[PATCH v3 09/29] Share Windows thread-suspend and -resume code

Tom Tromey
2020-03-13T19:09:00Z

This adds "suspend" and "resume" methods to windows_thread_info, and
changes gdb and gdbserver to share this code.

gdb/ChangeLog
2020-03-13 Tom Tromey <tromey@adacore.com>

* windows-nat.c (thread_rec): Use windows_thread_info::suspend.
(windows_continue): Use windows_continue::resume.
* nat/windows-nat.h (struct windows_thread_info) <suspend,
resume>: Declare new methods.
* nat/windows-nat.c: New file.
* configure.nat (NATDEPFILES): Add nat/windows-nat.o when needed.

gdbserver/ChangeLog
2020-03-13 Tom Tromey <tromey@adacore.com>

* win32-low.c (win32_require_context, suspend_one_thread): Use
windows_thread_info::suspend.
(continue_one_thread): Use windows_thread_info::resume.
* configure.srv (srv_tgtobj): Add windows-nat.o when needed.
---
gdb/ChangeLog | 9 +++++++
gdb/configure.nat | 4 +--
gdb/nat/windows-nat.c | 60 +++++++++++++++++++++++++++++++++++++++++
gdb/nat/windows-nat.h | 6 +++++
gdb/windows-nat.c | 26 ++----------------
gdbserver/ChangeLog | 7 +++++
gdbserver/configure.srv | 7 ++++-
gdbserver/win32-low.cc | 33 +++--------------------
8 files changed, 95 insertions(+), 57 deletions(-)
create mode 100644 gdb/nat/windows-nat.c

diff --git a/gdb/configure.nat b/gdb/configure.nat
index 83ffdb80486..6ea25834954 100644
--- a/gdb/configure.nat
+++ b/gdb/configure.nat
@@ -75,10 +75,10 @@ case ${gdb_host} in
NATDEPFILES='fork-child.o nat/fork-inferior.o inf-ptrace.o'
;;
cygwin*)
- NATDEPFILES='x86-nat.o nat/x86-dregs.o windows-nat.o'
+ NATDEPFILES='x86-nat.o nat/x86-dregs.o windows-nat.o nat/windows-nat.o'
;;
mingw*)
- NATDEPFILES='x86-nat.o nat/x86-dregs.o windows-nat.o'
+ NATDEPFILES='x86-nat.o nat/x86-dregs.o windows-nat.o nat/windows-nat.o'
;;
aix)
NATDEPFILES='nat/fork-inferior.o fork-child.o inf-ptrace.o'
diff --git a/gdb/nat/windows-nat.c b/gdb/nat/windows-nat.c
new file mode 100644
index 00000000000..a98ff421e6f
--- /dev/null
+++ b/gdb/nat/windows-nat.c
@@ -0,0 +1,60 @@
+/* Internal interfaces for the Windows code
+ Copyright (C) 1995-2019 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/>. */
+
+#include "gdbsupport/common-defs.h"
+#include "nat/windows-nat.h"
+
+void
+windows_thread_info::suspend ()
+{
+ if (suspended != 0)
+ return;
+
+ if (SuspendThread (h) == (DWORD) -1)
+ {
+ DWORD err = GetLastError ();
+
+ /* We get Access Denied (5) when trying to suspend
+ threads that Windows started on behalf of the
+ debuggee, usually when those threads are just
+ about to exit.
+ We can get Invalid Handle (6) if the main thread
+ has exited. */
+ if (err != ERROR_INVALID_HANDLE && err != ERROR_ACCESS_DENIED)
+ warning (_("SuspendThread (tid=0x%x) failed. (winerr %u)"),
+ (unsigned) tid, (unsigned) err);
+ suspended = -1;
+ }
+ else
+ suspended = 1;
+}
+
+void
+windows_thread_info::resume ()
+{
+ if (suspended > 0)
+ {
+ if (ResumeThread (h) == (DWORD) -1)
+ {
+ DWORD err = GetLastError ();
+ warning (_("warning: ResumeThread (tid=0x%x) failed. (winerr %u)"),
+ (unsigned) tid, (unsigned) err);
+ }
+ }
+ suspended = 0;
+}
diff --git a/gdb/nat/windows-nat.h b/gdb/nat/windows-nat.h
index 543de895e77..695f801c58f 100644
--- a/gdb/nat/windows-nat.h
+++ b/gdb/nat/windows-nat.h
@@ -34,6 +34,12 @@ struct windows_thread_info

DISABLE_COPY_AND_ASSIGN (windows_thread_info);

+ /* Ensure that this thread has been suspended. */
+ void suspend ();
+
+ /* Resume the thread if it has been suspended. */
+ void resume ();
+
/* The Win32 thread identifier. */
DWORD tid;

diff --git a/gdb/windows-nat.c b/gdb/windows-nat.c
index 155682ba107..ce83da0ff9f 100644
--- a/gdb/windows-nat.c
+++ b/gdb/windows-nat.c
@@ -416,27 +416,7 @@ thread_rec (DWORD id, int get_context)
if (!th->suspended && get_context)
{
if (get_context > 0 && id != current_event.dwThreadId)
- {
- if (SuspendThread (th->h) == (DWORD) -1)
- {
- DWORD err = GetLastError ();
-
- /* We get Access Denied (5) when trying to suspend
- threads that Windows started on behalf of the
- debuggee, usually when those threads are just
- about to exit.
- We can get Invalid Handle (6) if the main thread
- has exited. */
- if (err != ERROR_INVALID_HANDLE
- && err != ERROR_ACCESS_DENIED)
- warning (_("SuspendThread (tid=0x%x) failed."
- " (winerr %u)"),
- (unsigned) id, (unsigned) err);
- th->suspended = -1;
- }
- else
- th->suspended = 1;
- }
+ th->suspend ();
else if (get_context < 0)
th->suspended = -1;
th->reload_context = true;
@@ -1515,9 +1495,7 @@ windows_continue (DWORD continue_status, int id, int killed)
th->context.ContextFlags = 0;
}
}
- if (th->suspended > 0)
- (void) ResumeThread (th->h);
- th->suspended = 0;
+ th->resume ();
}

