introduce Rename and split Attach functions into multiple functions

.gitignore

@@ -21,6 +21,7 @@ examples/list
 examples/list_keys
 examples/list_snapshots
 examples/reboot
+examples/rename
 examples/restore_snapshot
 examples/shutdown
 examples/start

const.go

@@ -40,13 +40,14 @@ const (
 	errDaemonizeFailed               = "setting daemonize flag for container %q failed"
 	errDestroyFailed                 = "destroying the container %q failed"
 	errDestroySnapshotFailed         = "destroying the snapshot %q failed"
+	errExecuteFailed                 = "executing the command in a temporary container %q failed"
 	errFreezeFailed                  = "freezing the container %q failed"
-	errIPAddress                     = "getting IP address on the interface %s of the container %q failed"
-	errIPAddresses                   = "getting IP addresses of the container %q failed"
-	errIPv4Addresses                 = "getting IPv4 addresses of the container %q failed"
-	errIPv6Addresses                 = "getting IPv6 addresses of the container %q failed"
 	errInsufficientNumberOfArguments = "insufficient number of arguments were supplied"
 	errInterfaces                    = "getting interface names for the container %q failed"
+	errIPAddresses                   = "getting IP addresses of the container %q failed"
+	errIPAddress                     = "getting IP address on the interface %s of the container %q failed"
+	errIPv4Addresses                 = "getting IPv4 addresses of the container %q failed"
+	errIPv6Addresses                 = "getting IPv6 addresses of the container %q failed"
 	errLoadConfigFailed              = "loading config file for the container %q failed (path: %s)"
 	errMemLimit                      = "your kernel does not support cgroup memory controller"
 	errNewFailed                     = "allocating the container %q failed"
@@ -54,6 +55,7 @@ const (
 	errNotFrozen                     = "container %q is not frozen"
 	errNotRunning                    = "container %q is not running"
 	errRebootFailed                  = "rebooting the container %q failed"
+	errRenameFailed                  = "renaming the container %q failed"
 	errRestoreSnapshotFailed         = "restoring the container %q failed"
 	errSaveConfigFailed              = "saving config file for the container %q failed (path: %s)"
 	errSettingCgroupItemFailed       = "setting cgroup item for the container %q failed (key: %s, value: %s)"
@@ -63,7 +65,6 @@ const (
 	errSettingSwapLimitFailed        = "setting swap limit for the container %q failed"
 	errShutdownFailed                = "shutting down the container %q failed"
 	errStartFailed                   = "starting the container %q failed"
-	errExecuteFailed                 = "executing the command in a temporary container %q failed"
 	errStopFailed                    = "stopping the container %q failed"
 	errSwapLimit                     = "your kernel does not support cgroup swap controller"
 	errUnfreezeFailed                = "unfreezing the container %q failed"

container.go

@@ -468,6 +468,24 @@ func (lxc *Container) CloneToOverlayFS(name string) error {
 	return lxc.Clone(name, CloneSnapshot, OverlayFS)
 }
 
+// Rename renames the container
+func (lxc *Container) Rename(name string) error {
+	if err := lxc.ensureDefinedButNotRunning(); err != nil {
+		return err
+	}
+
+	lxc.mu.Lock()
+	defer lxc.mu.Unlock()
+
+	cname := C.CString(name)
+	defer C.free(unsafe.Pointer(cname))
+
+	if !bool(C.lxc_container_rename(lxc.container, cname)) {
+		return fmt.Errorf(errRenameFailed, C.GoString(lxc.container.name))
+	}
+	return nil
+}
+
 // Wait waits for container to reach a given state or timeouts
 func (lxc *Container) Wait(state State, timeout int) bool {
 	lxc.mu.Lock()
@@ -836,9 +854,8 @@ func (lxc *Container) Console(ttynum, stdinfd, stdoutfd, stderrfd, escape int) e
 	return nil
 }
 
-// AttachRunShell runs a shell inside the container
-func (lxc *Container) AttachRunShell() error {
-	// FIXME: support lxc_attach_options_t, currently we use LXC_ATTACH_OPTIONS_DEFAULT
+// AttachShell runs a shell inside the container
+func (lxc *Container) AttachShell() error {
 	if err := lxc.ensureDefinedAndRunning(); err != nil {
 		return err
 	}
@@ -846,16 +863,29 @@ func (lxc *Container) AttachRunShell() error {
 	lxc.mu.Lock()
 	defer lxc.mu.Unlock()
 
-	ret := int(C.lxc_container_attach(lxc.container))
-	if ret < 0 {
+	if int(C.lxc_container_attach(lxc.container, false)) < 0 {
 		return fmt.Errorf(errAttachFailed, C.GoString(lxc.container.name))
 	}
 	return nil
 }
 
