1 /* 2 * Copyright (C) 2007 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 <dirent.h> 18 #include <errno.h> 19 #include <fcntl.h> 20 #include <linux/input.h> 21 #include <stdio.h> 22 #include <stdlib.h> 23 #include <string.h> 24 #include <sys/epoll.h> 25 #include <sys/ioctl.h> 26 #include <sys/types.h> 27 #include <unistd.h> 28 29 #include <functional> 30 #include <memory> 31 32 #include <android-base/unique_fd.h> 33 34 #include "minui/minui.h" 35 36 constexpr size_t MAX_DEVICES = 16; 37 constexpr size_t MAX_MISC_FDS = 16; 38 39 constexpr size_t BITS_PER_LONG = sizeof(unsigned long) * 8; 40 constexpr size_t BITS_TO_LONGS(size_t bits) { 41 return ((bits + BITS_PER_LONG - 1) / BITS_PER_LONG); 42 } 43 44 struct FdInfo { 45 android::base::unique_fd fd; 46 ev_callback cb; 47 }; 48 49 static android::base::unique_fd g_epoll_fd; 50 static epoll_event g_polled_events[MAX_DEVICES + MAX_MISC_FDS]; 51 static int g_polled_events_count; 52 53 static FdInfo ev_fdinfo[MAX_DEVICES + MAX_MISC_FDS]; 54 55 static size_t g_ev_count = 0; 56 static size_t g_ev_dev_count = 0; 57 static size_t g_ev_misc_count = 0; 58 59 static bool test_bit(size_t bit, unsigned long* array) { // NOLINT 60 return (array[bit / BITS_PER_LONG] & (1UL << (bit % BITS_PER_LONG))) != 0; 61 } 62 63 int ev_init(ev_callback input_cb, bool allow_touch_inputs) { 64 g_epoll_fd.reset(); 65 66 android::base::unique_fd epoll_fd(epoll_create1(EPOLL_CLOEXEC)); 67 if (epoll_fd == -1) { 68 return -1; 69 } 70 71 std::unique_ptr<DIR, decltype(&closedir)> dir(opendir("/dev/input"), closedir); 72 if (!dir) { 73 return -1; 74 } 75 76 bool epoll_ctl_failed = false; 77 dirent* de; 78 while ((de = readdir(dir.get())) != nullptr) { 79 if (strncmp(de->d_name, "event", 5)) continue; 80 android::base::unique_fd fd(openat(dirfd(dir.get()), de->d_name, O_RDONLY | O_CLOEXEC)); 81 if (fd == -1) continue; 82 83 // Use unsigned long to match ioctl's parameter type. 84 unsigned long ev_bits[BITS_TO_LONGS(EV_MAX)]; // NOLINT 85 86 // Read the evbits of the input device. 87 if (ioctl(fd, EVIOCGBIT(0, sizeof(ev_bits)), ev_bits) == -1) { 88 continue; 89 } 90 91 // We assume that only EV_KEY, EV_REL, and EV_SW event types are ever needed. EV_ABS is also 92 // allowed if allow_touch_inputs is set. 93 if (!test_bit(EV_KEY, ev_bits) && !test_bit(EV_REL, ev_bits) && !test_bit(EV_SW, ev_bits)) { 94 if (!allow_touch_inputs || !test_bit(EV_ABS, ev_bits)) { 95 continue; 96 } 97 } 98 99 epoll_event ev; 100 ev.events = EPOLLIN | EPOLLWAKEUP; 101 ev.data.ptr = &ev_fdinfo[g_ev_count]; 102 if (epoll_ctl(epoll_fd, EPOLL_CTL_ADD, fd, &ev) == -1) { 103 epoll_ctl_failed = true; 104 continue; 105 } 106 107 ev_fdinfo[g_ev_count].fd.reset(fd.release()); 108 ev_fdinfo[g_ev_count].cb = input_cb; 109 g_ev_count++; 110 g_ev_dev_count++; 111 if (g_ev_dev_count == MAX_DEVICES) break; 112 } 113 114 if (epoll_ctl_failed && !g_ev_count) { 115 return -1; 116 } 117 118 g_epoll_fd.reset(epoll_fd.release()); 119 return 0; 120 } 121 122 int ev_get_epollfd(void) { 123 return g_epoll_fd.get(); 124 } 125 126 int ev_add_fd(android::base::unique_fd&& fd, ev_callback cb) { 127 if (g_ev_misc_count == MAX_MISC_FDS || cb == nullptr) { 128 return -1; 129 } 130 131 epoll_event ev; 132 ev.events = EPOLLIN | EPOLLWAKEUP; 133 ev.data.ptr = static_cast<void*>(&ev_fdinfo[g_ev_count]); 134 int ret = epoll_ctl(g_epoll_fd, EPOLL_CTL_ADD, fd, &ev); 135 if (!ret) { 136 