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      1 /* //device/libs/android_runtime/android_util_Process.cpp
      2 **
      3 ** Copyright 2006, The Android Open Source Project
      4 **
      5 ** Licensed under the Apache License, Version 2.0 (the "License");
      6 ** you may not use this file except in compliance with the License.
      7 ** You may obtain a copy of the License at
      8 **
      9 **     http://www.apache.org/licenses/LICENSE-2.0
     10 **
     11 ** Unless required by applicable law or agreed to in writing, software
     12 ** distributed under the License is distributed on an "AS IS" BASIS,
     13 ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     14 ** See the License for the specific language governing permissions and
     15 ** limitations under the License.
     16 */
     17 
     18 #define LOG_TAG "Process"
     19 
     20 // To make sure cpu_set_t is included from sched.h
     21 #define _GNU_SOURCE 1
     22 #include <utils/Log.h>
     23 #include <binder/IPCThreadState.h>
     24 #include <binder/IServiceManager.h>
     25 #include <cutils/sched_policy.h>
     26 #include <utils/String8.h>
     27 #include <utils/Vector.h>
     28 #include <processgroup/processgroup.h>
     29 
     30 #include "core_jni_helpers.h"
     31 
     32 #include "android_util_Binder.h"
     33 #include <nativehelper/JNIHelp.h>
     34 #include "android_os_Debug.h"
     35 
     36 #include <dirent.h>
     37 #include <fcntl.h>
     38 #include <grp.h>
     39 #include <inttypes.h>
     40 #include <pwd.h>
     41 #include <signal.h>
     42 #include <sys/errno.h>
     43 #include <sys/resource.h>
     44 #include <sys/stat.h>
     45 #include <sys/types.h>
     46 #include <unistd.h>
     47 
     48 #define GUARD_THREAD_PRIORITY 0
     49 
     50 using namespace android;
     51 
     52 static const bool kDebugPolicy = false;
     53 static const bool kDebugProc = false;
     54 
     55 #if GUARD_THREAD_PRIORITY
     56 Mutex gKeyCreateMutex;
     57 static pthread_key_t gBgKey = -1;
     58 #endif
     59 
     60 // For both of these, err should be in the errno range (positive), not a status_t (negative)
     61 static void signalExceptionForError(JNIEnv* env, int err, int tid) {
     62     switch (err) {
     63         case EINVAL:
     64             jniThrowExceptionFmt(env, "java/lang/IllegalArgumentException",
     65                                  "Invalid argument: %d", tid);
     66             break;
     67         case ESRCH:
     68             jniThrowExceptionFmt(env, "java/lang/IllegalArgumentException",
     69                                  "Given thread %d does not exist", tid);
     70             break;
     71         case EPERM:
     72             jniThrowExceptionFmt(env, "java/lang/SecurityException",
     73                                  "No permission to modify given thread %d", tid);
     74             break;
     75         default:
     76             jniThrowException(env, "java/lang/RuntimeException", "Unknown error");
     77             break;
     78     }
     79 }
     80 
     81 static void signalExceptionForPriorityError(JNIEnv* env, int err, int tid) {
     82     switch (err) {
     83         case EACCES:
     84             jniThrowExceptionFmt(env, "java/lang/SecurityException",
     85                                  "No permission to set the priority of %d", tid);
     86             break;
     87         default:
     88             signalExceptionForError(env, err, tid);
     89             break;
     90     }
     91 
     92 }
     93 
     94 static void signalExceptionForGroupError(JNIEnv* env, int err, int tid) {
     95     switch (err) {
     96         case EACCES:
     97             jniThrowExceptionFmt(env, "java/lang/SecurityException",
     98                                  "No permission to set the group of %d", tid);
     99             break;
    100         default:
    101             signalExceptionForError(env, err, tid);
    102             break;
    103     }
    104 }
    105 
    106 jint android_os_Process_getUidForName(JNIEnv* env, jobject clazz, jstring name)
    107 {
    108     if (name == NULL) {
    109         jniThrowNullPointerException(env, NULL);
    110         return -1;
    111     }
    112 
    113     const jchar* str16 = env->GetStringCritical(name, 0);
    114     String8 name8;
    115     if (str16) {
    116         name8 = String8(reinterpret_cast<const char16_t*>(str16),
    117                         env->GetStringLength(name));
    118         env->ReleaseStringCritical(name, str16);
    119     }
    120 
    121     const size_t N = name8.size();
    122     if (N > 0) {
    123         const char* str = name8.string();
    124         for (size_t i=0; i<N; i++) {
    125             if (str[i] < '0' || str[i] > '9') {
    126                 struct passwd* pwd = getpwnam(str);
    127                 if (pwd == NULL) {
    128                     return -1;
    129                 }
    130                 return pwd->pw_uid;
    131             }
    132         }
    133         return atoi(str);
    134     }
    135     return -1;
    136 }
    137 
    138 jint android_os_Process_getGidForName(JNIEnv* env, jobject clazz, jstring name)
    139 {
    140     if (name == NULL) {
    141         jniThrowNullPointerException(env, NULL);
    142         return -1;
    143     }
    144 
    145     const jchar* str16 = env->GetStringCritical(name, 0);
    146     String8 name8;
    147     if (str16) {
    148         name8 = String8(reinterpret_cast<const char16_t*>(str16),
    149                         env->GetStringLength(name));
    150         env->ReleaseStringCritical(name, str16);
    151     }
    152 
    153     const size_t N = name8.size();
    154     if (N > 0) {
    155         const char* str = name8.string();
    156         for (size_t i=0; i<N; i++) {
    157             if (str[i] < '0' || str[i] > '9') {
    158                 struct group* grp = getgrnam(str);
    159                 if (grp == NULL) {
    160                     return -1;
    161                 }
    162                 return grp->gr_gid;
    163             }
    164         }
    165         return atoi(str);
    166     }
    167     return -1;
    168 }
    169 
    170 void android_os_Process_setThreadGroup(JNIEnv* env, jobject clazz, int tid, jint grp)
    171 {
