1/****************************************************************************
2 * Copyright (c) 1998-2007,2008 Free Software Foundation, Inc.              *
3 *                                                                          *
4 * Permission is hereby granted, free of charge, to any person obtaining a  *
5 * copy of this software and associated documentation files (the            *
6 * "Software"), to deal in the Software without restriction, including      *
7 * without limitation the rights to use, copy, modify, merge, publish,      *
8 * distribute, distribute with modifications, sublicense, and/or sell       *
9 * copies of the Software, and to permit persons to whom the Software is    *
10 * furnished to do so, subject to the following conditions:                 *
11 *                                                                          *
12 * The above copyright notice and this permission notice shall be included  *
13 * in all copies or substantial portions of the Software.                   *
14 *                                                                          *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
16 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
18 * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
19 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
20 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
21 * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
22 *                                                                          *
23 * Except as contained in this notice, the name(s) of the above copyright   *
24 * holders shall not be used in advertising or otherwise to promote the     *
25 * sale, use or other dealings in this Software without prior written       *
26 * authorization.                                                           *
27 ****************************************************************************/
28
29/****************************************************************************
30 *  Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995               *
31 *     and: Eric S. Raymond <esr@snark.thyrsus.com>                         *
32 *     and: Thomas E. Dickey                        1996-on                 *
33 ****************************************************************************/
34
35/*
36 *	comp_hash.c --- Routines to deal with the hashtable of capability
37 *			names.
38 *
39 */
40
41#define USE_TERMLIB 1
42#include <curses.priv.h>
43
44#include <tic.h>
45#include <hashsize.h>
46
47#ifdef MAIN_PROGRAM
48#include <ctype.h>
49#undef  DEBUG
50#define DEBUG(level, params)	/*nothing */
51#endif
52
53MODULE_ID("$Id: comp_hash.c,v 1.36 2008/08/16 17:06:53 tom Exp $")
54
55static int hash_function(const char *);
56
57/*
58 *	_nc_make_hash_table()
59 *
60 *	Takes the entries in table[] and hashes them into hash_table[]
61 *	by name.  There are CAPTABSIZE entries in table[] and HASHTABSIZE
62 *	slots in hash_table[].
63 *
64 */
65
66#ifdef MAIN_PROGRAM
67
68#undef MODULE_ID
69#define MODULE_ID(id)		/*nothing */
70#include <tinfo/doalloc.c>
71
72static void
73_nc_make_hash_table(struct name_table_entry *table,
74		    short *hash_table)
75{
76    short i;
77    int hashvalue;
78    int collisions = 0;
79
80    for (i = 0; i < HASHTABSIZE; i++) {
81	hash_table[i] = -1;
82    }
83    for (i = 0; i < CAPTABSIZE; i++) {
84	hashvalue = hash_function(table[i].nte_name);
85
86	if (hash_table[hashvalue] >= 0)
87	    collisions++;
88
89	if (hash_table[hashvalue] != 0)
90	    table[i].nte_link = hash_table[hashvalue];
91	hash_table[hashvalue] = i;
92    }
93
94    DEBUG(4, ("Hash table complete: %d collisions out of %d entries",
95	      collisions, CAPTABSIZE));
96}
97#endif
98
99/*
100 *	int hash_function(string)
101 *
102 *	Computes the hashing function on the given string.
103 *
104 *	The current hash function is the sum of each consectutive pair
105 *	of characters, taken as two-byte integers, mod HASHTABSIZE.
106 *
107 */
108
109static int
110hash_function(const char *string)
111{
112    long sum = 0;
113
114    DEBUG(9, ("hashing %s", string));
115    while (*string) {
116	sum += (long) (*string + (*(string + 1) << 8));
117	string++;
118    }
119
120    DEBUG(9, ("sum is %ld", sum));
121    return (int) (sum % HASHTABSIZE);
122}
123
124/*
125 *	struct name_table_entry *
126 *	find_entry(string)
127 *
128 *	Finds the entry for the given string in the hash table if present.
129 *	Returns a pointer to the entry in the table or 0 if not found.
