lxc-unshare: accept multiple -s options

I would like to also automatically have /proc remounted, but that would require digging deeper into lxc_clone.

Mind you perhaps having NEWPID imply NEWNS should be done there, at src/lxc/namespace.c:lxc_clone anyway. I'm starting here... Won't be offended if it's rejected on those grounds :)

Signed-off-by Serge E. Hallyn<serue-r/[email protected]>

---
  src/lxc/lxc_unshare.c |    4 ++++
  1 files changed, 4 insertions(+), 0 deletions(-)

src/lxc/lxc_unshare.c +4 -0

index 8db1cb7..8531b59 100644
@@ -49,6 +49,7 @@ void usage(char *cmd)
  			"\t           MOUNT, PID, UTSNAME, IPC, USER, NETWORK\n");
  	fprintf(stderr, "\t -u<id>  : new id to be set if -s USER is specified\n");
  	fprintf(stderr, "\t if -s PID is specified,<command>  is mandatory)\n");
+	fprintf(stderr, "\t If -s PID is specified, then -s MOUNT is implied\n");
  	_exit(1);
  }
 

@@ -213,6 +214,9 @@ int main(int argc, char *argv[])
   	if (ret)
  		usage(argv[0]);
 
+	if (flags&  CLONE_NEWPID)
+		flags |= CLONE_NEWNS;
+
  	if (!(flags&  CLONE_NEWUSER)&&  uid != -1) {
  		ERROR("-u<uid>  needs -s USER option");
  		return 1;

(also remove -f from usage as it is not actually supported)

Signed-off-by Serge E. Hallyn<serue-r/[email protected]>

---
  src/lxc/lxc_unshare.c |   28 ++++++++++++++++++++++++++--
  1 files changed, 26 insertions(+), 2 deletions(-)

src/lxc/lxc_unshare.c +24 -1

index 10654f7..8db1cb7 100644
@@ -48,7 +48,7 @@ void usage(char *cmd)
  	fprintf(stderr, "\t -s flags: Ored list of flags to unshare:\n" \
  			"\t           MOUNT, PID, UTSNAME, IPC, USER, NETWORK\n");
  	fprintf(stderr, "\t -u<id>  : new id to be set if -s USER is specified\n");
-	fprintf(stderr, "\t if -f or -s PID is specified,<command>  is mandatory)\n");
+	fprintf(stderr, "\t if -s PID is specified,<command>  is mandatory)\n");
  	_exit(1);
  }
 

@@ -154,6 +154,29 @@ static int do_start(void *arg)
  	return 1;
  }
 
+void extend_namespaces(char **n, char *optarg)
+{
+	char *namespaces = *n;
+	int cont = 0, newlen = strlen(optarg) + 1; /* +1 for trailing \0 */
+
+	if (namespaces) {
+		cont = 1;
+		newlen += strlen(namespaces) + 1; /* +1 for '|' */
+	}
+
+	namespaces = realloc(namespaces, newlen);
+	if (!namespaces) {
+		perror("realloc");
+		exit(1);
+	}
+	if (cont)
+		sprintf(namespaces+strlen(namespaces), "|%s", optarg);
+	else
+		sprintf(namespaces, "%s", optarg);
+	namespaces[newlen-1] = '\0';
+	*n = namespaces;
+}
+
  int main(int argc, char *argv[])
  {
  	int opt, status;

Quoted 51 lines · Serge E. Hallyn

(also remove -f from usage as it is not actually supported)

Signed-off-by Serge E. Hallyn<serue-r/[email protected]>

---
 src/lxc/lxc_unshare.c |   28 ++++++++++++++++++++++++++--
 1 files changed, 26 insertions(+), 2 deletions(-)

src/lxc/lxc_unshare.c +24 -1

index 10654f7..8db1cb7 100644
@@ -48,7 +48,7 @@ void usage(char *cmd)
 	fprintf(stderr, "\t -s flags: Ored list of flags to unshare:\n" \
 			"\t           MOUNT, PID, UTSNAME, IPC, USER, NETWORK\n");
 	fprintf(stderr, "\t -u<id>  : new id to be set if -s USER is specified\n");
-	fprintf(stderr, "\t if -f or -s PID is specified,<command>  is mandatory)\n");
+	fprintf(stderr, "\t if -s PID is specified,<command>  is mandatory)\n");
 	_exit(1);
 }
 

@@ -154,6 +154,29 @@ static int do_start(void *arg)
 	return 1;
 }
 
+void extend_namespaces(char **n, char *optarg)
+{
+	char *namespaces = *n;
+	int cont = 0, newlen = strlen(optarg) + 1; /* +1 for trailing \0 */
+
+	if (namespaces) {
+		cont = 1;
+		newlen += strlen(namespaces) + 1; /* +1 for '|' */
+	}
+
+	namespaces = realloc(namespaces, newlen);
+	if (!namespaces) {
+		perror("realloc");
+		exit(1);
+	}
+	if (cont)
+		sprintf(namespaces+strlen(namespaces), "|%s", optarg);
+	else
+		sprintf(namespaces, "%s", optarg);
+	namespaces[newlen-1] = '\0';
+	*n = namespaces;
+}
+
 int main(int argc, char *argv[])
 {
 	int opt, status;

src/lxc/lxc_unshare.c int main(int argc, char *argv[]) · line 204

Quoted 9 lines

src/lxc/lxc_unshare.c +2 -1

@@ -174,7 +197,8 @@ int main(int argc, char *argv[])
 	while ((opt = getopt(argc, argv, "s:u:")) != -1) {
 		switch (opt) {
 		case 's':
-			namespaces = optarg;
+			extend_namespaces(&namespaces, optarg);
+			printf("namespaces is %s\n", namespaces);
 			break;
 		case 'u':
 			uid = lookup_user(optarg);

Hi Serge,

Sorry for the delay.

Is it possible to just kill the "Ored" option format and have only multiple "-s" options ? That will simplificate the code a lot.