xref: /freebsd/crypto/heimdal/lib/roken/environment.c (revision cc68614da8232d8baaca0ae0d0dd8f890f06623e)
1 /*
2  * Copyright (c) 2000, 2005 Kungliga Tekniska Högskolan
3  * (Royal Institute of Technology, Stockholm, Sweden).
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  *
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  *
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * 3. Neither the name of the Institute nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 
35 #include <config.h>
36 
37 #include <stdio.h>
38 #include <string.h>
39 #include <ctype.h>
40 #include "roken.h"
41 
42 /* find assignment in env list; len is length of variable including
43  * equal
44  */
45 
46 static int
47 find_var(char **env, char *assignment, size_t len)
48 {
49     int i;
50     for(i = 0; env != NULL && env[i] != NULL; i++)
51 	if(strncmp(env[i], assignment, len) == 0)
52 	    return i;
53     return -1;
54 }
55 
56 /*
57  * return count of environment assignments from open file F in
58  * assigned and list of malloced strings in env, return 0 or errno
59  * number
60  */
61 
62 static int
63 read_env_file(FILE *F, char ***env, int *assigned)
64 {
65     int idx = 0;
66     int i;
67     char **l;
68     char buf[BUFSIZ], *p, *r;
69     char **tmp;
70     int ret = 0;
71 
72     *assigned = 0;
73 
74     for(idx = 0; *env != NULL && (*env)[idx] != NULL; idx++);
75     l = *env;
76 
77     /* This is somewhat more relaxed on what it accepts then
78      * Wietses sysv_environ from K4 was...
79      */
80     while (fgets(buf, BUFSIZ, F) != NULL) {
81 	buf[strcspn(buf, "#\n")] = '\0';
82 
83 	for(p = buf; isspace((unsigned char)*p); p++);
84 	if (*p == '\0')
85 	    continue;
86 
87 	/* Here one should check that it's a 'valid' env string... */
88 	r = strchr(p, '=');
89 	if (r == NULL)
90 	    continue;
91 
92 	if((i = find_var(l, p, r - p + 1)) >= 0) {
93 	    char *val = strdup(p);
94 	    if(val == NULL) {
95 		ret = ENOMEM;
96 		break;
97 	    }
98 	    free(l[i]);
99 	    l[i] = val;
100 	    (*assigned)++;
101 	    continue;
102 	}
103 
104 	tmp = realloc(l, (idx+2) * sizeof (char *));
105 	if(tmp == NULL) {
106 	    ret = ENOMEM;
107 	    break;
108 	}
109 
110 	l = tmp;
111 	l[idx] = strdup(p);
112 	if(l[idx] == NULL) {
113 	    ret = ENOMEM;
114 	    break;
115 	}
116 	l[++idx] = NULL;
117 	(*assigned)++;
118     }
119     if(ferror(F))
120 	ret = errno;
121     *env = l;
122     return ret;
123 }
124 
125 /*
126  * return count of environment assignments from file and
127  * list of malloced strings in `env'
128  */
129 
130 ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
131 read_environment(const char *file, char ***env)
132 {
133     int assigned;
134     FILE *F;
135 
136     if ((F = fopen(file, "r")) == NULL)
137 	return 0;
138 
139     read_env_file(F, env, &assigned);
140     fclose(F);
141     return assigned;
142 }
143 
144 ROKEN_LIB_FUNCTION void ROKEN_LIB_CALL
145 free_environment(char **env)
146 {
147     int i;
148     if (env == NULL)
149 	return;
150     for (i = 0; env[i]; i++)
151 	free(env[i]);
152     free(env);
153 }
154