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, 304 insertions, 0 deletions

diff --git a/gdbsupport/common-exceptions.h b/gdbsupport/common-exceptions.h
new file mode 100644
index 0000000..76d916f
--- /dev/null
+++ b/gdbsupport/common-exceptions.h
@@ -0,0 +1,304 @@
+/* Exception (throw catch) mechanism, for GDB, the GNU debugger.
+
+   Copyright (C) 1986-2020 Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   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/>.  */
+
+#ifndef COMMON_COMMON_EXCEPTIONS_H
+#define COMMON_COMMON_EXCEPTIONS_H
+
+#include <setjmp.h>
+#include <new>
+#include <memory>
+#include <string>
+
+/* Reasons for calling throw_exceptions().  NOTE: all reason values
+   must be different from zero.  enum value 0 is reserved for internal
+   use as the return value from an initial setjmp().  */
+
+enum return_reason
+  {
+    /* User interrupt.  */
+    RETURN_QUIT = -2,
+    /* Any other error.  */
+    RETURN_ERROR
+  };
+
+#define RETURN_MASK(reason)	(1 << (int)(-reason))
+
+typedef enum
+{
+  RETURN_MASK_QUIT = RETURN_MASK (RETURN_QUIT),
+  RETURN_MASK_ERROR = RETURN_MASK (RETURN_ERROR),
+  RETURN_MASK_ALL = (RETURN_MASK_QUIT | RETURN_MASK_ERROR)
+} return_mask;
+
+/* Describe all exceptions.  */
+
+enum errors {
+  GDB_NO_ERROR,
+
+  /* Any generic error, the corresponding text is in
+     exception.message.  */
+  GENERIC_ERROR,
+
+  /* Something requested was not found.  */
+  NOT_FOUND_ERROR,
+
+  /* Thread library lacks support necessary for finding thread local
+     storage.  */
+  TLS_NO_LIBRARY_SUPPORT_ERROR,
+
+  /* Load module not found while attempting to find thread local storage.  */
+  TLS_LOAD_MODULE_NOT_FOUND_ERROR,
+
+  /* Thread local storage has not been allocated yet.  */
+  TLS_NOT_ALLOCATED_YET_ERROR,
+
+  /* Something else went wrong while attempting to find thread local
+     storage.  The ``struct gdb_exception'' message field provides
+     more detail.  */
+  TLS_GENERIC_ERROR,
+
+  /* Problem parsing an XML document.  */
+  XML_PARSE_ERROR,
+
+  /* Error accessing memory.  */
+  MEMORY_ERROR,
+
+  /* Value not available.  E.g., a register was not collected in a
+     traceframe.  */
+  NOT_AVAILABLE_ERROR,
+
+  /* Value was optimized out.  Note: if the value was a register, this
+     means the register was not saved in the frame.  */
+  OPTIMIZED_OUT_ERROR,
+
+  /* DW_OP_entry_value resolving failed.  */
+  NO_ENTRY_VALUE_ERROR,
+
+  /* Target throwing an error has been closed.  Current command should be
+     aborted as the inferior state is no longer valid.  */
+  TARGET_CLOSE_ERROR,
+
+  /* An undefined command was executed.  */
+  UNDEFINED_COMMAND_ERROR,
+
+  /* Requested feature, method, mechanism, etc. is not supported.  */
+  NOT_SUPPORTED_ERROR,
+
+  /* The number of candidates generated during line completion has
+     reached the user's specified limit.  This isn't an error, this exception
+     is used to halt searching for more completions, but for consistency
+     "_ERROR" is appended to the name.  */
+  MAX_COMPLETIONS_REACHED_ERROR,
+
+  /* Add more errors here.  */
+  NR_ERRORS
+};
+
+struct gdb_exception
+{
+  gdb_exception ()
+    : reason ((enum return_reason) 0),
+      error (GDB_NO_ERROR)
+  {
+  }
+
+  gdb_exception (enum return_reason r, enum errors e)
+    : reason (r),
+      error (e)
+  {
+  }
+
+  gdb_exception (enum return_reason r, enum errors e,
+		 const char *fmt, va_list ap)
+    ATTRIBUTE_PRINTF (4, 0)
+    : reason (r),
+      error (e),
+      message (std::make_shared<std::string> (string_vprintf (fmt, ap)))
+  {
+  }
+
+  /* The move constructor exists so that we can mark it "noexcept",
+     which is a good practice for any sort of exception object.  */
+  explicit gdb_exception (gdb_exception &&other) noexcept = default;
+
+  /* The copy constructor exists so that we can mark it "noexcept",
+     which is a good practice for any sort of exception object.  */
+  gdb_exception (const gdb_exception &other) noexcept
+    : reason (other.reason),
+      error (other.error),
+      message (other.message)
+  {
+  }
+
+  /* The assignment operator exists so that we can mark it "noexcept",
+     which is a good practice for any sort of exception object.  */
+  gdb_exception &operator= (const gdb_exception &other) noexcept
+  {
+    reason = other.reason;
+    error = other.error;
+    message = other.message;
+    return *this;
+  }
+
+  gdb_exception &operator= (gdb_exception &&other) noexcept = default;
+
+  /* Return the contents of the exception message, as a C string.  The
+     string remains owned by the exception object.  */
+  const char *what () const noexcept
+  {
+    return message->c_str ();
+  }
+
+  enum return_reason reason;
+  enum errors error;
+  std::shared_ptr<std::string> message;
+};
+
+/* Functions to drive the sjlj-based exceptions state machine.  Though
+   declared here by necessity, these functions should be considered
+   internal to the exceptions subsystem and not used other than via
+   the TRY/CATCH (or TRY_SJLJ/CATCH_SJLJ) macros defined below.  */
+
+extern jmp_buf *exceptions_state_mc_init (void);
+extern int exceptions_state_mc_action_iter (void);
+extern int exceptions_state_mc_action_iter_1 (void);
+extern int exceptions_state_mc_catch (struct gdb_exception *, int);
+
+/* Macro to wrap up standard try/catch behavior.
