blob: 3801028e2ddb285d6277da188413d86ceb622596 [file] [log] [blame]
// Copyright 2014 The Bazel Authors. All rights reserved.
//
// 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.
#include <errno.h> // errno, ENAMETOOLONG
#include <limits.h>
#include <linux/magic.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h> // strerror
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/statfs.h>
#include <sys/types.h>
#include <unistd.h>
#include "src/main/cpp/blaze_util.h"
#include "src/main/cpp/blaze_util_platform.h"
#include "src/main/cpp/util/errors.h"
#include "src/main/cpp/util/exit_code.h"
#include "src/main/cpp/util/file.h"
#include "src/main/cpp/util/logging.h"
#include "src/main/cpp/util/path.h"
#include "src/main/cpp/util/port.h"
#include "src/main/cpp/util/strings.h"
namespace blaze {
using blaze_util::GetLastErrorString;
using std::string;
using std::vector;
string GetOutputRoot() {
string base;
string home = GetHomeDir();
if (!home.empty()) {
base = home;
} else {
char buf[2048];
struct passwd pwbuf;
struct passwd *pw = NULL;
int uid = getuid();
int r = getpwuid_r(uid, &pwbuf, buf, 2048, &pw);
if (r != -1 && pw != NULL) {
base = pw->pw_dir;
}
}
if (!base.empty()) {
return blaze_util::JoinPath(base, ".cache/bazel");
}
return "/tmp";
}
void WarnFilesystemType(const string& output_base) {
struct statfs buf = {};
if (statfs(output_base.c_str(), &buf) < 0) {
BAZEL_LOG(WARNING) << "couldn't get file system type information for '"
<< output_base << "': " << strerror(errno);
return;
}
if (buf.f_type == NFS_SUPER_MAGIC) {
BAZEL_LOG(WARNING) << "Output base '" << output_base
<< "' is on NFS. This may lead to surprising failures "
"and undetermined behavior.";
}
}
string GetSelfPath() {
char buffer[PATH_MAX] = {};
ssize_t bytes = readlink("/proc/self/exe", buffer, sizeof(buffer));
if (bytes == sizeof(buffer)) {
// symlink contents truncated
bytes = -1;
errno = ENAMETOOLONG;
}
if (bytes == -1) {
BAZEL_DIE(blaze_exit_code::INTERNAL_ERROR)
<< "error reading /proc/self/exe: " << GetLastErrorString();
}
buffer[bytes] = '\0'; // readlink does not NUL-terminate
return string(buffer);
}
uint64_t GetMillisecondsMonotonic() {
struct timespec ts = {};
clock_gettime(CLOCK_MONOTONIC, &ts);
return ts.tv_sec * 1000LL + (ts.tv_nsec / 1000000LL);
}
void SetScheduling(bool batch_cpu_scheduling, int io_nice_level) {
if (batch_cpu_scheduling) {
sched_param param = {};
param.sched_priority = 0;
if (sched_setscheduler(0, SCHED_BATCH, &param)) {
BAZEL_DIE(blaze_exit_code::INTERNAL_ERROR)
<< "sched_setscheduler(SCHED_BATCH) failed: " << GetLastErrorString();
}
}
if (io_nice_level >= 0) {
if (blaze_util::sys_ioprio_set(
IOPRIO_WHO_PROCESS, getpid(),
IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, io_nice_level)) < 0) {
BAZEL_DIE(blaze_exit_code::INTERNAL_ERROR)
<< "ioprio_set() with class " << IOPRIO_CLASS_BE << " and level "
<< io_nice_level << " failed: " << GetLastErrorString();
}
}
}
string GetProcessCWD(int pid) {
char server_cwd[PATH_MAX] = {};
if (readlink(
("/proc/" + ToString(pid) + "/cwd").c_str(),
server_cwd, sizeof(server_cwd)) < 0) {
return "";
}
return string(server_cwd);
}
bool IsSharedLibrary(const string &filename) {
return blaze_util::ends_with(filename, ".so");
}
static string Which(const string &executable) {
string path(GetEnv("PATH"));
if (path.empty()) {
return "";
}
vector<string> pieces = blaze_util::Split(path, ':');
for (auto piece : pieces) {
if (piece.empty()) {
piece = ".";
}
struct stat file_stat;
string candidate = blaze_util::JoinPath(piece, executable);
if (access(candidate.c_str(), X_OK) == 0 &&
stat(candidate.c_str(), &file_stat) == 0 &&
S_ISREG(file_stat.st_mode)) {
return candidate;
}
}
return "";
}
string GetSystemJavabase() {
// if JAVA_HOME is defined, then use it as default.
