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// Copyright 2019 Roman Perepelitsa.
//
// This file is part of GitStatus.
//
// GitStatus is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// GitStatus is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with GitStatus. If not, see <https://www.gnu.org/licenses/>.
#include "request.h"
#include <fcntl.h>
#include <signal.h>
#include <sys/select.h>
#include <sys/types.h>
#include <unistd.h>
#include <algorithm>
#include <cstdlib>
#include <iostream>
#include "check.h"
#include "logging.h"
#include "print.h"
#include "serialization.h"
namespace gitstatus {
namespace {
Request ParseRequest(const std::string& s) {
Request res;
auto begin = s.begin(), end = s.end(), sep = std::find(begin, end, kFieldSep);
VERIFY(sep != end) << "Malformed request: " << s;
res.id.assign(begin, sep);
begin = sep + 1;
if (*begin == ':') {
res.from_dotgit = true;
++begin;
}
sep = std::find(begin, end, kFieldSep);
res.dir.assign(begin, sep);
if (sep == end) return res;
begin = sep + 1;
VERIFY(begin + 1 == end && (*begin == '0' || *begin == '1')) << "Malformed request: " << s;
res.diff = *begin == '0';
return res;
}
bool IsLockedFd(int fd) {
CHECK(fd >= 0);
struct flock flock = {};
flock.l_type = F_RDLCK;
flock.l_whence = SEEK_SET;
CHECK(fcntl(fd, F_GETLK, &flock) != -1) << Errno();
return flock.l_type != F_UNLCK;
}
} // namespace
std::ostream& operator<<(std::ostream& strm, const Request& req) {
strm << Print(req.id) << " for " << Print(req.dir);
if (req.from_dotgit) strm << " [from-dotgit]";
if (!req.diff) strm << " [no-diff]";
return strm;
}
RequestReader::RequestReader(int fd, int lock_fd, int parent_pid)
: fd_(fd), lock_fd_(lock_fd), parent_pid_(parent_pid) {
CHECK(fd != lock_fd);
}
bool RequestReader::ReadRequest(Request& req) {
auto eol = std::find(read_.begin(), read_.end(), kMsgSep);
if (eol != read_.end()) {
std::string msg(read_.begin(), eol);
read_.erase(read_.begin(), eol + 1);
req = ParseRequest(msg);
return true;
}
char buf[256];
while (true) {
fd_set fds;
FD_ZERO(&fds);
FD_SET(fd_, &fds);
struct timeval timeout = {.tv_sec = 1};
int n;
CHECK((n = select(fd_ + 1, &fds, NULL, NULL, &timeout)) >= 0) << Errno();
if (n == 0) {
if (lock_fd_ >= 0 && !IsLockedFd(lock_fd_)) {
LOG(INFO) << "Lock on fd " << lock_fd_ << " is gone. Exiting.";
std::exit(0);
}
if (parent_pid_ >= 0 && kill(parent_pid_, 0)) {
LOG(INFO) << "Unable to send signal 0 to " << parent_pid_ << ". Exiting.";
std::exit(0);
}
req = {};
return false;
}
CHECK((n = read(fd_, buf, sizeof(buf))) >= 0) << Errno();
if (n == 0) {
LOG(INFO) << "EOF. Exiting.";
std::exit(0);
}
read_.insert(read_.end(), buf, buf + n);
int eol = std::find(buf, buf + n, kMsgSep) - buf;
if (eol != n) {
std::string msg(read_.begin(), read_.end() - (n - eol));
read_.erase(read_.begin(), read_.begin() + msg.size() + 1);
req = ParseRequest(msg);
return true;
}
}
}
} // namespace gitstatus
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