From b2e4fe1299bd57b4ab4bb7ea0e0133038db52b26 Mon Sep 17 00:00:00 2001
From: Linus Groh <mail@linusgroh.de>
Date: Sun, 25 Oct 2020 23:25:41 +0000
Subject: [PATCH] Shell+LibLine: Move Shell::{load,save}_history() to
 Line::Editor

This allows us to easily re-use history loading and saving in other
programs using Line::Editor, as well as implementing universally
recognized HISTCONTROL.
---
 Libraries/LibLine/Editor.cpp | 27 +++++++++++++++++++++++++++
 Libraries/LibLine/Editor.h   |  4 +++-
 Shell/Builtin.cpp            |  2 +-
 Shell/Shell.cpp              | 28 ++--------------------------
 Shell/Shell.h                |  4 ++--
 Shell/main.cpp               |  2 +-
 6 files changed, 36 insertions(+), 31 deletions(-)

diff --git a/Libraries/LibLine/Editor.cpp b/Libraries/LibLine/Editor.cpp
index 28f66ce7181..c103d5ccf9e 100644
--- a/Libraries/LibLine/Editor.cpp
+++ b/Libraries/LibLine/Editor.cpp
@@ -34,6 +34,7 @@
 #include <LibCore/ConfigFile.h>
 #include <LibCore/Event.h>
 #include <LibCore/EventLoop.h>
+#include <LibCore/File.h>
 #include <LibCore/Notifier.h>
 #include <ctype.h>
 #include <signal.h>
@@ -212,6 +213,32 @@ void Editor::add_to_history(const String& line)
     m_history.append(line);
 }
 
+bool Editor::load_history(const String& path)
+{
+    auto history_file = Core::File::construct(path);
+    if (!history_file->open(Core::IODevice::ReadOnly))
+        return false;
+    while (history_file->can_read_line()) {
+        auto b = history_file->read_line(1024);
+        // skip the newline and terminating bytes
+        add_to_history(String(reinterpret_cast<const char*>(b.data()), b.size() - 2));
+    }
+    return true;
+}
+
+bool Editor::save_history(const String& path)
+{
+    auto file_or_error = Core::File::open(path, Core::IODevice::WriteOnly, 0600);
+    if (file_or_error.is_error())
+        return false;
+    auto& file = *file_or_error.value();
+    for (const auto& line : m_history) {
+        file.write(line);
+        file.write("\n");
+    }
+    return true;
+}
+
 void Editor::clear_line()
 {
     for (size_t i = 0; i < m_cursor; ++i)
diff --git a/Libraries/LibLine/Editor.h b/Libraries/LibLine/Editor.h
index 076acdc8306..f2513fbe6c3 100644
--- a/Libraries/LibLine/Editor.h
+++ b/Libraries/LibLine/Editor.h
@@ -143,7 +143,9 @@ public:
 
     void initialize();
 
-    void add_to_history(const String&);
+    void add_to_history(const String& line);
+    bool load_history(const String& path);
+    bool save_history(const String& path);
     const Vector<String>& history() const { return m_history; }
 
     void register_key_input_callback(const KeyBinding&);
diff --git a/Shell/Builtin.cpp b/Shell/Builtin.cpp
index ee71a4e6db5..c719abef32a 100644
--- a/Shell/Builtin.cpp
+++ b/Shell/Builtin.cpp
@@ -267,7 +267,7 @@ int Shell::builtin_exit(int argc, const char** argv)
         }
     }
     stop_all_jobs();
-    save_history();
+    m_editor->save_history(get_history_path());
     if (m_is_interactive)
         printf("Good-bye!\n");
     exit(exit_code);
diff --git a/Shell/Shell.cpp b/Shell/Shell.cpp
index 36899a30f42..05fe1f66a69 100644
--- a/Shell/Shell.cpp
+++ b/Shell/Shell.cpp
@@ -966,30 +966,6 @@ String Shell::get_history_path()
     return builder.to_string();
 }
 
-void Shell::load_history()
-{
-    auto history_file = Core::File::construct(get_history_path());
-    if (!history_file->open(Core::IODevice::ReadOnly))
-        return;
-    while (history_file->can_read_line()) {
-        auto b = history_file->read_line(1024);
-        // skip the newline and terminating bytes
-        m_editor->add_to_history(String(reinterpret_cast<const char*>(b.data()), b.size() - 2));
-    }
-}
-
-void Shell::save_history()
-{
-    auto file_or_error = Core::File::open(get_history_path(), Core::IODevice::WriteOnly, 0600);
-    if (file_or_error.is_error())
-        return;
-    auto& file = *file_or_error.value();
-    for (const auto& line : m_editor->history()) {
-        file.write(line);
-        file.write("\n");
-    }
-}
-
 String Shell::escape_token(const String& token)
 {
     StringBuilder builder;
@@ -1559,7 +1535,7 @@ Shell::Shell(Line::Editor& editor)
     }
 
     directory_stack.append(cwd);
-    load_history();
+    m_editor->load_history(get_history_path());
     cache_path();
 }
 
@@ -1569,7 +1545,7 @@ Shell::~Shell()
         return;
 
     stop_all_jobs();
-    save_history();
+    m_editor->save_history(get_history_path());
 }
 
 void Shell::stop_all_jobs()
diff --git a/Shell/Shell.h b/Shell/Shell.h
index 4f61942fe8b..d485979c73f 100644
--- a/Shell/Shell.h
+++ b/Shell/Shell.h
@@ -109,6 +109,8 @@ public:
 
     String format(const StringView&, ssize_t& cursor) const;
 
+    RefPtr<Line::Editor> editor() const { return m_editor; }
+
     struct LocalFrame {
         HashMap<String, RefPtr<AST::Value>> local_variables;
     };
@@ -154,8 +156,6 @@ public:
     void kill_job(const Job*, int sig);
 
     String get_history_path();
-    void load_history();
-    void save_history();
     void print_path(const String& path);
 
     bool read_single_line();
diff --git a/Shell/main.cpp b/Shell/main.cpp
index 4ab4805a5b6..cc2c08d308c 100644
--- a/Shell/main.cpp
+++ b/Shell/main.cpp
@@ -57,7 +57,7 @@ int main(int argc, char** argv)
         for (auto& it : s_shell->jobs)
             s_shell->kill_job(it.value.ptr(), SIGHUP);
 
-        s_shell->save_history();
+        s_shell->editor()->save_history(s_shell->get_history_path());
     });
 
     editor = Line::Editor::construct();