xref: /plan9/sys/src/ape/cmd/patch/argmatch.c (revision 0b459c2cb92b7c9d88818e9a2f72e678e5bc4553)
1*0b459c2cSDavid du Colombier /* argmatch.c -- find a match for a string in an array
2*0b459c2cSDavid du Colombier    Copyright (C) 1990, 1997 Free Software Foundation, Inc.
3*0b459c2cSDavid du Colombier 
4*0b459c2cSDavid du Colombier    This program is free software; you can redistribute it and/or modify
5*0b459c2cSDavid du Colombier    it under the terms of the GNU General Public License as published by
6*0b459c2cSDavid du Colombier    the Free Software Foundation; either version 2, or (at your option)
7*0b459c2cSDavid du Colombier    any later version.
8*0b459c2cSDavid du Colombier 
9*0b459c2cSDavid du Colombier    This program is distributed in the hope that it will be useful,
10*0b459c2cSDavid du Colombier    but WITHOUT ANY WARRANTY; without even the implied warranty of
11*0b459c2cSDavid du Colombier    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12*0b459c2cSDavid du Colombier    GNU General Public License for more details.
13*0b459c2cSDavid du Colombier 
14*0b459c2cSDavid du Colombier    You should have received a copy of the GNU General Public License
15*0b459c2cSDavid du Colombier    along with this program; see the file COPYING.
16*0b459c2cSDavid du Colombier    If not, write to the Free Software Foundation,
17*0b459c2cSDavid du Colombier    59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
18*0b459c2cSDavid du Colombier 
19*0b459c2cSDavid du Colombier /* Written by David MacKenzie <djm@gnu.ai.mit.edu> */
20*0b459c2cSDavid du Colombier 
21*0b459c2cSDavid du Colombier #if HAVE_CONFIG_H
22*0b459c2cSDavid du Colombier # include <config.h>
23*0b459c2cSDavid du Colombier #endif
24*0b459c2cSDavid du Colombier 
25*0b459c2cSDavid du Colombier #include <argmatch.h>
26*0b459c2cSDavid du Colombier 
27*0b459c2cSDavid du Colombier #include <sys/types.h>
28*0b459c2cSDavid du Colombier 
29*0b459c2cSDavid du Colombier #include <stdio.h>
30*0b459c2cSDavid du Colombier #if HAVE_STRING_H
31*0b459c2cSDavid du Colombier # include <string.h>
32*0b459c2cSDavid du Colombier #else
33*0b459c2cSDavid du Colombier # include <strings.h>
34*0b459c2cSDavid du Colombier #endif
35*0b459c2cSDavid du Colombier 
36*0b459c2cSDavid du Colombier /* If ARG is an unambiguous match for an element of the
37*0b459c2cSDavid du Colombier    null-terminated array OPTLIST, return the index in OPTLIST
38*0b459c2cSDavid du Colombier    of the matched element, else -1 if it does not match any element
39*0b459c2cSDavid du Colombier    or -2 if it is ambiguous (is a prefix of more than one element).  */
40*0b459c2cSDavid du Colombier 
41*0b459c2cSDavid du Colombier int
argmatch(arg,optlist)42*0b459c2cSDavid du Colombier argmatch (arg, optlist)
43*0b459c2cSDavid du Colombier      const char *arg;
44*0b459c2cSDavid du Colombier      const char *const *optlist;
45*0b459c2cSDavid du Colombier {
46*0b459c2cSDavid du Colombier   int i;			/* Temporary index in OPTLIST.  */
47*0b459c2cSDavid du Colombier   size_t arglen;		/* Length of ARG.  */
48*0b459c2cSDavid du Colombier   int matchind = -1;		/* Index of first nonexact match.  */
49*0b459c2cSDavid du Colombier   int ambiguous = 0;		/* If nonzero, multiple nonexact match(es).  */
50*0b459c2cSDavid du Colombier 
51*0b459c2cSDavid du Colombier   arglen = strlen (arg);
52*0b459c2cSDavid du Colombier 
53*0b459c2cSDavid du Colombier   /* Test all elements for either exact match or abbreviated matches.  */
54*0b459c2cSDavid du Colombier   for (i = 0; optlist[i]; i++)
55*0b459c2cSDavid du Colombier     {
56*0b459c2cSDavid du Colombier       if (!strncmp (optlist[i], arg, arglen))
57*0b459c2cSDavid du Colombier 	{
58*0b459c2cSDavid du Colombier 	  if (strlen (optlist[i]) == arglen)
59*0b459c2cSDavid du Colombier 	    /* Exact match found.  */
60*0b459c2cSDavid du Colombier 	    return i;
61*0b459c2cSDavid du Colombier 	  else if (matchind == -1)
62*0b459c2cSDavid du Colombier 	    /* First nonexact match found.  */
63*0b459c2cSDavid du Colombier 	    matchind = i;
64*0b459c2cSDavid du Colombier 	  else
65*0b459c2cSDavid du Colombier 	    /* Second nonexact match found.  */
66*0b459c2cSDavid du Colombier 	    ambiguous = 1;
67*0b459c2cSDavid du Colombier 	}
68*0b459c2cSDavid du Colombier     }
69*0b459c2cSDavid du Colombier   if (ambiguous)
70*0b459c2cSDavid du Colombier     return -2;
71*0b459c2cSDavid du Colombier   else
72*0b459c2cSDavid du Colombier     return matchind;
73*0b459c2cSDavid du Colombier }
74*0b459c2cSDavid du Colombier 
75*0b459c2cSDavid du Colombier /* Error reporting for argmatch.
76*0b459c2cSDavid du Colombier    KIND is a description of the type of entity that was being matched.
77*0b459c2cSDavid du Colombier    VALUE is the invalid value that was given.
78*0b459c2cSDavid du Colombier    PROBLEM is the return value from argmatch.  */
79*0b459c2cSDavid du Colombier 
80*0b459c2cSDavid du Colombier void
invalid_arg(kind,value,problem)81*0b459c2cSDavid du Colombier invalid_arg (kind, value, problem)
82*0b459c2cSDavid du Colombier      const char *kind;
83*0b459c2cSDavid du Colombier      const char *value;
84*0b459c2cSDavid du Colombier      int problem;
85*0b459c2cSDavid du Colombier {
86*0b459c2cSDavid du Colombier   fprintf (stderr, "%s: ", program_name);
87*0b459c2cSDavid du Colombier   if (problem == -1)
88*0b459c2cSDavid du Colombier     fprintf (stderr, "invalid");
89*0b459c2cSDavid du Colombier   else				/* Assume -2.  */
90*0b459c2cSDavid du Colombier     fprintf (stderr, "ambiguous");
91*0b459c2cSDavid du Colombier   fprintf (stderr, " %s `%s'\n", kind, value);
92*0b459c2cSDavid du Colombier }
93