ( nbytes + OVERHEAD > maxsize ) {
|
||
expensive = 1;
|
||
} else if ( i > 0 && nbytes + OVERHEAD < (maxsize/2) ) {
|
||
expensive = 1;
|
||
}
|
||
}
|
||
|
||
if (expensive) {
|
||
void *newp;
|
||
|
||
newp = TclpAlloc(nbytes);
|
||
if ( newp == NULL ) {
|
||
return NULL;
|
||
}
|
||
maxsize -= OVERHEAD;
|
||
if ( maxsize < nbytes )
|
||
nbytes = maxsize;
|
||
memcpy(newp, cp, nbytes);
|
||
TclpFree(cp);
|
||
return newp;
|
||
}
|
||
|
||
/*
|
||
* Ok, we don't have to copy, it fits as-is
|
||
*/
|
||
#ifdef RCHECK
|
||
op->ov_size = (nbytes + RSLOP - 1) & ~(RSLOP - 1);
|
||
*(unsigned short *)((caddr_t)(op + 1) + op->ov_size) = RMAGIC;
|
||
#endif
|
||
return(cp);
|
||
}
|
||
|
||
/*
|
||
*----------------------------------------------------------------------
|
||
*
|
||
* mstats --
|
||
*
|
||
* 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.
|
||
*
|
||
* Results:
|
||
* None.
|
||
*
|
||
* Side effects:
|
||
* None.
|
||
*
|
||
*----------------------------------------------------------------------
|
||
*/
|
||
|
||
#ifdef MSTATS
|
||
void
|
||
mstats(s)
|
||
char *s;
|
||
{
|
||
register int i, j;
|
||
register union overhead *p;
|
||
int totfree = 0,
|
||
totused = 0;
|
||
|
||
fprintf(stderr, "Memory allocation statistics %s\nTclpFree:\t", s);
|
||
for (i = 0; i < NBUCKETS; i++) {
|
||
for (j = 0, p = nextf[i]; p; p = p->ov_next, j++)
|
||
fprintf(stderr, " %d", j);
|
||
totfree += j * (1 << (i + 3));
|
||
}
|
||
fprintf(stderr, "\nused:\t");
|
||
for (i = 0; i < NBUCKETS; i++) {
|
||
fprintf(stderr, " %d", nmalloc[i]);
|
||
totused += nmalloc[i] * (1 << (i + 3));
|
||
}
|
||
fprintf(stderr, "\n\tTotal small in use: %d, total free: %d\n",
|
||
totused, totfree);
|
||
fprintf(stderr, "\n\tNumber of big (>%d) blocks in use: %d\n",
|
||
MAXMALLOC, nmalloc[NBUCKETS]);
|
||
}
|
||
#endif
|
||
|
||
/*
|
||
*----------------------------------------------------------------------
|
||
*
|
||
* SysAlloc --
|
||
*
|
||
* Allocate a new block of memory free from the System.
|
||
*
|
||
* Results:
|
||
* Returns a pointer to a new block of memory.
|
||
*
|
||
* Side effects:
|
||
* May obtain memory from app or sys space. Info is added to
|
||
* overhead lists etc..
|
||
*
|
||
*----------------------------------------------------------------------
|
||
*/
|
||
|
||
static void *
|
||
SysAlloc(
|
||
long size,
|
||
int high)
|
||
{
|
||
Handle hand = NULL;
|
||
ListEl * newMemoryRecord;
|
||
|
||
if (!(memoryFlags & MEMORY_ALL_SYS)) {
|
||
hand = NewHandle(size + sizeof(Handle));
|
||
}
|
||
if (hand != NULL) {
|
||
newMemoryRecord = (ListEl *) NewPtr(sizeof(ListEl));
|
||
if (newMemoryRecord == NULL) {
|
||
DisposeHandle(hand);
|
||
return NULL;
|
||
}
|
||
newMemoryRecord->memoryHandle = hand;
|
||
newMemoryRecord->next = appMemory;
|
||
appMemory = newMemoryRecord;
|
||
} else {
|
||
/*
|
||
* Ran out of memory in application space. Lets try to get
|
||
* more memory from system. Otherwise, we return NULL to
|
||
* denote failure.
|
||
*/
|
||
high = false;
|
||
hand = NewHandleSys(size);
|
||
if (hand == NULL) {
|
||
return NULL;
|
||
}
|
||
if (systemMemory == NULL) {
|
||
/*
|
||
* This is the first time we've attempted to allocate memory
|
||
* directly from the system heap. We need to now install the
|
||
* exit handle to ensure the memory is cleaned up.