    172     ALOGV("%s tid=%d grp=%" PRId32, __func__, tid, grp);
    173     SchedPolicy sp = (SchedPolicy) grp;
    174     int res = set_sched_policy(tid, sp);
    175     if (res != NO_ERROR) {
    176         signalExceptionForGroupError(env, -res, tid);
    177     }
    178 }
    179 
    180 void android_os_Process_setThreadGroupAndCpuset(JNIEnv* env, jobject clazz, int tid, jint grp)
    181 {
    182     ALOGV("%s tid=%d grp=%" PRId32, __func__, tid, grp);
    183     SchedPolicy sp = (SchedPolicy) grp;
    184     int res = set_sched_policy(tid, sp);
    185 
    186     if (res != NO_ERROR) {
    187         signalExceptionForGroupError(env, -res, tid);
    188     }
    189 
    190     res = set_cpuset_policy(tid, sp);
    191     if (res != NO_ERROR) {
    192         signalExceptionForGroupError(env, -res, tid);
    193     }
    194 }
    195 
    196 void android_os_Process_setProcessGroup(JNIEnv* env, jobject clazz, int pid, jint grp)
    197 {
    198     ALOGV("%s pid=%d grp=%" PRId32, __func__, pid, grp);
    199     DIR *d;
    200     char proc_path[255];
    201     struct dirent *de;
    202 
    203     if ((grp == SP_FOREGROUND) || (grp > SP_MAX)) {
    204         signalExceptionForGroupError(env, EINVAL, pid);
    205         return;
    206     }
    207 
    208     bool isDefault = false;
    209     if (grp < 0) {
    210         grp = SP_FOREGROUND;
    211         isDefault = true;
    212     }
    213     SchedPolicy sp = (SchedPolicy) grp;
    214 
    215     if (kDebugPolicy) {
    216         char cmdline[32];
    217         int fd;
    218 
    219         strcpy(cmdline, "unknown");
    220 
    221         sprintf(proc_path, "/proc/%d/cmdline", pid);
    222         fd = open(proc_path, O_RDONLY | O_CLOEXEC);
    223         if (fd >= 0) {
    224             int rc = read(fd, cmdline, sizeof(cmdline)-1);
    225             cmdline[rc] = 0;
    226             close(fd);
    227         }
    228 
    229         if (sp == SP_BACKGROUND) {
    230             ALOGD("setProcessGroup: vvv pid %d (%s)", pid, cmdline);
    231         } else {
    232             ALOGD("setProcessGroup: ^^^ pid %d (%s)", pid, cmdline);
    233         }
    234     }
    235 
    236     sprintf(proc_path, "/proc/%d/task", pid);
    237     if (!(d = opendir(proc_path))) {
    238         // If the process exited on us, don't generate an exception
    239         if (errno != ENOENT)
    240             signalExceptionForGroupError(env, errno, pid);
    241         return;
    242     }
    243 
    244     while ((de = readdir(d))) {
    245         int t_pid;
    246         int t_pri;
    247 
    248         if (de->d_name[0] == '.')
    249             continue;
    250         t_pid = atoi(de->d_name);
    251 
    252         if (!t_pid) {
    253             ALOGE("Error getting pid for '%s'\n", de->d_name);
    254             continue;
    255         }
    256 
    257         t_pri = getpriority(PRIO_PROCESS, t_pid);
    258 
    259         if (t_pri <= ANDROID_PRIORITY_AUDIO) {
    260             int scheduler = sched_getscheduler(t_pid) & ~SCHED_RESET_ON_FORK;
    261             if ((scheduler == SCHED_FIFO) || (scheduler == SCHED_RR)) {
    262                 // This task wants to stay in its current audio group so it can keep its budget
    263                 // don't update its cpuset or cgroup
    264                 continue;
    265             }
    266         }
    267 
    268         if (isDefault) {
    269             if (t_pri >= ANDROID_PRIORITY_BACKGROUND) {
    270                 // This task wants to stay at background
    271                 // update its cpuset so it doesn't only run on bg core(s)
    272                 if (cpusets_enabled()) {
    273                     int err = set_cpuset_policy(t_pid, sp);
    274                     if (err != NO_ERROR) {
    275                         signalExceptionForGroupError(env, -err, t_pid);
    276                         break;
    277                     }
    278                 }
    279                 continue;
    280             }
    281         }
    282         int err;
    283 
    284         if (cpusets_enabled()) {
    285             // set both cpuset and cgroup for general threads
    286             err = set_cpuset_policy(t_pid, sp);
    287             if (err != NO_ERROR) {
    288                 signalExceptionForGroupError(env, -err, t_pid);
    289                 break;
    290             }
    291         }
    292 
    293         err = set_sched_policy(t_pid, sp);
    294         if (err != NO_ERROR) {
    295             signalExceptionForGroupError(env, -err, t_pid);
    296             break;
    297         }
    298 
    299     }
    300     closedir(d);
    301 }
    302 
    303 jint android_os_Process_getProcessGroup(JNIEnv* env, jobject clazz, jint pid)
    304 {
    305     SchedPolicy sp;
    306     if (get_sched_policy(pid, &sp) != 0) {
    307         signalExceptionForGroupError(env, errno, pid);
    308     }
    309     return (int) sp;
    310 }
    311 
    312 /** Sample CPUset list format:
    313  *  0-3,4,6-8
    314  */
    315 static void parse_cpuset_cpus(char *cpus, cpu_set_t *cpu_set) {
    316     unsigned int start, end, matched, i;
    317     char *cpu_range = strtok(cpus, ",");
    318     while (cpu_range != NULL) {
    319         start = end = 0;
    320         matched = sscanf(cpu_range, "%u-%u", &start, &end);
    321         cpu_range = strtok(NULL, ",");
    322         if (start >= CPU_SETSIZE) {
    323             ALOGE("parse_cpuset_cpus: ignoring CPU number larger than %d.", CPU_SETSIZE);
    324             continue;
    325         } else if (end >= CPU_SETSIZE) {
    326             ALOGE("parse_cpuset_cpus: ignoring CPU numbers larger than %d.", CPU_SETSIZE);
    327             end = CPU_SETSIZE - 1;
    328         }
    329         if (matched == 1) {
    330             CPU_SET(start, cpu_set);
    331         } else if (matched == 2) {
    332             for (i = start; i <= end; i++) {
    333                 CPU_SET(i, cpu_set);
    334             }
    335         } else {
    336             ALOGE("Failed to match cpus");
    337         }
    338     }
    339     return;
    340 }
    341 
    342 /**
    343  * Stores the CPUs assigned to the cpuset corresponding to the
    344  * SchedPolicy in the passed in cpu_set.
