conf: lxc_map_ids() non-functional changes

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

diff --git a/src/lxc/conf.c b/src/lxc/conf.c
index 530a57ed15859970f89627580029a0e9008dca34..afae3ca5d9fd65b545b7f4ca9caeafdd051912d7 100644 (file)
--- a/src/lxc/conf.c
+++ b/src/lxc/conf.c
@@ -3321,11 +3321,13 @@ static int write_id_mapping(enum idtype idtype, pid_t pid, const char *buf,
 
 int lxc_map_ids(struct lxc_list *idmap, pid_t pid)
 {
-       struct lxc_list *iterator;
        struct id_map *map;
-       int ret = 0, use_shadow = 0;
+       struct lxc_list *iterator;
        enum idtype type;
-       char *buf = NULL, *pos, *cmdpath = NULL;
+       char *pos;
+       char *buf = NULL, *cmdpath = NULL;
+       bool use_shadow = false;
+       int ret = 0;
 
        /*
         * If newuidmap exists, that is, if shadow is handing out subuid
@@ -3335,7 +3337,7 @@ int lxc_map_ids(struct lxc_list *idmap, pid_t pid)
         */
        cmdpath = on_path("newuidmap", NULL);
        if (cmdpath) {
-               use_shadow = 1;
+               use_shadow = true;
                free(cmdpath);
        }
 
@@ -3344,50 +3346,51 @@ int lxc_map_ids(struct lxc_list *idmap, pid_t pid)
                return -1;
        }
 
-       for(type = ID_TYPE_UID; type <= ID_TYPE_GID; type++) {
+       for (type = ID_TYPE_UID; type <= ID_TYPE_GID; type++) {
                int left, fill;
-               int had_entry = 0;
+               bool had_entry = false;
                if (!buf) {
-                       buf = pos = malloc(4096);
+                       buf = pos = malloc(LXC_IDMAPLEN);
                        if (!buf)
                                return -ENOMEM;
                }
                pos = buf;
                if (use_shadow)
-                       pos += sprintf(buf, "new%cidmap %d",
-                               type == ID_TYPE_UID ? 'u' : 'g',
-                               pid);
+                       pos += sprintf(buf, "new%cidmap %d", type == ID_TYPE_UID ? 'u' : 'g', pid);
 
                lxc_list_for_each(iterator, idmap) {
-                       /* The kernel only takes <= 4k for writes to /proc/<nr>/[ug]id_map */
+                       /* The kernel only takes <= 4k for writes to
+                        * /proc/<nr>/[ug]id_map
+                        */
                        map = iterator->elem;
                        if (map->idtype != type)
                                continue;
 
-                       had_entry = 1;
-                       left = 4096 - (pos - buf);
+                       had_entry = true;
+
+                       left = LXC_IDMAPLEN - (pos - buf);
                        fill = snprintf(pos, left, "%s%lu %lu %lu%s",
-                                       use_shadow ? " " : "",
-                                       map->nsid, map->hostid, map->range,
+                                       use_shadow ? " " : "", map->nsid,
+                                       map->hostid, map->range,
                                        use_shadow ? "" : "\n");
                        if (fill <= 0 || fill >= left)
-                               SYSERROR("snprintf failed, too many mappings");
+                               SYSERROR("Too many {g,u}id mappings defined.");
+
                        pos += fill;
                }
                if (!had_entry)
                        continue;
 
                if (!use_shadow) {
-                       ret = write_id_mapping(type, pid, buf, pos-buf);
+                       ret = write_id_mapping(type, pid, buf, pos - buf);
                } else {
-                       left = 4096 - (pos - buf);
+                       left = LXC_IDMAPLEN - (pos - buf);
                        fill = snprintf(pos, left, "\n");
                        if (fill <= 0 || fill >= left)
-                               SYSERROR("snprintf failed, too many mappings");
+                               SYSERROR("Too many {g,u}id mappings defined.");
                        pos += fill;
                        ret = system(buf);
                }
-
                if (ret)
                        break;
        }

diff --git a/src/lxc/utils.h b/src/lxc/utils.h
index 2b56905cb99e0beabdb076455649ea254c7dd923..d1966ff75a88cab3dc7b53665796cc858afa1c5d 100644 (file)
--- a/src/lxc/utils.h
+++ b/src/lxc/utils.h
@@ -39,6 +39,7 @@
 /* Maximum number for 64 bit integer is a string with 21 digits: 2^64 - 1 = 21 */
 #define LXC_NUMSTRLEN64 21
 #define LXC_LINELEN 4096
+#define LXC_IDMAPLEN 4096
 
 /* returns 1 on success, 0 if there were any failures */
 extern int lxc_rmdir_onedev(char *path, const char *exclude);