From 022d24b9009f4b47c2f4229c57dad1e5c2fe1393 Mon Sep 17 00:00:00 2001 From: Curtis McEnroe Date: Mon, 12 Aug 2019 14:23:54 -0400 Subject: Make dtch one command, add sinking --- bin/dtch.c | 221 +++++++++++++++++++++++++++++++------------------------------ 1 file changed, 112 insertions(+), 109 deletions(-) (limited to 'bin/dtch.c') diff --git a/bin/dtch.c b/bin/dtch.c index 059d1a48..2aea53ae 100644 --- a/bin/dtch.c +++ b/bin/dtch.c @@ -1,4 +1,4 @@ -/* Copyright (C) 2017, 2018 C. McEnroe +/* Copyright (C) 2017-2019 C. McEnroe * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU Affero General Public License as published by @@ -19,8 +19,10 @@ #include #include #include +#include #include #include +#include #include #include #include @@ -38,25 +40,17 @@ #include #endif -typedef unsigned char byte; +static char _; +static struct iovec iov = { .iov_base = &_, .iov_len = 1 }; -static struct sockaddr_un sockAddr(const char *home, const char *name) { - struct sockaddr_un addr = { .sun_family = AF_UNIX }; - snprintf(addr.sun_path, sizeof(addr.sun_path), "%s/.dtch/%s", home, name); - return addr; -} - -static byte z; -static struct iovec iov = { .iov_base = &z, .iov_len = 1 }; - -static ssize_t sendFD(int sock, int fd) { - size_t size = CMSG_SPACE(sizeof(int)); - byte buf[size]; +static ssize_t sendfd(int sock, int fd) { + size_t len = CMSG_SPACE(sizeof(int)); + char buf[len]; struct msghdr msg = { .msg_iov = &iov, .msg_iovlen = 1, .msg_control = buf, - .msg_controllen = size, + .msg_controllen = len, }; struct cmsghdr *cmsg = CMSG_FIRSTHDR(&msg); @@ -68,70 +62,33 @@ static ssize_t sendFD(int sock, int fd) { return sendmsg(sock, &msg, 0); } -static int recvFD(int sock) { - size_t size = CMSG_SPACE(sizeof(int)); - char buf[size]; +static int recvfd(int sock) { + size_t len = CMSG_SPACE(sizeof(int)); + char buf[len]; struct msghdr msg = { .msg_iov = &iov, .msg_iovlen = 1, .msg_control = buf, - .msg_controllen = size, + .msg_controllen = len, }; - - ssize_t n = recvmsg(sock, &msg, 0); - if (n < 0) return -1; + if (0 > recvmsg(sock, &msg, 0)) return -1; struct cmsghdr *cmsg = CMSG_FIRSTHDR(&msg); if (!cmsg || cmsg->cmsg_type != SCM_RIGHTS) { errno = ENOMSG; return -1; } - return *(int *)CMSG_DATA(cmsg); } -static struct sockaddr_un addr; +static struct sockaddr_un addr = { .sun_family = AF_UNIX }; -static void sigExit(int sig) { +static void handler(int sig) { unlink(addr.sun_path); - _exit(128 + sig); + _exit(-sig); } -static int dtch(int argc, char *argv[]) { - int error; - - const char *name = "dtch"; - if (argc > 1) { - name = argv[1]; - argv++; - argc--; - } - if (argc > 1) { - argv++; - } else { - argv[0] = getenv("SHELL"); - if (!argv[0]) argv[0] = "/bin/sh"; - } - - const char *home = getenv("HOME"); - if (!home) errx(EX_CONFIG, "HOME unset"); - - int fd = open(home, 0); - if (fd < 0) err(EX_CANTCREAT, "%s", home); - - error = mkdirat(fd, ".dtch", 0700); - if (error && errno != EEXIST) err(EX_CANTCREAT, "%s/.dtch", home); - - close(fd); - - int server = socket(PF_UNIX, SOCK_STREAM, 0); - if (server < 0) err(EX_OSERR, "socket"); - - addr = sockAddr(home, name); - error = bind(server, (struct sockaddr *)&addr, sizeof(addr)); - if (error) err(EX_CANTCREAT, "%s", addr.sun_path); - fcntl(server, F_SETFD, FD_CLOEXEC); - +static void detach(int server, bool sink, char *argv[]) { int pty; pid_t pid = forkpty(&pty, NULL, NULL, NULL); if (pid < 0) err(EX_OSERR, "forkpty"); @@ -141,62 +98,64 @@ static int dtch(int argc, char *argv[]) { err(EX_NOINPUT, "%s", argv[0]); } - signal(SIGINT, sigExit); - signal(SIGTERM, sigExit); + signal(SIGINT, handler); + signal(SIGTERM, handler); - error = listen(server, 0); + int error = listen(server, 0); if (error) err(EX_OSERR, "listen"); - for (;;) { - int client = accept(server, NULL, NULL); - if (client < 0) err(EX_IOERR, "accept"); + struct pollfd fds[] = { + { .events = POLLIN, .fd = server }, + { .events = POLLIN, .fd = pty }, + }; + while (0 < poll(fds, (sink ? 