| 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 1, or (at your option) |
| 7 | 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 "environ.h" |
| 22 | #include <string.h> |
| 23 | |
| 24 | extern char *xmalloc (); |
| 25 | extern char *xrealloc (); |
| 26 | extern void free (); |
| 27 | \f |
| 28 | /* Return a new environment object. */ |
| 29 | |
| 30 | struct environ * |
| 31 | make_environ () |
| 32 | { |
| 33 | register struct environ *e; |
| 34 | |
| 35 | e = (struct environ *) xmalloc (sizeof (struct environ)); |
| 36 | |
| 37 | e->allocated = 10; |
| 38 | e->vector = (char **) xmalloc ((e->allocated + 1) * sizeof (char *)); |
| 39 | e->vector[0] = 0; |
| 40 | return e; |
| 41 | } |
| 42 | |
| 43 | /* Free an environment and all the strings in it. */ |
| 44 | |
| 45 | void |
| 46 | free_environ (e) |
| 47 | register struct environ *e; |
| 48 | { |
| 49 | register char **vector = e->vector; |
| 50 | |
| 51 | while (*vector) |
| 52 | free (*vector++); |
| 53 | |
| 54 | free (e); |
| 55 | } |
| 56 | |
| 57 | /* Copy the environment given to this process into E. |
| 58 | Also copies all the strings in it, so we can be sure |
| 59 | that all strings in these environments are safe to free. */ |
| 60 | |
| 61 | void |
| 62 | init_environ (e) |
| 63 | register struct environ *e; |
| 64 | { |
| 65 | extern char **environ; |
| 66 | register int i; |
| 67 | |
| 68 | for (i = 0; environ[i]; i++) /*EMPTY*/; |
| 69 | |
| 70 | if (e->allocated < i) |
| 71 | { |
| 72 | e->allocated = max (i, e->allocated + 10); |
| 73 | e->vector = (char **) xrealloc ((char *)e->vector, |
| 74 | (e->allocated + 1) * sizeof (char *)); |
| 75 | } |
| 76 | |
| 77 | bcopy (environ, e->vector, (i + 1) * sizeof (char *)); |
| 78 | |
| 79 | while (--i >= 0) |
| 80 | { |
| 81 | register int len = strlen (e->vector[i]); |
| 82 | register char *new = (char *) xmalloc (len + 1); |
| 83 | bcopy (e->vector[i], new, len + 1); |
| 84 | e->vector[i] = new; |
| 85 | } |
| 86 | } |
| 87 | |
| 88 | /* Return the vector of environment E. |
| 89 | This is used to get something to pass to execve. */ |
| 90 | |
| 91 | char ** |
| 92 | environ_vector (e) |
| 93 | struct environ *e; |
| 94 | { |
| 95 | return e->vector; |
| 96 | } |
| 97 | \f |
| 98 | /* Return the value in environment E of variable VAR. */ |
| 99 | |
| 100 | char * |
| 101 | get_in_environ (e, var) |
| 102 | struct environ *e; |
| 103 | char *var; |
| 104 | { |
| 105 | register int len = strlen (var); |
| 106 | register char **vector = e->vector; |
| 107 | register char *s; |
| 108 | |
| 109 | for (; s = *vector; vector++) |
| 110 | if (!strncmp (s, var, len) |
| 111 | && s[len] == '=') |
| 112 | return &s[len + 1]; |
| 113 | |
| 114 | return 0; |
| 115 | } |
| 116 | |
| 117 | /* Store the value in E of VAR as VALUE. */ |
| 118 | |
| 119 | void |
| 120 | set_in_environ (e, var, value) |
| 121 | struct environ *e; |
| 122 | char *var; |
| 123 | char *value; |
| 124 | { |
| 125 | register int i; |
| 126 | register int len = strlen (var); |
| 127 | register char **vector = e->vector; |
| 128 | register char *s; |
| 129 | |
| 130 | for (i = 0; s = vector[i]; i++) |
| 131 | if (!strncmp (s, var, len) |
| 132 | && s[len] == '=') |
| 133 | break; |
| 134 | |
| 135 | if (s == 0) |
| 136 | { |
| 137 | if (i == e->allocated) |
| 138 | { |
| 139 | e->allocated += 10; |
| 140 | vector = (char **) xrealloc ((char *)vector, |
| 141 | (e->allocated + 1) * sizeof (char *)); |
| 142 | e->vector = vector; |
| 143 | } |
| 144 | vector[i + 1] = 0; |
| 145 | } |
| 146 | else |
| 147 | free (s); |
| 148 | |
| 149 | s = (char *) xmalloc (len + strlen (value) + 2); |
| 150 | strcpy (s, var); |
| 151 | strcat (s, "="); |
| 152 | strcat (s, value); |
| 153 | vector[i] = s; |
| 154 | |
| 155 | /* Certain variables get exported back to the parent (e.g. our) |
| 156 | environment, too. */ |
| 157 | if (!strcmp(var, "PATH") /* Object file location */ |
| 158 | || !strcmp (var, "G960BASE") /* Intel 960 downloads */ |
| 159 | || !strcmp (var, "G960BIN") /* Intel 960 downloads */ |
| 160 | || !strcmp (var, "GNUTARGET") /* BFD object file type */ |
| 161 | ) { |
| 162 | putenv (strsave (s)); |
| 163 | } |
| 164 | return; |
| 165 | } |
| 166 | |
| 167 | /* Remove the setting for variable VAR from environment E. */ |
| 168 | |
| 169 | void |
| 170 | unset_in_environ (e, var) |
| 171 | struct environ *e; |
| 172 | char *var; |
| 173 | { |
| 174 | register int len = strlen (var); |
| 175 | register char **vector = e->vector; |
| 176 | register char *s; |
| 177 | |
| 178 | for (; s = *vector; vector++) |
| 179 | if (!strncmp (s, var, len) |
| 180 | && s[len] == '=') |
| 181 | { |
| 182 | free (s); |
| 183 | bcopy (vector + 1, vector, |
| 184 | (e->allocated - (vector - e->vector)) * sizeof (char *)); |
| 185 | e->vector[e->allocated - 1] = 0; |
| 186 | return; |
| 187 | } |
| 188 | } |