introduced Queue/Stack itervalues

This commit introduces the possibility to iterate over all elements of a Queue/Stack.
To avoid infinite loop, a maximum of MAX_ENTRIES pop() are performed

Signed-off-by: Simone Magnani <[email protected]>

src/python/bcc/table.py

@@ -1157,6 +1157,8 @@ def __init__(self, bpf, map_id, map_fd, leaftype):
  self.Leaf = leaftype
  self.ttype = lib.bpf_table_type_id(self.bpf.module, self.map_id)
  self.flags = lib.bpf_table_flags_id(self.bpf.module, self.map_id)
+ self.max_entries = int(lib.bpf_table_max_entries_id(self.bpf.module,
+ self.map_id))
 
  def leaf_sprintf(self, leaf):
  buf = ct.create_string_buffer(ct.sizeof(self.Leaf) * 8)
@@ -1193,3 +1195,16 @@ def peek(self):
  if res < 0:
  raise KeyError("Could not peek table")
  return leaf
+
+ def itervalues(self):
+ # to avoid infinite loop, set maximum pops to max_entries
+ cnt = self.max_entries
+ while cnt:
+ try:
+ yield(self.pop())
+ cnt -= 1
+ except KeyError:
+ return
+
+ def values(self):
+ return [value for value in self.itervalues()]

tests/python/test_queuestack.py

@@ -2,13 +2,12 @@
 # Copyright (c) PLUMgrid, Inc.
 # Licensed under the Apache License, Version 2.0 (the "License")
 
-from bcc import BPF
 import os
 import distutils.version
 import ctypes as ct
-import random
-import time
-import subprocess
+
+from bcc import BPF
+
 from unittest import main, TestCase, skipUnless
 
 def kernel_version_ge(major, minor):
@@ -22,8 +21,9 @@ def kernel_version_ge(major, minor):
  return False
  return True
 
+@skipUnless(kernel_version_ge(4,20), "requires kernel >= 4.20")
 class TestQueueStack(TestCase):
- @skipUnless(kernel_version_ge(4,20), "requires kernel >= 4.20")
+
  def test_stack(self):
  text = """
  BPF_STACK(stack, u64, 10);
@@ -48,9 +48,15 @@ def test_stack(self):
  with self.assertRaises(KeyError):
  stack.pop()
 
+ for i in reversed(range(10)):
+ stack.push(ct.c_uint64(i))
+
+ # testing itervalues()
+ for i,v in enumerate(stack.values()):
+ assert v.value == i
+
  b.cleanup()
 
- @skipUnless(kernel_version_ge(4,20), "requires kernel >= 4.20")
  def test_queue(self):
  text = """
  BPF_QUEUE(queue, u64, 10);
@@ -75,7 +81,15 @@ def test_queue(self):
  with self.assertRaises(KeyError):
  queue.pop()
 
+ for i in range(10):
+ queue.push(ct.c_uint64(i))
+
+ # testing itervalues()
+ for i,v in enumerate(queue.values()):
+ assert v.value == i
+
  b.cleanup()
 
+
 if __name__ == "__main__":
  main()