Package: libmagic-mgc Version: 1:5.30-1 Tags: patch File: /usr/share/file/magic.mgc Severity: wishlist
$ file /usr/include/c++/6/* /usr/include/c++/6/algorithm: C source, ASCII text /usr/include/c++/6/array: C source, ASCII text /usr/include/c++/6/atomic: C source, ASCII text /usr/include/c++/6/backward: directory /usr/include/c++/6/bits: directory /usr/include/c++/6/bitset: C source, ASCII text /usr/include/c++/6/cassert: C source, ASCII text /usr/include/c++/6/ccomplex: C source, ASCII text /usr/include/c++/6/cctype: C source, ASCII text /usr/include/c++/6/cerrno: C source, ASCII text /usr/include/c++/6/cfenv: C source, ASCII text /usr/include/c++/6/cfloat: C source, ASCII text /usr/include/c++/6/chrono: C source, ASCII text /usr/include/c++/6/cinttypes: C source, ASCII text /usr/include/c++/6/ciso646: C source, ASCII text /usr/include/c++/6/climits: C source, ASCII text /usr/include/c++/6/clocale: C source, ASCII text /usr/include/c++/6/cmath: C source, ASCII text /usr/include/c++/6/codecvt: C source, ASCII text /usr/include/c++/6/complex: C source, ASCII text /usr/include/c++/6/complex.h: C source, ASCII text /usr/include/c++/6/condition_variable: C source, ASCII text /usr/include/c++/6/csetjmp: C source, ASCII text /usr/include/c++/6/csignal: C source, ASCII text /usr/include/c++/6/cstdalign: ASCII text /usr/include/c++/6/cstdarg: C source, ASCII text /usr/include/c++/6/cstdbool: ASCII text /usr/include/c++/6/cstddef: C source, ASCII text /usr/include/c++/6/cstdint: C source, ASCII text /usr/include/c++/6/cstdio: C source, ASCII text /usr/include/c++/6/cstdlib: C source, ASCII text /usr/include/c++/6/cstring: C source, ASCII text /usr/include/c++/6/ctgmath: C source, ASCII text /usr/include/c++/6/ctime: C source, ASCII text /usr/include/c++/6/cuchar: C source, ASCII text /usr/include/c++/6/cwchar: C source, ASCII text /usr/include/c++/6/cwctype: C source, ASCII text /usr/include/c++/6/cxxabi.h: C source, ASCII text /usr/include/c++/6/debug: directory /usr/include/c++/6/decimal: directory /usr/include/c++/6/deque: C source, ASCII text /usr/include/c++/6/exception: C source, ASCII text /usr/include/c++/6/experimental: directory /usr/include/c++/6/ext: directory /usr/include/c++/6/fenv.h: C source, ASCII text /usr/include/c++/6/forward_list: C source, ASCII text /usr/include/c++/6/fstream: C source, ASCII text /usr/include/c++/6/functional: C source, ASCII text /usr/include/c++/6/future: C source, UTF-8 Unicode text /usr/include/c++/6/initializer_list: C source, ASCII text /usr/include/c++/6/iomanip: C source, ASCII text /usr/include/c++/6/ios: C source, ASCII text /usr/include/c++/6/iosfwd: C source, ASCII text /usr/include/c++/6/iostream: C source, ASCII text /usr/include/c++/6/istream: C source, ASCII text /usr/include/c++/6/iterator: C source, ASCII text /usr/include/c++/6/limits: C source, ASCII text /usr/include/c++/6/list: C source, ASCII text /usr/include/c++/6/locale: C source, ASCII text /usr/include/c++/6/map: C source, ASCII text /usr/include/c++/6/math.h: ASCII text /usr/include/c++/6/memory: C++ source, ASCII text /usr/include/c++/6/mutex: C source, ASCII text /usr/include/c++/6/new: C source, ASCII text /usr/include/c++/6/numeric: C source, ASCII text /usr/include/c++/6/ostream: C source, ASCII text /usr/include/c++/6/parallel: directory /usr/include/c++/6/profile: directory /usr/include/c++/6/queue: C source, ASCII text /usr/include/c++/6/random: C source, ASCII text /usr/include/c++/6/ratio: C source, ASCII text /usr/include/c++/6/regex: C source, ASCII text /usr/include/c++/6/scoped_allocator: C source, ASCII text /usr/include/c++/6/set: C source, ASCII text /usr/include/c++/6/shared_mutex: C source, ASCII text /usr/include/c++/6/sstream: C source, ASCII text /usr/include/c++/6/stack: C source, ASCII text /usr/include/c++/6/stdexcept: C source, ASCII text /usr/include/c++/6/stdlib.h: ASCII text /usr/include/c++/6/streambuf: C source, ASCII text /usr/include/c++/6/string: C source, ASCII text /usr/include/c++/6/sun: directory /usr/include/c++/6/system_error: C source, ASCII text /usr/include/c++/6/tgmath.h: C source, ASCII text /usr/include/c++/6/thread: C source, ASCII text /usr/include/c++/6/tr1: directory /usr/include/c++/6/tr2: directory /usr/include/c++/6/tuple: C source, ASCII text /usr/include/c++/6/type_traits: C source, ASCII text /usr/include/c++/6/typeindex: C source, ASCII text /usr/include/c++/6/typeinfo: C source, ASCII text /usr/include/c++/6/unordered_map: C source, ASCII text /usr/include/c++/6/unordered_set: C source, ASCII text /usr/include/c++/6/utility: C source, ASCII text /usr/include/c++/6/valarray: C source, ASCII text /usr/include/c++/6/vector: C source, ASCII text $ It does identify one of those C++ headers as C++ indeed. The issue here seems to be that a lot of these headers put stuff inside a namespace and indent it. The patterns from file generally search for unindented keywords though. Another issue seems to be the common pattern of adding a line break after a template specification. After applying the attached patch detection is slightly improved: $ file -m ./magic.mgc /usr/include/c++/6/* /usr/include/c++/6/algorithm: C source, ASCII text /usr/include/c++/6/array: C source, ASCII text /usr/include/c++/6/atomic: C++ source, ASCII text /usr/include/c++/6/backward: directory /usr/include/c++/6/bits: directory /usr/include/c++/6/bitset: C source, ASCII text /usr/include/c++/6/cassert: C source, ASCII text /usr/include/c++/6/ccomplex: C source, ASCII text /usr/include/c++/6/cctype: C source, ASCII text /usr/include/c++/6/cerrno: C source, ASCII text /usr/include/c++/6/cfenv: C source, ASCII text /usr/include/c++/6/cfloat: C source, ASCII text /usr/include/c++/6/chrono: C++ source, ASCII text /usr/include/c++/6/cinttypes: C source, ASCII text /usr/include/c++/6/ciso646: C source, ASCII text /usr/include/c++/6/climits: C source, ASCII text /usr/include/c++/6/clocale: C source, ASCII text /usr/include/c++/6/cmath: C source, ASCII text /usr/include/c++/6/codecvt: C++ source, ASCII text /usr/include/c++/6/complex: C++ source, ASCII text /usr/include/c++/6/complex.h: C source, ASCII text /usr/include/c++/6/condition_variable: C++ source, ASCII text /usr/include/c++/6/csetjmp: C source, ASCII text /usr/include/c++/6/csignal: C source, ASCII text /usr/include/c++/6/cstdalign: ASCII text /usr/include/c++/6/cstdarg: C source, ASCII text /usr/include/c++/6/cstdbool: ASCII text /usr/include/c++/6/cstddef: C source, ASCII text /usr/include/c++/6/cstdint: C source, ASCII text /usr/include/c++/6/cstdio: C source, ASCII text /usr/include/c++/6/cstdlib: C source, ASCII text /usr/include/c++/6/cstring: C source, ASCII text /usr/include/c++/6/ctgmath: C source, ASCII text /usr/include/c++/6/ctime: C source, ASCII text /usr/include/c++/6/cuchar: C source, ASCII text /usr/include/c++/6/cwchar: C source, ASCII text /usr/include/c++/6/cwctype: C source, ASCII text /usr/include/c++/6/cxxabi.h: C++ source, ASCII text /usr/include/c++/6/debug: directory /usr/include/c++/6/decimal: directory /usr/include/c++/6/deque: C source, ASCII text /usr/include/c++/6/exception: C++ source, ASCII text /usr/include/c++/6/experimental: directory /usr/include/c++/6/ext: directory /usr/include/c++/6/fenv.h: C source, ASCII text /usr/include/c++/6/forward_list: C source, ASCII text /usr/include/c++/6/fstream: C++ source, ASCII text /usr/include/c++/6/functional: C source, ASCII text /usr/include/c++/6/future: C++ source, UTF-8 Unicode text /usr/include/c++/6/initializer_list: C++ source, ASCII text /usr/include/c++/6/iomanip: C source, ASCII text /usr/include/c++/6/ios: C source, ASCII text /usr/include/c++/6/iosfwd: C source, ASCII text /usr/include/c++/6/iostream: C source, ASCII text /usr/include/c++/6/istream: C++ source, ASCII text /usr/include/c++/6/iterator: C source, ASCII text /usr/include/c++/6/limits: C source, ASCII text /usr/include/c++/6/list: C source, ASCII text /usr/include/c++/6/locale: C source, ASCII text /usr/include/c++/6/map: C source, ASCII text /usr/include/c++/6/math.h: ASCII text /usr/include/c++/6/memory: C++ source, ASCII text /usr/include/c++/6/mutex: C++ source, ASCII text /usr/include/c++/6/new: C++ source, ASCII text /usr/include/c++/6/numeric: C source, ASCII text /usr/include/c++/6/ostream: C++ source, ASCII text /usr/include/c++/6/parallel: directory /usr/include/c++/6/profile: directory /usr/include/c++/6/queue: C source, ASCII text /usr/include/c++/6/random: C source, ASCII text /usr/include/c++/6/ratio: C++ source, ASCII text /usr/include/c++/6/regex: C source, ASCII text /usr/include/c++/6/scoped_allocator: C++ source, ASCII text /usr/include/c++/6/set: C source, ASCII text /usr/include/c++/6/shared_mutex: C++ source, ASCII text /usr/include/c++/6/sstream: C++ source, ASCII text /usr/include/c++/6/stack: C source, ASCII text /usr/include/c++/6/stdexcept: C++ source, ASCII text /usr/include/c++/6/stdlib.h: ASCII text /usr/include/c++/6/streambuf: C++ source, ASCII text /usr/include/c++/6/string: C source, ASCII text /usr/include/c++/6/sun: directory /usr/include/c++/6/system_error: C++ source, ASCII text /usr/include/c++/6/tgmath.h: C source, ASCII text /usr/include/c++/6/thread: C++ source, ASCII text /usr/include/c++/6/tr1: directory /usr/include/c++/6/tr2: directory /usr/include/c++/6/tuple: C source, ASCII text /usr/include/c++/6/type_traits: C source, ASCII text /usr/include/c++/6/typeindex: C++ source, ASCII text /usr/include/c++/6/typeinfo: C++ source, ASCII text /usr/include/c++/6/unordered_map: C source, ASCII text /usr/include/c++/6/unordered_set: C source, ASCII text /usr/include/c++/6/utility: C++ source, ASCII text /usr/include/c++/6/valarray: C++ source, ASCII text /usr/include/c++/6/vector: C source, ASCII text $ Most of the undetected headers only #include stuff or have a very long comment blurb. I'm less sure about how much the attached patch breaks in terms of misdetections of other files and in terms of performance. Allowing EOL instead of space should not hurt much, but allowing spaces at the start of lines might regress. In any case, I ask for improving C++ vs. C detection and propose the attached patch as a basis. A lot of regex patterns end with a plus sign. Removing those plus signs changes the match region, but it never changes whether a regex matches. Thus they can safely be removed and that might improve performance. Helmut
Index: file-5.30/magic/Magdir/c-lang =================================================================== --- file-5.30.orig/magic/Magdir/c-lang +++ file-5.30/magic/Magdir/c-lang @@ -14,37 +14,37 @@ 0 regex \^#include C source text !:strength +25 !:mime text/x-c -0 regex \^char[\ \t\n]+ C source text +0 regex \^[\ \t]*char[\ \t\n]+ C source text !:mime text/x-c -0 regex \^double[\ \t\n]+ C source text +0 regex \^[\ \t]*double[\ \t\n]+ C source text !:mime text/x-c -0 regex \^extern[\ \t\n]+ C source text +0 regex \^[\ \t]*extern[\ \t\n]+ C source text !:mime text/x-c -0 regex \^float[\ \t\n]+ C source text +0 regex \^[\ \t]*float[\ \t\n]+ C source text !:mime text/x-c -0 regex \^struct[\ \t\n]+ C source text +0 regex \^[\ \t]*struct[\ \t\n]+ C source text !:mime text/x-c -0 regex \^union[\ \t\n]+ C source text +0 regex \^[\ \t]*union[\ \t\n]+ C source text !:mime text/x-c 0 search/8192 main( C source text !:mime text/x-c # C++ # The strength of these rules is increased so they beat the C rules above -0 regex \^template[\ \t]+<.*>[\ \t\n]+ C++ source text +0 regex \^[\ \t]*template[\ \t]+<.*>([\ \t\n]|$) C++ source text !:strength + 30 !:mime text/x-c++ -0 regex \^virtual[\ \t\n]+ C++ source text +0 regex \^[\ \t]*virtual[\ \t\n]+ C++ source text !:strength + 30 !:mime text/x-c++ -0 regex \^class[\ \t\n]+ C++ source text +0 regex \^[\ \t]*class[\ \t\n]+ C++ source text # But class is reduced to avoid beating php (Jens Schleusener) !:strength + 13 !:mime text/x-c++ -0 regex \^public: C++ source text +0 regex \^[\ \t]*public: C++ source text !:strength + 30 !:mime text/x-c++ -0 regex \^private: C++ source text +0 regex \^[\ \t]*private: C++ source text !:strength + 30 !:mime text/x-c++
