Yao Chen | b3be9ea | 2018-05-07 16:57:13 -0700 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (C) 2018, The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | #include "include/stats_event_list.h" |
| 18 | |
| 19 | #include <string.h> |
| 20 | #include "statsd_writer.h" |
| 21 | |
| 22 | #define MAX_EVENT_PAYLOAD (LOGGER_ENTRY_MAX_PAYLOAD - sizeof(int32_t)) |
| 23 | |
| 24 | typedef struct { |
| 25 | uint32_t tag; |
| 26 | unsigned pos; /* Read/write position into buffer */ |
| 27 | unsigned count[ANDROID_MAX_LIST_NEST_DEPTH + 1]; /* Number of elements */ |
| 28 | unsigned list[ANDROID_MAX_LIST_NEST_DEPTH + 1]; /* pos for list counter */ |
| 29 | unsigned list_nest_depth; |
| 30 | unsigned len; /* Length or raw buffer. */ |
| 31 | bool overflow; |
| 32 | bool list_stop; /* next call decrement list_nest_depth and issue a stop */ |
| 33 | enum { |
| 34 | kAndroidLoggerRead = 1, |
| 35 | kAndroidLoggerWrite = 2, |
| 36 | } read_write_flag; |
| 37 | uint8_t storage[LOGGER_ENTRY_MAX_PAYLOAD]; |
| 38 | } android_log_context_internal; |
| 39 | |
| 40 | extern struct android_log_transport_write statsdLoggerWrite; |
| 41 | |
| 42 | static int __write_to_statsd_init(struct iovec* vec, size_t nr); |
| 43 | static int (*write_to_statsd)(struct iovec* vec, size_t nr) = __write_to_statsd_init; |
| 44 | |
| 45 | // Similar to create_android_logger(), but instead of allocation a new buffer, |
| 46 | // this function resets the buffer for resuse. |
| 47 | void reset_log_context(android_log_context ctx) { |
| 48 | if (!ctx) { |
| 49 | return; |
| 50 | } |
| 51 | android_log_context_internal* context = (android_log_context_internal*)(ctx); |
| 52 | uint32_t tag = context->tag; |
| 53 | memset(context, 0, sizeof(android_log_context_internal)); |
| 54 | |
| 55 | context->tag = tag; |
| 56 | context->read_write_flag = kAndroidLoggerWrite; |
| 57 | size_t needed = sizeof(uint8_t) + sizeof(uint8_t); |
| 58 | if ((context->pos + needed) > MAX_EVENT_PAYLOAD) { |
| 59 | context->overflow = true; |
| 60 | } |
| 61 | /* Everything is a list */ |
| 62 | context->storage[context->pos + 0] = EVENT_TYPE_LIST; |
| 63 | context->list[0] = context->pos + 1; |
| 64 | context->pos += needed; |
| 65 | } |
| 66 | |
| 67 | int stats_write_list(android_log_context ctx) { |
| 68 | android_log_context_internal* context; |
| 69 | const char* msg; |
| 70 | ssize_t len; |
| 71 | |
| 72 | context = (android_log_context_internal*)(ctx); |
| 73 | if (!context || (kAndroidLoggerWrite != context->read_write_flag)) { |
| 74 | return -EBADF; |
| 75 | } |
| 76 | |
| 77 | if (context->list_nest_depth) { |
| 78 | return -EIO; |
| 79 | } |
| 80 | |
| 81 | /* NB: if there was overflow, then log is truncated. Nothing reported */ |
| 82 | context->storage[1] = context->count[0]; |
| 83 | len = context->len = context->pos; |
| 84 | msg = (const char*)context->storage; |
| 85 | /* it's not a list */ |
| 86 | if (context->count[0] <= 1) { |
| 87 | len -= sizeof(uint8_t) + sizeof(uint8_t); |
| 88 | if (len < 0) { |
| 89 | len = 0; |
| 90 | } |
| 91 | msg += sizeof(uint8_t) + sizeof(uint8_t); |
| 92 | } |
| 93 | |
| 94 | struct iovec vec[2]; |
| 95 | vec[0].iov_base = &context->tag; |
| 96 | vec[0].iov_len = sizeof(context->tag); |
| 97 | vec[1].iov_base = (void*)msg; |
| 98 | vec[1].iov_len = len; |
| 99 | return write_to_statsd(vec, 2); |
| 100 | } |
| 101 | |
| 102 | int write_to_logger(android_log_context ctx, log_id_t id) { |
| 103 | int retValue = 0; |
| 104 | |
| 105 | if (WRITE_TO_LOGD) { |
| 106 | retValue = android_log_write_list(ctx, id); |
| 107 | } |
| 108 | |
| 109 | if (WRITE_TO_STATSD) { |
| 110 | // log_event_list's cast operator is overloaded. |
| 111 | int ret = stats_write_list(ctx); |
| 112 | // In debugging phase, we may write to both logd and statsd. Prefer to |
| 113 | // return statsd socket write error code here. |
| 114 | if (ret < 0) { |
| 115 | retValue = ret; |
| 116 | } |
| 117 | } |
| 118 | |
| 119 | return retValue; |
| 120 | } |
| 121 | |
| 122 | /* log_init_lock assumed */ |
| 123 | static int __write_to_statsd_initialize_locked() { |
| 124 | if (!statsdLoggerWrite.open || ((*statsdLoggerWrite.open)() < 0)) { |
| 125 | if (statsdLoggerWrite.close) { |
| 126 | (*statsdLoggerWrite.close)(); |
| 127 | return -ENODEV; |
| 128 | } |
| 129 | } |
| 130 | return 1; |
| 131 | } |
| 132 | |
| 133 | static int __write_to_stats_daemon(struct iovec* vec, size_t nr) { |
| 134 | int ret, save_errno; |
| 135 | struct timespec ts; |
| 136 | size_t len, i; |
| 137 | |
| 138 | for (len = i = 0; i < nr; ++i) { |
| 139 | len += vec[i].iov_len; |
| 140 | } |
| 141 | if (!len) { |
| 142 | return -EINVAL; |
| 143 | } |
| 144 | |
| 145 | save_errno = errno; |
| 146 | clock_gettime(CLOCK_REALTIME, &ts); |
| 147 | |
| 148 | ret = 0; |
| 149 | |
| 150 | ssize_t retval; |
| 151 | retval = (*statsdLoggerWrite.write)(&ts, vec, nr); |
| 152 | if (ret >= 0) { |
| 153 | ret = retval; |
| 154 | } |
| 155 | |
| 156 | errno = save_errno; |
| 157 | return ret; |
| 158 | } |
| 159 | |
| 160 | static int __write_to_statsd_init(struct iovec* vec, size_t nr) { |
| 161 | int ret, save_errno = errno; |
| 162 | |
| 163 | statsd_writer_init_lock(); |
| 164 | |
| 165 | if (write_to_statsd == __write_to_statsd_init) { |
| 166 | ret = __write_to_statsd_initialize_locked(); |
| 167 | if (ret < 0) { |
| 168 | statsd_writer_init_unlock(); |
| 169 | errno = save_errno; |
| 170 | return ret; |
| 171 | } |
| 172 | |
| 173 | write_to_statsd = __write_to_stats_daemon; |
| 174 | } |
| 175 | |
| 176 | statsd_writer_init_unlock(); |
| 177 | |
| 178 | ret = write_to_statsd(vec, nr); |
| 179 | errno = save_errno; |
| 180 | return ret; |
| 181 | } |