From f6c565fc9e6eb64722e975e20afc50bfac43297d Mon Sep 17 00:00:00 2001
From: "Zaiming (Stone) Shi" <zmstone@gmail.com>
Date: Mon, 29 Aug 2022 11:08:10 +0200
Subject: [PATCH] fix(emqx): Check Erlang start after su command

When installed from RPM or DEB, In case EMQX in started by root,
the boot script changes user to emqx and then re-enter with the
same args.
Prior to this change, the Erlang start check is done before
su, causing it to be checked twice.
This commit moves the Erlang start check to after th su
---
 bin/emqx | 86 ++++++++++++++++++++++++++++----------------------------
 1 file changed, 43 insertions(+), 43 deletions(-)

diff --git a/bin/emqx b/bin/emqx
index f129a8447..66696052e 100755
--- a/bin/emqx
+++ b/bin/emqx
@@ -37,49 +37,6 @@ ERTS_LIB_DIR="$ERTS_DIR/../lib"
 # the 'x' attributes may get lost if the files are extracted from a relup package
 find "$BINDIR" -exec chmod a+x {} \;
 
-# Echo to stderr on errors
-echoerr() { echo "$*" 1>&2; }
-
-die() {
-    set +x
-    echoerr "ERROR: $1"
-    errno=${2:-1}
-    exit "$errno"
-}
-
-assert_node_alive() {
-    if ! relx_nodetool "ping" > /dev/null; then
-        die "node_is_not_running!" 1
-    fi
-}
-
-check_erlang_start() {
-    # set ERL_CRASH_DUMP_BYTES to zero so it will not write a crash dump file
-    env ERL_CRASH_DUMP_BYTES=0 "$BINDIR/$PROGNAME" -boot "$REL_DIR/start_clean" -eval "crypto:start(),halt()"
-}
-
-if ! check_erlang_start >/dev/null 2>&1; then
-    BUILT_ON="$(head -1 "${REL_DIR}/BUILT_ON")"
-    ## failed to start, might be due to missing libs, try to be portable
-    export LD_LIBRARY_PATH="$DYNLIBS_DIR:$LD_LIBRARY_PATH"
-    if ! check_erlang_start; then
-        ## it's hopeless
-        echoerr "FATAL: Unable to start Erlang."
-        echoerr "Please make sure openssl-1.1.1 (libcrypto) and libncurses are installed."
-        echoerr "Also ensure it's running on the correct platform,"
-        echoerr "this EMQX release is built for $BUILT_ON"
-        exit 1
-    fi
-    echoerr "There seem to be missing dynamic libs from the OS."
-    echoerr "Using libs from ${DYNLIBS_DIR} instead."
-    echoerr "NOTE: EMQX's rpm or deb package installation is recommended!"
-fi
-
-## backward compatible
-if [ -d "$ERTS_DIR/lib" ]; then
-    export LD_LIBRARY_PATH="$ERTS_DIR/lib:$LD_LIBRARY_PATH"
-fi
-
 # cuttlefish try to read environment variables starting with "EMQX_"
 export CUTTLEFISH_ENV_OVERRIDE_PREFIX='EMQX_'
 
@@ -261,6 +218,49 @@ if [ "$ES" -ne 0 ]; then
     exit $ES
 fi
 
+# Echo to stderr on errors
+echoerr() { echo "$*" 1>&2; }
+
+die() {
+    set +x
+    echoerr "ERROR: $1"
+    errno=${2:-1}
+    exit "$errno"
+}
+
+assert_node_alive() {
+    if ! relx_nodetool "ping" > /dev/null; then
+        die "node_is_not_running!" 1
+    fi
+}
+
+check_erlang_start() {
+    # set ERL_CRASH_DUMP_BYTES to zero so it will not write a crash dump file
+    env ERL_CRASH_DUMP_BYTES=0 "$BINDIR/$PROGNAME" -boot "$REL_DIR/start_clean" -eval "crypto:start(),halt()"
+}
+
+if ! check_erlang_start >/dev/null 2>&1; then
+    BUILT_ON="$(head -1 "${REL_DIR}/BUILT_ON")"
+    ## failed to start, might be due to missing libs, try to be portable
+    export LD_LIBRARY_PATH="$DYNLIBS_DIR:$LD_LIBRARY_PATH"
+    if ! check_erlang_start; then
+        ## it's hopeless
+        echoerr "FATAL: Unable to start Erlang."
+        echoerr "Please make sure openssl-1.1.1 (libcrypto) and libncurses are installed."
+        echoerr "Also ensure it's running on the correct platform,"
+        echoerr "this EMQX release is built for $BUILT_ON"
+        exit 1
+    fi
+    echoerr "There seem to be missing dynamic libs from the OS."
+    echoerr "Using libs from ${DYNLIBS_DIR} instead."
+    echoerr "NOTE: EMQX's rpm or deb package installation is recommended!"
+fi
+
+## backward compatible (old EMQX versions does this)
+if [ -d "$ERTS_DIR/lib" ]; then
+    export LD_LIBRARY_PATH="$ERTS_DIR/lib:$LD_LIBRARY_PATH"
+fi
+
 if [ -z "$WITH_EPMD" ]; then
     EPMD_ARG="-start_epmd false -epmd_module ekka_epmd -proto_dist ekka"
 else