Move gdbsupport to the top level

This patch moves the gdbsupport directory to the top level.  This is
the next step in the ongoing project to move gdbserver to the top
level.

The bulk of this patch was created by "git mv gdb/gdbsupport gdbsupport".

This patch then adds a build system to gdbsupport and wires it into
the top level.  Then it changes gdb to use the top-level build.

gdbserver, on the other hand, is not yet changed.  It still does its
own build of gdbsupport.

ChangeLog
2020-01-14  Tom Tromey  <tom@tromey.com>

	* src-release.sh (GDB_SUPPORT_DIRS): Add gdbsupport.
	* MAINTAINERS: Add gdbsupport.
	* configure: Rebuild.
	* configure.ac (configdirs): Add gdbsupport.
	* gdbsupport: New directory, move from gdb/gdbsupport.
	* Makefile.def (host_modules, dependencies): Add gnulib.
	* Makefile.in: Rebuild.

gdb/ChangeLog
2020-01-14  Tom Tromey  <tom@tromey.com>

	* nat/x86-linux-dregs.c: Include configh.h.
	* nat/linux-ptrace.c: Include configh.h.
	* nat/linux-btrace.c: Include configh.h.
	* defs.h: Include config.h, bfd.h.
	* configure.ac: Don't source common.host.
	(CONFIG_OBS, CONFIG_SRCS): Remove gdbsupport files.
	* configure: Rebuild.
	* acinclude.m4: Update path.
	* Makefile.in (SUPPORT, LIBSUPPORT, INCSUPPORT): New variables.
	(CONFIG_SRC_SUBDIR): Remove gdbsupport.
	(INTERNAL_CFLAGS_BASE): Add INCSUPPORT.
	(CLIBS): Add LIBSUPPORT.
	(CDEPS): Likewise.
	(COMMON_SFILES): Remove gdbsupport files.
	(HFILES_NO_SRCDIR): Likewise.
	(stamp-version): Update path to create-version.sh.
	(ALLDEPFILES): Remove gdbsupport files.

gdb/gdbserver/ChangeLog
2020-01-14  Tom Tromey  <tom@tromey.com>

	* server.h: Include config.h.
	* gdbreplay.c: Include config.h.
	* configure: Rebuild.
	* configure.ac: Don't source common.host.
	* acinclude.m4: Update path.
	* Makefile.in (INCSUPPORT): New variable.
	(INCLUDE_CFLAGS): Add INCSUPPORT.
	(SFILES): Update paths.
	(version-generated.c): Update path to create-version.sh.
	(gdbsupport/%-ipa.o, gdbsupport/%.o): Update paths.

gdbsupport/ChangeLog
2020-01-14  Tom Tromey  <tom@tromey.com>

	* common-defs.h: Add GDBSERVER case.  Update includes.
	* acinclude.m4, aclocal.m4, config.in, configure, configure.ac,
	Makefile.am, Makefile.in, README: New files.
	* Moved from ../gdb/gdbsupport/

Change-Id: I07632e7798635c1bab389bf885971e584fb4bb78

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;
+}