Merge commit '9966985d896629eede849a84f18e406d1164a16c' as 'tcl8.6'

1 files changed, 759 insertions, 0 deletions

diff --git a/tcl8.6/generic/tclAlloc.c b/tcl8.6/generic/tclAlloc.c
new file mode 100644
index 0000000..cda1f38
--- /dev/null
+++ b/tcl8.6/generic/tclAlloc.c
@@ -0,0 +1,759 @@
+/*
+ * tclAlloc.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 from the system.
+ *
+ * Copyright (c) 1983 Regents of the University of California.
+ * Copyright (c) 1996-1997 Sun Microsystems, Inc.
+ * Copyright (c) 1998-1999 by Scriptics Corporation.
+ *
+ * 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.
+ */
+
+/*
+ * Windows and Unix use an alternative allocator when building with threads
+ * that has significantly reduced lock contention.
+ */
+
+#include "tclInt.h"
+#if !defined(TCL_THREADS) || !defined(USE_THREAD_ALLOC)
+
+#if USE_TCLALLOC
+
+/*
+ * We should really make use of AC_CHECK_TYPE(caddr_t) here, but it can wait
+ * until Tcl uses config.h properly.
+ */
+
+#if defined(_MSC_VER) || defined(__MSVCRT__) || defined(__BORLANDC__)
+typedef unsigned long caddr_t;
+#endif
+
+/*
+ * 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 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 *next;		/* when free */
+    unsigned char padding[TCL_ALLOCALIGN];	/* align struct to TCL_ALLOCALIGN bytes */
+    struct {
+	unsigned char magic0;		/* magic number */
+	unsigned char index;		/* bucket # */
+	unsigned char unused;		/* unused */
+	unsigned char magic1;		/* other magic number */
+#ifndef NDEBUG
+	unsigned short rmagic;		/* range magic number */
+	unsigned long size;		/* actual block size */
+	unsigned short unused2;		/* padding to 8-byte align */
+#endif
+    } ovu;
+#define overMagic0	ovu.magic0
+#define overMagic1	ovu.magic1
+#define bucketIndex	ovu.index
+#define rangeCheckMagic	ovu.rmagic
+#define realBlockSize	ovu.size
+};
+
+
+#define MAGIC		0xef	/* magic # on accounting info */
+#define RMAGIC		0x5555	/* magic # on range info */
+
+#ifndef NDEBUG
+#define	RSLOP		sizeof(unsigned short)
+#else
+#define	RSLOP		0
+#endif
+
+#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 MINBLOCK bytes. The overhead information
+ * precedes the data area returned to the user.
+ */
+
+#define MINBLOCK	((sizeof(union overhead) + (TCL_ALLOCALIGN-1)) & ~(TCL_ALLOCALIGN-1))
+#define NBUCKETS	(13 - (MINBLOCK >> 4))
+#define MAXMALLOC	(1<<(NBUCKETS+2))
+static union overhead *nextf[NBUCKETS];
+
+/*
+ * The following structure is used to keep track of all system memory
+ * currently owned by Tcl. When finalizing, all this memory will be returned
+ * to the system.
+ */
+
+struct block {
+    struct block *nextPtr;	/* Linked list. */
+    struct block *prevPtr;	/* Linked list for big blocks, ensures 8-byte
+				 * alignment for suballocated blocks. */
+};
+
+static struct block *blockList;	/* Tracks the suballocated blocks. */
+static struct block bigBlocks={	/* Big blocks aren't suballocated. */
+    &bigBlocks, &bigBlocks
+};
+
+/*
+ * The allocator is protected by a special mutex that must be explicitly
+ * initialized. Futhermore, because Tcl_Alloc may be used before anything else
+ * in Tcl, we make this module self-initializing after all with the allocInit
+ * variable.
+ */
+
+#ifdef TCL_THREADS
+static Tcl_Mutex *allocMutexPtr;
+#endif
+static int allocInit = 0;
+
+#ifdef MSTATS
+
+/*
+ * numMallocs[i] is the difference between the number of mallocs and frees for
+ * a given block size.
+ */
+
+static	unsigned int numMallocs[NBUCKETS+1];
+#endif
+
+#if !defined(NDEBUG)
+#define	ASSERT(p)	if (!(p)) Tcl_Panic(# p)
+#define RANGE_ASSERT(p) if (!(p)) Tcl_Panic(# p)
+#else
+#define	ASSERT(p)
+#define RANGE_ASSERT(p)
+#endif
+
+/*
+ * Prototypes for functions used only in this file.
+ */
+
+static void		MoreCore(int bucket);
+
+/*
+ *-------------------------------------------------------------------------
+ *
+ * TclInitAlloc --
+ *
+ *	Initialize the memory system.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Initialize the mutex used to serialize allocations.