    345  */
    346 static void get_cpuset_cores_for_policy(SchedPolicy policy, cpu_set_t *cpu_set)
    347 {
    348     FILE *file;
    349     const char *filename;
    350 
    351     CPU_ZERO(cpu_set);
    352 
    353     switch (policy) {
    354         case SP_BACKGROUND:
    355             filename = "/dev/cpuset/background/cpus";
    356             break;
    357         case SP_FOREGROUND:
    358         case SP_AUDIO_APP:
    359         case SP_AUDIO_SYS:
    360         case SP_RT_APP:
    361             filename = "/dev/cpuset/foreground/cpus";
    362             break;
    363         case SP_TOP_APP:
    364             filename = "/dev/cpuset/top-app/cpus";
    365             break;
    366         default:
    367             filename = NULL;
    368     }
    369 
    370     if (!filename) return;
    371 
    372     file = fopen(filename, "re");
    373     if (file != NULL) {
    374         // Parse cpus string
    375         char *line = NULL;
    376         size_t len = 0;
    377         ssize_t num_read = getline(&line, &len, file);
    378         fclose (file);
    379         if (num_read > 0) {
    380             parse_cpuset_cpus(line, cpu_set);
    381         } else {
    382             ALOGE("Failed to read %s", filename);
    383         }
    384         free(line);
    385     }
    386     return;
    387 }
    388 
    389 
    390 /**
    391  * Determine CPU cores exclusively assigned to the
    392  * cpuset corresponding to the SchedPolicy and store
    393  * them in the passed in cpu_set_t
    394  */
    395 void get_exclusive_cpuset_cores(SchedPolicy policy, cpu_set_t *cpu_set) {
    396     if (cpusets_enabled()) {
    397         int i;
    398         cpu_set_t tmp_set;
    399         get_cpuset_cores_for_policy(policy, cpu_set);
    400         for (i = 0; i < SP_CNT; i++) {
    401             if ((SchedPolicy) i == policy) continue;
    402             get_cpuset_cores_for_policy((SchedPolicy)i, &tmp_set);
    403             // First get cores exclusive to one set or the other
    404             CPU_XOR(&tmp_set, cpu_set, &tmp_set);
    405             // Then get the ones only in cpu_set
    406             CPU_AND(cpu_set, cpu_set, &tmp_set);
    407         }
    408     } else {
    409         CPU_ZERO(cpu_set);
    410     }
    411     return;
    412 }
    413 
    414 jintArray android_os_Process_getExclusiveCores(JNIEnv* env, jobject clazz) {
    415     SchedPolicy sp;
    416     cpu_set_t cpu_set;
    417     jintArray cpus;
    418     int pid = getpid();
    419     if (get_sched_policy(pid, &sp) != 0) {
    420         signalExceptionForGroupError(env, errno, pid);
    421         return NULL;
    422     }
    423     get_exclusive_cpuset_cores(sp, &cpu_set);
    424     int num_cpus = CPU_COUNT(&cpu_set);
    425     cpus = env->NewIntArray(num_cpus);
    426     if (cpus == NULL) {
    427         jniThrowException(env, "java/lang/OutOfMemoryError", NULL);
    428         return NULL;
    429     }
    430 
    431     jint* cpu_elements = env->GetIntArrayElements(cpus, 0);
    432     int count = 0;
    433     for (int i = 0; i < CPU_SETSIZE && count < num_cpus; i++) {
    434         if (CPU_ISSET(i, &cpu_set)) {
    435             cpu_elements[count++] = i;
    436         }
    437     }
    438 
    439     env->ReleaseIntArrayElements(cpus, cpu_elements, 0);
    440     return cpus;
    441 }
    442 
    443 static void android_os_Process_setCanSelfBackground(JNIEnv* env, jobject clazz, jboolean bgOk) {
    444     // Establishes the calling thread as illegal to put into the background.
    445     // Typically used only for the system process's main looper.
    446 #if GUARD_THREAD_PRIORITY
    447     ALOGV("Process.setCanSelfBackground(%d) : tid=%d", bgOk, gettid());
    448     {
    449         Mutex::Autolock _l(gKeyCreateMutex);
    450         if (gBgKey == -1) {
    451             pthread_key_create(&gBgKey, NULL);
    452         }
    453     }
    454 
    455     // inverted:  not-okay, we set a sentinel value
    456     pthread_setspecific(gBgKey, (void*)(bgOk ? 0 : 0xbaad));
    457 #endif
    458 }
    459 
    460 jint android_os_Process_getThreadScheduler(JNIEnv* env, jclass clazz,
    461                                               jint tid)
    462 {
    463     int policy = 0;
    464 // linux has sched_getscheduler(), others don't.
    465 #if defined(__linux__)
    466     errno = 0;
    467     policy = sched_getscheduler(tid);
    468     if (errno != 0) {
    469         signalExceptionForPriorityError(env, errno, tid);
    470     }
    471 #else
    472     signalExceptionForPriorityError(env, ENOSYS, tid);
    473 #endif
    474     return policy;
    475 }
    476 
    477 void android_os_Process_setThreadScheduler(JNIEnv* env, jclass clazz,
    478                                               jint tid, jint policy, jint pri)
    479 {
    480 // linux has sched_setscheduler(), others don't.
    481 #if defined(__linux__)
    482     struct sched_param param;
    483     param.sched_priority = pri;
    484     int rc = sched_setscheduler(tid, policy, &param);
    485     if (rc) {
    486         signalExceptionForPriorityError(env, errno, tid);
    487     }
    488 #else
    489     signalExceptionForPriorityError(env, ENOSYS, tid);
    490 #endif
    491 }
    492 
    493 void android_os_Process_setThreadPriority(JNIEnv* env, jobject clazz,
    494                                               jint pid, jint pri)
    495 {
    496 #if GUARD_THREAD_PRIORITY
    497     // if we're putting the current thread into the background, check the TLS
    498     // to make sure this thread isn't guarded.  If it is, raise an exception.
