#! /opt/alt/python37/bin/python3.7
# linktree
#
# Make a copy of a directory tree with symbolic links to all files in the
# original tree.
# All symbolic links go to a special symbolic link at the top, so you
# can easily fix things if the original source tree moves.
# See also "mkreal".
#
# usage: mklinks oldtree newtree
import sys, os
LINK = '.LINK' # Name of special symlink at the top.
debug = 0
def main():
if not 3 <= len(sys.argv) <= 4:
print('usage:', sys.argv[0], 'oldtree newtree [linkto]')
return 2
oldtree, newtree = sys.argv[1], sys.argv[2]
if len(sys.argv) > 3:
link = sys.argv[3]
link_may_fail = 1
else:
link = LINK
link_may_fail = 0
if not os.path.isdir(oldtree):
print(oldtree + ': not a directory')
return 1
try:
os.mkdir(newtree, 0o777)
except OSError as msg:
print(newtree + ': cannot mkdir:', msg)
return 1
linkname = os.path.join(newtree, link)
try:
os.symlink(os.path.join(os.pardir, oldtree), linkname)
except OSError as msg:
if not link_may_fail:
print(linkname + ': cannot symlink:', msg)
return 1
else:
print(linkname + ': warning: cannot symlink:', msg)
linknames(oldtree, newtree, link)
return 0
def linknames(old, new, link):
if debug: print('linknames', (old, new, link))
try:
names = os.listdir(old)
except OSError as msg:
print(old + ': warning: cannot listdir:', msg)
return
for name in names:
if name not in (os.curdir, os.pardir):
oldname = os.path.join(old, name)
linkname = os.path.join(link, name)
newname = os.path.join(new, name)
if debug > 1: print(oldname, newname, linkname)
if os.path.isdir(oldname) and \
not os.path.islink(oldname):
try:
os.mkdir(newname, 0o777)
ok = 1
except:
print(newname + \
': warning: cannot mkdir:', msg)
ok = 0
if ok:
linkname = os.path.join(os.pardir,
linkname)
linknames(oldname, newname, linkname)
else:
os.symlink(linkname, newname)
if __name__ == '__main__':
sys.exit(main())
