+import SCons.Util
+
+# list of graphics file extensions for TeX and LaTeX
+TexGraphics = ['.eps', '.ps']
+LatexGraphics = ['.pdf', '.png', '.jpg', '.gif', '.tif']
+
+# Used as a return value of modify_env_var if the variable is not set.
+class _Null:
+ pass
+_null = _Null
+
+# The user specifies the paths in env[variable], similar to other builders.
+# They may be relative and must be converted to absolute, as expected
+# by LaTeX and Co. The environment may already have some paths in
+# env['ENV'][var]. These paths are honored, but the env[var] paths have
+# higher precedence. All changes are un-done on exit.
+def modify_env_var(env, var, abspath):
+ try:
+ save = env['ENV'][var]
+ except KeyError:
+ save = _null
+ env.PrependENVPath(var, abspath)
+ try:
+ if SCons.Util.is_List(env[var]):
+ #TODO(1.5)
+ #env.PrependENVPath(var, [os.path.abspath(str(p)) for p in env[var]])
+ env.PrependENVPath(var, [os.path.abspath(str(p)) for p in env[var]])
+ else:
+ # Split at os.pathsep to convert into absolute path
+ #TODO(1.5) env.PrependENVPath(var, [os.path.abspath(p) for p in str(env[var]).split(os.pathsep)])
+ env.PrependENVPath(var, [os.path.abspath(p) for p in str(env[var]).split(os.pathsep)])
+ except KeyError:
+ pass
+
+ # Convert into a string explicitly to append ":" (without which it won't search system
+ # paths as well). The problem is that env.AppendENVPath(var, ":")
+ # does not work, refuses to append ":" (os.pathsep).
+
+ if SCons.Util.is_List(env['ENV'][var]):
+ # TODO(1.5)
+ #env['ENV'][var] = os.pathsep.join(env['ENV'][var])
+ env['ENV'][var] = os.pathsep.join(env['ENV'][var])
+ # Append the trailing os.pathsep character here to catch the case with no env[var]
+ env['ENV'][var] = env['ENV'][var] + os.pathsep
+
+ return save
+
+class FindENVPathDirs:
+ """A class to bind a specific *PATH variable name to a function that
+ will return all of the *path directories."""
+ def __init__(self, variable):
+ self.variable = variable
+ def __call__(self, env, dir=None, target=None, source=None, argument=None):
+ import SCons.PathList
+ try:
+ path = env['ENV'][self.variable]
+ except KeyError:
+ return ()
+
+ dir = dir or env.fs._cwd
+ path = SCons.PathList.PathList(path).subst_path(env, target, source)
+ return tuple(dir.Rfindalldirs(path))
+
+