apps: Add uname

apps/CMakeLists.txt

@@ -24,3 +24,4 @@ luna_app(chmod.cpp chmod OFF)
 luna_app(mkdir.cpp mkdir OFF)
 luna_app(rm.cpp rm OFF)
 luna_app(stat.cpp stat OFF)
+luna_app(uname.cpp uname OFF)

apps/uname.cpp

@@ -0,0 +1,59 @@
+#include <os/ArgumentParser.h>
+#include <stdio.h>
+#include <sys/utsname.h>
+
+#define OPERATING_SYSTEM "Luna"
+
+void print_sequenced(const char* string)
+{
+    static bool first { true };
+    if (!first) { putchar(' '); }
+    first = false;
+    fputs(string, stdout);
+}
+
+Result<int> luna_main(int argc, char** argv)
+{
+    bool all { false };
+    bool kernel_name { false };
+    bool node_name { false };
+    bool kernel_release { false };
+    bool kernel_version { false };
+    bool machine { false };
+    bool operating_system { false };
+
+    os::ArgumentParser parser;
+    parser.add_description("Print system information. If given no options, defaults to -s."_sv);
+    parser.add_switch_argument(all, 'a', "all"_sv, "print all information"_sv);
+    parser.add_switch_argument(kernel_name, 's', "kernel-name"_sv, "print the kernel name"_sv);
+    parser.add_switch_argument(node_name, 'n', "nodename"_sv, "print the network hostname"_sv);
+    parser.add_switch_argument(kernel_release, 'r', "kernel-release"_sv, "print the kernel release"_sv);
+    parser.add_switch_argument(kernel_version, 'v', "kernel-version"_sv, "print the kernel version"_sv);
+    parser.add_switch_argument(machine, 'm', "machine"_sv, "print the machine name"_sv);
+    parser.add_switch_argument(operating_system, 'o', "operating-system"_sv, "print the operating system"_sv);
+    parser.parse(argc, argv);
+
+    // If no options are given, default is -s.
+    if (!all && !kernel_name && !node_name && !kernel_release && !kernel_version && !machine && !operating_system)
+        kernel_name = true;
+
+    if (all) kernel_name = node_name = kernel_release = kernel_version = machine = operating_system = true;
+
+    struct utsname info;
+    if (uname(&info) < 0)
+    {
+        perror("uname");
+        return 1;
+    }
+
+    if (kernel_name) print_sequenced(info.sysname);
+    if (node_name) print_sequenced(info.nodename);
+    if (kernel_release) print_sequenced(info.release);
+    if (kernel_version) print_sequenced(info.version);
+    if (machine) print_sequenced(info.machine);
+    if (operating_system) print_sequenced(OPERATING_SYSTEM);
+
+    putchar('\n');
+
+    return 0;
+}

libc/CMakeLists.txt

@@ -22,6 +22,7 @@ set(SOURCES
     src/sys/mman.cpp
     src/sys/wait.cpp
     src/sys/ioctl.cpp
+    src/sys/utsname.cpp
 )
 
 if(${LUNA_ARCH} STREQUAL "x86_64")

libc/src/sys/utsname.cpp

@@ -0,0 +1,13 @@
+#include <bits/errno-return.h>
+#include <sys/syscall.h>
+#include <sys/utsname.h>
+#include <unistd.h>
+
+extern "C"
+{
+    int uname(struct utsname* buf)
+    {
+        long rc = syscall(SYS_uname, buf);
+        __errno_return(rc, int);
+    }
+}