1
    2
    3
    4
    5
    6
    7
    8
    9
   10
   11
   12
   13
   14
   15
   16
   17
   18
   19
   20
   21
   22
   23
   24
   25
   26
   27
   28
   29
   30
   31
   32
   33
   34
   35
   36
   37
   38
   39
   40
   41
   42
   43
   44
   45
   46
   47
   48
   49
   50
   51
   52
   53
   54
   55
   56
   57
   58
   59
   60
   61
   62
   63
   64
   65
   66
   67
   68
   69
   70
   71
   72
   73
   74
   75
   76
   77
   78
   79
   80
   81
   82
   83
   84
   85
   86
   87
   88
   89
   90
   91
   92
   93
   94
   95
   96
   97
   98
   99
  100
  101
  102
  103
  104
  105
  106
  107
  108
  109
  110
  111
  112
  113
  114
  115
  116
  117
  118
  119
  120
  121
  122
  123
  124
  125
  126
  127
  128
  129
  130
  131
  132
  133
  134
  135
  136
  137
  138
  139
  140
  141
  142
  143
  144
  145
  146
  147
  148
  149
  150
  151
  152
  153
  154
  155
  156
  157
  158
  159
  160
  161
  162
  163
  164
  165
  166
  167
  168
  169
  170
  171
  172
  173
  174
  175
  176
  177
  178
  179
  180
  181
  182
  183
  184
  185
  186
  187
  188
  189
  190
  191
  192
  193
  194
  195
  196
  197
  198
  199
  200
  201
  202
  203
  204
  205
  206
  207
  208
  209
  210
  211
  212
  213
  214
  215
  216
  217
  218
  219
  220
  221
  222
  223
  224
  225
  226
  227
  228
  229
  230
  231
  232
  233
  234
  235
  236
  237
  238
  239
  240
  241
  242
  243
  244
  245
  246
  247
  248
  249
  250
  251
  252
  253
  254
  255
  256
  257
  258
  259
  260
  261
  262
  263
  264
  265
  266
  267
  268
  269
  270
  271
  272
  273
  274
  275
  276
  277
  278
  279
  280
  281
  282
  283
  284
  285
  286
  287
  288
  289
  290
  291
  292
  293
  294
  295
  296
  297
  298
  299
  300
  301
  302
  303
  304
  305
  306
  307
  308
  309
  310
  311
  312
  313
  314

media / PRESUBMIT.py [blame]

# Copyright 2013 The Chromium Authors
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
"""Top-level presubmit script for Chromium media component.

See http://dev.chromium.org/developers/how-tos/depottools/presubmit-scripts
for more details about the presubmit API built into depot_tools.
"""

import os
import re

PRESUBMIT_VERSION = '2.0.0'

# Well-defined simple classes containing only <= 4 ints, or <= 2 floats.
BASE_TIME_TYPES = [
    'base::Time',
    'base::TimeDelta',
    'base::TimeTicks',
]

BASE_TIME_TYPES_RE = re.compile(r'\bconst (%s)&' % '|'.join(BASE_TIME_TYPES))


def _FilterFile(affected_file):
    """Return true if the file could contain code requiring a presubmit check."""
    return affected_file.LocalPath().endswith(
        ('.h', '.cc', '.cpp', '.cxx', '.mm'))


def _CheckForUseOfWrongClock(input_api, output_api):
    """Make sure new lines of media code don't use a clock susceptible to skew."""

    # Regular expression that should detect any explicit references to the
    # base::Time type (or base::Clock/DefaultClock), whether in using decls,
    # typedefs, or to call static methods.
    base_time_type_pattern = r'(^|\W)base::(Time|Clock|DefaultClock)(\W|$)'

    # Regular expression that should detect references to the base::Time class
    # members, such as a call to base::Time::Now.
    base_time_member_pattern = r'(^|\W)(Time|Clock|DefaultClock)::'

    # Regular expression to detect "using base::Time" declarations.  We want to
    # prevent these from triggering a warning.  For example, it's perfectly
    # reasonable for code to be written like this:
    #
    #   using base::Time;
    #   ...
    #   int64_t foo_us = foo_s * Time::kMicrosecondsPerSecond;
    using_base_time_decl_pattern = r'^\s*using\s+(::)?base::Time\s*;'

    # Regular expression to detect references to the kXXX constants in the
    # base::Time class.  We want to prevent these from triggering a warning.
    base_time_konstant_pattern = r'(^|\W)Time::k\w+'

