Scripts: Fix exit status of xzgrep.

Omit the -q option from xz, gzip, and bzip2. With xz this shouldn't
matter. With gzip it's important because -q makes gzip replace SIGPIPE
with exit status 2. With bzip2 it's important because with -q bzip2
is completely silent if input is corrupt while other decompressors
still give an error message.

Avoiding exit status 2 from gzip is important because bzip2 uses
exit status 2 to indicate corrupt input. Before this commit xzgrep
didn't recognize corrupt .bz2 files because xzgrep was treating
exit status 2 as SIGPIPE for gzip compatibility.

zstd still needs -q because otherwise it is noisy in normal
operation.

The code to detect real SIGPIPE didn't check if the exit status
was due to a signal (>= 128) and so could ignore some other exit
status too.
This commit is contained in:
Lasse Collin 2021-01-11 23:28:52 +02:00
parent 09c331b03c
commit d655b8c9cb
1 changed files with 13 additions and 7 deletions

View File

@ -156,11 +156,11 @@ res=1
for i; do for i; do
case $i in case $i in
*[-.][zZ] | *_z | *[-.]gz | *.t[ag]z) uncompress="gzip -cdfq";; *[-.][zZ] | *_z | *[-.]gz | *.t[ag]z) uncompress="gzip -cdf";;
*[-.]bz2 | *[-.]tbz | *.tbz2) uncompress="bzip2 -cdfq";; *[-.]bz2 | *[-.]tbz | *.tbz2) uncompress="bzip2 -cdf";;
*[-.]lzo | *[-.]tzo) uncompress="lzop -cdfq";; *[-.]lzo | *[-.]tzo) uncompress="lzop -cdf";;
*[-.]zst | *[-.]tzst) uncompress="zstd -cdfq";; *[-.]zst | *[-.]tzst) uncompress="zstd -cdfq";; # zstd needs -q.
*) uncompress="$xz -cdfq";; *) uncompress="$xz -cdf";;
esac esac
# Fail if xz or grep (or sed) fails. # Fail if xz or grep (or sed) fails.
xz_status=$( xz_status=$(
@ -205,8 +205,14 @@ for i; do
# fail occurred previously, nothing worse can happen # fail occurred previously, nothing worse can happen
test $res -gt 1 && continue test $res -gt 1 && continue
test "$xz_status" -eq 0 || test "$xz_status" -eq 2 \ if test "$xz_status" -eq 0; then
|| test "$(kill -l "$xz_status" 2> /dev/null)" = "PIPE" || r=2 :
elif test "$xz_status" -ge 128 \
&& test "$(kill -l "$xz_status" 2> /dev/null)" = "PIPE"; then
:
else
r=2
fi
# still no match # still no match
test $r -eq 1 && continue test $r -eq 1 && continue