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commit daa858ef278ad136afcb62d7f625b491ffbd5fa3
parent ea169d20835aa7d2a42641decc5b5d802047afca
Author: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date:   Tue, 16 Sep 1997 16:25:38 -0300

String table (keep all strings handled by Lua)

Diffstat:

Alstring.c | 186+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++


Alstring.h | 21+++++++++++++++++++++


Dtree.c | 211-------------------------------------------------------------------------------


Dtree.h | 38--------------------------------------


4 files changed, 207 insertions(+), 249 deletions(-)

diff --git a/lstring.c b/lstring.c
@@ -0,0 +1,186 @@
+/*
+** $Id: lstring.c,v 1.1 1997/08/14 20:23:30 roberto Exp $
+** String table (keep all strings handled by Lua)
+** See Copyright Notice in lua.h
+*/
+
+
+#include <string.h>
+
+#include "lmem.h"
+#include "lobject.h"
+#include "lstring.h"
+#include "lua.h"
+
+
+#define NUM_HASHS  61
+
+typedef struct {
+  int size;
+  int nuse;  /* number of elements (including EMPTYs) */
+  TaggedString **hash;
+} stringtable;
+
+
+static stringtable string_root[NUM_HASHS] = {
+{0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL},
+{0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL},
+{0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL},
+{0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL},
+{0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL},
+{0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL},
+{0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL},
+{0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL},
+{0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL},
+{0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL},
+{0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL},
+{0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL}, {0, 0, NULL},
+{0, 0, NULL}
+};
+
+
+static TaggedString EMPTY = {LUA_T_STRING, {0}, {{NOT_USED, NOT_USED}}, 2, {0}};
+
+
+
+static unsigned long hash (char *s, int tag)
+{
+  unsigned long h;
+  if (tag != LUA_T_STRING)
+    h = (unsigned long)s;
+  else {
+    h = 0;
+    while (*s)
+      h = ((h<<5)-h)^(unsigned char)*(s++);
+  }
+  return h;
+}
+
+
+static void grow (stringtable *tb)
+{
+  int newsize = luaO_redimension(tb->size);
+  TaggedString **newhash = luaM_newvector(newsize, TaggedString *);
+  int i;
+  for (i=0; i<newsize; i++)
+    newhash[i] = NULL;
+  /* rehash */
+  tb->nuse = 0;
+  for (i=0; i<tb->size; i++) {
+    if (tb->hash[i] != NULL && tb->hash[i] != &EMPTY) {
+      int h = tb->hash[i]->uu.hash%newsize;
+      while (newhash[h])
+        h = (h+1)%newsize;
+      newhash[h] = tb->hash[i];
+      tb->nuse++;
+    }
+  }
+  luaM_free(tb->hash);
+  tb->size = newsize;
+  tb->hash = newhash;
+}
+
+
+static TaggedString *newone(char *buff, int tag, unsigned long h)
+{
+  TaggedString *ts;
+  if (tag == LUA_T_STRING) {
+    ts = (TaggedString *)luaM_malloc(sizeof(TaggedString)+strlen(buff));
+    strcpy(ts->str, buff);
+    ts->u.s.varindex = ts->u.s.constindex = NOT_USED;
+    ts->tag = LUA_T_STRING;
+  }
+  else {
+    ts = (TaggedString *)luaM_malloc(sizeof(TaggedString));
+    ts->u.v = buff;
+    ts->tag = tag == LUA_ANYTAG ? 0 : tag;
+  }
+  ts->marked = 0;
+  ts->uu.hash = h;
+  return ts;
+}
+
+static TaggedString *insert (char *buff, int tag, stringtable *tb)
+{
+  TaggedString *ts;
+  unsigned long h = hash(buff, tag);
+  int i;
+  int j = -1;
+  if ((long)tb->nuse*3 >= (long)tb->size*2)
+    grow(tb);
+  i = h%tb->size;
+  while ((ts = tb->hash[i]) != NULL)
+  {
+    if (ts == &EMPTY)
+      j = i;
+    else if ((ts->tag == LUA_T_STRING) ?
