xref: /onnv-gate/usr/src/tools/cscope-fast/compath.c (revision 0:68f95e015346)
1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * CDDL HEADER START
3*0Sstevel@tonic-gate  *
4*0Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
7*0Sstevel@tonic-gate  * with the License.
8*0Sstevel@tonic-gate  *
9*0Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate  * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate  * and limitations under the License.
13*0Sstevel@tonic-gate  *
14*0Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate  *
20*0Sstevel@tonic-gate  * CDDL HEADER END
21*0Sstevel@tonic-gate  */
22*0Sstevel@tonic-gate /*	Copyright (c) 1988 AT&T	*/
23*0Sstevel@tonic-gate /*	  All Rights Reserved  	*/
24*0Sstevel@tonic-gate 
25*0Sstevel@tonic-gate 
26*0Sstevel@tonic-gate /*
27*0Sstevel@tonic-gate  * Copyright (c) 1999 by Sun Microsystems, Inc.
28*0Sstevel@tonic-gate  * All rights reserved.
29*0Sstevel@tonic-gate  */
30*0Sstevel@tonic-gate 
31*0Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
32*0Sstevel@tonic-gate 
33*0Sstevel@tonic-gate /*
34*0Sstevel@tonic-gate  *	compath(pathname)
35*0Sstevel@tonic-gate  *
36*0Sstevel@tonic-gate  *	This compresses pathnames.  All strings of multiple slashes are
37*0Sstevel@tonic-gate  *	changed to a single slash.  All occurrences of "./" are removed.
38*0Sstevel@tonic-gate  *	Whenever possible, strings of "/.." are removed together with
39*0Sstevel@tonic-gate  *	the directory names that they follow.
40*0Sstevel@tonic-gate  *
41*0Sstevel@tonic-gate  *	WARNING: since pathname is altered by this function, it should
42*0Sstevel@tonic-gate  *		 be located in a temporary buffer. This avoids the problem
43*0Sstevel@tonic-gate  *		 of accidently changing strings obtained from makefiles
44*0Sstevel@tonic-gate  *		 and stored in global structures.
45*0Sstevel@tonic-gate  */
46*0Sstevel@tonic-gate 
47*0Sstevel@tonic-gate #include <string.h>
48*0Sstevel@tonic-gate 
49*0Sstevel@tonic-gate char *
compath(char * pathname)50*0Sstevel@tonic-gate compath(char *pathname)
51*0Sstevel@tonic-gate {
52*0Sstevel@tonic-gate 	char	*nextchar;
53*0Sstevel@tonic-gate 	char	*lastchar;
54*0Sstevel@tonic-gate 	char	*sofar;
55*0Sstevel@tonic-gate 	char	*pnend;
56*0Sstevel@tonic-gate 
57*0Sstevel@tonic-gate 	int	pnlen;
58*0Sstevel@tonic-gate 
59*0Sstevel@tonic-gate 		/*
60*0Sstevel@tonic-gate 		 *	do not change the path if it has no "/"
61*0Sstevel@tonic-gate 		 */
62*0Sstevel@tonic-gate 
63*0Sstevel@tonic-gate 	if (strchr(pathname, '/') == 0)
64*0Sstevel@tonic-gate 		return (pathname);
65*0Sstevel@tonic-gate 
66*0Sstevel@tonic-gate 		/*
67*0Sstevel@tonic-gate 		 *	find all strings consisting of more than one '/'
68*0Sstevel@tonic-gate 		 */
69*0Sstevel@tonic-gate 
70*0Sstevel@tonic-gate 	for (lastchar = pathname + 1; *lastchar != '\0'; lastchar++)
71*0Sstevel@tonic-gate 		if ((*lastchar == '/') && (*(lastchar - 1) == '/')) {
72*0Sstevel@tonic-gate 
73*0Sstevel@tonic-gate 			/*
74*0Sstevel@tonic-gate 			 *	find the character after the last slash
75*0Sstevel@tonic-gate 			 */
76*0Sstevel@tonic-gate 
