1/*
2 * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_LICENSE_HEADER_START@
5 *
6 * "Portions Copyright (c) 1999 Apple Computer, Inc.  All Rights
7 * Reserved.  This file contains Original Code and/or Modifications of
8 * Original Code as defined in and that are subject to the Apple Public
9 * Source License Version 1.0 (the 'License').  You may not use this file
10 * except in compliance with the License.  Please obtain a copy of the
11 * License at http://www.apple.com/publicsource and read it before using
12 * this file.
13 *
14 * The Original Code and all software distributed under the License are
15 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
16 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
17 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
19 * License for the specific language governing rights and limitations
20 * under the License."
21 *
22 * @APPLE_LICENSE_HEADER_END@
23 */
24/*  searchp  --  search through pathlist for file
25 *
26 *  Usage:  p = searchp (path,file,fullname,func);
27 *	char *p, *path, *file, *fullname;
28 *	int (*func)();
29 *
30 *  Searchp will parse "path", a list of pathnames separated
31 *  by colons, prepending each pathname to "file".  The resulting
32 *  filename will be passed to "func", a function provided by the
33 *  user.  This function must return zero if the search is
34 *  successful (i.e. ended), and non-zero if the search must
35 *  continue.  If the function returns zero (success), then
36 *  searching stops, the full filename is placed into "fullname",
37 *  and searchp returns 0.  If the pathnames are all unsuccessfully
38 *  examined, then searchp returns -1.
39 *  If "file" begins with a slash, it is assumed to be an
40 *  absolute pathname and the "path" list is not used.  Note
41 *  that this rule is used by Bell's cc also; whereas Bell's
42 *  sh uses the rule that any filename which CONTAINS a slash
43 *  is assumed to be absolute.  The execlp and execvp procedures
44 *  also use this latter rule.  In my opinion, this is bogosity.
45 *
46 *  HISTORY
47 * 01-Apr-86  Rudy Nedved (ern) at Carnegie-Mellon University
48 *	4.1BSD system ignores trailing slashes. 4.2BSD does not.
49 *	Therefore don't add a seperating slash if there is a null
50 *	filename.
51 *
52 * 23-Oct-82  Steven Shafer (sas) at Carnegie-Mellon University
53 *	Fixed two bugs: (1) calling function as "func" instead of
54 *	"(*func)", (2) omitting trailing null name implied by trailing
55 *	colon in path.  Latter bug fixed by introducing "lastchar" and
56 *	changing final loop test to look for "*lastchar" instead of
57 *	"*nextpath".
58 *
59 * 20-Nov-79  Steven Shafer (sas) at Carnegie-Mellon University
60 *	Created for VAX.  If you're thinking of using this, you probably
61 *	should look at openp() and fopenp() (or the "want..." routines)
62 *	instead.
63 *
64 */
65#include "config.h"
66
67int
68searchp(const char *spath, char *file, char *fullname, int (*func)(char *))
69{
70	const char *nextpath, *nextchar, *lastchar;
71	char *fname;
72	int failure;
73
74	nextpath = ((*file == '/') ? "" : spath);
75	do {
76		fname = fullname;
77		nextchar = nextpath;
78		while (*nextchar && (*nextchar != ':'))
79			*fname++ = *nextchar++;
80		if (nextchar != nextpath && *file) *fname++ = '/';
81		lastchar = nextchar;
82		nextpath = ((*nextchar) ? nextchar + 1 : nextchar);
83		nextchar = file;	/* append file */
84		while (*nextchar)  *fname++ = *nextchar++;
85		*fname = '\0';
86		failure = (*func) (fullname);
87	}
88	while (failure && (*lastchar));
89	return (failure ? -1 : 0);
90}
91