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-rw-r--r--generic/tclAlloc.c294
1 files changed, 151 insertions, 143 deletions
diff --git a/generic/tclAlloc.c b/generic/tclAlloc.c
index f51b039..8c1218d 100644
--- a/generic/tclAlloc.c
+++ b/generic/tclAlloc.c
@@ -15,7 +15,7 @@
* See the file "license.terms" for information on usage and redistribution
* of this file, and for a DISCLAIMER OF ALL WARRANTIES.
*
- * RCS: @(#) $Id: tclAlloc.c,v 1.20 2004/05/04 20:09:33 dgp Exp $
+ * RCS: @(#) $Id: tclAlloc.c,v 1.21 2004/10/06 12:44:52 dkf Exp $
*/
/*
@@ -44,34 +44,34 @@ typedef unsigned long caddr_t;
/*
* The overhead on a block is at least 8 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
+ * 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.
+ * 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 */
- unsigned char ov_padding[8]; /* Ensure the structure is 8-byte aligned. */
+ union overhead *next; /* when free */
+ unsigned char padding[8]; /* Ensure the structure is 8-byte
+ * aligned. */
struct {
- unsigned char ovu_magic0; /* magic number */
- unsigned char ovu_index; /* bucket # */
- unsigned char ovu_unused; /* unused */
- unsigned char ovu_magic1; /* other magic number */
+ unsigned char magic0; /* magic number */
+ unsigned char index; /* bucket # */
+ unsigned char unused; /* unused */
+ unsigned char magic1; /* other magic number */
#ifdef RCHECK
- unsigned short ovu_rmagic; /* range magic number */
- unsigned long ovu_size; /* actual block size */
- unsigned short ovu_unused2; /* padding to 8-byte align */
+ unsigned short rmagic; /* range magic number */
+ unsigned long size; /* actual block size */
+ unsigned short unused2; /* padding to 8-byte align */
#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
+ } ovu;
+#define overMagic0 ovu.magic0
+#define overMagic1 ovu.magic1
+#define bucketIndex ovu.index
+#define rangeCheckMagic ovu.rmagic
+#define realBlockSize ovu.size
};
@@ -87,6 +87,13 @@ union overhead {
#define OVERHEAD (sizeof(union overhead) + RSLOP)
/*
+ * Macro to make it easier to refer to the end-of-block guard magic.
+ */
+
+#define BLOCK_END(overPtr) \
+ (*(unsigned short *)((caddr_t)((overPtr) + 1) + (overPtr)->realBlockSize))
+
+/*
* 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.
@@ -129,11 +136,11 @@ static int allocInit = 0;
#ifdef MSTATS
/*
- * nmalloc[i] is the difference between the number of mallocs and frees
+ * numMallocs[i] is the difference between the number of mallocs and frees
* for a given block size.
