lib-index: Improve error messages when transaction log is unexpectedly lost

diff --git a/src/lib-index/mail-index-map-read.c b/src/lib-index/mail-index-map-read.c
index e84c4b70c8d34ea7ef44a6f6c652276ee0121324..21d0b6ee794975644f6825987715d3a888297fdf 100644 (file)
--- a/src/lib-index/mail-index-map-read.c
+++ b/src/lib-index/mail-index-map-read.c
@@ -296,7 +296,8 @@ static int mail_index_read_map(struct mail_index_map *map, uoff_t file_size)
 
 /* returns -1 = error, 0 = index files are unusable,
    1 = index files are usable or at least repairable */
-static int mail_index_map_latest_file(struct mail_index *index)
+static int
+mail_index_map_latest_file(struct mail_index *index, const char **reason_r)
 {
        struct mail_index_map *old_map, *new_map;
        struct stat st;
@@ -305,7 +306,9 @@ static int mail_index_map_latest_file(struct mail_index *index)
        const char *error;
        int ret, try;
 
-       ret = mail_index_reopen_if_changed(index);
+       *reason_r = NULL;
+
+       ret = mail_index_reopen_if_changed(index, reason_r);
        if (ret <= 0) {
                if (ret < 0)
                        return -1;
@@ -361,6 +364,7 @@ static int mail_index_map_latest_file(struct mail_index *index)
                } T_END;
                if (ret != 0 || try == 2) {
                        if (ret < 0) {
+                               *reason_r = "Corrupted index file";
                                unusable = TRUE;
                                ret = 0;
                        }
@@ -391,12 +395,14 @@ static int mail_index_map_latest_file(struct mail_index *index)
 
        mail_index_unmap(&index->map);
        index->map = new_map;
+       *reason_r = "Index mapped";
        return 1;
 }
 
 int mail_index_map(struct mail_index *index,
                   enum mail_index_sync_handler_type type)
 {
+       const char *reason;
        int ret;
 
        i_assert(!index->mapping);
@@ -410,7 +416,7 @@ int mail_index_map(struct mail_index *index,
        if (index->initial_mapped) {
                /* we're not creating/opening the index.
                   sync this as a view from transaction log. */
-               ret = mail_index_sync_map(&index->map, type, FALSE);
+               ret = mail_index_sync_map(&index->map, type, FALSE, "initial mapping");
        } else {
                ret = 0;
        }
@@ -421,7 +427,7 @@ int mail_index_map(struct mail_index *index,
                   logs (which we'll also do even if the reopening succeeds).
                   if index files are unusable (e.g. major version change)
                   don't even try to use the transaction log. */
-               ret = mail_index_map_latest_file(index);
+               ret = mail_index_map_latest_file(index, &reason);
                if (ret > 0) {
                        /* if we're creating the index file, we don't have any
                           logs yet */
@@ -429,7 +435,7 @@ int mail_index_map(struct mail_index *index,
                                /* and update the map with the latest changes
                                   from transaction log */
                                ret = mail_index_sync_map(&index->map, type,
-                                                         TRUE);
+                                                         TRUE, reason);
                        }
                } else if (ret == 0 && !index->readonly) {
                        /* make sure we don't try to open the file again */

diff --git a/src/lib-index/mail-index-private.h b/src/lib-index/mail-index-private.h
index 9b6392726946d8d6105b89334816fad124086f90..4b5ea73d92efbb6a54a6f00b312717dfc3207e75 100644 (file)
--- a/src/lib-index/mail-index-private.h
+++ b/src/lib-index/mail-index-private.h
@@ -257,7 +257,8 @@ int mail_index_create_tmp_file(struct mail_index *index,
 
 int mail_index_try_open_only(struct mail_index *index);
 void mail_index_close_file(struct mail_index *index);
-int mail_index_reopen_if_changed(struct mail_index *index);
+int mail_index_reopen_if_changed(struct mail_index *index,
+                                const char **reason_r);
 /* Update/rewrite the main index file from index->map */
 void mail_index_write(struct mail_index *index, bool want_rotate);
 

diff --git a/src/lib-index/mail-index-sync-private.h b/src/lib-index/mail-index-sync-private.h
index 985c8da2b776766097c1edb901db75456f19c618..0dcec062d49ad58d02cac1e41bdb99d6ed93ce31 100644 (file)
--- a/src/lib-index/mail-index-sync-private.h
+++ b/src/lib-index/mail-index-sync-private.h
@@ -53,7 +53,8 @@ void mail_index_sync_map_init(struct mail_index_sync_map_ctx *sync_map_ctx,
                              enum mail_index_sync_handler_type type);
 void mail_index_sync_map_deinit(struct mail_index_sync_map_ctx *sync_map_ctx);
 int mail_index_sync_map(struct mail_index_map **map,
-                       enum mail_index_sync_handler_type type, bool force);
+                       enum mail_index_sync_handler_type type, bool force,
+                       const char *sync_reason);
 
 int mail_index_sync_record(struct mail_index_sync_map_ctx *ctx,
                           const struct mail_transaction_header *hdr,

diff --git a/src/lib-index/mail-index-sync-update.c b/src/lib-index/mail-index-sync-update.c
index 76cb8514c73e28b9ee62357bd04247834973a003..adaea5b6e550699d10f534370548372da0d09018 100644 (file)
--- a/src/lib-index/mail-index-sync-update.c
+++ b/src/lib-index/mail-index-sync-update.c
@@ -899,7 +899,8 @@ void mail_index_map_check(struct mail_index_map *map)
 #endif
 
