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) 1984, 1986, 1987, 1988, 1989 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 /*LINTLIBRARY*/
33*0Sstevel@tonic-gate 
34*0Sstevel@tonic-gate /*
35*0Sstevel@tonic-gate  *  NAME
36*0Sstevel@tonic-gate  *	xsetenv, xgetenv, Xgetenv - manage an alternate environment space
37*0Sstevel@tonic-gate  *
38*0Sstevel@tonic-gate  *  SYNOPSIS
39*0Sstevel@tonic-gate  *	int ret = xsetenv(file)
40*0Sstevel@tonic-gate  *	char *x = xgetenv("FOO");
41*0Sstevel@tonic-gate  *	char *x = Xgetenv("FOO");
42*0Sstevel@tonic-gate  *
43*0Sstevel@tonic-gate  *  DESCRIPTION
44*0Sstevel@tonic-gate  *	xsetenv() reads the given file into an internal buffer
45*0Sstevel@tonic-gate  *	and sets up an alternate environment.
46*0Sstevel@tonic-gate  *
47*0Sstevel@tonic-gate  *	Return values:	1 - OKAY
48*0Sstevel@tonic-gate  *			0 - troubles reading the file
49*0Sstevel@tonic-gate  *			-1 - troubles opening the file
50*0Sstevel@tonic-gate  *
51*0Sstevel@tonic-gate  *	xgetenv() returns the environment value from the
52*0Sstevel@tonic-gate  *	alternate environment.
53*0Sstevel@tonic-gate  *
54*0Sstevel@tonic-gate  *	Return values:	(char *)0 - no value for that variable
55*0Sstevel@tonic-gate  *			pointer  - the value
56*0Sstevel@tonic-gate  *
57*0Sstevel@tonic-gate  *	Xgetenv() returns the environment value from the
58*0Sstevel@tonic-gate  *	alternate environment.
59*0Sstevel@tonic-gate  *
60*0Sstevel@tonic-gate  *	Return values:	"" - no value for that variable
61*0Sstevel@tonic-gate  *			pointer  - the value
62*0Sstevel@tonic-gate  *
63*0Sstevel@tonic-gate  *  LIMITATIONS
64*0Sstevel@tonic-gate  *	Assumes the environment is < 5120 bytes, as in the UNIX
65*0Sstevel@tonic-gate  *	System environment. Assumes < 512 lines in the file.
66*0Sstevel@tonic-gate  *	These values may be adjusted below.
67*0Sstevel@tonic-gate  */
68*0Sstevel@tonic-gate 
69*0Sstevel@tonic-gate #include "synonyms.h"
70*0Sstevel@tonic-gate #include <sys/types.h>
71*0Sstevel@tonic-gate #include "libmail.h"
72*0Sstevel@tonic-gate #include <stdio.h>
73*0Sstevel@tonic-gate #include <string.h>
74*0Sstevel@tonic-gate #include <fcntl.h>
75*0Sstevel@tonic-gate #include <ctype.h>
76*0Sstevel@tonic-gate 
77*0Sstevel@tonic-gate #include <stdlib.h>
78*0Sstevel@tonic-gate #include <unistd.h>
79*0Sstevel@tonic-gate 
80*0Sstevel@tonic-gate #define	MAXVARS  512
81*0Sstevel@tonic-gate #define	MAXENV  5120
82*0Sstevel@tonic-gate 
83*0Sstevel@tonic-gate static char **xenv = 0;
84*0Sstevel@tonic-gate static char *(xenvptrs[MAXVARS]);
85*0Sstevel@tonic-gate static char xbuf[MAXENV];
86*0Sstevel@tonic-gate 
87*0Sstevel@tonic-gate static void reduce(char *);
88*0Sstevel@tonic-gate 
89*0Sstevel@tonic-gate /*
90*0Sstevel@tonic-gate  *	set up an environment buffer
91*0Sstevel@tonic-gate  *	and the pointers into it
92*0Sstevel@tonic-gate  */
93*0Sstevel@tonic-gate int
94*0Sstevel@tonic-gate xsetenv(char *xfile)
95*0Sstevel@tonic-gate {
96*0Sstevel@tonic-gate 	int envctr, infd;
97*0Sstevel@tonic-gate 	ssize_t i, nread;
98*0Sstevel@tonic-gate 
99*0Sstevel@tonic-gate 	/* Open the file */
100*0Sstevel@tonic-gate 	infd = open(xfile, O_RDONLY);
101*0Sstevel@tonic-gate 	if (infd == -1) {
102*0Sstevel@tonic-gate 		return (-1);
103*0Sstevel@tonic-gate 	}
104*0Sstevel@tonic-gate 
105*0Sstevel@tonic-gate 	/* Read in the entire file. */
106*0Sstevel@tonic-gate 	nread = read(infd, xbuf, sizeof (xbuf));
107*0Sstevel@tonic-gate 	if (nread < 0) {
108*0Sstevel@tonic-gate 		(void) close(infd);
109*0Sstevel@tonic-gate 		return (0);
110*0Sstevel@tonic-gate 	}
111*0Sstevel@tonic-gate 
112*0Sstevel@tonic-gate 	/*
113*0Sstevel@tonic-gate 	 * Set up pointers into the buffer.
114*0Sstevel@tonic-gate 	 * Replace \n with \0.
115*0Sstevel@tonic-gate 	 * Collapse white space around the = sign and at the
116*0Sstevel@tonic-gate 	 * beginning and end of the line.