*/
-static unsigned int nmalloc[NBUCKETS+1];
+static unsigned int numMallocs[NBUCKETS+1];
#include <stdio.h>
#endif
@@ -227,11 +234,11 @@ TclFinalizeAllocSubsystem()
for (i = 0; i < NBUCKETS; i++) {
nextf[i] = NULL;
#ifdef MSTATS
- nmalloc[i] = 0;
+ numMallocs[i] = 0;
#endif
}
#ifdef MSTATS
- nmalloc[i] = 0;
+ numMallocs[i] = 0;
#endif
Tcl_MutexUnlock(allocMutexPtr);
}
@@ -253,12 +260,12 @@ TclFinalizeAllocSubsystem()
*/
char *
-TclpAlloc(nbytes)
- unsigned int nbytes; /* Number of bytes to allocate. */
+TclpAlloc(numBytes)
+ unsigned int numBytes; /* Number of bytes to allocate. */
{
- register union overhead *op;
+ register union overhead *overPtr;
register long bucket;
- register unsigned amt;
+ register unsigned amount;
struct block *bigBlockPtr;
if (!allocInit) {
@@ -273,9 +280,9 @@ TclpAlloc(nbytes)
/*
* First the simple case: we simple allocate big blocks directly
*/
- if (nbytes + OVERHEAD >= MAXMALLOC) {
+ if (numBytes + OVERHEAD >= MAXMALLOC) {
bigBlockPtr = (struct block *) TclpSysAlloc((unsigned)
- (sizeof(struct block) + OVERHEAD + nbytes), 0);
+ (sizeof(struct block) + OVERHEAD + numBytes), 0);
if (bigBlockPtr == NULL) {
Tcl_MutexUnlock(allocMutexPtr);
return NULL;
@@ -285,23 +292,23 @@ TclpAlloc(nbytes)
bigBlockPtr->prevPtr = &bigBlocks;
bigBlockPtr->nextPtr->prevPtr = bigBlockPtr;
- op = (union overhead *) (bigBlockPtr + 1);
- op->ov_magic0 = op->ov_magic1 = MAGIC;
- op->ov_index = 0xff;
+ overPtr = (union overhead *) (bigBlockPtr + 1);
+ overPtr->overMagic0 = overPtr->overMagic1 = MAGIC;
+ overPtr->bucketIndex = 0xff;
#ifdef MSTATS
- nmalloc[NBUCKETS]++;
+ numMallocs[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;
+ overPtr->realBlockSize = (numBytes + RSLOP - 1) & ~(RSLOP - 1);
+ overPtr->rangeCheckMagic = RMAGIC;
+ BLOCK_END(overPtr) = RMAGIC;
#endif
Tcl_MutexUnlock(allocMutexPtr);
- return (void *)(op+1);
+ return (void *)(overPtr+1);
}
/*
* Convert amount of memory requested into closest block size
@@ -309,29 +316,29 @@ TclpAlloc(nbytes)
* Account for space used per block for accounting.
*/
#ifndef RCHECK
- amt = 8; /* size of first bucket */
+ amount = 8; /* size of first bucket */
bucket = 0;
#else
- amt = 16; /* size of first bucket */
+ amount = 16; /* size of first bucket */
bucket = 1;
#endif
- while (nbytes + OVERHEAD > amt) {
- amt <<= 1;
- if (amt == 0) {
+ while (numBytes + OVERHEAD > amount) {
+ amount <<= 1;
+ if (amount == 0) {
Tcl_MutexUnlock(allocMutexPtr);
return (NULL);
}
bucket++;
}
- ASSERT( bucket < NBUCKETS );
+ ASSERT(bucket < NBUCKETS);
/*
* If nothing in hash bucket right now,
* request more memory from the system.
*/
- if ((op = nextf[bucket]) == NULL) {
+ if ((overPtr = nextf[bucket]) == NULL) {
MoreCore(bucket);
- if ((op = nextf[bucket]) == NULL) {
+ if ((overPtr = nextf[bucket]) == NULL) {
Tcl_MutexUnlock(allocMutexPtr);
return (NULL);
}
@@ -339,23 +346,23 @@ TclpAlloc(nbytes)