string javahome = GetEnv("JAVA_HOME");
if (!javahome.empty()) {
string javac = blaze_util::JoinPath(javahome, "bin/javac");
if (access(javac.c_str(), X_OK) == 0) {
return javahome;
}
BAZEL_LOG(WARNING)
<< "Ignoring JAVA_HOME, because it must point to a JDK, not a JRE.";
}
// which javac
string javac_dir = Which("javac");
if (javac_dir.empty()) {
return "";
}
// Resolve all symlinks.
char resolved_path[PATH_MAX];
if (realpath(javac_dir.c_str(), resolved_path) == NULL) {
return "";
}
javac_dir = resolved_path;
// dirname dirname
return blaze_util::Dirname(blaze_util::Dirname(javac_dir));
}
// Called from a signal handler!
static bool GetStartTime(const string& pid, string* start_time) {
string statfile = "/proc/" + pid + "/stat";
string statline;
if (!blaze_util::ReadFile(statfile, &statline)) {
return false;
}
vector<string> stat_entries = blaze_util::Split(statline, ' ');
if (stat_entries.size() < 22) {
BAZEL_DIE(blaze_exit_code::LOCAL_ENVIRONMENTAL_ERROR)
<< "Format of stat file at " << statfile
<< " is unknown: " << GetLastErrorString();
}
// Start time since startup in jiffies. This combined with the PID should be
// unique.
*start_time = stat_entries[21];
return true;
}
void WriteSystemSpecificProcessIdentifier(
const string& server_dir, pid_t server_pid) {
string pid_string = ToString(server_pid);
string start_time;
if (!GetStartTime(pid_string, &start_time)) {
BAZEL_DIE(blaze_exit_code::LOCAL_ENVIRONMENTAL_ERROR)
<< "Cannot get start time of process " << pid_string << ": "
<< GetLastErrorString();
}
string start_time_file = blaze_util::JoinPath(server_dir, "server.starttime");
if (!blaze_util::WriteFile(start_time, start_time_file)) {
BAZEL_DIE(blaze_exit_code::LOCAL_ENVIRONMENTAL_ERROR)
<< "Cannot write start time in server dir " << server_dir << ": "
<< GetLastErrorString();
}
}
// On Linux we use a combination of PID and start time to identify the server
// process. That is supposed to be unique unless one can start more processes
// than there are PIDs available within a single jiffy.
bool VerifyServerProcess(int pid, const string& output_base) {
string start_time;
if (!GetStartTime(ToString(pid), &start_time)) {
// Cannot read PID file from /proc . Process died meantime, all is good. No
// stale server is present.
return false;
}
string recorded_start_time;
bool file_present = blaze_util::ReadFile(
blaze_util::JoinPath(output_base, "server/server.starttime"),
&recorded_start_time);
// If start time file got deleted, but PID file didn't, assume that this is an
// old Blaze process that doesn't know how to write start time files yet.
return !file_present || recorded_start_time == start_time;
}
// Not supported.
void ExcludePathFromBackup(const string &path) {
}
int32_t GetExplicitSystemLimit(const int resource) {
return -1;
}
} // namespace blaze