diff options
| -rw-r--r-- | INSTALL | 2 | ||||
| -rw-r--r-- | doc/index.html | 6 | ||||
| -rw-r--r-- | doc/s6-devd.html | 4 | ||||
| -rw-r--r-- | doc/s6-uevent-listener.html | 99 | ||||
| -rw-r--r-- | doc/s6-uevent-spawner.html | 79 | ||||
| -rw-r--r-- | doc/upgrade.html | 11 | ||||
| -rw-r--r-- | package/deps.mak | 8 | ||||
| -rw-r--r-- | package/info | 2 | ||||
| -rw-r--r-- | package/modes | 30 | ||||
| -rw-r--r-- | package/targets.mak | 2 | ||||
| -rw-r--r-- | src/minutils/deps-exe/s6-uevent-listener | 1 | ||||
| -rw-r--r-- | src/minutils/deps-exe/s6-uevent-spawner | 1 | ||||
| -rw-r--r-- | src/minutils/s6-devd.c | 297 | ||||
| -rw-r--r-- | src/minutils/s6-uevent-listener.c | 233 | ||||
| -rw-r--r-- | src/minutils/s6-uevent-spawner.c | 234 |
15 files changed, 747 insertions, 262 deletions
@@ -6,7 +6,7 @@ Build Instructions - A Linux-based system with a standard C development environment - GNU make version 4.0 or later - - skalibs version 2.3.1.0 or later: http://skarnet.org/software/skalibs/ + - skalibs version 2.3.1.2 or later: http://skarnet.org/software/skalibs/ This software is Linux-specific. It will run on a Linux kernel, version 2.6.32 or later. diff --git a/doc/index.html b/doc/index.html index a899be8..a0fe7d7 100644 --- a/doc/index.html +++ b/doc/index.html @@ -32,7 +32,7 @@ <li> A Linux-based system with a standard C development environment </li> <li> GNU make, version 4.0 or later </li> <li> <a href="http://skarnet.org/software/skalibs/">skalibs</a> version -2.3.1.0 or later. It's a build-time requirement. It's also a run-time +2.3.1.2 or later. It's a build-time requirement. It's also a run-time requirement if you link against the shared version of the skalibs library. </li> </ul> @@ -47,7 +47,7 @@ library. </li> <h3> Download </h3> <ul> - <li> The current released version of s6-linux-utils is <a href="s6-linux-utils-2.0.1.0.tar.gz">2.0.1.0</a>. </li> + <li> The current released version of s6-linux-utils is <a href="s6-linux-utils-2.0.2.0.tar.gz">2.0.2.0</a>. </li> <li> Alternatively, you can checkout a copy of the s6-linux-utils git repository: <pre> git clone git://git.skarnet.org/s6-linux-utils </pre> </li> </ul> @@ -79,6 +79,8 @@ the previous versions of s6-linux-utils and the current one. </li> <ul> <li><a href="s6-chroot.html">The <tt>s6-chroot</tt> program</a></li> <li><a href="s6-devd.html">The <tt>s6-devd</tt> program</a></li> +<li><a href="s6-uevent-listener.html">The <tt>s6-uevent-listener</tt> program</a></li> +<li><a href="s6-uevent-spawner.html">The <tt>s6-uevent-spawner</tt> program</a></li> <li><a href="s6-freeramdisk.html">The <tt>s6-freeramdisk</tt> program</a></li> <li><a href="s6-halt.html">The <tt>s6-halt</tt> program</a></li> <li><a href="s6-hostname.html">The <tt>s6-hostname</tt> program</a></li> diff --git a/doc/s6-devd.html b/doc/s6-devd.html index 5ae6160..c67429a 100644 --- a/doc/s6-devd.html +++ b/doc/s6-devd.html @@ -36,7 +36,7 @@ hotplug events, as the <em>udev</em> program does. </li> the event variables added to the environment, just as if <em>prog...</em> had been registered in <tt>/proc/sys/kernel/hotplug</tt>. </li> <li> However, unlike the kernel, s6-devd spawns the <em>prog...</em> helpers -sequentially: it waits for an instance to finish before spawning another one. </li> +sequentially: it waits for an instance to finish before spawning another one. </li> <li> s6-devd is a long-lived program; it exits 0 when it receives a SIGTERM. If a helper program is alive at that time, s6-devd waits for it to die before exiting. </li> @@ -68,7 +68,7 @@ fork and logs to stderr.) </li> even if you are not using the <tt>-t</tt> option to s6-devd. Since helpers are spawned sequentially, slow helpers can make events queue up and fill the netlink kernel buffer. </li> - <li> If you are using <a href="http://busybox.net/">busybox</a> and want a + <li> If you are using <a href="http://busybox.net/">busybox</a> and want a minimal udev-style dynamic <tt>/dev</tt> handling, <tt>/sbin/mdev</tt> is a suitable <em>prog...