core: loopback - simplify check_loopback()

[elogind.git] / src / journal / journal-file.c

diff --git a/src/journal/journal-file.c b/src/journal/journal-file.c
index 8cbdbb9f9634557119011ec7c4ba1057c094ad43..48c27ee627a503f169697e2bb4f967eeb6e9de62 100644 (file)
--- a/src/journal/journal-file.c
+++ b/src/journal/journal-file.c
@@ -26,7 +26,6 @@
 #include <sys/statvfs.h>
 #include <fcntl.h>
 #include <stddef.h>
-#include <sys/xattr.h>
 
 #include "journal-def.h"
 #include "journal-file.h"
@@ -1929,12 +1928,81 @@ int journal_file_move_to_entry_by_monotonic(
 }
 
 void journal_file_reset_location(JournalFile *f) {
+        f->location_type = LOCATION_HEAD;
         f->current_offset = 0;
+        f->current_seqnum = 0;
+        f->current_realtime = 0;
+        f->current_monotonic = 0;
+        zero(f->current_boot_id);
+        f->current_xor_hash = 0;
+}
+
+void journal_file_save_location(JournalFile *f, direction_t direction, Object *o, uint64_t offset) {
+        f->last_direction = direction;
+        f->location_type = LOCATION_SEEK;
+        f->current_offset = offset;
+        f->current_seqnum = le64toh(o->entry.seqnum);
+        f->current_realtime = le64toh(o->entry.realtime);
+        f->current_monotonic = le64toh(o->entry.monotonic);
+        f->current_boot_id = o->entry.boot_id;
+        f->current_xor_hash = le64toh(o->entry.xor_hash);
+}
+
+int journal_file_compare_locations(JournalFile *af, JournalFile *bf) {
+        assert(af);
+        assert(bf);
+        assert(af->location_type == LOCATION_SEEK);
+        assert(bf->location_type == LOCATION_SEEK);
+
+        /* If contents and timestamps match, these entries are
+         * identical, even if the seqnum does not match */
+        if (sd_id128_equal(af->current_boot_id, bf->current_boot_id) &&
+            af->current_monotonic == bf->current_monotonic &&
+            af->current_realtime == bf->current_realtime &&
+            af->current_xor_hash == bf->current_xor_hash)
+                return 0;
+
+        if (sd_id128_equal(af->header->seqnum_id, bf->header->seqnum_id)) {
+
+                /* If this is from the same seqnum source, compare
+                 * seqnums */
+                if (af->current_seqnum < bf->current_seqnum)
+                        return -1;
+                if (af->current_seqnum > bf->current_seqnum)
+                        return 1;
+
+                /* Wow! This is weird, different data but the same
+                 * seqnums? Something is borked, but let's make the
+                 * best of it and compare by time. */
+        }
+
+        if (sd_id128_equal(af->current_boot_id, bf->current_boot_id)) {
+
+                /* If the boot id matches, compare monotonic time */
+                if (af->current_monotonic < bf->current_monotonic)
+                        return -1;
+                if (af->current_monotonic > bf->current_monotonic)
+                        return 1;
+        }
+
+        /* Otherwise, compare UTC time */
+        if (af->current_realtime < bf->current_realtime)
+                return -1;
+        if (af->current_realtime > bf->current_realtime)
+                return 1;
+
+        /* Finally, compare by contents */
+        if (af->current_xor_hash < bf->current_xor_hash)
+                return -1;
+        if (af->current_xor_hash > bf->current_xor_hash)
+                return 1;
+
+        return 0;
 }
 
 int journal_file_next_entry(
                 JournalFile *f,
-                Object *o, uint64_t p,
+                uint64_t p,
                 direction_t direction,
                 Object **ret, uint64_t *offset) {
 
@@ -1942,18 +2010,14 @@ int journal_file_next_entry(
         int r;
 
         assert(f);
-        assert(p > 0 || !o);
 
         n = le64toh(f->header->n_entries);
         if (n <= 0)
                 return 0;
 
-        if (!o)
+        if (p == 0)
                 i = direction == DIRECTION_DOWN ? 0 : n - 1;
         else {
-                if (o->object.type != OBJECT_ENTRY)
-                        return -EINVAL;
-
                 r = generic_array_bisect(f,
                                          le64toh(f->header->entry_array_offset),
                                          le64toh(f->header->n_entries),
@@ -2461,8 +2525,6 @@ int journal_file_open(
         }
 
         if (f->last_stat.st_size == 0 && f->writable) {
-                uint64_t crtime;
-
                 /* Let's attach the creation time to the journal file,
                  * so that the vacuuming code knows the age of this
                  * file even if the file might end up corrupted one
@@ -2473,8 +2535,7 @@ int journal_file_open(
                  * attributes are not supported we'll just skip this,
                  * and rely solely on mtime/atime/ctime of the file. */
 
-                crtime = htole64((uint64_t) now(CLOCK_REALTIME));
-                fsetxattr(f->fd, "user.crtime_usec", &crtime, sizeof(crtime), XATTR_CREATE);
+                fd_setcrtime(f->fd, now(CLOCK_REALTIME));
 
 #ifdef HAVE_GCRYPT
                 /* Try to load the FSPRG state, and if we can't, then