MDEV-15503: mtr fix --stracebb-10.3-anel-mtr-correct-strace

$glob_mysql_test_dir was the wrong directory for strace output as
it was for in-tree builds only so failed for:
* out of tree builds
* --parallel; and
* --mem

strace output wasn't saved.

strace-option never replaced existing arguments (so ammended
documentation).

strace-client didn't accept an argument as described.

Replaced specification of client with this with 'stracer' to be
consistent with --debugger option.

For consistency with debugger options, --client-strace was added to
execute the strace on the mysqltest.

Example:

$ mysql-test/mtr --strace --client-strace  --mem --parallel=3  main.select
Logging: /home/dan/software_projects/mariadb-server/mysql-test/mysql-test-run.pl  --strace --client-strace --mem --parallel=3 main.select
vardir: /home/dan/software_projects/build-mariadb-10.3/mysql-test/var
Checking leftover processes...
Removing old var directory...
Creating var directory '/home/dan/software_projects/build-mariadb-10.3/mysql-test/var'...
 - symlinking 'var' to '/dev/shm/var_auto_0v2E'
Checking supported features...
MariaDB Version 10.3.7-MariaDB
 - SSL connections supported
Collecting tests...
Installing system database...

==============================================================================

TEST                                  WORKER RESULT   TIME (ms) or COMMENT
--------------------------------------------------------------------------

worker[1] Using MTR_BUILD_THREAD 300, with reserved ports 16000..16019
worker[3]  - 'localhost:16040' was not free
worker[2] Using MTR_BUILD_THREAD 301, with reserved ports 16020..16039
worker[3] Using MTR_BUILD_THREAD 303, with reserved ports 16060..16079
main.select                              w1 [ pass ]   7310
--------------------------------------------------------------------------
The servers were restarted 0 times
Spent 7.310 of 11 seconds executing testcases

Completed: All 1 tests were successful.

$ find mysql-test/var/ -name \*strace -ls
  5213766   1212 -rw-r--r--   1  dan      dan       1237817 May 20 16:47 mysql-test/var/1/mysqltest.strace
  5214733  13016 -rw-r--r--   1  dan      dan      13328335 May 20 16:47 mysql-test/var/1/mysqld.1.strace

$ mysql-test/mtr --strace --client-strace --strace-option='-e' --strace-option='trace=openat'  --mem --parallel=3  main.select
...
$ find mysql-test/var/ -name \*strace -ls                                                              5220790      8 -rw-r--r--   1  dan      dan          6291 May 20 17:02 mysql-test/var/3/mysqltest.strace
  5224140    308 -rw-r--r--   1  dan      dan        314356 May 20 17:02 mysql-test/var/3/mysqld.1.strace
$ more mysql-test/var/3/mysqltest.strace
1692  openat(AT_FDCWD, "/home/dan/software_projects/mariadb-server/libmysql/.libs/tls/x86_64/x86_64/libpthread.so.0", O_RDONLY|O_CLOEXEC) =
-1 ENOENT (No such file or directory)
1692  openat(AT_FDCWD, "/home/dan/software_projects/mariadb-server/libmysql/.libs/tls/x86_64/libpthread.so.0", O_RDONLY|O_CLOEXEC) = -1 ENOE
NT (No such file or directory)
....

