Add sys$uname() and a /bin/uname utility.

Kernel/Syscall.cpp

@@ -112,6 +112,8 @@ DWORD handle(DWORD function, DWORD arg1, DWORD arg2, DWORD arg3)
         return current->sys$get_arguments((int*)arg1, (char***)arg2);
     case Syscall::PosixChdir:
         return current->sys$chdir((const char*)arg1);
+    case Syscall::PosixUname:
+        return current->sys$uname((utsname*)arg1);
     default:
         kprintf("int0x80: Unknown function %x requested {%x, %x, %x}\n", function, arg1, arg2, arg3);
         break;

Kernel/Syscall.h

@@ -33,6 +33,7 @@ enum Function {
     PosixGethostname = 0x2001,
     GetArguments = 0x2002,
     PosixChdir = 0x2003,
+    PosixUname = 0x2004,
 };
 
 void initialize();

Kernel/Task.cpp

@@ -26,12 +26,18 @@ static InlineLinkedList<Task>* s_tasks;
 static InlineLinkedList<Task>* s_deadTasks;
 static String* s_hostname;
 
-static String& hostname(InterruptDisabler&)
+static String& hostnameStorage(InterruptDisabler&)
 {
     ASSERT(s_hostname);
     return *s_hostname;
 }
 
+static String getHostname()
+{
+    InterruptDisabler disabler;
+    return hostnameStorage(disabler).isolatedCopy();
+}
+
 static bool contextSwitch(Task*);
 
 static void redoKernelTaskTSS()
@@ -177,14 +183,10 @@ int Task::sys$munmap(void* addr, size_t size)
 
 int Task::sys$gethostname(char* buffer, size_t size)
 {
-    String hn;
-    {
-        InterruptDisabler disabler;
-        hn = hostname(disabler).isolatedCopy();
-    }
-    if (size < (hn.length() + 1))
+    auto hostname = getHostname();
+    if (size < (hostname.length() + 1))
         return -ENAMETOOLONG;
-    memcpy(buffer, hn.characters(), size);
+    memcpy(buffer, hostname.characters(), size);
     return 0;
 }
 
@@ -760,6 +762,16 @@ int Task::sys$open(const char* path, size_t pathLength)
     return fd;
 }
 
+int Task::sys$uname(utsname* buf)
+{
+    strcpy(buf->sysname, "Serenity");
+    strcpy(buf->release, "1.0-dev");
+    strcpy(buf->version, "FIXME");
+    strcpy(buf->machine, "i386");
+    strcpy(buf->nodename, getHostname().characters());
+    return 0;
+}
+
 int Task::sys$kill(pid_t pid, int sig)
 {
     (void) sig;

Kernel/Task.h

@@ -104,6 +104,7 @@ public:
     int sys$gettimeofday(timeval*);
     int sys$gethostname(char* name, size_t length);
     int sys$get_arguments(int* argc, char*** argv);
+    int sys$uname(utsname*);
 
     static void initialize();
 

Kernel/sync-sh

@@ -11,5 +11,6 @@ cp ../Userland/true mnt/bin/true
 cp ../Userland/false mnt/bin/false
 cp ../Userland/hostname mnt/bin/hostname
 cp ../Userland/cat mnt/bin/cat
+cp ../Userland/uname mnt/bin/uname
 umount mnt
 sync

Kernel/types.h

@@ -31,6 +31,16 @@ struct timeval {
     suseconds_t tv_usec;
 };
 
+#define UTSNAME_ENTRY_LEN 65
+
+struct utsname {
+    char sysname[UTSNAME_ENTRY_LEN];
+    char nodename[UTSNAME_ENTRY_LEN];
+    char release[UTSNAME_ENTRY_LEN];
+    char version[UTSNAME_ENTRY_LEN];
+    char machine[UTSNAME_ENTRY_LEN];
+};
+
 struct FarPtr {
     DWORD offset { 0 };
     WORD selector { 0 };