117*0Sstevel@tonic-gate 	 */
118*0Sstevel@tonic-gate 	xenv = xenvptrs;
119*0Sstevel@tonic-gate 	xenv[0] = &xbuf[0];
120*0Sstevel@tonic-gate 	for (i = 0, envctr = 0; i < nread; i++) {
121*0Sstevel@tonic-gate 		if (xbuf[i] == '\n') {
122*0Sstevel@tonic-gate 			xbuf[i] = '\0';
123*0Sstevel@tonic-gate 			reduce(xenv[envctr]);
124*0Sstevel@tonic-gate 			xenv[++envctr] = &xbuf[i+1];
125*0Sstevel@tonic-gate 			if (envctr == MAXVARS) {
126*0Sstevel@tonic-gate 				break;
127*0Sstevel@tonic-gate 			}
128*0Sstevel@tonic-gate 		}
129*0Sstevel@tonic-gate 	}
130*0Sstevel@tonic-gate 
131*0Sstevel@tonic-gate 	xenv[envctr] = 0;
132*0Sstevel@tonic-gate 	(void) close(infd);
133*0Sstevel@tonic-gate 	return (1);
134*0Sstevel@tonic-gate }
135*0Sstevel@tonic-gate 
136*0Sstevel@tonic-gate /*
137*0Sstevel@tonic-gate  *	Let getenv() do the dirty work
138*0Sstevel@tonic-gate  *	of looking up the variable. We
139*0Sstevel@tonic-gate  *	do this by temporarily resetting
140*0Sstevel@tonic-gate  *	environ to point to the local area.
141*0Sstevel@tonic-gate  */
142*0Sstevel@tonic-gate char *
143*0Sstevel@tonic-gate xgetenv(char *env)
144*0Sstevel@tonic-gate {
145*0Sstevel@tonic-gate 	extern char **environ;
146*0Sstevel@tonic-gate 	char *ret, **svenviron = environ;
147*0Sstevel@tonic-gate 
148*0Sstevel@tonic-gate 	environ = xenv;
149*0Sstevel@tonic-gate 	ret = getenv(env);
150*0Sstevel@tonic-gate 	environ = svenviron;
151*0Sstevel@tonic-gate 	return (ret);
152*0Sstevel@tonic-gate }
153*0Sstevel@tonic-gate 
154*0Sstevel@tonic-gate /*
155*0Sstevel@tonic-gate  *	Let xgetenv() do the dirty work
156*0Sstevel@tonic-gate  *	of looking up the variable.
157*0Sstevel@tonic-gate  */
158*0Sstevel@tonic-gate char *
159*0Sstevel@tonic-gate Xgetenv(char *env)
160*0Sstevel@tonic-gate {
161*0Sstevel@tonic-gate 	char *ret = xgetenv(env);
162*0Sstevel@tonic-gate 	return (ret ? ret : "");
163*0Sstevel@tonic-gate }
164*0Sstevel@tonic-gate 
165*0Sstevel@tonic-gate /*
166*0Sstevel@tonic-gate  * Remove the spaces within the environment variable.
167*0Sstevel@tonic-gate  * The variable can look like this:
168*0Sstevel@tonic-gate  *
169*0Sstevel@tonic-gate  * <sp1> variable <sp2> = <sp3> value <sp4> \0
170*0Sstevel@tonic-gate  *
171*0Sstevel@tonic-gate  * All spaces can be removed, except within
172*0Sstevel@tonic-gate  * the variable name and the value.
173*0Sstevel@tonic-gate  */
174*0Sstevel@tonic-gate 
175*0Sstevel@tonic-gate static void
176*0Sstevel@tonic-gate reduce(char *from)
177*0Sstevel@tonic-gate {
178*0Sstevel@tonic-gate 	char *to = from;
179*0Sstevel@tonic-gate 	char *svfrom = from;
180*0Sstevel@tonic-gate 
181*0Sstevel@tonic-gate 	/* <sp1> */
182*0Sstevel@tonic-gate 	while (*from &&isspace((int)*from))
183*0Sstevel@tonic-gate 		from++;
184*0Sstevel@tonic-gate 
185*0Sstevel@tonic-gate 	/* variable */
186*0Sstevel@tonic-gate 	while (*from && (*from != '=') && !isspace((int)*from))
187*0Sstevel@tonic-gate 		*to++ = *from++;
188*0Sstevel@tonic-gate 
189*0Sstevel@tonic-gate 	/* <sp2> */
190*0Sstevel@tonic-gate 	while (*from && isspace((int)*from))
191*0Sstevel@tonic-gate 		from++;
192*0Sstevel@tonic-gate 
193*0Sstevel@tonic-gate 	/* = */
194*0Sstevel@tonic-gate 	if (*from == '=')
195*0Sstevel@tonic-gate 		*to++ = *from++;
196*0Sstevel@tonic-gate 
197*0Sstevel@tonic-gate 	/* <sp3> */
198*0Sstevel@tonic-gate 	while (*from && isspace((int)*from))
199*0Sstevel@tonic-gate 		from++;
200*0Sstevel@tonic-gate 
201*0Sstevel@tonic-gate 	/* value */
202*0Sstevel@tonic-gate 	while (*from)
203*0Sstevel@tonic-gate 		*to++ = *from++;
204*0Sstevel@tonic-gate 
205*0Sstevel@tonic-gate 	/* <sp4> */
206*0Sstevel@tonic-gate 	while ((to > svfrom) && isspace((int)to[-1]))
207*0Sstevel@tonic-gate 		to--;
208*0Sstevel@tonic-gate 	*to = '\0';
209*0Sstevel@tonic-gate }
210