Olivier Deprez | f4ef2d0 | 2021-04-20 13:36:24 +0200 | [diff] [blame] | 1 | """distutils.spawn |
| 2 | |
| 3 | Provides the 'spawn()' function, a front-end to various platform- |
| 4 | specific functions for launching another program in a sub-process. |
| 5 | Also provides the 'find_executable()' to search the path for a given |
| 6 | executable name. |
| 7 | """ |
| 8 | |
| 9 | import sys |
| 10 | import os |
| 11 | import subprocess |
| 12 | |
| 13 | from distutils.errors import DistutilsPlatformError, DistutilsExecError |
| 14 | from distutils.debug import DEBUG |
| 15 | from distutils import log |
| 16 | |
| 17 | |
| 18 | if sys.platform == 'darwin': |
| 19 | _cfg_target = None |
| 20 | _cfg_target_split = None |
| 21 | |
| 22 | |
| 23 | def spawn(cmd, search_path=1, verbose=0, dry_run=0): |
| 24 | """Run another program, specified as a command list 'cmd', in a new process. |
| 25 | |
| 26 | 'cmd' is just the argument list for the new process, ie. |
| 27 | cmd[0] is the program to run and cmd[1:] are the rest of its arguments. |
| 28 | There is no way to run a program with a name different from that of its |
| 29 | executable. |
| 30 | |
| 31 | If 'search_path' is true (the default), the system's executable |
| 32 | search path will be used to find the program; otherwise, cmd[0] |
| 33 | must be the exact path to the executable. If 'dry_run' is true, |
| 34 | the command will not actually be run. |
| 35 | |
| 36 | Raise DistutilsExecError if running the program fails in any way; just |
| 37 | return on success. |
| 38 | """ |
| 39 | # cmd is documented as a list, but just in case some code passes a tuple |
| 40 | # in, protect our %-formatting code against horrible death |
| 41 | cmd = list(cmd) |
| 42 | |
| 43 | log.info(' '.join(cmd)) |
| 44 | if dry_run: |
| 45 | return |
| 46 | |
| 47 | if search_path: |
| 48 | executable = find_executable(cmd[0]) |
| 49 | if executable is not None: |
| 50 | cmd[0] = executable |
| 51 | |
| 52 | env = None |
| 53 | if sys.platform == 'darwin': |
| 54 | global _cfg_target, _cfg_target_split |
| 55 | if _cfg_target is None: |
| 56 | from distutils import sysconfig |
| 57 | _cfg_target = str(sysconfig.get_config_var( |
| 58 | 'MACOSX_DEPLOYMENT_TARGET') or '') |
| 59 | if _cfg_target: |
| 60 | _cfg_target_split = [int(x) for x in _cfg_target.split('.')] |
| 61 | if _cfg_target: |
| 62 | # ensure that the deployment target of build process is not less |
| 63 | # than that used when the interpreter was built. This ensures |
| 64 | # extension modules are built with correct compatibility values |
| 65 | cur_target = os.environ.get('MACOSX_DEPLOYMENT_TARGET', _cfg_target) |
| 66 | if _cfg_target_split > [int(x) for x in cur_target.split('.')]: |
| 67 | my_msg = ('$MACOSX_DEPLOYMENT_TARGET mismatch: ' |
| 68 | 'now "%s" but "%s" during configure' |
| 69 | % (cur_target, _cfg_target)) |
| 70 | raise DistutilsPlatformError(my_msg) |
| 71 | env = dict(os.environ, |
| 72 | MACOSX_DEPLOYMENT_TARGET=cur_target) |
| 73 | |
| 74 | try: |
| 75 | proc = subprocess.Popen(cmd, env=env) |
| 76 | proc.wait() |
| 77 | exitcode = proc.returncode |
| 78 | except OSError as exc: |
| 79 | if not DEBUG: |
| 80 | cmd = cmd[0] |
| 81 | raise DistutilsExecError( |
| 82 | "command %r failed: %s" % (cmd, exc.args[-1])) from exc |
| 83 | |
| 84 | if exitcode: |
| 85 | if not DEBUG: |
| 86 | cmd = cmd[0] |
| 87 | raise DistutilsExecError( |
| 88 | "command %r failed with exit code %s" % (cmd, exitcode)) |
| 89 | |
| 90 | |
| 91 | def find_executable(executable, path=None): |
| 92 | """Tries to find 'executable' in the directories listed in 'path'. |
| 93 | |
| 94 | A string listing directories separated by 'os.pathsep'; defaults to |
| 95 | os.environ['PATH']. Returns the complete filename or None if not found. |
| 96 | """ |
| 97 | _, ext = os.path.splitext(executable) |
| 98 | if (sys.platform == 'win32') and (ext != '.exe'): |
| 99 | executable = executable + '.exe' |
| 100 | |
| 101 | if os.path.isfile(executable): |
| 102 | return executable |
| 103 | |
| 104 | if path is None: |
| 105 | path = os.environ.get('PATH', None) |
| 106 | if path is None: |
| 107 | try: |
| 108 | path = os.confstr("CS_PATH") |
| 109 | except (AttributeError, ValueError): |
| 110 | # os.confstr() or CS_PATH is not available |
| 111 | path = os.defpath |
| 112 | # bpo-35755: Don't use os.defpath if the PATH environment variable is |
| 113 | # set to an empty string |
| 114 | |
| 115 | # PATH='' doesn't match, whereas PATH=':' looks in the current directory |
| 116 | if not path: |
| 117 | return None |
| 118 | |
| 119 | paths = path.split(os.pathsep) |
| 120 | for p in paths: |
| 121 | f = os.path.join(p, executable) |
| 122 | if os.path.isfile(f): |
| 123 | # the file exists, we have a shot at spawn working |
| 124 | return f |
| 125 | return None |