1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/python/mozbuild/mozpack/executables.py Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,121 @@
1.4 +# This Source Code Form is subject to the terms of the Mozilla Public
1.5 +# License, v. 2.0. If a copy of the MPL was not distributed with this
1.6 +# file, You can obtain one at http://mozilla.org/MPL/2.0/.
1.7 +
1.8 +import os
1.9 +import struct
1.10 +import subprocess
1.11 +from mozpack.errors import errors
1.12 +
1.13 +MACHO_SIGNATURES = [
1.14 + 0xfeedface, # mach-o 32-bits big endian
1.15 + 0xcefaedfe, # mach-o 32-bits little endian
1.16 + 0xfeedfacf, # mach-o 64-bits big endian
1.17 + 0xcffaedfe, # mach-o 64-bits little endian
1.18 +]
1.19 +
1.20 +FAT_SIGNATURE = 0xcafebabe # mach-o FAT binary
1.21 +
1.22 +ELF_SIGNATURE = 0x7f454c46 # Elf binary
1.23 +
1.24 +UNKNOWN = 0
1.25 +MACHO = 1
1.26 +ELF = 2
1.27 +
1.28 +def get_type(path):
1.29 + '''
1.30 + Check the signature of the give file and returns what kind of executable
1.31 + matches.
1.32 + '''
1.33 + with open(path, 'rb') as f:
1.34 + signature = f.read(4)
1.35 + if len(signature) < 4:
1.36 + return UNKNOWN
1.37 + signature = struct.unpack('>L', signature)[0]
1.38 + if signature == ELF_SIGNATURE:
1.39 + return ELF
1.40 + if signature in MACHO_SIGNATURES:
1.41 + return MACHO
1.42 + if signature != FAT_SIGNATURE:
1.43 + return UNKNOWN
1.44 + # We have to sanity check the second four bytes, because Java class
1.45 + # files use the same magic number as Mach-O fat binaries.
1.46 + # This logic is adapted from file(1), which says that Mach-O uses
1.47 + # these bytes to count the number of architectures within, while
1.48 + # Java uses it for a version number. Conveniently, there are only
1.49 + # 18 labelled Mach-O architectures, and Java's first released
1.50 + # class format used the version 43.0.
1.51 + num = f.read(4)
1.52 + if len(num) < 4:
1.53 + return UNKNOWN
1.54 + num = struct.unpack('>L', num)[0]
1.55 + if num < 20:
1.56 + return MACHO
1.57 + return UNKNOWN
1.58 +
1.59 +
1.60 +def is_executable(path):
1.61 + '''
1.62 + Return whether a given file path points to an executable or a library,
1.63 + where an executable or library is identified by:
1.64 + - the file extension on OS/2 and WINNT
1.65 + - the file signature on OS/X and ELF systems (GNU/Linux, Android, BSD,
1.66 + Solaris)
1.67 +
1.68 + As this function is intended for use to choose between the ExecutableFile
1.69 + and File classes in FileFinder, and choosing ExecutableFile only matters
1.70 + on OS/2, OS/X, ELF and WINNT (in GCC build) systems, we don't bother
1.71 + detecting other kind of executables.
1.72 + '''
1.73 + from buildconfig import substs
1.74 + if not os.path.exists(path):
1.75 + return False
1.76 +
1.77 + if substs['OS_ARCH'] == 'WINNT':
1.78 + return path.lower().endswith((substs['DLL_SUFFIX'],
1.79 + substs['BIN_SUFFIX']))
1.80 +
1.81 + return get_type(path) != UNKNOWN
1.82 +
1.83 +
1.84 +def may_strip(path):
1.85 + '''
1.86 + Return whether strip() should be called
1.87 + '''
1.88 + from buildconfig import substs
1.89 + return not substs['PKG_SKIP_STRIP']
1.90 +
1.91 +
1.92 +def strip(path):
1.93 + '''
1.94 + Execute the STRIP command with STRIP_FLAGS on the given path.
1.95 + '''
1.96 + from buildconfig import substs
1.97 + strip = substs['STRIP']
1.98 + flags = substs['STRIP_FLAGS'].split() if 'STRIP_FLAGS' in substs else []
1.99 + cmd = [strip] + flags + [path]
1.100 + if subprocess.call(cmd) != 0:
1.101 + errors.fatal('Error executing ' + ' '.join(cmd))
1.102 +
1.103 +
1.104 +def may_elfhack(path):
1.105 + '''
1.106 + Return whether elfhack() should be called
1.107 + '''
1.108 + # elfhack only supports libraries. We should check the ELF header for
1.109 + # the right flag, but checking the file extension works too.
1.110 + from buildconfig import substs
1.111 + return 'USE_ELF_HACK' in substs and substs['USE_ELF_HACK'] and \
1.112 + path.endswith(substs['DLL_SUFFIX'])
1.113 +
1.114 +
1.115 +def elfhack(path):
1.116 + '''
1.117 + Execute the elfhack command on the given path.
1.118 + '''
1.119 + from buildconfig import topobjdir
1.120 + cmd = [os.path.join(topobjdir, 'build/unix/elfhack/elfhack'), path]
1.121 + if 'ELF_HACK_FLAGS' in os.environ:
1.122 + cmd[1:0] = os.environ['ELF_HACK_FLAGS'].split()
1.123 + if subprocess.call(cmd) != 0:
1.124 + errors.fatal('Error executing ' + ' '.join(cmd))
