sd-journal: merge journal_file_next_entry_for_data() with generic_array_get_plus_one()

Because journal_file_next_entry_for_data() provides the first entry, while
journal_file_next_entry() actually provides the next entry of the input,
this also renames it to journal_file_move_to_entry_for_data().

Also, previously, on DIRECTION_UP the function did not fall back to the
'extra' entry when all entries linked in the chained array are broken.
This also fixes the issue, and now it fall back to the extra entry.

diff --git a/src/journal/test-journal.c b/src/journal/test-journal.c
index cd295b2a7e51bc751a6e37283788729e0b7588ab..b227b9be6cd3214397a9763ddafd28d22adae6dc 100644 (file)
--- a/src/journal/test-journal.c
+++ b/src/journal/test-journal.c
@@ -74,17 +74,17 @@ static void test_non_empty_one(void) {
         assert_se(le64toh(o->entry.seqnum) == 1);
 
         assert_se(journal_file_find_data_object(f->file, test, strlen(test), &d, NULL) == 1);
-        assert_se(journal_file_next_entry_for_data(f->file, d, DIRECTION_DOWN, &o, NULL) == 1);
+        assert_se(journal_file_move_to_entry_for_data(f->file, d, DIRECTION_DOWN, &o, NULL) == 1);
         assert_se(le64toh(o->entry.seqnum) == 1);
 
-        assert_se(journal_file_next_entry_for_data(f->file, d, DIRECTION_UP, &o, NULL) == 1);
+        assert_se(journal_file_move_to_entry_for_data(f->file, d, DIRECTION_UP, &o, NULL) == 1);
         assert_se(le64toh(o->entry.seqnum) == 3);
 
         assert_se(journal_file_find_data_object(f->file, test2, strlen(test2), &d, NULL) == 1);
-        assert_se(journal_file_next_entry_for_data(f->file, d, DIRECTION_UP, &o, NULL) == 1);
+        assert_se(journal_file_move_to_entry_for_data(f->file, d, DIRECTION_UP, &o, NULL) == 1);
         assert_se(le64toh(o->entry.seqnum) == 2);
 
-        assert_se(journal_file_next_entry_for_data(f->file, d, DIRECTION_DOWN, &o, NULL) == 1);
+        assert_se(journal_file_move_to_entry_for_data(f->file, d, DIRECTION_DOWN, &o, NULL) == 1);
         assert_se(le64toh(o->entry.seqnum) == 2);
 
         assert_se(journal_file_find_data_object(f->file, "quux", 4, &d, NULL) == 0);

diff --git a/src/libsystemd/sd-journal/journal-file.c b/src/libsystemd/sd-journal/journal-file.c
index e34ca360d9bb10b73f39b57f123ede84fc0ae657..1b80afe74dcfadb2b2bc6df38ae32710200cd0e1 100644 (file)
--- a/src/libsystemd/sd-journal/journal-file.c
+++ b/src/libsystemd/sd-journal/journal-file.c
@@ -2866,37 +2866,6 @@ static int generic_array_get(
         return 0;
 }
 
-static int generic_array_get_plus_one(
-                JournalFile *f,
-                uint64_t extra,
-                uint64_t first,
-                uint64_t i,
-                direction_t direction,
-                Object **ret_object,
-                uint64_t *ret_offset) {
-
-        int r;
-
-        assert(f);
-
-        /* FIXME: fix return value assignment on success. */
-
-        if (i == 0) {
-                r = journal_file_move_to_object(f, OBJECT_ENTRY, extra, ret_object);
-                if (IN_SET(r, -EADDRNOTAVAIL, -EBADMSG))
-                        return generic_array_get(f, first, 0, direction, ret_object, ret_offset);
-                if (r < 0)
-                        return r;
-
-                if (ret_offset)
-                        *ret_offset = extra;
-
-                return 1;
-        }
-
-        return generic_array_get(f, first, i - 1, direction, ret_object, ret_offset);
-}
-
 enum {
         TEST_FOUND,
         TEST_LEFT,
@@ -3470,39 +3439,67 @@ int journal_file_next_entry(
         return 1;
 }
 
