From 3ab2a14928ccd8d1292c99dc7e88838c03cd64e2 Mon Sep 17 00:00:00 2001 From: Martchus Date: Sun, 8 Apr 2018 20:01:43 +0200 Subject: [PATCH] Add basic C bindings to start and stop Syncthing --- c-bindings/c_bindings.c | 11 +++ c-bindings/c_bindings.go | 182 +++++++++++++++++++++++++++++++++++++++ c-bindings/c_bindings.h | 11 +++ c-bindings/debug.go | 1 + 4 files changed, 205 insertions(+) create mode 100644 c-bindings/c_bindings.c create mode 100644 c-bindings/c_bindings.go create mode 100644 c-bindings/c_bindings.h create mode 120000 c-bindings/debug.go diff --git a/c-bindings/c_bindings.c b/c-bindings/c_bindings.c new file mode 100644 index 000000000..1dd98157f --- /dev/null +++ b/c-bindings/c_bindings.c @@ -0,0 +1,11 @@ +#include "c_bindings.h" + +libst_logging_callback_function_t libst_logging_callback_function = NULL; + +void libst_invoke_logging_callback(int log_level, const char *message, size_t message_size) +{ + if (!libst_logging_callback_function) { + return; + } + libst_logging_callback_function(log_level, message, message_size); +} diff --git a/c-bindings/c_bindings.go b/c-bindings/c_bindings.go new file mode 100644 index 000000000..8887ee0a3 --- /dev/null +++ b/c-bindings/c_bindings.go @@ -0,0 +1,182 @@ +package main + +import "os" +import "unsafe" +import "path/filepath" + +import "github.com/syncthing/syncthing/lib/build" +import "github.com/syncthing/syncthing/lib/config" +import "github.com/syncthing/syncthing/lib/events" +import "github.com/syncthing/syncthing/lib/fs" +import "github.com/syncthing/syncthing/lib/logger" +import "github.com/syncthing/syncthing/lib/locations" +import "github.com/syncthing/syncthing/lib/protocol" +import "github.com/syncthing/syncthing/lib/syncthing" + +// include header for required C helper functions (so the following comment is NO comment) + +// #include "c_bindings.h" +import "C" + +var theApp *syncthing.App +var myID protocol.DeviceID + +const ( + tlsDefaultCommonName = "syncthing" +) + +//export libst_own_device_id +func libst_own_device_id() string { + return myID.String() +} + +//export libst_init_logging +func libst_init_logging() { + l.AddHandler(logger.LevelVerbose, func(level logger.LogLevel, msg string) { + runes := []byte(msg) + length := len(runes) + if length <= 0 { + return + } + C.libst_invoke_logging_callback(C.int(level), (*C.char)(unsafe.Pointer(&runes[0])), C.size_t(len(runes))) + }) +} + +// C&P from main.go; used to ensure that the config directory exists +func ensureDir(dir string, mode fs.FileMode) error { + fs := fs.NewFilesystem(fs.FilesystemTypeBasic, dir) + err := fs.MkdirAll(".", mode) + if err != nil { + return err + } + + if fi, err := fs.Stat("."); err == nil { + // Apprently the stat may fail even though the mkdirall passed. If it + // does, we'll just assume things are in order and let other things + // fail (like loading or creating the config...). + currentMode := fi.Mode() & 0777 + if currentMode != mode { + err := fs.Chmod(".", mode) + // This can fail on crappy filesystems, nothing we can do about it. + if err != nil { + l.Warnln(err) + } + } + } + return nil +} + +//export libst_run_syncthing +func libst_run_syncthing(config_dir string, gui_address string, gui_api_key string, verbose bool, allow_newer_config bool, no_default_config bool, ensure_config_directory_exists bool) int { + // return if already running (for simplicity we only allow one Syncthing instance at at time for now) + if theApp != nil { + return 0 + } + + // set specified GUI