/tags/rel-1-3-26/SWIG/Source/DOH/memory.c

  1/* ----------------------------------------------------------------------------- 
  2 * memory.c
  3 *
  4 *     This file implements all of DOH's memory management including allocation
  5 *     of objects and checking of objects.
  6 * 
  7 * Author(s) : David Beazley (beazley@cs.uchicago.edu)
  8 *
  9 * Copyright (C) 1999-2000.  The University of Chicago
 10 * See the file LICENSE for information on usage and redistribution.	
 11 * ----------------------------------------------------------------------------- */
 12
 13char cvsroot_memory_c[] = "$Header$";
 14
 15#include "dohint.h"
 16
 17#ifndef DOH_POOL_SIZE
 18#define DOH_POOL_SIZE         16384
 19#endif
 20
 21static int   PoolSize = DOH_POOL_SIZE;
 22
 23DOH    *DohNone = 0;    /* The DOH None object */
 24
 25typedef struct pool {
 26  DohBase       *ptr;            /* Start of pool */
 27  int            len;            /* Length of pool */
 28  int            blen;           /* Byte length of pool */
 29  int            current;        /* Current position for next allocation */
 30  char*          pbeg;           /* Beg of pool */
 31  char*          pend;           /* End of pool */
 32  struct  pool  *next;           /* Next pool */
 33} Pool;
 34
 35static DohBase  *FreeList = 0;          /* List of free objects */
 36static Pool    *Pools = 0;
 37static int      pools_initialized = 0;
 38
 39/* ----------------------------------------------------------------------
 40 * CreatePool() - Create a new memory pool 
 41 * ---------------------------------------------------------------------- */
 42
 43static void
 44CreatePool() {
 45  Pool *p = 0;
 46  p = (Pool *) DohMalloc(sizeof(Pool));
 47  assert(p);
 48  p->ptr = (DohBase *) DohMalloc(sizeof(DohBase)*PoolSize);
 49  assert(p->ptr);
 50  memset(p->ptr,0,sizeof(DohBase)*PoolSize);
 51  p->len = PoolSize;
 52  p->blen = PoolSize*sizeof(DohBase);
 53  p->current = 0;
 54  p->pbeg = ((char *)p->ptr);
 55  p->pend = p->pbeg + p->blen;
 56  p->next = Pools;
 57  Pools = p;
 58}
 59
 60/* ----------------------------------------------------------------------
 61 * InitPools() - Initialize the memory allocator
 62 * ---------------------------------------------------------------------- */
 63
 64static void 
 65InitPools() {
 66  if (pools_initialized) return;
 67  CreatePool();                       /* Create initial pool */
 68  pools_initialized = 1;
 69  DohNone = NewVoid(0,0);             /* Create the None object */
 70  DohIntern(DohNone);
 71}
 72
 73/* ----------------------------------------------------------------------
 74 * DohCheck()
 75 *
 76 * Returns 1 if an arbitrary pointer is a DOH object.
 77 * ---------------------------------------------------------------------- */
 78
 79int 
 80DohCheck(const DOH *ptr) {
 81  register Pool *p = Pools;
 82  register char *cptr = (char *) ptr;
 83  while (p) {
 84    if ((cptr >= p->pbeg) && (cptr < p->pend)) return 1;
 85    /*
 86    pptr = (char *) p->ptr;
 87    if ((cptr >= pptr) && (cptr < (pptr+(p->current*sizeof(DohBase))))) return 1; */
 88    p = p->next;
 89  }
 90  return 0;
 91}
 92
 93/* -----------------------------------------------------------------------------
 94 * DohIntern()
 95 * ----------------------------------------------------------------------------- */
 96
 97void
 98DohIntern(DOH *obj) {
 99  DohBase *b = (DohBase *) obj;
100  b->flag_intern = 1;
101}
102
103/* ----------------------------------------------------------------------
104 * DohObjMalloc()
105 *
106 * Allocate memory for a new object.
107 * ---------------------------------------------------------------------- */
108
109DOH *
110DohObjMalloc(DohObjInfo *type, void *data) {
111  DohBase *obj;
112  if (!pools_initialized) InitPools();
113  if (FreeList) {
114    obj = FreeList;
115    FreeList = (DohBase *) obj->data;
116  } else {
117    while (Pools->current == Pools->len) {
118      PoolSize *= 2;
119      CreatePool();
120    }
121    obj = Pools->ptr + Pools->current;
122    Pools->current++;
123  }
124  obj->type = type;
125  obj->data = data;
126  obj->meta = 0;
127  obj->refcount = 1;
128  obj->flag_intern = 0;
129  obj->flag_marked = 0;
130  obj->flag_user = 0;
131  obj->flag_usermark = 0;
132  return (DOH *) obj;
133}
134
135/* ----------------------------------------------------------------------
136 * DohObjFree() - Free a DOH object
137 * ---------------------------------------------------------------------- */
138
139void 
140DohObjFree(DOH *ptr) {
141  DohBase  *b, *meta;
142  b = (DohBase *) ptr;
143  if (b->flag_intern) return;
144  meta = (DohBase *)b->meta;
145  b->data = (void *) FreeList;
146  b->meta = 0;
147  b->type = 0;
148  FreeList = b;
149  if (meta) {
150    Delete(meta);
151  }
152}
153
154/* ----------------------------------------------------------------------
155 * DohMemoryDebug()
156 *
157 * Display memory usage statistics
158 * ---------------------------------------------------------------------- */
159
160void
161DohMemoryDebug(void) {
162  extern DohObjInfo DohStringType;
163  extern DohObjInfo DohListType;
164  extern DohObjInfo DohHashType;
165
166  Pool *p;
167  int   totsize = 0;
168  int   totused = 0;
169  int   totfree = 0;
170
171  int   numstring = 0;
172  int   numlist   = 0;
173  int   numhash   = 0;
174
175  printf("Memory statistics:\n\n");
176  printf("Pools:\n");
177  
178  p = Pools;
179  while(p) {
180    /* Calculate number of used, free items */
181    int i;
182    int nused = 0, nfree = 0;
183    for (i = 0; i < p->len; i++) {
184      if (p->ptr[i].refcount <= 0) nfree++;
185      else {
186	nused++;
187	if (p->ptr[i].type == &DohStringType) numstring++;
188	else if (p->ptr[i].type == &DohListType) numlist++;
189	else if (p->ptr[i].type == &DohHashType) numhash++;
190      }
191    }
192    printf("    Pool %8p: size = %10d. used = %10d. free = %10d\n", (void *)p, p->len, nused, nfree);
193    totsize += p->len;
194    totused+= nused;
195    totfree+= nfree;
196    p = p->next;
197  }
198  printf("\n    Total:          size = %10d, used = %10d, free = %10d\n", totsize, totused, totfree);
199
200  printf("\nObject types\n");
201  printf("    Strings   : %d\n", numstring);
202  printf("    Lists     : %d\n", numlist);
203  printf("    Hashes    : %d\n", numhash);
204
205#if 0
206  p = Pools;
207  while(p) {
208    int i;
209    for (i = 0; i < p->len; i++) {
210      if (p->ptr[i].refcount > 0) {
211	if (p->ptr[i].type == &DohStringType) {
212	  Printf(stdout,"%s\n", p->ptr+i);
213	}
214      }
215    }
216    p = p->next;
217  }
218#endif
219
220}