tw.spell.c revision 316958 
1/* $Header: /p/tcsh/cvsroot/tcsh/tw.spell.c,v 3.21 2006/03/02 18:46:45 christos Exp $ */
2/*
3 * tw.spell.c: Spell check words
4 */
5/*-
6 * Copyright (c) 1980, 1991 The Regents of the University of California.
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 3. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33#include "sh.h"
34
35RCSID("$tcsh: tw.spell.c,v 3.21 2006/03/02 18:46:45 christos Exp $")
36
37#include "tw.h"
38
39/* spell_me : return corrrectly spelled filename.  From K&P spname */
40int
41spell_me(struct Strbuf *oldname, int looking, Char *pat, eChar suf)
42{
43    struct Strbuf guess = Strbuf_INIT, newname = Strbuf_INIT;
44    const Char *old = oldname->s;
45    size_t ws;
46    int    foundslash = 0;
47    int     retval;
48
49    cleanup_push(&guess, Strbuf_cleanup);
50    cleanup_push(&newname, Strbuf_cleanup);
51    for (;;) {
52	while (*old == '/') {	/* skip '/' */
53	    Strbuf_append1(&newname, *old++);
54	    foundslash = 1;
55	}
56	/* do not try to correct spelling of single letter words */
57	if (*old != '\0' && old[1] == '\0')
58	    Strbuf_append1(&newname, *old++);
59	Strbuf_terminate(&newname);
60	if (*old == '\0') {
61	    retval = (StrQcmp(oldname->s, newname.s) != 0);
62	    cleanup_ignore(&newname);
63	    xfree(oldname->s);
64	    *oldname = newname; /* shove it back. */
65	    cleanup_until(&guess);
66	    return retval;
67	}
68	guess.len = 0;		/* start at beginning of buf */
69	Strbuf_append(&guess, newname.s); /* add current dir if any */
70	ws = guess.len;
71	for (; *old != '/' && *old != '\0'; old++)/* add current file name */
72	    Strbuf_append1(&guess, *old);
73	Strbuf_terminate(&guess);
74
75	/*
76	 * Don't tell t_search we're looking for cmd if no '/' in the name so
77	 * far but there are later - or it will look for *all* commands
78	 */
79	/* (*should* say "looking for directory" whenever '/' is next...) */
80	retval = t_search(&guess, SPELL,
81			  looking == TW_COMMAND && (foundslash || *old != '/') ?
82			  TW_COMMAND : looking, 1, pat, suf);
83	if (retval >= 4 || retval < 0) {
84	    cleanup_until(&guess);
85	    return -1;		/* hopeless */
86	}
87	Strbuf_append(&newname, guess.s + ws);
88    }
89/*NOTREACHED*/
90#ifdef notdef
91    return (0);			/* lint on the vax under mtXinu complains! */
92#endif
93}
94
95#define EQ(s,t)	(StrQcmp(s,t) == 0)
96
97/*
98 * spdist() is taken from Kernighan & Pike,
99 *  _The_UNIX_Programming_Environment_
100 * and adapted somewhat to correspond better to psychological reality.
101 * (Note the changes to the return values)
102 *
103 * According to Pollock and Zamora, CACM April 1984 (V. 27, No. 4),
104 * page 363, the correct order for this is:
105 * OMISSION = TRANSPOSITION > INSERTION > SUBSTITUTION
106 * thus, it was exactly backwards in the old version. -- PWP
107 */
108
109int
110spdist(const Char *s, const Char *t)
111{
112    for (; (*s & TRIM) == (*t & TRIM); t++, s++)
113	if (*t == '\0')
114	    return 0;		/* exact match */
115    if (*s) {
116	if (*t) {
117	    if (s[1] && t[1] && (*s & TRIM) == (t[1] & TRIM) &&
118		(*t & TRIM) == (s[1] & TRIM) && EQ(s + 2, t + 2))
119		return 1;	/* transposition */
120	    if (EQ(s + 1, t + 1))
121		return 3;	/* 1 char mismatch */
122	}
123	if (EQ(s + 1, t))
124	    return 2;		/* extra character */
125    }
126    if (*t && EQ(s, t + 1))
127	return 1;		/* missing character */
128    return 4;
129}
130
131int
132spdir(struct Strbuf *extended_name, const Char *tilded_dir, const Char *item,
133      Char *name)
134{
135    Char *path, *s, oldch;
136    char *p;
137
138    if (ISDOT(item) || ISDOTDOT(item))
139	return 0;
140
141    for (s = name; *s != 0 && (*s & TRIM) == (*item & TRIM); s++, item++)
142	continue;
143    if (*s == 0 || s[1] == 0 || *item != 0)
144	return 0;
145
146    path = xmalloc((Strlen(tilded_dir) + Strlen(name) + 1) * sizeof (*path));
147    (void) Strcpy(path, tilded_dir);
148    oldch = *s;
149    *s = '/';
150    Strcat(path, name);
151    p = short2str(path);
152    xfree(path);
153    if (access(p, F_OK) == 0) {
154	extended_name->len = 0;
155	Strbuf_append(extended_name, name);
156	Strbuf_terminate(extended_name);
157	/* FIXME: *s = oldch? */
158	return 1;
159    }
160    *s = oldch;
161    return 0;
162}
163