Merge pull request #26213 from poettering/journal-rework-seqnum

journal sequence number rework

3 files changed, 61 insertions, 5 deletions

diff --git a/src/libsystemd/sd-journal/journal-file.c b/src/libsystemd/sd-journal/journal-file.c
index 2ead29548b..aab33dbfcc 100644
--- a/src/libsystemd/sd-journal/journal-file.c
+++ b/src/libsystemd/sd-journal/journal-file.c
@@ -2094,6 +2094,7 @@ static int journal_file_append_entry_internal(
                 const EntryItem items[],
                 size_t n_items,
                 uint64_t *seqnum,
+                sd_id128_t *seqnum_id,
                 Object **ret_object,
                 uint64_t *ret_offset) {
 
@@ -2139,6 +2140,21 @@ static int journal_file_append_entry_internal(
                 }
         }
 
+        if (seqnum_id) {
+                /* Settle the passed in sequence number ID */
+
+                if (sd_id128_is_null(*seqnum_id))
+                        *seqnum_id = f->header->seqnum_id; /* Caller has none assigned, then copy the one from the file */
+                else if (!sd_id128_equal(*seqnum_id, f->header->seqnum_id)) {
+                        /* Different seqnum IDs? We can't allow entries from multiple IDs end up in the same journal.*/
+                        if (le64toh(f->header->n_entries) == 0)
+                                f->header->seqnum_id = *seqnum_id; /* Caller has one, and file so far has no entries, then copy the one from the caller */
+                        else
+                                return log_debug_errno(SYNTHETIC_ERRNO(EILSEQ),
+                                                       "Sequence number IDs don't match, refusing entry.");
+                }
+        }
+
         osize = offsetof(Object, entry.items) + (n_items * journal_file_entry_item_size(f));
 
         r = journal_file_append_object(f, OBJECT_ENTRY, osize, &o, &np);
@@ -2290,6 +2306,7 @@ int journal_file_append_entry(
                 const struct iovec iovec[],
                 size_t n_iovec,
                 uint64_t *seqnum,
+                sd_id128_t *seqnum_id,
                 Object **ret_object,
                 uint64_t *ret_offset) {
 
@@ -2376,7 +2393,7 @@ int journal_file_append_entry(
         typesafe_qsort(items, n_iovec, entry_item_cmp);
         n_iovec = remove_duplicate_entry_items(items, n_iovec);
 
-        r = journal_file_append_entry_internal(f, ts, boot_id, xor_hash, items, n_iovec, seqnum, ret_object, ret_offset);
+        r = journal_file_append_entry_internal(f, ts, boot_id, xor_hash, items, n_iovec, seqnum, seqnum_id, ret_object, ret_offset);
 
         /* If the memory mapping triggered a SIGBUS then we return an
          * IO error and ignore the error code passed down to us, since
@@ -4093,7 +4110,14 @@ int journal_file_dispose(int dir_fd, const char *fname) {
         return 0;
 }
 
-int journal_file_copy_entry(JournalFile *from, JournalFile *to, Object *o, uint64_t p) {
+int journal_file_copy_entry(
+                JournalFile *from,
+                JournalFile *to,
+                Object *o,
+                uint64_t p,
+                uint64_t *seqnum,
+                sd_id128_t *seqnum_id) {
+
         _cleanup_free_ EntryItem *items_alloc = NULL;
         EntryItem *items;
         uint64_t q, n, xor_hash = 0;
@@ -4168,7 +4192,7 @@ int journal_file_copy_entry(JournalFile *from, JournalFile *to, Object *o, uint6
                         return r;
         }
 
-        r = journal_file_append_entry_internal(to, &ts, boot_id, xor_hash, items, n, NULL, NULL, NULL);
+        r = journal_file_append_entry_internal(to, &ts, boot_id, xor_hash, items, n, seqnum, seqnum_id, NULL, NULL);
 
         if (mmap_cache_fd_got_sigbus(to->cache_fd))
                 return -EIO;
diff --git a/src/libsystemd/sd-journal/journal-file.h b/src/libsystemd/sd-journal/journal-file.h
index 8c809ed4b9..07f1f5d180 100644
--- a/src/libsystemd/sd-journal/journal-file.h
+++ b/src/libsystemd/sd-journal/journal-file.h
@@ -259,7 +259,8 @@ int journal_file_append_entry(
                 const sd_id128_t *boot_id,
                 const struct iovec iovec[],
                 size_t n_iovec,
-                uint64_t *seqno,
+                uint64_t *seqnum,
+                sd_id128_t *seqnum_id,
                 Object **ret_object,
                 uint64_t *ret_offset);
 
@@ -286,7 +287,7 @@ int journal_file_move_to_entry_by_seqnum_for_data(JournalFile *f, Object *d, uin
 int journal_file_move_to_entry_by_realtime_for_data(JournalFile *f, Object *d, uint64_t realtime, direction_t direction, Object **ret_object, uint64_t *ret_offset);
 int journal_file_move_to_entry_by_monotonic_for_data(JournalFile *f, Object *d, sd_id128_t boot_id, uint64_t monotonic, direction_t direction, Object **ret_object, uint64_t *ret_offset);
 
-int journal_file_copy_entry(JournalFile *from, JournalFile *to, Object *o, uint64_t p);
+int journal_file_copy_entry(JournalFile *from, JournalFile *to, Object *o, uint64_t p, uint64_t *seqnum, sd_id128_t *seqnum_id);
 
 void journal_file_dump(JournalFile *f);
 void journal_file_print_header(JournalFile *f);
diff --git a/src/libsystemd/sd-journal/sd-journal.c b/src/libsystemd/sd-journal/sd-journal.c
index 9947947ef2..afbf255266 100644
--- a/src/libsystemd/sd-journal/sd-journal.c
+++ b/src/libsystemd/sd-journal/sd-journal.c
@@ -2232,6 +2232,37 @@ _public_ int sd_journal_get_monotonic_usec(sd_journal *j, uint64_t *ret, sd_id12
         return 0;
 }
 
+_public_ int sd_journal_get_seqnum(
+                sd_journal *j,
+                uint64_t *ret_seqnum,
+                sd_id128_t *ret_seqnum_id) {
+
+        JournalFile *f;
+        Object *o;
+        int r;
+
+        assert_return(j, -EINVAL);
+        assert_return(!journal_pid_changed(j), -ECHILD);
+
+        f = j->current_file;
+        if (!f)
+                return -EADDRNOTAVAIL;
+
+        if (f->current_offset <= 0)
+                return -EADDRNOTAVAIL;
+
+        r = journal_file_move_to_object(f, OBJECT_ENTRY, f->current_offset, &o);
+        if (r < 0)
+                return r;
+
+        if (ret_seqnum_id)
+                *ret_seqnum_id = f->header->seqnum_id;
+        if (ret_seqnum)
+                *ret_seqnum = le64toh(o->entry.seqnum);
+
+        return 0;
+}
+
 static bool field_is_valid(const char *field) {
         assert(field);