</em> helper. </li> <li> The point of s6-devd is that it runs the helpers sequentially, so it solves diff --git a/doc/s6-uevent-listener.html b/doc/s6-uevent-listener.html new file mode 100644 index 0000000..9050e9f --- /dev/null +++ b/doc/s6-uevent-listener.html @@ -0,0 +1,99 @@ +<html> + <head> + <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> + <meta http-equiv="Content-Language" content="en" /> + <title>s6-linux-utils: the s6-uevent-listener program</title> + <meta name="Description" content="s6-linux-utils: the s6-uevent-listener program" /> + <meta name="Keywords" content="s6 linux administration root utilities devd mdev udev s6-uevent-listener uevent" /> + <!-- <link rel="stylesheet" type="text/css" href="http://skarnet.org/default.css" /> --> + </head> +<body> + +<p> +<a href="index.html">s6-linux-utils</a><br /> +<a href="http://skarnet.org/software/">Software</a><br /> +<a href="http://skarnet.org/">skarnet.org</a> +</p> + +<h1> The <tt>s6-uevent-listener</tt> program </h1> + +<p> +<tt>s6-uevent-listener</tt> spawns a long-lived helper program. +It then listens to the netlink interface for uevents (also called +"hotplug" or "udev" events), and passes those events to the +helper program's standard input, using a simple format. +</p> + +<h2> Interface </h2> + +<pre> + s6-uevent-listener [ -v <em>verbosity</em> ] [ -b kbufsz ] <em>prog...</em> +</pre> + +<ul> + <li> s6-uevent-listener spawns <em>prog...</em> with a pipe writing to +<em>prog</em>' stdin. </li> + <li> s6-uevent-listener binds to the netlink interface and listens for +hotplug events, as the <em>udev</em> program does. </li> + <li> It tranmits event information to <em>prog</em> via the pipe. </li> + <li> s6-uevent-listener, as well as <em>prog</em>, are long-lived programs. +When it receives a SIGTERM, s6-uevent-listener stops listening; it will +exit as soon as it has flushed its event queue to <em>prog</em>. </li> +</ul> + +<h2> Options </h2> + +<ul> + <li> <tt>-v</tt> <em>verbosity</em> : be more or less verbose. +Default verbosity is 1. 0 will only print fatal error messages, 3 will +print warnings every time the netlink interface sends something +unexpected. </li> + <li> <tt>-b</tt> <em>kbufsz</em> : try and reserve a kernel buffer of +<em>kbufsz</em> bytes for the netlink queue. Too large a buffer wastes kernel memory; +too small a buffer risks losing events. The default is 65536. </li> +</ul> + +<h2> Protocol </h2> + +<ul> + <li> <em>prog</em> should read a series of events on its stdin, and exit +on EOF. </li> + <li> An event is a series of null-terminated strings as they are sent by +the kernel to the netlink; s6-uevent-listener adds a final empty string +(i.e. an additional null character) to mark the end of the series. </li> + <li> The first string is a short description of the event; it normally +contains the string "@/". Other strings after the first are of the form +"VARIABLE=value", and describe the environment which a hotplug helper +for the event (registered in <tt>/proc/sys/kernel/hotplug</tt>) would be +spawned with. </li> + <li> Example (newlines added for clarity): <pre> +add@/class/input/input9/mouse2\0 +ACTION=add\0 +DEVPATH=/class/input/input9/mouse2\0 +SUBSYSTEM=input\0 +SEQNUM=106\0 +PHYSDEVPATH=/devices/pci0000:00/0000:00:1d.1/usb2/2Â2/2Â2:1.0 +PHYSDEVBUS=usb\0 +PHYSDEVDRIVER=usbhid\0 +MAJOR=13\0 +MINOR=34\0 +\0 </pre> </li> +</ul> + +<h2> Notes </h2> + +<ul> + <li> s6-uevent-listener is a daemon; it should be run under a proper supervision system such +as <a href="http://skarnet.org/software/s6/">s6</a>. </li> +<li> If you are running s6-uevent-listener, <em>prog...