/*
* Remove from linked list
*/
- nextf[bucket] = op->ov_next;
- op->ov_magic0 = op->ov_magic1 = MAGIC;
- op->ov_index = (unsigned char) bucket;
+ nextf[bucket] = overPtr->next;
+ overPtr->overMagic0 = overPtr->overMagic1 = MAGIC;
+ overPtr->bucketIndex = (unsigned char) bucket;
#ifdef MSTATS
- nmalloc[bucket]++;
+ numMallocs[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;
+ overPtr->realBlockSize = (numBytes + RSLOP - 1) & ~(RSLOP - 1);
+ overPtr->rangeCheckMagic = RMAGIC;
+ BLOCK_END(overPtr) = RMAGIC;
#endif
Tcl_MutexUnlock(allocMutexPtr);
- return ((char *)(op + 1));
+ return ((char *)(overPtr + 1));
}
/*
@@ -378,27 +385,27 @@ TclpAlloc(nbytes)
static void
MoreCore(bucket)
- int bucket; /* What bucket to allocat to. */
+ int bucket; /* What bucket to allocat to. */
{
- register union overhead *op;
- register long sz; /* size of desired block */
- long amt; /* amount to allocate */
- int nblks; /* how many blocks we get */
+ register union overhead *overPtr;
+ register long size; /* size of desired block */
+ long amount; /* amount to allocate */
+ int numBlocks; /* how many blocks we get */
struct block *blockPtr;
/*
* 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);
+ size = 1 << (bucket + 3);
+ ASSERT(size > 0);
- amt = MAXMALLOC;
- nblks = amt / sz;
- ASSERT(nblks*sz == amt);
+ amount = MAXMALLOC;
+ numBlocks = amount / size;
+ ASSERT(numBlocks*size == amount);
blockPtr = (struct block *) TclpSysAlloc((unsigned)
- (sizeof(struct block) + amt), 1);
+ (sizeof(struct block) + amount), 1);
/* no more room! */
if (blockPtr == NULL) {
return;
@@ -406,18 +413,18 @@ MoreCore(bucket)
blockPtr->nextPtr = blockList;
blockList = blockPtr;
- op = (union overhead *) (blockPtr + 1);
+ overPtr = (union overhead *) (blockPtr + 1);
/*
* 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);
+ nextf[bucket] = overPtr;
+ while (--numBlocks > 0) {
+ overPtr->next = (union overhead *)((caddr_t)overPtr + size);
+ overPtr = (union overhead *)((caddr_t)overPtr + size);
}
- op->ov_next = (union overhead *)NULL;
+ overPtr->next = (union overhead *)NULL;
}
/*
@@ -437,35 +444,35 @@ MoreCore(bucket)
*/
void
-TclpFree(cp)
- char *cp; /* Pointer to memory to free. */
+TclpFree(oldPtr)
+ char *oldPtr; /* Pointer to memory to free. */
{
register long size;
- register union overhead *op;
+ register union overhead *overPtr;
struct block *bigBlockPtr;
- if (cp == NULL) {
+ if (oldPtr == NULL) {
return;
}
Tcl_MutexLock(allocMutexPtr);
- op = (union overhead *)((caddr_t)cp - sizeof (union overhead));
+ overPtr = (union overhead *)((caddr_t)oldPtr - 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) {
+ ASSERT(overPtr->overMagic0 == MAGIC); /* make sure it was in use */
+ ASSERT(overPtr->overMagic1 == MAGIC);
+ if (overPtr->overMagic0 != MAGIC || overPtr->overMagic1 != MAGIC) {
Tcl_MutexUnlock(allocMutexPtr);
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 ) {
