gyp: improve Windows+Cygwin compatibility

Fixes: #1782
PR-URL: #1817
Reviewed-By: Christian Clauss <cclauss@me.com>
Reviewed-By: Rod Vagg <r@va.gg>

gyp/gyp_main.py

@@ -6,10 +6,38 @@
 
 import os
 import sys
+import subprocess
+
+# Below IsCygwin() function copied from pylib/gyp/common.py
+def IsCygwin():
+ try:
+ out = subprocess.Popen("uname",
+ stdout=subprocess.PIPE,
+ stderr=subprocess.STDOUT)
+ stdout,stderr = out.communicate()
+ return "CYGWIN" in str(stdout)
+ except Exception:
+ return False
+
+
+def UnixifyPath(path):
+ try:
+ if not IsCygwin():
+ return path
+ out = subprocess.Popen(["cygpath", "-u", path],
+ stdout=subprocess.PIPE,
+ stderr=subprocess.STDOUT)
+ stdout,stderr = out.communicate()
+ return str(stdout)
+ except Exception:
+ return path
+
 
 # Make sure we're using the version of pylib in this repo, not one installed
-# elsewhere on the system.
-sys.path.insert(0, os.path.join(os.path.dirname(sys.argv[0]), 'pylib'))
+# elsewhere on the system. Also convert to Unix style path on Cygwin systems,
+# else the 'gyp' library will not be found
+path = UnixifyPath(sys.argv[0])
+sys.path.insert(0, os.path.join(os.path.dirname(path), 'pylib'))
 import gyp
 
 if __name__ == '__main__':

gyp/pylib/gyp/common.py

@@ -9,6 +9,7 @@
 import re
 import tempfile
 import sys
+import subprocess
 
 
 # A minimal memoizing decorator. It'll blow up if the args aren't immutable,
@@ -337,11 +338,16 @@ def WriteOnDiff(filename):
  class Writer(object):
  """Wrapper around file which only covers the target if it differs."""
  def __init__(self):
+ # On Cygwin remove the "dir" argument because `C:` prefixed paths are treated as relative,
+ # consequently ending up with current dir "/cygdrive/c/..." being prefixed to those, which was
+ # obviously a non-existent path, for example: "/cygdrive/c/<some folder>/C:\<my win style abs path>".
+ # See https://docs.python.org/2/library/tempfile.html#tempfile.mkstemp for more details
+ base_temp_dir = "" if IsCygwin() else os.path.dirname(filename)
  # Pick temporary file.
  tmp_fd, self.tmp_path = tempfile.mkstemp(
  suffix='.tmp',
  prefix=os.path.split(filename)[1] + '.gyp.',
- dir=os.path.split(filename)[0])
+ dir=base_temp_dir)
  try:
  self.tmp_file = os.fdopen(tmp_fd, 'wb')
  except Exception:
@@ -611,3 +617,14 @@ def CrossCompileRequested():
  os.environ.get('AR_target') or
  os.environ.get('CC_target') or
  os.environ.get('CXX_target'))
+
+def IsCygwin():
+ try:
+ out = subprocess.Popen("uname",
+ stdout=subprocess.PIPE,
+ stderr=subprocess.STDOUT)
+ stdout,stderr = out.communicate()
+ return "CYGWIN" in str(stdout)
+ except Exception:
+ return False
+

gyp/pylib/gyp/generator/msvs.py

@@ -165,7 +165,7 @@ def _FixPath(path):
  Returns:
  The path with all slashes made into backslashes.
  """
- if fixpath_prefix and path and not os.path.isabs(path) and not path[0] == '$':
+ if fixpath_prefix and path and not os.path.isabs(path) and not path[0] == '$' and not _IsWindowsAbsPath(path):
  path = os.path.join(fixpath_prefix, path)
  path = path.replace('/', '\\')
  path = _NormalizedSource(path)
@@ -174,6 +174,16 @@ def _FixPath(path):
  return path
 
 
+def _IsWindowsAbsPath(path):
+ """
+ On Cygwin systems Python needs a little help determining if a path is an absolute Windows path or not, so that
+ it does not treat those as relative, which results in bad paths like:
+
+ '..\C:\<some path>\some_source_code_file.cc'
+ """
+ return path.startswith('c:') or path.startswith('C:')
+
+
 def _FixPaths(paths):
  """Fix each of the paths of the list."""
  return [_FixPath(i) for i in paths]

lib/configure.js

@@ -295,6 +295,7 @@ function configure (gyp, argv, callback) {
  outputDir = buildDir
  }
  var nodeGypDir = path.resolve(__dirname, '..')
+
  var nodeLibFile = path.join(nodeDir,
  !gyp.opts.nodedir ? '<(target_arch)' : '$(Configuration)',
  release.name + '.lib')
@@ -308,6 +309,12 @@ function configure (gyp, argv, callback) {
  argv.push('-Dnode_exp_file=' + nodeExpFile)
  }
  argv.push('-Dnode_gyp_dir=' + nodeGypDir)
+
+ // Do this to keep Cygwin environments happy, else the unescaped '\' gets eaten up,
+ // resulting in bad paths, Ex c:parentFolderfolderanotherFolder instead of c:\parentFolder\folder\anotherFolder
+ if (win) {
+ nodeLibFile = nodeLibFile.replace(/\\/g, '\\\\')
+ }
  argv.push('-Dnode_lib_file=' + nodeLibFile)
  argv.push('-Dmodule_root_dir=' + process.cwd())
  argv.push('-Dnode_engine=' +