</em> should be the +only program handling uevents, which means that +<tt>/proc/sys/kernel/hotplug</tt> should be empty. </li> + <li> If you want the serialization benefit of the netlink, but still +want to spawn a program such as <a href="http://busybox.net/">busybox</a>'s +or <a href="http://landley.net/toybox/">toybox</a>'s <tt>mdev</tt>, use +<tt><a href="s6-uevent-spawner.html">s6-uevent-spawner</a> mdev</tt> as +s6-uevent-listener's <em>prog</em>. </li> +</ul> + +</body> +</html> diff --git a/doc/s6-uevent-spawner.html b/doc/s6-uevent-spawner.html new file mode 100644 index 0000000..e9be726 --- /dev/null +++ b/doc/s6-uevent-spawner.html @@ -0,0 +1,79 @@ +<html> + <head> + <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> + <meta http-equiv="Content-Language" content="en" /> + <title>s6-linux-utils: the s6-uevent-spawner program</title> + <meta name="Description" content="s6-linux-utils: the s6-uevent-spawner program" /> + <meta name="Keywords" content="s6 linux administration root utilities devd mdev udev hotplug" /> + <!-- <link rel="stylesheet" type="text/css" href="http://skarnet.org/default.css" /> --> + </head> +<body> + +<p> +<a href="index.html">s6-linux-utils</a><br /> +<a href="http://skarnet.org/software/">Software</a><br /> +<a href="http://skarnet.org/">skarnet.org</a> +</p> + +<h1> The <tt>s6-uevent-spawner</tt> program </h1> + +<p> +<tt>s6-uevent-spawner</tt> listens to its standard input for +netlink-style events, and launches a helper program for every event, +similarly to what the hotplug interface does. +</p> + +<p> + It is meant to be used together with +<a href="s6-uevent-listener.html">s6-uevent-listener</a>. +</p> + +<h2> Interface </h2> + +<pre> + s6-uevent-spawner [ -v <em>verbosity</em> ] [ -l <em>linevar</em> ] [ -t <em>l</em>:<em>t</em>:<em>k</em> ] <em>prog...</em> +</pre> + +<ul> + <li> s6-uevent-spawner listens to its stdin for a series of strings +representing kernel uevents, as formatted by +<a href="s6-uevent-listener.html">s6-uevent-listener</a>. </li> + <li> For every event it reads, it spawns <em>prog...</em> with +the event variables added to the environment, just as if <em>prog...</em> +had been registered in <tt>/proc/sys/kernel/hotplug</tt>. However, +it reads the events sequentially, and waits for a <em>prog</em> instance +to finish before spawning another one. </li> + <li> When s6-uevent-spawner receives EOF: if an instance of +<em>prog</em> is alive, it first waits for it to die. Then it exits +0. </li> +</ul> + +<h2> Options </h2> + +<ul> + <li> <tt>-v</tt> <em>verbosity</em> : be more or less verbose. +Default verbosity is 1. 0 only prints fatal error messages. 3 is too much. </li> + <li> <tt>-l</tt> <em>linevar</em> : make the event description +(i.e. the first string in the netlink message announcing the event) +available in <em>prog</em> under the environment variable <em>linevar</em>. +By default, this first string is ignored - it is not needed, all the +event information is already in the other variables. </li> + <li> <tt>-t</tt> <em>l:t:k</em> : If <em>l</em>, <em>t</em> or <em>k</em> is +specified, they specify timeouts; by default, they are infinite. +If <em>prog...