external_bridge.cpp File Reference

Unix socket MCP bridge implementation. More...

#include <entropic/mcp/external_bridge.h>
#include <entropic/entropic.h>
#include <entropic/types/logging.h>
#include "engine_handle.h"
#include "final_text.h"
#include "tool_namespace.h"
#include <nlohmann/json.hpp>
#include <atomic>
#include <cerrno>
#include <algorithm>
#include <chrono>
#include <condition_variable>
#include <cstring>
#include <filesystem>
#include <fstream>
#include <functional>
#include <mutex>
#include <sstream>
#include <thread>
#include <unordered_map>
#include <unordered_set>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/un.h>
#include <poll.h>

Include dependency graph for external_bridge.cpp:

Go to the source code of this file.

Classes
struct	entropic::AsyncFinalState
	Handle entropic.context_clear. More...

Namespaces
namespace	entropic
	Activate model on GPU (WARM → ACTIVE).
namespace	entropic::tool_suffix
	The bare tool suffixes this bridge exposes, in advertised order.

Typedefs
using	json = nlohmann::json
using	entropic::ToolHandler = json(*)(entropic_handle_t, ExternalBridge *, const json &)
	A non-ask tool's handler (v2.14.3).

Functions
std::filesystem::path	entropic::compute_socket_path (const std::filesystem::path &project_dir)
	Compute project-unique Unix socket path for self-detection.
static std::string	entropic::rpc_ok (const json &id, const json &result)
	Build a JSON-RPC success response.
static std::string	entropic::rpc_err (const json &id, int code, const std::string &msg)
	Build a JSON-RPC error response.
static json	entropic::tool_text (const std::string &text)
	Wrap text in MCP tool result shape.
static std::string	entropic::describe (const ExternalMCPConfig &cfg, const char *suffix, const char *fallback)
	Resolve a tool's description, honouring any consumer override.
static json	entropic::no_args_tool (const ExternalMCPConfig &cfg, const char *suffix, const char *fallback)
	Definition for a tool that takes no arguments.
static json	entropic::session_scoped_tool (const ExternalMCPConfig &cfg, const char *suffix, const char *fallback)
	Definition for a tool scoped to an optional session (gh#144).
static json	entropic::ask_tool (const ExternalMCPConfig &cfg)
	Definition for the ask tool (prompt + optional async).
static json	entropic::ask_status_tool (const ExternalMCPConfig &cfg)
	Definition for the ask_status tool (task_id lookup).
static json	entropic::tool_definitions (const ExternalMCPConfig &cfg)
	MCP tool definitions exposed by the bridge.
static void	entropic::write_json_line (int fd, const json &msg)
	Write a JSON-RPC line to a socket fd.
static void	entropic::send_progress (int fd, const std::string &token_text, const json &progress_token, uint64_t seq)
	Send an MCP progress notification with a text token.
static json	entropic::final_answer_from_context (entropic_handle_t handle, const std::string &session_key)
	Read the live conversation and render the operator-visible answer.
static entropic_error_t	entropic::run_plain_turn (entropic_handle_t handle, const std::string &session_key, const std::string &tier, const std::string &prompt, char **result_json)
	Run one non-streaming turn, under tier when one is given (gh#205).
static entropic_error_t	entropic::run_stream_turn (entropic_handle_t handle, const std::string &session_key, const std::string &tier, const std::string &prompt, void(*on_token)(const char *, size_t, void *), void *ud)
	Run one streaming turn, under tier when one is given (gh#205).
static json	entropic::handle_ask_plain (entropic_handle_t handle, const json &args, const std::string &session_key)
	Handle entropic.ask — non-streaming path (gh#115, v2.9.12).
static json	entropic::handle_ask (entropic_handle_t handle, const json &args, const std::string &session_key, int client_fd, const json &progress_token)
	Handle entropic.ask — stream tokens then return final text.
static json	entropic::handle_status (entropic_handle_t handle, const ExternalBridge *bridge)
	Handle the status tool.
static AsyncFinalState	entropic::derive_async_final_state (entropic_handle_t handle, entropic_error_t err, char *result_json)
	Translate entropic_run's return code into a final task state.
static bool	entropic::mark_tasks_cancelling (ExternalBridge *bridge, const std::string &session_key)
	Mark one session's queued/running tasks as cancelling.
static bool	entropic::any_cancelling_left (ExternalBridge *bridge, const std::string &session_key)
	True while one session's task is still phase=cancelling.
static void	entropic::cancel_inflight_async_tasks (entropic_handle_t handle, ExternalBridge *bridge, const std::string &session_key)
