[PATCH cluster 04/21] pmxcfs: add ability to query backup progress

[Shannon Sterz <s.sterz@proxmox.com>]

cfs_live_backup_database() will now also return the progress of the
backup instead of just the filename.

Signed-off-by: Shannon Sterz <s.sterz@proxmox.com>
---
 src/PVE/Cluster.pm       | 43 +++++++++++++++++++++++++++++++++++-----
 src/pmxcfs/cfs-ipc-ops.h |  2 ++
 src/pmxcfs/database.c    | 18 +++++++++++++++++
 src/pmxcfs/memdb.c       | 12 +++++++++++
 src/pmxcfs/memdb.h       | 28 ++++++++++++++++++++++++++
 src/pmxcfs/server.c      | 11 ++++++++++
 src/pmxcfs/status.c      |  7 +++++++
 src/pmxcfs/status.h      |  2 ++
 8 files changed, 118 insertions(+), 5 deletions(-)

diff --git a/src/PVE/Cluster.pm b/src/PVE/Cluster.pm
index 31c06e8..b907f2e 100644
--- a/src/PVE/Cluster.pm
+++ b/src/PVE/Cluster.pm
@@ -243,8 +243,14 @@ my $ipcc_init_backup = sub {
     my ($filename) = @_;
 
     my $bindata = pack "Z*", $filename;
-    PVE::IPCC::ipcc_send_rec(CFS_IPC_INIT_BACKUP, $bindata);
-    warn $! if $! != 0;
+    my $result = &$ipcc_send_rec_json(CFS_IPC_INIT_BACKUP, $bindata);
+    die $! if $! != 0;
+
+    return $result;
+};
+
+my $ipcc_backup_progress = sub {
+    return &$ipcc_send_rec_json(CFS_IPC_BACKUP_PROGRESS);
 };
 
 my $ccache = {};
@@ -943,7 +949,11 @@ sub cfs_rename_db_unsafe {
 
 Creates a new live backup of the database backing the cluster file system.
 
-Returns a file path to the created backup.
+Returns a hash with two members: C<file> is the filename of the new backups and
+C<progress> which is also a hash. C<progress> has three members: C<in-progress>,
+a boolean indicating whether the backup is finished or still on-going,
+C<remaining>, an integer showing the pages that are not yet backed up, and
+C<total> showing the total page count.
 
 =cut
 
@@ -964,12 +974,35 @@ sub cfs_live_backup_database {
     my $ctime = time();
     my $backup_file = "config-backup-$ctime.db";
     print "starting backup of current database to \"$dbbackupdir/$backup_file\"\n";
+    my $result = {};
 
-    eval { &$ipcc_init_backup($backup_file); };
+    eval { $result = &$ipcc_init_backup($backup_file); };
+    die $@ if $@;
 
+    return {
+        'file' => $backup_file,
+        'progress' => $result,
+    };
+}
+
+=head3 cfs_live_backup_progress()
+
+Returns a hash that describes the current live backup status of the database
+backing the cluster file system.
+
+It contains three members: C<in-progress>, a boolean indicating whether the
+backup is finished or still on-going, C<remaining>, an integer showing the pages
+that are not yet backed up, and C<total> showing the total page count.
+
+=cut
+
+sub cfs_live_backup_progress {
+    my $result = {};
+
+    eval { $result = &$ipcc_backup_progress(); };
     warn $@ if $@;
 
-    return $backup_file;
+    return $result;
 }
 
 1;
diff --git a/src/pmxcfs/cfs-ipc-ops.h b/src/pmxcfs/cfs-ipc-ops.h
index 054ebb3..e8f7541 100644
--- a/src/pmxcfs/cfs-ipc-ops.h
+++ b/src/pmxcfs/cfs-ipc-ops.h
@@ -47,4 +47,6 @@
 
 #define CFS_IPC_INIT_BACKUP 14
 
+#define CFS_IPC_BACKUP_PROGRESS 15
+
 #endif
diff --git a/src/pmxcfs/database.c b/src/pmxcfs/database.c
index 07b3664..39bdf61 100644
--- a/src/pmxcfs/database.c
+++ b/src/pmxcfs/database.c
@@ -866,3 +866,21 @@ int bdb_handle_backup(db_backend_t *bdb) {
 
     return to_return_code;
 }
+
+memdb_backup_progress_t bdb_backup_progress(db_backend_t *bdb) {
+    memdb_backup_progress_t to_return = {
+        .in_progress = FALSE,
+        .remaining = 0,
+        .total = 0,
+    };
+
+    if (bdb == NULL || bdb->current_backup == NULL) {
+        return to_return;
+    }
+
+    to_return.in_progress = TRUE;
+    to_return.remaining = sqlite3_backup_remaining(bdb->current_backup);
+    to_return.total = sqlite3_backup_pagecount(bdb->current_backup);
+
+    return to_return;
+}
diff --git a/src/pmxcfs/memdb.c b/src/pmxcfs/memdb.c
index b7372f9..255c03f 100644
--- a/src/pmxcfs/memdb.c
+++ b/src/pmxcfs/memdb.c
@@ -1550,3 +1550,15 @@ int memdb_handle_backup(memdb_t *memdb) {
 
     return to_return;
 }
+
+memdb_backup_progress_t memdb_backup_progress(memdb_t *memdb) {
+    memdb_backup_progress_t to_return = {
+        .in_progress = FALSE,
+        .remaining = 0,
+        .total = 0,
+    };
+
+    g_return_val_if_fail(memdb != NULL, to_return);
+
+    return bdb_backup_progress(memdb->bdb);
+}
diff --git a/src/pmxcfs/memdb.h b/src/pmxcfs/memdb.h
index 2c27959..3943328 100644
--- a/src/pmxcfs/memdb.h
+++ b/src/pmxcfs/memdb.h
@@ -88,6 +88,12 @@ typedef struct {
     db_backend_t *bdb;
 } memdb_t;
 
