refactor string conf items into common function

- When doing the selinux change, I noticed that there was a lot of
  duplication of code in handing string configuration items, so I
  refactored this into a common function.

- Added a config_string_max that can be passed a maximum acceptable
  length, used to limit ttydir to NAME_MAX.

- The behavior of config_seccomp was different than other strings: if the
  item was already defined, then the second attempt to set it would fail
  instead of just replacing the value. Changed to just replace the value.

- Remove unused key and lxc_conf arguments to config_path_item().

Signed-off-by: Dwight Engen <dwight.engen@oracle.com>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>
Signed-off-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>

diff --git a/src/lxc/confile.c b/src/lxc/confile.c
index ee2832ce5404b8dc68e39d3c611c68c9ff85c8a7..a31479ed0d31ab227712b8a1e3f05e1538d21720 100644 (file)
--- a/src/lxc/confile.c
+++ b/src/lxc/confile.c
@@ -212,6 +212,41 @@ int lxc_listconfigs(char *retv, int inlen)
        return fulllen;
 }
 
+static int config_string_item(char **conf_item, const char *value)
+{
+       char *new_value;
+
+       if (!value || strlen(value) == 0)
+               return 0;
+
+       new_value = strdup(value);
+       if (!new_value) {
+               SYSERROR("failed to strdup '%s': %m", value);
+               return -1;
+       }
+
+       if (*conf_item)
+               free(*conf_item);
+       *conf_item = new_value;
+       return 0;
+}
+
+static int config_string_item_max(char **conf_item, const char *value,
+                                 size_t max)
+{
+       if (strlen(value) >= max) {
+               ERROR("%s is too long (>= %lu)", value, max);
+               return -1;
+       }
+
+       return config_string_item(conf_item, value);
+}
+
+static int config_path_item(char **conf_item, const char *value)
+{
+       return config_string_item_max(conf_item, value, PATH_MAX);
+}
+
 /*
  * config entry is something like "lxc.network.0.ipv4"
  * the key 'lxc.network.' was found.  So we make sure next
@@ -535,22 +570,12 @@ static int config_network_hwaddr(const char *key, const char *value,
                                 struct lxc_conf *lxc_conf)
 {
        struct lxc_netdev *netdev;
-       char *hwaddr;
 
        netdev = network_netdev(key, value, &lxc_conf->network);
        if (!netdev)
                return -1;
 
-       hwaddr = strdup(value);
-       if (!hwaddr) {
-               SYSERROR("failed to dup string '%s'", value);
-               return -1;
-       }
-
-       if (netdev->hwaddr)
-               free(netdev->hwaddr);
-       netdev->hwaddr = hwaddr;
-       return 0;
+       return config_string_item(&netdev->hwaddr, value);
 }
 
 static int config_network_vlan_id(const char *key, const char *value,
@@ -572,22 +597,12 @@ static int config_network_mtu(const char *key, const char *value,
                              struct lxc_conf *lxc_conf)
 {
        struct lxc_netdev *netdev;
-       char *mtu;
 
        netdev = network_netdev(key, value, &lxc_conf->network);
        if (!netdev)
                return -1;
 
-       mtu = strdup(value);
-       if (!mtu) {
-               SYSERROR("failed to dup string '%s'", value);
-               return -1;
-       }
-
-       if (netdev->mtu)
-               free(netdev->mtu);
-       netdev->mtu = mtu;
-       return 0;
+       return config_string_item(&netdev->mtu, value);
 }
 
 static int config_network_ipv4(const char *key, const char *value,
@@ -856,23 +871,7 @@ static int add_hook(struct lxc_conf *lxc_conf, int which, char *hook)
 static int config_seccomp(const char *key, const char *value,
                                 struct lxc_conf *lxc_conf)
 {
-       char *path;
-
-       if (lxc_conf->seccomp) {
-               ERROR("seccomp already defined");
-               return -1;
-       }
-       path = strdup(value);
-       if (!path) {
-               SYSERROR("failed to strdup '%s': %m", value);
-               return -1;
-       }
-
-       if (lxc_conf->seccomp)
-               free(lxc_conf->seccomp);
-       lxc_conf->seccomp = path;
-
-       return 0;
+       return config_path_item(&lxc_conf->seccomp, value);
 }
 
 static int config_hook(const char *key, const char *value,
@@ -938,21 +937,7 @@ static int config_tty(const char *key, const char *value,
 static int config_ttydir(const char *key, const char *value,
                          struct lxc_conf *lxc_conf)
 {
-       char *path;
-
-       if (!value || strlen(value) == 0)
-               return 0;
-       path = strdup(value);
-       if (!path) {
-               SYSERROR("failed to strdup '%s': %m", value);
-               return -1;
-       }
-
-       if (lxc_conf->ttydir)
-               free(lxc_conf->ttydir);
-       lxc_conf->ttydir = path;
-
-       return 0;
+       return config_string_item_max(&lxc_conf->ttydir, value, NAME_MAX+1);
 }
 