+
+   The double loop lets us correctly handle code "break"ing out of the
+   try catch block.  (It works as the "break" only exits the inner
+   "while" loop, the outer for loop detects this handling it
+   correctly.)  Of course "return" and "goto" are not so lucky.
+
+   For instance:
+
+   *INDENT-OFF*
+
+   TRY_SJLJ
+     {
+     }
+   CATCH_SJLJ (e, RETURN_MASK_ERROR)
+     {
+       switch (e.reason)
+         {
+           case RETURN_ERROR: ...
+         }
+     }
+   END_CATCH_SJLJ
+
+   The SJLJ variants are needed in some cases where gdb exceptions
+   need to cross third-party library code compiled without exceptions
+   support (e.g., readline).  */
+
+#define TRY_SJLJ \
+     { \
+       jmp_buf *buf = \
+	 exceptions_state_mc_init (); \
+       setjmp (*buf); \
+     } \
+     while (exceptions_state_mc_action_iter ()) \
+       while (exceptions_state_mc_action_iter_1 ())
+
+#define CATCH_SJLJ(EXCEPTION, MASK)				\
+  {							\
+    struct gdb_exception EXCEPTION;				\
+    if (exceptions_state_mc_catch (&(EXCEPTION), MASK))
+
+#define END_CATCH_SJLJ				\
+  }
+
+/* The exception types client code may catch.  They're just shims
+   around gdb_exception that add nothing but type info.  Which is used
+   is selected depending on the MASK argument passed to CATCH.  */
+
+struct gdb_exception_error : public gdb_exception
+{
+  gdb_exception_error (enum errors e, const char *fmt, va_list ap)
+    ATTRIBUTE_PRINTF (3, 0)
+    : gdb_exception (RETURN_ERROR, e, fmt, ap)
+  {
+  }
+
+  explicit gdb_exception_error (gdb_exception &&ex) noexcept
+    : gdb_exception (std::move (ex))
+  {
+    gdb_assert (ex.reason == RETURN_ERROR);
+  }
+};
+
+struct gdb_exception_quit : public gdb_exception
+{
+  gdb_exception_quit (const char *fmt, va_list ap)
+    ATTRIBUTE_PRINTF (2, 0)
+    : gdb_exception (RETURN_QUIT, GDB_NO_ERROR, fmt, ap)
+  {
+  }
+
+  explicit gdb_exception_quit (gdb_exception &&ex) noexcept
+    : gdb_exception (std::move (ex))
+  {
+    gdb_assert (ex.reason == RETURN_QUIT);
+  }
+};
+
+/* An exception type that inherits from both std::bad_alloc and a gdb
+   exception.  This is necessary because operator new can only throw
+   std::bad_alloc, and OTOH, we want exceptions thrown due to memory
+   allocation error to be caught by all the CATCH/RETURN_MASK_ALL
+   spread around the codebase.  */
+
+struct gdb_quit_bad_alloc
+  : public gdb_exception_quit,
+    public std::bad_alloc
+{
+  explicit gdb_quit_bad_alloc (gdb_exception &&ex) noexcept
+    : gdb_exception_quit (std::move (ex)),
+      std::bad_alloc ()
+  {
+  }
+};
+
+/* *INDENT-ON* */
+
+/* Throw an exception (as described by "struct gdb_exception"),
+   landing in the inner most containing exception handler established
+   using TRY/CATCH.  */
+extern void throw_exception (gdb_exception &&exception)
+     ATTRIBUTE_NORETURN;
+
+/* Throw an exception by executing a LONG JUMP to the inner most
+   containing exception handler established using TRY_SJLJ.  Necessary
+   in some cases where we need to throw GDB exceptions across
+   third-party library code (e.g., readline).  */
+extern void throw_exception_sjlj (const struct gdb_exception &exception)
+     ATTRIBUTE_NORETURN;
+
+/* Convenience wrappers around throw_exception that throw GDB
+   errors.  */
+extern void throw_verror (enum errors, const char *fmt, va_list ap)
+     ATTRIBUTE_NORETURN ATTRIBUTE_PRINTF (2, 0);
+extern void throw_vquit (const char *fmt, va_list ap)
+     ATTRIBUTE_NORETURN ATTRIBUTE_PRINTF (1, 0);
+extern void throw_error (enum errors error, const char *fmt, ...)
+     ATTRIBUTE_NORETURN ATTRIBUTE_PRINTF (2, 3);
+extern void throw_quit (const char *fmt, ...)
+     ATTRIBUTE_NORETURN ATTRIBUTE_PRINTF (1, 2);
+
+#endif /* COMMON_COMMON_EXCEPTIONS_H */