From fd25c666d57fb9a7c0da58620a7cc768c7aa743e Mon Sep 17 00:00:00 2001 From: "C. McEnroe" Date: Thu, 25 Feb 2021 15:42:24 -0500 Subject: Add catsit-watch utility --- .gitignore | 1 + Makefile | 48 +++++++++++++++++++++--------- catsit-watch.1 | 52 ++++++++++++++++++++++++++++++++ catsit-watch.c | 94 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ catsit.conf.5 | 1 + 5 files changed, 182 insertions(+), 14 deletions(-) create mode 100644 catsit-watch.1 create mode 100644 catsit-watch.c diff --git a/.gitignore b/.gitignore index 3b0a7f4..d09ccdd 100644 --- a/.gitignore +++ b/.gitignore @@ -1,5 +1,6 @@ *.o catsit +catsit-watch catsit.conf catsitd config.mk diff --git a/Makefile b/Makefile index 392aacc..573c1f3 100644 --- a/Makefile +++ b/Makefile @@ -16,16 +16,18 @@ RC_SCRIPT = ${UNAME}/catsitd -include config.mk -BINS = catsit catsitd -MAN8 = ${BINS:=.8} +BINS = catsit-watch +SBINS = catsit catsitd +MAN1 = ${BINS:=.1} MAN5 = catsit.conf.5 +MAN8 = ${SBINS:=.8} OBJS += daemon.o OBJS += service.o dev: tags all -all: ${BINS} +all: ${BINS} ${SBINS} catsitd: ${OBJS} ${CC} ${LDFLAGS} ${OBJS} ${LDLIBS} -o $@ @@ -38,22 +40,40 @@ ${OBJS}: daemon.h sed -e 's|%%PREFIX%%|${PREFIX}|g' -e 's|%%RUNDIR%%|${RUNDIR}|g' $< > $@ chmod a+x $@ -tags: *.c *.h - ctags -w *.c *.h +tags: *.[ch] + ctags -w *.[ch] clean: - rm -f ${BINS} ${OBJS} ${RC_SCRIPT} tags - -install: ${BINS} ${RC_SCRIPT} ${MAN5} ${MAN8} - install -d ${DESTDIR}${PREFIX}/sbin ${DESTDIR}${ETCDIR}/rc.d - install -d ${DESTDIR}${MANDIR}/man5 ${DESTDIR}${MANDIR}/man8 - install ${BINS} ${DESTDIR}${PREFIX}/sbin + rm -f ${BINS} ${SBINS} ${OBJS} ${RC_SCRIPT} tags + +install: ${BINS} ${SBINS} ${RC_SCRIPT} ${MAN1} ${MAN5} ${MAN8} + install -d ${DESTDIR}${PREFIX}/bin + install -d ${DESTDIR}${PREFIX}/sbin + install -d ${DESTDIR}${MANDIR}/man1 + install -d ${DESTDIR}${MANDIR}/man5 + install -d ${DESTDIR}${MANDIR}/man8 + install -d ${DESTDIR}${ETCDIR}/rc.d + install ${BINS} ${DESTDIR}${PREFIX}/bin + install ${SBINS} ${DESTDIR}${PREFIX}/sbin install ${RC_SCRIPT} ${DESTDIR}${ETCDIR}/rc.d + install -m 644 ${MAN1} ${DESTDIR}${MANDIR}/man1 install -m 644 ${MAN5} ${DESTDIR}${MANDIR}/man5 install -m 644 ${MAN8} ${DESTDIR}${MANDIR}/man8 uninstall: - rm -f ${BINS:%=${DESTDIR}${PREFIX}/sbin/%} - rm -f ${MAN5:%=${DESTDIR}${MANDIR}/man5/%} - rm -f ${MAN8:%=${DESTDIR}${MANDIR}/man8/%} +.for BIN in ${BINS} + rm -f ${DESTDIR}${PREFIX}/bin/${BIN} +.endfor +.for SBIN in ${SBINS} + rm -f ${DESTDIR}${PREFIX}/sbin/${SBIN} +.endfor rm -f ${DESTDIR}${ETCDIR}/rc.d/${RC_SCRIPT:T} +.for MAN in ${MAN1} + rm -f ${DESTDIR}${MANDIR}/man1/${MAN} +.endfor +.for MAN in ${MAN5} + rm -f ${DESTDIR}${MANDIR}/man5/${MAN} +.endfor +.for MAN in ${MAN8} + rm -f ${DESTDIR}${MANDIR}/man8/${MAN} +.endfor diff --git a/catsit-watch.1 b/catsit-watch.1 new file mode 100644 index 0000000..b45f704 --- /dev/null +++ b/catsit-watch.1 @@ -0,0 +1,52 @@ +.Dd February 25, 2021 +.Dt CATSIT-WATCH 1 +.Os +. +.Sh NAME +.Nm catsit-watch +.Nd run command when files are modified +. +.Sh SYNOPSIS +.Nm +.Op