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/*
* Copyright (C) 2017 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#define DEBUG false
#include "Log.h"
#include "incidentd_util.h"
#include <sys/prctl.h>
#include <wait.h>
#include "section_list.h"
const Privacy* get_privacy_of_section(int id) {
int l = 0;
int r = PRIVACY_POLICY_COUNT - 1;
while (l <= r) {
int mid = (l + r) >> 1;
const Privacy* p = PRIVACY_POLICY_LIST[mid];
if (p->field_id < (uint32_t)id) {
l = mid + 1;
} else if (p->field_id > (uint32_t)id) {
r = mid - 1;
} else {
return p;
}
}
return NULL;
}
// ================================================================================
Fpipe::Fpipe() : mRead(), mWrite() {}
Fpipe::~Fpipe() { close(); }
bool Fpipe::close() {
mRead.reset();
mWrite.reset();
return true;
}
bool Fpipe::init() { return Pipe(&mRead, &mWrite); }
unique_fd& Fpipe::readFd() { return mRead; }
unique_fd& Fpipe::writeFd() { return mWrite; }
pid_t fork_execute_cmd(char* const argv[], Fpipe* input, Fpipe* output) {
// fork used in multithreaded environment, avoid adding unnecessary code in child process
pid_t pid = fork();
if (pid == 0) {
VLOG("[In child]cmd %s", argv[0]);
if (input != NULL && (TEMP_FAILURE_RETRY(dup2(input->readFd().get(), STDIN_FILENO)) < 0 ||
!input->close())) {
ALOGW("Failed to dup2 stdin.");
_exit(EXIT_FAILURE);
}
if (TEMP_FAILURE_RETRY(dup2(output->writeFd().get(), STDOUT_FILENO)) < 0 ||
!output->close()) {
ALOGW("Failed to dup2 stdout.");
_exit(EXIT_FAILURE);
}
/* make sure the child dies when incidentd dies */
prctl(PR_SET_PDEATHSIG, SIGKILL);
execvp(argv[0], argv);
_exit(errno); // always exits with failure if any
}
// close the fds used in child process.
if (input != NULL) input->readFd().reset();
output->writeFd().reset();
return pid;
}
// ================================================================================
const char** varargs(const char* first, va_list rest) {
va_list copied_rest;
int numOfArgs = 1; // first is already count.
va_copy(copied_rest, rest);
while (va_arg(copied_rest, const char*) != NULL) {
numOfArgs++;
}
va_end(copied_rest);
// allocate extra 1 for NULL terminator
const char** ret = (const char**)malloc(sizeof(const char*) * (numOfArgs + 1));
ret[0] = first;
for (int i = 1; i < numOfArgs; i++) {
const char* arg = va_arg(rest, const char*);
ret[i] = arg;
}
ret[numOfArgs] = NULL;
return ret;
}
// ================================================================================
const uint64_t NANOS_PER_SEC = 1000000000;
uint64_t Nanotime() {
timespec ts;
clock_gettime(CLOCK_MONOTONIC, &ts);
return static_cast<uint64_t>(ts.tv_sec * NANOS_PER_SEC + ts.tv_nsec);
}
// ================================================================================
const int WAIT_MAX = 5;
const struct timespec WAIT_INTERVAL_NS = {0, 200 * 1000 * 1000};
static status_t statusCode(int status) {
if (WIFSIGNALED(status)) {
VLOG("return by signal: %s", strerror(WTERMSIG(status)));
return -WTERMSIG(status);
} else if (WIFEXITED(status) && WEXITSTATUS(status) > 0) {
VLOG("return by exit: %s", strerror(WEXITSTATUS(status)));
return -WEXITSTATUS(status);
}
return NO_ERROR;
}
status_t kill_child(pid_t pid) {
int status;
VLOG("try to kill child process %d", pid);
kill(pid, SIGKILL);
if (waitpid(pid, &status, 0) == -1) return -1;
return statusCode(status);
}
status_t wait_child(pid_t pid) {
int status;
bool died = false;
// wait for child to report status up to 1 seconds
for (int loop = 0; !died && loop < WAIT_MAX; loop++) {
if (waitpid(pid, &status, WNOHANG) == pid) died = true;
// sleep for 0.2 second
nanosleep(&WAIT_INTERVAL_NS, NULL);
}
if (!died) return kill_child(pid);
return statusCode(status);
}
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