-int journal_file_next_entry_for_data(
+int journal_file_move_to_entry_for_data(
                 JournalFile *f,
                 Object *d,
                 direction_t direction,
                 Object **ret_object,
                 uint64_t *ret_offset) {
 
-        uint64_t i, n, ofs;
-        int r;
+        uint64_t extra, first, n;
+        int r = 0;
 
         assert(f);
         assert(d);
         assert(d->object.type == OBJECT_DATA);
+        assert(IN_SET(direction, DIRECTION_DOWN, DIRECTION_UP));
 
         /* FIXME: fix return value assignment. */
 
-        n = le64toh(READ_NOW(d->data.n_entries));
+        /* This returns the first (when the direction is down, otherwise the last) entry linked to the
+         * specified data object. */
+
+        n = le64toh(d->data.n_entries);
         if (n <= 0)
-                return n;
+                return 0;
+        n--; /* n_entries is the number of entries linked to the data object, including the 'extra' entry. */
 
-        i = direction == DIRECTION_DOWN ? 0 : n - 1;
+        extra = le64toh(d->data.entry_offset);
+        first = le64toh(d->data.entry_array_offset);
 
-        r = generic_array_get_plus_one(f,
-                                       le64toh(d->data.entry_offset),
-                                       le64toh(d->data.entry_array_offset),
-                                       i,
-                                       direction,
-                                       ret_object, &ofs);
-        if (r <= 0)
-                return r;
+        if (direction == DIRECTION_DOWN && extra > 0) {
+                /* When we are going downwards, first try to read the extra entry. */
+                r = journal_file_move_to_object(f, OBJECT_ENTRY, extra, ret_object);
+                if (r >= 0)
+                        goto use_extra;
+                if (!IN_SET(r, -EADDRNOTAVAIL, -EBADMSG))
+                        return r;
+        }
 
+        if (n > 0) {
+                /* DIRECTION_DOWN : The extra entry is broken, falling back to the entries in the array.
+                 * DIRECTION_UP   : Try to find a valid entry in the array from the tail. */
+                r = generic_array_get(f,
+                                      first,
+                                      direction == DIRECTION_DOWN ? 0 : n - 1,
+                                      direction,
+                                      ret_object, ret_offset);
+                if (!IN_SET(r, 0, -EADDRNOTAVAIL, -EBADMSG))
+                        return r; /* found or critical error. */
+        }
+
+        if (direction == DIRECTION_UP && extra > 0) {
+                /* No valid entry exists in the chained array, falling back to the extra entry. */
+                r = journal_file_move_to_object(f, OBJECT_ENTRY, extra, ret_object);
+                if (r >= 0)
+                        goto use_extra;
+        }
+
+        return r;
+
+use_extra:
         if (ret_offset)
-                *ret_offset = ofs;
+                *ret_offset = extra;
 
         return 1;
 }
@@ -4464,12 +4461,7 @@ int journal_file_get_cutoff_monotonic_usec(JournalFile *f, sd_id128_t boot_id, u
                 if (r < 0)
                         return r;
 
-                r = generic_array_get_plus_one(f,
-                                               le64toh(o->data.entry_offset),
-                                               le64toh(o->data.entry_array_offset),
-                                               le64toh(o->data.n_entries) - 1,
-                                               DIRECTION_UP,
-                                               &o, NULL);
+                r = journal_file_move_to_entry_for_data(f, o, DIRECTION_UP, &o, NULL);
                 if (r <= 0)
                         return r;
 

diff --git a/src/libsystemd/sd-journal/journal-file.h b/src/libsystemd/sd-journal/journal-file.h
index b018fd8788e056d9953c30060f9caec831ee6625..6c46dff4c45cfe3381dc5a27189898b4f39720e5 100644 (file)
--- a/src/libsystemd/sd-journal/journal-file.h
+++ b/src/libsystemd/sd-journal/journal-file.h
@@ -286,13 +286,13 @@ void journal_file_reset_location(JournalFile *f);
 void journal_file_save_location(JournalFile *f, Object *o, uint64_t offset);
 int journal_file_next_entry(JournalFile *f, uint64_t p, direction_t direction, Object **ret_object, uint64_t *ret_offset);
 
