add hg and python

1 files changed, 74 insertions, 0 deletions

diff --git a/sys/src/cmd/python/Demo/comparisons/systemtest.py b/sys/src/cmd/python/Demo/comparisons/systemtest.py
new file mode 100755
index 000000000..bbc313ba1
--- /dev/null
+++ b/sys/src/cmd/python/Demo/comparisons/systemtest.py
@@ -0,0 +1,74 @@
+#! /usr/bin/env python
+
+# 3)  System Test
+#
+#     Given a list of directories, report any bogus symbolic links contained
+#     anywhere in those subtrees.  A bogus symbolic link is one that cannot
+#     be resolved because it points to a nonexistent or otherwise
+#     unresolvable file.  Do *not* use an external find executable.
+#     Directories may be very very deep.  Print a warning immediately if the
+#     system you're running on doesn't support symbolic links.
+
+# This implementation:
+# - takes one optional argument, using the current directory as default
+# - uses chdir to increase performance
+# - sorts the names per directory
+# - prints output lines of the form "path1 -> path2" as it goes
+# - prints error messages about directories it can't list or chdir into
+
+import os
+import sys
+from stat import *
+
+def main():
+    try:
+        # Note: can't test for presence of lstat -- it's always there
+        dummy = os.readlink
+    except AttributeError:
+        print "This system doesn't have symbolic links"
+        sys.exit(0)
+    if sys.argv[1:]:
+        prefix = sys.argv[1]
+    else:
+        prefix = ''
+    if prefix:
+        os.chdir(prefix)
+        if prefix[-1:] != '/': prefix = prefix + '/'
+        reportboguslinks(prefix)
+    else:
+        reportboguslinks('')
+
+def reportboguslinks(prefix):
+    try:
+        names = os.listdir('.')
+    except os.error, msg:
+        print "%s%s: can't list: %s" % (prefix, '.', msg)
+        return
+    names.sort()
+    for name in names:
+        if name == os.curdir or name == os.pardir:
+            continue
+        try:
+            mode = os.lstat(name)[ST_MODE]
+        except os.error:
+            print "%s%s: can't stat: %s" % (prefix, name, msg)
+            continue
+        if S_ISLNK(mode):
+            try:
+                os.stat(name)
+            except os.error:
+                print "%s%s -> %s" % \
+                      (prefix, name, os.readlink(name))
+        elif S_ISDIR(mode):
+            try:
+                os.chdir(name)
+            except os.error, msg:
+                print "%s%s: can't chdir: %s" % \
+                      (prefix, name, msg)
+                continue
+            try:
+                reportboguslinks(prefix + name + '/')
+            finally:
+                os.chdir('..')
+
+main()