[binutils-gdb] sim: callback: add a kill interface

[Michael Frysinger]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=d394a6efed4723b86f8e4f09fc23f6d03a7ad835

commit d394a6efed4723b86f8e4f09fc23f6d03a7ad835
Author: Mike Frysinger <vapier@gentoo.org>
Date:   Sun Jun 20 23:06:10 2021 -0400

    sim: callback: add a kill interface
    
    This will make it easier to emulate the syscall.  If the kill target
    is the sim itself, don't do anything.  This forces the higher layers
    to make a decision as to how to handle this event: like halting the
    overall engine process.

Diff:
---
 include/sim/ChangeLog  |  4 ++++
 include/sim/callback.h |  1 +
 sim/common/ChangeLog   |  6 ++++++
 sim/common/callback.c  | 11 +++++++++++
 sim/common/syscall.c   | 18 ++++++++++++++++++
 5 files changed, 40 insertions(+)

diff --git a/include/sim/ChangeLog b/include/sim/ChangeLog
index b98631b37e5..3faea582894 100644
--- a/include/sim/ChangeLog
+++ b/include/sim/ChangeLog
@@ -1,3 +1,7 @@
+2021-06-23  Mike Frysinger  <vapier@gentoo.org>
+
+	* sim/callback.h (struct host_callback_struct): Add kill.
+
 2021-06-22  Mike Frysinger  <vapier@gentoo.org>
 
 	* sim/callback.h (struct host_callback_struct): Add getpid.
diff --git a/include/sim/callback.h b/include/sim/callback.h
index a6c536b1be1..8d61ebb879e 100644
--- a/include/sim/callback.h
+++ b/include/sim/callback.h
@@ -92,6 +92,7 @@ struct host_callback_struct
   int (*ftruncate) (host_callback *, int, int64_t);
   int (*truncate) (host_callback *, const char *, int64_t);
   int (*getpid) (host_callback *);
+  int (*kill) (host_callback *, int, int);
   int (*pipe) (host_callback *, int *);
 
   /* Called by the framework when a read call has emptied a pipe buffer.  */
diff --git a/sim/common/ChangeLog b/sim/common/ChangeLog
index bb1a967c298..c32e7475a80 100644
--- a/sim/common/ChangeLog
+++ b/sim/common/ChangeLog
@@ -1,3 +1,9 @@
+2021-06-23  Mike Frysinger  <vapier@gentoo.org>
+
+	* callback.c (os_kill): New function.
+	(default_callback): Add os_kill.
+	* syscall.c (cb_syscall): Handle CB_SYS_kill.
+
 2021-06-23  Mike Frysinger  <vapier@gentoo.org>
 
 	* Make-common.in (srcdir): Change to abs_srcdir.
diff --git a/sim/common/callback.c b/sim/common/callback.c
index 06d76b47724..c0ace6e4c8e 100644
--- a/sim/common/callback.c
+++ b/sim/common/callback.c
@@ -569,6 +569,16 @@ os_getpid (host_callback *p)
   return result;
 }
 
+static int
+os_kill (host_callback *p, int pid, int signum)
+{
+  int result;
+
+  result = kill (pid, signum);
+  p->last_errno = errno;
+  return result;
+}
+
 static int
 os_pipe (host_callback *p, int *filedes)
 {
@@ -752,6 +762,7 @@ host_callback default_callback =
   os_truncate,
 
   os_getpid,
+  os_kill,
 
   os_pipe,
   os_pipe_empty,
diff --git a/sim/common/syscall.c b/sim/common/syscall.c
index 7ef34b95e9c..6efddcfecde 100644
--- a/sim/common/syscall.c
+++ b/sim/common/syscall.c
@@ -583,6 +583,24 @@ cb_syscall (host_callback *cb, CB_SYSCALL *sc)
       result = (*cb->getpid) (cb);
       break;
 
+    case CB_SYS_kill:
+      /* If killing self, leave it to the caller to process so it can send the
+	 signal to the engine.  */
+      if (sc->arg1 == (*cb->getpid) (cb))
+	{
+	  result = -1;
+	  errcode = ENOSYS;
+	}
+      else
+	{
+	  int signum = cb_target_to_host_signal (cb, sc->arg2);
+
+	  result = (*cb->kill) (cb, sc->arg1, signum);
+	  cb->last_errno = errno;
+	  goto ErrorFinish;
+	}
+      break;
+
     case CB_SYS_time :
       {
 	/* FIXME: May wish to change CB_SYS_time to something else.