-// AttachRunCommand runs the user specified command inside the container and waits it to exit
-func (lxc *Container) AttachRunCommand(args ...string) error {
-	// FIXME: support lxc_attach_options_t, currently we use LXC_ATTACH_OPTIONS_DEFAULT
+// AttachShellWithClearEnvironment runs a shell inside the container and clears all environment variables before attaching
+func (lxc *Container) AttachShellWithClearEnvironment() error {
+	if err := lxc.ensureDefinedAndRunning(); err != nil {
+		return err
+	}
+
+	lxc.mu.Lock()
+	defer lxc.mu.Unlock()
+
+	if int(C.lxc_container_attach(lxc.container, true)) < 0 {
+		return fmt.Errorf(errAttachFailed, C.GoString(lxc.container.name))
+	}
+	return nil
+}
+
+// RunCommand runs the user specified command inside the container and waits it to exit
+func (lxc *Container) RunCommand(args ...string) error {
 	if args == nil {
 		return fmt.Errorf(errInsufficientNumberOfArguments)
 	}
@@ -870,8 +900,29 @@ func (lxc *Container) AttachRunCommand(args ...string) error {
 	cargs := makeNullTerminatedArgs(args)
 	defer freeNullTerminatedArgs(cargs, len(args))
 
-	ret := int(C.lxc_container_attach_run_wait(lxc.container, cargs))
-	if ret < 0 {
+	if int(C.lxc_container_attach_run_wait(lxc.container, false, cargs)) < 0 {
+		return fmt.Errorf(errAttachFailed, C.GoString(lxc.container.name))
+	}
+	return nil
+}
+
+// RunCommandWithClearEnvironment runs the user specified command inside the container and waits it to exit. It also clears all environment variables before attaching.
+func (lxc *Container) RunCommandWithClearEnvironment(args ...string) error {
+	if args == nil {
+		return fmt.Errorf(errInsufficientNumberOfArguments)
+	}
+
+	if err := lxc.ensureDefinedAndRunning(); err != nil {
+		return err
+	}
+
+	lxc.mu.Lock()
+	defer lxc.mu.Unlock()
+
+	cargs := makeNullTerminatedArgs(args)
+	defer freeNullTerminatedArgs(cargs, len(args))
+
+	if int(C.lxc_container_attach_run_wait(lxc.container, true, cargs)) < 0 {
 		return fmt.Errorf(errAttachFailed, C.GoString(lxc.container.name))
 	}
 	return nil

examples/attach.go

@@ -32,11 +32,13 @@ import (
 var (
 	lxcpath string
 	name    string
+	clear   bool
 )
 
 func init() {
 	flag.StringVar(&lxcpath, "lxcpath", lxc.DefaultConfigPath(), "Use specified container path")
 	flag.StringVar(&name, "name", "rubik", "Name of the original container")
+	flag.BoolVar(&clear, "clear", false, "Attach with clear environment")
 	flag.Parse()
 }
 
@@ -47,13 +49,26 @@ func main() {
 	}
 	defer lxc.PutContainer(c)
 
-	log.Printf("AttachRunShell\n")
-	if err := c.AttachRunShell(); err != nil {
-		log.Fatalf("ERROR: %s\n", err.Error())
-	}
+	if clear {
+		log.Printf("AttachShellWithClearEnvironment\n")
+		if err := c.AttachShellWithClearEnvironment(); err != nil {
+			log.Fatalf("ERROR: %s\n", err.Error())
+		}
 
-	log.Printf("AttachRunCommand\n")
-	if err := c.AttachRunCommand("uname", "-a"); err != nil {
-		log.Fatalf("ERROR: %s\n", err.Error())
+		log.Printf("RunCommandWithClearEnvironment\n")
+		if err := c.RunCommandWithClearEnvironment("uname", "-a"); err != nil {
+			log.Fatalf("ERROR: %s\n", err.Error())
+		}
+
+	} else {
+		log.Printf("AttachShell\n")
+		if err := c.AttachShell(); err != nil {
+			log.Fatalf("ERROR: %s\n", err.Error())
+		}
+
+		log.Printf("RunCommand\n")
+		if err := c.RunCommand("uname", "-a"); err != nil {
+			log.Fatalf("ERROR: %s\n", err.Error())
+		}
 	}
 }

examples/rename.go

@@ -0,0 +1,56 @@
+/*
+ * rename.go
+ *
+ * Copyright © 2013, S.Çağlar Onur
+ *
+ * Authors:
+ * S.Çağlar Onur <caglar@10ur.org>
+ *
+ * This library is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+package main
+
+import (
+	"flag"
+	"log"
+
+	"github.com/caglar10ur/lxc"
+)
+
+var (
+	lxcpath string
+	newname string
+	name    string
+)
+
+func init() {
+	flag.StringVar(&lxcpath, "lxcpath", lxc.DefaultConfigPath(), "Use specified container path")
+	flag.StringVar(&newname, "newname", "kibur", "New name of the container")
+	flag.StringVar(&name, "name", "rubik", "Name of the container")
+	flag.Parse()
+}
+
+func main() {
+	c, err := lxc.NewContainer(name, lxcpath)
+	if err != nil {
+		log.Fatalf("ERROR: %s\n", err.Error())
+	}
+	defer lxc.PutContainer(c)
+
+	log.Printf("Renaming container to %s...\n", newname)
+	if err := c.Rename(newname); err != nil {
+		log.Printf("ERROR: %s\n", err.Error())
+	}
+}

lxc.c

@@ -172,10 +172,15 @@ char** lxc_container_get_ips(struct lxc_container *c, const char *interface, con
 	return c->get_ips(c, interface, family, scope);
 }
 
