HackStudio: Show the slave pty's PGID in the ProcessStateWidget

This is the closest I could figure out how to get to what's actively
running on the terminal view at the moment.

Perhaps we can bundle up every process with the same tty and sum it
all up somehow. I'm not sure.

DevTools/HackStudio/ProcessStateWidget.cpp

@@ -3,6 +3,7 @@
 #include <LibCore/CTimer.h>
 #include <LibGUI/GBoxLayout.h>
 #include <LibGUI/GLabel.h>
+#include <unistd.h>
 
 ProcessStateWidget::ProcessStateWidget(GWidget* parent)
     : GWidget(parent)
@@ -40,7 +41,7 @@ ProcessStateWidget::~ProcessStateWidget()
 
 void ProcessStateWidget::refresh()
 {
-    if (m_pid == -1) {
+    if (m_tty_fd == -1) {
         m_pid_label->set_text("(none)");
         m_state_label->set_text("n/a");
         m_cpu_label->set_text("n/a");
@@ -48,8 +49,10 @@ void ProcessStateWidget::refresh()
         return;
     }
 
+    pid_t pid = tcgetpgrp(m_tty_fd);
+
     auto processes = CProcessStatisticsReader::get_all();
-    auto child_process_data = processes.get(m_pid);
+    auto child_process_data = processes.get(pid);
 
     if (!child_process_data.has_value())
         return;
@@ -58,14 +61,14 @@ void ProcessStateWidget::refresh()
 
     auto& data = active_process_data.value();
 
-    m_pid_label->set_text(String::format("%s(%d)", data.name.characters(), m_pid));
+    m_pid_label->set_text(String::format("%s(%d)", data.name.characters(), pid));
     m_state_label->set_text(data.state);
     m_cpu_label->set_text(String::format("%d", data.times_scheduled));
     m_memory_label->set_text(String::format("%d", data.amount_resident));
 }
 
-void ProcessStateWidget::set_pid(pid_t pid)
+void ProcessStateWidget::set_tty_fd(int tty_fd)
 {
-    m_pid = pid;
+    m_tty_fd = tty_fd;
     refresh();
 }

DevTools/HackStudio/ProcessStateWidget.h

@@ -10,7 +10,7 @@ class ProcessStateWidget final : public GWidget {
 public:
     virtual ~ProcessStateWidget() override;
 
-    void set_pid(pid_t);
+    void set_tty_fd(int);
 
 private:
     explicit ProcessStateWidget(GWidget* parent);
@@ -24,5 +24,5 @@ private:
 
     RefPtr<CTimer> m_timer;
 
-    pid_t m_pid { -1 };
+    int m_tty_fd { -1 };
 };

DevTools/HackStudio/TerminalWrapper.cpp

@@ -45,7 +45,7 @@ void TerminalWrapper::run_command(const String& command)
         } else if (WIFSIGNALED(wstatus)) {
             m_terminal_widget->inject_string(String::format("\033[34;1m(Command signaled with %s!)\033[0m\n", strsignal(WTERMSIG(wstatus))));
         }
-        m_process_state_widget->set_pid(-1);
+        m_process_state_widget->set_tty_fd(-1);
         m_pid = -1;
     };
 
@@ -110,7 +110,7 @@ void TerminalWrapper::run_command(const String& command)
     }
 
     // Parent process, cont'd.
-    m_process_state_widget->set_pid(m_pid);
+    m_process_state_widget->set_tty_fd(ptm_fd);
 }
 
 TerminalWrapper::TerminalWrapper(GWidget* parent)