+ RANGE_ASSERT(overPtr->rangeCheckMagic == RMAGIC);
+ RANGE_ASSERT(BLOCK_END(overPtr) == RMAGIC);
+ size = overPtr->bucketIndex;
+ if (size == 0xff) {
#ifdef MSTATS
- nmalloc[NBUCKETS]--;
+ numMallocs[NBUCKETS]--;
#endif
- bigBlockPtr = (struct block *) op - 1;
+ bigBlockPtr = (struct block *) overPtr - 1;
bigBlockPtr->prevPtr->nextPtr = bigBlockPtr->nextPtr;
bigBlockPtr->nextPtr->prevPtr = bigBlockPtr->prevPtr;
TclpSysFree(bigBlockPtr);
@@ -473,10 +480,10 @@ TclpFree(cp)
return;
}
ASSERT(size < NBUCKETS);
- op->ov_next = nextf[size]; /* also clobbers ov_magic */
- nextf[size] = op;
+ overPtr->next = nextf[size]; /* also clobbers overMagic */
+ nextf[size] = overPtr;
#ifdef MSTATS
- nmalloc[size]--;
+ numMallocs[size]--;
#endif
Tcl_MutexUnlock(allocMutexPtr);
}
@@ -498,34 +505,34 @@ TclpFree(cp)
*/
char *
-TclpRealloc(cp, nbytes)
- char *cp; /* Pointer to alloced block. */
- unsigned int nbytes; /* New size of memory. */
+TclpRealloc(oldPtr, numBytes)
+ char *oldPtr; /* Pointer to alloced block. */
+ unsigned int numBytes; /* New size of memory. */
{
int i;
- union overhead *op;
+ union overhead *overPtr;
struct block *bigBlockPtr;
int expensive;
- unsigned long maxsize;
+ unsigned long maxSize;
- if (cp == NULL) {
- return (TclpAlloc(nbytes));
+ if (oldPtr == NULL) {
+ return (TclpAlloc(numBytes));
}
Tcl_MutexLock(allocMutexPtr);
- op = (union overhead *)((caddr_t)cp - sizeof (union overhead));
+ overPtr = (union overhead *)((caddr_t)oldPtr - 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) {
+ ASSERT(overPtr->overMagic0 == MAGIC); /* make sure it was in use */
+ ASSERT(overPtr->overMagic1 == MAGIC);
+ if (overPtr->overMagic0 != MAGIC || overPtr->overMagic1 != MAGIC) {
Tcl_MutexUnlock(allocMutexPtr);
return NULL;
}
- RANGE_ASSERT(op->ov_rmagic == RMAGIC);
- RANGE_ASSERT(*(unsigned short *)((caddr_t)(op + 1) + op->ov_size) == RMAGIC);
- i = op->ov_index;
+ RANGE_ASSERT(overPtr->rangeCheckMagic == RMAGIC);
+ RANGE_ASSERT(BLOCK_END(overPtr) == RMAGIC);
+ i = overPtr->bucketIndex;
/*
* If the block isn't in a bin, just realloc it.
@@ -533,11 +540,11 @@ TclpRealloc(cp, nbytes)
if (i == 0xff) {
struct block *prevPtr, *nextPtr;
- bigBlockPtr = (struct block *) op - 1;
+ bigBlockPtr = (struct block *) overPtr - 1;
prevPtr = bigBlockPtr->prevPtr;
nextPtr = bigBlockPtr->nextPtr;
bigBlockPtr = (struct block *) TclpSysRealloc(bigBlockPtr,
- sizeof(struct block) + OVERHEAD + nbytes);
+ sizeof(struct block) + OVERHEAD + numBytes);
if (bigBlockPtr == NULL) {
Tcl_MutexUnlock(allocMutexPtr);
return NULL;
@@ -553,55 +560,56 @@ TclpRealloc(cp, nbytes)
nextPtr->prevPtr = bigBlockPtr;
}
- op = (union overhead *) (bigBlockPtr + 1);
+ overPtr = (union overhead *) (bigBlockPtr + 1);
#ifdef MSTATS
- nmalloc[NBUCKETS]++;
+ numMallocs[NBUCKETS]++;
#endif
#ifdef RCHECK
/*
* Record allocated size of block and update magic number bounds.
