diff options
Diffstat (limited to 'lib/spack/external/py/_io/capture.py')
| -rw-r--r-- | lib/spack/external/py/_io/capture.py | 371 |
1 files changed, 371 insertions, 0 deletions
diff --git a/lib/spack/external/py/_io/capture.py b/lib/spack/external/py/_io/capture.py new file mode 100644 index 0000000000..bc157ed978 --- /dev/null +++ b/lib/spack/external/py/_io/capture.py @@ -0,0 +1,371 @@ +import os +import sys +import py +import tempfile + +try: + from io import StringIO +except ImportError: + from StringIO import StringIO + +if sys.version_info < (3,0): + class TextIO(StringIO): + def write(self, data): + if not isinstance(data, unicode): + data = unicode(data, getattr(self, '_encoding', 'UTF-8'), 'replace') + StringIO.write(self, data) +else: + TextIO = StringIO + +try: + from io import BytesIO +except ImportError: + class BytesIO(StringIO): + def write(self, data): + if isinstance(data, unicode): + raise TypeError("not a byte value: %r" %(data,)) + StringIO.write(self, data) + +patchsysdict = {0: 'stdin', 1: 'stdout', 2: 'stderr'} + +class FDCapture: + """ Capture IO to/from a given os-level filedescriptor. """ + + def __init__(self, targetfd, tmpfile=None, now=True, patchsys=False): + """ save targetfd descriptor, and open a new + temporary file there. If no tmpfile is + specified a tempfile.Tempfile() will be opened + in text mode. + """ + self.targetfd = targetfd + if tmpfile is None and targetfd != 0: + f = tempfile.TemporaryFile('wb+') + tmpfile = dupfile(f, encoding="UTF-8") + f.close() + self.tmpfile = tmpfile + self._savefd = os.dup(self.targetfd) + if patchsys: + self._oldsys = getattr(sys, patchsysdict[targetfd]) + if now: + self.start() + + def start(self): + try: + os.fstat(self._savefd) + except OSError: + raise ValueError("saved filedescriptor not valid, " + "did you call start() twice?") + if self.targetfd == 0 and not self.tmpfile: + fd = os.open(devnullpath, os.O_RDONLY) + os.dup2(fd, 0) + os.close(fd) + if hasattr(self, '_oldsys'): + setattr(sys, patchsysdict[self.targetfd], DontReadFromInput()) + else: + os.dup2(self.tmpfile.fileno(), self.targetfd) + if hasattr(self, '_oldsys'): + setattr(sys, patchsysdict[self.targetfd], self.tmpfile) + + def done(self): + """ unpatch and clean up, returns the self.tmpfile (file object) + """ + os.dup2(self._savefd, self.targetfd) + os.close(self._savefd) + if self.targetfd != 0: + self.tmpfile.seek(0) + if hasattr(self, '_oldsys'): + setattr(sys, patchsysdict[self.targetfd], self._oldsys) + return self.tmpfile + + def writeorg(self, data): + """ write a string to the original file descriptor + """ + tempfp = tempfile.TemporaryFile() + try: + os.dup2(self._savefd, tempfp.fileno()) + tempfp.write(data) + finally: + tempfp.close() + + +def dupfile(f, mode=None, buffering=0, raising=False, encoding=None): + """ return a new open file object that's a duplicate of f + + mode is duplicated if not given, 'buffering' controls + buffer size (defaulting to no buffering) and 'raising' + defines whether an exception is raised when an incompatible + file object is passed in (if raising is False, the file + object itself will be returned) + """ + try: + fd = f.fileno() + mode = mode or f.mode + except AttributeError: + if raising: + raise + return f + newfd = os.dup(fd) + if sys.version_info >= (3,0): + if encoding is not None: + mode = mode.replace("b", "") + buffering = True + return os.fdopen(newfd, mode, buffering, encoding, closefd=True) + else: + f = os.fdopen(newfd, mode, buffering) + if encoding is not None: + return EncodedFile(f, encoding) + return f + +class EncodedFile(object): + def __init__(self, _stream, encoding): + self._stream = _stream + self.encoding = encoding + + def write(self, obj): + if isinstance(obj, unicode): + obj = obj.encode(self.encoding) + elif isinstance(obj, str): + pass + else: + obj = str(obj) + self._stream.write(obj) + + def writelines(self, linelist): + data = ''.join(linelist) + self.write(data) + + def __getattr__(self, name): + return getattr(self._stream, name) + +class Capture(object): + def call(cls, func, *args, **kwargs): + """ return a (res, out, err) tuple where + out and err represent the output/error output + during function execution. + call the given function with args/kwargs + and capture output/error during its execution. + """ + so = cls() + try: + res = func(*args, **kwargs) + finally: + out, err = so.reset() + return res, out, err + call = classmethod(call) + + def reset(self): + """ reset sys.stdout/stderr and return captured output as strings. """ + if hasattr(self, '_reset'): + raise ValueError("was already reset") + self._reset = True + outfile, errfile = self.done(save=False) + out, err = "", "" + if outfile and not outfile.closed: + out = outfile.read() + outfile.close() + if errfile and errfile != outfile and not errfile.closed: + err = errfile.read() + errfile.close() + return out, err + + def suspend(self): + """ return