|
||
*/
|
||
/* TclMacInstallExitToShellPatch(CleanUpExitProc); */
|
||
}
|
||
newMemoryRecord = (ListEl *) NewPtrSys(sizeof(ListEl));
|
||
if (newMemoryRecord == NULL) {
|
||
DisposeHandle(hand);
|
||
return NULL;
|
||
}
|
||
newMemoryRecord->memoryHandle = hand;
|
||
newMemoryRecord->next = systemMemory;
|
||
systemMemory = newMemoryRecord;
|
||
}
|
||
if (high) {
|
||
HLockHi(hand);
|
||
} else {
|
||
HLock(hand);
|
||
}
|
||
(** (Handle **) hand) = hand;
|
||
|
||
return (*hand + sizeof(Handle));
|
||
}
|
||
|
||
/*
|
||
*----------------------------------------------------------------------
|
||
*
|
||
* SysFree --
|
||
*
|
||
* Free memory that we aloocated back to the system.
|
||
*
|
||
* Results:
|
||
* None.
|
||
*
|
||
* Side effects:
|
||
* Memory is freed.
|
||
*
|
||
*----------------------------------------------------------------------
|
||
*/
|
||
|
||
static void
|
||
SysFree(void * ptr)
|
||
{
|
||
Handle hand;
|
||
OSErr err;
|
||
|
||
hand = * (Handle *) ((Ptr) ptr - sizeof(Handle));
|
||
DisposeHandle(hand);
|
||
err = MemError();
|
||
}
|
||
|
||
/*
|
||
*----------------------------------------------------------------------
|
||
*
|
||
* CleanUpExitProc --
|
||
*
|
||
* This procedure is invoked as an exit handler when ExitToShell
|
||
* is called. It removes any memory that was allocated directly
|
||
* from the system heap. This must be called when the application
|
||
* quits or the memory will never be freed.
|
||
*
|
||
* Results:
|
||
* None.
|
||
*
|
||
* Side effects:
|
||
* May free memory in the system heap.
|
||
*
|
||
*----------------------------------------------------------------------
|
||
*/
|
||
|
||
static pascal void
|
||
CleanUpExitProc()
|
||
{
|
||
ListEl * memRecord;
|
||
|
||
while (systemMemory != NULL) {
|
||
memRecord = systemMemory;
|
||
systemMemory = memRecord->next;
|
||
DisposeHandle(memRecord->memoryHandle);
|
||
DisposePtr((void *) memRecord);
|
||
}
|
||
}
|
||
|
||
/*
|
||
*----------------------------------------------------------------------
|
||
*
|
||
* FreeAllMemory --
|
||
*
|
||
* This procedure frees all memory blocks allocated by the memory
|
||
* sub-system. Make sure you don't have any code that references
|
||
* any malloced data!
|
||
*
|
||
* Results:
|
||
* None.
|
||
*
|
||
* Side effects:
|
||
* Frees all memory allocated by TclpAlloc.
|
||
*
|
||
*----------------------------------------------------------------------
|
||
*/
|
||
|
||
void
|
||
FreeAllMemory()
|
||
{
|
||
ListEl * memRecord;
|
||
|
||
while (systemMemory != NULL) {
|
||
memRecord = systemMemory;
|
||
systemMemory = memRecord->next;
|
||
DisposeHandle(memRecord->memoryHandle);
|
||
DisposePtr((void *) memRecord);
|
||
}
|
||
while (appMemory != NULL) {
|
||
memRecord = appMemory;
|
||
appMemory = memRecord->next;
|
||
DisposeHandle(memRecord->memoryHandle);
|
||
DisposePtr((void *) memRecord);
|
||
}
|
||
}
|
||
|
||
/*
|
||
*----------------------------------------------------------------------
|
||
*
|
||
* ConfigureMemory --
|
||
*
|
||
* This procedure sets certain flags in this file that control
|
||
* how memory is allocated and managed. This call must be made
|
||
* before any call to TclpAlloc is made.
|
||
*
|
||
* Results:
|
||
* None.
|
||
*
|
||
* Side effects:
|
||
* Certain state will be changed.
|
||
*
|
||
*----------------------------------------------------------------------
|
||
*/
|
||
|
||
void
|
||
ConfigureMemory(
|
||
int flags)
|
||
{
|
||
memoryFlags = flags;
|
||
}
|