1 files changed, 183 insertions, 0 deletions
diff --git a/gdbsupport/environ.c b/gdbsupport/environ.c
new file mode 100644
index 0000000..55d0a74
--- /dev/null
+++ b/gdbsupport/environ.c
@@ -0,0 +1,183 @@
+/* environ.c -- library for manipulating environments for GNU.
+
+   Copyright (C) 1986-2020 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include "common-defs.h"
+#include "environ.h"
+#include <algorithm>
+#include <utility>
+
+/* See gdbsupport/environ.h.  */
+
+gdb_environ &
+gdb_environ::operator= (gdb_environ &&e)
+{
+  /* Are we self-moving?  */
+  if (&e == this)
+    return *this;
+
+  m_environ_vector = std::move (e.m_environ_vector);
+  m_user_set_env = std::move (e.m_user_set_env);
+  m_user_unset_env = std::move (e.m_user_unset_env);
+  e.m_environ_vector.clear ();
+  e.m_environ_vector.push_back (NULL);
+  e.m_user_set_env.clear ();
+  e.m_user_unset_env.clear ();
+  return *this;
+}
+
+/* See gdbsupport/environ.h.  */
+
+gdb_environ gdb_environ::from_host_environ ()
+{
+  extern char **environ;
+  gdb_environ e;
+
+  if (environ == NULL)
+    return e;
+
+  for (int i = 0; environ[i] != NULL; ++i)
+    {
+      /* Make sure we add the element before the last (NULL).  */
+      e.m_environ_vector.insert (e.m_environ_vector.end () - 1,
+				 xstrdup (environ[i]));
+    }
+
+  return e;
+}
+
+/* See gdbsupport/environ.h.  */
+
+void
+gdb_environ::clear ()
+{
+  for (char *v : m_environ_vector)
+    xfree (v);
+  m_environ_vector.clear ();
+  /* Always add the NULL element.  */
+  m_environ_vector.push_back (NULL);
+  m_user_set_env.clear ();
+  m_user_unset_env.clear ();
+}
+
+/* Helper function to check if STRING contains an environment variable
+   assignment of VAR, i.e., if STRING starts with 'VAR='.  Return true
+   if it contains, false otherwise.  */
+
+static bool
+match_var_in_string (const char *string, const char *var, size_t var_len)
+{
+  if (strncmp (string, var, var_len) == 0 && string[var_len] == '=')
+    return true;
+
+  return false;
+}
+
+/* See gdbsupport/environ.h.  */
+
+const char *
+gdb_environ::get (const char *var) const
+{
+  size_t len = strlen (var);
+
+  for (char *el : m_environ_vector)
+    if (el != NULL && match_var_in_string (el, var, len))
+      return &el[len + 1];
+
+  return NULL;
+}
+
+/* See gdbsupport/environ.h.  */
+
+void
+gdb_environ::set (const char *var, const char *value)
+{
+  char *fullvar = concat (var, "=", value, NULL);
+
+  /* We have to unset the variable in the vector if it exists.  */
+  unset (var, false);
+
+  /* Insert the element before the last one, which is always NULL.  */
+  m_environ_vector.insert (m_environ_vector.end () - 1, fullvar);
+
+  /* Mark this environment variable as having been set by the user.
+     This will be useful when we deal with setting environment
+     variables on the remote target.  */
+  m_user_set_env.insert (std::string (fullvar));
+
+  /* If this environment variable is marked as unset by the user, then
+     remove it from the list, because now the user wants to set
+     it.  */
+  m_user_unset_env.erase (std::string (var));
+}
+
+/* See gdbsupport/environ.h.  */
+
+void
+gdb_environ::unset (const char *var, bool update_unset_list)
+{
+  size_t len = strlen (var);
+  std::vector<char *>::iterator it_env;
+
+  /* We iterate until '.end () - 1' because the last element is
+     always NULL.  */
+  for (it_env = m_environ_vector.begin ();
+       it_env != m_environ_vector.end () - 1;
+       ++it_env)
+    if (match_var_in_string (*it_env, var, len))
+      break;
+
+  if (it_env != m_environ_vector.end () - 1)
+    {
+      m_user_set_env.erase (std::string (*it_env));
+      xfree (*it_env);
+
+      m_environ_vector.erase (it_env);
+    }
+
+  if (update_unset_list)
+    m_user_unset_env.insert (std::string (var));
+}
+
+/* See gdbsupport/environ.h.  */
+
+void
+gdb_environ::unset (const char *var)
+{
+  unset (var, true);
+}
+
+/* See gdbsupport/environ.h.  */
+
+char **
+gdb_environ::envp () const
+{
+  return const_cast<char **> (&m_environ_vector[0]);
+}
+
+/* See gdbsupport/environ.h.  */
+
+const std::set<std::string> &
+gdb_environ::user_set_env () const
+{
+  return m_user_set_env;
+}
+
+const std::set<std::string> &
+gdb_environ::user_unset_env () const
+{
+  return m_user_unset_env;
+}