From 2052b225d9438328b27acee35a54e3ce1a5ec43e Mon Sep 17 00:00:00 2001
From: Maxime Coste <mawww@kakoune.org>
Date: Sun, 29 Jan 2017 13:56:05 +0000
Subject: [PATCH] Detect too deep command call stack

Fixes #1163
---
 src/command_manager.cc | 9 ++++++++-
 src/command_manager.hh | 3 ++-
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/src/command_manager.cc b/src/command_manager.cc
index 6b79df3c..d8c5bc58 100644
--- a/src/command_manager.cc
+++ b/src/command_manager.cc
@@ -417,11 +417,18 @@ CommandManager::find_command(const Context& context, const String& name) const
 void CommandManager::execute_single_command(CommandParameters params,
                                             Context& context,
                                             const ShellContext& shell_context,
-                                            DisplayCoord pos) const
+                                            DisplayCoord pos)
 {
     if (params.empty())
         return;
 
+    constexpr int max_command_depth = 100;
+    if (m_command_depth > max_command_depth)
+        throw runtime_error("maximum nested command depth hit");
+
+    ++m_command_depth;
+    auto pop_cmd = on_scope_end([this] { --m_command_depth; });
+
     ParameterList param_view(params.begin()+1, params.end());
     auto command_it = find_command(context, params[0]);
     if (command_it == m_commands.end())
diff --git a/src/command_manager.hh b/src/command_manager.hh
index 55d62921..7ef10f2c 100644
--- a/src/command_manager.hh
+++ b/src/command_manager.hh
@@ -112,7 +112,7 @@ private:
     void execute_single_command(CommandParameters params,
                                 Context& context,
                                 const ShellContext& shell_context,
-                                DisplayCoord pos) const;
+                                DisplayCoord pos);
 
     struct CommandDescriptor
     {
@@ -126,6 +126,7 @@ private:
     using CommandMap = UnorderedMap<String, CommandDescriptor, MemoryDomain::Commands>;
     CommandMap m_commands;
     String m_last_complete_command;
+    int m_command_depth = 0;
 
     CommandMap::const_iterator find_command(const Context& context,
                                             const String& name) const;