+typedef struct {
+    gboolean in_progress; // whether a backup is currently in progress
+    int remaining;        // how many pages are still remaining to back up
+    int total;            // how many pages there are to back up in total after the last backup step
+} memdb_backup_progress_t;
+
 memdb_t *memdb_open(const char *dbfilename);
 
 void memdb_close(memdb_t *memdb);
@@ -200,6 +206,17 @@ int memdb_finish_or_abort_backup(memdb_t *memdb, gboolean abort);
  */
 int memdb_handle_backup(memdb_t *memdb);
 
+/**
+ * memdb_backup_progress:
+ * @memdb: a memdb object that has an initialized db to back up.
+ *
+ * Queries whether a backup is in progress and if so how far it has progressed.
+ *
+ * Return: the returned `memdb_backup_progress_t` struct provides information on whether a back up
+ * is in progress and if so how far it has progressed.
+ */
+memdb_backup_progress_t memdb_backup_progress(memdb_t *memdb);
+
 db_backend_t *bdb_backend_open(const char *filename, memdb_tree_entry_t *root, GHashTable *index);
 
 void bdb_backend_close(db_backend_t *bdb);
@@ -267,4 +284,15 @@ int bdb_finish_or_abort_backup(db_backend_t *bdb, gboolean abort);
  */
 int bdb_handle_backup(db_backend_t *bdb);
 
+/**
+ * bdb_backup_progress:
+ * @bdb: a db backend that has an initialized db to back up.
+ *
+ * Queries whether a backup is in progress and if so how far it has progressed.
+ *
+ * Return: the returned `memdb_backup_progress_t` struct provides information on whether a back up
+ * is in progress and if so how far it has progressed.
+ */
+memdb_backup_progress_t bdb_backup_progress(db_backend_t *bdb);
+
 #endif /* _PVE_MEMDB_H_ */
diff --git a/src/pmxcfs/server.c b/src/pmxcfs/server.c
index 8149fd3..5f9ab0a 100644
--- a/src/pmxcfs/server.c
+++ b/src/pmxcfs/server.c
@@ -511,6 +511,9 @@ static int32_t s1_msg_process_fn(qb_ipcs_connection_t *c, void *data, size_t siz
                     if (result != 0) {
                         cfs_critical("couldn't add first backup step (error %d), abort...", result);
                         (void)memdb_finish_or_abort_backup(memdb, TRUE);
+                    } else {
+                        memdb_backup_progress_t progress = memdb_backup_progress(memdb);
+                        cfs_create_backup_progress_msg(outbuf, &progress);
                     }
                 }
 
@@ -522,6 +525,14 @@ static int32_t s1_msg_process_fn(qb_ipcs_connection_t *c, void *data, size_t siz
                 result = -EINVAL;
             }
         }
+    } else if (request_id == CFS_IPC_BACKUP_PROGRESS) {
+        if (request_size != sizeof(struct qb_ipc_request_header)) {
+            result = -EINVAL;
+        } else {
+            memdb_backup_progress_t progress = memdb_backup_progress(memdb);
+            cfs_create_backup_progress_msg(outbuf, &progress);
+            result = 0;
+        }
     }
 
     cfs_debug("process result %d", result);
diff --git a/src/pmxcfs/status.c b/src/pmxcfs/status.c
index 9581e2a..41591d5 100644
--- a/src/pmxcfs/status.c
+++ b/src/pmxcfs/status.c
@@ -1974,3 +1974,10 @@ void cfs_set_quorate(uint32_t quorate, gboolean quiet) {
 
     g_mutex_unlock(&mutex);
 }
+
+void cfs_create_backup_progress_msg(GString *str, memdb_backup_progress_t *progress) {
+    g_string_append_printf(
+        str, "{\n\t\"in-progress\": %s,\n\t\"remaining\": %d,\n\t\"total\": %d\n}",
+        progress->in_progress ? "true" : "false", progress->remaining, progress->total
+    );
+}
diff --git a/src/pmxcfs/status.h b/src/pmxcfs/status.h
index 6a6b0a7..0790c88 100644
--- a/src/pmxcfs/status.h
+++ b/src/pmxcfs/status.h
@@ -103,4 +103,6 @@ int cfs_create_guest_conf_properties_msg(
     GString *str, memdb_t *memdb, const char **props, uint8_t num_props, uint32_t vmid
 );
 
+void cfs_create_backup_progress_msg(GString *str, memdb_backup_progress_t *progress);
+
 #endif /* _PVE_STATUS_H_ */
-- 
2.47.3