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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 #define UNUSED(expr) (void)(expr)
     37 
     38 static int readFromFile(const char *path, char* buf, size_t size, bool throwError)
     39 {
     40     if (!path)
     41         return -1;
     42 
     43     int fd = open(path, O_RDONLY, 0);
     44     if (fd < 0) {
     45         if (throwError) {
     46             ALOGE("Could not open '%s'", path);
     47         }
     48         return -1;
     49     }
     50 
     51     ssize_t count = read(fd, buf, size);
     52     if (count > 0) {
     53         while (count > 0 && buf[count-1] == '\n')
     54             count--;
     55         buf[count] = '\0';
     56     } else {
     57         buf[0] = '\0';
     58     }
     59 
     60     close(fd);
     61     return count;
     62 }
     63 
     64 static int writeToFile(const char *path, int val)
     65 {
     66     const int SIZE = 20;
     67     int ret, fd, len;
     68     char value[SIZE];
     69 
     70     if (!path)
     71         return -1;
     72 
     73     fd = open(path, O_WRONLY, 0);
     74     if (fd < 0) {
     75         ALOGE("writeToFile: Could not open '%s' err: %d", path, errno);
     76         return -1;
     77     }
     78 
     79     len = snprintf(value, SIZE, "%d\n", val);
     80     ret = write(fd, value, len);
     81 
     82     close(fd);
     83     return (ret == len) ? 0 : -1;
     84 }
     85 
     86 static int lookup(const char *base_path, const char *name)
     87 {
     88     const int SIZE = 128;
     89     char buf[SIZE];
     90     char full_path[SIZE];
     91     int count = 0;
     92 
     93     do {
     94         snprintf(full_path, SIZE, "%s%d/type", base_path, count);
     95         // Loop through all thermal_zones or cooling_devices until we
     96         // find a first match. We call it a match when the given
     97         // 'name' of the thermal_zone (or a cooling_device) matches
     98         // with the value of 'type' sysfs interface of a thermal_zone
     99         // (or cooling_device).
    100         if (readFromFile(full_path, buf, SIZE, false) < 0) break;
    101 
    102         if (!strcmp(name, buf)) return count;
    103 
    104         count++;
    105     } while(1);
    106 
    107     // lookup failed.
    108     return -1;
    109 }
    110 
    111 static int lookup_contains(const char *base_path, const char *name)
    112 {
    113     const int SIZE = 128;
    114     char buf[SIZE];
    115     char full_path[SIZE];
    116     int count = 0;
    117 
    118     do {
    119         snprintf(full_path, SIZE, "%s%d/type", base_path, count);
    120         if (readFromFile(full_path, buf, SIZE, false) < 0) break;
    121         // Check if 'buf' contains 'name'
    122         if (strstr(buf, name) != NULL) return count;
    123 
    124         count++;
    125     } while(1);
    126 
    127     // lookup failed.
    128     return -1;
    129 }
    130 
    131 static jboolean isFileExists(JNIEnv* env, jobject obj, jstring jPath)
    132 {
    133     const char *path = NULL;
    134     jboolean ret = true;
    135     UNUSED(obj);
    136 
    137     path = jPath ? env->GetStringUTFChars(jPath, NULL) : NULL;
    138     if (!path) {
    139         return false;
    140     }
    141 
    142     int fd = open(path, O_RDONLY, 0);
    143 
    144     if (fd < 0) {
    145         ret = false;
    146     } else {
    147         close(fd);
    148     }
    149     env->ReleaseStringUTFChars(jPath, path);
    150     return ret;
    151 }
    152 
    153 static jint getThermalZoneIndex(JNIEnv* env, jobject obj, jstring jType)
    154 {
    155     int ret;
    156     const char *type = NULL;
    157     UNUSED(obj);
    158 
    159     type = jType ? env->GetStringUTFChars(jType, NULL) : NULL;
    160     if (!type) {
    161         jniThrowNullPointerException(env, "Type");
    162         return -1;
    163     }
    164 
    165     ret = lookup(THERMAL_ZONE_PATH, type);
    166     env->ReleaseStringUTFChars(jType, type);
    167     return ret;
    168 }
    169 
    170 static jint getThermalZoneIndexContains(JNIEnv* env, jobject obj, jstring jType)
    171 {
    172     int ret;
    173     const char *type = NULL;
    174     UNUSED(obj);
    175 
    176     type = jType ? env->GetStringUTFChars(jType, NULL) : NULL;
    177     if (!type) {
    178         jniThrowNullPointerException(env, "Type");
    179         return -1;
    180     }
    181 
    182     ret = lookup_contains(THERMAL_ZONE_PATH, type);
    183     env->ReleaseStringUTFChars(jType, type);
    184     return ret;
    185 }
