diff --git a/contrib/devtools/README.md b/contrib/devtools/README.md index 15ee8a395..7ac8aa39d 100644 --- a/contrib/devtools/README.md +++ b/contrib/devtools/README.md @@ -194,3 +194,14 @@ It will do the following automatically: - add missing translations to the build system (TODO) See doc/translation-process.md for more information. + +circular-dependencies.py +======================== + +Run this script from the root of the source tree (`src/`) to find circular dependencies in the source code. +This looks only at which files include other files, treating the `.cpp` and `.h` file as one unit. + +Example usage: + + cd .../src + ../contrib/devtools/circular-dependencies.py {*,*/*,*/*/*}.{h,cpp} diff --git a/contrib/devtools/circular-dependencies.py b/contrib/devtools/circular-dependencies.py new file mode 100755 index 000000000..d544d5c37 --- /dev/null +++ b/contrib/devtools/circular-dependencies.py @@ -0,0 +1,79 @@ +#!/usr/bin/env python3 + +import sys +import re + +MAPPING = { + 'core_read.cpp': 'core_io.cpp', + 'core_write.cpp': 'core_io.cpp', +} + +def module_name(path): + if path in MAPPING: + path = MAPPING[path] + if path.endswith(".h"): + return path[:-2] + if path.endswith(".c"): + return path[:-2] + if path.endswith(".cpp"): + return path[:-4] + return None + +files = dict() +deps = dict() + +RE = re.compile("^#include <(.*)>") + +# Iterate over files, and create list of modules +for arg in sys.argv[1:]: + module = module_name(arg) + if module is None: + print("Ignoring file %s (does not constitute module)\n" % arg) + else: + files[arg] = module + deps[module] = set() + +# Iterate again, and build list of direct dependencies for each module +# TODO: implement support for multiple include directories +for arg in sorted(files.keys()): + module = files[arg] + with open(arg, 'r') as f: + for line in f: + match = RE.match(line) + if match: + include = match.group(1) + included_module = module_name(include) + if included_module is not None and included_module in deps and included_module != module: + deps[module].add(included_module) + +# Loop to find the shortest (remaining) circular dependency +have_cycle = False +while True: + shortest_cycle = None + for module in sorted(deps.keys()): + # Build the transitive closure of dependencies of module + closure = dict() + for dep in deps[module]: + closure[dep] = [] + while True: + old_size = len(closure) + old_closure_keys = sorted(closure.keys()) + for src in old_closure_keys: + for dep in deps[src]: + if dep not in closure: + closure[dep] = closure[src] + [src] + if len(closure) == old_size: + break + # If module is in its own transitive closure, it's a circular dependency; check if it is the shortest + if module in closure and (shortest_cycle is None or len(closure[module]) + 1 < len(shortest_cycle)): + shortest_cycle = [module] + closure[module] + if shortest_cycle is None: + break + # We have the shortest circular dependency; report it + module = shortest_cycle[0] + print("Circular dependency: %s" % (" -> ".join(shortest_cycle + [module]))) + # And then break the dependency to avoid repeating in other cycles + deps[shortest_cycle[-1]] = deps[shortest_cycle[-1]] - set([module]) + have_cycle = True + +sys.exit(1 if have_cycle else 0)