130 *
131 */
132
133#ifndef MAIN_PROGRAM
134NCURSES_EXPORT(struct name_table_entry const *)
135_nc_find_entry(const char *string,
136	       const short *hash_table)
137{
138    int hashvalue;
139    struct name_table_entry const *ptr = 0;
140    struct name_table_entry const *real_table;
141
142    hashvalue = hash_function(string);
143
144    if (hash_table[hashvalue] >= 0) {
145	real_table = _nc_get_table(hash_table != _nc_get_hash_table(FALSE));
146	ptr = real_table + hash_table[hashvalue];
147	while (strcmp(ptr->nte_name, string) != 0) {
148	    if (ptr->nte_link < 0)
149		return 0;
150	    ptr = real_table + (ptr->nte_link + hash_table[HASHTABSIZE]);
151	}
152    }
153
154    return (ptr);
155}
156
157/*
158 *	struct name_table_entry *
159 *	find_type_entry(string, type, table)
160 *
161 *	Finds the first entry for the given name with the given type in the
162 *	given table if present (as distinct from find_entry, which finds the
163 *	the last entry regardless of type).  You can use this if you detect
164 *	a name clash.  It's slower, though.  Returns a pointer to the entry
165 *	in the table or 0 if not found.
166 */
167
168NCURSES_EXPORT(struct name_table_entry const *)
169_nc_find_type_entry(const char *string,
170		    int type,
171		    const struct name_table_entry *table)
172{
173    struct name_table_entry const *ptr;
174
175    for (ptr = table; ptr < table + CAPTABSIZE; ptr++) {
176	if (ptr->nte_type == type && strcmp(string, ptr->nte_name) == 0)
177	    return (ptr);
178    }
179
180    return ((struct name_table_entry *) NULL);
181}
182#endif
183
184#ifdef MAIN_PROGRAM
185/*
186 * This filter reads from standard input a list of tab-delimited columns,
187 * (e.g., from Caps.filtered) computes the hash-value of a specified column and
188 * writes the hashed tables to standard output.
189 *
190 * By compiling the hash table at build time, we're able to make the entire
191 * set of terminfo and termcap tables readonly (and also provide some runtime
192 * performance enhancement).
193 */
194
195#define MAX_COLUMNS BUFSIZ	/* this _has_ to be worst-case */
196
197static char **
198parse_columns(char *buffer)
199{
200    static char **list;
201
202    int col = 0;
203
204    if (list == 0 && (list = typeCalloc(char *, MAX_COLUMNS)) == 0)
205	  return (0);
206
207    if (*buffer != '#') {
208	while (*buffer != '\0') {
209	    char *s;
210	    for (s = buffer; (*s != '\0') && !isspace(UChar(*s)); s++)
211		/*EMPTY */ ;
212	    if (s != buffer) {
213		char mark = *s;
214		*s = '\0';
215		if ((s - buffer) > 1
216		    && (*buffer == '"')
217		    && (s[-1] == '"')) {	/* strip the quotes */
218		    assert(s > buffer + 1);
219		    s[-1] = '\0';
220		    buffer++;
221		}
222		list[col] = buffer;
223		col++;
224		if (mark == '\0')
225		    break;
226		while (*++s && isspace(UChar(*s)))
227		    /*EMPTY */ ;
228		buffer = s;
229	    } else
230		break;
231	}
232    }
233    return col ? list : 0;
234}
235
236int
237main(int argc, char **argv)
238{
239    struct name_table_entry *name_table = typeCalloc(struct
240						     name_table_entry, CAPTABSIZE);
241    short *hash_table = typeCalloc(short, HASHTABSIZE);
242    const char *root_name = "";
243    int column = 0;
244    int bigstring = 0;
245    int n;
246    char buffer[BUFSIZ];
247
248    static const char *typenames[] =
249    {"BOOLEAN", "NUMBER", "STRING"};
250
251    short BoolCount = 0;
252    short NumCount = 0;
253    short StrCount = 0;
254
255    /* The first argument is the column-number (starting with 0).
256     * The second is the root name of the tables to generate.
257     */
258    if (argc <= 3
259	|| (column = atoi(argv[1])) <= 0
260	|| (column >= MAX_COLUMNS)
261	|| *(root_name = argv[2]) == 0
262	|| (bigstring = atoi(argv[3])) < 0
263	|| name_table == 0
264	|| hash_table == 0) {
265	fprintf(stderr, "usage: make_hash column root_name bigstring\n");
266	exit(EXIT_FAILURE);
267    }
268
269    /*
270     * Read the table into our arrays.