    186 
    187 static jint getCoolingDeviceIndex(JNIEnv* env, jobject obj, jstring jType)
    188 {
    189     int ret;
    190     const char *type = NULL;
    191     UNUSED(obj);
    192 
    193     type = jType ? env->GetStringUTFChars(jType, NULL) : NULL;
    194     if (!type) {
    195         jniThrowNullPointerException(env, "Type");
    196         return -1;
    197     }
    198 
    199     ret = lookup(COOLING_DEV_PATH, type);
    200     env->ReleaseStringUTFChars(jType, type);
    201     return ret;
    202 }
    203 
    204 static jint getCoolingDeviceIndexContains(JNIEnv* env, jobject obj, jstring jType)
    205 {
    206     int ret;
    207     const char *type = NULL;
    208     UNUSED(obj);
    209 
    210     type = jType ? env->GetStringUTFChars(jType, NULL) : NULL;
    211     if (!type) {
    212         jniThrowNullPointerException(env, "Type");
    213         return -1;
    214     }
    215 
    216     ret = lookup_contains(COOLING_DEV_PATH, type);
    217     env->ReleaseStringUTFChars(jType, type);
    218     return ret;
    219 }
    220 
    221 static jint writeSysfs(JNIEnv* env, jobject obj, jstring jPath, jint jVal)
    222 {
    223     int ret;
    224     const char *path = NULL;
    225     UNUSED(obj);
    226 
    227     path = jPath ? env->GetStringUTFChars(jPath, NULL) : NULL;
    228     if (!path) {
    229         jniThrowNullPointerException(env, "path");
    230         return -EINVAL;
    231     }
    232 
    233     ret = writeToFile(path, jVal);
    234     env->ReleaseStringUTFChars(jPath, path);
    235     return ret;
    236 }
    237 
    238 static jstring readSysfs(JNIEnv* env, jobject obj, jstring jPath)
    239 {
    240     const char *path = NULL;
    241     const int SIZE = 512;
    242     char buf[SIZE];
    243     UNUSED(obj);
    244 
    245     path = jPath ? env->GetStringUTFChars(jPath, NULL) : NULL;
    246     if (!path) {
    247         jniThrowNullPointerException(env, "path");
    248         return NULL;
    249     }
    250 
    251     if (readFromFile(path, buf, SIZE, true) > 0) {
    252         env->ReleaseStringUTFChars(jPath, path);
    253         return env->NewStringUTF(buf);
    254     } else {
    255         env->ReleaseStringUTFChars(jPath, path);
    256         return NULL;
    257     }
    258 }
    259 
    260 static jint readSysfsTemp(JNIEnv* env, jobject obj, jstring jPath)
    261 {
    262     const char *path = NULL;
    263     const int SIZE = 64;
    264     char buf[SIZE];
    265     // Convention: To allow returning of normal negative temperatures
    266     // (say -10C), let us return errno as a negative offset from
    267     // absolute zero millidegree C.
    268     const int ABS_ZERO = -273000;
    269     int ret;
    270     UNUSED(obj);
    271 
    272     path = jPath ? env->GetStringUTFChars(jPath, NULL) : NULL;
    273     if (!path) {
    274         jniThrowNullPointerException(env, "path");
    275         return (ABS_ZERO - ENOENT);
    276     }
    277 
    278     ret = readFromFile(path, buf, SIZE, true);
    279     env->ReleaseStringUTFChars(jPath, path);
    280     if (ret > 0) {
    281         return atoi(buf);
    282     }
    283     return (ret + ABS_ZERO);
    284 }
    285 
    286 static JNINativeMethod sMethods[] = {
    287      /* name, signature, funcPtr */
    288         {"native_readSysfs", "(Ljava/lang/String;)Ljava/lang/String;", (void*)readSysfs},
    289         {"native_readSysfsTemp", "(Ljava/lang/String;)I", (void*)readSysfsTemp},
    290         {"native_writeSysfs", "(Ljava/lang/String;I)I", (void*)writeSysfs},
    291         {"native_getThermalZoneIndex", "(Ljava/lang/String;)I", (void*)getThermalZoneIndex},
    292         {"native_getThermalZoneIndexContains", "(Ljava/lang/String;)I",
    293                  (void*)getThermalZoneIndexContains},
    294         {"native_getCoolingDeviceIndex", "(Ljava/lang/String;)I", (void*)getCoolingDeviceIndex},
    295         {"native_getCoolingDeviceIndexContains", "(Ljava/lang/String;)I",
    296                  (void*)getCoolingDeviceIndexContains},
    297         {"native_isFileExists", "(Ljava/lang/String;)Z", (void*)isFileExists},
    298 };
    299 
    300 int register_intel_thermal_ituxd(JNIEnv* env)
    301 {
    302     jclass clazz = env->FindClass("com/intel/thermal/ThermalUtils");
    303     if (clazz == NULL) {
    304         ALOGE("Can't find com/intel/thermal/ThermalUtils");
    305         return -1;
    306     }
    307 
    308     return jniRegisterNativeMethods(env, "com/intel/thermal/ThermalUtils",
    309             sMethods, NELEM(sMethods));
    310 }
    311 
    312 } /* namespace android */
    313