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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 <string.h>
     22 #include <unistd.h>
     23 #include <dirent.h>
     24 #include <sys/select.h>
     25 
     26 #include <cutils/log.h>
     27 
     28 #include <linux/input.h>
     29 
     30 #include "SensorBase.h"
     31 
     32 /*****************************************************************************/
     33 
     34 SensorBase::SensorBase(
     35         const char* dev_name,
     36         const char* data_name)
     37     : dev_name(dev_name), data_name(data_name),
     38       dev_fd(-1), data_fd(-1)
     39 {
     40     if (data_name) {
     41         data_fd = openInput(data_name);
     42     }
     43 }
     44 
     45 SensorBase::~SensorBase() {
     46     if (data_fd >= 0) {
     47         close(data_fd);
     48     }
     49     if (dev_fd >= 0) {
     50         close(dev_fd);
     51     }
     52 }
     53 
     54 int SensorBase::open_device() {
     55     if (dev_fd<0 && dev_name) {
     56         dev_fd = open(dev_name, O_RDONLY);
     57         ALOGE_IF(dev_fd<0, "Couldn't open %s (%s)", dev_name, strerror(errno));
     58     }
     59     return 0;
     60 }
     61 
     62 int SensorBase::close_device() {
     63     if (dev_fd >= 0) {
     64         close(dev_fd);
     65         dev_fd = -1;
     66     }
     67     return 0;
     68 }
     69 
     70 int SensorBase::write_sys_attribute(
     71 	const char *path, const char *value, int bytes)
     72 {
     73     int fd, amt;
     74 
     75 	fd = open(path, O_WRONLY);
     76     if (fd < 0) {
     77         ALOGE("SensorBase: write_attr failed to open %s (%s)",
     78 			path, strerror(errno));
     79         return -1;
     80 	}
     81 
     82     amt = write(fd, value, bytes);
     83 	amt = ((amt == -1) ? -errno : 0);
     84 	ALOGE_IF(amt < 0, "SensorBase: write_int failed to write %s (%s)",
     85 		path, strerror(errno));
     86     close(fd);
     87 	return amt;
     88 }
     89 
     90 int SensorBase::getFd() const {
     91     if (!data_name) {
     92         return dev_fd;
     93     }
     94     return data_fd;
     95 }
     96 
     97 int SensorBase::setDelay(int32_t handle, int64_t ns) {
     98     return 0;
     99 }
    100 
    101 int64_t SensorBase::getDelay(int32_t handle) {
    102     return 0;
    103 }
    104 
    105 bool SensorBase::hasPendingEvents() const {
    106     return false;
    107 }
    108 
    109 int64_t SensorBase::getTimestamp() {
    110     struct timespec t;
    111     t.tv_sec = t.tv_nsec = 0;
    112     clock_gettime(CLOCK_MONOTONIC, &t);
    113     return int64_t(t.tv_sec)*1000000000LL + t.tv_nsec;
    114 }
    115 
    116 int SensorBase::openInput(const char* inputName) {
    117     int fd = -1;
    118     const char *dirname = "/dev/input";
    119     char devname[PATH_MAX];
    120     char *filename;
    121     DIR *dir;
    122     struct dirent *de;
    123     dir = opendir(dirname);
    124     if(dir == NULL)
    125         return -1;
    126     strcpy(devname, dirname);
    127     filename = devname + strlen(devname);
    128     *filename++ = '/';
    129     while((de = readdir(dir))) {
    130         if(de->d_name[0] == '.' &&
    131                 (de->d_name[1] == '\0' ||
    132                         (de->d_name[1] == '.' && de->d_name[2] == '\0')))
    133             continue;
    134         strcpy(filename, de->d_name);
    135         fd = open(devname, O_RDONLY);
    136         if (fd>=0) {
    137             char name[80];
    138             if (ioctl(fd, EVIOCGNAME(sizeof(name) - 1), &name) < 1) {
    139                 name[0] = '\0';
    140             }
    141             if (!strcmp(name, inputName)) {
    142                 strcpy(input_name, filename);
    143                 break;
    144             } else {
    145                 close(fd);
    146                 fd = -1;
    147             }
    148         }
    149     }
    150     closedir(dir);
    151     ALOGE_IF(fd<0, "couldn't find '%s' input device", inputName);
    152     return fd;
    153 }
    154