    499     if (pri >= ANDROID_PRIORITY_BACKGROUND) {
    500         if (pid == gettid()) {
    501             void* bgOk = pthread_getspecific(gBgKey);
    502             if (bgOk == ((void*)0xbaad)) {
    503                 ALOGE("Thread marked fg-only put self in background!");
    504                 jniThrowException(env, "java/lang/SecurityException", "May not put this thread into background");
    505                 return;
    506             }
    507         }
    508     }
    509 #endif
    510 
    511     int rc = androidSetThreadPriority(pid, pri);
    512     if (rc != 0) {
    513         if (rc == INVALID_OPERATION) {
    514             signalExceptionForPriorityError(env, errno, pid);
    515         } else {
    516             signalExceptionForGroupError(env, errno, pid);
    517         }
    518     }
    519 
    520     //ALOGI("Setting priority of %" PRId32 ": %" PRId32 ", getpriority returns %d\n",
    521     //     pid, pri, getpriority(PRIO_PROCESS, pid));
    522 }
    523 
    524 void android_os_Process_setCallingThreadPriority(JNIEnv* env, jobject clazz,
    525                                                         jint pri)
    526 {
    527     android_os_Process_setThreadPriority(env, clazz, gettid(), pri);
    528 }
    529 
    530 jint android_os_Process_getThreadPriority(JNIEnv* env, jobject clazz,
    531                                               jint pid)
    532 {
    533     errno = 0;
    534     jint pri = getpriority(PRIO_PROCESS, pid);
    535     if (errno != 0) {
    536         signalExceptionForPriorityError(env, errno, pid);
    537     }
    538     //ALOGI("Returning priority of %" PRId32 ": %" PRId32 "\n", pid, pri);
    539     return pri;
    540 }
    541 
    542 jboolean android_os_Process_setSwappiness(JNIEnv *env, jobject clazz,
    543                                           jint pid, jboolean is_increased)
    544 {
    545     char text[64];
    546 
    547     if (is_increased) {
    548         strcpy(text, "/sys/fs/cgroup/memory/sw/tasks");
    549     } else {
    550         strcpy(text, "/sys/fs/cgroup/memory/tasks");
    551     }
    552 
    553     struct stat st;
    554     if (stat(text, &st) || !S_ISREG(st.st_mode)) {
    555         return false;
    556     }
    557 
    558     int fd = open(text, O_WRONLY | O_CLOEXEC);
    559     if (fd >= 0) {
    560         sprintf(text, "%" PRId32, pid);
    561         write(fd, text, strlen(text));
    562         close(fd);
    563     }
    564 
    565     return true;
    566 }
    567 
    568 void android_os_Process_setArgV0(JNIEnv* env, jobject clazz, jstring name)
    569 {
    570     if (name == NULL) {
    571         jniThrowNullPointerException(env, NULL);
    572         return;
    573     }
    574 
    575     const jchar* str = env->GetStringCritical(name, 0);
    576     String8 name8;
    577     if (str) {
    578         name8 = String8(reinterpret_cast<const char16_t*>(str),
    579                         env->GetStringLength(name));
    580         env->ReleaseStringCritical(name, str);
    581     }
    582 
    583     if (!name8.isEmpty()) {
    584         AndroidRuntime::getRuntime()->setArgv0(name8.string(), true /* setProcName */);
    585     }
    586 }
    587 
    588 jint android_os_Process_setUid(JNIEnv* env, jobject clazz, jint uid)
    589 {
    590     return setuid(uid) == 0 ? 0 : errno;
    591 }
    592 
    593 jint android_os_Process_setGid(JNIEnv* env, jobject clazz, jint uid)
    594 {
    595     return setgid(uid) == 0 ? 0 : errno;
    596 }
    597 
    598 static int pid_compare(const void* v1, const void* v2)
    599 {
    600     //ALOGI("Compare %" PRId32 " vs %" PRId32 "\n", *((const jint*)v1), *((const jint*)v2));
    601     return *((const jint*)v1) - *((const jint*)v2);
    602 }
    603 
    604 static jlong getFreeMemoryImpl(const char* const sums[], const size_t sumsLen[], size_t num)
    605 {
    606     int fd = open("/proc/meminfo", O_RDONLY | O_CLOEXEC);
    607 
    608     if (fd < 0) {
    609         ALOGW("Unable to open /proc/meminfo");
    610         return -1;
    611     }
    612 
    613     char buffer[2048];
    614     const int len = read(fd, buffer, sizeof(buffer)-1);
    615     close(fd);
    616 
    617     if (len < 0) {
    618         ALOGW("Unable to read /proc/meminfo");
    619         return -1;
    620     }
    621     buffer[len] = 0;
    622 
    623     size_t numFound = 0;
    624     jlong mem = 0;
    625 
    626     char* p = buffer;
    627     while (*p && numFound < num) {
    628         int i = 0;
    629         while (sums[i]) {
    630             if (strncmp(p, sums[i], sumsLen[i]) == 0) {
    631                 p += sumsLen[i];
    632                 while (*p == ' ') p++;
    633                 char* num = p;
    634                 while (*p >= '0' && *p <= '9') p++;
    635                 if (*p != 0) {
    636                     *p = 0;
    637                     p++;
    638                     if (*p == 0) p--;
    639                 }
    640                 mem += atoll(num) * 1024;
    641                 numFound++;
    642                 break;
    643             }
    644             i++;
    645         }
    646         p++;
    647     }
    648 
    649     return numFound > 0 ? mem : -1;
    650 }
    651 
    652 static jlong android_os_Process_getFreeMemory(JNIEnv* env, jobject clazz)
    653 {
    654     static const char* const sums[] = { "MemFree:", "Cached:", NULL };
    655     static const size_t sumsLen[] = { strlen("MemFree:"), strlen("Cached:"), 0 };
    656     return getFreeMemoryImpl(sums, sumsLen, 2);
    657 }
    658 
    659 static jlong android_os_Process_getTotalMemory(JNIEnv* env, jobject clazz)
    660 {
    661     static const char* const sums[] = { "MemTotal:", NULL };
