Then rename(2) is guaranteed to succeed

As we don't support Windows anymore, we can rely on the fact that rename
on POSIX guarantees that the newpath will be atomically replaced.

diff --git a/lib/dns/journal.c b/lib/dns/journal.c
index b6f4d1901bd349acf93706984b93aa6cd50bf2e3..cd99afdcb492e550a9cdf8d260689ffe7ec5b02c 100644 (file)
--- a/lib/dns/journal.c
+++ b/lib/dns/journal.c
@@ -2488,8 +2488,6 @@ dns_journal_compact(isc_mem_t *mctx, char *filename, uint32_t serial,
        isc_result_t result;
        unsigned int indexend;
        char newname[PATH_MAX];
-       char backup[PATH_MAX];
-       bool is_backup = false;
        bool rewrite = false;
        bool downgrade = false;
 
@@ -2504,15 +2502,7 @@ dns_journal_compact(isc_mem_t *mctx, char *filename, uint32_t serial,
                          filename);
        RUNTIME_CHECK(result < sizeof(newname));
 
-       result = snprintf(backup, sizeof(backup), "%.*s.jbk", (int)namelen,
-                         filename);
-       RUNTIME_CHECK(result < sizeof(backup));
-
        result = journal_open(mctx, filename, false, false, false, &j1);
-       if (result == ISC_R_NOTFOUND) {
-               is_backup = true;
-               result = journal_open(mctx, backup, false, false, false, &j1);
-       }
        if (result != ISC_R_SUCCESS) {
                return result;
        }
@@ -2797,36 +2787,13 @@ dns_journal_compact(isc_mem_t *mctx, char *filename, uint32_t serial,
        dns_journal_destroy(&j2);
 
        /*
-        * With a UFS file system this should just succeed and be atomic.
+        * With a POSIX file system this should just succeed and be atomic.
         * Any IXFR outs will just continue and the old journal will be
         * removed on final close.
-        *
-        * With MSDOS / NTFS we need to do a two stage rename, triggered
-        * by EEXIST.  (If any IXFR's are running in other threads, however,
-        * this will fail, and the journal will not be compacted.  But
-        * if so, hopefully they'll be finished by the next time we
-        * compact.)
         */
        if (rename(newname, filename) == -1) {
-               if (errno == EEXIST && !is_backup) {
-                       result = isc_file_remove(backup);
-                       if (result != ISC_R_SUCCESS &&
-                           result != ISC_R_FILENOTFOUND)
-                       {
-                               goto failure;
-                       }
-                       if (rename(filename, backup) == -1) {
-                               goto maperrno;
-                       }
-                       if (rename(newname, filename) == -1) {
-                               goto maperrno;
-                       }
-                       (void)isc_file_remove(backup);
-               } else {
-               maperrno:
-                       result = ISC_R_FAILURE;
-                       goto failure;
-               }
+               result = ISC_R_FAILURE;
+               goto failure;
        }
 
        result = ISC_R_SUCCESS;