+ *
+ *-------------------------------------------------------------------------
+ */
+
+void
+TclInitAlloc(void)
+{
+    if (!allocInit) {
+	allocInit = 1;
+#ifdef TCL_THREADS
+	allocMutexPtr = Tcl_GetAllocMutex();
+#endif
+    }
+}
+
+/*
+ *-------------------------------------------------------------------------
+ *
+ * TclFinalizeAllocSubsystem --
+ *
+ *	Release all resources being used by this subsystem, including
+ *	aggressively freeing all memory allocated by TclpAlloc() that has not
+ *	yet been released with TclpFree().
+ *
+ *	After this function is called, all memory allocated with TclpAlloc()
+ *	should be considered unusable.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	This subsystem is self-initializing, since memory can be allocated
+ *	before Tcl is formally initialized. After this call, this subsystem
+ *	has been reset to its initial state and is usable again.
+ *
+ *-------------------------------------------------------------------------
+ */
+
+void
+TclFinalizeAllocSubsystem(void)
+{
+    unsigned int i;
+    struct block *blockPtr, *nextPtr;
+
+    Tcl_MutexLock(allocMutexPtr);
+    for (blockPtr = blockList; blockPtr != NULL; blockPtr = nextPtr) {
+	nextPtr = blockPtr->nextPtr;
+	TclpSysFree(blockPtr);
+    }
+    blockList = NULL;
+
+    for (blockPtr = bigBlocks.nextPtr; blockPtr != &bigBlocks; ) {
+	nextPtr = blockPtr->nextPtr;
+	TclpSysFree(blockPtr);
+	blockPtr = nextPtr;
+    }
+    bigBlocks.nextPtr = &bigBlocks;
+    bigBlocks.prevPtr = &bigBlocks;
+
+    for (i=0 ; i<NBUCKETS ; i++) {
+	nextf[i] = NULL;
+#ifdef MSTATS
+	numMallocs[i] = 0;
+#endif
+    }
+#ifdef MSTATS
+    numMallocs[i] = 0;
+#endif
+    Tcl_MutexUnlock(allocMutexPtr);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclpAlloc --
+ *
+ *	Allocate more memory.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+char *
+TclpAlloc(
+    unsigned int numBytes)	/* Number of bytes to allocate. */
+{
+    register union overhead *overPtr;
+    register long bucket;
+    register unsigned amount;
+    struct block *bigBlockPtr = NULL;
+
+    if (!allocInit) {
+	/*
+	 * We have to make the "self initializing" because Tcl_Alloc may be
+	 * used before any other part of Tcl. E.g., see main() for tclsh!
+	 */
+
+	TclInitAlloc();
+    }
+    Tcl_MutexLock(allocMutexPtr);
+
+    /*
+     * First the simple case: we simple allocate big blocks directly.
+     */
+
+    if (numBytes >= MAXMALLOC - OVERHEAD) {
+	if (numBytes <= UINT_MAX - OVERHEAD -sizeof(struct block)) {
+	    bigBlockPtr = (struct block *) TclpSysAlloc((unsigned)
+		    (sizeof(struct block) + OVERHEAD + numBytes), 0);
+	}
+	if (bigBlockPtr == NULL) {
+	    Tcl_MutexUnlock(allocMutexPtr);
+	    return NULL;
+	}
+	bigBlockPtr->nextPtr = bigBlocks.nextPtr;
+	bigBlocks.nextPtr = bigBlockPtr;
+	bigBlockPtr->prevPtr = &bigBlocks;
+	bigBlockPtr->nextPtr->prevPtr = bigBlockPtr;
+
+	overPtr = (union overhead *) (bigBlockPtr + 1);
+	overPtr->overMagic0 = overPtr->overMagic1 = MAGIC;
+	overPtr->bucketIndex = 0xff;
+#ifdef MSTATS
+	numMallocs[NBUCKETS]++;
+#endif
+
+#ifndef NDEBUG
+	/*
+	 * Record allocated size of block and bound space with magic numbers.
+	 */
+
+	overPtr->realBlockSize = (numBytes + RSLOP - 1) & ~(RSLOP - 1);
+	overPtr->rangeCheckMagic = RMAGIC;
+	BLOCK_END(overPtr) = RMAGIC;
+#endif
+
+	Tcl_MutexUnlock(allocMutexPtr);
+	return (void *)(overPtr+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.
+     */
+
+    amount = MINBLOCK;		/* size of first bucket */
+    bucket = MINBLOCK >> 4;
+
+    while (numBytes + OVERHEAD > amount) {
+	amount <<= 1;
+	if (amount == 0) {
+	    Tcl_MutexUnlock(allocMutexPtr);
+	    return NULL;
+	}
+	bucket++;
+    }
+    ASSERT(bucket < NBUCKETS);
+
+    /*
+     * If nothing in hash bucket right now, request more memory from the
+     * system.