address and API key + if gui_address != "" { + os.Setenv("STGUIADDRESS", gui_address) + } + if gui_api_key != "" { + os.Setenv("STGUIADDRESS", gui_api_key) + } + + // set specified config dir + if config_dir != "" { + if !filepath.IsAbs(config_dir) { + var err error + config_dir, err = filepath.Abs(config_dir) + if err != nil { + l.Warnln("Failed to make config path absolute:", err) + return 3 + } + } + if err := locations.SetBaseDir(locations.ConfigBaseDir, config_dir); err != nil { + l.Warnln(err) + return 3 + } + } + + // ensure that the config directory exists + if ensure_config_directory_exists { + if err := ensureDir(locations.GetBaseDir(locations.ConfigBaseDir), 0700); err != nil { + l.Warnln("Failed to create config directory:", err) + return 4 + } + } + + // ensure that we have a certificate and key + cert, certErr := syncthing.LoadOrGenerateCertificate( + locations.Get(locations.CertFile), + locations.Get(locations.KeyFile), + ) + if certErr != nil { + l.Warnln("Failed to load/generate certificate:", certErr) + return 1 + } + + evLogger := events.NewLogger() + go evLogger.Serve() + defer evLogger.Stop() + + // load config + cfg, cfgErr := syncthing.LoadConfigAtStartup(locations.Get(locations.ConfigFile), cert, evLogger, allow_newer_config, no_default_config) + if cfgErr != nil { + l.Warnln("Failed to initialize config:", cfgErr) + return 2 + } + + // open database + dbFile := locations.Get(locations.Database) + ldb, dbErr := syncthing.OpenDBBackend(dbFile, config.TuningAuto) + if dbErr != nil { + l.Warnln("Error opening database:", dbErr) + return 4 + } + + appOpts := syncthing.Options{ + AssetDir: os.Getenv("STGUIASSETS"), + ProfilerURL: os.Getenv("STPROFILER"), + NoUpgrade: true, + Verbose: verbose, + } + theApp = syncthing.New(cfg, ldb, evLogger, cert, appOpts) + + // start Syncthing and block until it has finished + returnCode := 0 + if err := theApp.Start(); err != nil { + returnCode = syncthing.ExitError.AsInt() + } + returnCode = theApp.Wait().AsInt(); + theApp = nil + return returnCode +} + +//export libst_stop_syncthing +func libst_stop_syncthing() int { + if theApp != nil { + return int(theApp.Stop(syncthing.ExitSuccess)) + } else { + return 0; + } +} + +//export libst_reset_database +func libst_reset_database() { + os.RemoveAll(locations.Get(locations.Database)) +} + +//export libst_syncthing_version +func libst_syncthing_version() *C.char { + return C.CString(build.Version) +} + +//export libst_long_syncthing_version +func libst_long_syncthing_version() *C.char { + return C.CString(build.LongVersion) +} + +func main() { + // prevent "runtime.main_main·f: function main is undeclared in the main package" +} + diff --git a/c-bindings/c_bindings.h b/c-bindings/c_bindings.h new file mode 100644 index 000000000..e4e32ecb3 --- /dev/null +++ b/c-bindings/c_bindings.h @@ -0,0 +1,11 @@ +#ifndef LIBSYNCTHING_INTERNAL_H +#define LIBSYNCTHING_INTERNAL_H + +#include + +// allow registration of callback function +typedef void (*libst_logging_callback_function_t) (int logLevel, const char *msg, size_t msgSize); +extern libst_logging_callback_function_t libst_logging_callback_function; +extern void libst_invoke_logging_callback(int log_level, const char *message, size_t message_size); + +#endif // LIBSYNCTHING_INTERNAL_H diff --git a/c-bindings/debug.go b/c-bindings/debug.go new file mode 120000 index 000000000..117c10801 --- /dev/null +++ b/c-bindings/debug.go @@ -0,0 +1 @@ +../cmd/syncthing/debug.go \ No newline at end of file