    662     static const size_t sumsLen[] = { strlen("MemTotal:"), 0 };
    663     return getFreeMemoryImpl(sums, sumsLen, 1);
    664 }
    665 
    666 void android_os_Process_readProcLines(JNIEnv* env, jobject clazz, jstring fileStr,
    667                                       jobjectArray reqFields, jlongArray outFields)
    668 {
    669     //ALOGI("getMemInfo: %p %p", reqFields, outFields);
    670 
    671     if (fileStr == NULL || reqFields == NULL || outFields == NULL) {
    672         jniThrowNullPointerException(env, NULL);
    673         return;
    674     }
    675 
    676     const char* file8 = env->GetStringUTFChars(fileStr, NULL);
    677     if (file8 == NULL) {
    678         return;
    679     }
    680     String8 file(file8);
    681     env->ReleaseStringUTFChars(fileStr, file8);
    682 
    683     jsize count = env->GetArrayLength(reqFields);
    684     if (count > env->GetArrayLength(outFields)) {
    685         jniThrowException(env, "java/lang/IllegalArgumentException", "Array lengths differ");
    686         return;
    687     }
    688 
    689     Vector<String8> fields;
    690     int i;
    691 
    692     for (i=0; i<count; i++) {
    693         jobject obj = env->GetObjectArrayElement(reqFields, i);
    694         if (obj != NULL) {
    695             const char* str8 = env->GetStringUTFChars((jstring)obj, NULL);
    696             //ALOGI("String at %d: %p = %s", i, obj, str8);
    697             if (str8 == NULL) {
    698                 jniThrowNullPointerException(env, "Element in reqFields");
    699                 return;
    700             }
    701             fields.add(String8(str8));
    702             env->ReleaseStringUTFChars((jstring)obj, str8);
    703         } else {
    704             jniThrowNullPointerException(env, "Element in reqFields");
    705             return;
    706         }
    707     }
    708 
    709     jlong* sizesArray = env->GetLongArrayElements(outFields, 0);
    710     if (sizesArray == NULL) {
    711         return;
    712     }
    713 
    714     //ALOGI("Clearing %" PRId32 " sizes", count);
    715     for (i=0; i<count; i++) {
    716         sizesArray[i] = 0;
    717     }
    718 
    719     int fd = open(file.string(), O_RDONLY | O_CLOEXEC);
    720 
    721     if (fd >= 0) {
    722         const size_t BUFFER_SIZE = 4096;
    723         char* buffer = (char*)malloc(BUFFER_SIZE);
    724         int len = read(fd, buffer, BUFFER_SIZE-1);
    725         close(fd);
    726 
    727         if (len < 0) {
    728             ALOGW("Unable to read %s", file.string());
    729             len = 0;
    730         }
    731         buffer[len] = 0;
    732 
    733         int foundCount = 0;
    734 
    735         char* p = buffer;
    736         while (*p && foundCount < count) {
    737             bool skipToEol = true;
    738             //ALOGI("Parsing at: %s", p);
    739             for (i=0; i<count; i++) {
    740                 const String8& field = fields[i];
    741                 if (strncmp(p, field.string(), field.length()) == 0) {
    742                     p += field.length();
    743                     while (*p == ' ' || *p == '\t') p++;
    744                     char* num = p;
    745                     while (*p >= '0' && *p <= '9') p++;
    746                     skipToEol = *p != '\n';
    747                     if (*p != 0) {
    748                         *p = 0;
    749                         p++;
    750                     }
    751                     char* end;
    752                     sizesArray[i] = strtoll(num, &end, 10);
    753                     //ALOGI("Field %s = %" PRId64, field.string(), sizesArray[i]);
    754                     foundCount++;
    755                     break;
    756                 }
    757             }
    758             if (skipToEol) {
    759                 while (*p && *p != '\n') {
    760                     p++;
    761                 }
    762                 if (*p == '\n') {
    763                     p++;
    764                 }
    765             }
    766         }
    767 
    768         free(buffer);
    769     } else {
    770         ALOGW("Unable to open %s", file.string());
    771     }
    772 
    773     //ALOGI("Done!");
    774     env->ReleaseLongArrayElements(outFields, sizesArray, 0);
    775 }
    776 
    777 jintArray android_os_Process_getPids(JNIEnv* env, jobject clazz,
    778                                      jstring file, jintArray lastArray)
    779 {
    780     if (file == NULL) {
    781         jniThrowNullPointerException(env, NULL);
    782         return NULL;
    783     }
    784 
    785     const char* file8 = env->GetStringUTFChars(file, NULL);
    786     if (file8 == NULL) {
    787         jniThrowException(env, "java/lang/OutOfMemoryError", NULL);
    788         return NULL;
    789     }
    790 
    791     DIR* dirp = opendir(file8);
    792 
    793     env->ReleaseStringUTFChars(file, file8);
    794 
    795     if(dirp == NULL) {
    796         return NULL;
    797     }
    798 
    799     jsize curCount = 0;
    800     jint* curData = NULL;
    801     if (lastArray != NULL) {
    802         curCount = env->GetArrayLength(lastArray);
    803         curData = env->GetIntArrayElements(lastArray, 0);
    804     }
    805 
    806     jint curPos = 0;
    807 
    808     struct dirent* entry;
    809     while ((entry=readdir(dirp)) != NULL) {
    810         const char* p = entry->d_name;
    811         while (*p) {
    812             if (*p < '0' || *p > '9') break;
    813             p++;
    814         }
    815         if (*p != 0) continue;
    816 
    817         char* end;
    818         int pid = strtol(entry->d_name, &end, 10);
    819         //ALOGI("File %s pid=%d\n", entry->d_name, pid);
