From bae9f6d2fd5eb5bc80929bd393932b23f14d7c93 Mon Sep 17 00:00:00 2001 From: Jake Champlin Date: Tue, 6 Jun 2017 12:40:07 -0400 Subject: Initial transfer of provider code --- vendor/github.com/hashicorp/go-plugin/server.go | 222 ++++++++++++++++++++++++ 1 file changed, 222 insertions(+) create mode 100644 vendor/github.com/hashicorp/go-plugin/server.go (limited to 'vendor/github.com/hashicorp/go-plugin/server.go') diff --git a/vendor/github.com/hashicorp/go-plugin/server.go b/vendor/github.com/hashicorp/go-plugin/server.go new file mode 100644 index 0000000..b5c5270 --- /dev/null +++ b/vendor/github.com/hashicorp/go-plugin/server.go @@ -0,0 +1,222 @@ +package plugin + +import ( + "errors" + "fmt" + "io/ioutil" + "log" + "net" + "os" + "os/signal" + "runtime" + "strconv" + "sync/atomic" +) + +// CoreProtocolVersion is the ProtocolVersion of the plugin system itself. +// We will increment this whenever we change any protocol behavior. This +// will invalidate any prior plugins but will at least allow us to iterate +// on the core in a safe way. We will do our best to do this very +// infrequently. +const CoreProtocolVersion = 1 + +// HandshakeConfig is the configuration used by client and servers to +// handshake before starting a plugin connection. This is embedded by +// both ServeConfig and ClientConfig. +// +// In practice, the plugin host creates a HandshakeConfig that is exported +// and plugins then can easily consume it. +type HandshakeConfig struct { + // ProtocolVersion is the version that clients must match on to + // agree they can communicate. This should match the ProtocolVersion + // set on ClientConfig when using a plugin. + ProtocolVersion uint + + // MagicCookieKey and value are used as a very basic verification + // that a plugin is intended to be launched. This is not a security + // measure, just a UX feature. If the magic cookie doesn't match, + // we show human-friendly output. + MagicCookieKey string + MagicCookieValue string +} + +// ServeConfig configures what sorts of plugins are served. +type ServeConfig struct { + // HandshakeConfig is the configuration that must match clients. + HandshakeConfig + + // Plugins are the plugins that are served. + Plugins map[string]Plugin +} + +// Serve serves the plugins given by ServeConfig. +// +// Serve doesn't return until the plugin is done being executed. Any +// errors will be outputted to the log. +// +// This is the method that plugins should call in their main() functions. +func Serve(opts *ServeConfig) { + // Validate the handshake config + if opts.MagicCookieKey == "" || opts.MagicCookieValue == "" { + fmt.Fprintf(os.Stderr, + "Misconfigured ServeConfig given to serve this plugin: no magic cookie\n"+ + "key or value was set. Please notify the plugin author and report\n"+ + "this as a bug.\n") + os.Exit(1) + } + + // First check the cookie + if os.Getenv(opts.MagicCookieKey) != opts.MagicCookieValue { + fmt.Fprintf(os.Stderr, + "This binary is a plugin. These are not meant to be executed directly.\n"+ + "Please execute the program that consumes these plugins, which will\n"+ + "load any plugins automatically\n") + os.Exit(1) + } + + // Logging goes to the original stderr + log.SetOutput(os.Stderr) + + // Create our new stdout, stderr files. These will override our built-in + // stdout/stderr so that it works across the stream boundary. + stdout_r, stdout_w, err := os.Pipe() + if err != nil { + fmt.Fprintf(os.Stderr, "Error preparing plugin: %s\n", err) + os.Exit(1) + } + stderr_r, stderr_w, err := os.Pipe() + if err != nil { + fmt.Fprintf(os.Stderr, "Error preparing plugin: %s\n", err) + os.Exit(1) + } + + // Register a listener so we can accept a connection + listener, err := serverListener() + if err != nil { + log.Printf("[ERR] plugin: plugin init: %s", err) + return + } + defer listener.Close() + + // Create the channel to tell us when we're done + doneCh := make(chan struct{}) + + // Create the RPC server to dispense + server := &RPCServer{ + Plugins: opts.Plugins, + Stdout: stdout_r, + Stderr: stderr_r, + DoneCh: doneCh, + } + + // Output the address and service name to stdout so that core can bring it up. + log.Printf("[DEBUG] plugin: plugin address: %s %s\n", + listener.Addr().Network(), listener.Addr().String()) + fmt.Printf("%d|%d|%s|%s\n", + CoreProtocolVersion, + opts.ProtocolVersion, + listener.Addr().Network(), + listener.Addr().String()) + os.Stdout.Sync() + + // Eat the interrupts + ch := make(chan os.Signal, 1) + signal.Notify(ch, os.Interrupt) + go func() { + var count int32 = 0 + for { + <-ch + newCount := atomic.AddInt32(&count, 1) + log.Printf( + "[DEBUG] plugin: received interrupt signal (count: %d). Ignoring.", + newCount) + } + }() + + // Set our new out, err + os.Stdout = stdout_w + os.Stderr = stderr_w + + // Serve + go server.Accept(listener) + + // Wait for the graceful exit + <-doneCh +} + +func serverListener() (net.Listener, error) { + if runtime.GOOS == "windows" { + return serverListener_tcp() + } + + return serverListener_unix() +} + +func serverListener_tcp() (net.Listener, error) { + minPort, err := strconv.ParseInt(os.Getenv("PLUGIN_MIN_PORT"), 10, 32) + if err != nil { + return nil, err + } + + maxPort, err := strconv.ParseInt(os.Getenv("PLUGIN_MAX_PORT"), 10, 32) + if err != nil { + return nil, err + } + + for port := minPort; port <= maxPort; port++ { + address := fmt.Sprintf("127.0.0.1:%d", port) + listener, err := net.Listen("tcp", address) + if err == nil { + return listener, nil + } + } + + return nil, errors.New("Couldn't bind plugin TCP listener") +} + +func serverListener_unix() (net.Listener, error) { + tf, err := ioutil.TempFile("", "plugin") + if err != nil { + return nil, err + } + path := tf.Name() + + // Close the file and remove it because it has to not exist for + // the domain socket. + if err := tf.Close(); err != nil { + return nil, err + } + if err := os.Remove(path); err != nil { + return nil, err + } + + l, err := net.Listen("unix", path) + if err != nil { + return nil, err + } + + // Wrap the listener in rmListener so that the Unix domain socket file + // is removed on close. + return &rmListener{ + Listener: l, + Path: path, + }, nil +} + +// rmListener is an implementation of net.Listener that forwards most +// calls to the listener but also removes a file as part of the close. We +// use this to cleanup the unix domain socket on close. +type rmListener struct { + net.Listener + Path string +} + +func (l *rmListener) Close() error { + // Close the listener itself + if err := l.Listener.Close(); err != nil { + return err + } + + // Remove the file + return os.Remove(l.Path) +} -- cgit v1.2.3