view tests/test-newercgi.t @ 26375:3686fa2b8eee

windows: insert file positioning call between reads and writes

fopen() and fdopen() have a unique-to-Windows requirement that
transitions between read and write operations in files opened
in modes r+, w+, and a+ perform a file positioning call
(fsetpos, fseek, or rewind) in between. While the MSDN docs don't
say what will happen if this is not done, observations reveal
that Python raises an IOError with errno 0. Furthermore, I
/think/ this behavior isn't deterministic. But I can reproduce
it reliably with subsequent patches applied that open revlogs
in a+ mode and perform both reads and writes.

This patch introduces a proxy class for file handles opened
in r+, w+, and a+ mode on Windows. The class intercepts calls
and audits whether a file positioning function has been called
between read and write operations. If not, a dummy, no-op seek
to the current file position is performed. This appears to be
sufficient to "trick" Windows into allowing transitions between
read and writes without raising errors.

#require no-msys # MSYS will translate web paths as if they were file paths

This is a rudimentary test of the CGI files as of d74fc8dec2b4.

  $ hg init test

  $ cat >hgweb.cgi <<HGWEB
  > #!/usr/bin/env python
  > #
  > # An example CGI script to use hgweb, edit as necessary
  > 
  > import cgitb
  > cgitb.enable()
  > 
  > from mercurial import demandimport; demandimport.enable()
  > from mercurial.hgweb import hgweb
  > from mercurial.hgweb import wsgicgi
  > 
  > application = hgweb("test", "Empty test repository")
  > wsgicgi.launch(application)
  > HGWEB

  $ chmod 755 hgweb.cgi

  $ cat >hgweb.config <<HGWEBDIRCONF
  > [paths]
  > test = test
  > HGWEBDIRCONF

  $ cat >hgwebdir.cgi <<HGWEBDIR
  > #!/usr/bin/env python
  > #
  > # An example CGI script to export multiple hgweb repos, edit as necessary
  > 
  > import cgitb
  > cgitb.enable()
  > 
  > from mercurial import demandimport; demandimport.enable()
  > from mercurial.hgweb import hgwebdir
  > from mercurial.hgweb import wsgicgi
  > 
  > application = hgwebdir("hgweb.config")
  > wsgicgi.launch(application)
  > HGWEBDIR

  $ chmod 755 hgwebdir.cgi

  $ . "$TESTDIR/cgienv"
  $ python hgweb.cgi > page1
  $ python hgwebdir.cgi > page2

  $ PATH_INFO="/test/"
  $ PATH_TRANSLATED="/var/something/test.cgi"
  $ REQUEST_URI="/test/test/"
  $ SCRIPT_URI="http://hg.omnifarious.org/test/test/"
  $ SCRIPT_URL="/test/test/"
  $ python hgwebdir.cgi > page3

  $ grep -i error page1 page2 page3
  [1]