From bed418c8bd95178e376251453a136b6dfcbe23e9 Mon Sep 17 00:00:00 2001
From: John Baldwin <jhb@FreeBSD.org>
Date: Sat, 18 Mar 2017 18:10:02 +0000
Subject: [PATCH] Decode the arguments passed to cap_fcntls_get() and
 cap_fcntls_limit().

---
 usr.bin/truss/syscall.h  |  1 +
 usr.bin/truss/syscalls.c | 30 ++++++++++++++++++++++++++++++
 2 files changed, 31 insertions(+)

diff --git a/usr.bin/truss/syscall.h b/usr.bin/truss/syscall.h
index 90b0e8aa94cd..70526de671b6 100644
--- a/usr.bin/truss/syscall.h
+++ b/usr.bin/truss/syscall.h
@@ -45,6 +45,7 @@ enum Argtype { None = 1, Hex, Octal, Int, UInt, LongHex, Name, Ptr, Stat, Ioctl,
 	Pathconf, Rforkflags, ExitStatus, Waitoptions, Idtype, Procctl,
 	LinuxSockArgs, Umtxop, Atfd, Atflags, Timespec2, Accessmode, Long,
 	Sysarch, ExecArgs, ExecEnv, PipeFds, QuadHex, Utrace, IntArray, Pipe2,
+	CapFcntlRights,
 
 	CloudABIAdvice, CloudABIClockID, ClouduABIFDSFlags,
 	CloudABIFDStat, CloudABIFileStat, CloudABIFileType,
diff --git a/usr.bin/truss/syscalls.c b/usr.bin/truss/syscalls.c
index 55e998dbe639..2881b1e4ac0d 100644
--- a/usr.bin/truss/syscalls.c
+++ b/usr.bin/truss/syscalls.c
@@ -92,6 +92,10 @@ static struct syscall decoded_syscalls[] = {
 		    { Int, 3 } } },
 	{ .name = "break", .ret_type = 1, .nargs = 1,
 	  .args = { { Ptr, 0 } } },
+	{ .name = "cap_fcntls_get", .ret_type = 1, .nargs = 2,
+	  .args = { { Int, 0 }, { CapFcntlRights | OUT, 1 } } },
+	{ .name = "cap_fcntls_limit", .ret_type = 1, .nargs = 2,
+	  .args = { { Int, 0 }, { CapFcntlRights, 1 } } },
 	{ .name = "chdir", .ret_type = 1, .nargs = 1,
 	  .args = { { Name, 0 } } },
 	{ .name = "chflags", .ret_type = 1, .nargs = 2,
@@ -791,6 +795,18 @@ print_mask_arg(bool (*decoder)(FILE *, int, int *), FILE *fp, int value)
 		fprintf(fp, "|0x%x", rem);
 }
 
+static void
+print_mask_arg32(bool (*decoder)(FILE *, uint32_t, uint32_t *), FILE *fp,
+    uint32_t value)
+{
+	uint32_t rem;
+
+	if (!decoder(fp, value, &rem))
+		fprintf(fp, "0x%x", rem);
+	else if (rem != 0)
+		fprintf(fp, "|0x%x", rem);
+}
+
 #ifndef __LP64__
 /*
  * Add argument padding to subsequent system calls afater a Quad
@@ -1832,6 +1848,20 @@ print_arg(struct syscall_args *sc, unsigned long *args, long *retval,
 	case Pipe2:
 		print_mask_arg(sysdecode_pipe2_flags, fp, args[sc->offset]);
 		break;
+	case CapFcntlRights: {
+		uint32_t rights;
+
+		if (sc->type & OUT) {
+			if (get_struct(pid, (void *)args[sc->offset], &rights,
+			    sizeof(rights)) == -1) {
+				fprintf(fp, "0x%lx", args[sc->offset]);
+				break;
+			}
+		} else
+			rights = args[sc->offset];
+		print_mask_arg32(sysdecode_cap_fcntlrights, fp, rights);
+		break;
+	}
 
 	case CloudABIAdvice:
 		fputs(xlookup(cloudabi_advice, args[sc->offset]), fp);