271     */
272    for (n = 0; (n < CAPTABSIZE) && fgets(buffer, BUFSIZ, stdin);) {
273	char **list, *nlp = strchr(buffer, '\n');
274	if (nlp)
275	    *nlp = '\0';
276	list = parse_columns(buffer);
277	if (list == 0)		/* blank or comment */
278	    continue;
279	name_table[n].nte_link = -1;	/* end-of-hash */
280	name_table[n].nte_name = strdup(list[column]);
281	if (!strcmp(list[2], "bool")) {
282	    name_table[n].nte_type = BOOLEAN;
283	    name_table[n].nte_index = BoolCount++;
284	} else if (!strcmp(list[2], "num")) {
285	    name_table[n].nte_type = NUMBER;
286	    name_table[n].nte_index = NumCount++;
287	} else if (!strcmp(list[2], "str")) {
288	    name_table[n].nte_type = STRING;
289	    name_table[n].nte_index = StrCount++;
290	} else {
291	    fprintf(stderr, "Unknown type: %s\n", list[2]);
292	    exit(EXIT_FAILURE);
293	}
294	n++;
295    }
296    _nc_make_hash_table(name_table, hash_table);
297
298    /*
299     * Write the compiled tables to standard output
300     */
301    if (bigstring) {
302	int len = 0;
303	int nxt;
304
305	printf("static const char %s_names_text[] = \\\n", root_name);
306	for (n = 0; n < CAPTABSIZE; n++) {
307	    nxt = (int) strlen(name_table[n].nte_name) + 5;
308	    if (nxt + len > 72) {
309		printf("\\\n");
310		len = 0;
311	    }
312	    printf("\"%s\\0\" ", name_table[n].nte_name);
313	    len += nxt;
314	}
315	printf(";\n\n");
316
317	len = 0;
318	printf("static name_table_data const %s_names_data[] =\n",
319	       root_name);
320	printf("{\n");
321	for (n = 0; n < CAPTABSIZE; n++) {
322	    printf("\t{ %15d,\t%10s,\t%3d, %3d }%c\n",
323		   len,
324		   typenames[name_table[n].nte_type],
325		   name_table[n].nte_index,
326		   name_table[n].nte_link,
327		   n < CAPTABSIZE - 1 ? ',' : ' ');
328	    len += (int) strlen(name_table[n].nte_name) + 1;
329	}
330	printf("};\n\n");
331	printf("static struct name_table_entry *_nc_%s_table = 0;\n\n", root_name);
332    } else {
333
334	printf("static struct name_table_entry %s _nc_%s_table[] =\n",
335	       bigstring ? "" : "const",
336	       root_name);
337	printf("{\n");
338	for (n = 0; n < CAPTABSIZE; n++) {
339	    sprintf(buffer, "\"%s\"",
340		    name_table[n].nte_name);
341	    printf("\t{ %15s,\t%10s,\t%3d, %3d }%c\n",
342		   buffer,
343		   typenames[name_table[n].nte_type],
344		   name_table[n].nte_index,
345		   name_table[n].nte_link,
346		   n < CAPTABSIZE - 1 ? ',' : ' ');
347	}
348	printf("};\n\n");
349    }
350
351    printf("static const short _nc_%s_hash_table[%d] =\n",
352	   root_name,
353	   HASHTABSIZE + 1);
354    printf("{\n");
355    for (n = 0; n < HASHTABSIZE; n++) {
356	printf("\t%3d,\n", hash_table[n]);
357    }
358    printf("\t0\t/* base-of-table */\n");
359    printf("};\n\n");
360
361    printf("#if (BOOLCOUNT!=%d)||(NUMCOUNT!=%d)||(STRCOUNT!=%d)\n",
362	   BoolCount, NumCount, StrCount);
363    printf("#error\t--> term.h and comp_captab.c disagree about the <--\n");
364    printf("#error\t--> numbers of booleans, numbers and/or strings <--\n");
365    printf("#endif\n\n");
366
367    free(hash_table);
368    return EXIT_SUCCESS;
369}
370#endif
371