Move lxc_attach from namespace.c to attach.c and rename it to lxc_attach_to_ns

Since lxc-attach helper functions now have an own source file, lxc_attach is
moved from namespace.c to attach.c and is renamed to lxc_attach_to_ns,
because that better reflects what the function does (attaching to a
container can also contain the setting of the process's personality, adding
it to the corresponding cgroups and dropping specific capabilities).

Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>

5 files changed, 38 insertions, 50 deletions

diff --git a/src/lxc/attach.c b/src/lxc/attach.c
index 254b185..33da411 100644
--- a/src/lxc/attach.c
+++ b/src/lxc/attach.c
@@ -226,6 +226,41 @@ int lxc_attach_proc_to_cgroups(pid_t pid, struct lxc_proc_context_info *ctx)
 	return 0;
 }
 
+int lxc_attach_to_ns(pid_t pid)
+{
+	char path[MAXPATHLEN];
+	char *ns[] = { "pid", "mnt", "net", "ipc", "uts" };
+	const int size = sizeof(ns) / sizeof(char *);
+	int fd[size];
+	int i;
+
+	snprintf(path, MAXPATHLEN, "/proc/%d/ns", pid);
+	if (access(path, X_OK)) {
+		ERROR("Does this kernel version support 'attach' ?");
+		return -1;
+	}
+
+	for (i = 0; i < size; i++) {
+		snprintf(path, MAXPATHLEN, "/proc/%d/ns/%s", pid, ns[i]);
+		fd[i] = open(path, O_RDONLY);
+		if (fd[i] < 0) {
+			SYSERROR("failed to open '%s'", path);
+			return -1;
+		}
+	}
+
+	for (i = 0; i < size; i++) {
+		if (setns(fd[i], 0)) {
+			SYSERROR("failed to set namespace '%s'", ns[i]);
+			return -1;
+		}
+
+		close(fd[i]);
+	}
+
+	return 0;
+}
+
 int lxc_attach_drop_privs(struct lxc_proc_context_info *ctx)
 {
 	int last_cap = lxc_caps_last_cap();
diff --git a/src/lxc/attach.h b/src/lxc/attach.h
index 7e67455..d2b7533 100644
--- a/src/lxc/attach.h
+++ b/src/lxc/attach.h
@@ -42,6 +42,7 @@ extern struct lxc_proc_context_info *lxc_proc_get_context_info(pid_t pid);
 extern void lxc_proc_free_context_info(struct lxc_proc_context_info *info);
 
 extern int lxc_attach_proc_to_cgroups(pid_t pid, struct lxc_proc_context_info *ctx);
+extern int lxc_attach_to_ns(pid_t other_pid);
 extern int lxc_attach_drop_privs(struct lxc_proc_context_info *ctx);
 
 #endif
diff --git a/src/lxc/lxc_attach.c b/src/lxc/lxc_attach.c
index ed3d5a4..c8643d1 100644
--- a/src/lxc/lxc_attach.c
+++ b/src/lxc/lxc_attach.c
@@ -30,9 +30,9 @@
 #include <sys/types.h>
 #include <sys/wait.h>
 
+#include "attach.h"
 #include "commands.h"
 #include "arguments.h"
-#include "namespace.h"
 #include "caps.h"
 #include "log.h"
 
@@ -85,7 +85,7 @@ int main(int argc, char *argv[], char *envp[])
 
 	curdir = get_current_dir_name();
 
-	ret = lxc_attach(pid);
+	ret = lxc_attach_to_ns(pid);
 	if (ret < 0) {
 		ERROR("failed to enter the namespace");
 		return -1;
diff --git a/src/lxc/namespace.c b/src/lxc/namespace.c
index 6512685..3e6fc3a 100644
--- a/src/lxc/namespace.c
+++ b/src/lxc/namespace.c
@@ -34,8 +34,6 @@
 #include "namespace.h"
 #include "log.h"
 
-#include "setns.h"
-
 lxc_log_define(lxc_namespace, lxc);
 
 struct clone_arg {
@@ -43,16 +41,6 @@ struct clone_arg {
 	void *arg;
 };
 
-int setns(int fd, int nstype)
-{
-#ifndef __NR_setns
-	errno = ENOSYS;
-	return -1;
-#else
-	return syscall(__NR_setns, fd, nstype);
-#endif
-}
-
 static int do_clone(void *arg)
 {
 	struct clone_arg *clone_arg = arg;
@@ -81,38 +69,3 @@ pid_t lxc_clone(int (*fn)(void *), void *arg, int flags)
 
 	return ret;
 }
-
-int lxc_attach(pid_t pid)
-{
-	char path[MAXPATHLEN];
-	char *ns[] = { "pid", "mnt", "net", "ipc", "uts" };
-	const int size = sizeof(ns) / sizeof(char *);
-	int fd[size];
-	int i;
-
-	sprintf(path, "/proc/%d/ns", pid);
-	if (access(path, X_OK)) {
-		ERROR("Does this kernel version support 'attach' ?");
-		return -1;
-	}
-
-	for (i = 0; i < size; i++) {
-		sprintf(path, "/proc/%d/ns/%s", pid, ns[i]);
-		fd[i] = open(path, O_RDONLY);
-		if (fd[i] < 0) {
-			SYSERROR("failed to open '%s'", path);
-			return -1;
-		}
-	}
-
-	for (i = 0; i < size; i++) {
-		if (setns(fd[i], 0)) {
-			SYSERROR("failed to set namespace '%s'", ns[i]);
-			return -1;
-		}
-
-		close(fd[i]);
-	}
-
-	return 0;
-}
diff --git a/src/lxc/namespace.h b/src/lxc/namespace.h
index 9c6b7ec..5442dd3 100644
--- a/src/lxc/namespace.h
+++ b/src/lxc/namespace.h
@@ -49,6 +49,5 @@
 #endif
 
 extern pid_t lxc_clone(int (*fn)(void *), void *arg, int flags);
-extern int lxc_attach(pid_t pid);
 
 #endif