current snapshot captures, memorize tempfiles. """ + outerr = self.readouterr() + outfile, errfile = self.done() + return outerr + + +class StdCaptureFD(Capture): + """ This class allows to capture writes to FD1 and FD2 + and may connect a NULL file to FD0 (and prevent + reads from sys.stdin). If any of the 0,1,2 file descriptors + is invalid it will not be captured. + """ + def __init__(self, out=True, err=True, mixed=False, + in_=True, patchsys=True, now=True): + self._options = { + "out": out, + "err": err, + "mixed": mixed, + "in_": in_, + "patchsys": patchsys, + "now": now, + } + self._save() + if now: + self.startall() + + def _save(self): + in_ = self._options['in_'] + out = self._options['out'] + err = self._options['err'] + mixed = self._options['mixed'] + patchsys = self._options['patchsys'] + if in_: + try: + self.in_ = FDCapture(0, tmpfile=None, now=False, + patchsys=patchsys) + except OSError: + pass + if out: + tmpfile = None + if hasattr(out, 'write'): + tmpfile = out + try: + self.out = FDCapture(1, tmpfile=tmpfile, + now=False, patchsys=patchsys) + self._options['out'] = self.out.tmpfile + except OSError: + pass + if err: + if out and mixed: + tmpfile = self.out.tmpfile + elif hasattr(err, 'write'): + tmpfile = err + else: + tmpfile = None + try: + self.err = FDCapture(2, tmpfile=tmpfile, + now=False, patchsys=patchsys) + self._options['err'] = self.err.tmpfile + except OSError: + pass + + def startall(self): + if hasattr(self, 'in_'): + self.in_.start() + if hasattr(self, 'out'): + self.out.start() + if hasattr(self, 'err'): + self.err.start() + + def resume(self): + """ resume capturing with original temp files. """ + self.startall() + + def done(self, save=True): + """ return (outfile, errfile) and stop capturing. """ + outfile = errfile = None + if hasattr(self, 'out') and not self.out.tmpfile.closed: + outfile = self.out.done() + if hasattr(self, 'err') and not self.err.tmpfile.closed: + errfile = self.err.done() + if hasattr(self, 'in_'): + tmpfile = self.in_.done() + if save: + self._save() + return outfile, errfile + + def readouterr(self): + """ return snapshot value of stdout/stderr capturings. """ + if hasattr(self, "out"): + out = self._readsnapshot(self.out.tmpfile) + else: + out = "" + if hasattr(self, "err"): + err = self._readsnapshot(self.err.tmpfile) + else: + err = "" + return [out, err] + + def _readsnapshot(self, f): + f.seek(0) + res = f.read() + enc = getattr(f, "encoding", None) + if enc: + res = py.builtin._totext(res, enc, "replace") + f.truncate(0) + f.seek(0) + return res + + +class StdCapture(Capture): + """ This class allows to capture writes to sys.stdout|stderr "in-memory" + and will raise errors on tries to read from sys.stdin. It only + modifies sys.stdout|stderr|stdin attributes and does not + touch underlying File Descriptors (use StdCaptureFD for that). + """ + def __init__(self, out=True, err=True, in_=True, mixed=False, now=True): + self._oldout = sys.stdout + self._olderr = sys.stderr + self._oldin = sys.stdin + if out and not hasattr(out, 'file'): + out = TextIO() + self.out = out + if err: + if mixed: + err = out + elif not hasattr(err, 'write'): + err = TextIO() + self.err = err + self.in_ = in_ + if now: + self.startall() + + def startall(self): + if self.out: + sys.stdout = self.out + if self.err: + sys.stderr = self.err + if self.in_: + sys.stdin = self.in_ = DontReadFromInput() + + def done(self, save=True): + """ return (outfile, errfile) and stop capturing. """ + outfile = errfile = None + if self.out and not self.out.closed: + sys.stdout = self._oldout + outfile = self.out + outfile.seek(0) + if self.err and not self.err.closed: + sys.stderr = self._olderr + errfile = self.err + errfile.seek(0) + if self.in_: + sys.stdin = self._oldin + return outfile, errfile + + def resume(self): + """ resume capturing with original temp files. """ + self.startall() + + def readouterr(self): + """ return snapshot value of stdout/stderr capturings. """ + out = err = "" + if self.out: + out = self.out.getvalue() + self.out.truncate(0) + self.out.seek(0) + if self.err: + err = self.err.getvalue() + self.err.truncate(0) + self.err.seek(0) + return out, err + +class DontReadFromInput: + """Temporary stub class. Ideally when stdin is accessed, the + capturing should be turned off, with possibly all data captured + so far sent to the screen. This should be configurable, though, + because in automated test runs it is better to crash than + hang indefinitely. + """ + def read(self, *args): + raise IOError("reading from stdin while output is captured") + readline = read + readlines = read + __iter__ = read + + def fileno(self): + raise ValueError("redirected Stdin is pseudofile, has no fileno()") + def isatty(self): + return False + def close(self): + pass + +try: + devnullpath = os.devnull +except AttributeError: + if os.name == 'nt': + devnullpath = 'NUL' + else: + devnullpath = '/dev/null' |