# Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

import os

import logging
from autotest_lib.client.bin import test, utils
from autotest_lib.client.common_lib import error
from optparse import OptionParser

FILE_CMD="file -m /usr/local/share/misc/magic.mgc"

class ToolchainOptionSet:
    def __init__(self, description, bad_files, whitelist_file):
        self.description = description
        self.bad_set = set(bad_files.splitlines())
        self.whitelist_set = set([])
        self.process_whitelist_with_private(whitelist_file)


    def process_whitelist_with_private(self, whitelist_file):
        whitelist_files = [whitelist_file]
        private_file = os.path.join(os.path.dirname(whitelist_file),
                                    "private_" +
                                    os.path.basename(whitelist_file))
        whitelist_files.append(private_file)
        self.process_whitelists(whitelist_files)


    def process_whitelist(self, whitelist_file):
        if not os.path.isfile(whitelist_file):
            self.whitelist_set = self.whitelist_set.union(set([]))
        else:
            f = open(whitelist_file)
            whitelist = [x for x in f.read().splitlines()
                                    if not x.startswith('#')]
            f.close()
            self.whitelist_set = self.whitelist_set.union(set(whitelist))
        self.filtered_set = self.bad_set.difference(self.whitelist_set)
        self.new_passes = self.whitelist_set.difference(self.bad_set)


    def process_whitelists(self, whitelist_files):
        for whitelist_file in whitelist_files:
            self.process_whitelist(whitelist_file)


    def get_fail_summary_message(self):
        m = "Test %s " % self.description
        m += "%d failures\n" % len(self.filtered_set)
        return m


    def get_fail_message(self):
        m = self.get_fail_summary_message()
        sorted_list = list(self.filtered_set)
        sorted_list.sort()
        m += "FAILED:\n%s\n\n" % "\n".join(sorted_list)
        return m


    def __str__(self):
        m = "Test %s " % self.description
        m += ("%d failures, %d in whitelist, %d in filtered, %d new passes " %
              (len(self.bad_set),
               len(self.whitelist_set),
               len(self.filtered_set),
               len(self.new_passes)))

        if len(self.filtered_set):
            sorted_list = list(self.filtered_set)
            sorted_list.sort()
            m += "FAILED:\n%s" % "\n".join(sorted_list)
        else:
            m += "PASSED!"

        if len(self.new_passes):
            sorted_list = list(self.new_passes)
            sorted_list.sort()
            m += ("\nNew passes (remove these from the whitelist):\n%s" %
                  "\n".join(sorted_list))
        logging.debug(m)
        return m


class platform_ToolchainOptions(test.test):
    version = 2

    def get_cmd(self, test_cmd, find_options=""):
        base_cmd = ("find '%s' -wholename %s -prune -o "
                    " -wholename /proc -prune -o "
                    " -wholename /dev -prune -o "
                    " -wholename /sys -prune -o "
                    " -wholename /mnt/stateful_partition -prune -o "
                    " -wholename /usr/local -prune -o "
                    # There are files in /home/chronos that cause false
                    # positives, and since that's noexec anyways, it should
                    # be skipped.
                    " -wholename '/home/chronos' -prune -o "
                    " %s "
                    " -not -name 'libstdc++.so.*' "
                    " -not -name 'libgcc_s.so.*' "
                    " -type f -executable -exec "
                    "sh -c '%s "
                    "{} | grep -q ELF && "
                    "(%s || echo {})' ';'")
        rootdir = "/"
        cmd = base_cmd % (rootdir, self.autodir, find_options, FILE_CMD,
                          test_cmd)
        return cmd


    # http://build.chromium.org/mirror/chromiumos/mirror/distfiles/
    # binutils-2.19.1.tar.bz2
    def setup(self, tarball="binutils-2.19.1.tar.bz2"):
        # clean
        if os.path.exists(self.srcdir):
            utils.system("rm -rf %s" % self.srcdir)

        tarball = utils.unmap_url(self.bindir, tarball, self.tmpdir)
        utils.extract_tarball_to_dir(tarball, self.srcdir)

        os.chdir(self.srcdir)
        utils.system("patch -p1 < ../binutils-2.19-arm.patch");
        utils.configure()
        utils.make(extra="CFLAGS+=\"-w\"")


    def create_and_filter(self, description, cmd, whitelist_file,
                          find_options=""):
        full_cmd = self.get_cmd(cmd, find_options)
        bad_files = utils.system_output(full_cmd)
        cso = ToolchainOptionSet(description, bad_files, whitelist_file)
        cso.process_whitelist_with_private(whitelist_file)
        return cso


    def run_once(self, rootdir="/", args=[]):
        """
        Do a find for all the ELF files on the system.
        For each one, test for compiler options that should have been used
        when compiling the file.