77*0Sstevel@tonic-gate 			nextchar = lastchar;
78*0Sstevel@tonic-gate 			while (*++lastchar == '/') {
79*0Sstevel@tonic-gate 			}
80*0Sstevel@tonic-gate 
81*0Sstevel@tonic-gate 			/*
82*0Sstevel@tonic-gate 			 *	eliminate the extra slashes by copying
83*0Sstevel@tonic-gate 			 *	everything after the slashes over the slashes
84*0Sstevel@tonic-gate 			 */
85*0Sstevel@tonic-gate 
86*0Sstevel@tonic-gate 			sofar = nextchar;
87*0Sstevel@tonic-gate 			while ((*nextchar++ = *lastchar++) != '\0')
88*0Sstevel@tonic-gate 				;
89*0Sstevel@tonic-gate 			lastchar = sofar;
90*0Sstevel@tonic-gate 		}
91*0Sstevel@tonic-gate 
92*0Sstevel@tonic-gate 		/*
93*0Sstevel@tonic-gate 		 *	find all strings of "./"
94*0Sstevel@tonic-gate 		 */
95*0Sstevel@tonic-gate 
96*0Sstevel@tonic-gate 	for (lastchar = pathname + 1; *lastchar != '\0'; lastchar++)
97*0Sstevel@tonic-gate 		if ((*lastchar == '/') && (*(lastchar - 1) == '.') &&
98*0Sstevel@tonic-gate 		    ((lastchar - 1 == pathname) || (*(lastchar - 2) == '/'))) {
99*0Sstevel@tonic-gate 
100*0Sstevel@tonic-gate 			/*
101*0Sstevel@tonic-gate 			 *	copy everything after the "./" over the "./"
102*0Sstevel@tonic-gate 			 */
103*0Sstevel@tonic-gate 
104*0Sstevel@tonic-gate 			nextchar = lastchar - 1;
105*0Sstevel@tonic-gate 			sofar = nextchar;
106*0Sstevel@tonic-gate 			while ((*nextchar++ = *++lastchar) != '\0')
107*0Sstevel@tonic-gate 				;
108*0Sstevel@tonic-gate 			lastchar = sofar;
109*0Sstevel@tonic-gate 		}
110*0Sstevel@tonic-gate 
111*0Sstevel@tonic-gate 		/*
112*0Sstevel@tonic-gate 		 *	find each occurrence of "/.."
113*0Sstevel@tonic-gate 		 */
114*0Sstevel@tonic-gate 
115*0Sstevel@tonic-gate 	for (lastchar = pathname + 1; *lastchar != '\0'; lastchar++)
116*0Sstevel@tonic-gate 		if ((lastchar != pathname) && (*lastchar == '/') &&
117*0Sstevel@tonic-gate 		    (*(lastchar + 1) == '.') && (*(lastchar + 2) == '.') &&
118*0Sstevel@tonic-gate 		    ((*(lastchar + 3) == '/') || (*(lastchar + 3) == '\0'))) {
119*0Sstevel@tonic-gate 
120*0Sstevel@tonic-gate 			/*
121*0Sstevel@tonic-gate 			 *	find the directory name preceding the "/.."
122*0Sstevel@tonic-gate 			 */
123*0Sstevel@tonic-gate 
124*0Sstevel@tonic-gate 			nextchar = lastchar - 1;
125*0Sstevel@tonic-gate 			while ((nextchar != pathname) &&
126*0Sstevel@tonic-gate 			    (*(nextchar - 1) != '/'))
127*0Sstevel@tonic-gate 				--nextchar;
128*0Sstevel@tonic-gate 
129*0Sstevel@tonic-gate 			/*
130*0Sstevel@tonic-gate 			 *	make sure the preceding directory's name
131*0Sstevel@tonic-gate 			 *	is not "." or ".."
132*0Sstevel@tonic-gate 			 */
133*0Sstevel@tonic-gate 
134*0Sstevel@tonic-gate 			if ((*nextchar == '.') &&
135*0Sstevel@tonic-gate 			    (*(nextchar + 1) == '/') ||
136*0Sstevel@tonic-gate 			    ((*(nextchar + 1) == '.') &&
137*0Sstevel@tonic-gate 			    (*(nextchar + 2) == '/'))) {
138*0Sstevel@tonic-gate 				/* EMPTY */;
139*0Sstevel@tonic-gate 			} else {
140*0Sstevel@tonic-gate 
141*0Sstevel@tonic-gate 				/*
142*0Sstevel@tonic-gate 				 * 	prepare to eliminate either
143*0Sstevel@tonic-gate 				 *	"dir_name/../" or "dir_name/.."