</em> is still alive after <em>l</em> milliseconds, s6-devd sends +it a SIGTERM. Then, if <em>prog...</em> is still alive after <em>t</em> more +milliseconds, s6-devd sends it a SIGKILL. Then, if <em>prog...</em> is still +alive after <em>k</em> more milliseconds, s6-uevent-spawner yells and exits 99. </li> +</ul> + +<h2> Notes </h2> + +<ul> + <li> The <em>prog...</em> helper should be very short-lived, +even if you are not using the <tt>-t</tt> option to s6-devd. Since helpers are +spawned sequentially, slow helpers can make events queue up and fill up +buffers. </li> +</ul> + +</body> +</html> diff --git a/doc/upgrade.html b/doc/upgrade.html index b9dcfeb..847324d 100644 --- a/doc/upgrade.html +++ b/doc/upgrade.html @@ -17,6 +17,17 @@ <h1> What has changed in s6-linux-utils </h1> +<h2> in 2.0.2.0 </h2> + +<ul> + <li> skalibs dependency bumped to 2.3.1.1 </li> + <li> New commands: +<a href="s6-uevent-listener.html">s6-uevent-listener</a> and +<a href="s6-uevent-spawner.html">s6-uevent-spawner</a> <li> + <li> <a href="s6-devd.html">s6-devd</a> is now a wrapper +around those commands. </li> +</ul> + <h2> in 2.0.1.0 </h2> <ul> diff --git a/package/deps.mak b/package/deps.mak index c85b123..c013b69 100644 --- a/package/deps.mak +++ b/package/deps.mak @@ -3,7 +3,7 @@ # src/minutils/s6-chroot.o src/minutils/s6-chroot.lo: src/minutils/s6-chroot.c -src/minutils/s6-devd.o src/minutils/s6-devd.lo: src/minutils/s6-devd.c +src/minutils/s6-devd.o src/minutils/s6-devd.lo: src/minutils/s6-devd.c src/include/s6-linux-utils/config.h src/minutils/s6-freeramdisk.o src/minutils/s6-freeramdisk.lo: src/minutils/s6-freeramdisk.c src/minutils/s6-halt.o src/minutils/s6-halt.lo: src/minutils/s6-halt.c src/minutils/s6-hiercopy.o src/minutils/s6-hiercopy.lo: src/minutils/s6-hiercopy.c @@ -16,6 +16,8 @@ src/minutils/s6-ps.o src/minutils/s6-ps.lo: src/minutils/s6-ps.c src/minutils/s6 src/minutils/s6-reboot.o src/minutils/s6-reboot.lo: src/minutils/s6-reboot.c src/minutils/s6-swapoff.o src/minutils/s6-swapoff.lo: src/minutils/s6-swapoff.c src/minutils/s6-swapon.o src/minutils/s6-swapon.lo: src/minutils/s6-swapon.c +src/minutils/s6-uevent-listener.o src/minutils/s6-uevent-listener.lo: src/minutils/s6-uevent-listener.c +src/minutils/s6-uevent-spawner.o src/minutils/s6-uevent-spawner.lo: src/minutils/s6-uevent-spawner.c src/minutils/s6-umount.o src/minutils/s6-umount.lo: src/minutils/s6-umount.c src/minutils/s6ps_grcache.o src/minutils/s6ps_grcache.lo: src/minutils/s6ps_grcache.c src/minutils/s6-ps.h src/minutils/s6ps_otree.o src/minutils/s6ps_otree.lo: src/minutils/s6ps_otree.c src/minutils/s6-ps.h @@ -51,5 +53,9 @@ s6-swapoff: private EXTRA_LIBS := s6-swapoff: src/minutils/s6-swapoff.o -lskarnet s6-swapon: private EXTRA_LIBS := s6-swapon: src/minutils/s6-swapon.o -lskarnet +s6-uevent-listener: private EXTRA_LIBS := +s6-uevent-listener: src/minutils/s6-uevent-listener.o -lskarnet +s6-uevent-spawner: private EXTRA_LIBS := +s6-uevent-spawner: src/minutils/s6-uevent-spawner.o -lskarnet s6-umount: private EXTRA_LIBS := s6-umount: src/minutils/s6-umount.o -lskarnet diff --git a/package/info b/package/info index f55a688..79f07d5 100644 --- a/package/info +++ b/package/info @@ -1,4 +1,4 @@ package=s6-linux-utils -version=2.0.1.0 +version=2.0.2.0 category=admin package_macro_name=S6_LINUX_UTILS diff --git a/package/modes b/package/modes index 9a1c3b1..3905269 100644 --- a/package/modes +++ b/package/modes @@ -1,14 +1,16 @@ -s6-chroot 0700 -s6-devd 0700 -s6-freeramdisk 0700 -s6-halt 0700 -s6-hostname 0755 -s6-logwatch 0755 -s6-mount 0700 -s6-pivotchroot 0700 -s6-poweroff 0700 -s6-ps 0755 -s6-reboot 