    # Regular expression to detect usage of openscreen clock types, which are
    # allowed depending on DEPS rules.
    openscreen_time_pattern = r'(^|\W)openscreen::Clock\s*'

    problem_re = input_api.re.compile(r'(' + base_time_type_pattern + r')|(' +
                                      base_time_member_pattern + r')')
    exception_re = input_api.re.compile(r'(' + using_base_time_decl_pattern +
                                        r')|(' + base_time_konstant_pattern +
                                        r')|(' + openscreen_time_pattern +
                                        r')')
    problems = []
    for f in input_api.AffectedSourceFiles(_FilterFile):
        for line_number, line in f.ChangedContents():
            if problem_re.search(line):
                if not exception_re.search(line):
                    problems.append('  %s:%d\n    %s' %
                                    (f.LocalPath(), line_number, line.strip()))

    if problems:
        return [
            output_api.PresubmitPromptOrNotify(
                'You added one or more references to the base::Time class and/or one\n'
                'of its member functions (or base::Clock/DefaultClock). In media\n'
                'code, it is rarely correct to use a clock susceptible to time skew!\n'
                'Instead, could you use base::TimeTicks to track the passage of\n'
                'real-world time?\n\n' + '\n'.join(problems))
        ]
    else:
        return []


def _CheckForHistogramOffByOne(input_api, output_api):
    """Make sure histogram enum maxes are used properly"""

    # A general-purpose chunk of regex to match whitespace and/or comments
    # that may be interspersed with the code we're interested in:
    comment = r'/\*.*?\*/|//[^\n]*'
    whitespace = r'(?:[\n\t ]|(?:' + comment + r'))*'

    # The name is assumed to be a literal string.
    histogram_name = r'"[^"]*"'

    # This can be an arbitrary expression, so just ensure it isn't a ; to prevent
    # matching past the end of this statement.
    histogram_value = r'[^;]*'

    # In parens so we can retrieve it for further checks.
    histogram_max = r'([^;,]*)'

    # This should match a uma histogram enumeration macro expression.
    uma_macro_re = input_api.re.compile(r'\bUMA_HISTOGRAM_ENUMERATION\(' +
                                        whitespace + histogram_name + r',' +
                                        whitespace + histogram_value + r',' +
                                        whitespace + histogram_max +
                                        whitespace + r'\)' + whitespace +
                                        r';(?:' + whitespace +
                                        r'\/\/ (PRESUBMIT_IGNORE_UMA_MAX))?')

    uma_max_re = input_api.re.compile(r'.*(?:Max|MAX).* \+ 1')

    problems = []

    for f in input_api.AffectedSourceFiles(_FilterFile):
        contents = input_api.ReadFile(f)

        # We want to match across lines, but still report a line number, so we keep
        # track of the line we're on as we search through the file.
        line_number = 1

        # We search the entire file, then check if any violations are in the changed
        # areas, this is inefficient, but simple. A UMA_HISTOGRAM_ENUMERATION call
        # will often span multiple lines, so finding a match looking just at the
        # deltas line-by-line won't catch problems.
        match = uma_macro_re.search(contents)
        while match:
            line_number += contents.count('\n', 0, match.start())
            max_arg = match.group(1)  # The third argument.

            if (not uma_max_re.match(max_arg)
                    and match.group(2) != 'PRESUBMIT_IGNORE_UMA_MAX'):
                uma_range = range(match.start(), match.end() + 1)
                # Check if any part of the match is in the changed lines:
                for num, line in f.ChangedContents():
                    if line_number <= num <= line_number + match.group().count(
                            '\n'):
                        problems.append('%s:%d' % (f, line_number))
                        break

            # Strip off the file contents up to the end of the match and update the
            # line number.
            contents = contents[match.end():]
            line_number += match.group().count('\n')
            match = uma_macro_re.search(contents)

    if problems:
        return [
            output_api.PresubmitError(
                'UMA_HISTOGRAM_ENUMERATION reports in src/media/ are expected to adhere\n'
                'to the following guidelines:\n'
                ' - The max value (3rd argument) should be an enum value equal to the\n'
                '   last valid value, e.g. FOO_MAX = LAST_VALID_FOO.\n'
                ' - 1 must be added to that max value.\n'
                'Contact dalecurtis@chromium.org if you have questions.',
                problems)
        ]

    return []


def _CheckPassByValue(input_api, output_api):
    """Check that base::Time and derived classes are passed by value, and not by
  const reference """

    problems = []

    for f in input_api.AffectedSourceFiles(_FilterFile):
        for line_number, line in f.ChangedContents():
            if BASE_TIME_TYPES_RE.search(line):
                problems.append('%s:%d' % (f, line_number))

    if problems:
        return [
            output_api.PresubmitError(
                'base::Time and derived classes should be passed by value and not by\n'
                'const ref, see base/time/time.h for more information.',
                problems)
        ]
    return []


def _CheckForUseOfLazyInstance(input_api, output_api):
    """Check that base::LazyInstance is not used."""

