| 1 | /* environ.c -- library for manipulating environments for GNU. |
| 2 | |
| 3 | Copyright (C) 1986-2020 Free Software Foundation, Inc. |
| 4 | |
| 5 | This program is free software; you can redistribute it and/or modify |
| 6 | it under the terms of the GNU General Public License as published by |
| 7 | the Free Software Foundation; either version 3 of the License, or |
| 8 | (at your option) any later version. |
| 9 | |
| 10 | This program is distributed in the hope that it will be useful, |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | GNU General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU General Public License |
| 16 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 17 | |
| 18 | #include "common-defs.h" |
| 19 | #include "environ.h" |
| 20 | #include <algorithm> |
| 21 | #include <utility> |
| 22 | |
| 23 | /* See gdbsupport/environ.h. */ |
| 24 | |
| 25 | gdb_environ & |
| 26 | gdb_environ::operator= (gdb_environ &&e) |
| 27 | { |
| 28 | /* Are we self-moving? */ |
| 29 | if (&e == this) |
| 30 | return *this; |
| 31 | |
| 32 | m_environ_vector = std::move (e.m_environ_vector); |
| 33 | m_user_set_env = std::move (e.m_user_set_env); |
| 34 | m_user_unset_env = std::move (e.m_user_unset_env); |
| 35 | e.m_environ_vector.clear (); |
| 36 | e.m_environ_vector.push_back (NULL); |
| 37 | e.m_user_set_env.clear (); |
| 38 | e.m_user_unset_env.clear (); |
| 39 | return *this; |
| 40 | } |
| 41 | |
| 42 | /* See gdbsupport/environ.h. */ |
| 43 | |
| 44 | gdb_environ gdb_environ::from_host_environ () |
| 45 | { |
| 46 | extern char **environ; |
| 47 | gdb_environ e; |
| 48 | |
| 49 | if (environ == NULL) |
| 50 | return e; |
| 51 | |
| 52 | for (int i = 0; environ[i] != NULL; ++i) |
| 53 | { |
| 54 | /* Make sure we add the element before the last (NULL). */ |
| 55 | e.m_environ_vector.insert (e.m_environ_vector.end () - 1, |
| 56 | xstrdup (environ[i])); |
| 57 | } |
| 58 | |
| 59 | return e; |
| 60 | } |
| 61 | |
| 62 | /* See gdbsupport/environ.h. */ |
| 63 | |
| 64 | void |
| 65 | gdb_environ::clear () |
| 66 | { |
| 67 | for (char *v : m_environ_vector) |
| 68 | xfree (v); |
| 69 | m_environ_vector.clear (); |
| 70 | /* Always add the NULL element. */ |
| 71 | m_environ_vector.push_back (NULL); |
| 72 | m_user_set_env.clear (); |
| 73 | m_user_unset_env.clear (); |
| 74 | } |
| 75 | |
| 76 | /* Helper function to check if STRING contains an environment variable |
| 77 | assignment of VAR, i.e., if STRING starts with 'VAR='. Return true |
| 78 | if it contains, false otherwise. */ |
| 79 | |
| 80 | static bool |
| 81 | match_var_in_string (const char *string, const char *var, size_t var_len) |
| 82 | { |
| 83 | if (strncmp (string, var, var_len) == 0 && string[var_len] == '=') |
| 84 | return true; |
| 85 | |
| 86 | return false; |
| 87 | } |
| 88 | |
| 89 | /* See gdbsupport/environ.h. */ |
| 90 | |
| 91 | const char * |
| 92 | gdb_environ::get (const char *var) const |
| 93 | { |
| 94 | size_t len = strlen (var); |
| 95 | |
| 96 | for (char *el : m_environ_vector) |
| 97 | if (el != NULL && match_var_in_string (el, var, len)) |
| 98 | return &el[len + 1]; |
| 99 | |
| 100 | return NULL; |
| 101 | } |
| 102 | |
| 103 | /* See gdbsupport/environ.h. */ |
| 104 | |
| 105 | void |
| 106 | gdb_environ::set (const char *var, const char *value) |
| 107 | { |
| 108 | char *fullvar = concat (var, "=", value, NULL); |
| 109 | |
| 110 | /* We have to unset the variable in the vector if it exists. */ |
| 111 | unset (var, false); |
| 112 | |
| 113 | /* Insert the element before the last one, which is always NULL. */ |
| 114 | m_environ_vector.insert (m_environ_vector.end () - 1, fullvar); |
| 115 | |
| 116 | /* Mark this environment variable as having been set by the user. |
| 117 | This will be useful when we deal with setting environment |
| 118 | variables on the remote target. */ |
| 119 | m_user_set_env.insert (std::string (fullvar)); |
| 120 | |
| 121 | /* If this environment variable is marked as unset by the user, then |
| 122 | remove it from the list, because now the user wants to set |
| 123 | it. */ |
| 124 | m_user_unset_env.erase (std::string (var)); |
| 125 | } |
| 126 | |
| 127 | /* See gdbsupport/environ.h. */ |
| 128 | |
| 129 | void |
| 130 | gdb_environ::unset (const char *var, bool update_unset_list) |
| 131 | { |
| 132 | size_t len = strlen (var); |
| 133 | std::vector<char *>::iterator it_env; |
| 134 | |
| 135 | /* We iterate until '.end () - 1' because the last element is |
| 136 | always NULL. */ |
| 137 | for (it_env = m_environ_vector.begin (); |
| 138 | it_env != m_environ_vector.end () - 1; |
| 139 | ++it_env) |
| 140 | if (match_var_in_string (*it_env, var, len)) |
| 141 | break; |
| 142 | |
| 143 | if (it_env != m_environ_vector.end () - 1) |
| 144 | { |
| 145 | m_user_set_env.erase (std::string (*it_env)); |
| 146 | xfree (*it_env); |
| 147 | |
| 148 | m_environ_vector.erase (it_env); |
| 149 | } |
| 150 | |
| 151 | if (update_unset_list) |
| 152 | m_user_unset_env.insert (std::string (var)); |
| 153 | } |
| 154 | |
| 155 | /* See gdbsupport/environ.h. */ |
| 156 | |
| 157 | void |
| 158 | gdb_environ::unset (const char *var) |
| 159 | { |
| 160 | unset (var, true); |
| 161 | } |
| 162 | |
| 163 | /* See gdbsupport/environ.h. */ |
| 164 | |
| 165 | char ** |
| 166 | gdb_environ::envp () const |
| 167 | { |
| 168 | return const_cast<char **> (&m_environ_vector[0]); |
| 169 | } |
| 170 | |
| 171 | /* See gdbsupport/environ.h. */ |
| 172 | |
| 173 | const std::set<std::string> & |
| 174 | gdb_environ::user_set_env () const |
| 175 | { |
| 176 | return m_user_set_env; |
| 177 | } |
| 178 | |
| 179 | const std::set<std::string> & |
| 180 | gdb_environ::user_unset_env () const |
| 181 | { |
| 182 | return m_user_unset_env; |
| 183 | } |