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      1 /*
      2  * Copyright (C) 2014 Intel Corporation
      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 #define LOG_TAG "ThermalManagerJNI"
     18 
     19 #include "JNIHelp.h"
     20 #include "jni.h"
     21 #include <utils/Log.h>
     22 #include <utils/misc.h>
     23 
     24 #include <fcntl.h>
     25 #include <stdio.h>
     26 #include <string.h>
     27 #include <sys/types.h>
     28 #include <stdlib.h>
     29 #include <unistd.h>
     30 
     31 namespace android {
     32 
     33 #define THERMAL_ZONE_PATH "/sys/class/thermal/thermal_zone"
     34 #define COOLING_DEV_PATH  "/sys/class/thermal/cooling_device"
     35 
     36 static int readFromFile(const char *path, char* buf, size_t size, bool throwError)
     37 {
     38     if (!path)
     39         return -1;
     40 
     41     int fd = open(path, O_RDONLY, 0);
     42     if (fd < 0) {
     43         if (throwError) {
     44             ALOGE("Could not open '%s'", path);
     45         }
     46         return -1;
     47     }
     48 
     49     ssize_t count = read(fd, buf, size);
     50     if (count > 0) {
     51         while (count > 0 && buf[count-1] == '\n')
     52             count--;
     53         buf[count] = '\0';
     54     } else {
     55         buf[0] = '\0';
     56     }
     57 
     58     close(fd);
     59     return count;
     60 }
     61 
     62 static int writeToFile(const char *path, int val)
     63 {
     64     const int SIZE = 20;
     65     int ret, fd, len;
     66     char value[SIZE];
     67 
     68     if (!path)
     69         return -1;
     70 
     71     fd = open(path, O_WRONLY, 0);
     72     if (fd < 0) {
     73         ALOGE("writeToFile: Could not open '%s' err: %d", path, errno);
     74         return -1;
     75     }
     76 
     77     len = snprintf(value, SIZE, "%d\n", val);
     78     ret = write(fd, value, len);
     79 
     80     close(fd);
     81     return (ret == len) ? 0 : -1;
     82 }
     83 
     84 static int lookup(const char *base_path, const char *name)
     85 {
     86     const int SIZE = 128;
     87     char buf[SIZE];
     88     char full_path[SIZE];
     89     int count = 0;
     90 
     91     do {
     92         snprintf(full_path, SIZE, "%s%d/type", base_path, count);
     93         // Loop through all thermal_zones or cooling_devices until we
     94         // find a first match. We call it a match when the given
     95         // 'name' of the thermal_zone (or a cooling_device) matches
     96         // with the value of 'type' sysfs interface of a thermal_zone
     97         // (or cooling_device).
     98         if (readFromFile(full_path, buf, SIZE, false) < 0) break;
     99 
    100         if (!strcmp(name, buf)) return count;
    101 
    102         count++;
    103     } while(1);
    104 
    105     // lookup failed.
    106     return -1;
    107 }
    108 
    109 static int lookup_contains(const char *base_path, const char *name)
    110 {
    111     const int SIZE = 128;
    112     char buf[SIZE];
    113     char full_path[SIZE];
    114     int count = 0;
    115 
    116     do {
    117         snprintf(full_path, SIZE, "%s%d/type", base_path, count);
    118         if (readFromFile(full_path, buf, SIZE, false) < 0) break;
    119         // Check if 'buf' contains 'name'
    120         if (strstr(buf, name) != NULL) return count;
    121 
    122         count++;
    123     } while(1);
    124 
    125     // lookup failed.
    126     return -1;
    127 }
    128 
    129 static jboolean isFileExists(JNIEnv* env, jobject obj, jstring jPath)
    130 {
    131     const char *path = NULL;
    132     jboolean ret = true;
    133 
    134     path = jPath ? env->GetStringUTFChars(jPath, NULL) : NULL;
    135     if (!path) {
    136         return false;
    137     }
    138 
    139     int fd = open(path, O_RDONLY, 0);
    140 
    141     if (fd < 0) {
    142         ret = false;
    143     } else {
    144         close(fd);
    145     }
    146     env->ReleaseStringUTFChars(jPath, path);
    147     return ret;
    148 }
    149 
    150 static jint getThermalZoneIndex(JNIEnv* env, jobject obj, jstring jType)
    151 {
    152     int ret;
    153     const char *type = NULL;
    154 
    155     type = jType ? env->GetStringUTFChars(jType, NULL) : NULL;
    156     if (!type) {
    157         jniThrowNullPointerException(env, "Type");
    158         return -1;
    159     }
    160 
    161     ret = lookup(THERMAL_ZONE_PATH, type);
    162     env->ReleaseStringUTFChars(jType, type);
    163     return ret;
    164 }
    165 
    166 static jint getThermalZoneIndexContains(JNIEnv* env, jobject obj, jstring jType)
    167 {
    168     int ret;
    169     const char *type = NULL;
    170 
    171     type = jType ? env->GetStringUTFChars(jType, NULL) : NULL;