    820         if (curPos >= curCount) {
    821             jsize newCount = (curCount == 0) ? 10 : (curCount*2);
    822             jintArray newArray = env->NewIntArray(newCount);
    823             if (newArray == NULL) {
    824                 closedir(dirp);
    825                 jniThrowException(env, "java/lang/OutOfMemoryError", NULL);
    826                 return NULL;
    827             }
    828             jint* newData = env->GetIntArrayElements(newArray, 0);
    829             if (curData != NULL) {
    830                 memcpy(newData, curData, sizeof(jint)*curCount);
    831                 env->ReleaseIntArrayElements(lastArray, curData, 0);
    832             }
    833             lastArray = newArray;
    834             curCount = newCount;
    835             curData = newData;
    836         }
    837 
    838         curData[curPos] = pid;
    839         curPos++;
    840     }
    841 
    842     closedir(dirp);
    843 
    844     if (curData != NULL && curPos > 0) {
    845         qsort(curData, curPos, sizeof(jint), pid_compare);
    846     }
    847 
    848     while (curPos < curCount) {
    849         curData[curPos] = -1;
    850         curPos++;
    851     }
    852 
    853     if (curData != NULL) {
    854         env->ReleaseIntArrayElements(lastArray, curData, 0);
    855     }
    856 
    857     return lastArray;
    858 }
    859 
    860 enum {
    861     PROC_TERM_MASK = 0xff,
    862     PROC_ZERO_TERM = 0,
    863     PROC_SPACE_TERM = ' ',
    864     PROC_COMBINE = 0x100,
    865     PROC_PARENS = 0x200,
    866     PROC_QUOTES = 0x400,
    867     PROC_CHAR = 0x800,
    868     PROC_OUT_STRING = 0x1000,
    869     PROC_OUT_LONG = 0x2000,
    870     PROC_OUT_FLOAT = 0x4000,
    871 };
    872 
    873 jboolean android_os_Process_parseProcLineArray(JNIEnv* env, jobject clazz,
    874         char* buffer, jint startIndex, jint endIndex, jintArray format,
    875         jobjectArray outStrings, jlongArray outLongs, jfloatArray outFloats)
    876 {
    877 
    878     const jsize NF = env->GetArrayLength(format);
    879     const jsize NS = outStrings ? env->GetArrayLength(outStrings) : 0;
    880     const jsize NL = outLongs ? env->GetArrayLength(outLongs) : 0;
    881     const jsize NR = outFloats ? env->GetArrayLength(outFloats) : 0;
    882 
    883     jint* formatData = env->GetIntArrayElements(format, 0);
    884     jlong* longsData = outLongs ?
    885         env->GetLongArrayElements(outLongs, 0) : NULL;
    886     jfloat* floatsData = outFloats ?
    887         env->GetFloatArrayElements(outFloats, 0) : NULL;
    888     if (formatData == NULL || (NL > 0 && longsData == NULL)
    889             || (NR > 0 && floatsData == NULL)) {
    890         if (formatData != NULL) {
    891             env->ReleaseIntArrayElements(format, formatData, 0);
    892         }
    893         if (longsData != NULL) {
    894             env->ReleaseLongArrayElements(outLongs, longsData, 0);
    895         }
    896         if (floatsData != NULL) {
    897             env->ReleaseFloatArrayElements(outFloats, floatsData, 0);
    898         }
    899         jniThrowException(env, "java/lang/OutOfMemoryError", NULL);
    900         return JNI_FALSE;
    901     }
    902 
    903     jsize i = startIndex;
    904     jsize di = 0;
    905 
    906     jboolean res = JNI_TRUE;
    907 
    908     for (jsize fi=0; fi<NF; fi++) {
    909         jint mode = formatData[fi];
    910         if ((mode&PROC_PARENS) != 0) {
    911             i++;
    912         } else if ((mode&PROC_QUOTES) != 0) {
    913             if (buffer[i] == '"') {
    914                 i++;
    915             } else {
    916                 mode &= ~PROC_QUOTES;
    917             }
    918         }
    919         const char term = (char)(mode&PROC_TERM_MASK);
    920         const jsize start = i;
    921         if (i >= endIndex) {
    922             if (kDebugProc) {
    923                 ALOGW("Ran off end of data @%d", i);
    924             }
    925             res = JNI_FALSE;
    926             break;
    927         }
    928 
    929         jsize end = -1;
    930         if ((mode&PROC_PARENS) != 0) {
    931             while (i < endIndex && buffer[i] != ')') {
    932                 i++;
    933             }
    934             end = i;
    935             i++;
    936         } else if ((mode&PROC_QUOTES) != 0) {
    937             while (buffer[i] != '"' && i < endIndex) {
    938                 i++;
    939             }
    940             end = i;
    941             i++;
    942         }
    943         while (i < endIndex && buffer[i] != term) {
    944             i++;
    945         }
    946         if (end < 0) {
    947             end = i;
    948         }
    949 
    950         if (i < endIndex) {
    951             i++;
    952             if ((mode&PROC_COMBINE) != 0) {
    953                 while (i < endIndex && buffer[i] == term) {
    954                     i++;
    955                 }
    956             }
    957         }
    958 
    959         //ALOGI("Field %" PRId32 ": %" PRId32 "-%" PRId32 " dest=%" PRId32 " mode=0x%" PRIx32 "\n", i, start, end, di, mode);
    960 
    961         if ((mode&(PROC_OUT_FLOAT|PROC_OUT_LONG|PROC_OUT_STRING)) != 0) {
    962             char c = buffer[end];
    963             buffer[end] = 0;
    964             if ((mode&PROC_OUT_FLOAT) != 0 && di < NR) {
    965                 char* end;
    966                 floatsData[di] = strtof(buffer+start, &end);
    967             }
    968             if ((mode&PROC_OUT_LONG) != 0 && di < NL) {
    969                 if ((mode&PROC_CHAR) != 0) {
    970                     // Caller wants single first character returned as one long.
