[lttng-dev] [PATCH babeltrace] Return event fields by a field name
Xiaona Han
xiaonahappy13 at 163.com
Thu Jul 25 19:56:04 EDT 2013
Since a field may be present both in an event and its stream's scope, this returns
a list which contains all the fileds by the name. The examples are also changed
according to this API.
Signed-off-by: Xiaona Han <xiaonahappy13 at 163.com>
---
bindings/python/babeltrace.i.in | 61 ++++++++++++++++++++++++--
bindings/python/examples/example-api-test.py | 16 +++----
bindings/python/examples/sched_switch.py | 16 +++---
3 files changed, 71 insertions(+), 22 deletions(-)
diff --git a/bindings/python/babeltrace.i.in b/bindings/python/babeltrace.i.in
index dd2dacc..c478dfc 100644
--- a/bindings/python/babeltrace.i.in
+++ b/bindings/python/babeltrace.i.in
@@ -744,19 +744,48 @@ class ctf:
"""
return _bt_ctf_get_timestamp(self._e)
- def get_field(self, scope, field):
- """Return the definition of a specific field."""
+ def get_field_with_scope(self, scope, field):
+ """
+ Return the definition of a specific field.
+ Return None on error.
+ """
evDef = ctf.Definition.__new__(ctf.Definition)
try:
evDef._d = _bt_ctf_get_field(self._e, scope._d, field)
except AttributeError:
raise TypeError("in get_field, argument 2 must be a "
"Definition (scope) instance")
+ if evDef._d is None:
+ return None
+ evDef._s = scope
return evDef
- def get_field_list(self, scope):
+ def get_field(self, field):
+ """
+ Return the definition of fields by a name
+ Return None on error
+ """
+ eventScope = self.get_top_level_scope(ctf.scope.EVENT_FIELDS)
+ streamScope = self.get_top_level_scope(ctf.scope.STREAM_EVENT_CONTEXT)
+ fields_by_name = []
+
+ if eventScope is not None:
+ evDef = self.get_field_with_scope(eventScope, field)
+ if evDef is not None:
+ fields_by_name.append(evDef)
+
+ if streamScope is not None:
+ evDef = self.get_field_with_scope(streamScope, field)
+ if evDef is not None:
+ fields_by_name.append(evDef);
+
+ if not fields_by_name:
+ return None
+ return fields_by_name
+
+ def get_field_list_with_scope(self, scope):
"""
- Return a list of Definitions
+ Return a list of Definitions associated with the scope
Return None on error.
"""
try:
@@ -779,10 +808,31 @@ class ctf:
#_bt_python_field_listcaller
break
+ tmp._s = scope
def_list.append(tmp)
i += 1
return def_list
+ def get_field_list(self):
+ """Return a list of Definitions or None on error."""
+ eventScope = self.get_top_level_scope(ctf.scope.EVENT_FIELDS)
+ streamScope = self.get_top_level_scope(ctf.scope.STREAM_EVENT_CONTEXT)
+
+ def_list = []
+ if eventScope is not None:
+ event_field_list = self.get_field_list_with_scope(eventScope)
+ if event_field_list is not None:
+ def_list = event_field_list
+
+ if streamScope is not None:
+ event_field_list = self.get_field_list_with_scope(streamScope)
+ if event_field_list is not None:
+ def_list.extend(event_field_list)
+
+ if not def_list:
+ return None
+ return def_list
+
def get_index(self, field, index):
"""
If the field is an array or a sequence, return the element
@@ -918,6 +968,9 @@ class ctf:
"""
return _bt_ctf_get_string(self._d)
+ def get_scope(self):
+ """Return the scope of a field or None on error."""
+ return self._s
class EventDecl(object):
"""Event declaration class. Do not instantiate."""
diff --git a/bindings/python/examples/example-api-test.py b/bindings/python/examples/example-api-test.py
index fc59e24..5846fac 100644
--- a/bindings/python/examples/example-api-test.py
+++ b/bindings/python/examples/example-api-test.py
@@ -50,23 +50,19 @@ while(event is not None):
event.get_cycles(), event.get_name()))
if event.get_name() == "sched_switch":
- sco = event.get_top_level_scope(ctf.scope.EVENT_FIELDS)
- prev_field = event.get_field(sco, "_prev_comm")
- prev_comm = prev_field.get_char_array()
-
- if ctf.field_error():
+ prev_field = event.get_field("_prev_comm")
+ if prev_field is None:
print("ERROR: Missing prev_comm context info")
else:
+ prev_comm = prev_field[0].get_char_array()
print("sched_switch prev_comm: {}".format(prev_comm))
if event.get_name() == "exit_syscall":
- sco = event.get_top_level_scope(ctf.scope.EVENT_FIELDS)
- ret_field = event.get_field(sco, "_ret")
- ret_code = ret_field.get_int64()
-
- if ctf.field_error():
+ ret_field = event.get_field("_ret")
+ if ret_field is None:
print("ERROR: Unable to extract ret")
else:
+ ret_code = ret_field[0].get_int64()
print("exit_syscall ret: {}".format(ret_code))
ret = ctf_it.next()
diff --git a/bindings/python/examples/sched_switch.py b/bindings/python/examples/sched_switch.py
index d5ed25b..83c191f 100644
--- a/bindings/python/examples/sched_switch.py
+++ b/bindings/python/examples/sched_switch.py
@@ -57,7 +57,7 @@ while event is not None:
break # Next event
# Getting PID
- pid_field = event.get_field(sco, "_pid")
+ pid_field = event.get_field_with_scope(sco, "_pid")
pid = pid_field.get_int64()
if ctf.field_error():
@@ -70,43 +70,43 @@ while event is not None:
sco = event.get_top_level_scope(ctf.scope.EVENT_FIELDS)
# prev_comm
- field = event.get_field(sco, "_prev_comm")
+ field = event.get_field_with_scope(sco, "_prev_comm")
prev_comm = field.get_char_array()
if ctf.field_error():
print("ERROR: Missing prev_comm context info")
# prev_tid
- field = event.get_field(sco, "_prev_tid")
+ field = event.get_field_with_scope(sco, "_prev_tid")
prev_tid = field.get_int64()
if ctf.field_error():
print("ERROR: Missing prev_tid context info")
# prev_prio
- field = event.get_field(sco, "_prev_prio")
+ field = event.get_field_with_scope(sco, "_prev_prio")
prev_prio = field.get_int64()
if ctf.field_error():
print("ERROR: Missing prev_prio context info")
# prev_state
- field = event.get_field(sco, "_prev_state")
+ field = event.get_field_with_scope(sco, "_prev_state")
prev_state = field.get_int64()
if ctf.field_error():
print("ERROR: Missing prev_state context info")
# next_comm
- field = event.get_field(sco, "_next_comm")
+ field = event.get_field_with_scope(sco, "_next_comm")
next_comm = field.get_char_array()
if ctf.field_error():
print("ERROR: Missing next_comm context info")
# next_tid
- field = event.get_field(sco, "_next_tid")
+ field = event.get_field_with_scope(sco, "_next_tid")
next_tid = field.get_int64()
if ctf.field_error():
print("ERROR: Missing next_tid context info")
# next_prio
- field = event.get_field(sco, "_next_prio")
+ field = event.get_field_with_scope(sco, "_next_prio")
next_prio = field.get_int64()
if ctf.field_error():
print("ERROR: Missing next_prio context info")
--
1.7.1
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