| Austin Schuh | 0cbef62 | 2015-09-06 17:34:52 -0700 | [diff] [blame] | 1 | Goal: |
| 2 | ----- |
| 3 | CppClean attempts to find problems in C++ source that slow development |
| 4 | in large code bases, for example various forms of unused code. |
| 5 | Unused code can be unused functions, methods, data members, types, etc |
| 6 | to unnecessary #include directives. Unnecessary #includes can cause |
| 7 | considerable extra compiles increasing the edit-compile-run cycle. |
| 8 | |
| 9 | The project home page is: http://code.google.com/p/cppclean/ |
| 10 | |
| 11 | |
| 12 | Features: |
| 13 | --------- |
| 14 | * Find and print C++ language constructs: classes, methods, functions, etc. |
| 15 | * Find classes with virtual methods, no virtual destructor, and no bases |
| 16 | * Find global/static data that are potential problems when using threads |
| 17 | * Unnecessary forward class declarations |
| 18 | * Unnecessary function declarations |
| 19 | * Undeclared function definitions |
| 20 | * (planned) Find unnecessary header files #included |
| 21 | - No direct reference to anything in the header |
| 22 | - Header is unnecessary if classes were forward declared instead |
| 23 | * (planned) Source files that reference headers not directly #included, |
| 24 | ie, files that rely on a transitive #include from another header |
| 25 | * (planned) Unused members (private, protected, & public) methods and data |
| 26 | * (planned) Store AST in a SQL database so relationships can be queried |
| 27 | |
| 28 | AST is Abstract Syntax Tree, a representation of parsed source code. |
| 29 | http://en.wikipedia.org/wiki/Abstract_syntax_tree |
| 30 | |
| 31 | |
| 32 | System Requirements: |
| 33 | -------------------- |
| 34 | * Python 2.4 or later (2.3 probably works too) |
| 35 | * Works on Windows (untested), Mac OS X, and Unix |
| 36 | |
| 37 | |
| 38 | How to Run: |
| 39 | ----------- |
| 40 | For all examples, it is assumed that cppclean resides in a directory called |
| 41 | /cppclean. |
| 42 | |
| 43 | To print warnings for classes with virtual methods, no virtual destructor and |
| 44 | no base classes: |
| 45 | |
| 46 | /cppclean/run.sh nonvirtual_dtors.py file1.h file2.h file3.cc ... |
| 47 | |
| 48 | To print all the functions defined in header file(s): |
| 49 | |
| 50 | /cppclean/run.sh functions.py file1.h file2.h ... |
| 51 | |
| 52 | All the commands take multiple files on the command line. Other programs |
| 53 | include: find_warnings, headers, methods, and types. Some other programs |
| 54 | are available, but used primarily for debugging. |
| 55 | |
| 56 | run.sh is a simple wrapper that sets PYTHONPATH to /cppclean and then |
| 57 | runs the program in /cppclean/cpp/PROGRAM.py. There is currently |
| 58 | no equivalent for Windows. Contributions for a run.bat file |
| 59 | would be greatly appreciated. |
| 60 | |
| 61 | |
| 62 | How to Configure: |
| 63 | ----------------- |
| 64 | You can add a siteheaders.py file in /cppclean/cpp to configure where |
| 65 | to look for other headers (typically -I options passed to a compiler). |
| 66 | Currently two values are supported: _TRANSITIVE and GetIncludeDirs. |
| 67 | _TRANSITIVE should be set to a boolean value (True or False) indicating |
| 68 | whether to transitively process all header files. The default is False. |
| 69 | |
| 70 | GetIncludeDirs is a function that takes a single argument and returns |
| 71 | a sequence of directories to include. This can be a generator or |
| 72 | return a static list. |
| 73 | |
| 74 | def GetIncludeDirs(filename): |
| 75 | return ['/some/path/with/other/headers'] |
| 76 | |
| 77 | # Here is a more complicated example. |
| 78 | def GetIncludeDirs(filename): |
| 79 | yield '/path1' |
| 80 | yield os.path.join('/path2', os.path.dirname(filename)) |
| 81 | yield '/path3' |
| 82 | |
| 83 | |
| 84 | How to Test: |
| 85 | ------------ |
| 86 | For all examples, it is assumed that cppclean resides in a directory called |
| 87 | /cppclean. The tests require |
| 88 | |
| 89 | cd /cppclean |
| 90 | make test |
| 91 | # To generate expected results after a change: |
| 92 | make expected |
| 93 | |
| 94 | |
| 95 | Current Status: |
| 96 | --------------- |
| 97 | The parser works pretty well for header files, parsing about 99% of Google's |
| 98 | header files. Anything which inspects structure of C++ source files should |
| 99 | work reasonably well. Function bodies are not transformed to an AST, |
| 100 | but left as tokens. Much work is still needed on finding unused header files |
| 101 | and storing an AST in a database. |
| 102 | |
| 103 | |
| 104 | Non-goals: |
| 105 | ---------- |
| 106 | * Parsing all valid C++ source |
| 107 | * Handling invalid C++ source gracefully |
| 108 | * Compiling to machine code (or anything beyond an AST) |
| 109 | |
| 110 | |
| 111 | Contact: |
| 112 | -------- |
| 113 | If you used cppclean, I would love to hear about your experiences |
| 114 | cppclean@googlegroups.com. Even if you don't use cppclean, I'd like to |
| 115 | hear from you. :-) (You can contact me directly at: nnorwitz@gmail.com) |