OS-4361 libzonecfg should be aware of branded zone native root
Reviewed by: Robert Mustacchi <rm@joyent.com>

@@ -18,10 +18,11 @@
  *
  * CDDL HEADER END
  */
 /*
  * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright 2015 Joyent, Inc.
  */
 
 
 /*
  * This module contains functions used for reading and writing the index file.

@@ -168,22 +169,44 @@
 
         return (ze);
 }
 
 static boolean_t
-get_index_path(char *path)
+path_common(char *path, size_t path_size, const char *stem)
 {
-        return (snprintf(path, MAXPATHLEN, "%s%s", zonecfg_root,
-            ZONE_INDEX_FILE) < MAXPATHLEN);
+        const char *native_root = zone_get_nroot();
+
+        if (native_root == NULL || zonecfg_in_alt_root()) {
+                /*
+                 * Do not prepend the native system root (e.g. "/native") if an
+                 * alternative configuration root has been selected.
+                 */
+                native_root = "";
+        }
+
+        return (snprintf(path, path_size, "%s%s%s", native_root, zonecfg_root,
+            stem) < path_size);
 }
 
+static boolean_t
+get_index_path(char *path, size_t path_size)
+{
+        return (path_common(path, path_size, ZONE_INDEX_FILE));
+}
+
+static boolean_t
+get_temp_path(char *path, size_t path_size)
+{
+        return (path_common(path, path_size, _PATH_TMPFILE));
+}
+
 FILE *
 setzoneent(void)
 {
         char path[MAXPATHLEN];
 
-        if (!get_index_path(path)) {
+        if (!get_index_path(path, sizeof (path))) {
                 errno = EINVAL;
                 return (NULL);
         }
         return (fopen(path, "r"));
 }

@@ -200,12 +223,11 @@
 {
         int lock_fd;
         struct flock lock;
         char path[MAXPATHLEN];
 
-        if (snprintf(path, sizeof (path), "%s%s", zonecfg_root,
-            ZONE_INDEX_LOCK_DIR) >= sizeof (path))
+        if (!path_common(path, sizeof (path), ZONE_INDEX_LOCK_DIR))
                 return (-1);
         if ((mkdir(path, S_IRWXU) == -1) && errno != EEXIST)
                 return (-1);
         if (strlcat(path, ZONE_INDEX_LOCK_FILE, sizeof (path)) >=
             sizeof (path))

@@ -267,17 +289,18 @@
  */
 int
 putzoneent(struct zoneent *ze, zoneent_op_t operation)
 {
         FILE *index_file, *tmp_file;
-        char *tmp_file_name, buf[MAX_INDEX_LEN];
+        char buf[MAX_INDEX_LEN];
         int tmp_file_desc, lock_fd, err;
         boolean_t exist, need_quotes;
         char *cp;
+        char tmp_path[MAXPATHLEN];
         char path[MAXPATHLEN];
         char uuidstr[UUID_PRINTABLE_STRING_LENGTH];
-        size_t tlen, namelen;
+        size_t namelen;
         const char *zone_name, *zone_state, *zone_path, *zone_uuid;
 
         assert(ze != NULL);
 
         /*

@@ -297,24 +320,18 @@
                 return (Z_INVAL);
 
         if ((lock_fd = lock_index_file()) == -1)
                 return (Z_LOCKING_FILE);
 
-        /* using sizeof gives us room for the terminating NUL byte as well */
-        tlen = sizeof (_PATH_TMPFILE) + strlen(zonecfg_root);
-        tmp_file_name = malloc(tlen);
-        if (tmp_file_name == NULL) {
+        if (!get_temp_path(tmp_path, sizeof (tmp_path))) {
                 (void) unlock_index_file(lock_fd);
                 return (Z_NOMEM);
         }
-        (void) snprintf(tmp_file_name, tlen, "%s%s", zonecfg_root,
-            _PATH_TMPFILE);
 
-        tmp_file_desc = mkstemp(tmp_file_name);
+        tmp_file_desc = mkstemp(tmp_path);
         if (tmp_file_desc == -1) {
-                (void) unlink(tmp_file_name);
-                free(tmp_file_name);
+                (void) unlink(tmp_path);
                 (void) unlock_index_file(lock_fd);
                 return (Z_TEMP_FILE);
         }
         (void) fchmod(tmp_file_desc, ZONE_INDEX_MODE);
         (void) fchown(tmp_file_desc, ZONE_INDEX_UID, ZONE_INDEX_GID);

@@ -321,11 +338,11 @@
         if ((tmp_file = fdopen(tmp_file_desc, "w")) == NULL) {
                 (void) close(tmp_file_desc);
                 err = Z_MISC_FS;
                 goto error;
         }
-        if (!get_index_path(path)) {
+        if (!get_index_path(path, sizeof (path))) {
                 err = Z_MISC_FS;
                 goto error;
         }
         if ((index_file = fopen(path, "r")) == NULL) {
                 err = Z_MISC_FS;

@@ -462,24 +479,22 @@
                 tmp_file = NULL;
                 err = Z_MISC_FS;
                 goto error;
         }
         tmp_file = NULL;
-        if (rename(tmp_file_name, path) == -1) {
+        if (rename(tmp_path, path) == -1) {
                 err = errno == EACCES ? Z_ACCES : Z_MISC_FS;
                 goto error;
         }
-        free(tmp_file_name);
         if (unlock_index_file(lock_fd) != Z_OK)
                 return (Z_UNLOCKING_FILE);
         return (Z_OK);
 
 error:
         if (index_file != NULL)
                 (void) fclose(index_file);
         if (tmp_file != NULL)
                 (void) fclose(tmp_file);
-        (void) unlink(tmp_file_name);
-        free(tmp_file_name);
+        (void) unlink(tmp_path);
         (void) unlock_index_file(lock_fd);
         return (err);
 }