	Cancel any async tasks currently running on the bridge.
static json	entropic::handle_clear (entropic_handle_t handle, ExternalBridge *bridge, const std::string &session_key)
	entropic.context_clear MCP tool handler.
static json	entropic::handle_count (entropic_handle_t handle, const std::string &session_key)
	Handle entropic.context_count.
static std::string	entropic::generate_task_id ()
	Generate a simple UUID-like task ID.
static std::string	entropic::bound_workspace (entropic_handle_t handle, const std::string &session_key)
	The session's current workspace binding, or "" (gh#205).
static std::string	entropic::resolve_workspace (entropic_handle_t handle, const std::string &workspace, std::string &err)
	Resolve workspace to a workspace name, creating one for a path.
static std::string	entropic::bind_session_workspace (entropic_handle_t handle, const std::string &session_key, const std::string &workspace)
	Bind a session to the requested workspace, idempotently (gh#205).
static json	entropic::ask_in_turn (entropic_handle_t handle, ExternalBridge *bridge, const json &args, const std::string &session_key, int client_fd, const json &progress_token)
	Run a sync ask once this session's turn comes up (gh#144, gh#205).
static json	entropic::dispatch_ask (entropic_handle_t handle, ExternalBridge *bridge, const json &args, int client_fd, const json &progress_token)
	Route entropic.ask — sync (streaming) or async.
static std::string	entropic::resident_tiers (entropic_handle_t handle)
	Names of the models resident right now, from the snapshot.
static json	entropic::handle_release (entropic_handle_t handle)
	release: unload every resident model, keep everything else.
static const std::unordered_map< std::string, ToolHandler > &	entropic::tool_handlers ()
	Non-ask tools by suffix (v2.14.3).
static json	entropic::dispatch_tool (entropic_handle_t handle, ExternalBridge *bridge, const json &params, int client_fd, const std::string &call_id)
	Dispatch a tools/call to the appropriate handler.
static void	entropic::prepare_socket_dir (const std::filesystem::path &parent)
	Prepare the socket containing directory with 0700 perms.
static bool	entropic::socket_path_safe (const std::filesystem::path &path)
	Reject a pre-existing path that is a symlink or non-socket.
static bool	entropic::bind_and_listen (int fd, const std::filesystem::path &path)
	Bind+listen on an AF_UNIX socket, applying 0600 perms.
static int	entropic::create_listen_socket (const std::filesystem::path &path)
	Create, bind, and listen on a unix domain socket.
static bool	entropic::peer_uid_matches (int client_fd)
	Validate that the connecting peer shares the engine's UID.
static std::string	entropic::read_line (int fd)
	Read one newline-delimited line from a socket fd.
static json	entropic::initialize_result (const ExternalMCPConfig &cfg)
	Build the MCP initialize response payload.
static void	entropic::phase_observer_cb (int state, void *ud)
	State observer that projects VERIFYING onto task phase.
static json	entropic::task_complete_notification (const std::string &task_id, const std::string &status)
	The completion notification for an async task (Issue #4, v2.1.2).
static bool	entropic::send_nonblocking (int fd, const std::string &payload)
	One non-blocking write of a whole payload to one fd.
static const char *	entropic::sentinel_suffix_for_status (const std::string &status)
	Map a terminal status string to a sentinel filename suffix.

Variables
static auto	entropic::logger = entropic::log::get("mcp.external_bridge")
static std::mutex	entropic::s_bound_sockets_mu
static std::unordered_set< std::string >	entropic::s_bound_sockets
constexpr const char *	entropic::tool_suffix::kAsk = "ask"
constexpr const char *	entropic::tool_suffix::kAskStatus = "ask_status"
constexpr const char *	entropic::tool_suffix::kStatus = "status"
constexpr const char *	entropic::tool_suffix::kContextClear = "context_clear"
constexpr const char *	entropic::tool_suffix::kContextCount = "context_count"
constexpr const char *	entropic::tool_suffix::kRelease = "release"

Detailed Description

Unix socket MCP bridge implementation.

Listens on a unix domain socket, serves every connected client on its own thread, and dispatches JSON-RPC 2.0 (MCP) to the engine handle. Turns queue per session (v2.14.0); a session's async completions, clears and cancels touch only that session and that client.

Version

2.14.0

Definition in file external_bridge.cpp.

Typedef Documentation

json

using json = nlohmann::json

Definition at line 44 of file external_bridge.cpp.