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      1 /*
      2  * Copyright (C) 2008 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 <fcntl.h>
     18 #include <errno.h>
     19 #include <math.h>
     20 #include <poll.h>
     21 #include <unistd.h>
     22 #include <dirent.h>
     23 #include <sys/select.h>
     24 
     25 #include <cutils/log.h>
     26 
     27 #include <linux/input.h>
     28 
     29 #include "SensorBase.h"
     30 
     31 /*****************************************************************************/
     32 
     33 SensorBase::SensorBase(
     34         const char* dev_name,
     35         const char* data_name)
     36     : dev_name(dev_name), data_name(data_name),
     37       dev_fd(-1), data_fd(-1)
     38 {
     39     if (data_name) {
     40         data_fd = openInput(data_name);
     41     }
     42 }
     43 
     44 SensorBase::~SensorBase() {
     45     if (data_fd >= 0) {
     46         close(data_fd);
     47     }
     48     if (dev_fd >= 0) {
     49         close(dev_fd);
     50     }
     51 }
     52 
     53 int SensorBase::open_device() {
     54     if (dev_fd<0 && dev_name) {
     55         dev_fd = open(dev_name, O_RDONLY);
     56         ALOGE_IF(dev_fd<0, "Couldn't open %s (%s)", dev_name, strerror(errno));
     57     }
     58     return 0;
     59 }
     60 
     61 int SensorBase::close_device() {
     62     if (dev_fd >= 0) {
     63         close(dev_fd);
     64         dev_fd = -1;
     65     }
     66     return 0;
     67 }
     68 
     69 int SensorBase::getFd() const {
     70     if (!data_name) {
     71         return dev_fd;
     72     }
     73     return data_fd;
     74 }
     75 
     76 int SensorBase::setDelay(int32_t handle, int64_t ns) {
     77     return 0;
     78 }
     79 
     80 bool SensorBase::hasPendingEvents() const {
     81     return false;
     82 }
     83 
     84 int64_t SensorBase::getTimestamp() {
     85     struct timespec t;
     86     t.tv_sec = t.tv_nsec = 0;
     87     clock_gettime(CLOCK_MONOTONIC, &t);
     88     return int64_t(t.tv_sec)*1000000000LL + t.tv_nsec;
     89 }
     90 
     91 int SensorBase::openInput(const char* inputName) {
     92     int fd = -1;
     93     const char *dirname = "/dev/input";
     94     char devname[PATH_MAX];
     95     char *filename;
     96     DIR *dir;
     97     struct dirent *de;
     98     dir = opendir(dirname);
     99     if(dir == NULL)
    100         return -1;
    101     strcpy(devname, dirname);
    102     filename = devname + strlen(devname);
    103     *filename++ = '/';
    104     while((de = readdir(dir))) {
    105         if(de->d_name[0] == '.' &&
    106                 (de->d_name[1] == '\0' ||
    107                         (de->d_name[1] == '.' && de->d_name[2] == '\0')))
    108             continue;
    109         strcpy(filename, de->d_name);
    110         fd = open(devname, O_RDONLY);
    111         if (fd>=0) {
    112             char name[80];
    113             if (ioctl(fd, EVIOCGNAME(sizeof(name) - 1), &name) < 1) {
    114                 name[0] = '\0';
    115             }
    116             if (!strcmp(name, inputName)) {
    117                 strcpy(input_name, filename);
    118                 break;
    119             } else {
    120                 close(fd);
    121                 fd = -1;
    122             }
    123         }
    124     }
    125     closedir(dir);
    126     ALOGE_IF(fd<0, "couldn't find '%s' input device", inputName);
    127     return fd;
    128 }
    129