-int journal_file_next_entry_for_data(JournalFile *f, Object *d, direction_t direction, Object **ret_object, uint64_t *ret_offset);
-
 int journal_file_move_to_entry_by_offset(JournalFile *f, uint64_t p, direction_t direction, Object **ret_object, uint64_t *ret_offset);
 int journal_file_move_to_entry_by_seqnum(JournalFile *f, uint64_t seqnum, direction_t direction, Object **ret_object, uint64_t *ret_offset);
 int journal_file_move_to_entry_by_realtime(JournalFile *f, uint64_t realtime, direction_t direction, Object **ret_object, uint64_t *ret_offset);
 int journal_file_move_to_entry_by_monotonic(JournalFile *f, sd_id128_t boot_id, uint64_t monotonic, direction_t direction, Object **ret_object, uint64_t *ret_offset);
 
+int journal_file_move_to_entry_for_data(JournalFile *f, Object *d, direction_t direction, Object **ret_object, uint64_t *ret_offset);
+
 int journal_file_move_to_entry_by_offset_for_data(JournalFile *f, Object *d, uint64_t p, direction_t direction, Object **ret_object, uint64_t *ret_offset);
 int journal_file_move_to_entry_by_seqnum_for_data(JournalFile *f, Object *d, uint64_t seqnum, direction_t direction, Object **ret_object, uint64_t *ret_offset);
 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);

diff --git a/src/libsystemd/sd-journal/sd-journal.c b/src/libsystemd/sd-journal/sd-journal.c
index 1b9dcbdecb30acd148e11487d1a8ef23023c420a..3b8ca21725c1120d2c4e2e2da6e896c3f61b603c 100644 (file)
--- a/src/libsystemd/sd-journal/sd-journal.c
+++ b/src/libsystemd/sd-journal/sd-journal.c
@@ -660,9 +660,9 @@ static int find_location_for_match(
                 /* FIXME: missing: find by monotonic */
 
                 if (j->current_location.type == LOCATION_HEAD)
-                        return direction == DIRECTION_DOWN ? journal_file_next_entry_for_data(f, d, DIRECTION_DOWN, ret, offset) : 0;
+                        return direction == DIRECTION_DOWN ? journal_file_move_to_entry_for_data(f, d, DIRECTION_DOWN, ret, offset) : 0;
                 if (j->current_location.type == LOCATION_TAIL)
-                        return direction == DIRECTION_UP ? journal_file_next_entry_for_data(f, d, DIRECTION_UP, ret, offset) : 0;
+                        return direction == DIRECTION_UP ? journal_file_move_to_entry_for_data(f, d, DIRECTION_UP, ret, offset) : 0;
                 if (j->current_location.seqnum_set && sd_id128_equal(j->current_location.seqnum_id, f->header->seqnum_id))
                         return journal_file_move_to_entry_by_seqnum_for_data(f, d, j->current_location.seqnum, direction, ret, offset);
                 if (j->current_location.monotonic_set) {
@@ -678,7 +678,7 @@ static int find_location_for_match(
                 if (j->current_location.realtime_set)
                         return journal_file_move_to_entry_by_realtime_for_data(f, d, j->current_location.realtime, direction, ret, offset);
 
-                return journal_file_next_entry_for_data(f, d, direction, ret, offset);
+                return journal_file_move_to_entry_for_data(f, d, direction, ret, offset);
 
         } else if (m->type == MATCH_OR_TERM) {
                 uint64_t np = 0;