0700 -s6-swapoff 0700 -s6-swapon 0700 -s6-umount 0700 +s6-chroot 0700 +s6-devd 0700 +s6-uevent-listener 0700 +s6-uevent-spawner 0755 +s6-freeramdisk 0700 +s6-halt 0700 +s6-hostname 0755 +s6-logwatch 0755 +s6-mount 0700 +s6-pivotchroot 0700 +s6-poweroff 0700 +s6-ps 0755 +s6-reboot 0700 +s6-swapoff 0700 +s6-swapon 0700 +s6-umount 0700 diff --git a/package/targets.mak b/package/targets.mak index f03db13..14bc019 100644 --- a/package/targets.mak +++ b/package/targets.mak @@ -1,6 +1,8 @@ BIN_TARGETS := \ s6-chroot \ s6-devd \ +s6-uevent-listener \ +s6-uevent-spawner \ s6-freeramdisk \ s6-halt \ s6-hostname \ diff --git a/src/minutils/deps-exe/s6-uevent-listener b/src/minutils/deps-exe/s6-uevent-listener new file mode 100644 index 0000000..e7187fe --- /dev/null +++ b/src/minutils/deps-exe/s6-uevent-listener @@ -0,0 +1 @@ +-lskarnet diff --git a/src/minutils/deps-exe/s6-uevent-spawner b/src/minutils/deps-exe/s6-uevent-spawner new file mode 100644 index 0000000..e7187fe --- /dev/null +++ b/src/minutils/deps-exe/s6-uevent-spawner @@ -0,0 +1 @@ +-lskarnet diff --git a/src/minutils/s6-devd.c b/src/minutils/s6-devd.c index f51550c..9df5c80 100644 --- a/src/minutils/s6-devd.c +++ b/src/minutils/s6-devd.c @@ -1,281 +1,96 @@ /* ISC license. */ -#ifndef _GNU_SOURCE -#define _GNU_SOURCE -#endif - -#include <sys/types.h> -#include <unistd.h> -#include <spawn.h> -#include <signal.h> -#include <sys/socket.h> -#include <linux/netlink.h> -#include <errno.h> -#include <skalibs/allreadwrite.h> -#include <skalibs/bytestr.h> #include <skalibs/uint.h> #include <skalibs/sgetopt.h> #include <skalibs/strerr2.h> -#include <skalibs/tai.h> -#include <skalibs/iopause.h> -#include <skalibs/env.h> #include <skalibs/djbunix.h> -#include <skalibs/sig.h> -#include <skalibs/selfpipe.h> +#include <s6-linux-utils/config.h> -#define USAGE "s6-devd [ -q | -v ] [ -b kbufsz ] [ -t maxlife:maxterm:maxkill ] helperprogram..." +#define USAGE "s6-devd [ -q | -v ] [ -b kbufsz ] [ -l linevar ] [ -t maxlife:maxterm:maxkill ] helperprogram..." #define dieusage() strerr_dieusage(100, USAGE) -static unsigned int cont = 1, state = 0, verbosity = 1 ; -static pid_t pid ; -static tain_t lifetto = TAIN_INFINITE_RELATIVE, - termtto = TAIN_INFINITE_RELATIVE, - killtto = TAIN_INFINITE_RELATIVE, - deadline ; - -static inline int fd_recvmsg (int fd, struct msghdr *hdr) -{ - int r ; - do r = recvmsg(fd, hdr, 0) ; - while ((r == -1) && (errno == EINTR)) ; - return r ; -} - -static inline int netlink_init (unsigned int kbufsz) -{ - struct sockaddr_nl nl = { .nl_family = AF_NETLINK, .nl_pad = 0, .nl_groups = 1, .nl_pid = 0 } ; - int fd = socket_internal(AF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT, DJBUNIX_FLAG_NB|DJBUNIX_FLAG_COE) ; - if (fd < 0) return -1 ; - if (bind(fd, (struct sockaddr *)&nl, sizeof(struct sockaddr_nl)) < 0) goto err ; - if (setsockopt(fd, SOL_SOCKET, SO_RCVBUFFORCE, &kbufsz, sizeof(unsigned int)) < 0) goto err ; - return fd ; - err: - { - register int e = errno ; - fd_close(fd) ; - errno = e ; - } - return -1 ; -} - -static inline void on_death (void) -{ - pid = 0 ; - state = 0 ; - tain_add_g(&deadline, &tain_infinite_relative) ; - if (cont == 2) cont = 0 ; -} - -static inline void on_event (char const *const *argv, char const *const *envp, char const *s, unsigned int len) -{ - unsigned int envlen = env_len(envp) ; - unsigned int n = envlen + 1 + byte_count(s, len, '\0') ; - int e ; - char const *v[n] ; - if (!env_merge(v, n, envp, envlen, s, len)) - strerr_diefu1sys(111, "env_merge") ; - e = posix_spawnp(&pid, argv[0], 0, 0, (char *const *)argv, (char * const *)v) ; - if (e) { errno = e ; strerr_diefu2sys(111, "spawn ", argv[0]) ; } - state = 1 ; - tain_add_g(&deadline, &lifetto) ; -} - -static inline void handle_timeout (void) +static inline int check_targ (char const *s) { - switch (state) - { - case 0 : - tain_add_g(&deadline, &tain_infinite_relative) ; - break ; - case 1 : - kill(pid, SIGTERM) ; - tain_add_g(&deadline, &termtto) ; - state++ ; - break ; - case 2 : - kill(pid, SIGKILL) ; - tain_add_g(&deadline, &killtto) ; - state++ ; - break ; - case 3 : - strerr_dief1x(99, "child resisted SIGKILL - check your kernel logs.") ; - default : - strerr_dief1x(101, "internal error: inconsistent state. Please submit a bug-report.") ; - } -} - -static inline void handle_signals (void) -{ - for (;;) - { - char c = selfpipe_read() ; - switch (c) - { - case -1 : strerr_diefu1sys(111, "selfpipe_read") ; - case 0 : return ; - case SIGTERM : - cont = pid ? 2 : 0 ; - break ; - case SIGCHLD : - if (!pid) wait_reap() ; - else - { - int wstat ; - int r = wait_pid_nohang(pid, &wstat) ; - if (r < 0) - if (errno != ECHILD) strerr_diefu1sys(111, "wait_pid_nohang") ; - else break ; - else if (!r) break ; - on_death() ; - } - break ; - default : - strerr_dief1x(101, "internal error: inconsistent signal state. Please submit a bug-report.") ; - } - } -} - -static inline void handle_netlink (int fd, char const *const *argv, char const *const *envp) -{ - char buf[4096] ; - int r ; - { - struct sockaddr_nl nl; - struct iovec iov = { .iov_base = &buf, .iov_len = sizeof(buf) } ; - char ctlmsg[CMSG_SPACE(sizeof(struct ucred))] ; - struct msghdr msg = { - .msg_name = &nl, - .msg_namelen = sizeof(struct sockaddr_nl), - .msg_iov = &iov, - .msg_iovlen = 1, - .msg_control = ctlmsg, - .msg_controllen = sizeof(ctlmsg), - .msg_flags = 0 - } ; - r = sanitize_read(fd_recvmsg(fd, &msg)) ; - if (r < 0) - { - if (errno == EPIPE) - { - if (verbosity >= 2) strerr_warnw1x("received EOF on netlink") ; - cont = 0 ; - return ; - } - else strerr_diefu1sys(111, "receive netlink message") ; - } - if (!r) return ; - if (r < 32 || r > 4096) - { - if (verbosity >= 2) - strerr_warnw2x("received and ignored netlink message ", "with invalid length") ; - return ; - } - if (nl.nl_pid) - { - if (verbosity >= 3) - { - char fmt[UINT_FMT] ; - fmt[uint_fmt(fmt, nl.nl_pid)] = 0 ; - strerr_warnw3x("received and ignored netlink message ", "from userspace process ", fmt) ; - } - return ; - } - } - { - unsigned int start = str_len(buf) + 1 ; - if (start < 5 || start > (unsigned int)r) - { - if (verbosity >= 2) - strerr_warnw3x("received and ignored netlink message ", "with invalid header", " length") ; - return ; - } - if (str_strn(buf, start, "@/", 2) >= start) - { - if (verbosity >= 2) - strerr_warnw2x("received and ignored netlink message ", "with invalid header") ; - return ; - } - on_event(argv, envp, buf + start, r - start) ; - } -} - -static inline int make_ttos (char const *s) -{ - unsigned int tlife = 0, tterm = 0, tkill = 0, pos = 0 ; - pos += uint_scan(s + pos, &tlife) ; + unsigned int t = 0, pos = 0 ; + pos += uint_scan(s + pos, &t) ; if (s[pos] && s[pos++] != ':') return 0 ; - if (!tlife) return 1 ; - tain_from_millisecs(&lifetto, tlife) ; - pos += uint_scan(s + pos, &tterm) ; + if (!t) return 1 ; + pos += uint_scan(s + pos, &t) ; if (s[pos] && s[pos++] != ':') return 0 ; - if (!tterm) return 1 ; - tain_from_millisecs(&termtto, tterm) ; - tain_add(&termtto, &termtto, &lifetto) ; - pos += uint_scan(s + pos, &tkill) ; + if (!t) return 1 ; + pos += uint_scan(s + pos, &t) ; if (s[pos]) return 0 ; - if (!tkill) return 1 ; - tain_from_millisecs(&killtto, tkill) ; - tain_add(&killtto, &killtto, &termtto) ; return 