- Added rr trace and renamed mysqld to mariadb client

Author: Thirunarayanan

scripts/mariabackup/mariabackup.sh

@@ -1,9 +1,23 @@
 #!/bin/sh
 me=${0##*/}
 die() {
+    echo "$me: $*" >&2
     exit 1
 }
 
+#   MARIABACKUP_RR=1 (wrap with "rr record")
+#   MARIABACKUP_RR="rr record -h" (use a custom recorder command)
+
+rr=
+case ${MARIABACKUP_RR:-} in
+    ''|0|no) ;;
+    1|yes)   rr="rr record" ;;
+    *)       rr=$MARIABACKUP_RR ;;
+esac
+# Where "rr record" stores traces, so we can point at it on a crash.
+rr_trace_dir=${_RR_TRACE_DIR:-${XDG_DATA_HOME:-$HOME/.local/share}/rr}
+
+
 MODE=
 TARGET_DIR=
 DATADIR=
@@ -76,7 +90,7 @@ done
 
 [ -n "$TARGET_DIR" ] || die "--target-dir required"
 
-# Run mysql with the connection options we collected.
+# Run the client with the connection options we collected.
 ask() { mariadb $MARIADB_OPTS -BN -e "$1" 2>/dev/null; }
 
 
@@ -90,8 +104,13 @@ if [ "$MODE" = prepare ]; then
     [ -f "$cnf" ] || die "$cnf missing - was this backup made by the wrapper?"
     [ -z "$EXPORT" ] || echo "$me: --export not implemented, doing a plain recovery" >&2
 
-    mysqld=$(sed -n 's/^# *mysqld=//p' "$cnf" | tail -n1)
-    [ -n "$mysqld" ] || mysqld=mariadbd
+    # Prefer mariadbd on PATH; fall back to the path recorded at backup time.
+    if command -v mariadbd >/dev/null 2>&1; then
+        mariadbd=mariadbd
+    else
+        mariadbd=$(sed -n 's/^# *mariadbd=//p' "$cnf" | tail -n1)
+        [ -n "$mariadbd" ] || mariadbd=mariadbd
+    fi
 
     # backup.cnf tells us the LSN window recovery should replay.
     start=$(grep  '^innodb_log_recovery_start'  "$TARGET_DIR/backup.cnf" | cut -d= -f2 | tr -d ' ')
@@ -125,10 +144,14 @@ select concat(@header,@checkpoint,@payload) into dumpfile '$newlog';
 EOF
     fi
 
-    $mysqld --defaults-file="$cnf" $opts --bootstrap < "$input"
+    $rr $mariadbd --defaults-file="$cnf" $opts --bootstrap < "$input"
     rc=$?
     [ "$input" = /dev/null ] || rm -f "$input"
-    [ $rc -eq 0 ] || die "recovery failed (mariadbd exited $rc)"
+    if [ $rc -ne 0 ]; then
+        [ -z "$rr" ] || echo "$me: rr trace: $rr_trace_dir/latest-trace" \
+            "(replay with: rr replay $rr_trace_dir/latest-trace)" >&2
+        die "recovery failed (mariadbd exited $rc)"
+    fi
 
     if [ -n "$target" ]; then
         [ -f "$newlog" ] || die "could not build ib_logfile0 for LSN $target"
@@ -187,22 +210,22 @@ case $PARALLEL in           # --parallel=N -> "N CONCURRENT" (1 is the default)
 esac
 mariadb $MARIADB_OPTS -e "$sql" || die "BACKUP SERVER failed"
 
-# Leave behind backup-prepare.cnf with everything --prepare's offline
-# bootstrap needs: where mariadbd is, the InnoDB geometry, and (if the
-# server is encrypted) how to load the key plugin again.
+# Create backup-prepare.cnf with everything --prepare's offline
+# bootstrap needs: where mariadbd is, the InnoDB parameters,
+# and how to load the key plugin again.
 [ -f "$TARGET_DIR/backup.cnf" ] || exit 0
 
-mysqld=
+mariadbd=
 pidfile=$(ask "SELECT @@global.pid_file")
 if [ -n "$pidfile" ] && [ -r "$pidfile" ]; then
     pid=$(cat "$pidfile" 2>/dev/null)
-    [ -n "$pid" ] && mysqld=$(readlink -f "/proc/$pid/exe" 2>/dev/null)
+    [ -n "$pid" ] && mariadbd=$(readlink -f "/proc/$pid/exe" 2>/dev/null)
 fi
-if [ -z "$mysqld" ]; then
+if [ -z "$mariadbd" ]; then
     basedir=$(ask "SELECT @@global.basedir")
     for c in "$basedir/sbin/mariadbd" "$basedir/bin/mariadbd" \
              "$basedir/sbin/mysqld"   "$basedir/bin/mysqld"; do
-        [ -x "$c" ] && { mysqld=$c; break; }
+        [ -x "$c" ] && { mariadbd=$c; break; }
     done
 fi
 
@@ -217,7 +240,7 @@ enc=$(ask "SELECT LOWER(plugin_name) FROM information_schema.PLUGINS
 
 echo "$me: writing backup-prepare.cnf" >&2
 {
-    [ -n "$mysqld" ] && echo "# mysqld=$mysqld"
+    [ -n "$mariadbd" ] && echo "# mariadbd=$mariadbd"
     echo "[mariadbd]"
     [ -n "$page_size" ]      && echo "innodb_page_size=$page_size"
     [ -n "$data_file_path" ] && echo "innodb_data_file_path=$data_file_path"