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+/* Native-dependent code for FreeBSD/i386.
+ Copyright 2001 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 2 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, write to the Free Software
+ Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
+
+#include "defs.h"
+#include "inferior.h"
+#include "regcache.h"
+
+#include <sys/types.h>
+#include <sys/ptrace.h>
+#include <sys/sysctl.h>
+
+/* Prevent warning from -Wmissing-prototypes. */
+void _initialize_i386fbsd_nat (void);
+
+/* Resume execution of the inferior process.
+ If STEP is nonzero, single-step it.
+ If SIGNAL is nonzero, give it that signal. */
+
+void
+child_resume (ptid_t ptid, int step, enum target_signal signal)
+{
+ pid_t pid = ptid_get_pid (ptid);
+ int request = PT_STEP;
+
+ if (pid == -1)
+ /* Resume all threads. This only gets used in the non-threaded
+ case, where "resume all threads" and "resume inferior_ptid" are
+ the same. */
+ pid = ptid_get_pid (inferior_ptid);
+
+ if (!step)
+ {
+ unsigned int eflags;
+
+ /* Workaround for a bug in FreeBSD. Make sure that the trace
+ flag is off when doing a continue. There is a code path
+ through the kernel which leaves the flag set when it should
+ have been cleared. If a process has a signal pending (such
+ as SIGALRM) and we do a PT_STEP, the process never really has
+ a chance to run because the kernel needs to notify the
+ debugger that a signal is being sent. Therefore, the process
+ never goes through the kernel's trap() function which would
+ normally clear it. */
+
+ eflags = read_register (PS_REGNUM);
+ if (eflags & 0x0100)
+ write_register (PS_REGNUM, eflags & ~0x0100);
+
+ request = PT_CONTINUE;
+ }
+
+ /* An addres of (caddr_t) 1 tells ptrace to continue from where it
+ was. (If GDB wanted it to start some other way, we have already
+ written a new PC value to the child.) */
+ if (ptrace (request, pid, (caddr_t) 1,
+ target_signal_to_host (signal)) == -1)
+ perror_with_name ("ptrace");
+}
+
+void
+_initialize_i386fbsd_nat (void)
+{
+ /* FreeBSD provides a kern.ps_strings sysctl that we can use to
+ locate the sigtramp. That way we can still recognize a sigtramp
+ if it's location is changed in a new kernel. Of course this is
+ still based on the assumption that the sigtramp is placed
+ directly under the location where the program arguments and
+ environment can be found. */
+#ifdef KERN_PS_STRINGS
+ {
+ int mib[2];
+ int ps_strings;
+ size_t len;
+
+ mib[0] = CTL_KERN;
+ mib[1] = KERN_PS_STRINGS;
+ len = sizeof (ps_strings);
+ if (sysctl (mib, 2, &ps_strings, &len, NULL, 0) == 0)
+ {
+ i386bsd_sigtramp_start = ps_strings - 128;
+ i386bsd_sigtramp_end = ps_strings;
+ }
+ }
+#endif
+}