2 : 1), -1)) { + if (fds[0].revents) { + int client = accept(server, NULL, NULL); + if (client < 0) err(EX_IOERR, "accept"); + + ssize_t len = sendfd(client, pty); + if (len < 0) warn("sendfd"); - ssize_t size = sendFD(client, pty); - if (size < 0) warn("sendmsg"); + len = recv(client, &_, sizeof(_), 0); + if (len < 0) warn("recv"); - size = recv(client, &z, sizeof(z), 0); - if (size < 0) warn("recv"); + close(client); + } - close(client); + if (fds[1].revents) { + char buf[4096]; + ssize_t len = read(pty, buf, sizeof(buf)); + if (len < 0) err(EX_IOERR, "read"); + } int status; pid_t dead = waitpid(pid, &status, WNOHANG); if (dead < 0) err(EX_OSERR, "waitpid"); if (dead) { unlink(addr.sun_path); - if (WIFEXITED(status)) return WEXITSTATUS(status); - else return 128 + WTERMSIG(status); + exit(WIFEXITED(status) ? WEXITSTATUS(status) : -WTERMSIG(status)); } } + err(EX_IOERR, "poll"); } static struct termios saveTerm; static void restoreTerm(void) { tcsetattr(STDIN_FILENO, TCSADRAIN, &saveTerm); - printf("\x1B\x63"); // rs1 + fprintf(stderr, "\33c"); // RIS + warnx("detached"); } -static void sigNop(int sig) { +static void nop(int sig) { (void)sig; } -static int atch(int argc, char *argv[]) { +static void attach(int client) { int error; - const char *home = getenv("HOME"); - if (!home) errx(EX_CONFIG, "HOME unset"); - - const char *name = (argc > 1) ? argv[1] : "dtch"; - - int client = socket(PF_UNIX, SOCK_STREAM, 0); - if (client < 0) err(EX_OSERR, "socket"); - - struct sockaddr_un addr = sockAddr(home, name); - error = connect(client, (struct sockaddr *)&addr, sizeof(addr)); - if (error) err(EX_NOINPUT, "%s", addr.sun_path); - - int pty = recvFD(client); - if (pty < 0) err(EX_IOERR, "recvmsg"); + int pty = recvfd(client); + if (pty < 0) err(EX_IOERR, "recvfd"); + warnx("attached"); struct winsize window; error = ioctl(STDIN_FILENO, TIOCGWINSZ, &window); @@ -218,16 +177,16 @@ static int atch(int argc, char *argv[]) { error = tcsetattr(STDIN_FILENO, TCSADRAIN, &raw); if (error) err(EX_IOERR, "tcsetattr"); - signal(SIGWINCH, sigNop); + signal(SIGWINCH, nop); - byte buf[4096]; - struct pollfd fds[2] = { + char buf[4096]; + struct pollfd fds[] = { { .events = POLLIN, .fd = STDIN_FILENO }, { .events = POLLIN, .fd = pty }, }; for (;;) { - int n = poll(fds, 2, -1); - if (n < 0) { + int nfds = poll(fds, 2, -1); + if (nfds < 0) { if (errno != EINTR) err(EX_IOERR, "poll"); error = ioctl(STDIN_FILENO, TIOCGWINSZ, &window); @@ -240,29 +199,73 @@ static int atch(int argc, char *argv[]) { } if (fds[0].revents) { - ssize_t size = read(STDIN_FILENO, buf, sizeof(buf)); - if (size < 0) err(EX_IOERR, "read(%d)", STDIN_FILENO); + ssize_t len = read(STDIN_FILENO, buf, sizeof(buf)); + if (len < 0) err(EX_IOERR, "read"); + if (!len) break; - if (size == 1 && buf[0] == CTRL('Q')) return EX_OK; + if (len == 1 && buf[0] == CTRL('Q')) break; - size = write(pty, buf, size); - if (size < 0) err(EX_IOERR, "write(%d)", pty); + len = write(pty, buf, len); + if (len < 0) err(EX_IOERR, "write"); } if (fds[1].revents) { - ssize_t size = read(pty, buf, sizeof(buf)); - if (size < 0) err(EX_IOERR, "read(%d)", pty); + ssize_t len = read(pty, buf, sizeof(buf)); + if (len < 0) err(EX_IOERR, "read"); + if (!len) break; - size = write(STDOUT_FILENO, buf, size); - if (size < 0) err(EX_IOERR, "write(%d)", STDOUT_FILENO); + len = write(STDOUT_FILENO, buf, len); + if (len < 0) err(EX_IOERR, "write"); } } } int main(int argc, char *argv[]) { - switch (argv[0][0]) { - case 'd': return dtch(argc, argv); - case 'a': return atch(argc, argv); - default: return EX_USAGE; + int error; + + bool atch = false; + bool sink = false; + + int opt; + while (0 < (opt = getopt(argc, argv, "as"))) { + switch (opt) { + break; case 'a': atch = true; + break; case 's': sink = true; + break; default: return EX_USAGE; + } + } + if (optind == argc) errx(EX_USAGE, "no session name"); + const char *name = argv[optind++]; + + if (optind == argc) { + argv[--optind] = getenv("SHELL"); + if (!argv[optind]) errx(EX_CONFIG, "SHELL unset"); + } + + const char *home = getenv("HOME"); + if (!home) errx(EX_CONFIG, "HOME unset"); + + int fd = open(home, 0); + if (fd < 0) err(EX_CANTCREAT, "%s", home); + + error = mkdirat(fd, ".dtch", 0700); + if (error && errno != EEXIST) err(EX_CANTCREAT, "%s/.dtch", home); + + close(fd); + + int sock = socket(PF_UNIX, SOCK_STREAM, 0); + if (sock < 0) err(EX_OSERR, "socket"); + fcntl(sock, F_SETFD, FD_CLOEXEC); + + snprintf(addr.sun_path, sizeof(addr.sun_path), "%s/.dtch/%s", home, name); + + if (atch) { + error = connect(sock, (struct sockaddr *)&addr, SUN_LEN(&addr)); + if (error) err(EX_NOINPUT, "%s", addr.sun_path); + attach(sock); + } else { + error = bind(sock, (struct sockaddr *)&addr, SUN_LEN(&addr)); + if (error) err(EX_CANTCREAT, "%s", addr.sun_path); + detach(sock, sink, &argv[optind]); } } -- cgit 1.4.1