Merge remote-tracking branch 'mdroth/qga-pull-1-8-2013' into staging

* mdroth/qga-pull-1-8-2013:
  qemu-ga: sample fsfreeze hooks
  qemu-ga: execute hook to quiesce the guest on fsfreeze-freeze/thaw
  qemu-ga: guest_suspend(): improve error reporting
  qemu-ga: bios_supports_mode(): improve error reporting
  qemu-ga: qmp_guest_network_get_interfaces(): get rid of snprintf() + error_set()
  qemu-ga: qmp_guest_fstrim(): get rid of sprintf() + error_set()
  qemu-ga: qmp_guest_fsfreeze_*(): get rid of sprintf() + error_set()
  qemu-ga: build_fs_mount_list(): take an Error argument
  qemu-ga: qmp_guest_shutdown(): improve error reporting
  qemu-ga: qmp_guest_file_*: improve error reporting
  qemu-ga: qmp_guest_file_close(): fix fclose() error check
  qemu-ga: guest_file_handle_find(): take an Error argument

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

1 files changed, 56 insertions, 0 deletions

diff --git a/scripts/qemu-guest-agent/fsfreeze-hook.d/mysql-flush.sh.sample b/scripts/qemu-guest-agent/fsfreeze-hook.d/mysql-flush.sh.sample
new file mode 100755
index 0000000000..2b4fa3aeb1
--- /dev/null
+++ b/scripts/qemu-guest-agent/fsfreeze-hook.d/mysql-flush.sh.sample
@@ -0,0 +1,56 @@
+#!/bin/sh
+
+# Flush MySQL tables to the disk before the filesystem is frozen.
+# At the same time, this keeps a read lock in order to avoid write accesses
+# from the other clients until the filesystem is thawed.
+
+MYSQL="/usr/bin/mysql"
+MYSQL_OPTS="-uroot" #"-prootpassword"
+FIFO=/var/run/mysql-flush.fifo
+
+# Check mysql is installed and the server running
+[ -x "$MYSQL" ] && "$MYSQL" $MYSQL_OPTS < /dev/null || exit 0
+
+flush_and_wait() {
+    printf "FLUSH TABLES WITH READ LOCK \\G\n"
+    trap 'printf "$(date): $0 is killed\n">&2' HUP INT QUIT ALRM TERM
+    read < $FIFO
+    printf "UNLOCK TABLES \\G\n"
+    rm -f $FIFO
+}
+
+case "$1" in
+    freeze)
+        mkfifo $FIFO || exit 1
+        flush_and_wait | "$MYSQL" $MYSQL_OPTS &
+        # wait until every block is flushed
+        while [ "$(echo 'SHOW STATUS LIKE "Key_blocks_not_flushed"' |\
+                 "$MYSQL" $MYSQL_OPTS | tail -1 | cut -f 2)" -gt 0 ]; do
+            sleep 1
+        done
+        # for InnoDB, wait until every log is flushed
+        INNODB_STATUS=$(mktemp /tmp/mysql-flush.XXXXXX)
+        [ $? -ne 0 ] && exit 2
+        trap "rm -f $INNODB_STATUS; exit 1" HUP INT QUIT ALRM TERM
+        while :; do
+            printf "SHOW ENGINE INNODB STATUS \\G" |\
+                "$MYSQL" $MYSQL_OPTS > $INNODB_STATUS
+            LOG_CURRENT=$(grep 'Log sequence number' $INNODB_STATUS |\
+                          tr -s ' ' | cut -d' ' -f4)
+            LOG_FLUSHED=$(grep 'Log flushed up to' $INNODB_STATUS |\
+                          tr -s ' ' | cut -d' ' -f5)
+            [ "$LOG_CURRENT" = "$LOG_FLUSHED" ] && break
+            sleep 1
+        done
+        rm -f $INNODB_STATUS
+        ;;
+
+    thaw)
+        [ ! -p $FIFO ] && exit 1
+        echo > $FIFO
+        ;;
+
+    *)
+        exit 1
+        ;;
+esac