coreutils/lib/argmatch.c
1992-10-31 20:42:48 +00:00

84 lines
2.4 KiB
C

/* argmatch.c -- find a match for a string in an array
Copyright (C) 1990 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
/* Written by David MacKenzie <djm@ai.mit.edu> */
#include <stdio.h>
#ifdef STDC_HEADERS
#include <string.h>
#endif
extern char *program_name;
/* If ARG is an unambiguous match for an element of the
null-terminated array OPTLIST, return the index in OPTLIST
of the matched element, else -1 if it does not match any element
or -2 if it is ambiguous (is a prefix of more than one element). */
int
argmatch (arg, optlist)
char *arg;
char **optlist;
{
int i; /* Temporary index in OPTLIST. */
int arglen; /* Length of ARG. */
int matchind = -1; /* Index of first nonexact match. */
int ambiguous = 0; /* If nonzero, multiple nonexact match(es). */
arglen = strlen (arg);
/* Test all elements for either exact match or abbreviated matches. */
for (i = 0; optlist[i]; i++)
{
if (!strncmp (optlist[i], arg, arglen))
{
if (strlen (optlist[i]) == arglen)
/* Exact match found. */
return i;
else if (matchind == -1)
/* First nonexact match found. */
matchind = i;
else
/* Second nonexact match found. */
ambiguous = 1;
}
}
if (ambiguous)
return -2;
else
return matchind;
}
/* Error reporting for argmatch.
KIND is a description of the type of entity that was being matched.
VALUE is the invalid value that was given.
PROBLEM is the return value from argmatch. */
void
invalid_arg (kind, value, problem)
char *kind;
char *value;
int problem;
{
fprintf (stderr, "%s: ", program_name);
if (problem == -1)
fprintf (stderr, "invalid");
else /* Assume -2. */
fprintf (stderr, "ambiguous");
fprintf (stderr, " %s `%s'\n", kind, value);
}