1 files changed, 183 insertions, 0 deletions
diff --git a/.gitlab-ci/generate-evdev-keycodes.py b/.gitlab-ci/generate-evdev-keycodes.py
new file mode 100755
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+++ b/.gitlab-ci/generate-evdev-keycodes.py
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+#!/usr/bin/env python3
+#
+# Usage: generate-evdev-keycodes.py keycodes/evdev.in > keycodes/evdev
+#
+# Generate the keycodes/evdev file from the names defined in
+# linux/input-event-codes.h
+#
+# Note that this script relies on libevdev to provide the key names and
+# those are compiled in. Ensure you have a recent-enough libevdev to
+# generate this list.
+#
+
+import argparse
+import contextlib
+import re
+import sys
+try:
+    import libevdev
+except ImportError:
+    print('WARNING: python-libevdev not available, cannot check for new evdev keycodes', file=sys.stderr)
+    sys.exit(77)
+
+
+# The marker to search for in the template file, replaced with our generated
+# codes.
+replacement_marker = '@evdevkeys@'
+
+# These markers are put into the result file and are used to detect
+# the section that we added when parsing an existing file.
+section_header = 'Key codes below are autogenerated'
+section_footer = 'End of autogenerated key codes'
+
+
+def evdev_codes():
+    '''
+    Return the dict {code, name} for all known evdev codes.
+
+    The list of names is compiled into libevdev.so, use a recent libevdev
+    release to get the most up-to-date list.
+    '''
+    codes = {}
+    for c in libevdev.EV_KEY.codes:
+        # 112 because that's where our 1:1 keycode entries historically
+        # started.
+        # Undefined keys are those with a code < KEY_MAX but without a
+        # #define in the kernel header file
+        if c.value < 112 or not c.is_defined:
+            continue
+
+        if c.name.startswith('BTN_') or c.name == 'KEY_MAX':
+            continue
+
+        codes[c.value] = c.name
+
+    return codes
+
+
+def generate_keycodes_file(template, codes):
+    '''
+    Generate a new keycodes/evdev file with line containing @evdevkeys@
+    replaced by the full list of known evdev key codes, including our
+    section_header/footer. Expected output:
+
+    ::
+
+    // $section_header
+    <I$keycode> = <$keycode + 8> // #define $kernel_name
+    ...
+    // $section_footer
+
+    '''
+    output = []
+    for line in template.readlines():
+        if replacement_marker not in line:
+            output.append(line)
+            continue
+
+        output.append(f'\t// {section_header}\n')
+
+        warned = False
+        for code, name in codes.items():
+            xkeycode = code + 8
+
+            if xkeycode > 255 and not warned:
+                warned = True
+                output.append('\n')
+                output.append('\t// Key codes below cannot be used in X\n')
+                output.append('\n')
+
+            # Special keys that need a comment
+            special_keys = {
+                211: 'conflicts with AB11',
+            }
+
+            comment = special_keys.get(xkeycode, '')
+            if comment:
+                comment = f' {comment}'
+
+            output.append(f'\t<I{xkeycode}> = {xkeycode};\t// #define {name:23s} {code}{comment}\n')
+        output.append(f'\t// {section_footer}\n')
+
+    return output
+
+
+def extract_generated_keycodes(oldfile):
+    in_generated_section = False
+    pattern = re.compile('.*<I([0-9]*)>.*')
+
+    for line in oldfile:
+        if section_header in line:
+            in_generated_section = True
+            continue
+        elif section_footer in line:
+            return
+        elif in_generated_section:
+            match = pattern.match(line)
+            if match:
+                yield int(match[1])
+
+
+def compare_with(codes, oldfile):
+    '''
+    Extract the <I123> keycodes from between the section_header/footer of
+    oldfile and return a list of keycodes that are in codes but not in
+    oldfile.
+    '''
+    old_keycodes = extract_generated_keycodes(oldfile)
+    keycodes = [c + 8 for c in codes]  # X keycode offset
+
+    # This does not detect keycodes in old_keycode but not in the new
+    # generated list - should never happen anyway.
+    return sorted(set(keycodes).difference(old_keycodes))
+
+
+def log_msg(msg):
+    print(msg, file=sys.stderr)
+
+
+def main():
+    parser = argparse.ArgumentParser(description='Generate the evdev keycode lists.')
+    parser.add_argument('--template', type=argparse.FileType('r'),
+                        default=open('keycodes/evdev.in'),
+                        help='The template file, usually keycodes/evdev.in')
+    parser.add_argument('--output', type=str, default=None, required=True,
+                        help='The file to be written to')
+    parser.add_argument('--compare-with', type=argparse.FileType('r'),
+                        help='Compare generated output with the given file')
+    parser.add_argument('--verbose', action=argparse.BooleanOptionalAction,
+                        help='Print verbose output to stderr')
+    ns = parser.parse_args()
+
+    codes = evdev_codes()
+    rc = 0
+    if ns.verbose:
+        kmin, kmax = min(codes.keys()), max(codes.keys())
+        log_msg(f'evdev keycode range: {kmin} ({kmin:#x}) → {kmax} ({kmax:#x})')
+
+    # We compare before writing so we can use the same filename for
+    # --compare-with and --output. That's also why --output has to be type
+    # str instead of FileType('w').
+    if ns.compare_with:
+        diff = compare_with(codes, ns.compare_with)
+        if diff:
+            rc = 1
+            if ns.verbose:
+                log_msg(f'File {ns.compare_with.name} is out of date, missing keycodes:')
+                for k in diff:
+                    name = codes[k - 8]  # remove the X offset
+                    log_msg(f'  <I{k}> // #define {name}')
+
+    with contextlib.ExitStack() as stack:
+        if ns.output == '-':
+            fd = sys.stdout
+        else:
+            fd = stack.enter_context(open(ns.output, 'w'))
+        output = generate_keycodes_file(ns.template, codes)
+        fd.write(''.join(output))
+
+    sys.exit(rc)
+
+
+if __name__ == '__main__':
+    main()