    problems = []

    lazy_instance_re = re.compile(r'(^|\W)base::LazyInstance<')

    for f in input_api.AffectedSourceFiles(_FilterFile):
        for line_number, line in f.ChangedContents():
            if lazy_instance_re.search(line):
                problems.append('%s:%d' % (f, line_number))

    if problems:
        return [
            output_api.PresubmitError(
                'base::LazyInstance is deprecated; use a thread safe static.',
                problems)
        ]
    return []


def _CheckNoLoggingOverrideInHeaders(input_api, output_api):
    """Checks to make sure no .h files include logging_override_if_enabled.h."""
    files = []
    pattern = input_api.re.compile(
        r'^#include\s*"media/base/logging_override_if_enabled.h"',
        input_api.re.MULTILINE)
    for f in input_api.AffectedSourceFiles(input_api.FilterSourceFile):
        if not f.LocalPath().endswith('.h'):
            continue
        contents = input_api.ReadFile(f)
        if pattern.search(contents):
            files.append(f)

    if len(files):
        return [
            output_api.PresubmitError(
                'Do not #include "logging_override_if_enabled.h" in header files, '
                'since it overrides DVLOG() in every file including the header. '
                'Instead, only include it in source files.', files)
        ]
    return []


def _CheckForNoV4L2AggregateInitialization(input_api, output_api):
    """Check that struct v4l2_* are not initialized as aggregates with a
  braced-init-list"""

    problems = []

    v4l2_aggregate_initializer_re = re.compile(
        r'(^|\W)struct.+v4l2_.+=.+{+}+;')

    for f in input_api.AffectedSourceFiles(_FilterFile):
        for line_number, line in f.ChangedContents():
            if v4l2_aggregate_initializer_re.search(line):
                problems.append('%s:%d' % (f, line_number))

    if problems:
        return [
            output_api.PresubmitPromptWarning(
                'Avoid initializing V4L2 structures with braced-init-lists, i.e. as '
                'aggregates. V4L2 structs often contain unions of various sized members: '
                'when a union is initialized by aggregate initialization, only the first '
                'non-static member is initialized, leaving other members unitialized if '
                'they are larger. Use memset instead.', problems)
        ]
    return []


def _CheckChangeInBundle(input_api, output_api):
    import sys
    old_sys_path = sys.path[:]
    results = []
    try:
        sys.path.append(input_api.change.RepositoryRoot())
        from build.ios import presubmit_support
        results += presubmit_support.CheckBundleData(input_api, output_api,
                                                     'unit_tests_bundle_data')
    finally:
        sys.path = old_sys_path
    return results


def _CheckIfGenerateGnTestsFail(input_api, output_api):
    """Error if generate_gn.py was changed and tests are now failing."""
    should_run_tests = False
    generate_gn_re = re.compile(r'.*generate_gn.*\.py$')
    for f in input_api.AffectedFiles():
        if generate_gn_re.match(f.LocalPath()):
            should_run_tests = True
            break

    errors = []
    if should_run_tests:
        errors += input_api.RunTests(
            input_api.canned_checks.GetUnitTests(
                input_api,
                output_api, [
                    os.path.join('ffmpeg', 'scripts',
                                 'generate_gn_unittest_wrapper.py')
                ],
                run_on_python2=False,
                run_on_python3=True,
                skip_shebang_check=False))

    return errors


def _CheckChange(input_api, output_api):
    results = []
    results.extend(_CheckForUseOfWrongClock(input_api, output_api))
    results.extend(_CheckPassByValue(input_api, output_api))
    results.extend(_CheckForHistogramOffByOne(input_api, output_api))
    results.extend(_CheckForUseOfLazyInstance(input_api, output_api))
    results.extend(_CheckNoLoggingOverrideInHeaders(input_api, output_api))
    results.extend(
        _CheckForNoV4L2AggregateInitialization(input_api, output_api))
    results.extend(_CheckChangeInBundle(input_api, output_api))
    results.extend(_CheckIfGenerateGnTestsFail(input_api, output_api))
    return results


def CheckChangeOnUpload(input_api, output_api):
    return _CheckChange(input_api, output_api)


def CheckChangeOnCommit(input_api, output_api):
    return _CheckChange(input_api, output_api)