--- /dev/null
+/*
+ * hash.c
+ *
+ * $Id: hash.c,v 1.3 95/10/05 11:57:07 parrt Exp $
+ * $Revision: 1.3 $
+ *
+ * Manage hash tables.
+ *
+ * The following functions are visible:
+ *
+ * char *mystrdup(char *); Make space and copy string
+ * Entry **newHashTable(); Create and return initialized hash table
+ * Entry *hash_add(Entry **, char *, Entry *)
+ * Entry *hash_get(Entry **, char *)
+ *
+ * SOFTWARE RIGHTS
+ *
+ * We reserve no LEGAL rights to the Purdue Compiler Construction Tool
+ * Set (PCCTS) -- PCCTS is in the public domain. An individual or
+ * company may do whatever they wish with source code distributed with
+ * PCCTS or the code generated by PCCTS, including the incorporation of
+ * PCCTS, or its output, into commerical software.
+ *
+ * We encourage users to develop software with PCCTS. However, we do ask
+ * that credit is given to us for developing PCCTS. By "credit",
+ * we mean that if you incorporate our source code into one of your
+ * programs (commercial product, research project, or otherwise) that you
+ * acknowledge this fact somewhere in the documentation, research report,
+ * etc... If you like PCCTS and have developed a nice tool with the
+ * output, please mention that you developed it using PCCTS. In
+ * addition, we ask that this header remain intact in our source code.
+ * As long as these guidelines are kept, we expect to continue enhancing
+ * this system and expect to make other tools available as they are
+ * completed.
+ *
+ * ANTLR 1.33
+ * Terence Parr
+ * Parr Research Corporation
+ * with Purdue University and AHPCRC, University of Minnesota
+ * 1989-1995
+ */
+
+#include <stdio.h>
+#include "config.h"
+#ifdef __cplusplus
+#ifndef __STDC__
+#define __STDC__
+#endif
+#endif
+#include "hash.h"
+#ifdef __STDC__
+#include <stdlib.h>
+#else
+#ifdef VAXC
+#include <stdlib.h>
+#else
+#include <malloc.h>
+#endif
+#endif
+#include <string.h>
+
+#define StrSame 0
+
+#define fatal(err) \
+ {fprintf(stderr, "%s(%d):", __FILE__, __LINE__); \
+ fprintf(stderr, " %s\n", err); exit(PCCTS_EXIT_FAILURE);}
+#define require(expr, err) {if ( !(expr) ) fatal(err);}
+
+static unsigned size = HashTableSize;
+static char *strings = NULL;
+static char *strp;
+static unsigned strsize = StrTableSize;
+
+/* create the hash table and string table for terminals (string table only once) */
+Entry **
+#ifdef __STDC__
+newHashTable( void )
+#else
+newHashTable( )
+#endif
+{
+ Entry **table;
+
+ table = (Entry **) calloc(size, sizeof(Entry *));
+ require( table != NULL, "cannot allocate hash table");
+ if ( strings == NULL )
+ {
+ strings = (char *) calloc(strsize, sizeof(char));
+ require( strings != NULL, "cannot allocate string table");
+ strp = strings;
+ }
+ return table;
+}
+
+void
+#ifdef __STDC__
+killHashTable( Entry **table )
+#else
+killHashTable( table )
+Entry **table;
+#endif
+{
+ /* for now, just free table, forget entries */
+ free( table );
+}
+
+/* Given a table, add 'rec' with key 'key' (add to front of list). return ptr to entry */
+Entry *
+#ifdef __STDC__
+hash_add( Entry **table, char *key, Entry *rec )
+#else
+hash_add( table, key, rec )
+Entry **table;
+char *key;
+Entry *rec;
+#endif
+{
+ unsigned h=0;
+ char *p=key;
+ extern Entry *Globals;
+ require(table!=NULL && key!=NULL && rec!=NULL, "add: invalid addition");
+
+ Hash(p,h,size);
+ rec->next = table[h]; /* Add to singly-linked list */
+ table[h] = rec;
+ return rec;
+}
+
+/* Return ptr to 1st entry found in table under key (return NULL if none found) */
+Entry *
+#ifdef __STDC__
+hash_get( Entry **table, char *key )
+#else
+hash_get( table, key )
+Entry **table;
+char *key;
+#endif
+{
+ unsigned h=0;
+ char *p=key;
+ Entry *q;
+/* require(table!=NULL && key!=NULL, "get: invalid table and/or key");*/
+ if ( !(table!=NULL && key!=NULL) ) *((char *) 34) = 3;
+
+ Hash(p,h,size);
+ for (q = table[h]; q != NULL; q = q->next)
+ {
+ if ( strcmp(key, q->str) == StrSame ) return( q );
+ }
+ return( NULL );
+}
+
+#ifdef DEBUG_HASH
+void
+#ifdef __STDC__
+hashStat( Entry **table )
+#else
+hashStat( table )
+Entry **table;
+#endif
+{
+ static unsigned short count[20];
+ int i,n=0,low=0, hi=0;
+ Entry **p;
+ float avg=0.0;
+
+ for (i=0; i<20; i++) count[i] = 0;
+ for (p=table; p<&(table[size]); p++)
+ {
+ Entry *q = *p;
+ int len;
+
+ if ( q != NULL && low==0 ) low = p-table;
+ len = 0;
+ if ( q != NULL ) fprintf(stderr, "[%d]", p-table);
+ while ( q != NULL )
+ {
+ len++;
+ n++;
+ fprintf(stderr, " %s", q->str);
+ q = q->next;
+ if ( q == NULL ) fprintf(stderr, "\n");
+ }
+ count[len]++;
+ if ( *p != NULL ) hi = p-table;
+ }
+
+ fprintf(stderr, "Storing %d recs used %d hash positions out of %d\n",
+ n, size-count[0], size);
+ fprintf(stderr, "%f %% utilization\n",
+ ((float)(size-count[0]))/((float)size));
+ for (i=0; i<20; i++)
+ {
+ if ( count[i] != 0 )
+ {
+ avg += (((float)(i*count[i]))/((float)n)) * i;
+ fprintf(stderr, "Bucket len %d == %d (%f %% of recs)\n",
+ i, count[i], ((float)(i*count[i]))/((float)n));
+ }
+ }
+ fprintf(stderr, "Avg bucket length %f\n", avg);
+ fprintf(stderr, "Range of hash function: %d..%d\n", low, hi);
+}
+#endif
+
+/* Add a string to the string table and return a pointer to it.
+ * Bump the pointer into the string table to next avail position.
+ */
+char *
+#ifdef __STDC__
+mystrdup( char *s )
+#else
+mystrdup( s )
+char *s;
+#endif
+{
+ char *start=strp;
+ require(s!=NULL, "mystrdup: NULL string");
+
+ while ( *s != '\0' )
+ {
+ require( strp <= &(strings[strsize-2]),
+ "string table overflow\nIncrease StrTableSize in hash.h and recompile hash.c\n");
+ *strp++ = *s++;
+ }
+ *strp++ = '\0';
+
+ return( start );
+}
projects / pccts / blobdiff