+     */
+
+    if ((overPtr = nextf[bucket]) == NULL) {
+	MoreCore(bucket);
+	if ((overPtr = nextf[bucket]) == NULL) {
+	    Tcl_MutexUnlock(allocMutexPtr);
+	    return NULL;
+	}
+    }
+
+    /*
+     * Remove from linked list
+     */
+
+    nextf[bucket] = overPtr->next;
+    overPtr->overMagic0 = overPtr->overMagic1 = MAGIC;
+    overPtr->bucketIndex = (unsigned char) bucket;
+
+#ifdef MSTATS
+    numMallocs[bucket]++;
+#endif
+
+#ifndef NDEBUG
+    /*
+     * Record allocated size of block and bound space with magic numbers.
+     */
+
+    overPtr->realBlockSize = (numBytes + RSLOP - 1) & ~(RSLOP - 1);
+    overPtr->rangeCheckMagic = RMAGIC;
+    BLOCK_END(overPtr) = RMAGIC;
+#endif
+
+    Tcl_MutexUnlock(allocMutexPtr);
+    return ((char *)(overPtr + 1));
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * MoreCore --
+ *
+ *	Allocate more memory to the indicated bucket.
+ *
+ *	Assumes Mutex is already held.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Attempts to get more memory from the system.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+MoreCore(
+    int bucket)			/* What bucket to allocat to. */
+{
+    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.
+     */
+
+    size = 1 << (bucket + 3);
+    ASSERT(size > 0);
+
+    amount = MAXMALLOC;
+    numBlocks = amount / size;
+    ASSERT(numBlocks*size == amount);
+
+    blockPtr = (struct block *) TclpSysAlloc((unsigned)
+	    (sizeof(struct block) + amount), 1);
+    /* no more room! */
+    if (blockPtr == NULL) {
+	return;
+    }
+    blockPtr->nextPtr = blockList;
+    blockList = blockPtr;
+
+    overPtr = (union overhead *) (blockPtr + 1);
+
+    /*
+     * Add new memory allocated to that on free list for this hash bucket.
+     */
+
+    nextf[bucket] = overPtr;
+    while (--numBlocks > 0) {
+	overPtr->next = (union overhead *)((caddr_t)overPtr + size);
+	overPtr = (union overhead *)((caddr_t)overPtr + size);
+    }
+    overPtr->next = NULL;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclpFree --
+ *
+ *	Free memory.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+void
+TclpFree(
+    char *oldPtr)		/* Pointer to memory to free. */
+{
+    register long size;
+    register union overhead *overPtr;
+    struct block *bigBlockPtr;
+
+    if (oldPtr == NULL) {
+	return;
+    }
+
+    Tcl_MutexLock(allocMutexPtr);
+    overPtr = (union overhead *)((caddr_t)oldPtr - sizeof(union overhead));
+
+    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(overPtr->rangeCheckMagic == RMAGIC);
+    RANGE_ASSERT(BLOCK_END(overPtr) == RMAGIC);
+    size = overPtr->bucketIndex;
+    if (size == 0xff) {
+#ifdef MSTATS
+	numMallocs[NBUCKETS]--;
+#endif
+
+	bigBlockPtr = (struct block *) overPtr - 1;
+	bigBlockPtr->prevPtr->nextPtr = bigBlockPtr->nextPtr;
+	bigBlockPtr->nextPtr->prevPtr = bigBlockPtr->prevPtr;
+	TclpSysFree(bigBlockPtr);
+
+	Tcl_MutexUnlock(allocMutexPtr);
+	return;
+    }
+    ASSERT(size < NBUCKETS);
+    overPtr->next = nextf[size];	/* also clobbers overMagic */
+    nextf[size] = overPtr;
+
+#ifdef MSTATS
+    numMallocs[size]--;
+#endif
+
+    Tcl_MutexUnlock(allocMutexPtr);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclpRealloc --
+ *
+ *	Reallocate memory.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+char *
+TclpRealloc(
+    char *oldPtr,		/* Pointer to alloced block. */
+    unsigned int numBytes)	/* New size of memory. */
+{
+    int i;
+    union overhead *overPtr;
+    struct block *bigBlockPtr;
+    int expensive;
+    unsigned long maxSize;
+
+    if (oldPtr == NULL) {
+	return TclpAlloc(numBytes);
+    }
+
+    Tcl_MutexLock(allocMutexPtr);
+
+    overPtr = (union overhead *)((caddr_t)oldPtr - sizeof(union overhead));
+
+    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(overPtr->rangeCheckMagic == RMAGIC);
+    RANGE_ASSERT(BLOCK_END(overPtr) == RMAGIC);
+    i = overPtr->bucketIndex;
+
+    /*
+     * If the block isn't in a bin, just realloc it.
