[show techsupport] fix bash errors in generate_dump script (#1844)

What I did
Fix: sonic-net/sonic-buildimage#8850

Issue was introduced by #1723, #1833, and #1843 (pending merge)

The error_handler is a great idea but the bash script needs to be error free first.

How I did it
Fix bash script errors.

How to verify it
run show techsupport test..

Signed-off-by: Ying Xie <ying.xie@microsoft.com>

scripts/generate_dump

@@ -193,8 +193,9 @@ save_cmd() {
  if $NOOP; then
  echo "${timeout_cmd} $cmd $redirect '$filepath'"
  else
- eval "${timeout_cmd} $cmd" "$redirect" "$filepath"
- if [ $? -ne 0 ]; then
+ RC=0
+ eval "${timeout_cmd} $cmd" "$redirect" "$filepath" || RC=$?
+ if [ $RC -ne 0 ]; then
  echo "Command: $cmd timedout after ${TIMEOUT_MIN} minutes."
  fi
  fi
@@ -983,26 +984,30 @@ save_warmboot_files() {
 save_crash_files() {
  # archive core dump files
  trap 'handle_error $? $LINENO' ERR
- for file in $(find_files "/var/core/"); do
- # don't gzip already-gzipped log files :)
- if [ -z "${file##*.gz}" ]; then
- save_file $file core false
- else
- save_file $file core true
- fi
- done
+ if [ -d /var/core/ ]; then
+ for file in $(find_files "/var/core/"); do
+ # don't gzip already-gzipped log files :)
+ if [ -z "${file##*.gz}" ]; then
+ save_file $file core false
+ else
+ save_file $file core true
+ fi
+ done
+ fi
 
  # archive kernel dump files
- [ -d /var/crash/ ] && for file in $(find_files "/var/crash/"); do
- # don't gzip already-gzipped dmesg files :)
- if [ ! ${file} = "/var/crash/kexec_cmd" -a ! ${file} = "/var/crash/export" ]; then
- if [[ ${file} == *"kdump."* ]]; then
- save_file $file kdump false
- else
- save_file $file kdump true
+ if [ -d /var/crash/ ]; then
+ for file in $(find_files "/var/crash/"); do
+ # don't gzip already-gzipped dmesg files :)
+ if [ ! ${file} = "/var/crash/kexec_cmd" -a ! ${file} = "/var/crash/export" ]; then
+ if [[ ${file} == *"kdump."* ]]; then
+ save_file $file kdump false
+ else
+ save_file $file kdump true
+ fi
  fi
- fi
- done
+ done
+ fi
 }
 
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