Cleanup directories before restoring a snapshot

doc/66-snapshot.md

@@ -104,8 +104,6 @@ This subcommand restores a previously created snapshot called *name*.
 
 You can get a list of available snapshot invocating the [list](#list) subcommand.
 
-The restoration process does not remove existing elements; instead, it overwrites any matching elements found in both the snapshot directory and the corresponding directory on the host
-
 #### Options
 
 - **-h**: prints this help.

src/include/66/66.h

@@ -30,6 +30,7 @@
 #include <66/resolve.h>
 #include <66/sanitize.h>
 #include <66/service.h>
+#include <66/snapshot.h>
 #include <66/ssexec.h>
 #include <66/state.h>
 #include <66/svc.h>

src/include/66/snapshot.h

+/*
+ * snapshot.h
+ *
+ * Copyright (c) 2018-2024 Eric Vidal <eric@obarun.org>
+ *
+ * All rights reserved.
+ *
+ * This file is part of Obarun. It is subject to the license terms in
+ * the LICENSE file found in the top-level directory of this
+ * distribution.
+ * This file may not be copied, modified, propagated, or distributed
+ * except according to the terms contained in the LICENSE file./
+ */
+
+#ifndef SS_SNAPSHOT_H
+#define SS_SNAPSHOT_H
+
+#include <66/config.h>
+
+typedef struct snapshot_list_s snapshot_list_t ;
+struct snapshot_list_s
+{
+    char *name ;
+} ;
+
+extern snapshot_list_t snapshot_root_list[] ;
+
+extern snapshot_list_t snapshot_user_list[] ;
+
+#endif

src/lib66/exec/ssexec_snapshot_create.c

@@ -25,22 +25,15 @@
 #include <skalibs/sgetopt.h>
 #include <skalibs/djbunix.h>
 
+#include <66/snapshot.h>
 #include <66/ssexec.h>
 #include <66/constants.h>
 #include <66/utils.h>
 
-typedef struct snapshot_list_s snapshot_list_t ;
-struct snapshot_list_s
-{
-    char *name ;
-} ;
-
 snapshot_list_t snapshot_root_list[] = {
     { .name = SS_SKEL_DIR },
     { .name = SS_SERVICE_SYSDIR },
-    { .name = SS_SERVICE_SYSDIR_USER },
     { .name = SS_SERVICE_ADMDIR },
-    { .name = SS_SERVICE_ADMDIR_USER },
     { .name = SS_SERVICE_ADMCONFDIR },
     { .name = SS_SCRIPT_SYSDIR },
     { .name = SS_SEED_SYSDIR },

src/lib66/exec/ssexec_snapshot_restore.c

@@ -26,13 +26,52 @@
 #include <skalibs/djbunix.h>
 
 #include <66/ssexec.h>
+#include <66/snapshot.h>
 #include <66/constants.h>
 
+static void snapshot_remove_directory(ssexec_t *info, char const *target)
+{
+    size_t pos = 0 ;
+    snapshot_list_t *list = info->owner ? snapshot_user_list : snapshot_root_list ;
+    _alloc_stk_(stk, SS_MAX_PATH_LEN) ;
+
+    while(list[pos].name) {
+
+        if (!info->owner) {
+
+            auto_strings(stk.s, list[pos].name) ;
+
+        } else {
+
+            auto_strings(stk.s, target, list[pos].name) ;
+        }
+
+        log_trace("remove directory: ", stk.s) ;
+        if (!dir_rm_rf(stk.s))
+            log_warnusys("remove directory: ", stk.s) ;
+
+        pos++ ;
+    }
+
+    if (!info->owner) {
+
+        auto_strings(stk.s, SS_SYSTEM_DIR, SS_SYSTEM) ;
+
+    } else {
+
+        auto_strings(stk.s, target, SS_USER_DIR, SS_SYSTEM) ;
+    }
+
+    log_trace("remove directory: ", stk.s) ;
+    if (!dir_rm_rf(stk.s))
+        log_warnusys("remove directory: ", stk.s) ;
+}
+
 int ssexec_snapshot_restore(int argc, char const *const *argv, ssexec_t *info)
 {
     log_flow() ;
 
-    size_t pos = 0 ;
+    size_t pos = 0, dlen = 0 ;
     char const *snapname = 0 ;
     char const *exclude[1] = { 0 } ;
     _alloc_stk_(snapdir, SS_MAX_PATH_LEN) ;
@@ -74,44 +113,39 @@ int ssexec_snapshot_restore(int argc, char const *const *argv, ssexec_t *info)
     if (!sastr_dir_get(&sa, snapdir.s, exclude, S_IFDIR))
         log_dieusys(LOG_EXIT_SYS, "list snapshot directory: ", snapdir.s) ;
 
-    FOREACH_SASTR(&sa, pos) {
+    if (!info->owner) {
 
-        auto_strings(src.s, snapdir.s, "/", sa.s + pos) ;
+        auto_strings(dst.s, "/") ;
 
-        if (!info->owner) {
+    } else {
 
-            auto_strings(dst.s, "/", sa.s + pos) ;
+        int e = errno ;
+        struct passwd *st = getpwuid(info->owner) ;
+        errno = 0 ;
+        if (!st) {
+            if (!errno) errno = ESRCH ;
+            return 0 ;
+        }
+        errno = e ;
+        if (st->pw_dir == NULL)
+            log_warnusys(LOG_EXIT_ZERO, "get home directory") ;
 
-        } else {
+        auto_strings(dst.s, st->pw_dir, "/") ;
+    }
 
-            int e = errno ;
-            struct passwd *st = getpwuid(info->owner) ;
-            errno = 0 ;
-            if (!st) {
-                if (!errno) errno = ESRCH ;
-                return 0 ;
-            }
-            errno = e ;
-            if (st->pw_dir == NULL)
-                log_warnusys(LOG_EXIT_ZERO, "get home directory") ;
+    dlen = strlen(dst.s) ;
 
-            auto_strings(dst.s, st->pw_dir, "/", sa.s + pos) ;
-        }
+    snapshot_remove_directory(info, dst.s) ;
 
-        log_trace("copy: ", src.s , " to: ", dst.s) ;
-        if (!hiercopy(src.s, dst.s))
-            log_dieusys(LOG_EXIT_SYS, "copy: ", src.s," to: ", dst.s) ;
-    }
+    FOREACH_SASTR(&sa, pos) {
 
-    auto_strings(src.s, snapdir.s, "/", SS_SYSTEM, "/.version") ;
+        auto_strings(src.s, snapdir.s, "/", sa.s + pos) ;
 
-    /** remove .version file if it doesn't exist at snapshot dir.
-     * Typically version under 0.8.0.0 do not have this file.*/
-    if (access(src.s, F_OK) < 0) {
-        auto_strings(src.s, info->base.s, SS_SYSTEM, "/.version") ;
+        auto_strings(dst.s + dlen, sa.s + pos) ;
 
-        if (!dir_rm_rf(src.s))
-            log_warnusys("remove file: ", src.s) ;
+        log_trace("copy: ", src.s , " to: ", dst.s) ;
+        if (!hiercopy(src.s, dst.s))
+            log_dieusys(LOG_EXIT_SYS, "copy: ", src.s," to: ", dst.s) ;
     }
 
     log_info("Successfully restored snapshot: ", snapname) ;