1//===-- AppleGetPendingItemsHandler.h ----------------------------*- C++
2//-*-===//
3//
4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5// See https://llvm.org/LICENSE.txt for license information.
6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7//
8//===----------------------------------------------------------------------===//
9
10#ifndef LLDB_SOURCE_PLUGINS_SYSTEMRUNTIME_MACOSX_APPLEGETPENDINGITEMSHANDLER_H
11#define LLDB_SOURCE_PLUGINS_SYSTEMRUNTIME_MACOSX_APPLEGETPENDINGITEMSHANDLER_H
12
13#include <map>
14#include <mutex>
15#include <vector>
16
17#include "lldb/Symbol/CompilerType.h"
18#include "lldb/Utility/Status.h"
19#include "lldb/lldb-public.h"
20
21// This class will insert a UtilityFunction into the inferior process for
22// calling libBacktraceRecording's
23// __introspection_dispatch_queue_get_pending_items()
24// function. The function in the inferior will return a struct by value
25// with these members:
26//
27// struct get_pending_items_return_values
28// {
29// introspection_dispatch_item_info_ref *items_buffer;
30// uint64_t items_buffer_size;
31// uint64_t count;
32// };
33//
34// The items_buffer pointer is an address in the inferior program's address
35// space (items_buffer_size in size) which must be mach_vm_deallocate'd by
36// lldb. count is the number of items that were stored in the buffer.
37//
38// The AppleGetPendingItemsHandler object should persist so that the
39// UtilityFunction
40// can be reused multiple times.
41
42namespace lldb_private {
43
44class AppleGetPendingItemsHandler {
45public:
46 AppleGetPendingItemsHandler(lldb_private::Process *process);
47
48 ~AppleGetPendingItemsHandler();
49
50 struct GetPendingItemsReturnInfo {
51 lldb::addr_t items_buffer_ptr =
52 LLDB_INVALID_ADDRESS; /* the address of the pending items buffer
53 from libBacktraceRecording */
54 lldb::addr_t items_buffer_size = 0; /* the size of the pending items buffer
55 from libBacktraceRecording */
56 uint64_t count = 0; /* the number of pending items included in the buffer */
57
58 GetPendingItemsReturnInfo() = default;
59 };
60
61 /// Get the list of pending items for a given queue via a call to
62 /// __introspection_dispatch_queue_get_pending_items. If there's a page of
63 /// memory that needs to be freed, pass in the address and size and it will
64 /// be freed before getting the list of queues.
65 ///
66 /// \param [in] thread
67 /// The thread to run this plan on.
68 ///
69 /// \param [in] queue
70 /// The dispatch_queue_t value for the queue of interest.
71 ///
72 /// \param [in] page_to_free
73 /// An address of an inferior process vm page that needs to be
74 /// deallocated,
75 /// LLDB_INVALID_ADDRESS if this is not needed.
76 ///
77 /// \param [in] page_to_free_size
78 /// The size of the vm page that needs to be deallocated if an address was
79 /// passed in to page_to_free.
80 ///
81 /// \param [out] error
82 /// This object will be updated with the error status / error string from
83 /// any failures encountered.
84 ///
85 /// \returns
86 /// The result of the inferior function call execution. If there was a
87 /// failure of any kind while getting
88 /// the information, the items_buffer_ptr value will be
89 /// LLDB_INVALID_ADDRESS.
90 GetPendingItemsReturnInfo GetPendingItems(Thread &thread, lldb::addr_t queue,
91 lldb::addr_t page_to_free,
92 uint64_t page_to_free_size,
93 lldb_private::Status &error);
94
95 void Detach();
96
97private:
98 lldb::addr_t
99 SetupGetPendingItemsFunction(Thread &thread,
100 ValueList &get_pending_items_arglist);
101
102 static const char *g_get_pending_items_function_name;
103 static const char *g_get_pending_items_function_code;
104
105 lldb_private::Process *m_process;
106 std::unique_ptr<UtilityFunction> m_get_pending_items_impl_code;
107 std::mutex m_get_pending_items_function_mutex;
108
109 lldb::addr_t m_get_pending_items_return_buffer_addr;
110 std::mutex m_get_pending_items_retbuffer_mutex;
111};
112
113} // using namespace lldb_private
114
115#endif // LLDB_SOURCE_PLUGINS_SYSTEMRUNTIME_MACOSX_APPLEGETPENDINGITEMSHANDLER_H
116

source code of lldb/source/Plugins/SystemRuntime/MacOSX/AppleGetPendingItemsHandler.h