kernel+terminal: Move pseudoterminal input processing to kernel-space

kernel/src/fs/devices/MasterPTY.cpp

@@ -5,6 +5,7 @@
 #include "fs/devpts/FileSystem.h"
 #include "memory/MemoryManager.h"
 #include "thread/Scheduler.h"
+#include <luna/CType.h>
 
 Result<SharedPtr<VFS::Inode>> MasterPTY::create_pair(int index)
 {
@@ -57,6 +58,130 @@ Result<void> MasterPTY::handle_background_process_group(bool can_succeed, int si
     return err(EIO);
 }
 
+bool MasterPTY::is_canonical()
+{
+    return m_settings.c_lflag & ICANON;
+}
+
+Result<void> MasterPTY::handle_input(u8 key)
+{
+    bool is_special_character { false };
+
+    if (is_canonical())
+    {
+        if (key == m_settings.c_cc[VERASE])
+        {
+            auto maybe_char = m_current_line_buffer.try_pop();
+            if (maybe_char.has_value() && maybe_char.value())
+            {
+                if ((m_settings.c_lflag & ECHO) && (m_settings.c_lflag & ECHOE))
+                {
+                    u8 backspace = (u8)'\b';
+                    m_buffer.append_data(&backspace, 1);
+                    if (_iscntrl(maybe_char.value())) m_buffer.append_data(&backspace, 1);
+                    if (maybe_char.value() == '\t')
+                    {
+                        m_buffer.append_data(&backspace, 1);
+                        m_buffer.append_data(&backspace, 1);
+                    }
+                    return {};
+                }
+                return {};
+            }
+
+            if ((m_settings.c_lflag & ECHOE)) return {};
+            else
+                is_special_character = true;
+        }
+
+        if (key == m_settings.c_cc[VEOF])
+        {
+            const auto size = m_current_line_buffer.size();
+            auto buffer = Buffer { m_current_line_buffer.release_data(), size };
+            TRY(m_lines.try_append(move(buffer)));
+
+            is_special_character = true;
+        }
+
+        if (m_settings.c_lflag & ISIG)
+        {
+            if (key == m_settings.c_cc[VINTR])
+            {
+                if (!(m_settings.c_lflag & NOFLSH)) m_current_line_buffer.clear();
+
+                if (m_foreground_process_group.has_value())
+                    Scheduler::for_each_in_process_group(*m_foreground_process_group, [](Thread* thread) {
+                        thread->send_signal(SIGINT);
+                        return true;
+                    });
+
+                is_special_character = true;
+            }
+
+            if (key == m_settings.c_cc[VQUIT])
+            {
+                if (!(m_settings.c_lflag & NOFLSH)) m_current_line_buffer.clear();
+
+                if (m_foreground_process_group.has_value())
+                    Scheduler::for_each_in_process_group(*m_foreground_process_group, [](Thread* thread) {
+                        thread->send_signal(SIGQUIT);
+                        return true;
+                    });
+
+                is_special_character = true;
+            }
+        }
+    }
+
+    if (!is_special_character)
+    {
+        if (is_canonical())
+        {
+            const usize max_line_size = key == '\n' ? 4096 : 4095;
+            if (m_current_line_buffer.size() < max_line_size) TRY(m_current_line_buffer.try_append(key));
+
+            if (key == '\n')
+            {
+                const auto size = m_current_line_buffer.size();
+                auto buffer = Buffer { m_current_line_buffer.release_data(), size };
+                TRY(m_lines.try_append(move(buffer)));
+            }
+        }
+        else
+            TRY(m_slave->m_buffer.append_data(&key, 1));
+    }
+
+    if (!(m_settings.c_lflag & ECHO)) return {};
+
+    if (_iscntrl(key))
+    {
+        if (m_settings.c_lflag & ECHOCTL)
+        {
+            bool should_echo = true;
+            if (key == '\n' || key == '\t' || key == '\0' || key == m_settings.c_cc[VEOF]) should_echo = false;
+
+            if (should_echo)
+            {
+                u8 caret_notation[2] = {
+                    '^',
+                    '\0',
+                };
+                if (key == 0x7f) caret_notation[1] = '?';
+                else
+                    caret_notation[1] = key + 0x40;
+
+                m_buffer.append_data(caret_notation, 2);
+            }
+            else
+                m_buffer.append_data(&key, 1);
+        }
+    }
+    else
+        m_buffer.append_data(&key, 1);
+
+    return {};
+}
+
 Result<usize> MasterPTY::read(u8* buf, usize, usize length) const
 {
     length = m_buffer.dequeue_data(buf, length);
@@ -66,7 +191,7 @@ Result<usize> MasterPTY::read(u8* buf, usize, usize length) const
 