    971                     longsData[di] = buffer[start];
    972                 } else {
    973                     char* end;
    974                     longsData[di] = strtoll(buffer+start, &end, 10);
    975                 }
    976             }
    977             if ((mode&PROC_OUT_STRING) != 0 && di < NS) {
    978                 jstring str = env->NewStringUTF(buffer+start);
    979                 env->SetObjectArrayElement(outStrings, di, str);
    980             }
    981             buffer[end] = c;
    982             di++;
    983         }
    984     }
    985 
    986     env->ReleaseIntArrayElements(format, formatData, 0);
    987     if (longsData != NULL) {
    988         env->ReleaseLongArrayElements(outLongs, longsData, 0);
    989     }
    990     if (floatsData != NULL) {
    991         env->ReleaseFloatArrayElements(outFloats, floatsData, 0);
    992     }
    993 
    994     return res;
    995 }
    996 
    997 jboolean android_os_Process_parseProcLine(JNIEnv* env, jobject clazz,
    998         jbyteArray buffer, jint startIndex, jint endIndex, jintArray format,
    999         jobjectArray outStrings, jlongArray outLongs, jfloatArray outFloats)
   1000 {
   1001         jbyte* bufferArray = env->GetByteArrayElements(buffer, NULL);
   1002 
   1003         jboolean result = android_os_Process_parseProcLineArray(env, clazz,
   1004                 (char*) bufferArray, startIndex, endIndex, format, outStrings,
   1005                 outLongs, outFloats);
   1006 
   1007         env->ReleaseByteArrayElements(buffer, bufferArray, 0);
   1008 
   1009         return result;
   1010 }
   1011 
   1012 jboolean android_os_Process_readProcFile(JNIEnv* env, jobject clazz,
   1013         jstring file, jintArray format, jobjectArray outStrings,
   1014         jlongArray outLongs, jfloatArray outFloats)
   1015 {
   1016     if (file == NULL || format == NULL) {
   1017         jniThrowNullPointerException(env, NULL);
   1018         return JNI_FALSE;
   1019     }
   1020 
   1021     const char* file8 = env->GetStringUTFChars(file, NULL);
   1022     if (file8 == NULL) {
   1023         jniThrowException(env, "java/lang/OutOfMemoryError", NULL);
   1024         return JNI_FALSE;
   1025     }
   1026     int fd = open(file8, O_RDONLY | O_CLOEXEC);
   1027 
   1028     if (fd < 0) {
   1029         if (kDebugProc) {
   1030             ALOGW("Unable to open process file: %s\n", file8);
   1031         }
   1032         env->ReleaseStringUTFChars(file, file8);
   1033         return JNI_FALSE;
   1034     }
   1035     env->ReleaseStringUTFChars(file, file8);
   1036 
   1037     char buffer[256];
   1038     const int len = read(fd, buffer, sizeof(buffer)-1);
   1039     close(fd);
   1040 
   1041     if (len < 0) {
   1042         if (kDebugProc) {
   1043             ALOGW("Unable to open process file: %s fd=%d\n", file8, fd);
   1044         }
   1045         return JNI_FALSE;
   1046     }
   1047     buffer[len] = 0;
   1048 
   1049     return android_os_Process_parseProcLineArray(env, clazz, buffer, 0, len,
   1050             format, outStrings, outLongs, outFloats);
   1051 
   1052 }
   1053 
   1054 void android_os_Process_setApplicationObject(JNIEnv* env, jobject clazz,
   1055                                              jobject binderObject)
   1056 {
   1057     if (binderObject == NULL) {
   1058         jniThrowNullPointerException(env, NULL);
   1059         return;
   1060     }
   1061 
   1062     sp<IBinder> binder = ibinderForJavaObject(env, binderObject);
   1063 }
   1064 
   1065 void android_os_Process_sendSignal(JNIEnv* env, jobject clazz, jint pid, jint sig)
   1066 {
   1067     if (pid > 0) {
   1068         ALOGI("Sending signal. PID: %" PRId32 " SIG: %" PRId32, pid, sig);
   1069         kill(pid, sig);
   1070     }
   1071 }
   1072 
   1073 void android_os_Process_sendSignalQuiet(JNIEnv* env, jobject clazz, jint pid, jint sig)
   1074 {
   1075     if (pid > 0) {
   1076         kill(pid, sig);
   1077     }
   1078 }
   1079 
   1080 static jlong android_os_Process_getElapsedCpuTime(JNIEnv* env, jobject clazz)
   1081 {
   1082     struct timespec ts;
   1083 
   1084     int res = clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &ts);
   1085 
   1086     if (res != 0) {
   1087         return (jlong) 0;
   1088     }
   1089 
   1090     nsecs_t when = seconds_to_nanoseconds(ts.tv_sec) + ts.tv_nsec;
   1091     return (jlong) nanoseconds_to_milliseconds(when);
   1092 }
   1093 
   1094 static jlong android_os_Process_getPss(JNIEnv* env, jobject clazz, jint pid)
   1095 {
   1096     UniqueFile file = OpenSmapsOrRollup(pid);
   1097     if (file == nullptr) {
   1098         return (jlong) -1;
   1099     }
   1100 
   1101     // Tally up all of the Pss from the various maps
   1102     char line[256];
   1103     jlong pss = 0;
   1104     while (fgets(line, sizeof(line), file.get())) {
   1105         jlong v;
   1106         if (sscanf(line, "Pss: %" SCNd64 " kB", &v) == 1) {
   1107             pss += v;
   1108         }
   1109     }
   1110 
   1111     // Return the Pss value in bytes, not kilobytes
   1112     return pss * 1024;
   1113 }
   1114 
   1115 jintArray android_os_Process_getPidsForCommands(JNIEnv* env, jobject clazz,
   1116         jobjectArray commandNames)
   1117 {
   1118     if (commandNames == NULL) {
   1119         jniThrowNullPointerException(env, NULL);
   1120         return NULL;
   1121     }
   1122 
   1123     Vector<String8> commands;
   1124 
   1125     jsize count = env->GetArrayLength(commandNames);
   1126 
   1127     for (int i=0; i<count; i++) {
   1128         jobject obj = env->GetObjectArrayElement(commandNames, i);
   1129         if (obj != NULL) {
