From 2b9a971a717f928c61eaec9178173d1a57b91601 Mon Sep 17 00:00:00 2001
From: Etienne Perot <eperot@google.com>
Date: Thu, 30 Mar 2023 10:27:06 -0700
Subject: [PATCH] Expand `test_app syscall` to support syscall arguments.

PiperOrigin-RevId: 520677631
---
 test/cmd/test_app/main.go | 38 +++++++++++++++++++++++++++++++++-----
 test/util/BUILD           | 10 +++++-----
 2 files changed, 38 insertions(+), 10 deletions(-)

diff --git a/test/cmd/test_app/main.go b/test/cmd/test_app/main.go
index 092221fff..179578b29 100644
--- a/test/cmd/test_app/main.go
+++ b/test/cmd/test_app/main.go
@@ -29,6 +29,7 @@ import (
 	"path/filepath"
 	"regexp"
 	"strconv"
+	"strings"
 	sys "syscall"
 	"time"
 
@@ -338,7 +339,7 @@ func (*syscall) Synopsis() string {
 
 // Usage implements subcommands.Command.
 func (*syscall) Usage() string {
-	return "syscall <flags>"
+	return "syscall <flags> [arg1 arg2...]"
 }
 
 // SetFlags implements subcommands.Command.
@@ -347,11 +348,38 @@ func (s *syscall) SetFlags(f *flag.FlagSet) {
 }
 
 // Execute implements subcommands.Command.
-func (s *syscall) Execute(ctx context.Context, f *flag.FlagSet, args ...any) subcommands.ExitStatus {
-	if _, _, errno := sys.Syscall(uintptr(s.sysno), 0, 0, 0); errno != 0 {
-		fmt.Printf("syscall(%d, 0, 0...) failed: %v\n", s.sysno, errno)
+func (s *syscall) Execute(ctx context.Context, f *flag.FlagSet, _ ...any) subcommands.ExitStatus {
+	const maxSyscallArgs = 6
+	numArgs := f.NArg()
+	if numArgs > maxSyscallArgs {
+		fmt.Printf("number of sycall arguments not supported: %d (max is %d)\n", numArgs, maxSyscallArgs)
+		return subcommands.ExitUsageError
+	}
+	var syscallArgs [maxSyscallArgs]uintptr
+	for i := 0; i < numArgs; i++ {
+		uintArg, err := strconv.ParseUint(f.Arg(i), 10, 64)
+		if err != nil {
+			fmt.Printf("not an integer: %q\n", f.Arg(i))
+			return subcommands.ExitUsageError
+		}
+		syscallArgs[i] = uintptr(uintArg)
+	}
+	var errno sys.Errno
+	switch numArgs {
+	case 0:
+		_, _, errno = sys.Syscall(uintptr(s.sysno), 0, 0, 0)
+	case 3:
+		_, _, errno = sys.Syscall(uintptr(s.sysno), syscallArgs[0], syscallArgs[1], syscallArgs[2])
+	case 6:
+		_, _, errno = sys.Syscall6(uintptr(s.sysno), syscallArgs[0], syscallArgs[1], syscallArgs[2], syscallArgs[3], syscallArgs[4], syscallArgs[5])
+	default:
+		fmt.Printf("number of sycall arguments not supported: %d\n", numArgs)
+		return subcommands.ExitUsageError
+	}
+	if errno != 0 {
+		fmt.Printf("syscall(%d, %s) failed: %v\n", s.sysno, strings.Join(f.Args(), ", "), errno)
 	} else {
-		fmt.Printf("syscall(%d, 0, 0...) success\n", s.sysno)
+		fmt.Printf("syscall(%d, %s) success\n", s.sysno, strings.Join(f.Args(), ", "))
 	}
 	return subcommands.ExitSuccess
 }
diff --git a/test/util/BUILD b/test/util/BUILD
index 56f94e464..26e779f21 100644
--- a/test/util/BUILD
+++ b/test/util/BUILD
@@ -440,15 +440,15 @@ cc_library(
     defines = select_system(),
     deps = default_net_util() + [
         gtest,
-        "@com_google_absl//absl/memory",
-        "@com_google_absl//absl/strings",
-        "@com_google_absl//absl/strings:str_format",
-        "@com_google_absl//absl/time",
-        "@com_google_absl//absl/types:optional",
         "//test/util:file_descriptor",
         "//test/util:posix_error",
         "//test/util:temp_path",
         "//test/util:test_util",
         "//test/util:thread_util",
+        "@com_google_absl//absl/memory",
+        "@com_google_absl//absl/strings",
+        "@com_google_absl//absl/strings:str_format",
+        "@com_google_absl//absl/time",
+        "@com_google_absl//absl/types:optional",
     ],
 )