| 1 | /* environ.c -- library for manipulating environments for GNU. |
| 2 | Copyright (C) 1986, 1989 Free Software Foundation, Inc. |
| 3 | |
| 4 | This program is free software; you can redistribute it and/or modify |
| 5 | it under the terms of the GNU General Public License as published by |
| 6 | the Free Software Foundation; either version 2 of the License, or |
| 7 | (at your option) any later version. |
| 8 | |
| 9 | This program is distributed in the hope that it will be useful, |
| 10 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 | GNU General Public License for more details. |
| 13 | |
| 14 | You should have received a copy of the GNU General Public License |
| 15 | along with this program; if not, write to the Free Software |
| 16 | Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ |
| 17 | |
| 18 | #define min(a, b) ((a) < (b) ? (a) : (b)) |
| 19 | #define max(a, b) ((a) > (b) ? (a) : (b)) |
| 20 | |
| 21 | #include "defs.h" |
| 22 | #include "environ.h" |
| 23 | #include <string.h> |
| 24 | #include "defs.h" /* For strsave(). */ |
| 25 | |
| 26 | \f |
| 27 | /* Return a new environment object. */ |
| 28 | |
| 29 | struct environ * |
| 30 | make_environ () |
| 31 | { |
| 32 | register struct environ *e; |
| 33 | |
| 34 | e = (struct environ *) xmalloc (sizeof (struct environ)); |
| 35 | |
| 36 | e->allocated = 10; |
| 37 | e->vector = (char **) xmalloc ((e->allocated + 1) * sizeof (char *)); |
| 38 | e->vector[0] = 0; |
| 39 | return e; |
| 40 | } |
| 41 | |
| 42 | /* Free an environment and all the strings in it. */ |
| 43 | |
| 44 | void |
| 45 | free_environ (e) |
| 46 | register struct environ *e; |
| 47 | { |
| 48 | register char **vector = e->vector; |
| 49 | |
| 50 | while (*vector) |
| 51 | free (*vector++); |
| 52 | |
| 53 | free (e); |
| 54 | } |
| 55 | |
| 56 | /* Copy the environment given to this process into E. |
| 57 | Also copies all the strings in it, so we can be sure |
| 58 | that all strings in these environments are safe to free. */ |
| 59 | |
| 60 | void |
| 61 | init_environ (e) |
| 62 | register struct environ *e; |
| 63 | { |
| 64 | extern char **environ; |
| 65 | register int i; |
| 66 | |
| 67 | for (i = 0; environ[i]; i++) /*EMPTY*/; |
| 68 | |
| 69 | if (e->allocated < i) |
| 70 | { |
| 71 | e->allocated = max (i, e->allocated + 10); |
| 72 | e->vector = (char **) xrealloc ((char *)e->vector, |
| 73 | (e->allocated + 1) * sizeof (char *)); |
| 74 | } |
| 75 | |
| 76 | (void) memcpy (e->vector, environ, (i + 1) * sizeof (char *)); |
| 77 | |
| 78 | while (--i >= 0) |
| 79 | { |
| 80 | register int len = strlen (e->vector[i]); |
| 81 | register char *new = (char *) xmalloc (len + 1); |
| 82 | (void) memcpy (new, e->vector[i], len + 1); |
| 83 | e->vector[i] = new; |
| 84 | } |
| 85 | } |
| 86 | |
| 87 | /* Return the vector of environment E. |
| 88 | This is used to get something to pass to execve. */ |
| 89 | |
| 90 | char ** |
| 91 | environ_vector (e) |
| 92 | struct environ *e; |
| 93 | { |
| 94 | return e->vector; |
| 95 | } |
| 96 | \f |
| 97 | /* Return the value in environment E of variable VAR. */ |
| 98 | |
| 99 | char * |
| 100 | get_in_environ (e, var) |
| 101 | const struct environ *e; |
| 102 | const char *var; |
| 103 | { |
| 104 | register int len = strlen (var); |
| 105 | register char **vector = e->vector; |
| 106 | register char *s; |
| 107 | |
| 108 | for (; (s = *vector) != NULL; vector++) |
| 109 | if (!strncmp (s, var, len) |
| 110 | && s[len] == '=') |
| 111 | return &s[len + 1]; |
| 112 | |
| 113 | return 0; |
| 114 | } |
| 115 | |
| 116 | /* Store the value in E of VAR as VALUE. */ |
| 117 | |
| 118 | void |
| 119 | set_in_environ (e, var, value) |
| 120 | struct environ *e; |
| 121 | const char *var; |
| 122 | const char *value; |
| 123 | { |
| 124 | register int i; |
| 125 | register int len = strlen (var); |
| 126 | register char **vector = e->vector; |
| 127 | register char *s; |
| 128 | |
| 129 | for (i = 0; (s = vector[i]) != NULL; i++) |
| 130 | if (!strncmp (s, var, len) |
| 131 | && s[len] == '=') |
| 132 | break; |
| 133 | |
| 134 | if (s == 0) |
| 135 | { |
| 136 | if (i == e->allocated) |
| 137 | { |
| 138 | e->allocated += 10; |
| 139 | vector = (char **) xrealloc ((char *)vector, |
| 140 | (e->allocated + 1) * sizeof (char *)); |
| 141 | e->vector = vector; |
| 142 | } |
| 143 | vector[i + 1] = 0; |
| 144 | } |
| 145 | else |
| 146 | free (s); |
| 147 | |
| 148 | s = (char *) xmalloc (len + strlen (value) + 2); |
| 149 | strcpy (s, var); |
| 150 | strcat (s, "="); |
| 151 | strcat (s, value); |
| 152 | vector[i] = s; |
| 153 | |
| 154 | /* Certain variables get exported back to the parent (e.g. our) |
| 155 | environment, too. */ |
| 156 | if (!strcmp(var, "PATH") /* Object file location */ |
| 157 | || !strcmp (var, "G960BASE") /* Intel 960 downloads */ |
| 158 | || !strcmp (var, "G960BIN") /* Intel 960 downloads */ |
| 159 | || !strcmp (var, "GNUTARGET") /* BFD object file type */ |
| 160 | ) { |
| 161 | putenv (strsave (s)); |
| 162 | } |
| 163 | return; |
| 164 | } |
| 165 | |
| 166 | /* Remove the setting for variable VAR from environment E. */ |
| 167 | |
| 168 | void |
| 169 | unset_in_environ (e, var) |
| 170 | struct environ *e; |
| 171 | char *var; |
| 172 | { |
| 173 | register int len = strlen (var); |
| 174 | register char **vector = e->vector; |
| 175 | register char *s; |
| 176 | |
| 177 | for (; (s = *vector) != NULL; vector++) |
| 178 | if (!strncmp (s, var, len) |
| 179 | && s[len] == '=') |
| 180 | { |
| 181 | free (s); |
| 182 | (void) memcpy (vector, vector + 1, |
| 183 | (e->allocated - (vector - e->vector)) * sizeof (char *)); |
| 184 | e->vector[e->allocated - 1] = 0; |
| 185 | return; |
| 186 | } |
| 187 | } |