tests: improve test coverage for ls stat checks

* tests/ls/stat-free-color.sh: Check for the availability
of various stat calls individually, and add statx() and fstatat64()
to the list to check.  Fix the stat counting logic to
ignore lines like "+++ exited with 0 +++".
* tests/ls/stat-free-symlinks.sh: Check syscalls other than stat().

2 files changed, 44 insertions, 19 deletions

diff --git a/tests/ls/stat-free-color.sh b/tests/ls/stat-free-color.sh
index a1766aa5e..00942f774 100755
--- a/tests/ls/stat-free-color.sh
+++ b/tests/ls/stat-free-color.sh
@@ -18,15 +18,17 @@
 
 . "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
 print_ver_ ls
-
-# Note this list of _file name_ stat functions must be
-# as cross platform as possible and so doesn't include
-# fstatat64 as that's not available on aarch64 for example.
-stats='stat,lstat,stat64,lstat64,newfstatat'
-
-require_strace_ $stats
+require_strace_ stat
 require_dirent_d_type_
 
+stats='stat'
+# List of other _file name_ stat functions to increase coverage.
+other_stats='statx lstat stat64 lstat64 newfstatat fstatat64'
+for stat in $other_stats; do
+  strace -qe "$stat" true > /dev/null 2>&1 &&
+    stats="$stats,$stat"
+done
+
 # Disable enough features via LS_COLORS so that ls --color
 # can do its job without calling stat (other than the obligatory
 # one-call-per-command-line argument).
@@ -59,8 +61,8 @@ eval $(dircolors -b color-without-stat)
 # invocation under test.
 mkdir d || framework_failure_
 
-strace -o log1 -e $stats ls --color=always d || fail=1
-n_stat1=$(wc -l < log1) || framework_failure_
+strace -q -o log1 -e $stats ls --color=always d || fail=1
+n_stat1=$(grep -vF '+++' log1 | wc -l) || framework_failure_
 
 test $n_stat1 = 0 \
   && skip_ 'No stat calls recognized on this platform'
@@ -74,8 +76,8 @@ mkdir d/subdir \
   || framework_failure_
 
 # Invocation under test.
-strace -o log2 -e $stats ls --color=always d || fail=1
-n_stat2=$(wc -l < log2) || framework_failure_
+strace -q -o log2 -e $stats ls --color=always d || fail=1
+n_stat2=$(grep -vF '+++' log2 | wc -l) || framework_failure_
 
 # Expect the same number of stat calls.
 test $n_stat1 = $n_stat2 \
diff --git a/tests/ls/stat-free-symlinks.sh b/tests/ls/stat-free-symlinks.sh
index a786145db..80e5a357a 100755
--- a/tests/ls/stat-free-symlinks.sh
+++ b/tests/ls/stat-free-symlinks.sh
@@ -20,6 +20,28 @@
 print_ver_ ls
 require_strace_ stat
 
+stats='stat'
+# List of other _file name_ stat functions to increase coverage.
+other_stats='statx lstat stat64 lstat64 newfstatat fstatat64'
+for stat in $other_stats; do
+  strace -qe "$stat" true > /dev/null 2>&1 &&
+    stats="$stats,$stat"
+done
+
+# The system may perform additional stat-like calls before main.
+# Furthermore, underlying library functions may also implicitly
+# add an extra stat call, e.g. opendir since glibc-2.21-360-g46f894d.
+# To avoid counting those, first get a baseline count for running
+# ls with one empty directory argument.  Then, compare that with the
+# invocation under test.
+mkdir d || framework_failure_
+strace -q -o log1 -e $stats ls -F --color=always d || fail=1
+n_stat1=$(grep -vF '+++' log1 | wc -l) || framework_failure_
+
+test $n_stat1 = 0 \
+  && skip_ 'No stat calls recognized on this platform'
+
+
 touch x || framework_failure_
 chmod a+x x || framework_failure_
 ln -s x link-to-x || framework_failure_
@@ -32,21 +54,22 @@ ln -s x link-to-x || framework_failure_
 # symlink and an executable file properly.
 
 LS_COLORS='or=0:mi=0:ex=01;32:ln=01;35' \
-  strace -qe stat ls -F --color=always x link-to-x > out.tmp 2> err || fail=1
-# Elide info messages strace can send to stdout of the form:
-#   [ Process PID=1234 runs in 32 bit mode. ]
-sed '/Process PID=/d' out.tmp > out
+  strace -qe $stats -o log2 ls -F --color=always x link-to-x > out.tmp || fail=1
+n_stat2=$(grep -vF '+++' log2 | wc -l) || framework_failure_
 
-# With coreutils 6.9 and earlier, this file would contain a
-# line showing ls had called stat on "x".
-grep '^stat("x"' err && fail=1
+# Expect one more stat call,
+# which failed with coreutils 6.9 and earlier, which had 2.
+test $n_stat1 = $(($n_stat2 - 1)) \
+  || { fail=1; head -n30 log*; }
 
 # Check that output is colorized, as requested, too.
 {
   printf '\033[0m\033[01;35mlink-to-x\033[0m@\n'
   printf '\033[01;32mx\033[0m*\n'
 } > exp || fail=1
-
+# Elide info messages strace can send to stdout of the form:
+#   [ Process PID=1234 runs in 32 bit mode. ]
+sed '/Process PID=/d' out.tmp > out
 compare exp out || fail=1
 
 Exit $fail