+              (tag == LUA_T_STRING && (strcmp(buff, ts->str) == 0)) :
+              ((tag == ts->tag || tag == LUA_ANYTAG) && buff == ts->u.v))
+      return ts;
+    i = (i+1)%tb->size;
+  }
+  /* not found */
+  ++luaO_nentities;
+  if (j != -1)  /* is there an EMPTY space? */
+    i = j;
+  else
+    tb->nuse++;
+  ts = tb->hash[i] = newone(buff, tag, h);
+  return ts;
+}
+
+TaggedString *luaS_createudata (void *udata, int tag)
+{
+  return insert(udata, tag, &string_root[(unsigned)udata%NUM_HASHS]);
+}
+
+TaggedString *luaS_new (char *str)
+{
+  return insert(str, LUA_T_STRING, &string_root[(unsigned)str[0]%NUM_HASHS]);
+}
+
+TaggedString *luaS_newfixedstring (char *str)
+{
+  TaggedString *ts = luaS_new(str);
+  if (ts->marked == 0)
+    ts->marked = 2;  /* avoid GC */
+  return ts;
+}
+
+
+void luaS_free (TaggedString *l)
+{
+  while (l) {
+    TaggedString *next = l->uu.next;
+    luaM_free(l);
+    l = next;
+  }
+}
+
+
+/*
+** Garbage collection function.
+*/
+TaggedString *luaS_collector (void)
+{
+  TaggedString *frees = NULL;
+  int i;
+  for (i=0; i<NUM_HASHS; i++) {
+    stringtable *tb = &string_root[i];
+    int j;
+    for (j=0; j<tb->size; j++) {
+      TaggedString *t = tb->hash[j];
+      if (t == NULL) continue;
+      if (t->marked == 1)
+        t->marked = 0;
+      else if (!t->marked) {
+        t->uu.next = frees;
+        frees = t;
+        tb->hash[j] = &EMPTY;
+        --luaO_nentities;
+      }
+    }
+  }
+  return frees;
+}
+
diff --git a/lstring.h b/lstring.h
@@ -0,0 +1,21 @@
+/*
+** $Id: lstring.h,v 1.1 1997/08/14 20:23:40 roberto Exp roberto $
+** String table (keep all strings handled by Lua)
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lstring_h
+#define lstring_h
+
+
+#include "lobject.h"
+
+
+TaggedString *luaS_createudata (void *udata, int tag);
+TaggedString *luaS_collector (void);
+void luaS_free (TaggedString *l);
+void luaS_callIM (TaggedString *l);
+TaggedString *luaS_new (char *str);
+TaggedString *luaS_newfixedstring (char *str);
+
+#endif
diff --git a/tree.c b/tree.c
@@ -1,211 +0,0 @@
-/*
-** tree.c
-** TecCGraf - PUC-Rio
-*/
- 
-char *rcs_tree="$Id: tree.c,v 1.29 1997/07/30 22:00:50 roberto Exp roberto $";
-
-
-#include <string.h>
-
-#include "luamem.h"
-#include "lua.h"
-#include "tree.h"
-#include "lex.h"
-#include "hash.h"
-#include "table.h"
-#include "fallback.h"
-
-
-#define NUM_HASHS  61
-
-typedef struct {
-  int size;
-  int nuse;  /* number of elements (including EMPTYs) */
-  TaggedString **hash;
-} stringtable;
-
-static int initialized = 0;
-
-static stringtable string_root[NUM_HASHS];
-
-static TaggedString EMPTY = {LUA_T_STRING, NULL, {{NOT_USED, NOT_USED}},
-                             0, 2, {0}};
-
-
-static unsigned long hash (char *s, int tag)
-{
-  unsigned long h;
-  if (tag != LUA_T_STRING)
-    h = (unsigned long)s;
-  else {
-    h = 0;
-    while (*s)
-      h = ((h<<5)-h)^(unsigned char)*(s++);
-  }
-  return h;
-}
-
-
-static void luaI_inittree (void)
-{
-  int i;
-  for (i=0; i<NUM_HASHS; i++) {
-    string_root[i].size = 0;
-    string_root[i].nuse = 0;
-    string_root[i].hash = NULL;
-  }
-}
-
-
-static void initialize (void)
-{
-  initialized = 1;
-  luaI_inittree();
-  luaI_addReserved();
-  luaI_initsymbol();
-  luaI_initconstant();
-  luaI_initfallbacks();
-}
-
-
-static void grow (stringtable *tb)
-{
-  int newsize = luaI_redimension(tb->size);
-  TaggedString **newhash = newvector(newsize, TaggedString *);
-  int i;
-  for (i=0; i<newsize; i++)
-    newhash[i] = NULL;
-  /* rehash */
-  tb->nuse = 0;
-  for (i=0; i<tb->size; i++)
-    if (tb->hash[i] != NULL && tb->hash[i] != &EMPTY) {
-      int h = tb->hash[i]->hash%newsize;
-      while (newhash[h])
