[ SEA-GHOST MINI SHELL]
#!/usr/bin/python -u
#
# This tests custom input callbacks
#
import sys
import libxml2
try:
import StringIO
str_io = StringIO.StringIO
except:
import io
str_io = io.StringIO
# We implement a new scheme, py://strings/ that will reference this dictionary
pystrings = {
'catalogs/catalog.xml' :
'''<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN" "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd">
<catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog">
<rewriteSystem systemIdStartString="http://example.com/dtds/" rewritePrefix="../dtds/"/>
</catalog>''',
'xml/sample.xml' :
'''<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE root SYSTEM "http://example.com/dtds/sample.dtd">
<root>&sample.entity;</root>''',
'dtds/sample.dtd' :
'''
<!ELEMENT root (#PCDATA)>
<!ENTITY sample.entity "replacement text">'''
}
prefix = "py://strings/"
startURL = prefix + "xml/sample.xml"
catURL = prefix + "catalogs/catalog.xml"
def my_input_cb(URI):
if not(URI.startswith(prefix)):
return None
path = URI[len(prefix):]
if path not in pystrings:
return None
return str_io(pystrings[path])
def run_test(desc, docpath, catalog, exp_status="verified", exp_err=[], test_callback=None,
root_name="root", root_content="replacement text"):
opts = libxml2.XML_PARSE_DTDLOAD | libxml2.XML_PARSE_NONET | libxml2.XML_PARSE_COMPACT
actual_err = []
def my_global_error_cb(ctx, msg):
actual_err.append((-1, msg))
def my_ctx_error_cb(arg, msg, severity, reserved):
actual_err.append((severity, msg))
libxml2.registerErrorHandler(my_global_error_cb, None)
try:
parser = libxml2.createURLParserCtxt(docpath, opts)
parser.setErrorHandler(my_ctx_error_cb, None)
if catalog is not None:
parser.addLocalCatalog(catalog)
if test_callback is not None:
test_callback()
parser.parseDocument()
doc = parser.doc()
actual_status = "loaded"
e = doc.getRootElement()
if e.name == root_name and e.content == root_content:
actual_status = "verified"
doc.freeDoc()
except libxml2.parserError:
actual_status = "not loaded"
if actual_status != exp_status:
print("Test '%s' failed: expect status '%s', actual '%s'" % (desc, exp_status, actual_status))
sys.exit(1)
elif actual_err != exp_err:
print("Test '%s' failed" % desc)
print("Expect errors:")
for s,m in exp_err: print(" [%2d] '%s'" % (s,m))
print("Actual errors:")
for s,m in actual_err: print(" [%2d] '%s'" % (s,m))
sys.exit(1)
# Check that we cannot read custom schema without custom callback
run_test(desc="Loading entity without custom callback",
docpath=startURL, catalog=None,
exp_status="not loaded", exp_err=[
(-1, "I/O "),
(-1, "warning : "),
(-1, "failed to load external entity \"py://strings/xml/sample.xml\"\n")
])
# Register handler and try to load the same entity
libxml2.registerInputCallback(my_input_cb)
run_test(desc="Loading entity with custom callback",
docpath=startURL, catalog=None,
exp_status="loaded", exp_err=[
(-1, "Attempt to load network entity http://example.com/dtds/sample.dtd"),
( 4, "Entity 'sample.entity' not defined\n")
])
# Register a catalog (also accessible via pystr://) and retry
run_test(desc="Loading entity with custom callback and catalog",
docpath=startURL, catalog=catURL)
# Unregister custom callback when parser is already created
run_test(desc="Loading entity and unregistering callback",
docpath=startURL, catalog=catURL,
test_callback=lambda: libxml2.popInputCallbacks(),
exp_status="loaded", exp_err=[
( 3, "failed to load external entity \"py://strings/dtds/sample.dtd\"\n"),
( 4, "Entity 'sample.entity' not defined\n")
])
# Try to load the document again
run_test(desc="Retry loading document after unregistering callback",
docpath=startURL, catalog=catURL,
exp_status="not loaded", exp_err=[
(-1, "I/O "),
(-1, "warning : "),
(-1, "failed to load external entity \"py://strings/xml/sample.xml\"\n")
])
# But should be able to read standard I/O yet...
run_test(desc="Loading using standard i/o after unregistering callback",
docpath="tst.xml", catalog=None,
root_name='doc', root_content='bar')
# Now pop ALL input callbacks, should fail to load even standard I/O
try:
while True:
libxml2.popInputCallbacks()
except IndexError:
pass
run_test(desc="Loading using standard i/o after unregistering all callbacks",
docpath="tst.xml", catalog=None,
exp_status="not loaded", exp_err=[
(-1, "I/O "),
(-1, "warning : "),
(-1, "failed to load external entity \"tst.xml\"\n")
])
print("OK")
sys.exit(0);
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