[PATCH 1/3] sim: callback: add a getpid interface

[PATCH 1/3] sim: callback: add a getpid interface

[Mike Frysinger]

Rather than hit the OS interface directly, use the existing callback
layer so the instantiator can decide behavior.
---
 include/sim/callback.h |  1 +
 sim/common/callback.c  | 13 +++++++++++++
 sim/common/syscall.c   |  3 ++-
 3 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/include/sim/callback.h b/include/sim/callback.h
index 4c162bc145ea..a6c536b1be1c 100644
--- a/include/sim/callback.h
+++ b/include/sim/callback.h
@@ -91,6 +91,7 @@ struct host_callback_struct
   int (*to_lstat) (host_callback *, const char *, struct stat *);
   int (*ftruncate) (host_callback *, int, int64_t);
   int (*truncate) (host_callback *, const char *, int64_t);
+  int (*getpid) (host_callback *);
   int (*pipe) (host_callback *, int *);
 
   /* Called by the framework when a read call has emptied a pipe buffer.  */
diff --git a/sim/common/callback.c b/sim/common/callback.c
index f2587a452540..071e7b149b97 100644
--- a/sim/common/callback.c
+++ b/sim/common/callback.c
@@ -556,6 +556,17 @@ os_truncate (host_callback *p, const char *file, int64_t len)
 #endif
 }
 
+static int
+os_getpid (host_callback *p)
+{
+  int result;
+
+  result = getpid ();
+  /* POSIX says getpid always succeeds.  */
+  p->last_errno = 0;
+  return result;
+}
+
 static int
 os_pipe (host_callback *p, int *filedes)
 {
@@ -737,6 +748,8 @@ host_callback default_callback =
   os_ftruncate,
   os_truncate,
 
+  os_getpid,
+
   os_pipe,
   os_pipe_empty,
   os_pipe_nonempty,
diff --git a/sim/common/syscall.c b/sim/common/syscall.c
index 4e76d2008a30..7ef34b95e9cf 100644
--- a/sim/common/syscall.c
+++ b/sim/common/syscall.c
@@ -579,7 +579,8 @@ cb_syscall (host_callback *cb, CB_SYSCALL *sc)
       break;
 
     case CB_SYS_getpid:
-      result = getpid ();
+      /* POSIX says getpid always succeeds.  */
+      result = (*cb->getpid) (cb);
       break;
 
     case CB_SYS_time :
-- 
2.31.1

[PATCH 2/3] sim: callback: generate signal map

[Mike Frysinger]

We've been generating the syscall/errno/open maps, but not the signal
map, even though we've been including them in the source constants.
---
 sim/common/callback.c |  3 +++
 sim/common/gentmap.c  | 24 ++++++++++++++++++++++++
 2 files changed, 27 insertions(+)

diff --git a/sim/common/callback.c b/sim/common/callback.c
index 071e7b149b97..aca0112853c4 100644
--- a/sim/common/callback.c
+++ b/sim/common/callback.c
@@ -32,6 +32,7 @@
 #include <limits.h>
 #include <errno.h>
 #include <fcntl.h>
+#include <signal.h>
 #include <time.h>
 #include <sys/types.h>
 #include <sys/stat.h>
@@ -56,6 +57,7 @@ void sim_cb_eprintf (host_callback *, const char *, ...);
 
 extern CB_TARGET_DEFS_MAP cb_init_syscall_map[];
 extern CB_TARGET_DEFS_MAP cb_init_errno_map[];
+extern CB_TARGET_DEFS_MAP cb_init_signal_map[];
 extern CB_TARGET_DEFS_MAP cb_init_open_map[];
 
 /* Make sure the FD provided is ok.  If not, return non-zero
@@ -676,6 +678,7 @@ os_init (host_callback *p)
 
   p->syscall_map = cb_init_syscall_map;
   p->errno_map = cb_init_errno_map;
+  p->signal_map = cb_init_signal_map;
   p->open_map = cb_init_open_map;
 
   return 1;
diff --git a/sim/common/gentmap.c b/sim/common/gentmap.c
index 254ec3f11195..f1f1bc2c03f3 100644
--- a/sim/common/gentmap.c
+++ b/sim/common/gentmap.c
@@ -23,6 +23,13 @@ static struct tdefs errno_tdefs[] =  {
   { 0, 0 }
 };
 
+static struct tdefs signal_tdefs[] = {
+#define signal_defs
+#include "nltvals.def"
+#undef signal_defs
+  { 0, 0 }
+};
+
 static struct tdefs open_tdefs[] = {
 #define open_defs
 #include "nltvals.def"
@@ -51,6 +58,11 @@ gen_targ_vals_h (void)
     printf ("#define TARGET_%s %d\n", t->symbol, t->value);
   printf ("\n");
 
