lyx_mirror/lib/scripts/lyxpreview_tools.py
Angus Leeming 132d2a2da7 Enable instant preview to work if the path to GhostScript contains spaces (bug
2193).


git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@10710 a592a061-630c-0410-9148-cb99ea01b6c8
2006-01-05 14:13:14 +00:00

200 lines
5.4 KiB
Python

#! /usr/bin/env python
# file lyxpreview_tools.py
# This file is part of LyX, the document processor.
# Licence details can be found in the file COPYING.
# author Angus Leeming
# Full author contact details are available in file CREDITS
# and with much help testing the code under Windows from
# Paul A. Rubin, rubin@msu.edu.
# A repository of the following functions, used by the lyxpreview2xyz scripts.
# copyfileobj, error, find_exe, find_exe_or_terminate, mkstemp,
# run_command, warning
import os, re, string, sys, tempfile
use_win32_modules = 0
if os.name == "nt":
use_win32_modules = 1
try:
import pywintypes
import win32con
import win32event
import win32file
import win32pipe
import win32process
import win32security
import winerror
except:
sys.stderr.write("Consider installing the PyWin extension modules "\
"if you're irritated by windows appearing briefly.\n")
use_win32_modules = 0
def warning(message):
sys.stderr.write(message + '\n')
def error(message):
sys.stderr.write(message + '\n')
sys.exit(1)
def find_exe(candidates, path):
for prog in candidates:
for directory in path:
if os.name == "nt":
full_path = os.path.join(directory, prog + ".exe")
else:
full_path = os.path.join(directory, prog)
if os.access(full_path, os.X_OK):
# The thing is in the PATH already (or we wouldn't
# have found it). Return just the basename to avoid
# problems when the path to the executable contains
# spaces.
return os.path.basename(full_path)
return None
def find_exe_or_terminate(candidates, path):
exe = find_exe(candidates, path)
if exe == None:
error("Unable to find executable from '%s'" % string.join(candidates))
return exe
def run_command_popen(cmd):
handle = os.popen(cmd, 'r')
cmd_stdout = handle.read()
cmd_status = handle.close()
return cmd_status, cmd_stdout
def run_command_win32(cmd):
sa = win32security.SECURITY_ATTRIBUTES()
sa.bInheritHandle = True
stdout_r, stdout_w = win32pipe.CreatePipe(sa, 0)
si = win32process.STARTUPINFO()
si.dwFlags = (win32process.STARTF_USESTDHANDLES
| win32process.STARTF_USESHOWWINDOW)
si.wShowWindow = win32con.SW_HIDE
si.hStdOutput = stdout_w
process, thread, pid, tid = \
win32process.CreateProcess(None, cmd, None, None, True,
0, None, None, si)
if process == None:
return -1, ""
# Must close the write handle in this process, or ReadFile will hang.
stdout_w.Close()
# Read the pipe until we get an error (including ERROR_BROKEN_PIPE,
# which is okay because it happens when child process ends).
data = ""
error = 0
while 1:
try:
hr, buffer = win32file.ReadFile(stdout_r, 4096)
if hr != winerror.ERROR_IO_PENDING:
data = data + buffer
except pywintypes.error, e:
if e.args[0] != winerror.ERROR_BROKEN_PIPE:
error = 1
break
if error:
return -2, ""
# Everything is okay --- the called process has closed the pipe.
# For safety, check that the process ended, then pick up its exit code.
win32event.WaitForSingleObject(process, win32event.INFINITE)
if win32process.GetExitCodeProcess(process):
return -3, ""
return None, data
def run_command(cmd):
if use_win32_modules:
return run_command_win32(cmd)
else:
return run_command_popen(cmd)
def get_version_info():
version_re = re.compile("([0-9])\.([0-9])")
match = version_re.match(sys.version)
if match == None:
error("Unable to extract version info from 'sys.version'")
return string.atoi(match.group(1)), string.atoi(match.group(2))
def copyfileobj(fsrc, fdst, rewind=0, length=16*1024):
"""copy data from file-like object fsrc to file-like object fdst"""
if rewind:
fsrc.flush()
fsrc.seek(0)
while 1:
buf = fsrc.read(length)
if not buf:
break
fdst.write(buf)
class TempFile:
"""clone of tempfile.TemporaryFile to use with python < 2.0."""
# Cache the unlinker so we don't get spurious errors at shutdown
# when the module-level "os" is None'd out. Note that this must
# be referenced as self.unlink, because the name TempFile
# may also get None'd out before __del__ is called.
unlink = os.unlink
def __init__(self):
self.filename = tempfile.mktemp()
self.file = open(self.filename,"w+b")
self.close_called = 0
def close(self):
if not self.close_called:
self.close_called = 1
self.file.close()
self.unlink(self.filename)
def __del__(self):
self.close()
def read(self, size = -1):
return self.file.read(size)
def write(self, line):
return self.file.write(line)
def seek(self, offset):
return self.file.seek(offset)
def flush(self):
return self.file.flush()
def mkstemp():
"""create a secure temporary file and return its object-like file"""
major, minor = get_version_info()
if major >= 2 and minor >= 0:
return tempfile.TemporaryFile()
else:
return TempFile()