 Result<usize> MasterPTY::write(const u8* buf, usize, usize length)
 {
-    TRY(m_slave->m_buffer.append_data(buf, length));
+    for (usize i = 0; i < length; i++) { TRY(handle_input(buf[i])); }
 
     return length;
 }

kernel/src/fs/devices/MasterPTY.h

@@ -67,7 +67,15 @@ class MasterPTY : public VFS::DeviceInode
     mutable Option<pid_t> m_foreground_process_group;
     struct winsize m_window;
 
+    typedef Vector<u8> Line;
+
+    Vector<Buffer> m_lines;
+    Line m_current_line_buffer;
+
     Result<void> handle_background_process_group(bool can_succeed, int signo) const;
+    Result<void> handle_input(u8 key);
+
+    bool is_canonical();
 
     int m_index;
 

kernel/src/fs/devices/SlavePTY.cpp

@@ -10,7 +10,15 @@ Result<usize> SlavePTY::read(u8* buf, usize, usize length) const
 
     TRY(m_master->handle_background_process_group(false, SIGTTIN));
 
-    length = m_buffer.dequeue_data(buf, length);
+    if (!m_master->is_canonical()) length = m_buffer.dequeue_data(buf, length);
+    else
+    {
+        if (m_master->m_lines.size() == 0) { return 0; }
+
+        auto& line = m_master->m_lines[0];
+        length = line.dequeue_data(buf, length);
+        if (line.size() == 0) m_master->m_lines.remove_at(0);
+    }
 
     return length;
 }
@@ -26,6 +34,13 @@ Result<usize> SlavePTY::write(const u8* buf, usize, usize length)
     return length;
 }
 
+bool SlavePTY::will_block_if_read() const
+{
+    if (!m_master->is_canonical()) return m_buffer.is_empty();
+    else
+        return !m_master->m_lines.size();
+}
+
 Result<u64> SlavePTY::ioctl(int request, void* arg)
 {
     auto* current = Scheduler::current();

kernel/src/fs/devices/SlavePTY.h

@@ -42,10 +42,7 @@ class SlavePTY : public VFS::DeviceInode
         return err(EINVAL);
     }
 
-    bool will_block_if_read() const override
-    {
-        return m_buffer.is_empty();
-    }
+    bool will_block_if_read() const override;
 
     void did_link() override
     {

libluna/include/luna/Buffer.h

@@ -20,6 +20,16 @@ class Buffer
     Buffer();
     ~Buffer();
 
+    /**
+     * @brief Create a new Buffer object, adopting existing data.
+     *
+     * The data provided will be owned by the buffer.
+     *
+     * @param data The data to use.
+     * @param size The amount of bytes in the data.
+     */
+    Buffer(u8* data, usize size);
+
     Buffer(Buffer&& other);
     Buffer(const Buffer& other) = delete; // For now.
 
@@ -161,8 +171,6 @@ class Buffer
     }
 
   private:
-    Buffer(u8* data, usize size);
-
     u8* m_data { nullptr };
     usize m_size { 0 };
 };

terminal/TerminalWidget.cpp

@@ -95,115 +95,7 @@ Result<ui::EventResult> TerminalWidget::handle_key_event(const ui::KeyEventReque
     // invalid zero byte into the terminal input (this would also happen on Shift or Ctrl keypresses).
     if (request.letter == '\0') return ui::EventResult::DidNotHandle;
 