*/
- op->ov_size = (nbytes + RSLOP - 1) & ~(RSLOP - 1);
- *(unsigned short *)((caddr_t)(op + 1) + op->ov_size) = RMAGIC;
+ overPtr->realBlockSize = (numBytes + RSLOP - 1) & ~(RSLOP - 1);
+ BLOCK_END(overPtr) = RMAGIC;
#endif
Tcl_MutexUnlock(allocMutexPtr);
- return (char *)(op+1);
+ return (char *)(overPtr+1);
}
- maxsize = 1 << (i+3);
+ maxSize = 1 << (i+3);
expensive = 0;
- if ( nbytes + OVERHEAD > maxsize ) {
+ if (numBytes+OVERHEAD > maxSize) {
expensive = 1;
- } else if ( i > 0 && nbytes + OVERHEAD < (maxsize/2) ) {
+ } else if (i>0 && numBytes+OVERHEAD < maxSize/2) {
expensive = 1;
}
if (expensive) {
- void *newp;
+ void *newPtr;
Tcl_MutexUnlock(allocMutexPtr);
- newp = TclpAlloc(nbytes);
- if ( newp == NULL ) {
+ newPtr = TclpAlloc(numBytes);
+ if (newPtr == NULL) {
return NULL;
}
- maxsize -= OVERHEAD;
- if ( maxsize < nbytes )
- nbytes = maxsize;
- memcpy((VOID *) newp, (VOID *) cp, (size_t) nbytes);
- TclpFree(cp);
- return newp;
+ maxSize -= OVERHEAD;
+ if (maxSize < numBytes) {
+ numBytes = maxSize;
+ }
+ memcpy((VOID *) newPtr, (VOID *) oldPtr, (size_t) numBytes);
+ TclpFree(oldPtr);
+ return newPtr;
}
/*
* 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;
+ overPtr->realBlockSize = (numBytes + RSLOP - 1) & ~(RSLOP - 1);
+ BLOCK_END(overPtr) = RMAGIC;
#endif
Tcl_MutexUnlock(allocMutexPtr);
- return(cp);
+ return(oldPtr);
}
/*
@@ -628,26 +636,26 @@ mstats(s)
char *s; /* Where to write info. */
{
register int i, j;
- register union overhead *p;
- int totfree = 0,
- totused = 0;
+ register union overhead *overPtr;
+ int totalFree = 0, totalUsed = 0;
Tcl_MutexLock(allocMutexPtr);
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++)
+ for (j=0, overPtr=nextf[i]; overPtr; overPtr=overPtr->next, j++) {
fprintf(stderr, " %d", j);
- totfree += j * (1 << (i + 3));
+ }
+ totalFree += 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, " %d", numMallocs[i]);
+ totalUsed += numMallocs[i] * (1 << (i + 3));
}
fprintf(stderr, "\n\tTotal small in use: %d, total free: %d\n",
- totused, totfree);
+ totalUsed, totalFree);
fprintf(stderr, "\n\tNumber of big (>%d) blocks in use: %d\n",
- MAXMALLOC, nmalloc[NBUCKETS]);
+ MAXMALLOC, numMallocs[NBUCKETS]);
Tcl_MutexUnlock(allocMutexPtr);
}
#endif
@@ -671,10 +679,10 @@ mstats(s)
*/
char *
-TclpAlloc(nbytes)
- unsigned int nbytes; /* Number of bytes to allocate. */
+TclpAlloc(numBytes)
+ unsigned int numBytes; /* Number of bytes to allocate. */
{
- return (char*) malloc(nbytes);
+ return (char*) malloc(numBytes);
}
/*
@@ -694,10 +702,10 @@ TclpAlloc(nbytes)
*/
void
-TclpFree(cp)
- char *cp; /* Pointer to memory to free. */
+TclpFree(oldPtr)
+ char *oldPtr; /* Pointer to memory to free. */
{
- free(cp);
+ free(oldPtr);
return;
}
@@ -718,11 +726,11 @@ TclpFree(cp)
*/
char *
-TclpRealloc(cp, nbytes)
- char *cp; /* Pointer to alloced block. */
- unsigned int nbytes; /* New size of memory. */
+TclpRealloc(oldPtr, numBytes)
+ char *oldPtr; /* Pointer to alloced block. */
+ unsigned int numBytes; /* New size of memory. */
{
- return (char*) realloc(cp, nbytes);
+ return (char*) realloc(oldPtr, numBytes);
}
#endif /* !USE_TCLALLOC */
generated by cgit v0.12 at 2024-11-05 07:45:14 (GMT)