        For missing compiler options, print the files.
        """

        parser = OptionParser()
        parser.add_option('--hardfp',
                          dest='enable_hardfp',
                          default=False,
                          action='store_true',
                          help='Whether to check for hardfp binaries.')
        (options, args) = parser.parse_args(args)

        option_sets = []

        libc_glob = "/lib/libc-[0-9]*"
        os.chdir(self.srcdir)

        # We do not test binaries if they are built with Address Sanitizer
        # because it is a separate testing tool.
        no_asan_used = utils.system_output("binutils/readelf -s "
                                           "/opt/google/chrome/chrome | "
                                           "egrep -q \"__asan_init\" || "
                                           "echo no ASAN")
        if not no_asan_used:
          logging.debug("ASAN detected on /opt/google/chrome/chrome. "
                        "Will skip all checks.")
          return

        # Check that gold was used to build binaries.
        gold_cmd = ("binutils/readelf -S {} 2>&1 | "
                    "egrep -q \".note.gnu.gold-ve\"")
        gold_find_options = ""
        if utils.get_cpu_arch() == "arm":
          # gold is only enabled for Chrome on arm.
          gold_find_options = "-path \"/opt/google/chrome/chrome\""
        gold_whitelist = os.path.join(self.bindir, "gold_whitelist")
        option_sets.append(self.create_and_filter("gold",
                                                  gold_cmd,
                                                  gold_whitelist,
                                                  gold_find_options))

        # ARM arch doesn't have hardened.
        if utils.get_cpu_arch() != "arm":
            # Verify non-static binaries have BIND_NOW in dynamic section.
            now_cmd = ("(%s {} | grep -q statically) ||"
                       "binutils/readelf -d {} 2>&1 | "
                       "egrep -q \"BIND_NOW\"" % FILE_CMD)
            now_whitelist = os.path.join(self.bindir, "now_whitelist")
            option_sets.append(self.create_and_filter("-Wl,-z,now",
                                                      now_cmd,
                                                      now_whitelist))

            # Verify non-static binaries have RELRO program header.
            relro_cmd = ("(%s {} | grep -q statically) ||"
                         "binutils/readelf -l {} 2>&1 | "
                         "egrep -q \"GNU_RELRO\"" % FILE_CMD)
            relro_whitelist = os.path.join(self.bindir, "relro_whitelist")
            option_sets.append(self.create_and_filter("-Wl,-z,relro",
                                                      relro_cmd,
                                                      relro_whitelist))

            # Verify non-static binaries are dynamic (built PIE).
            pie_cmd = ("(%s {} | grep -q statically) ||"
                       "binutils/readelf -l {} 2>&1 | "
                       "egrep -q \"Elf file type is DYN\"" % FILE_CMD)
            pie_whitelist = os.path.join(self.bindir, "pie_whitelist")
            option_sets.append(self.create_and_filter("-fPIE",
                                                      pie_cmd,
                                                      pie_whitelist))

            # Verify all binaries have non-exec STACK program header.
            stack_cmd = ("binutils/readelf -lW {} 2>&1 | "
                         "egrep -q \"GNU_STACK.*RW \"")
            stack_whitelist = os.path.join(self.bindir, "stack_whitelist")
            option_sets.append(self.create_and_filter("Executable Stack",
                                                      stack_cmd,
                                                      stack_whitelist))

        if (options.enable_hardfp and utils.get_cpu_arch() == 'arm'):
            hardfp_cmd = ("binutils/readelf -A {} 2>&1 | "
                          "egrep -q \"Tag_ABI_VFP_args: VFP registers\"")
            hardfp_whitelist = os.path.join(self.bindir, "hardfp_whitelist")
            option_sets.append(self.create_and_filter("hardfp", hardfp_cmd,
                                                      hardfp_whitelist))

        fail_msg = ""

        # There is currently no way to clear binary prebuilts for all devs.
        # Thus, when a new check is added to this test, the test might fail
        # for users who have old prebuilts which have not been compiled
        # in the correct manner. Warn the user that if a test fails,
        # they might have to clear their prebuilts to make it pass.
        fail_summary_msg = "The following tests failed. If you expected " \
                           "the test to pass you may have stale binary " \
                           "prebuilts which are causing the failure. Try " \
                           "clearing binary prebuilts and rebuilding by " \
                           " running: ./setup_board --board=... --force\n\n"
        full_msg = "Test results:"
        num_fails = 0
        for cos in option_sets:
            if len(cos.filtered_set):
                num_fails += 1
                fail_msg += cos.get_fail_message() + "\n"
                fail_summary_msg += cos.get_fail_summary_message() + "\n"
            full_msg += str(cos) + "\n\n"

        logging.error(fail_msg)
        logging.debug(full_msg)
        if num_fails:
            raise error.TestFail(fail_summary_msg)