MDEV-28583: Galera: binlogs disappear after rsync IST

This commit sends a flag indicating the presence of the "--bypass"
option from the donor node to the joiner nodes during rsync IST,
because without such a flag it is impossible to distinguish IST
from the SST on the joiner nodes (in IST/SST scripts, because the
"--bypass" option is still not passed to scripts from server code).
Specifically, this fixes an issue with binary logs disappearing
after IST (via rsync). There are also changes to diagnostic messages
here that will make it easier to diagnose script-related problems
in the future when debugging and when checking the logs. This commit
also adds more robust signal handlers - to handle exceptions during
script execution. These handlers won't mask some crashes and it
also unifies exit codes between different scripts. These changes
have already been helpful to debugging "bypass" flag handling.

scripts/wsrep_sst_common.sh

@@ -17,7 +17,8 @@
 
 # This is a common command line parser to be sourced by other SST scripts
 
-set -ue
+trap 'exit 32' HUP PIPE
+trap 'exit 3'  INT QUIT TERM
 
 # Setting the path for some utilities on CentOS
 export PATH="$PATH:/usr/sbin:/usr/bin:/sbin:/bin"
@@ -184,7 +185,7 @@ case "$1" in
         shift
         ;;
     '--bypass')
-        WSREP_SST_OPT_BYPASS=1
+        readonly WSREP_SST_OPT_BYPASS=1
         ;;
     '--datadir')
         # Let's remove the trailing slash:
@@ -511,7 +512,24 @@ case "$1" in
 esac
 shift
 done
-readonly WSREP_SST_OPT_BYPASS
+
+WSREP_TRANSFER_TYPE='SST'
+[ $WSREP_SST_OPT_BYPASS -ne 0 ] && readonly WSREP_TRANSFER_TYPE='IST'
+# Let's take the name of the current script as a base,
+# removing the directory, extension and "wsrep_sst_" prefix:
+WSREP_METHOD="${0##*/}"
+WSREP_METHOD="${WSREP_METHOD%.*}"
+readonly WSREP_METHOD="${WSREP_METHOD#wsrep_sst_}"
+if [ -n "${WSREP_SST_OPT_ROLE+x}" ]; then
+    if [ "$WSREP_SST_OPT_ROLE" != 'donor' -a \
+         "$WSREP_SST_OPT_ROLE" != 'joiner' ]
+    then
+        wsrep_log_error "Unrecognized role: '$WSREP_SST_OPT_ROLE'"
+        exit 22 # EINVAL
+    fi
+else
+    readonly WSREP_SST_OPT_ROLE='donor'
+fi
 
 # The same argument can be present on the command line several
 # times, in this case we must take its last value:
@@ -719,7 +737,7 @@ wsrep_log()
 {
     # echo everything to stderr so that it gets into common error log
     # deliberately made to look different from the rest of the log
-    local readonly tst="$(date +%Y%m%d\ %H:%M:%S.%N | cut -b -21)"
+    local readonly tst=$(date "+%Y%m%d %H:%M:%S.%N" | cut -b -21)
     echo "WSREP_SST: $* ($tst)" >&2
 }
 
@@ -1050,7 +1068,7 @@ is_local_ip()
     [ "$1" = '127.0.0.1' -o \
       "$1" = '127.0.0.2' -o \
       "$1" = 'localhost' -o \
-      "$1" = '[::1]' ] && return 0
+      "$1" = '::1' ] && return 0
     # If the address starts with "127." this is probably a local
     # address, but we need to clarify what follows this prefix:
     if [ "${1#127.}" != "$1" ]; then
@@ -1067,21 +1085,25 @@ is_local_ip()
          "$1" = "$(hostname -f)" -o \
          "$1" = "$(hostname -d)" ] && return 0
     fi
+    # If the address contains anything other than digits
+    # and separators, it is not a local address:
+    [ "${1#*[!0-9.]}" != "$1" ] && \
+    [ "${1#*[!0-9A-Fa-f:\[\]]}" != "$1" ] && return 1
     # Now let's check if the given address is assigned to
     # one of the network cards:
     local ip_util=$(commandex 'ip')
     if [ -n "$ip_util" ]; then
         # ip address show ouput format is " inet[6] <address>/<mask>":
         "$ip_util" address show \
-             | grep -E '^[[:space:]]*inet.? [^[:space:]]+/' -o \
-             | grep -F " $1/" >/dev/null && return 0
+            | grep -o -E '^[[:space:]]*inet.?[[:space:]]+[^[:space:]]+/' \
+            | grep -qw -F -- "$1/" && return 0
     else
         local ifconfig_util=$(commandex 'ifconfig')
         if [ -n "$ifconfig_util" ]; then
             # ifconfig output format is " inet[6] <address> ...":
             "$ifconfig_util" \
-                 | grep -E '^[[:space:]]*inet.? [^[:space:]]+ ' -o \
-                 | grep -F " $1 " >/dev/null && return 0
+                | grep -o -E '^[[:space:]]*inet.?[[:space:]]+[^[:space:]]+' \
+                | grep -qw -F -- "$1" && return 0
         fi
     fi
     return 1
@@ -1403,7 +1425,7 @@ get_proc()
     if [ -z "$nproc" ]; then
         set +e
         if [ "$OS" = 'Linux' ]; then
-            nproc=$(grep -c processor /proc/cpuinfo 2>/dev/null)
+            nproc=$(grep -cw -E '^processor' /proc/cpuinfo 2>/dev/null)
         elif [ "$OS" = 'Darwin' -o "$OS" = 'FreeBSD' ]; then
             nproc=$(sysctl -n hw.ncpu)
         fi
@@ -1452,3 +1474,19 @@ check_server_ssl_config()
         fi
     fi
 }
+
+simple_cleanup()
+{
+    # Since this is invoked just after exit NNN
+    local estatus=$?
+    if [ $estatus -ne 0 ]; then
+        wsrep_log_error "Cleanup after exit with status: $estatus"
+    fi
+    if [ -n "${SST_PID:-}" ]; then
+        [ "$(pwd)" != "$OLD_PWD" ] && cd "$OLD_PWD"
+        [ -f "$SST_PID" ] && rm -f "$SST_PID" || :
+    fi
+    exit $estatus
+}
+
+wsrep_log_info "$WSREP_METHOD $WSREP_TRANSFER_TYPE started on $WSREP_SST_OPT_ROLE"