res = ContinueDebugEvent (current_event.dwProcessId,
diff --git a/gdbserver/configure.srv b/gdbserver/configure.srv
index ecdd63a310a..7acf229fbef 100644
--- a/gdbserver/configure.srv
+++ b/gdbserver/configure.srv
@@ -74,7 +74,7 @@ case "${gdbserver_host}" in
srv_linux_thread_db=yes
;;
arm*-*-mingw32ce*) srv_regobj=reg-arm.o
- srv_tgtobj="win32-low.o win32-arm-low.o"
+ srv_tgtobj="win32-low.o windows-nat.o win32-arm-low.o"
srv_tgtobj="${srv_tgtobj} wincecompat.o"
# hostio_last_error implementation is in win32-low.c
srv_hostio_err_objs=""
@@ -99,6 +99,7 @@ case "${gdbserver_host}" in
i[34567]86-*-cygwin*) srv_regobj=""
srv_tgtobj="x86-low.o nat/x86-dregs.o win32-low.o"
srv_tgtobj="${srv_tgtobj} win32-i386-low.o"
+ srv_tgtobj="${srv_tgtobj} nat/windows-nat.o"
srv_tgtobj="${srv_tgtobj} arch/i386.o"
;;
i[34567]86-*-linux*) srv_tgtobj="${srv_tgtobj} arch/i386.o"
@@ -126,6 +127,7 @@ case "${gdbserver_host}" in
srv_regobj=""
srv_tgtobj="x86-low.o nat/x86-dregs.o win32-low.o"
srv_tgtobj="${srv_tgtobj} win32-i386-low.o"
+ srv_tgtobj="${srv_tgtobj} nat/windows-nat.o"
srv_tgtobj="${srv_tgtobj} arch/i386.o"
srv_tgtobj="${srv_tgtobj} wincecompat.o"
# hostio_last_error implementation is in win32-low.c
@@ -136,6 +138,7 @@ case "${gdbserver_host}" in
i[34567]86-*-mingw*) srv_regobj=""
srv_tgtobj="x86-low.o nat/x86-dregs.o win32-low.o"
srv_tgtobj="${srv_tgtobj} win32-i386-low.o"
+ srv_tgtobj="${srv_tgtobj} nat/windows-nat.o"
srv_tgtobj="${srv_tgtobj} arch/i386.o"
srv_mingw=yes
;;
@@ -393,12 +396,14 @@ case "${gdbserver_host}" in
x86_64-*-mingw*) srv_regobj=""
srv_tgtobj="x86-low.o nat/x86-dregs.o i387-fp.o"
srv_tgtobj="${srv_tgtobj} win32-low.o win32-i386-low.o"
+ srv_tgtobj="${srv_tgtobj} nat/windows-nat.o"
srv_tgtobj="${srv_tgtobj} arch/amd64.o"
srv_mingw=yes
;;
x86_64-*-cygwin*) srv_regobj=""
srv_tgtobj="x86-low.o nat/x86-dregs.o i387-fp.o"
srv_tgtobj="${srv_tgtobj} win32-low.o win32-i386-low.o"
+ srv_tgtobj="${srv_tgtobj} nat/windows-nat.o"
srv_tgtobj="${srv_tgtobj} arch/amd64.o"
;;

diff --git a/gdbserver/win32-low.cc b/gdbserver/win32-low.cc
index 1284ed177cb..7cad640878f 100644
--- a/gdbserver/win32-low.cc
+++ b/gdbserver/win32-low.cc
@@ -171,18 +171,7 @@ win32_require_context (windows_thread_info *th)
{
if (th->context.ContextFlags == 0)
{
- if (!th->suspended)
- {
- if (SuspendThread (th->h) == (DWORD) -1)
- {
- DWORD err = GetLastError ();
- OUTMSG (("warning: SuspendThread failed in thread_rec, "
- "(error %d): %s\n", (int) err, strwinerror (err)));
- }
- else
- th->suspended = 1;
- }
-
+ th->suspend ();
win32_get_thread_context (th);
}
}
@@ -435,13 +424,7 @@ continue_one_thread (thread_info *thread, int thread_id)
th->context.ContextFlags = 0;
}

- if (ResumeThread (th->h) == (DWORD) -1)
- {
- DWORD err = GetLastError ();
- OUTMSG (("warning: ResumeThread failed in continue_one_thread, "
- "(error %d): %s\n", (int) err, strwinerror (err)));
- }
- th->suspended = 0;
+ th->resume ();
}
}
}
@@ -1348,17 +1331,7 @@ suspend_one_thread (thread_info *thread)
{
windows_thread_info *th = (windows_thread_info *) thread_target_data (thread);

- if (!th->suspended)
- {
- if (SuspendThread (th->h) == (DWORD) -1)
- {
- DWORD err = GetLastError ();
- OUTMSG (("warning: SuspendThread failed in suspend_one_thread, "
- "(error %d): %s\n", (int) err, strwinerror (err)));
- }
- else
- th->suspended = 1;
- }
+ th->suspend ();
}

static void
--
2.21.1