From: david-sarah <david-sarah@jacaranda.org>
Date: Sun, 25 Jul 2010 09:28:49 +0000 (-0700)
Subject: Add missing windows/fixups.py (for setting up Unicode args and output on Windows).
X-Git-Tag: allmydata-tahoe-1.8.0b2~58
X-Git-Url: https://git.rkrishnan.org/architecture.txt?a=commitdiff_plain;h=9d04b2a317c2ecf4a8138cca93b66d043ad79a6a;p=tahoe-lafs%2Ftahoe-lafs.git

Add missing windows/fixups.py (for setting up Unicode args and output on Windows).
---

diff --git a/src/allmydata/windows/fixups.py b/src/allmydata/windows/fixups.py
new file mode 100644
index 00000000..6a60a664
--- /dev/null
+++ b/src/allmydata/windows/fixups.py
@@ -0,0 +1,131 @@
+
+done = False
+
+def initialize():
+    global done
+    import sys
+    if sys.platform != "win32" or done:
+        return True
+    done = True
+
+    import codecs, re
+    from ctypes import WINFUNCTYPE, windll, CFUNCTYPE, cdll, POINTER, byref, \
+        c_wchar_p, c_char_p, c_void_p, c_int, c_size_t
+    from allmydata.util import log
+    from allmydata.util.encodingutil import canonical_encoding
+
+    # Work around <http://bugs.python.org/issue6058>.
+    codecs.register(lambda name: name == 'cp65001' and codecs.lookup('utf-8') or None)
+
+    # Make Unicode console output work independently of the current code page.
+    # This also fixes <http://bugs.python.org/issue1602>.
+    # Credit to Michael Kaplan <http://blogs.msdn.com/b/michkap/archive/2008/03/18/8306597.aspx>
+    # and TZOmegaTZIOY
+    # <http://stackoverflow.com/questions/878972/windows-cmd-encoding-change-causes-python-crash/1432462#1432462>.
+    try:
+        STDOUT_FILENO = 1
+        STDERR_FILENO = 2
+        real_stdout = hasattr(sys.stdout, 'fileno') and sys.stdout.fileno() == STDOUT_FILENO
+        real_stderr = hasattr(sys.stderr, 'fileno') and sys.stderr.fileno() == STDERR_FILENO
+
+        def force_utf8(stream, name):
+            if hasattr(stream, 'encoding') and canonical_encoding(stream.encoding) != 'utf-8':
+                log.msg("%s (%r) had encoding %r, but we're going to write UTF-8 to it" %
+                        (name, stream, stream.encoding), level=log.CURIOUS)
+            stream.encoding = 'utf-8'
+
+        if not real_stdout:
+            force_utf8(sys.stdout, "sys.stdout")
+
+        if not real_stderr:
+            force_utf8(sys.stderr, "sys.stderr")
+
+        if real_stdout or real_stderr:
+            # FILE * _fdopen(int fd, const char *mode);
+            # #define _IOLBF 0x0040
+            # int setvbuf(FILE *stream, char *buffer, int mode, size_t size);
+            # #define _O_U8TEXT 0x40000
+            # int _setmode(int fd, int mode);
+            # int fputws(const wchar_t *ws, FILE *stream);
+            # int fflush(FILE *stream);
+
+            c_runtime = cdll.msvcrt
+            NULL = None
+            _fdopen = CFUNCTYPE(c_void_p, c_int, c_char_p)(("_fdopen", c_runtime))
+            _IOLBF = 0x0040
+            setvbuf = CFUNCTYPE(c_int, c_void_p, c_char_p, c_int, c_size_t)(("setvbuf", c_runtime))
+            _O_U8TEXT = 0x40000
+            _setmode = CFUNCTYPE(c_int, c_int, c_int)(("_setmode", c_runtime))
+            fputws = CFUNCTYPE(c_int, c_wchar_p, c_void_p)(("fputws", c_runtime));
+            fflush = CFUNCTYPE(c_int, c_void_p)(("fflush", c_runtime));
+
+            buffer_chars = 1024
+
+            class UnicodeOutput:
+                def __init__(self, fileno, name):
+                    self._stream = _fdopen(fileno, "w")
+                    assert self._stream is not NULL
+
+                    # Deep magic. MSVCRT supports writing wide-oriented output to stdout/stderr
+                    # to the console using the Unicode APIs, but it does the conversion in the
+                    # stdio buffer, so you need that buffer to be as large as the maximum amount
+                    # you're going to write in a single call (in bytes, not characters).
+                    setvbuf(self._stream, NULL, _IOLBF, buffer_chars*4 + 100)
+                    _setmode(fileno, _O_U8TEXT)
+
+                    self._fileno = fileno
+                    self.closed = False
+                    self.softspace = False
+                    self.mode = 'w'
+                    self.encoding = 'utf-8'
+                    self.name = name
+
+                def isatty(self):
+                    return False
+                def close(self):
+                    self.closed = True
+                    self.flush()
+                def fileno(self):
+                    return self._fileno
+                def flush(self):
+                    fflush(self._stream)
+
+                def write(self, text):
+                    if not isinstance(text, unicode):
+                        text = str(text).decode('utf-8')
+                    for i in xrange(0, len(text), buffer_chars):
+                        fputws(text[i:(i+buffer_chars)], self._stream)
+                        fflush(self._stream)
+
+                def writelines(self, lines):
+                    for line in lines:
+                        self.write(line)
+
+            if real_stdout:
+                sys.stdout = UnicodeOutput(STDOUT_FILENO, '<Unicode stdout>')
+
+            if real_stderr:
+                sys.stderr = UnicodeOutput(STDERR_FILENO, '<Unicode stderr>')
+    except Exception, e:
+        log.msg("exception %r while fixing up sys.stdout and sys.stderr" % (e,), level=log.WEIRD)
+
+    # Unmangle command-line arguments.
+    GetCommandLineW = WINFUNCTYPE(c_wchar_p)(("GetCommandLineW", windll.kernel32))
+    CommandLineToArgvW = WINFUNCTYPE(POINTER(c_wchar_p), c_wchar_p, POINTER(c_int)) \
+                            (("CommandLineToArgvW", windll.shell32))
+
+    argc = c_int(0)
+    argv_unicode = CommandLineToArgvW(GetCommandLineW(), byref(argc))
+
+    def unmangle(s):
+        return re.sub(ur'\x7f[0-9a-fA-F]*\;', lambda m: unichr(int(m.group(0)[1:-1], 16)), s)
+
+    try:
+        sys.argv = [unmangle(argv_unicode[i]).encode('utf-8') for i in xrange(1, argc.value)]
+    except Exception, e:
+        print >>sys.stderr, "%s:  could not unmangle Unicode arguments" % (sys.argv[0],)
+        print >>sys.stderr, [argv_unicode[i] for i in xrange(1, argc.value)]
+        raise
+
+    if sys.argv[0].endswith('.pyscript'):
+        sys.argv[0] = sys.argv[0][:-9]