1 files changed, 137 insertions, 0 deletions

diff --git a/lib/python/qmk/compilation_database.py b/lib/python/qmk/compilation_database.py
new file mode 100755
index 0000000000..4c88dadbdd
--- /dev/null
+++ b/lib/python/qmk/compilation_database.py
@@ -0,0 +1,137 @@
+"""Creates a compilation database for the given keyboard build.
+"""
+
+import json
+import os
+import re
+import shlex
+import shutil
+from functools import lru_cache
+from pathlib import Path
+from typing import Dict, Iterator, List
+
+from milc import cli
+
+from qmk.commands import find_make
+from qmk.constants import QMK_FIRMWARE
+
+
+@lru_cache(maxsize=10)
+def system_libs(binary: str) -> List[Path]:
+    """Find the system include directory that the given build tool uses.
+    """
+    cli.log.debug("searching for system library directory for binary: %s", binary)
+
+    # Actually query xxxxxx-gcc to find its include paths.
+    if binary.endswith("gcc") or binary.endswith("g++"):
+        # (TODO): Remove 'stdin' once 'input' no longer causes issues under MSYS
+        result = cli.run([binary, '-E', '-Wp,-v', '-'], capture_output=True, check=True, stdin=None, input='\n')
+        paths = []
+        for line in result.stderr.splitlines():
+            if line.startswith(" "):
+                paths.append(Path(line.strip()).resolve())
+        return paths
+
+    return list(Path(binary).resolve().parent.parent.glob("*/include")) if binary else []
+
+
+@lru_cache(maxsize=10)
+def cpu_defines(binary: str, compiler_args: str) -> List[str]:
+    cli.log.debug("gathering definitions for compilation: %s %s", binary, compiler_args)
+    if binary.endswith("gcc") or binary.endswith("g++"):
+        invocation = [binary, '-dM', '-E']
+        if binary.endswith("gcc"):
+            invocation.extend(['-x', 'c'])
+        elif binary.endswith("g++"):
+            invocation.extend(['-x', 'c++'])
+        compiler_args = shlex.split(compiler_args)
+        invocation.extend(compiler_args)
+        invocation.append('-')
+        result = cli.run(invocation, capture_output=True, check=True, stdin=None, input='\n')
+        define_args = []
+        for line in result.stdout.splitlines():
+            line_args = line.split(' ', 2)
+            if len(line_args) == 3 and line_args[0] == '#define':
+                define_args.append(f'-D{line_args[1]}={line_args[2]}')
+            elif len(line_args) == 2 and line_args[0] == '#define':
+                define_args.append(f'-D{line_args[1]}')
+        return list(sorted(set(define_args)))
+    return []
+
+
+file_re = re.compile(r'printf "Compiling: ([^"]+)')
+cmd_re = re.compile(r'LOG=\$\((.+?)&&')
+
+
+def parse_make_n(f: Iterator[str]) -> List[Dict[str, str]]:
+    """parse the output of `make -n <target>`
+
+    This function makes many assumptions about the format of your build log.
+    This happens to work right now for qmk.
+    """
+
+    state = 'start'
+    this_file = None
+    records = []
+    for line in f:
+        if state == 'start':
+            m = file_re.search(line)
+            if m:
+                this_file = m.group(1)
+                state = 'cmd'
+
+        if state == 'cmd':
+            assert this_file
+            m = cmd_re.search(line)
+            if m:
+                # we have a hit!
+                this_cmd = m.group(1)
+                args = shlex.split(this_cmd)
+                binary = shutil.which(args[0])
+                compiler_args = set(filter(lambda x: x.startswith('-m') or x.startswith('-f'), args))
+                for s in system_libs(binary):
+                    args += ['-isystem', '%s' % s]
+                args.extend(cpu_defines(binary, ' '.join(shlex.quote(s) for s in compiler_args)))
+                new_cmd = ' '.join(shlex.quote(s) for s in args)
+                records.append({"directory": str(QMK_FIRMWARE.resolve()), "command": new_cmd, "file": this_file})
+                state = 'start'
+
+    return records
+
+
+def write_compilation_database(keyboard: str = None, keymap: str = None, output_path: Path = QMK_FIRMWARE / 'compile_commands.json', skip_clean: bool = False, command: List[str] = None, **env_vars) -> bool:
+    # Generate the make command for a specific keyboard/keymap.
+    if not command:
+        from qmk.build_targets import KeyboardKeymapBuildTarget  # Lazy load due to circular references
+        target = KeyboardKeymapBuildTarget(keyboard, keymap)
+        command = target.compile_command(dry_run=True, **env_vars)
+
+    if not command:
+        cli.log.error('You must supply both `--keyboard` and `--keymap`, or be in a directory for a keyboard or keymap.')
+        cli.echo('usage: qmk generate-compilation-database [-kb KEYBOARD] [-km KEYMAP]')
+        return False
+
+    # remove any environment variable overrides which could trip us up
+    env = os.environ.copy()
+    env.pop("MAKEFLAGS", None)
+
+    # re-use same executable as the main make invocation (might be gmake)
+    if not skip_clean:
+        clean_command = [find_make(), "clean"]
+        cli.log.info('Making clean with {fg_cyan}%s', ' '.join(clean_command))
+        cli.run(clean_command, capture_output=False, check=True, env=env)
+
+    cli.log.info('Gathering build instructions from {fg_cyan}%s', ' '.join(command))
+
+    result = cli.run(command, capture_output=True, check=True, env=env)
+    db = parse_make_n(result.stdout.splitlines())
+    if not db:
+        cli.log.error("Failed to parse output from make output:\n%s", result.stdout)
+        return False
+
+    cli.log.info("Found %s compile commands", len(db))
+
+    cli.log.info(f"Writing build database to {output_path}")
+    output_path.write_text(json.dumps(db, indent=4))
+
+    return True