1 files changed, 25 insertions, 21 deletions

diff --git a/mysql-test/mysql-test-run.pl b/mysql-test/mysql-test-run.pl
index 12fb5de4678..4bbbf220209 100755
--- a/mysql-test/mysql-test-run.pl
+++ b/mysql-test/mysql-test-run.pl
@@ -324,7 +324,8 @@ my $opt_valgrind_mysqld= 0;
 my $opt_valgrind_mysqltest= 0;
 my @valgrind_args;
 my $opt_strace= 0;
-my $opt_strace_client;
+my $opt_stracer;
+my $opt_client_strace = 0;
 my @strace_args;
 my $opt_valgrind_path;
 my $valgrind_reports= 0;
@@ -1329,9 +1330,10 @@ sub command_line_setup {
 	     'debugger=s'               => \$opt_debugger,
 	     'boot-dbx'                 => \$opt_boot_dbx,
 	     'client-debugger=s'        => \$opt_client_debugger,
-             'strace'			=> \$opt_strace,
-             'strace-client'            => \$opt_strace_client,
-             'strace-option=s'          => \@strace_args,
+             'strace'              => \$opt_strace,
+             'strace-option=s'     => \@strace_args,
+             'client-strace'       => \$opt_client_strace,
+             'stracer=s'           => \$opt_stracer,
              'max-save-core=i'          => \$opt_max_save_core,
              'max-save-datadir=i'       => \$opt_max_save_datadir,
              'max-test-fail=i'          => \$opt_max_test_fail,
@@ -1927,7 +1929,7 @@ sub command_line_setup {
 	       join(" ", @valgrind_args), "\"");
   }
 
-  if (@strace_args)
+  if (@strace_args || $opt_stracer)
   {
     $opt_strace=1;
   }
@@ -5721,14 +5723,6 @@ sub start_mysqltest ($) {
     mtr_add_arg($args, "--non-blocking-api");
   }
 
-  if ( $opt_strace_client )
-  {
-    $exe=  $opt_strace_client || "strace";
-    mtr_add_arg($args, "-o");
-    mtr_add_arg($args, "%s/log/mysqltest.strace", $opt_vardir);
-    mtr_add_arg($args, "$exe_mysqltest");
-  }
-
   mtr_add_arg($args, "--timer-file=%s/log/timer", $opt_vardir);
 
   if ( $opt_compress )
@@ -5794,6 +5788,14 @@ sub start_mysqltest ($) {
     mtr_add_arg($args, "%s", $_) for @args_saved;
   }
 
+  if ( $opt_client_strace )
+  {
+    my @args_saved = @$args;
+    mtr_init_args(\$args);
+    strace_arguments($args, \$exe, "mysqltest");
+    mtr_add_arg($args, "%s", $_) for @args_saved;
+  }
+
   if ($opt_force > 1)
   {
     mtr_add_arg($args, "--continue-on-error");
@@ -6118,16 +6120,19 @@ sub strace_arguments {
   my $args= shift;
   my $exe=  shift;
   my $mysqld_name= shift;
+  my $output= sprintf("%s/%s.strace", $opt_vardir, $mysqld_name);
 
   mtr_add_arg($args, "-f");
-  mtr_add_arg($args, "-o%s/var/log/%s.strace", $glob_mysql_test_dir, $mysqld_name);
+  mtr_add_arg($args, "-o%s", $output);
+
+  $mysqld_logs{$output}= 1;
 
-  # Add strace options, can be overridden by user
+  # Add strace options
   mtr_add_arg($args, '%s', $_) for (@strace_args);
 
   mtr_add_arg($args, $$exe);
 
-  $$exe= "strace";
+  $$exe=  $opt_stracer || "strace";
 
   if ($exe_libtool)
   {
@@ -6403,11 +6408,10 @@ Options for valgrind
 Options for strace
 
   strace                Run the "mysqld" executables using strace. Default
-                        options are -f -o var/log/'mysqld-name'.strace
-  strace-option=ARGS    Option to give strace, replaces default option(s),
-  strace-client=[path]  Create strace output for mysqltest client, optionally
-                        specifying name and path to the trace program to use.
-                        Example: $0 --strace-client=ktrace
+                        options are -f -o 'vardir'/'mysqld-name'.strace
+  client-strace         Trace the "mysqltest".
+  strace-option=ARGS    Option to give strace, appends to existing options.
+  stracer=<EXE>         Specify name and path to the trace program to use.
 
 Misc options
   user=USER             User for connecting to mysqld(default: $opt_user)