OpenBSD-4.6/lib/libcurses/tinfo/comp_hash.c
/* $OpenBSD: comp_hash.c,v 1.7 2007/03/20 03:40:06 tedu Exp $ */
/****************************************************************************
* Copyright (c) 1998 Free Software Foundation, Inc. *
* *
* Permission is hereby granted, free of charge, to any person obtaining a *
* copy of this software and associated documentation files (the *
* "Software"), to deal in the Software without restriction, including *
* without limitation the rights to use, copy, modify, merge, publish, *
* distribute, distribute with modifications, sublicense, and/or sell *
* copies of the Software, and to permit persons to whom the Software is *
* furnished to do so, subject to the following conditions: *
* *
* The above copyright notice and this permission notice shall be included *
* in all copies or substantial portions of the Software. *
* *
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS *
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF *
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. *
* IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, *
* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR *
* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR *
* THE USE OR OTHER DEALINGS IN THE SOFTWARE. *
* *
* Except as contained in this notice, the name(s) of the above copyright *
* holders shall not be used in advertising or otherwise to promote the *
* sale, use or other dealings in this Software without prior written *
* authorization. *
****************************************************************************/
/****************************************************************************
* Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995 *
* and: Eric S. Raymond <esr@snark.thyrsus.com> *
****************************************************************************/
/*
* comp_hash.c --- Routines to deal with the hashtable of capability
* names.
*
*/
#include <curses.priv.h>
#include <tic.h>
#include <hashsize.h>
#ifdef MAIN_PROGRAM
#include <ctype.h>
#undef DEBUG
#define DEBUG(level, params) /*nothing*/
#endif
MODULE_ID("$From: comp_hash.c,v 1.21 1999/06/26 21:25:11 tom Exp $")
static int hash_function(const char *);
/*
* _nc_make_hash_table()
*
* Takes the entries in table[] and hashes them into hash_table[]
* by name. There are CAPTABSIZE entries in table[] and HASHTABSIZE
* slots in hash_table[].
*
*/
#ifdef MAIN_PROGRAM
#undef MODULE_ID
#define MODULE_ID(id) /*nothing*/
#include <tinfo/doalloc.c>
static void _nc_make_hash_table(struct name_table_entry *table,
struct name_table_entry **hash_table)
{
int i;
int hashvalue;
int collisions = 0;
for (i = 0; i < CAPTABSIZE; i++) {
hashvalue = hash_function(table[i].nte_name);
if (hash_table[hashvalue] != (struct name_table_entry *) 0)
collisions++;
if (hash_table[hashvalue] != 0)
table[i].nte_link = (short)(hash_table[hashvalue] - table);
hash_table[hashvalue] = &table[i];
}
DEBUG(4, ("Hash table complete: %d collisions out of %d entries", collisions, CAPTABSIZE));
}
#endif
/*
* int hash_function(string)
*
* Computes the hashing function on the given string.
*
* The current hash function is the sum of each consectutive pair
* of characters, taken as two-byte integers, mod Hashtabsize.
*
*/
static
int
hash_function(const char *string)
{
long sum = 0;
DEBUG(9, ("hashing %s", string));
while (*string) {
sum += (long)(*string + (*(string + 1) << 8));
string++;
}
DEBUG(9, ("sum is %ld", sum));
return (int)(sum % HASHTABSIZE);
}
/*
* struct name_table_entry *
* find_entry(string)
*
* Finds the entry for the given string in the hash table if present.
* Returns a pointer to the entry in the table or 0 if not found.
*
*/
#ifndef MAIN_PROGRAM
struct name_table_entry const *
_nc_find_entry(const char *string, const struct name_table_entry *const *hash_table)
{
int hashvalue;
struct name_table_entry const *ptr;
hashvalue = hash_function(string);
if ((ptr = hash_table[hashvalue]) != 0) {
while (strcmp(ptr->nte_name, string) != 0) {
if (ptr->nte_link < 0)
return 0;
ptr = ptr->nte_link + hash_table[HASHTABSIZE];
}
}
return (ptr);
}
/*
* struct name_table_entry *
* find_type_entry(string, type, table)
*
* Finds the first entry for the given name with the given type in the
* given table if present (as distinct from find_entry, which finds the
* the last entry regardless of type). You can use this if you detect
* a name clash. It's slower, though. Returns a pointer to the entry
* in the table or 0 if not found.
*/
struct name_table_entry const *
_nc_find_type_entry(const char *string,
int type,
const struct name_table_entry *table)
{
struct name_table_entry const *ptr;
for (ptr = table; ptr < table + CAPTABSIZE; ptr++) {
if (ptr->nte_type == type && strcmp(string, ptr->nte_name) == 0)
return(ptr);
}
return ((struct name_table_entry *)NULL);
}
#endif
#ifdef MAIN_PROGRAM
/*
* This filter reads from standard input a list of tab-delimited columns,
* (e.g., from Caps.filtered) computes the hash-value of a specified column and
* writes the hashed tables to standard output.