 int mail_index_sync_map(struct mail_index_map **_map,
-                       enum mail_index_sync_handler_type type, bool force)
+                       enum mail_index_sync_handler_type type, bool force,
+                       const char *sync_reason)
 {
        struct mail_index_map *map = *_map;
        struct mail_index *index = map->index;
@@ -963,8 +964,10 @@ int mail_index_sync_map(struct mail_index_map **_map,
                if (force && ret == 0) {
                        /* the seq/offset is probably broken */
                        mail_index_set_error(index, "Index %s: Lost log for "
-                               "seq=%u offset=%"PRIuUOFF_T": %s", index->filepath,
-                               map->hdr.log_file_seq, start_offset, reason);
+                               "seq=%u offset=%"PRIuUOFF_T": %s "
+                               "(initial_mapped=%d, reason=%s)", index->filepath,
+                               map->hdr.log_file_seq, start_offset, reason,
+                               index->initial_mapped, sync_reason);
                        (void)mail_index_fsck(index);
                }
                /* can't use it. sync by re-reading index. */

diff --git a/src/lib-index/mail-index.c b/src/lib-index/mail-index.c
index 87c58ff8c362d1fef2aa41d14528f6dc92713b6b..6d4b8d7c4674cb5b467b1cfda9581da84204fe54 100644 (file)
--- a/src/lib-index/mail-index.c
+++ b/src/lib-index/mail-index.c
@@ -689,21 +689,27 @@ int mail_index_unlink(struct mail_index *index)
        }
 }
 
-int mail_index_reopen_if_changed(struct mail_index *index)
+int mail_index_reopen_if_changed(struct mail_index *index,
+                                const char **reason_r)
 {
        struct stat st1, st2;
+       int ret;
 
-       if (MAIL_INDEX_IS_IN_MEMORY(index))
+       if (MAIL_INDEX_IS_IN_MEMORY(index)) {
+               *reason_r = "in-memory index";
                return 0;
+       }
 
        if (index->fd == -1)
-               return mail_index_try_open_only(index);
+               goto final;
 
        if ((index->flags & MAIL_INDEX_OPEN_FLAG_NFS_FLUSH) != 0)
                nfs_flush_file_handle_cache(index->filepath);
        if (nfs_safe_stat(index->filepath, &st2) < 0) {
-               if (errno == ENOENT)
+               if (errno == ENOENT) {
+                       *reason_r = "index not found via stat()";
                        return 0;
+               }
                mail_index_set_syscall_error(index, "stat()");
                return -1;
        }
@@ -714,17 +720,26 @@ int mail_index_reopen_if_changed(struct mail_index *index)
                        return -1;
                }
                /* deleted/recreated, reopen */
+               *reason_r = "index is stale";
        } else if (st1.st_ino == st2.st_ino &&
                   CMP_DEV_T(st1.st_dev, st2.st_dev)) {
                /* the same file */
+               *reason_r = "index unchanged";
                return 1;
+       } else {
+               *reason_r = "index inode changed";
        }
 
        /* new file, new locks. the old fd can keep its locks, they don't
           matter anymore as no-one's going to modify the file. */
        mail_index_close_file(index);
 
-       return mail_index_try_open_only(index);
+final:
+       if ((ret = mail_index_try_open_only(index)) == 0)
+               *reason_r = "index not found via open()";
+       else if (ret > 0)
+               *reason_r = "index opened";
+       return ret;
 }
 
 int mail_index_refresh(struct mail_index *index)

diff --git a/src/lib-index/mail-transaction-log-view.c b/src/lib-index/mail-transaction-log-view.c
index da05361a6a24e90d080c67caed2a55a88ef0d106..fb265059726f1ad1e99d3f306ef279d4a644505b 100644 (file)
--- a/src/lib-index/mail-transaction-log-view.c
+++ b/src/lib-index/mail-transaction-log-view.c
@@ -2,6 +2,7 @@
 
 #include "lib.h"
 #include "array.h"
+#include "str.h"
 #include "mail-index-private.h"
 #include "mail-transaction-log-view-private.h"
 
@@ -58,6 +59,20 @@ void mail_transaction_log_view_close(struct mail_transaction_log_view **_view)
        i_free(view);
 }
 
+static const char *
+mail_transaction_log_get_file_seqs(struct mail_transaction_log *log)
+{
+       struct mail_transaction_log_file *file;
+       string_t *str = t_str_new(32);
+
+       if (log->files == NULL)
+               return "";
+
+       for (file = log->files; file != NULL; file = file->next)
+               str_printfa(str, ",%u", file->hdr.file_seq);
+       return str_c(str) + 1;
+}
+
 int mail_transaction_log_view_set(struct mail_transaction_log_view *view,
                                  uint32_t min_file_seq, uoff_t min_file_offset,
                                  uint32_t max_file_seq, uoff_t max_file_offset,
@@ -176,8 +191,9 @@ int mail_transaction_log_view_set(struct mail_transaction_log_view *view,
                                    file->hdr.file_seq > max_file_seq) {
                                        /* missing files in the middle */
                                        *reason_r = t_strdup_printf(
-                                               "Missing middle file seq=%u (between %u..%u)",
-                                               seq, min_file_seq, max_file_seq);
+                                               "Missing middle file seq=%u (between %u..%u, we have seqs %s)",
+                                               seq, min_file_seq, max_file_seq,
+                                               mail_transaction_log_get_file_seqs(view->log));
                                        return 0;
                                }