From ebb2cc40d1f62e204166a72f9141416c16c11210 Mon Sep 17 00:00:00 2001
From: John Baldwin <jhb@FreeBSD.org>
Date: Fri, 2 Jun 2017 22:35:18 +0000
Subject: [PATCH] Decode the argument passed to cap_getmode().

The returned integer value is output.
---
 usr.bin/truss/syscall.h  |  2 +-
 usr.bin/truss/syscalls.c | 12 ++++++++++++
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/usr.bin/truss/syscall.h b/usr.bin/truss/syscall.h
index f0b39b468bbf..6c6babb5b241 100644
--- a/usr.bin/truss/syscall.h
+++ b/usr.bin/truss/syscall.h
@@ -48,7 +48,7 @@ enum Argtype { None = 1, Hex, Octal, Int, UInt, LongHex, Name, Ptr, Stat, Ioctl,
 	Sysarch, ExecArgs, ExecEnv, PipeFds, QuadHex, Utrace, IntArray, Pipe2,
 	CapFcntlRights, Fadvice, FileFlags, Flockop, Getfsstatmode, Kldsymcmd,
 	Kldunloadflags, Sizet, Madvice, Socklent, Sockprotocol, Sockoptlevel,
-	Sockoptname, Msgflags, CapRights,
+	Sockoptname, Msgflags, CapRights, PUInt,
 
 	CloudABIAdvice, CloudABIClockID, ClouduABIFDSFlags,
 	CloudABIFDStat, CloudABIFileStat, CloudABIFileType,
diff --git a/usr.bin/truss/syscalls.c b/usr.bin/truss/syscalls.c
index f8c1943125ec..f4195642276d 100644
--- a/usr.bin/truss/syscalls.c
+++ b/usr.bin/truss/syscalls.c
@@ -99,6 +99,8 @@ static struct syscall decoded_syscalls[] = {
 	  .args = { { Int, 0 }, { CapFcntlRights | OUT, 1 } } },
 	{ .name = "cap_fcntls_limit", .ret_type = 1, .nargs = 2,
 	  .args = { { Int, 0 }, { CapFcntlRights, 1 } } },
+	{ .name = "cap_getmode", .ret_type = 1, .nargs = 1,
+	  .args = { { PUInt | OUT, 0 } } },
 	{ .name = "cap_rights_limit", .ret_type = 1, .nargs = 2,
 	  .args = { { Int, 0 }, { CapRights, 1 } } },
 	{ .name = "chdir", .ret_type = 1, .nargs = 1,
@@ -1190,6 +1192,16 @@ print_arg(struct syscall_args *sc, unsigned long *args, long *retval,
 	case UInt:
 		fprintf(fp, "%u", (unsigned int)args[sc->offset]);
 		break;
+	case PUInt: {
+		unsigned int val;
+
+		if (get_struct(pid, (void *)args[sc->offset], &val,
+		    sizeof(val)) == 0) 
+			fprintf(fp, "{ %u }", val);
+		else
+			fprintf(fp, "0x%lx", args[sc->offset]);
+		break;
+	}
 	case LongHex:
 		fprintf(fp, "0x%lx", args[sc->offset]);
 		break;