ev_fdinfo[g_ev_count].fd.reset(fd.release()); 137 ev_fdinfo[g_ev_count].cb = std::move(cb); 138 g_ev_count++; 139 g_ev_misc_count++; 140 } 141 142 return ret; 143 } 144 145 void ev_exit(void) { 146 while (g_ev_count > 0) { 147 ev_fdinfo[--g_ev_count].fd.reset(); 148 } 149 g_ev_misc_count = 0; 150 g_ev_dev_count = 0; 151 g_epoll_fd.reset(); 152 } 153 154 int ev_wait(int timeout) { 155 g_polled_events_count = epoll_wait(g_epoll_fd, g_polled_events, g_ev_count, timeout); 156 if (g_polled_events_count <= 0) { 157 return -1; 158 } 159 return 0; 160 } 161 162 void ev_dispatch(void) { 163 for (int n = 0; n < g_polled_events_count; n++) { 164 FdInfo* fdi = static_cast<FdInfo*>(g_polled_events[n].data.ptr); 165 const ev_callback& cb = fdi->cb; 166 if (cb) { 167 cb(fdi->fd, g_polled_events[n].events); 168 } 169 } 170 } 171 172 int ev_get_input(int fd, uint32_t epevents, input_event* ev) { 173 if (epevents & EPOLLIN) { 174 ssize_t r = TEMP_FAILURE_RETRY(read(fd, ev, sizeof(*ev))); 175 if (r == sizeof(*ev)) { 176 return 0; 177 } 178 } 179 return -1; 180 } 181 182 int ev_sync_key_state(const ev_set_key_callback& set_key_cb) { 183 // Use unsigned long to match ioctl's parameter type. 184 unsigned long ev_bits[BITS_TO_LONGS(EV_MAX)]; // NOLINT 185 unsigned long key_bits[BITS_TO_LONGS(KEY_MAX)]; // NOLINT 186 187 for (size_t i = 0; i < g_ev_dev_count; ++i) { 188 memset(ev_bits, 0, sizeof(ev_bits)); 189 memset(key_bits, 0, sizeof(key_bits)); 190 191 if (ioctl(ev_fdinfo[i].fd, EVIOCGBIT(0, sizeof(ev_bits)), ev_bits) == -1) { 192 continue; 193 } 194 if (!test_bit(EV_KEY, ev_bits)) { 195 continue; 196 } 197 if (ioctl(ev_fdinfo[i].fd, EVIOCGKEY(sizeof(key_bits)), key_bits) == -1) { 198 continue; 199 } 200 201 for (int code = 0; code <= KEY_MAX; code++) { 202 if (test_bit(code, key_bits)) { 203 set_key_cb(code, 1); 204 } 205 } 206 } 207 208 return 0; 209 } 210 211 void ev_iterate_available_keys(const std::function<void(int)>& f) { 212 // Use unsigned long to match ioctl's parameter type. 213 unsigned long ev_bits[BITS_TO_LONGS(EV_MAX)]; // NOLINT 214 unsigned long key_bits[BITS_TO_LONGS(KEY_MAX)]; // NOLINT 215 216 for (size_t i = 0; i < g_ev_dev_count; ++i) { 217 memset(ev_bits, 0, sizeof(ev_bits)); 218 memset(key_bits, 0, sizeof(key_bits)); 219 220 // Does this device even have keys? 221 if (ioctl(ev_fdinfo[i].fd, EVIOCGBIT(0, sizeof(ev_bits)), ev_bits) == -1) { 222 continue; 223 } 224 if (!test_bit(EV_KEY, ev_bits)) { 225 continue; 226 } 227 228 if (ioctl(ev_fdinfo[i].fd, EVIOCGBIT(EV_KEY, KEY_MAX), key_bits) == -1) { 229 continue; 230 } 231 232 for (int key_code = 0; key_code <= KEY_MAX; ++key_code) { 233 if (test_bit(key_code, key_bits)) { 234 f(key_code); 235 } 236 } 237 } 238 } 239 240 void ev_iterate_touch_inputs(const std::function<void(int)>& action) { 241 for (size_t i = 0; i < g_ev_dev_count; ++i) { 242 // Use unsigned long to match ioctl's parameter type. 243 unsigned long ev_bits[BITS_TO_LONGS(EV_MAX)] = {}; // NOLINT 244 if (ioctl(ev_fdinfo[i].fd, EVIOCGBIT(0, sizeof(ev_bits)), ev_bits) == -1) { 245 continue; 246 } 247 if (!test_bit(EV_ABS, ev_bits)) { 248 continue; 249 } 250 251 unsigned long key_bits[BITS_TO_LONGS(KEY_MAX)] = {}; // NOLINT 252 if (ioctl(ev_fdinfo[i].fd, EVIOCGBIT(EV_ABS, KEY_MAX), key_bits) == -1) { 253 continue; 254 } 255 256 for (int key_code = 0; key_code <= KEY_MAX; ++key_code) { 257 if (test_bit(key_code, key_bits)) { 258 action(key_code); 259 } 260 } 261 } 262 } 263