Fl i +.Op Fl f Ar file +.Ar command ... +. +.Sh DESCRIPTION +The +.Nm +utility runs a command +each time any of a set of files +are modified. +If any watched files are removed +or if the command exits non-zero, +.Nm +exits. +. +.Pp +The arguments are as follows: +.Bl -tag -width Ds +.It Fl f Ar file +Add +.Ar file +to the set of watched files. +.It Fl i +Run the command once initially, +before watching files. +.El +. +.Sh EXIT STATUS +If any watched files are removed, +.Nm +exits with +.Dv EX_TEMPFAIL +(75). +If the command exits non-zero, +.Nm +exits with the same status. +. +.Sh SEE ALSO +.Xr catsitd 8 +. +.Sh AUTHORS +.An June Bug Aq Mt june@causal.agency diff --git a/catsit-watch.c b/catsit-watch.c new file mode 100644 index 0000000..4d0840c --- /dev/null +++ b/catsit-watch.c @@ -0,0 +1,94 @@ +/* Copyright (C) 2021 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 + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * This program 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 Affero General Public License for more details. + * + * You should have received a copy of the GNU Affero General Public License + * along with this program. If not, see . + */ + +#include + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +static void watch(int kq, char *path) { + int fd = open(path, O_RDONLY | O_CLOEXEC); + if (fd < 0) err(EX_NOINPUT, "%s", path); + + struct kevent event; + EV_SET( + &event, fd, EVFILT_VNODE, EV_ADD | EV_CLEAR, + NOTE_WRITE | NOTE_DELETE, 0, path + ); + int nevents = kevent(kq, &event, 1, NULL, 0, NULL); + if (nevents < 0) err(EX_OSERR, "kevent"); +} + +static void run(char *argv[]) { + pid_t pid = fork(); + if (pid < 0) err(EX_OSERR, "fork"); + if (!pid) { + execvp(argv[0], argv); + err(126, "%s", argv[0]); + } + + int status; + pid = wait(&status); + if (pid < 0) err(EX_OSERR, "wait"); + if (WIFEXITED(status)) { + status = WEXITSTATUS(status); + if (status) exit(status); + } else { + exit(status); + } +} + +int main(int argc, char *argv[]) { + int kq = kqueue(); + if (kq < 0) err(EX_OSERR, "kqueue"); + fcntl(kq, F_SETFD, FD_CLOEXEC); + + int init = 0; + for (int opt; 0 < (opt = getopt(argc, argv, "f:i"));) { + switch (opt) { + break; case 'f': watch(kq, optarg); + break; case 'i': init = 1; + break; default: return EX_USAGE; + } + } + argc -= optind; + argv += optind; + if (!argc) errx(EX_USAGE, "command required"); + +#ifdef __OpenBSD__ + int error = pledge("stdio proc exec", NULL); + if (error) err(EX_OSERR, "pledge"); +#endif + + if (init) run(argv); + for (;;) { + struct kevent event; + int nevents = kevent(kq, NULL, 0, &event, 1, NULL); + if (nevents < 0) err(EX_OSERR, "kevent"); + + if (event.fflags & NOTE_DELETE) { + errx(EX_TEMPFAIL, "%s: file removed", (char *)event.udata); + } + run(argv); + } +} diff --git a/catsit.conf.5 b/catsit.conf.5 index c18f683..7469e74 100644 --- a/catsit.conf.5 +++ b/catsit.conf.5 @@ -80,6 +80,7 @@ pounce/tilde pounce ${0#*/}.conf .Ed . .Sh SEE ALSO +.Xr catsit-watch 1 , .Xr catsitd 8 . .Sh AUTHORS -- cgit 1.4.1