goto_xs.t

UNIX下perl实现代码

#!./perl
# tests for "goto &sub"-ing into XSUBs

# $RCSfile$$Revision$$Date$

# Note: This only tests things that should *work*.  At some point, it may
#       be worth while to write some failure tests for things that should
#       *break* (such as calls with wrong number of args).  For now, I'm
#       guessing that if all of these work correctly, the bad ones will
#       break correctly as well.

chdir 't' if -d 't';
@INC = '../lib';
$ENV{PERL5LIB} = "../lib";

# turn warnings into fatal errors
$SIG{__WARN__} = sub { die "WARNING: @_" } ;

BEGIN { $| = 1; }
eval 'require Fcntl'
  or do { print "1..0\n# Fcntl unavailable, can't test XS goto.\n"; exit 0 };

print "1..10\n";

# We don't know what symbols are defined in platform X's system headers.
# We don't even want to guess, because some platform out there will
# likely do the unthinkable.  However, Fcntl::constant("LOCK_SH",0)
# should always return a value, even on platforms which don't define the
# cpp symbol; Fcntl.xs says:
#           /* We support flock() on systems which don't have it, so
#              always supply the constants. */
# If this ceases to be the case, we're in trouble. =)
$VALID = 'LOCK_SH';

### First, we check whether Fcntl::constant returns sane answers.
# Fcntl::constant("LOCK_SH",0) should always succeed.

$value = Fcntl::constant($VALID,0);
print((!defined $value)
      ? "not ok 1\n# Sanity check broke, remaining tests will fail.\n"
      : "ok 1\n");

### OK, we're ready to do real tests.

# test "goto &function_constant"
sub goto_const { goto &Fcntl::constant; }

$ret = goto_const($VALID,0);
print(($ret == $value) ? "ok 2\n" : "not ok 2\n# ($ret != $value)\n");

# test "goto &$function_package_and_name"
$FNAME1 = 'Fcntl::constant';
sub goto_name1 { goto &$FNAME1; }

$ret = goto_name1($VALID,0);
print(($ret == $value) ? "ok 3\n" : "not ok 3\n# ($ret != $value)\n");

# test "goto &$function_package_and_name" again, with dirtier stack
$ret = goto_name1($VALID,0);
print(($ret == $value) ? "ok 4\n" : "not ok 4\n# ($ret != $value)\n");
$ret = goto_name1($VALID,0);
print(($ret == $value) ? "ok 5\n" : "not ok 5\n# ($ret != $value)\n");

# test "goto &$function_name" from local package
package Fcntl;
$FNAME2 = 'constant';
sub goto_name2 { goto &$FNAME2; }
package main;

$ret = Fcntl::goto_name2($VALID,0);
print(($ret == $value) ? "ok 6\n" : "not ok 6\n# ($ret != $value)\n");

# test "goto &$function_ref"
$FREF = \&Fcntl::constant;
sub goto_ref { goto &$FREF; }

$ret = goto_ref($VALID,0);
print(($ret == $value) ? "ok 7\n" : "not ok 7\n# ($ret != $value)\n");

### tests where the args are not on stack but in GvAV(defgv) (ie, @_)

# test "goto &function_constant" from a sub called without arglist
sub call_goto_const { &goto_const; }

$ret = call_goto_const($VALID,0);
print(($ret == $value) ? "ok 8\n" : "not ok 8\n# ($ret != $value)\n");

# test "goto &$function_package_and_name" from a sub called without arglist
sub call_goto_name1 { &goto_name1; }

$ret = call_goto_name1($VALID,0);
print(($ret == $value) ? "ok 9\n" : "not ok 9\n# ($ret != $value)\n");

# test "goto &$function_ref" from a sub called without arglist
sub call_goto_ref { &goto_ref; }

$ret = call_goto_ref($VALID,0);
print(($ret == $value) ? "ok 10\n" : "not ok 10\n# ($ret != $value)\n");