root/lib/pdf/xpdf/GHash.cc

DEFINITIONS

1. add
2. add
3. replace
4. replace
5. lookup
6. lookupInt
7. lookup
8. lookupInt
9. remove
10. removeInt
11. remove
12. removeInt
13. startIter
14. getNext
15. getNext
16. killIter
17. expand
18. find
19. find
20. hash
21. hash

//========================================================================
//
// GHash.cc
//
// Copyright 2001-2003 Glyph & Cog, LLC
//
//========================================================================

#include <aconf.h>

#ifdef USE_GCC_PRAGMAS
#pragma implementation
#endif

#include "gmem.h"
#include "GString.h"
#include "GHash.h"

//------------------------------------------------------------------------

struct GHashBucket {
  GString *key;
  union {
    void *p;
    int i;
  } val;
  GHashBucket *next;
};

struct GHashIter {
  int h;
  GHashBucket *p;
};

//------------------------------------------------------------------------

GHash::GHash(GBool deleteKeysA) {
  int h;

  deleteKeys = deleteKeysA;
  size = 7;
  tab = (GHashBucket **)gmallocn(size, sizeof(GHashBucket *));
  for (h = 0; h < size; ++h) {
    tab[h] = NULL;
  }
  len = 0;
}

GHash::~GHash() {
  GHashBucket *p;
  int h;

  for (h = 0; h < size; ++h) {
    while (tab[h]) {
      p = tab[h];
      tab[h] = p->next;
      if (deleteKeys) {
        delete p->key;
      }
      delete p;
    }
  }
  gfree(tab);
}

void GHash::add(GString *key, void *val) {
  GHashBucket *p;
  int h;

  // expand the table if necessary
  if (len >= size) {
    expand();
  }

  // add the new symbol
  p = new GHashBucket;
  p->key = key;
  p->val.p = val;
  h = hash(key);
  p->next = tab[h];
  tab[h] = p;
  ++len;
}

void GHash::add(GString *key, int val) {
  GHashBucket *p;
  int h;

  // expand the table if necessary
  if (len >= size) {
    expand();
  }

  // add the new symbol
  p = new GHashBucket;
  p->key = key;
  p->val.i = val;
  h = hash(key);
  p->next = tab[h];
  tab[h] = p;
  ++len;
}

void GHash::replace(GString *key, void *val) {
  GHashBucket *p;
  int h;

  if ((p = find(key, &h))) {
    p->val.p = val;
    delete key;
  } else {
    add(key, val);
  }
}

void GHash::replace(GString *key, int val) {
  GHashBucket *p;
  int h;

  if ((p = find(key, &h))) {
    p->val.i = val;
    delete key;
  } else {
    add(key, val);
  }
}

void *GHash::lookup(GString *key) {
  GHashBucket *p;
  int h;

  if (!(p = find(key, &h))) {
    return NULL;
  }
  return p->val.p;
}

int GHash::lookupInt(GString *key) {
  GHashBucket *p;
  int h;

  if (!(p = find(key, &h))) {
    return 0;
  }
  return p->val.i;
}

void *GHash::lookup(char *key) {
  GHashBucket *p;
  int h;

  if (!(p = find(key, &h))) {
    return NULL;
  }
  return p->val.p;
}

int GHash::lookupInt(char *key) {
  GHashBucket *p;
  int h;

  if (!(p = find(key, &h))) {
    return 0;
  }
  return p->val.i;
}

void *GHash::remove(GString *key) {
  GHashBucket *p;
  GHashBucket **q;
  void *val;
  int h;

  if (!(p = find(key, &h))) {
    return NULL;
  }
  q = &tab[h];
  while (*q != p) {
    q = &((*q)->next);
  }
  *q = p->next;
  if (deleteKeys) {
    delete p->key;
  }
  val = p->val.p;
  delete p;
  --len;
  return val;
}

int GHash::removeInt(GString *key) {
  GHashBucket *p;
  GHashBucket **q;
  int val;
  int h;

