1 /*
2  * Copyright (C) 2018 The Android Open Source Project
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  *  * Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  *  * Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in
12  *    the documentation and/or other materials provided with the
13  *    distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19  * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #pragma once
30 
31 #include <malloc.h>
32 #include <stdbool.h>
33 #include <stdint.h>
34 
35 // Structures for android_mallopt.
36 
37 typedef struct {
38   // Pointer to the buffer allocated by a call to M_GET_MALLOC_LEAK_INFO.
39   uint8_t* buffer;
40   // The size of the "info" buffer.
41   size_t overall_size;
42   // The size of a single entry.
43   size_t info_size;
44   // The sum of all allocations that have been tracked. Does not include
45   // any heap overhead.
46   size_t total_memory;
47   // The maximum number of backtrace entries.
48   size_t backtrace_size;
49 } android_mallopt_leak_info_t;
50 
51 // Opcodes for android_mallopt.
52 
53 enum {
54   // Marks the calling process as a profileable zygote child, possibly
55   // initializing profiling infrastructure.
56   M_INIT_ZYGOTE_CHILD_PROFILING = 1,
57 #define M_INIT_ZYGOTE_CHILD_PROFILING M_INIT_ZYGOTE_CHILD_PROFILING
58   M_RESET_HOOKS = 2,
59 #define M_RESET_HOOKS M_RESET_HOOKS
60   // Set an upper bound on the total size in bytes of all allocations made
61   // using the memory allocation APIs.
62   //   arg = size_t*
63   //   arg_size = sizeof(size_t)
64   M_SET_ALLOCATION_LIMIT_BYTES = 3,
65 #define M_SET_ALLOCATION_LIMIT_BYTES M_SET_ALLOCATION_LIMIT_BYTES
66   // Called after the zygote forks to indicate this is a child.
67   M_SET_ZYGOTE_CHILD = 4,
68 #define M_SET_ZYGOTE_CHILD M_SET_ZYGOTE_CHILD
69 
70   // Options to dump backtraces of allocations. These options only
71   // work when malloc debug has been enabled.
72 
73   // Writes the backtrace information of all current allocations to a file.
74   // NOTE: arg_size has to be sizeof(FILE*) because FILE is an opaque type.
75   //   arg = FILE*
76   //   arg_size = sizeof(FILE*)
77   M_WRITE_MALLOC_LEAK_INFO_TO_FILE = 5,
78 #define M_WRITE_MALLOC_LEAK_INFO_TO_FILE M_WRITE_MALLOC_LEAK_INFO_TO_FILE
79   // Get information about the backtraces of all
80   //   arg = android_mallopt_leak_info_t*
81   //   arg_size = sizeof(android_mallopt_leak_info_t)
82   M_GET_MALLOC_LEAK_INFO = 6,
83 #define M_GET_MALLOC_LEAK_INFO M_GET_MALLOC_LEAK_INFO
84   // Free the memory allocated and returned by M_GET_MALLOC_LEAK_INFO.
85   //   arg = android_mallopt_leak_info_t*
86   //   arg_size = sizeof(android_mallopt_leak_info_t)
87   M_FREE_MALLOC_LEAK_INFO = 7,
88 #define M_FREE_MALLOC_LEAK_INFO M_FREE_MALLOC_LEAK_INFO
89   // Query whether the current process is considered to be profileable by the
90   // Android platform. Result is assigned to the arg pointer's destination.
91   //   arg = bool*
92   //   arg_size = sizeof(bool)
93   M_GET_PROCESS_PROFILEABLE = 9,
94 #define M_GET_PROCESS_PROFILEABLE M_GET_PROCESS_PROFILEABLE
95   // Maybe enable GWP-ASan. Set *arg to force GWP-ASan to be turned on,
96   // otherwise this mallopt() will internally decide whether to sample the
97   // process. The program must be single threaded at the point when the
98   // android_mallopt function is called.
99   //   arg = bool*
100   //   arg_size = sizeof(bool)
101   M_INITIALIZE_GWP_ASAN = 10,
102 #define M_INITIALIZE_GWP_ASAN M_INITIALIZE_GWP_ASAN
103 };
104 
105 // Manipulates bionic-specific handling of memory allocation APIs such as
106 // malloc. Only for use by the Android platform itself.
107 //
108 // On success, returns true. On failure, returns false and sets errno.
109 extern "C" bool android_mallopt(int opcode, void* arg, size_t arg_size);
110