144*0Sstevel@tonic-gate 				 */
145*0Sstevel@tonic-gate 
146*0Sstevel@tonic-gate 				if (*(lastchar + 3) == '/')
147*0Sstevel@tonic-gate 					lastchar += 4;
148*0Sstevel@tonic-gate 				else
149*0Sstevel@tonic-gate 					lastchar += 3;
150*0Sstevel@tonic-gate 
151*0Sstevel@tonic-gate 				/*
152*0Sstevel@tonic-gate 				 *	copy everything after the "/.." to
153*0Sstevel@tonic-gate 				 *	before the preceding directory name
154*0Sstevel@tonic-gate 				 */
155*0Sstevel@tonic-gate 
156*0Sstevel@tonic-gate 				sofar = nextchar - 1;
157*0Sstevel@tonic-gate 				while ((*nextchar++ = *lastchar++) != '\0');
158*0Sstevel@tonic-gate 
159*0Sstevel@tonic-gate 				lastchar = sofar;
160*0Sstevel@tonic-gate 
161*0Sstevel@tonic-gate 				/*
162*0Sstevel@tonic-gate 				 *	if the character before what was taken
163*0Sstevel@tonic-gate 				 *	out is '/', set up to check if the
164*0Sstevel@tonic-gate 				 *	slash is part of "/.."
165*0Sstevel@tonic-gate 				 */
166*0Sstevel@tonic-gate 
167*0Sstevel@tonic-gate 				if ((sofar + 1 != pathname) && (*sofar == '/'))
168*0Sstevel@tonic-gate 					--lastchar;
169*0Sstevel@tonic-gate 			}
170*0Sstevel@tonic-gate 		}
171*0Sstevel@tonic-gate 
172*0Sstevel@tonic-gate 	/*
173*0Sstevel@tonic-gate 	 *	if the string is more than a character long and ends
174*0Sstevel@tonic-gate 	 *	in '/', eliminate the '/'.
175*0Sstevel@tonic-gate 	 */
176*0Sstevel@tonic-gate 
177*0Sstevel@tonic-gate 	pnlen = strlen(pathname);
178*0Sstevel@tonic-gate 	pnend = strchr(pathname, '\0') - 1;
179*0Sstevel@tonic-gate 
180*0Sstevel@tonic-gate 	if ((pnlen > 1) && (*pnend == '/')) {
181*0Sstevel@tonic-gate 		*pnend-- = '\0';
182*0Sstevel@tonic-gate 		pnlen--;
183*0Sstevel@tonic-gate 	}
184*0Sstevel@tonic-gate 
185*0Sstevel@tonic-gate 	/*
186*0Sstevel@tonic-gate 	 *	if the string has more than two characters and ends in
187*0Sstevel@tonic-gate 	 *	"/.", remove the "/.".
188*0Sstevel@tonic-gate 	 */
189*0Sstevel@tonic-gate 
190*0Sstevel@tonic-gate 	if ((pnlen > 2) && (*(pnend - 1) == '/') && (*pnend == '.'))
191*0Sstevel@tonic-gate 		*--pnend = '\0';
192*0Sstevel@tonic-gate 
193*0Sstevel@tonic-gate 	/*
194*0Sstevel@tonic-gate 	 *	if all characters were deleted, return ".";
195*0Sstevel@tonic-gate 	 *	otherwise return pathname
196*0Sstevel@tonic-gate 	 */
197*0Sstevel@tonic-gate 
198*0Sstevel@tonic-gate 	if (*pathname == '\0')
199*0Sstevel@tonic-gate 		(void) strcpy(pathname, ".");
200*0Sstevel@tonic-gate 
201*0Sstevel@tonic-gate 	return (pathname);
202*0Sstevel@tonic-gate }
203