  if (!(p = find(key, &h))) {
    return 0;
  }
  q = &tab[h];
  while (*q != p) {
    q = &((*q)->next);
  }
  *q = p->next;
  if (deleteKeys) {
    delete p->key;
  }
  val = p->val.i;
  delete p;
  --len;
  return val;
}

void *GHash::remove(char *key) {
  GHashBucket *p;
  GHashBucket **q;
  void *val;
  int h;

  if (!(p = find(key, &h))) {
    return NULL;
  }
  q = &tab[h];
  while (*q != p) {
    q = &((*q)->next);
  }
  *q = p->next;
  if (deleteKeys) {
    delete p->key;
  }
  val = p->val.p;
  delete p;
  --len;
  return val;
}

int GHash::removeInt(char *key) {
  GHashBucket *p;
  GHashBucket **q;
  int val;
  int h;

  if (!(p = find(key, &h))) {
    return 0;
  }
  q = &tab[h];
  while (*q != p) {
    q = &((*q)->next);
  }
  *q = p->next;
  if (deleteKeys) {
    delete p->key;
  }
  val = p->val.i;
  delete p;
  --len;
  return val;
}

void GHash::startIter(GHashIter **iter) {
  *iter = new GHashIter;
  (*iter)->h = -1;
  (*iter)->p = NULL;
}

GBool GHash::getNext(GHashIter **iter, GString **key, void **val) {
  if (!*iter) {
    return gFalse;
  }
  if ((*iter)->p) {
    (*iter)->p = (*iter)->p->next;
  }
  while (!(*iter)->p) {
    if (++(*iter)->h == size) {
      delete *iter;
      *iter = NULL;
      return gFalse;
    }
    (*iter)->p = tab[(*iter)->h];
  }
  *key = (*iter)->p->key;
  *val = (*iter)->p->val.p;
  return gTrue;
}

GBool GHash::getNext(GHashIter **iter, GString **key, int *val) {
  if (!*iter) {
    return gFalse;
  }
  if ((*iter)->p) {
    (*iter)->p = (*iter)->p->next;
  }
  while (!(*iter)->p) {
    if (++(*iter)->h == size) {
      delete *iter;
      *iter = NULL;
      return gFalse;
    }
    (*iter)->p = tab[(*iter)->h];
  }
  *key = (*iter)->p->key;
  *val = (*iter)->p->val.i;
  return gTrue;
}

void GHash::killIter(GHashIter **iter) {
  delete *iter;
  *iter = NULL;
}

void GHash::expand() {
  GHashBucket **oldTab;
  GHashBucket *p;
  int oldSize, h, i;

  oldSize = size;
  oldTab = tab;
  size = 2*size + 1;
  tab = (GHashBucket **)gmallocn(size, sizeof(GHashBucket *));
  for (h = 0; h < size; ++h) {
    tab[h] = NULL;
  }
  for (i = 0; i < oldSize; ++i) {
    while (oldTab[i]) {
      p = oldTab[i];
      oldTab[i] = oldTab[i]->next;
      h = hash(p->key);
      p->next = tab[h];
      tab[h] = p;
    }
  }
  gfree(oldTab);
}

GHashBucket *GHash::find(GString *key, int *h) {
  GHashBucket *p;

  *h = hash(key);
  for (p = tab[*h]; p; p = p->next) {
    if (!p->key->cmp(key)) {
      return p;
    }
  }
  return NULL;
}

GHashBucket *GHash::find(char *key, int *h) {
  GHashBucket *p;

  *h = hash(key);
  for (p = tab[*h]; p; p = p->next) {
    if (!p->key->cmp(key)) {
      return p;
    }
  }
  return NULL;
}

int GHash::hash(GString *key) {
  char *p;
  unsigned int h;
  int i;

  h = 0;
  for (p = key->getCString(), i = 0; i < key->getLength(); ++p, ++i) {
    h = 17 * h + (int)(*p & 0xff);
  }
  return (int)(h % size);
}

int GHash::hash(char *key) {
  char *p;
  unsigned int h;

  h = 0;
  for (p = key; *p; ++p) {
    h = 17 * h + (int)(*p & 0xff);
  }
  return (int)(h % size);
}