gdb/

	* gdbthread.h (currently_stepping): New declaration.
	* infrun.c (currently_stepping): Remove the forward declaration.
	(currently_stepping): Make it global.
	* linux-nat.c (resume_callback) <lp->stopped && lp->status == 0>: New
	variables tp and step, initialized them.  Pass STEP to to_resume.
	Print also possibly "PTRACE_SINGLESTEP" if STEP.  Initialize LP->STEP.
	* remote.c (currently_stepping_callback): New.
	(remote_vcont_resume)
	<ptid_equal (ptid, minus_one_ptid) || ptid_is_pid (ptid)>:
	New variable tp.  Call currently_stepping_callback and step such
	thread.

gdb/testsuite/
	* gdb.threads/sigstep-threads.exp: New file.
	* gdb.threads/sigstep-threads.c: New file.

3 files changed, 133 insertions, 0 deletions

diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index 65a71a9..d48b6d0 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,5 +1,10 @@
 2010-10-17  Jan Kratochvil  <jan.kratochvil@redhat.com>
 
+	* gdb.threads/sigstep-threads.exp: New file.
+	* gdb.threads/sigstep-threads.c: New file.
+
+2010-10-17  Jan Kratochvil  <jan.kratochvil@redhat.com>
+
 	* gdb.base/pie-execl.exp: New file.
 	* gdb.base/pie-execl.c: New file.
 
diff --git a/gdb/testsuite/gdb.threads/sigstep-threads.c b/gdb/testsuite/gdb.threads/sigstep-threads.c
new file mode 100644
index 0000000..7e04c32
--- /dev/null
+++ b/gdb/testsuite/gdb.threads/sigstep-threads.c
@@ -0,0 +1,54 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2010 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 <pthread.h>
+#include <assert.h>
+#include <signal.h>
+
+#include <asm/unistd.h>
+#include <unistd.h>
+#define tgkill(tgid, tid, sig) syscall (__NR_tgkill, (tgid), (tid), (sig))
+#define gettid() syscall (__NR_gettid)
+
+static volatile int var;
+
+static void
+handler (int signo)	/* step-0 */
+{			/* step-0 */
+  var++;		/* step-1 */
+  tgkill (getpid (), gettid (), SIGUSR1);	/* step-2 */
+}
+
+static void *
+start (void *arg)
+{
+  signal (SIGUSR1, handler);
+  tgkill (getpid (), gettid (), SIGUSR1);
+  assert (0);
+
+  return NULL;
+}
+
+int
+main (void)
+{
+  pthread_t thread;
+
+  pthread_create (&thread, NULL, start, NULL);
+  start (NULL);	/* main-start */
+  return 0;
+}
diff --git a/gdb/testsuite/gdb.threads/sigstep-threads.exp b/gdb/testsuite/gdb.threads/sigstep-threads.exp
new file mode 100644
index 0000000..5110706
--- /dev/null
+++ b/gdb/testsuite/gdb.threads/sigstep-threads.exp
@@ -0,0 +1,74 @@
+# Copyright 2010 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/>.
+
+set testfile sigstep-threads
+set srcfile ${testfile}.c
+set executable ${testfile}
+set binfile ${objdir}/${subdir}/${executable}
+
+if { [gdb_compile_pthreads "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug}] != "" } {
+    untested ${testfile}.exp
+    return -1
+}
+
+clean_restart $executable
+
+if ![runto_main] {
+    return -1;
+}
+
+# `noprint' would not test the full logic of GDB.
+gdb_test "handle SIGUSR1 nostop print pass" "\r\nSIGUSR1\[ \t\]+No\[ \t\]+Yes\[ \t\]+Yes\[ \t\].*"
+
+gdb_test_no_output "set scheduler-locking off"
+
+gdb_breakpoint [gdb_get_line_number "step-1"]
+gdb_test_no_output {set $step1=$bpnum}
+gdb_continue_to_breakpoint "step-1" ".* step-1 .*"
+gdb_test_no_output {disable $step1}
+
+# 1 as we are now stopped at the `step-1' label.
+set step_at 1
+for {set i 0} {$i < 100} {incr i} {
+    set test "step $i"
+    # Presume this step failed - as in the case of a timeout.
+    set failed 1
+    gdb_test_multiple "step" $test {
+	-re "\r\nProgram received signal SIGUSR1, User defined signal 1.\r\n" {
+	    exp_continue -continue_timer
+	}
+	-re "step-(\[012\]).*\r\n$gdb_prompt $" {
+	    set now $expect_out(1,string)
+	    if {$step_at == 2 && $now == 1} {
+		set failed 0
+	    } elseif {$step_at == 1 && $now == 2} {
+		set failed 0
+		# Continue over the re-signalling back to the handle entry.
+		gdb_test_no_output {enable $step1} ""
+		gdb_test "continue" " step-1 .*" ""
+		set now 1
+		gdb_test_no_output {disable $step1} ""
+	    } else  {
+		fail $test
+	    }
+	    set step_at $now
+	}
+    }
+    if $failed {
+	return
+    }
+}
+# We can never reliably say the racy problematic case has been tested.
+pass "step"