From e923cf6624b4195479e7881d57d933a0d5275c70 Mon Sep 17 00:00:00 2001
From: Andreas Kling <kling@serenityos.org>
Date: Sat, 25 Dec 2021 11:07:48 +0100
Subject: strace: Port to LibMain :^)

---
 Userland/Utilities/CMakeLists.txt |  1 +
 Userland/Utilities/strace.cpp     | 75 +++++++++++----------------------------
 2 files changed, 22 insertions(+), 54 deletions(-)

(limited to 'Userland')

diff --git a/Userland/Utilities/CMakeLists.txt b/Userland/Utilities/CMakeLists.txt
index af7e417d7f..6c095f1d3b 100644
--- a/Userland/Utilities/CMakeLists.txt
+++ b/Userland/Utilities/CMakeLists.txt
@@ -132,6 +132,7 @@ target_link_libraries(run-tests LibRegex)
 target_link_libraries(shot LibGUI)
 target_link_libraries(sql LibLine LibSQL LibIPC)
 target_link_libraries(stat LibMain)
+target_link_libraries(strace LibMain)
 target_link_libraries(su LibCrypt LibMain)
 target_link_libraries(tar LibArchive LibCompress)
 target_link_libraries(telws LibProtocol LibLine)
diff --git a/Userland/Utilities/strace.cpp b/Userland/Utilities/strace.cpp
index f8e7c9cf8a..4851bd7d07 100644
--- a/Userland/Utilities/strace.cpp
+++ b/Userland/Utilities/strace.cpp
@@ -13,6 +13,7 @@
 #include <LibCore/ArgsParser.h>
 #include <LibCore/File.h>
 #include <LibCore/System.h>
+#include <LibMain/Main.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <netinet/in.h>
@@ -796,12 +797,9 @@ static void format_syscall(FormattedSyscallBuilder& builder, Syscall::Function s
     }
 }
 
-int main(int argc, char** argv)
+ErrorOr<int> serenity_main(Main::Arguments arguments)
 {
-    if (pledge("stdio wpath cpath proc exec ptrace sigaction", nullptr) < 0) {
-        perror("pledge");
-        return 1;
-    }
+    TRY(Core::System::pledge("stdio wpath cpath proc exec ptrace sigaction"));
 
     Vector<const char*> child_argv;
 
@@ -822,16 +820,11 @@ int main(int argc, char** argv)
     parser.add_option(include_syscalls_option, "Comma-delimited syscalls to include", "include", 'i', "include");
     parser.add_positional_argument(child_argv, "Arguments to exec", "argument", Core::ArgsParser::Required::No);
 
-    parser.parse(argc, argv);
+    parser.parse(arguments);
+
+    if (output_filename != nullptr)
+        trace_file = TRY(Core::File::open(output_filename, Core::OpenMode::WriteOnly));
 
-    if (output_filename != nullptr) {
-        auto open_result = Core::File::open(output_filename, Core::OpenMode::WriteOnly);
-        if (open_result.is_error()) {
-            outln(stderr, "Failed to open output file: {}", open_result.error());
-            return 1;
-        }
-        trace_file = open_result.value();
-    }
     auto parse_syscalls = [](const char* option, auto& hash_table) {
         if (option != nullptr) {
             for (auto syscall : StringView(option).split_view(','))
@@ -841,30 +834,19 @@ int main(int argc, char** argv)
     parse_syscalls(exclude_syscalls_option, exclude_syscalls);
     parse_syscalls(include_syscalls_option, include_syscalls);
 
-    if (pledge("stdio proc exec ptrace sigaction", nullptr) < 0) {
-        perror("pledge");
-        return 1;
-    }
+    TRY(Core::System::pledge("stdio proc exec ptrace sigaction"));
 
     int status;
     if (g_pid == -1) {
-        if (child_argv.is_empty()) {
-            warnln("strace: Expected either a pid or some arguments");
-            return 1;
-        }
+        if (child_argv.is_empty())
+            return Error::from_string_literal("Expected either a pid or some arguments"sv);
 
         child_argv.append(nullptr);
-        int pid = fork();
-        if (pid < 0) {
-            perror("fork");
-            return 1;
-        }
+        auto pid = TRY(Core::System::fork());
 
         if (!pid) {
-            if (ptrace(PT_TRACE_ME, 0, 0, 0) == -1) {
-                perror("traceme");
-                return 1;
-            }
+            TRY(Core::System::ptrace(PT_TRACE_ME, 0, 0, 0));
+
             int rc = execvp(child_argv.first(), const_cast<char**>(child_argv.data()));
             if (rc < 0) {
                 perror("execvp");
@@ -880,34 +862,25 @@ int main(int argc, char** argv)
         }
     }
 
-    struct sigaction sa;
-    memset(&sa, 0, sizeof(struct sigaction));
+    struct sigaction sa = {};
     sa.sa_handler = handle_sigint;
-    sigaction(SIGINT, &sa, nullptr);
+    TRY(Core::System::sigaction(SIGINT, &sa, nullptr));
 
-    if (ptrace(PT_ATTACH, g_pid, 0, 0) == -1) {
-        perror("attach");
-        return 1;
-    }
+    TRY(Core::System::ptrace(PT_ATTACH, g_pid, 0, 0));
     if (waitpid(g_pid, &status, WSTOPPED | WEXITED) != g_pid || !WIFSTOPPED(status)) {
         perror("waitpid");
         return 1;
     }
 
     for (;;) {
-        if (ptrace(PT_SYSCALL, g_pid, 0, 0) == -1) {
-            perror("syscall");
-            return 1;
-        }
+        TRY(Core::System::ptrace(PT_SYSCALL, g_pid, 0, 0));
+
         if (waitpid(g_pid, &status, WSTOPPED | WEXITED) != g_pid || !WIFSTOPPED(status)) {
             perror("wait_pid");
             return 1;
         }
         PtraceRegisters regs = {};
-        if (ptrace(PT_GETREGS, g_pid, &regs, 0) == -1) {
-            perror("getregs");
-            return 1;
-        }
+        TRY(Core::System::ptrace(PT_GETREGS, g_pid, &regs, 0));
 #if ARCH(I386)
         syscall_arg_t syscall_index = regs.eax;
         syscall_arg_t arg1 = regs.edx;
@@ -920,19 +893,13 @@ int main(int argc, char** argv)
         syscall_arg_t arg3 = regs.rbx;
 #endif
 
-        if (ptrace(PT_SYSCALL, g_pid, 0, 0) == -1) {
-            perror("syscall");
-            return 1;
-        }
+        TRY(Core::System::ptrace(PT_SYSCALL, g_pid, 0, 0));
         if (waitpid(g_pid, &status, WSTOPPED | WEXITED) != g_pid || !WIFSTOPPED(status)) {
             perror("wait_pid");
             return 1;
         }
 
-        if (ptrace(PT_GETREGS, g_pid, &regs, 0) == -1) {
-            perror("getregs");
-            return 1;
-        }
+        TRY(Core::System::ptrace(PT_GETREGS, g_pid, &regs, 0));
 
 #if ARCH(I386)
         u32 res = regs.eax;
-- 
cgit v1.2.3