xref: /freebsd/contrib/tcsh/tw.spell.c (revision d0a9cc17ba44cff547c673bd3086231a68b76370)
1 /*
2  * tw.spell.c: Spell check words
3  */
4 /*-
5  * Copyright (c) 1980, 1991 The Regents of the University of California.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 #include "sh.h"
33 #include "tw.h"
34 
35 /* spell_me : return corrrectly spelled filename.  From K&P spname */
36 int
37 spell_me(struct Strbuf *oldname, int looking, Char *pat, eChar suf)
38 {
39     struct Strbuf guess = Strbuf_INIT, newname = Strbuf_INIT;
40     const Char *old = oldname->s;
41     size_t ws;
42     int    foundslash = 0;
43     int     retval;
44 
45     cleanup_push(&guess, Strbuf_cleanup);
46     cleanup_push(&newname, Strbuf_cleanup);
47     for (;;) {
48 	while (*old == '/') {	/* skip '/' */
49 	    Strbuf_append1(&newname, *old++);
50 	    foundslash = 1;
51 	}
52 	/* do not try to correct spelling of single letter words */
53 	if (*old != '\0' && old[1] == '\0')
54 	    Strbuf_append1(&newname, *old++);
55 	Strbuf_terminate(&newname);
56 	if (*old == '\0') {
57 	    retval = (StrQcmp(oldname->s, newname.s) != 0);
58 	    cleanup_ignore(&newname);
59 	    xfree(oldname->s);
60 	    *oldname = newname; /* shove it back. */
61 	    cleanup_until(&guess);
62 	    return retval;
63 	}
64 	guess.len = 0;		/* start at beginning of buf */
65 	Strbuf_append(&guess, newname.s); /* add current dir if any */
66 	ws = guess.len;
67 	for (; *old != '/' && *old != '\0'; old++)/* add current file name */
68 	    Strbuf_append1(&guess, *old);
69 	Strbuf_terminate(&guess);
70 
71 	/*
72 	 * Don't tell t_search we're looking for cmd if no '/' in the name so
73 	 * far but there are later - or it will look for *all* commands
74 	 */
75 	/* (*should* say "looking for directory" whenever '/' is next...) */
76 	retval = t_search(&guess, SPELL,
77 			  looking == TW_COMMAND && (foundslash || *old != '/') ?
78 			  TW_COMMAND : looking, 1, pat, suf);
79 	if (retval >= 4 || retval < 0) {
80 	    cleanup_until(&guess);
81 	    return -1;		/* hopeless */
82 	}
83 	Strbuf_append(&newname, guess.s + ws);
84     }
85 /*NOTREACHED*/
86 #ifdef notdef
87     return (0);			/* lint on the vax under mtXinu complains! */
88 #endif
89 }
90 
91 #define EQ(s,t)	(StrQcmp(s,t) == 0)
92 
93 /*
94  * spdist() is taken from Kernighan & Pike,
95  *  _The_UNIX_Programming_Environment_
96  * and adapted somewhat to correspond better to psychological reality.
97  * (Note the changes to the return values)
98  *
99  * According to Pollock and Zamora, CACM April 1984 (V. 27, No. 4),
100  * page 363, the correct order for this is:
101  * OMISSION = TRANSPOSITION > INSERTION > SUBSTITUTION
102  * thus, it was exactly backwards in the old version. -- PWP
103  */
104 
105 int
106 spdist(const Char *s, const Char *t)
107 {
108     for (; (*s & TRIM) == (*t & TRIM); t++, s++)
109 	if (*t == '\0')
110 	    return 0;		/* exact match */
111     if (*s) {
112 	if (*t) {
113 	    if (s[1] && t[1] && (*s & TRIM) == (t[1] & TRIM) &&
114 		(*t & TRIM) == (s[1] & TRIM) && EQ(s + 2, t + 2))
115 		return 1;	/* transposition */
116 	    if (EQ(s + 1, t + 1))
117 		return 3;	/* 1 char mismatch */
118 	}
119 	if (EQ(s + 1, t))
120 	    return 2;		/* extra character */
121     }
122     if (*t && EQ(s, t + 1))
123 	return 1;		/* missing character */
124     return 4;
125 }
126 
127 int
128 spdir(struct Strbuf *extended_name, const Char *tilded_dir, const Char *item,
129       Char *name)
130 {
131     Char *path, *s, oldch;
132     char *p;
133 
134     if (ISDOT(item) || ISDOTDOT(item))
135 	return 0;
136 
137     for (s = name; *s != 0 && (*s & TRIM) == (*item & TRIM); s++, item++)
138 	continue;
139     if (*s == 0 || s[1] == 0 || *item != 0)
140 	return 0;
141 
142     path = xmalloc((Strlen(tilded_dir) + Strlen(name) + 1) * sizeof (*path));
143     (void) Strcpy(path, tilded_dir);
144     oldch = *s;
145     *s = '/';
146     Strcat(path, name);
147     p = short2str(path);
148     xfree(path);
149     if (access(p, F_OK) == 0) {
150 	extended_name->len = 0;
151 	Strbuf_append(extended_name, name);
152 	Strbuf_terminate(extended_name);
153 	/* FIXME: *s = oldch? */
154 	return 1;
155     }
156     *s = oldch;
157     return 0;
158 }
159