    172     if (!type) {
    173         jniThrowNullPointerException(env, "Type");
    174         return -1;
    175     }
    176 
    177     ret = lookup_contains(THERMAL_ZONE_PATH, type);
    178     env->ReleaseStringUTFChars(jType, type);
    179     return ret;
    180 }
    181 
    182 static jint getCoolingDeviceIndex(JNIEnv* env, jobject obj, jstring jType)
    183 {
    184     int ret;
    185     const char *type = NULL;
    186 
    187     type = jType ? env->GetStringUTFChars(jType, NULL) : NULL;
    188     if (!type) {
    189         jniThrowNullPointerException(env, "Type");
    190         return -1;
    191     }
    192 
    193     ret = lookup(COOLING_DEV_PATH, type);
    194     env->ReleaseStringUTFChars(jType, type);
    195     return ret;
    196 }
    197 
    198 static jint getCoolingDeviceIndexContains(JNIEnv* env, jobject obj, jstring jType)
    199 {
    200     int ret;
    201     const char *type = NULL;
    202 
    203     type = jType ? env->GetStringUTFChars(jType, NULL) : NULL;
    204     if (!type) {
    205         jniThrowNullPointerException(env, "Type");
    206         return -1;
    207     }
    208 
    209     ret = lookup_contains(COOLING_DEV_PATH, type);
    210     env->ReleaseStringUTFChars(jType, type);
    211     return ret;
    212 }
    213 
    214 static jint writeSysfs(JNIEnv* env, jobject obj, jstring jPath, jint jVal)
    215 {
    216     int ret;
    217     const char *path = NULL;
    218 
    219     path = jPath ? env->GetStringUTFChars(jPath, NULL) : NULL;
    220     if (!path) {
    221         jniThrowNullPointerException(env, "path");
    222         return -EINVAL;
    223     }
    224 
    225     ret = writeToFile(path, jVal);
    226     env->ReleaseStringUTFChars(jPath, path);
    227     return ret;
    228 }
    229 
    230 static jstring readSysfs(JNIEnv* env, jobject obj, jstring jPath)
    231 {
    232     const char *path = NULL;
    233     const int SIZE = 512;
    234     char buf[SIZE];
    235 
    236     path = jPath ? env->GetStringUTFChars(jPath, NULL) : NULL;
    237     if (!path) {
    238         jniThrowNullPointerException(env, "path");
    239         return NULL;
    240     }
    241 
    242     if (readFromFile(path, buf, SIZE, true) > 0) {
    243         env->ReleaseStringUTFChars(jPath, path);
    244         return env->NewStringUTF(buf);
    245     } else {
    246         env->ReleaseStringUTFChars(jPath, path);
    247         return NULL;
    248     }
    249 }
    250 
    251 static jint readSysfsTemp(JNIEnv* env, jobject obj, jstring jPath)
    252 {
    253     const char *path = NULL;
    254     const int SIZE = 64;
    255     char buf[SIZE];
    256     // Convention: To allow returning of normal negative temperatures
    257     // (say -10C), let us return errno as a negative offset from
    258     // absolute zero millidegree C.
    259     const int ABS_ZERO = -273000;
    260     int ret;
    261 
    262     path = jPath ? env->GetStringUTFChars(jPath, NULL) : NULL;
    263     if (!path) {
    264         jniThrowNullPointerException(env, "path");
    265         return (ABS_ZERO - ENOENT);
    266     }
    267 
    268     ret = readFromFile(path, buf, SIZE, true);
    269     env->ReleaseStringUTFChars(jPath, path);
    270     if (ret > 0) {
    271         return atoi(buf);
    272     }
    273     return (ret + ABS_ZERO);
    274 }
    275 
    276 static JNINativeMethod sMethods[] = {
    277      /* name, signature, funcPtr */
    278         {"native_readSysfs", "(Ljava/lang/String;)Ljava/lang/String;", (void*)readSysfs},
    279         {"native_readSysfsTemp", "(Ljava/lang/String;)I", (void*)readSysfsTemp},
    280         {"native_writeSysfs", "(Ljava/lang/String;I)I", (void*)writeSysfs},
    281         {"native_getThermalZoneIndex", "(Ljava/lang/String;)I", (void*)getThermalZoneIndex},
    282         {"native_getThermalZoneIndexContains", "(Ljava/lang/String;)I",
    283                  (void*)getThermalZoneIndexContains},
    284         {"native_getCoolingDeviceIndex", "(Ljava/lang/String;)I", (void*)getCoolingDeviceIndex},
    285         {"native_getCoolingDeviceIndexContains", "(Ljava/lang/String;)I",
    286                  (void*)getCoolingDeviceIndexContains},
    287         {"native_isFileExists", "(Ljava/lang/String;)Z", (void*)isFileExists},
    288 };
    289 
    290 int register_intel_thermal_ituxd(JNIEnv* env)
    291 {
    292     jclass clazz = env->FindClass("com/intel/thermal/ThermalUtils");
    293     if (clazz == NULL) {
    294         ALOGE("Can't find com/intel/thermal/ThermalUtils");
    295         return -1;
    296     }
    297 
    298     return jniRegisterNativeMethods(env, "com/intel/thermal/ThermalUtils",
    299             sMethods, NELEM(sMethods));
    300 }
    301 
    302 } /* namespace android */
    303