+     */
+
+    if (i == 0xff) {
+	struct block *prevPtr, *nextPtr;
+	bigBlockPtr = (struct block *) overPtr - 1;
+	prevPtr = bigBlockPtr->prevPtr;
+	nextPtr = bigBlockPtr->nextPtr;
+	bigBlockPtr = (struct block *) TclpSysRealloc(bigBlockPtr,
+		sizeof(struct block) + OVERHEAD + numBytes);
+	if (bigBlockPtr == NULL) {
+	    Tcl_MutexUnlock(allocMutexPtr);
+	    return NULL;
+	}
+
+	if (prevPtr->nextPtr != bigBlockPtr) {
+	    /*
+	     * If the block has moved, splice the new block into the list
+	     * where the old block used to be.
+	     */
+
+	    prevPtr->nextPtr = bigBlockPtr;
+	    nextPtr->prevPtr = bigBlockPtr;
+	}
+
+	overPtr = (union overhead *) (bigBlockPtr + 1);
+
+#ifdef MSTATS
+	numMallocs[NBUCKETS]++;
+#endif
+
+#ifndef NDEBUG
+	/*
+	 * Record allocated size of block and update magic number bounds.
+	 */
+
+	overPtr->realBlockSize = (numBytes + RSLOP - 1) & ~(RSLOP - 1);
+	BLOCK_END(overPtr) = RMAGIC;
+#endif
+
+	Tcl_MutexUnlock(allocMutexPtr);
+	return (char *)(overPtr+1);
+    }
+    maxSize = 1 << (i+3);
+    expensive = 0;
+    if (numBytes+OVERHEAD > maxSize) {
+	expensive = 1;
+    } else if (i>0 && numBytes+OVERHEAD < maxSize/2) {
+	expensive = 1;
+    }
+
+    if (expensive) {
+	void *newPtr;
+
+	Tcl_MutexUnlock(allocMutexPtr);
+
+	newPtr = TclpAlloc(numBytes);
+	if (newPtr == NULL) {
+	    return NULL;
+	}
+	maxSize -= OVERHEAD;
+	if (maxSize < numBytes) {
+	    numBytes = maxSize;
+	}
+	memcpy(newPtr, oldPtr, (size_t) numBytes);
+	TclpFree(oldPtr);
+	return newPtr;
+    }
+
+    /*
+     * Ok, we don't have to copy, it fits as-is
+     */
+
+#ifndef NDEBUG
+    overPtr->realBlockSize = (numBytes + RSLOP - 1) & ~(RSLOP - 1);
+    BLOCK_END(overPtr) = RMAGIC;
+#endif
+
+    Tcl_MutexUnlock(allocMutexPtr);
+    return(oldPtr);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * 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(
+    char *s)			/* Where to write info. */
+{
+    register int i, j;
+    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, overPtr=nextf[i]; overPtr; overPtr=overPtr->next, j++) {
+	    fprintf(stderr, " %d", j);
+	}
+	totalFree += j * (1 << (i + 3));
+    }
+
+    fprintf(stderr, "\nused:\t");
+    for (i = 0; i < NBUCKETS; i++) {
+	fprintf(stderr, " %d", numMallocs[i]);
+	totalUsed += numMallocs[i] * (1 << (i + 3));
+    }
+
+    fprintf(stderr, "\n\tTotal small in use: %d, total free: %d\n",
+	    totalUsed, totalFree);
+    fprintf(stderr, "\n\tNumber of big (>%d) blocks in use: %d\n",
+	    MAXMALLOC, numMallocs[NBUCKETS]);
+
+    Tcl_MutexUnlock(allocMutexPtr);
+}
+#endif
+
+#else	/* !USE_TCLALLOC */
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclpAlloc --
+ *
+ *	Allocate more memory.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+char *
+TclpAlloc(
+    unsigned int numBytes)	/* Number of bytes to allocate. */
+{
+    return (char *) malloc(numBytes);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclpFree --
+ *
+ *	Free memory.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+void
+TclpFree(
+    char *oldPtr)		/* Pointer to memory to free. */
+{
+    free(oldPtr);
+    return;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclpRealloc --
+ *
+ *	Reallocate memory.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+char *
+TclpRealloc(
+    char *oldPtr,		/* Pointer to alloced block. */
+    unsigned int numBytes)	/* New size of memory. */
+{
+    return (char *) realloc(oldPtr, numBytes);
+}
+
+#endif /* !USE_TCLALLOC */
+#endif /* !TCL_THREADS */
+
+/*
+ * Local Variables:
+ * mode: c
+ * c-basic-offset: 4
+ * fill-column: 78
+ * End:
+ */