-        h = (h+1)%newsize;
-      newhash[h] = tb->hash[i];
-      tb->nuse++;
-    }
-  luaI_free(tb->hash); 
-  tb->size = newsize;
-  tb->hash = newhash;
-}
-
-
-static TaggedString *newone(char *buff, int tag, unsigned long h)
-{
-  TaggedString *ts;
-  if (tag == LUA_T_STRING) {
-    ts = (TaggedString *)luaI_malloc(sizeof(TaggedString)+strlen(buff));
-    strcpy(ts->str, buff);
-    ts->u.s.varindex = ts->u.s.constindex = NOT_USED;
-    ts->tag = LUA_T_STRING;
-  }
-  else {
-    ts = (TaggedString *)luaI_malloc(sizeof(TaggedString));
-    ts->u.v = buff;
-    ts->tag = tag == LUA_ANYTAG ? 0 : tag;
-  }
-  ts->marked = 0;
-  ts->hash = h;
-  return ts;
-}
-
-static TaggedString *insert (char *buff, int tag, stringtable *tb)
-{
-  TaggedString *ts;
-  unsigned long h = hash(buff, tag);
-  int i;
-  int j = -1;
-  if ((Long)tb->nuse*3 >= (Long)tb->size*2)
-  {
-    if (!initialized)
-      initialize();
-    grow(tb);
-  }
-  i = h%tb->size;
-  while ((ts = tb->hash[i]) != NULL)
-  {
-    if (ts == &EMPTY)
-      j = i;
-    else if ((ts->tag == LUA_T_STRING) ?
-              (tag == LUA_T_STRING && (strcmp(buff, ts->str) == 0)) :
-              ((tag == ts->tag || tag == LUA_ANYTAG) && buff == ts->u.v))
-      return ts;
-    i = (i+1)%tb->size;
-  }
-  /* not found */
-  lua_pack();
-  if (j != -1)  /* is there an EMPTY space? */
-    i = j;
-  else
-    tb->nuse++;
-  ts = tb->hash[i] = newone(buff, tag, h);
-  return ts;
-}
-
-TaggedString *luaI_createudata (void *udata, int tag)
-{
-  return insert(udata, tag, &string_root[(unsigned)udata%NUM_HASHS]);
-}
-
-TaggedString *luaI_createstring (char *str)
-{
-  return insert(str, LUA_T_STRING, &string_root[(unsigned)str[0]%NUM_HASHS]);
-}
-
-
-void luaI_strcallIM (TaggedString *l)
-{
-  TObject o;
-  ttype(&o) = LUA_T_USERDATA;
-  for (; l; l=l->next) {
-    tsvalue(&o) = l;
-    luaI_gcIM(&o);
-  }
-}
-
-
-void luaI_strfree (TaggedString *l)
-{
-  while (l) {
-    TaggedString *next = l->next;
-    luaI_free(l);
-    l = next;
-  }
-}
-
-
-/*
-** Garbage collection function.
-*/
-TaggedString *luaI_strcollector (long *acum)
-{
-  Long counter = 0;
-  TaggedString *frees = NULL;
-  int i;
-  for (i=0; i<NUM_HASHS; i++)
-  {
-    stringtable *tb = &string_root[i];
-    int j;
-    for (j=0; j<tb->size; j++)
-    {
-      TaggedString *t = tb->hash[j];
-      if (t != NULL && t->marked <= 1)
-      {
-        if (t->marked)
-          t->marked = 0;
-        else
-        {
-          t->next = frees;
-          frees = t;
-          tb->hash[j] = &EMPTY;
-          counter++;
-        }
-      }
-    }
-  }
-  *acum += counter;
-  return frees;
-}
-
diff --git a/tree.h b/tree.h
@@ -1,38 +0,0 @@
-/*
-** tree.h
-** TecCGraf - PUC-Rio
-** $Id: tree.h,v 1.18 1997/06/09 17:28:14 roberto Exp roberto $
-*/
-
-#ifndef tree_h
-#define tree_h
-
-#include "types.h"
-
-#define NOT_USED  0xFFFE
-
-
-typedef struct TaggedString
-{
-  int tag;  /* if != LUA_T_STRING, this is a userdata */
-  struct TaggedString *next;
-  union {
-    struct {
-      Word varindex;  /* != NOT_USED  if this is a symbol */
-      Word constindex;  /* hint to reuse constant indexes */
-    } s;
-    void *v;  /* if this is a userdata, here is its value */
-  } u;
-  unsigned long hash;  /* 0 if not initialized */
-  int marked;   /* for garbage collection; never collect (nor change) if > 1 */
-  char str[1];   /* \0 byte already reserved */
-} TaggedString;
- 
-
-TaggedString *luaI_createstring (char *str);
-TaggedString *luaI_createudata (void *udata, int tag);
-TaggedString *luaI_strcollector (long *cont);
-void luaI_strfree (TaggedString *l);
-void luaI_strcallIM (TaggedString *l);
-
-#endif