environment.c revision 178825 
1118856Sphk/*
2118856Sphk * Copyright (c) 2000, 2005 Kungliga Tekniska H�gskolan
3118856Sphk * (Royal Institute of Technology, Stockholm, Sweden).
4125500Sru * All rights reserved.
5118856Sphk *
6118856Sphk * Redistribution and use in source and binary forms, with or without
7118856Sphk * modification, are permitted provided that the following conditions
8118856Sphk * are met:
9118856Sphk *
10118856Sphk * 1. Redistributions of source code must retain the above copyright
11118856Sphk *    notice, this list of conditions and the following disclaimer.
12118856Sphk *
13118856Sphk * 2. Redistributions in binary form must reproduce the above copyright
14121795Sphk *    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#ifdef HAVE_CONFIG_H
36#include <config.h>
37RCSID("$Id: environment.c 20866 2007-06-03 21:00:29Z lha $");
38#endif
39
40#include <stdio.h>
41#include <string.h>
42#include <ctype.h>
43#include "roken.h"
44
45/* find assignment in env list; len is length of variable including
46 * equal
47 */
48
49static int
50find_var(char **env, char *assignment, size_t len)
51{
52    int i;
53    for(i = 0; env != NULL && env[i] != NULL; i++)
54	if(strncmp(env[i], assignment, len) == 0)
55	    return i;
56    return -1;
57}
58
59/*
60 * return count of environment assignments from open file F in
61 * assigned and list of malloced strings in env, return 0 or errno
62 * number
63 */
64
65static int
66rk_read_env_file(FILE *F, char ***env, int *assigned)
67{
68    int idx = 0;
69    int i;
70    char **l;
71    char buf[BUFSIZ], *p, *r;
72    char **tmp;
73    int ret = 0;
74
75    *assigned = 0;
76
77    for(idx = 0; *env != NULL && (*env)[idx] != NULL; idx++);
78    l = *env;
79
80    /* This is somewhat more relaxed on what it accepts then
81     * Wietses sysv_environ from K4 was...
82     */
83    while (fgets(buf, BUFSIZ, F) != NULL) {
84	buf[strcspn(buf, "#\n")] = '\0';
85
86	for(p = buf; isspace((unsigned char)*p); p++);
87	if (*p == '\0')
88	    continue;
89
90	/* Here one should check that it's a 'valid' env string... */
91	r = strchr(p, '=');
92	if (r == NULL)
93	    continue;
94
95	if((i = find_var(l, p, r - p + 1)) >= 0) {
96	    char *val = strdup(p);
97	    if(val == NULL) {
98		ret = ENOMEM;
99		break;
100	    }
101	    free(l[i]);
102	    l[i] = val;
103	    (*assigned)++;
104	    continue;
105	}
106
107	tmp = realloc(l, (idx+2) * sizeof (char *));
108	if(tmp == NULL) {
109	    ret = ENOMEM;
110	    break;
111	}
112
113	l = tmp;
114	l[idx] = strdup(p);
115	if(l[idx] == NULL) {
116	    ret = ENOMEM;
117	    break;
118	}
119	l[++idx] = NULL;
120	(*assigned)++;
121    }
122    if(ferror(F))
123	ret = errno;
124    *env = l;
125    return ret;
126}
127
128/*
129 * return count of environment assignments from file and
130 * list of malloced strings in `env'
131 */
132
133int ROKEN_LIB_FUNCTION
134read_environment(const char *file, char ***env)
135{
136    int assigned;
137    FILE *F;
138
139    if ((F = fopen(file, "r")) == NULL)
140	return 0;
141
142    rk_read_env_file(F, env, &assigned);
143    fclose(F);
144    return assigned;
145}
146
147void ROKEN_LIB_FUNCTION
148free_environment(char **env)
149{
150    int i;
151    if (env == NULL)
152	return;
153    for (i = 0; env[i]; i++)
154	free(env[i]);
155    free(env);
156}
157