+  printf ("/* signal values */\n");
+  for (t = &signal_tdefs[0]; t->symbol; ++t)
+    printf ("#define TARGET_%s %d\n", t->symbol, t->value);
+  printf ("\n");
+
   printf ("/* open flag values */\n");
   for (t = &open_tdefs[0]; t->symbol; ++t)
     printf ("#define TARGET_%s 0x%x\n", t->symbol, t->value);
@@ -70,6 +82,7 @@ gen_targ_map_c (void)
   printf ("#include \"defs.h\"\n");
   printf ("#include <errno.h>\n");
   printf ("#include <fcntl.h>\n");
+  printf ("#include <signal.h>\n");
   printf ("#include \"ansidecl.h\"\n");
   printf ("#include \"sim/callback.h\"\n");
   printf ("#include \"targ-vals.h\"\n");
@@ -98,6 +111,17 @@ gen_targ_map_c (void)
   printf ("  { 0, 0, 0 }\n");
   printf ("};\n\n");
 
+  printf ("/* signals mapping table */\n");
+  printf ("CB_TARGET_DEFS_MAP cb_init_signal_map[] = {\n");
+  for (t = &signal_tdefs[0]; t->symbol; ++t)
+    {
+      printf ("#ifdef %s\n", t->symbol);
+      printf ("  { \"%s\", %s, TARGET_%s },\n", t->symbol, t->symbol, t->symbol);
+      printf ("#endif\n");
+    }
+  printf ("  { 0, -1, -1 }\n");
+  printf ("};\n\n");
+
   printf ("/* open flags mapping table */\n");
   printf ("CB_TARGET_DEFS_MAP cb_init_open_map[] = {\n");
   for (t = &open_tdefs[0]; t->symbol; ++t)
-- 
2.31.1

[PATCH 3/3] sim: callback: add missing cb_target_to_host_signal

[Mike Frysinger]

There's been a prototype for this forever, but the implementation was
missing.  Probably because there weren't any callers, but we'll start
using it to implement the kill function.
---
 sim/common/callback.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/sim/common/callback.c b/sim/common/callback.c
index aca0112853c4..06d76b477245 100644
--- a/sim/common/callback.c
+++ b/sim/common/callback.c
@@ -927,6 +927,19 @@ cb_target_to_host_open (host_callback *cb, int target_val)
   return host_val;
 }
 
+/* Translate the target's version of a signal number to the host's.
+   This isn't actually the host's version, rather a canonical form.
+   ??? Perhaps this should be renamed to ..._canon_signal.  */
+
+int
+cb_target_to_host_signal (host_callback *cb, int target_val)
+{
+  const CB_TARGET_DEFS_MAP *m =
+    cb_target_map_entry (cb->signal_map, target_val);
+
+  return m ? m->host_val : -1;
+}
+
 /* Utility for e.g. cb_host_to_target_stat to store values in the target's
    stat struct.
 
-- 
2.31.1

Re: [PATCH 1/3] sim: callback: add a getpid interface

[Christian Biesinger]

On Sun, Jun 20, 2021 at 10:55 PM Mike Frysinger via Gdb-patches
<gdb-patches@sourceware.org> wrote:
> --- a/sim/common/callback.c
> +++ b/sim/common/callback.c
> @@ -556,6 +556,17 @@ os_truncate (host_callback *p, const char *file, int64_t len)
>  #endif
>  }
>
> +static int
> +os_getpid (host_callback *p)
> +{
> +  int result;
> +
> +  result = getpid ();

sim is C11, right? Why not write this as "int result = getpid ();"?

Christian

Re: [PATCH 1/3] sim: callback: add a getpid interface

[Mike Frysinger]

On 21 Jun 2021 17:58, Christian Biesinger wrote:
> On Sun, Jun 20, 2021 at 10:55 PM Mike Frysinger wrote:
> > --- a/sim/common/callback.c
> > +++ b/sim/common/callback.c
> > @@ -556,6 +556,17 @@ os_truncate (host_callback *p, const char *file, int64_t len)
> >  #endif
> >  }
> >
> > +static int
> > +os_getpid (host_callback *p)
> > +{
> > +  int result;
> > +
> > +  result = getpid ();
> 
> sim is C11, right? Why not write this as "int result = getpid ();"?

just maintaining copy & paste style in this module, and because (iiuc), GNU
style wants a blank line after decls.  so imo it looks nicer to have business
logic grouped together.

{
  int result = getpid ();

  p->last_errno = errno;
  return result;
}

{
  int result;
  
  result = getpid ();
  p->last_errno = errno;
  return result;
}
-mike