 static int config_kmsg(const char *key, const char *value,
@@ -968,52 +953,26 @@ static int config_kmsg(const char *key, const char *value,
 static int config_lsm_aa_profile(const char *key, const char *value,
                                 struct lxc_conf *lxc_conf)
 {
-       char *path;
-
-       if (!value || strlen(value) == 0)
-               return 0;
-       path = strdup(value);
-       if (!path) {
-               SYSERROR("failed to strdup '%s': %m", value);
-               return -1;
-       }
-
-       if (lxc_conf->lsm_aa_profile)
-               free(lxc_conf->lsm_aa_profile);
-       lxc_conf->lsm_aa_profile = path;
-
-       return 0;
+       return config_string_item(&lxc_conf->lsm_aa_profile, value);
 }
 
 static int config_lsm_se_context(const char *key, const char *value,
                                 struct lxc_conf *lxc_conf)
 {
-       char *path;
-
-       if (!value || strlen(value) == 0)
-               return 0;
-       path = strdup(value);
-       if (!path) {
-               SYSERROR("failed to strdup '%s': %m", value);
-               return -1;
-       }
-
-       if (lxc_conf->lsm_se_context)
-               free(lxc_conf->lsm_se_context);
-       lxc_conf->lsm_se_context = path;
-
-       return 0;
+       return config_string_item(&lxc_conf->lsm_se_context, value);
 }
 
 static int config_logfile(const char *key, const char *value,
                             struct lxc_conf *lxc_conf)
 {
+       int ret;
+
        // store these values in the lxc_conf, and then try to set for
        // actual current logging.
-       if (lxc_conf->logfile)
-               free(lxc_conf->logfile);
-       lxc_conf->logfile = strdup(value);
-       return lxc_log_set_file(value);
+       ret = config_path_item(&lxc_conf->logfile, value);
+       if (ret == 0)
+               ret = lxc_log_set_file(lxc_conf->logfile);
+       return ret;
 }
 
 static int config_loglevel(const char *key, const char *value,
@@ -1224,31 +1183,10 @@ out:
        return -1;
 }
 
-static int config_path_item(const char *key, const char *value,
-                           struct lxc_conf *lxc_conf, char **conf_item)
-{
-       char *valdup;
-       if (strlen(value) >= MAXPATHLEN) {
-               ERROR("%s path is too long", value);
-               return -1;
-       }
-
-       valdup = strdup(value);
-       if (!valdup) {
-               SYSERROR("failed to duplicate string %s", value);
-               return -1;
-       }
-       if (*conf_item)
-               free(*conf_item);
-       *conf_item = valdup;
-
-       return 0;
-}
-
 static int config_fstab(const char *key, const char *value,
                        struct lxc_conf *lxc_conf)
 {
-       return config_path_item(key, value, lxc_conf, &lxc_conf->fstab);
+       return config_path_item(&lxc_conf->fstab, value);
 }
 
 static int config_mount_auto(const char *key, const char *value,
@@ -1455,19 +1393,7 @@ static int config_cap_drop(const char *key, const char *value,
 static int config_console(const char *key, const char *value,
                          struct lxc_conf *lxc_conf)
 {
-       char *path;
-
-       path = strdup(value);
-       if (!path) {
-               SYSERROR("failed to strdup '%s': %m", value);
-               return -1;
-       }
-
-       if (lxc_conf->console.path)
-               free(lxc_conf->console.path);
-       lxc_conf->console.path = path;
-
-       return 0;
+       return config_path_item(&lxc_conf->console.path, value);
 }
 
 static int config_includefile(const char *key, const char *value,
@@ -1479,19 +1405,19 @@ static int config_includefile(const char *key, const char *value,
 static int config_rootfs(const char *key, const char *value,
                         struct lxc_conf *lxc_conf)
 {
-       return config_path_item(key, value, lxc_conf, &lxc_conf->rootfs.path);
+       return config_path_item(&lxc_conf->rootfs.path, value);
 }
 
 static int config_rootfs_mount(const char *key, const char *value,
                               struct lxc_conf *lxc_conf)
 {
-       return config_path_item(key, value, lxc_conf, &lxc_conf->rootfs.mount);
+       return config_path_item(&lxc_conf->rootfs.mount, value);
 }
 
 static int config_pivotdir(const char *key, const char *value,
                           struct lxc_conf *lxc_conf)
 {
-       return config_path_item(key, value, lxc_conf, &lxc_conf->rootfs.pivot);
+       return config_path_item(&lxc_conf->rootfs.pivot, value);
 }
 
 static int config_utsname(const char *key, const char *value,