-int lxc_container_attach(struct lxc_container *c) {
+int lxc_container_attach(struct lxc_container *c, bool clear_env) {
 	int ret;
 	pid_t pid;
-	lxc_attach_options_t default_options = LXC_ATTACH_OPTIONS_DEFAULT;
+	lxc_attach_options_t attach_options = LXC_ATTACH_OPTIONS_DEFAULT;
+
+	attach_options.env_policy = LXC_ATTACH_KEEP_ENV;
+	if (clear_env) {
+		attach_options.env_policy = LXC_ATTACH_CLEAR_ENV;
+	}
 
 	/*
 	   remount_sys_proc
@@ -199,9 +204,9 @@ int lxc_container_attach(struct lxc_container *c) {
 
 	   default_options.extra_env_vars = extra_env;
 	   default_options.extra_keep_env = extra_keep;
-	   */
+	*/
 
-	ret = c->attach(c, lxc_attach_run_shell, NULL, &default_options, &pid);
+	ret = c->attach(c, lxc_attach_run_shell, NULL, &attach_options, &pid);
 	if (ret < 0)
 		return -1;
 
@@ -215,11 +220,16 @@ int lxc_container_attach(struct lxc_container *c) {
 	return -1;
 }
 
-int lxc_container_attach_run_wait(struct lxc_container *c, const char * const argv[]) {
+int lxc_container_attach_run_wait(struct lxc_container *c, bool clear_env, const char * const argv[]) {
 	int ret;
-	lxc_attach_options_t default_options = LXC_ATTACH_OPTIONS_DEFAULT;
+	lxc_attach_options_t attach_options = LXC_ATTACH_OPTIONS_DEFAULT;
 
-	ret = c->attach_run_wait(c, &default_options, argv[0], argv);
+	attach_options.env_policy = LXC_ATTACH_KEEP_ENV;
+	if (clear_env) {
+		attach_options.env_policy = LXC_ATTACH_CLEAR_ENV;
+	}
+
+	ret = c->attach_run_wait(c, &attach_options, argv[0], argv);
 	if (WIFEXITED(ret) && WEXITSTATUS(ret) == 255)
 		return -1;
 	return ret;
@@ -252,3 +262,7 @@ bool lxc_container_add_device_node(struct lxc_container *c, const char *src_path
 bool lxc_container_remove_device_node(struct lxc_container *c, const char *src_path, const char *dest_path) {
 	return c->remove_device_node(c, src_path, dest_path);
 }
+
+bool lxc_container_rename(struct lxc_container *c, const char *newname) {
+	return c->rename(c, newname);
+}

lxc.h

@@ -17,6 +17,7 @@ extern bool lxc_container_load_config(struct lxc_container *c, const char *alt_f
 extern bool lxc_container_may_control(struct lxc_container *c);
 extern bool lxc_container_reboot(struct lxc_container *c);
 extern bool lxc_container_remove_device_node(struct lxc_container *c, const char *src_path, const char *dest_path);
+extern bool lxc_container_rename(struct lxc_container *c, const char *newname);
 extern bool lxc_container_running(struct lxc_container *c);
 extern bool lxc_container_save_config(struct lxc_container *c, const char *alt_file);
 extern bool lxc_container_set_cgroup_item(struct lxc_container *c, const char *key, const char *value);
@@ -39,8 +40,8 @@ extern char** lxc_container_get_ips(struct lxc_container *c, const char *interfa
 extern char* lxc_container_get_keys(struct lxc_container *c, const char *key);
 extern const char* lxc_container_get_config_path(struct lxc_container *c);
 extern const char* lxc_container_state(struct lxc_container *c);
-extern int lxc_container_attach_run_wait(struct lxc_container *c, const char * const argv[]);
-extern int lxc_container_attach(struct lxc_container *c);
+extern int lxc_container_attach_run_wait(struct lxc_container *c, bool clear_env, const char * const argv[]);
+extern int lxc_container_attach(struct lxc_container *c, bool clear_env);
 extern int lxc_container_console_getfd(struct lxc_container *c, int ttynum);
 extern int lxc_container_snapshot_list(struct lxc_container *c, struct lxc_snapshot **ret);
 extern int lxc_container_snapshot(struct lxc_container *c);