*
* By compiling the hash table at build time, we're able to make the entire
* set of terminfo and termcap tables readonly (and also provide some runtime
* performance enhancement).
*/
#define MAX_COLUMNS BUFSIZ /* this _has_ to be worst-case */
static char **parse_columns(char *buffer)
{
static char **list;
int col = 0;
if (list == 0 && (list = typeCalloc(char *, MAX_COLUMNS)) == 0)
return(0);
if (*buffer != '#') {
while (*buffer != '\0') {
char *s;
for (s = buffer; (*s != '\0') && !isspace(*s); s++)
/*EMPTY*/;
if (s != buffer) {
char mark = *s;
*s = '\0';
if ((s - buffer) > 1
&& (*buffer == '"')
&& (s[-1] == '"')) { /* strip the quotes */
buffer++;
s[-1] = '\0';
}
list[col] = buffer;
col++;
if (mark == '\0')
break;
while (isspace(*++s))
/*EMPTY*/;
buffer = s;
} else
break;
}
}
return col ? list : 0;
}
int main(int argc, char **argv)
{
struct name_table_entry *name_table = typeCalloc(struct name_table_entry, CAPTABSIZE);
struct name_table_entry **hash_table = typeCalloc(struct name_table_entry *, HASHTABSIZE);
const char *root_name = "";
int column = 0;
int n;
char buffer[BUFSIZ];
static const char * typenames[] = { "BOOLEAN", "NUMBER", "STRING" };
short BoolCount = 0;
short NumCount = 0;
short StrCount = 0;
/* The first argument is the column-number (starting with 0).
* The second is the root name of the tables to generate.
*/
if (argc <= 2
|| (column = atoi(argv[1])) <= 0
|| (column >= MAX_COLUMNS)
|| *(root_name = argv[2]) == 0) {
fprintf(stderr, "usage: make_hash column root_name\n");
exit(EXIT_FAILURE);
}
/*
* Read the table into our arrays.
*/
for (n = 0; (n < CAPTABSIZE) && fgets(buffer, BUFSIZ, stdin); ) {
char **list, *nlp = strchr(buffer, '\n');
if (nlp)
*nlp = '\0';
list = parse_columns(buffer);
if (list == 0) /* blank or comment */
continue;
name_table[n].nte_link = -1; /* end-of-hash */
name_table[n].nte_name = strdup(list[column]);
if (!strcmp(list[2], "bool")) {
name_table[n].nte_type = BOOLEAN;
name_table[n].nte_index = BoolCount++;
} else if (!strcmp(list[2], "num")) {
name_table[n].nte_type = NUMBER;
name_table[n].nte_index = NumCount++;
} else if (!strcmp(list[2], "str")) {
name_table[n].nte_type = STRING;
name_table[n].nte_index = StrCount++;
} else {
fprintf(stderr, "Unknown type: %s\n", list[2]);
exit(EXIT_FAILURE);
}
n++;
}
_nc_make_hash_table(name_table, hash_table);
/*
* Write the compiled tables to standard output
*/
printf("static struct name_table_entry const _nc_%s_table[] =\n",
root_name);
printf("{\n");
for (n = 0; n < CAPTABSIZE; n++) {
snprintf(buffer, sizeof(buffer), "\"%s\"",
name_table[n].nte_name);
printf("\t{ %15s,\t%10s,\t%3d, %3d }%c\n",
buffer,
typenames[name_table[n].nte_type],
name_table[n].nte_index,
name_table[n].nte_link,
n < CAPTABSIZE - 1 ? ',' : ' ');
}
printf("};\n\n");
printf("const struct name_table_entry * const _nc_%s_hash_table[%d] =\n",
root_name,
HASHTABSIZE+1);
printf("{\n");
for (n = 0; n < HASHTABSIZE; n++) {
if (hash_table[n] != 0) {
snprintf(buffer, sizeof(buffer), "_nc_%s_table + %3ld",
root_name,
(long) (hash_table[n] - name_table));
} else {
buffer[0] = '0';
buffer[1] = '\0';
}
printf("\t%s,\n", buffer);
}
printf("\t_nc_%s_table\t/* base-of-table */\n", root_name);
printf("};\n\n");
printf("#if (BOOLCOUNT!=%d)||(NUMCOUNT!=%d)||(STRCOUNT!=%d)\n",
BoolCount, NumCount, StrCount);
printf("#error\t--> term.h and comp_captab.c disagree about the <--\n");
printf("#error\t--> numbers of booleans, numbers and/or strings <--\n");
printf("#endif\n\n");
return EXIT_SUCCESS;
}
#endif