# PR 11223.  Make sure we can handle large amounts of procfs write data.

set test "PROCFS_WRITE"

if {![installtest_p]} { untested $test; return }

proc proc_write_value { test path value} {
    if [catch {open $path WRONLY} channel] {
	fail "$test $channel"
    } else {
	puts $channel $value
	close $channel
	pass "$test wrote $value"
    }
}

# This test string is ~4224 bytes long (66 lines of 64 chars).  The
# procfs kernel system will use a buffer of 4K.  Our string of ~4224
# should take around 9 trips through the write function (4224 chars /
# 512 bytes per systemtap string = ~9 trips).
#
# The kernel reuses the 4K buffer for the 9th trip and doesn't null
# terminate the string.  Instead, it tells consumers how many bytes
# are present.
#
# We want to make sure we can handle > 4K worth of data properly.
set test_string \
"  0:12345678901234567890123456789012345678901234567890123456789
  1:12345678901234567890123456789012345678901234567890123456789
  2:12345678901234567890123456789012345678901234567890123456789
  3:12345678901234567890123456789012345678901234567890123456789
  4:12345678901234567890123456789012345678901234567890123456789
  5:12345678901234567890123456789012345678901234567890123456789
  6:12345678901234567890123456789012345678901234567890123456789
  7:12345678901234567890123456789012345678901234567890123456789
  8:12345678901234567890123456789012345678901234567890123456789
  9:12345678901234567890123456789012345678901234567890123456789
 10:12345678901234567890123456789012345678901234567890123456789
 11:12345678901234567890123456789012345678901234567890123456789
 12:12345678901234567890123456789012345678901234567890123456789
 13:12345678901234567890123456789012345678901234567890123456789
 14:12345678901234567890123456789012345678901234567890123456789
 15:12345678901234567890123456789012345678901234567890123456789
 16:12345678901234567890123456789012345678901234567890123456789
 17:12345678901234567890123456789012345678901234567890123456789
 18:12345678901234567890123456789012345678901234567890123456789
 19:12345678901234567890123456789012345678901234567890123456789
 20:12345678901234567890123456789012345678901234567890123456789
 21:12345678901234567890123456789012345678901234567890123456789
 22:12345678901234567890123456789012345678901234567890123456789
 23:12345678901234567890123456789012345678901234567890123456789
 24:12345678901234567890123456789012345678901234567890123456789
 25:12345678901234567890123456789012345678901234567890123456789
 26:12345678901234567890123456789012345678901234567890123456789
 27:12345678901234567890123456789012345678901234567890123456789
 28:12345678901234567890123456789012345678901234567890123456789
 29:12345678901234567890123456789012345678901234567890123456789
 30:12345678901234567890123456789012345678901234567890123456789
 31:12345678901234567890123456789012345678901234567890123456789
 32:12345678901234567890123456789012345678901234567890123456789
 33:12345678901234567890123456789012345678901234567890123456789
 34:12345678901234567890123456789012345678901234567890123456789
 35:12345678901234567890123456789012345678901234567890123456789
 36:12345678901234567890123456789012345678901234567890123456789
 37:12345678901234567890123456789012345678901234567890123456789
 38:12345678901234567890123456789012345678901234567890123456789
 39:12345678901234567890123456789012345678901234567890123456789
 40:12345678901234567890123456789012345678901234567890123456789
 41:12345678901234567890123456789012345678901234567890123456789
 42:12345678901234567890123456789012345678901234567890123456789
 43:12345678901234567890123456789012345678901234567890123456789
 44:12345678901234567890123456789012345678901234567890123456789
 45:12345678901234567890123456789012345678901234567890123456789
 46:12345678901234567890123456789012345678901234567890123456789
 47:12345678901234567890123456789012345678901234567890123456789
 48:12345678901234567890123456789012345678901234567890123456789
 49:12345678901234567890123456789012345678901234567890123456789
 50:12345678901234567890123456789012345678901234567890123456789
 51:12345678901234567890123456789012345678901234567890123456789
 52:12345678901234567890123456789012345678901234567890123456789
 53:12345678901234567890123456789012345678901234567890123456789
 54:12345678901234567890123456789012345678901234567890123456789
 55:12345678901234567890123456789012345678901234567890123456789
 56:12345678901234567890123456789012345678901234567890123456789
 57:12345678901234567890123456789012345678901234567890123456789
 58:12345678901234567890123456789012345678901234567890123456789
 59:12345678901234567890123456789012345678901234567890123456789
 60:12345678901234567890123456789012345678901234567890123456789
 61:12345678901234567890123456789012345678901234567890123456789
 62:12345678901234567890123456789012345678901234567890123456789
 63:12345678901234567890123456789012345678901234567890123456789
 64:12345678901234567890123456789012345678901234567890123456789
 65:12345678901234567890123456789012345678901234567890123456789
 66:12345678901234567890123456789012345678901234567890123456789"

# Now we need the version of the above string that expect will look
# for.  So, we need to convert all '\n' to '\r\n' and add a trailing
# '\r\n'.
regsub -all {\n} $test_string "\r\n" test_string2
set test_string2 "$test_string2\r\n"

proc proc_write_test {} {
    global test test_string
    set path "/proc/systemtap/$test/command"

    proc_write_value $test $path $test_string
    return 0;
}

set systemtap_write_script {
    global iteration = 0
    global saved_value[20]

    probe procfs("command").write {
	saved_value[iteration] = $value
	iteration++
    }

    probe begin {
        printf("systemtap starting probe\n")
    }

    probe end {
        printf("systemtap ending probe\n")
	for (i = 0; i < iteration; i++) {
	    printf("%s", saved_value[i])
	}
    }
}

# We're forcing the MAXSTRINGLEN to be 512 chars to make sure we know
# what we're testing.
stap_run $test proc_write_test $test_string2 -DMAXSTRINGLEN=512 \
    -e $systemtap_write_script -m $test
exec /bin/rm -f ${test}.ko