   1130             const char* str8 = env->GetStringUTFChars((jstring)obj, NULL);
   1131             if (str8 == NULL) {
   1132                 jniThrowNullPointerException(env, "Element in commandNames");
   1133                 return NULL;
   1134             }
   1135             commands.add(String8(str8));
   1136             env->ReleaseStringUTFChars((jstring)obj, str8);
   1137         } else {
   1138             jniThrowNullPointerException(env, "Element in commandNames");
   1139             return NULL;
   1140         }
   1141     }
   1142 
   1143     Vector<jint> pids;
   1144 
   1145     DIR *proc = opendir("/proc");
   1146     if (proc == NULL) {
   1147         fprintf(stderr, "/proc: %s\n", strerror(errno));
   1148         return NULL;
   1149     }
   1150 
   1151     struct dirent *d;
   1152     while ((d = readdir(proc))) {
   1153         int pid = atoi(d->d_name);
   1154         if (pid <= 0) continue;
   1155 
   1156         char path[PATH_MAX];
   1157         char data[PATH_MAX];
   1158         snprintf(path, sizeof(path), "/proc/%d/cmdline", pid);
   1159 
   1160         int fd = open(path, O_RDONLY | O_CLOEXEC);
   1161         if (fd < 0) {
   1162             continue;
   1163         }
   1164         const int len = read(fd, data, sizeof(data)-1);
   1165         close(fd);
   1166 
   1167         if (len < 0) {
   1168             continue;
   1169         }
   1170         data[len] = 0;
   1171 
   1172         for (int i=0; i<len; i++) {
   1173             if (data[i] == ' ') {
   1174                 data[i] = 0;
   1175                 break;
   1176             }
   1177         }
   1178 
   1179         for (size_t i=0; i<commands.size(); i++) {
   1180             if (commands[i] == data) {
   1181                 pids.add(pid);
   1182                 break;
   1183             }
   1184         }
   1185     }
   1186 
   1187     closedir(proc);
   1188 
   1189     jintArray pidArray = env->NewIntArray(pids.size());
   1190     if (pidArray == NULL) {
   1191         jniThrowException(env, "java/lang/OutOfMemoryError", NULL);
   1192         return NULL;
   1193     }
   1194 
   1195     if (pids.size() > 0) {
   1196         env->SetIntArrayRegion(pidArray, 0, pids.size(), pids.array());
   1197     }
   1198 
   1199     return pidArray;
   1200 }
   1201 
   1202 jint android_os_Process_killProcessGroup(JNIEnv* env, jobject clazz, jint uid, jint pid)
   1203 {
   1204     return killProcessGroup(uid, pid, SIGKILL);
   1205 }
   1206 
   1207 void android_os_Process_removeAllProcessGroups(JNIEnv* env, jobject clazz)
   1208 {
   1209     return removeAllProcessGroups();
   1210 }
   1211 
   1212 static const JNINativeMethod methods[] = {
   1213     {"getUidForName",       "(Ljava/lang/String;)I", (void*)android_os_Process_getUidForName},
   1214     {"getGidForName",       "(Ljava/lang/String;)I", (void*)android_os_Process_getGidForName},
   1215     {"setThreadPriority",   "(II)V", (void*)android_os_Process_setThreadPriority},
   1216     {"setThreadScheduler",  "(III)V", (void*)android_os_Process_setThreadScheduler},
   1217     {"setCanSelfBackground", "(Z)V", (void*)android_os_Process_setCanSelfBackground},
   1218     {"setThreadPriority",   "(I)V", (void*)android_os_Process_setCallingThreadPriority},
   1219     {"getThreadPriority",   "(I)I", (void*)android_os_Process_getThreadPriority},
   1220     {"getThreadScheduler",   "(I)I", (void*)android_os_Process_getThreadScheduler},
   1221     {"setThreadGroup",      "(II)V", (void*)android_os_Process_setThreadGroup},
   1222     {"setThreadGroupAndCpuset", "(II)V", (void*)android_os_Process_setThreadGroupAndCpuset},
   1223     {"setProcessGroup",     "(II)V", (void*)android_os_Process_setProcessGroup},
   1224     {"getProcessGroup",     "(I)I", (void*)android_os_Process_getProcessGroup},
   1225     {"getExclusiveCores",   "()[I", (void*)android_os_Process_getExclusiveCores},
   1226     {"setSwappiness",   "(IZ)Z", (void*)android_os_Process_setSwappiness},
   1227     {"setArgV0",    "(Ljava/lang/String;)V", (void*)android_os_Process_setArgV0},
   1228     {"setUid", "(I)I", (void*)android_os_Process_setUid},
   1229     {"setGid", "(I)I", (void*)android_os_Process_setGid},
   1230     {"sendSignal", "(II)V", (void*)android_os_Process_sendSignal},
   1231     {"sendSignalQuiet", "(II)V", (void*)android_os_Process_sendSignalQuiet},
   1232     {"getFreeMemory", "()J", (void*)android_os_Process_getFreeMemory},
   1233     {"getTotalMemory", "()J", (void*)android_os_Process_getTotalMemory},
   1234     {"readProcLines", "(Ljava/lang/String;[Ljava/lang/String;[J)V", (void*)android_os_Process_readProcLines},
   1235     {"getPids", "(Ljava/lang/String;[I)[I", (void*)android_os_Process_getPids},
   1236     {"readProcFile", "(Ljava/lang/String;[I[Ljava/lang/String;[J[F)Z", (void*)android_os_Process_readProcFile},
   1237     {"parseProcLine", "([BII[I[Ljava/lang/String;[J[F)Z", (void*)android_os_Process_parseProcLine},
   1238     {"getElapsedCpuTime", "()J", (void*)android_os_Process_getElapsedCpuTime},
   1239     {"getPss", "(I)J", (void*)android_os_Process_getPss},
   1240     {"getPidsForCommands", "([Ljava/lang/String;)[I", (void*)android_os_Process_getPidsForCommands},
   1241     //{"setApplicationObject", "(Landroid/os/IBinder;)V", (void*)android_os_Process_setApplicationObject},
   1242     {"killProcessGroup", "(II)I", (void*)android_os_Process_killProcessGroup},
   1243     {"removeAllProcessGroups", "()V", (void*)android_os_Process_removeAllProcessGroups},
   1244 };
   1245 
   1246 int register_android_os_Process(JNIEnv* env)
   1247 {
   1248     return RegisterMethodsOrDie(env, "android/os/Process", methods, NELEM(methods));
   1249 }
   1250