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/**
* Copyright (c) 2007-2012, Timothy Stack
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* * Neither the name of Timothy Stack nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ''AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* @file piper_proc.cc
*/
#include "piper_proc.hh"
#include <errno.h>
#include <fcntl.h>
#include <poll.h>
#include <signal.h>
#include <stdio.h>
#include <string.h>
#include <sys/time.h>
#include <sys/wait.h>
#include <unistd.h>
#include "base/fs_util.hh"
#include "base/lnav_log.hh"
#include "config.h"
#include "line_buffer.hh"
using namespace std::chrono_literals;
static const char* STDIN_EOF_MSG = "---- END-OF-STDIN ----";
static ssize_t
write_timestamp(int fd, off_t woff)
{
char time_str[64];
struct timeval tv;
char ms_str[10];
gettimeofday(&tv, nullptr);
strftime(time_str, sizeof(time_str), "%FT%T", localtime(&tv.tv_sec));
snprintf(ms_str, sizeof(ms_str), ".%03d", (int) (tv.tv_usec / 1000));
strcat(time_str, ms_str);
strcat(time_str, " ");
return pwrite(fd, time_str, strlen(time_str), woff);
}
piper_proc::piper_proc(auto_fd pipefd, bool timestamp, auto_fd filefd)
: pp_fd(std::move(filefd)), pp_child(-1)
{
require(pipefd.get() >= 0);
require(this->pp_fd.get() >= 0);
log_perror(fcntl(this->pp_fd.get(), F_SETFD, FD_CLOEXEC));
this->pp_child = fork();
switch (this->pp_child) {
case -1:
throw error(errno);
case 0: {
line_buffer lb;
off_t woff = 0, last_woff = 0;
file_range last_range;
auto open_res = lnav::filesystem::open_file("/dev/null", O_RDWR);
if (open_res.isErr()) {
fprintf(stderr,
"unable to open /dev/null: %s\n",
open_res.unwrapErr().c_str());
exit(EXIT_FAILURE);
}
auto nullfd = open_res.unwrap();
if (pipefd != STDIN_FILENO) {
dup2(nullfd, STDIN_FILENO);
}
dup2(nullfd, STDOUT_FILENO);
for (int fd_to_close = 0; fd_to_close < 1024; fd_to_close++) {
int flags;
if (fd_to_close == this->pp_fd.get()) {
continue;
}
if ((flags = fcntl(fd_to_close, F_GETFD)) == -1) {
continue;
}
if (flags & FD_CLOEXEC) {
close(fd_to_close);
}
}
log_perror(fcntl(pipefd.get(), F_SETFL, O_NONBLOCK));
lb.set_fd(pipefd);
do {
static const auto TIMEOUT
= std::chrono::duration_cast<std::chrono::milliseconds>(1s)
.count();
struct pollfd pfd = {lb.get_fd(), POLLIN, 0};
auto poll_rc = poll(&pfd, 1, TIMEOUT);
if (poll_rc == 0) {
// update the timestamp to keep the file alive from any
// cleanup processes
log_perror(futimes(this->pp_fd.get(), nullptr));
continue;
}
while (true) {
auto load_result = lb.load_next_line(last_range);
if (load_result.isErr()) {
break;
}
auto li = load_result.unwrap();
if (li.li_partial && !lb.is_pipe_closed()) {
break;
}
if (li.li_file_range.empty()) {
break;
}
auto read_result = lb.read_range(li.li_file_range);
if (read_result.isErr()) {
break;
}
auto sbr = read_result.unwrap();
ssize_t wrc;
last_woff = woff;
if (timestamp) {
wrc = write_timestamp(this->pp_fd, woff);
if (wrc == -1) {
perror("Unable to write to output file for stdin");
break;
}
woff += wrc;
}
/* Need to do pwrite here since the fd is used by the main
* lnav process as well.
*/
wrc = pwrite(
this->pp_fd, sbr.get_data(), sbr.length(), woff);
if (wrc == -1) {
perror("Unable to write to output file for stdin");
break;
}
woff += wrc;
last_range = li.li_file_range;
if (li.li_partial
&& sbr.get_data()[sbr.length() - 1] != '\n'
&& (last_range.next_offset() != lb.get_file_size()))
{
woff = last_woff;
}
}
} while (lb.is_pipe() && !lb.is_pipe_closed());
if (timestamp) {
ssize_t wrc;
wrc = write_timestamp(this->pp_fd, woff);
if (wrc == -1) {
perror("Unable to write to output file for stdin");
break;
}
woff += wrc;
wrc = pwrite(
this->pp_fd, STDIN_EOF_MSG, strlen(STDIN_EOF_MSG), woff);
if (wrc == -1) {
perror("Unable to write to output file for stdin");
break;
}
}
}
_exit(0);
break;
default:
break;
}
}
bool
piper_proc::has_exited()
{
if (this->pp_child > 0) {
int rc, status;
rc = waitpid(this->pp_child, &status, WNOHANG);
if (rc == -1 || rc == 0) {
return false;
}
this->pp_child = -1;
}
return true;
}
piper_proc::~piper_proc()
{
if (this->pp_child > 0) {
int status;
kill(this->pp_child, SIGTERM);
while (waitpid(this->pp_child, &status, 0) < 0 && (errno == EINTR)) {
;
}
this->pp_child = -1;
}
}
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