svn commit: r339840 - head/usr.bin/truss

[Thomas Munro]

Author: tmunro
Date: Sun Oct 28 10:59:49 2018
New Revision: 339840
URL: https://svnweb.freebsd.org/changeset/base/339840

Log:
  truss: Fix display of shm_open(SHM_ANON, ...).
  
  Currently truss(1) shows shm_open(SHM_ANON, ...) as shm_open("(null)", ...).
  Detect the special value and display it by name.
  
  Reviewed by:    jhb, allanjude, tuexen
  Approved by:    mjg (mentor)
  MFC with:       r339224
  Differential Revision:  https://reviews.freebsd.org/D17461

Modified:
  head/usr.bin/truss/syscall.h
  head/usr.bin/truss/syscalls.c

Modified: head/usr.bin/truss/syscall.h
==============================================================================
--- head/usr.bin/truss/syscall.h	Sun Oct 28 07:50:15 2018	(r339839)
+++ head/usr.bin/truss/syscall.h	Sun Oct 28 10:59:49 2018	(r339840)
@@ -151,6 +151,7 @@ enum Argtype {
 	PQuadHex,
 	PUInt,
 	Readlinkres,
+	ShmName,
 	StringArray,
 
 	/* Pointers to structures. */

Modified: head/usr.bin/truss/syscalls.c
==============================================================================
--- head/usr.bin/truss/syscalls.c	Sun Oct 28 07:50:15 2018	(r339839)
+++ head/usr.bin/truss/syscalls.c	Sun Oct 28 10:59:49 2018	(r339840)
@@ -44,6 +44,7 @@ __FBSDID("$FreeBSD$");
 #define	_WANT_FREEBSD11_KEVENT
 #include <sys/event.h>
 #include <sys/ioccom.h>
+#include <sys/mman.h>
 #include <sys/mount.h>
 #include <sys/ptrace.h>
 #include <sys/resource.h>
@@ -462,7 +463,7 @@ static struct syscall decoded_syscalls[] = {
 	  .args = { { Int, 0 }, { Sockoptlevel, 1 }, { Sockoptname, 2 },
 		    { Ptr | IN, 3 }, { Socklent, 4 } } },
 	{ .name = "shm_open", .ret_type = 1, .nargs = 3,
-	  .args = { { Name | IN, 0 }, { Open, 1 }, { Octal, 2 } } },
+	  .args = { { ShmName | IN, 0 }, { Open, 1 }, { Octal, 2 } } },
 	{ .name = "shm_unlink", .ret_type = 1, .nargs = 1,
 	  .args = { { Name | IN, 0 } } },
 	{ .name = "shutdown", .ret_type = 1, .nargs = 2,
@@ -1593,6 +1594,13 @@ print_arg(struct syscall_args *sc, unsigned long *args
 	case Sizet:
 		fprintf(fp, "%zu", (size_t)args[sc->offset]);
 		break;
+	case ShmName:
+		/* Handle special SHM_ANON value. */
+		if ((char *)args[sc->offset] == SHM_ANON) {
+			fprintf(fp, "SHM_ANON");
+			break;
+		}
+		/* FALLTHROUGH */
 	case Name: {
 		/* NULL-terminated string. */
 		char *tmp2;