-    return handle_input(request.letter);
-}
-
-Result<ui::EventResult> TerminalWidget::handle_input(char key)
-{
-    query_termios();
-
-    bool is_special_character { false };
-
-    if (is_canonical())
-    {
-        if (key == m_settings.c_cc[VERASE])
-        {
-            auto maybe_char = m_line_buffer.try_pop();
-            if (maybe_char.has_value() && maybe_char.value())
-            {
-                if ((m_settings.c_lflag & ECHO) && (m_settings.c_lflag & ECHOE))
-                {
-                    put_code_point(L'\b');
-                    if (_iscntrl(maybe_char.value())) put_code_point(L'\b');
-                    if (maybe_char.value() == '\t')
-                    {
-                        put_code_point(L'\b');
-                        put_code_point(L'\b');
-                    }
-                    return ui::EventResult::DidHandle;
-                }
-                return ui::EventResult::DidNotHandle;
-            }
-
-            if ((m_settings.c_lflag & ECHOE)) return ui::EventResult::DidNotHandle;
-            else
-                is_special_character = true;
-        }
-
-        if (key == m_settings.c_cc[VEOF])
-        {
-            write(m_pty, m_line_buffer.data(), m_line_buffer.size());
-            m_line_buffer.clear();
-
-            // FIXME: tell the kernel that process may read without blocking.
-            is_special_character = true;
-        }
-
-        if (m_settings.c_lflag & ISIG)
-        {
-            if (key == m_settings.c_cc[VINTR])
-            {
-                if (!(m_settings.c_lflag & NOFLSH)) m_line_buffer.clear();
-
-                pid_t group = tcgetpgrp(m_pty);
-                TRY(os::Process::kill(-group, SIGINT));
-
-                is_special_character = true;
-            }
-
-            if (key == m_settings.c_cc[VQUIT])
-            {
-                if (!(m_settings.c_lflag & NOFLSH)) m_line_buffer.clear();
-
-                pid_t group = tcgetpgrp(m_pty);
-                TRY(os::Process::kill(-group, SIGQUIT));
-
-                is_special_character = true;
-            }
-        }
-    }
-
-    if (!is_special_character)
-    {
-        if (is_canonical())
-        {
-            m_line_buffer.try_append((u8)key);
-
-            if (key == '\n')
-            {
-                write(m_pty, m_line_buffer.data(), m_line_buffer.size());
-                m_line_buffer.clear();
-            }
-        }
-        else
-            write(m_pty, &key, 1);
-    }
-
-    if (!(m_settings.c_lflag & ECHO)) return ui::EventResult::DidNotHandle;
-
-    if (_iscntrl(key))
-    {
-        if (m_settings.c_lflag & ECHOCTL)
-        {
-            bool should_echo = true;
-            if (key == '\n' || key == '\t' || key == '\0' || key == m_settings.c_cc[VEOF]) should_echo = false;
-
-            if (should_echo)
-            {
-                char caret_notation[3] = { '^', '\0', '\0' };
-                if (key == 0x7f) caret_notation[1] = '?';
-                else
-                    caret_notation[1] = key + 0x40;
-
-                for (int i = 0; i < 2; i++) { putchar(caret_notation[i]); }
-            }
-            else
-                putchar(key);
-        }
-    }
-    else
-        putchar(key);
-
+    write(m_pty, &request.letter, 1);
     return ui::EventResult::DidHandle;
 }
 
@@ -223,8 +115,6 @@ Result<bool> TerminalWidget::process()
             return err(errno);
     }
 
-    query_termios();
-
     bool should_update_cursor = tick_cursor();
 
     ssize_t drawn = 0;
@@ -263,16 +153,6 @@ bool TerminalWidget::tick_cursor()
     return false;
 }
 
-void TerminalWidget::query_termios()
-{
-    tcgetattr(m_pty, &m_settings);
-}
-
-bool TerminalWidget::is_canonical()
-{
-    return m_settings.c_lflag & ICANON;
-}
-
 void TerminalWidget::draw_glyph(wchar_t c, int x, int y)
 {
     auto subcanvas = m_terminal_canvas.subcanvas({ x, y, m_font->width(), m_font->height() });

terminal/TerminalWidget.h

@@ -47,16 +47,11 @@ class TerminalWidget : public ui::Widget
     ui::Color m_foreground_color { ui::WHITE };
     ui::Color m_background_color { ui::BLACK };
 
-    void query_termios();
-
     bool tick_cursor();
 
     Utf8StateDecoder m_decoder;
     Option<EscapeSequenceParser> m_escape_parser;
 
-    Result<ui::EventResult> handle_input(char key);
-
-    bool is_canonical();
     void draw_glyph(wchar_t c, int x, int y);
     void erase_current_line();
     void scroll();