Add getppid().

Author: https://github.com/awesomekling
Commit: https://github.com/SerenityOS/serenity/commit/77fe8e83631

Kernel/ProcFileSystem.cpp

@@ -269,7 +269,7 @@ ByteBuffer procfs$summary()
             process->sid(),
             process->uid(),
             toString(process->state()),
-            process->parentPID(),
+            process->ppid(),
             process->timesScheduled(),
             process->number_of_open_file_descriptors(),
             process->tty() ? strrchr(process->tty()->ttyName().characters(), '/') + 1 : "n/a",

Kernel/Process.cpp

@@ -558,7 +558,7 @@ Process* Process::createKernelProcess(void (*e)(), String&& name)
     return process;
 }
 
-Process::Process(String&& name, uid_t uid, gid_t gid, pid_t parentPID, RingLevel ring, RetainPtr<VirtualFileSystem::Node>&& cwd, RetainPtr<VirtualFileSystem::Node>&& executable, TTY* tty, Process* fork_parent)
+Process::Process(String&& name, uid_t uid, gid_t gid, pid_t ppid, RingLevel ring, RetainPtr<VirtualFileSystem::Node>&& cwd, RetainPtr<VirtualFileSystem::Node>&& executable, TTY* tty, Process* fork_parent)
     : m_name(move(name))
     , m_pid(next_pid++) // FIXME: RACE: This variable looks racy!
     , m_uid(uid)
@@ -570,7 +570,7 @@ Process::Process(String&& name, uid_t uid, gid_t gid, pid_t parentPID, RingLevel
     , m_cwd(move(cwd))
     , m_executable(move(executable))
     , m_tty(tty)
-    , m_parentPID(parentPID)
+    , m_ppid(ppid)
 {
     if (fork_parent) {
         m_sid = fork_parent->m_sid;
@@ -578,7 +578,7 @@ Process::Process(String&& name, uid_t uid, gid_t gid, pid_t parentPID, RingLevel
     } else {
         // FIXME: Use a ProcessHandle? Presumably we're executing *IN* the parent right now though..
         InterruptDisabler disabler;
-        if (auto* parent = Process::fromPID(m_parentPID)) {
+        if (auto* parent = Process::fromPID(m_ppid)) {
             m_sid = parent->m_sid;
             m_pgid = parent->m_pgid;
         }
@@ -1315,6 +1315,11 @@ pid_t Process::sys$getpid()
     return m_pid;
 }
 
+pid_t Process::sys$getppid()
+{
+    return m_ppid;
+}
+
 pid_t Process::sys$waitpid(pid_t waitee, int* wstatus, int options)
 {
     if (wstatus)

Kernel/Process.h

@@ -26,7 +26,7 @@ class Process : public InlineLinkedListNode<Process> {
     friend class InlineLinkedListNode<Process>;
 public:
     static Process* createKernelProcess(void (*entry)(), String&& name);
-    static Process* create_user_process(const String& path, uid_t, gid_t, pid_t parentPID, int& error, Vector<String>&& arguments = Vector<String>(), Vector<String>&& environment = Vector<String>(), TTY* = nullptr);
+    static Process* create_user_process(const String& path, uid_t, gid_t, pid_t ppid, int& error, Vector<String>&& arguments = Vector<String>(), Vector<String>&& environment = Vector<String>(), TTY* = nullptr);
     ~Process();
 
     static Vector<Process*> allProcesses();
@@ -67,7 +67,7 @@ public:
     gid_t gid() const { return m_gid; }
     uid_t euid() const { return m_euid; }
     gid_t egid() const { return m_egid; }
-    pid_t parentPID() const { return m_parentPID; }
+    pid_t ppid() const { return m_ppid; }
 
     const FarPtr& farPtr() const { return m_farPtr; }
 
@@ -103,6 +103,7 @@ public:
     uid_t sys$geteuid();
     gid_t sys$getegid();
     pid_t sys$getpid();
+    pid_t sys$getppid();
     int sys$open(const char* path, int options);
     int sys$close(int fd);
     ssize_t sys$read(int fd, void* outbuf, size_t nread);
@@ -179,7 +180,7 @@ private:
     friend class MemoryManager;
     friend bool scheduleNewProcess();
 
-    Process(String&& name, uid_t, gid_t, pid_t parentPID, RingLevel, RetainPtr<VirtualFileSystem::Node>&& cwd = nullptr, RetainPtr<VirtualFileSystem::Node>&& executable = nullptr, TTY* = nullptr, Process* fork_parent = nullptr);
+    Process(String&& name, uid_t, gid_t, pid_t ppid, RingLevel, RetainPtr<VirtualFileSystem::Node>&& cwd = nullptr, RetainPtr<VirtualFileSystem::Node>&& executable = nullptr, TTY* = nullptr, Process* fork_parent = nullptr);
 
     void push_value_on_stack(dword);
 
@@ -233,7 +234,7 @@ private:
 
     LinearAddress m_return_from_signal_trampoline;
 
-    pid_t m_parentPID { 0 };
+    pid_t m_ppid { 0 };
 
     static void notify_waiters(pid_t waitee, int exit_status, int signal);
 

Kernel/Syscall.cpp

@@ -87,6 +87,8 @@ static DWORD handle(RegisterDump& regs, DWORD function, DWORD arg1, DWORD arg2,
         return current->sys$getgid();
     case Syscall::SC_getpid:
         return current->sys$getpid();
+    case Syscall::SC_getppid:
+        return current->sys$getppid();
     case Syscall::SC_waitpid:
         return current->sys$waitpid((pid_t)arg1, (int*)arg2, (int)arg3);
     case Syscall::SC_mmap:

Kernel/Syscall.h

@@ -50,6 +50,7 @@
     __ENUMERATE_SYSCALL(dup) \
     __ENUMERATE_SYSCALL(dup2) \
     __ENUMERATE_SYSCALL(sigaction) \
+    __ENUMERATE_SYSCALL(getppid) \
 
 
 #define DO_SYSCALL_A0(function) Syscall::invoke((dword)(function))

LibC/unistd.cpp

@@ -44,6 +44,11 @@ pid_t getpid()
     return Syscall::invoke(Syscall::SC_getpid);
 }
 
+pid_t getppid()
+{
+    return Syscall::invoke(Syscall::SC_getppid);
+}
+
 pid_t setsid()
 {
     int rc = Syscall::invoke(Syscall::SC_setsid);