1 ; } int main (int argc, char const *const *argv, char const *const *envp) { - iopause_fd x[2] = { { -1, IOPAUSE_READ, 0 }, { -1, IOPAUSE_READ, 0 } } ; + unsigned int kbufsz = 65536, verbosity = 1 ; + char const *linevar = 0 ; + char const *targ = 0 ; PROG = "s6-devd" ; { - unsigned int kbufsz = 65536 ; subgetopt_t l = SUBGETOPT_ZERO ; for (;;) { - register int opt = subgetopt_r(argc, argv, "qvb:t:", &l) ; + register int opt = subgetopt_r(argc, argv, "qvb:l:t:", &l) ; if (opt == -1) break ; switch (opt) { case 'q' : if (verbosity) verbosity-- ; break ; case 'v' : verbosity++ ; break ; case 'b' : if (!uint0_scan(l.arg, &kbufsz)) dieusage() ; break ; - case 't' : if (!make_ttos(l.arg)) dieusage() ; break ; + case 'l' : linevar = l.arg ; break ; + case 't' : if (!check_targ(l.arg)) dieusage() ; targ = l.arg ; break ; default : dieusage() ; } } argc -= l.ind ; argv += l.ind ; - if (!argc) strerr_dieusage(100, USAGE) ; - close(0) ; - if (open_readb("/dev/null") < 0) strerr_diefu1sys(111, "open /dev/null for reading") ; - x[1].fd = netlink_init(kbufsz) ; - if (x[1].fd < 0) strerr_diefu1sys(111, "init netlink") ; - } - - x[0].fd = selfpipe_init() ; - if (x[0].fd == -1) strerr_diefu1sys(111, "init selfpipe") ; - if (sig_ignore(SIGPIPE) < 0) strerr_diefu1sys(111, "ignore SIGPIPE") ; - { - sigset_t set ; - sigemptyset(&set) ; - sigaddset(&set, SIGTERM) ; - sigaddset(&set, SIGCHLD) ; - if (selfpipe_trapset(&set) < 0) strerr_diefu1sys(111, "trap signals") ; } + if (!argc) strerr_dieusage(100, USAGE) ; - tain_now_g() ; - tain_add_g(&deadline, &tain_infinite_relative) ; - if (verbosity >= 2) strerr_warni1x("starting") ; - - while (cont) { - register int r = iopause_g(x, 1 + !pid, &deadline) ; - if (r < 0) strerr_diefu1sys(111, "iopause") ; - else if (!r) handle_timeout() ; - else + unsigned int m = 0, pos = 0 ; + char fmt[UINT_FMT * 3] ; + char const *newargv[argc + 15] ; + newargv[m++] = S6_LINUX_UTILS_BINPREFIX "s6-uevent-listener" ; + if (verbosity != 1) + { + newargv[m++] = "-v" ; + newargv[m++] = fmt + pos ; + pos += uint_fmt(fmt + pos, verbosity) ; + fmt[pos++] = 0 ; + } + if (kbufsz != 65536) + { + newargv[m++] = "-k" ; + newargv[m++] = fmt + pos ; + pos += uint_fmt(fmt + pos, kbufsz) ; + fmt[pos++] = 0 ; + } + newargv[m++] = "--" ; + newargv[m++] = S6_LINUX_UTILS_BINPREFIX "s6-uevent-spawner" ; + if (verbosity != 1) + { + newargv[m++] = "-v" ; + newargv[m++] = fmt + pos ; + pos += uint_fmt(fmt + pos, verbosity) ; + fmt[pos++] = 0 ; + } + if (linevar) + { + newargv[m++] = "-l" ; + newargv[m++] = linevar ; + } + if (targ) { - if ((x[0].revents | x[1].revents) & IOPAUSE_EXCEPT) - strerr_diefu1x(111, "iopause: trouble with pipes") ; - if (x[0].revents & IOPAUSE_READ) handle_signals() ; - else if (!pid && (x[1].revents & IOPAUSE_READ)) - handle_netlink(x[1].fd, argv, envp) ; + newargv[m++] = "-t" ; + newargv[m++] = targ ; } + newargv[m++] = "--" ; + while (*argv) newargv[m++] = *argv++ ; + newargv[m++] = 0 ; + pathexec_run(newargv[0], newargv, envp) ; + strerr_dieexec(111, newargv[0]) ; } - if (verbosity >= 2) strerr_warni1x("exiting") ; - return 0 ; } diff --git a/src/minutils/s6-uevent-listener.c b/src/minutils/s6-uevent-listener.c new file mode 100644 index 0000000..b2cf455 --- /dev/null +++ b/src/minutils/s6-uevent-listener.c @@ -0,0 +1,233 @@ +/* ISC license. */ + +#ifndef _GNU_SOURCE +#define _GNU_SOURCE +#endif + +#include <sys/types.h> +#include <unistd.h> +#include <errno.h> +#include <signal.h> +#include <sys/socket.h> +#include <sys/wait.h> +#include <asm/types.h> +#include <linux/netlink.h> +#include <skalibs/allreadwrite.h> +#include <skalibs/bytestr.h> +#include <skalibs/uint.h> +#include <skalibs/sgetopt.h> +#include <skalibs/strerr2.h> +#include <skalibs/iopause.h> +#include <skalibs/bufalloc.h> +#include <skalibs/djbunix.h> +#include <skalibs/sig.h> +#include <skalibs/selfpipe.h> + +#define USAGE "s6-uevent-listener [ -v verbosity ] [ -b kbufsz ] helperprogram..." +#define dieusage() strerr_dieusage(100, USAGE) +#define dienomem() strerr_diefu1sys(111, "build string") ; + +static unsigned int cont = 1, verbosity = 1 ; +static pid_t pid ; + +static inline int fd_recvmsg (int fd, struct msghdr *hdr) +{ + int r ; + do r = recvmsg(fd, hdr, MSG_DONTWAIT) ; + while ((r == -1) && (errno == EINTR)) ; + return r ; +} + +static inline int netlink_init_stdin (unsigned int kbufsz) +{ + struct sockaddr_nl nl = { .nl_family = AF_NETLINK, .nl_pad = 0, .nl_groups = 0, .nl_pid = 0 } ; + close(0) ; + return socket_internal(AF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT, DJBUNIX_FLAG_NB|DJBUNIX_FLAG_COE) == 0 + && bind(0, (struct sockaddr *)&nl, sizeof(struct sockaddr_nl)) == 0 + && setsockopt(0, SOL_SOCKET, SO_RCVBUFFORCE, &kbufsz, sizeof(unsigned int)) == 0 ; +} + +static inline void handle_signals (void) +{ + for (;;) + { + char c = selfpipe_read() ; + switch (c) + { + case -1 : strerr_diefu1sys(111, "selfpipe_read") ; + case 0 : return ; + case SIGTERM : + cont = 0 ; + fd_close(0) ; + break ; + case SIGCHLD : + { + char fmt[UINT_FMT] ; + int wstat ; + int r = wait_pid_nohang(pid, &wstat) ; + if (r < 0) + if (errno != ECHILD) strerr_diefu1sys(111, "wait_pid_nohang") ; + else break ; + else if (!r) break ; + if (WIFSIGNALED(wstat)) + { + fmt[uint_fmt(fmt, WTERMSIG(wstat))] = 0 ; + strerr_dief2x(1, "child crashed with signal ", fmt) ; + } + else + { + fmt[uint_fmt(fmt, WEXITSTATUS(wstat))] = 0 ; + strerr_dief2x(1, "child exited ", fmt) ; + } + } + default : + strerr_dief1x(101, "internal error: inconsistent signal state. Please submit a bug-report.") ; + } + } +} + +static void doit (char const *s, unsigned int len) +{ + if (!bufalloc_put(bufalloc_1, s, len)) dienomem() ; +} + +static void terminate (void) +{ + if (!bufalloc_put(bufalloc_1, "", 1)) dienomem() ; +} + +static inline void handle_netlink (void) +{ + char buf[8192] ; + static int inmulti = 0 ; + struct sockaddr_nl nl; + struct iovec iov = { .iov_base = &buf, .iov_len = sizeof(buf) } ; + struct msghdr msg = + { + .msg_name = &nl, + .msg_namelen = sizeof(struct sockaddr_nl), + .msg_iov = &iov, + .msg_iovlen = 1, + .msg_control = 0, + .msg_controllen = 0, + .msg_flags = 0 + } ; + struct nlmsghdr *nlh = (struct nlmsghdr *)buf ; + int r = sanitize_read(fd_recvmsg(0, &msg)) ; + if (r < 0) + { + if (errno == EPIPE) + { + if (verbosity >= 2) strerr_warnw1x("received EOF on netlink") ; + cont = 0 ; + fd_close(0) ; + return ; + } + else strerr_diefu1sys(111, "receive netlink message") ; + } + if (!r) return ; + if (msg.msg_flags & MSG_TRUNC) + strerr_diefu2x(111, "buffer too small for ", "netlink message") ; + if (nl.nl_pid) + { + if (verbosity >= 3) + { + char fmt[UINT_FMT] ; + fmt[uint_fmt(fmt, nl.nl_pid)] = 0 ; + strerr_warnw3x("netlink message", " from userspace process ", fmt) ; + } + return ; + } + + for (; NLMSG_OK(nlh, r) ; nlh = NLMSG_NEXT(nlh, r)) + switch (nlh->nlmsg_type) + { + case NLMSG_NOOP : break ; + case NLMSG_ERROR : + if (verbosity >= 3) + strerr_warnw2x("spurious NLMSG_ERROR ", "netlink message") ; + break ; + case NLMSG_DONE : + if (inmulti) + { + inmulti = 0 ; + terminate() ; + } + else if (verbosity >= 3) + strerr_warnw2x("spurious NLMSG_DONE ", "netlink message") ; + break ; + default : + if (nlh->nlmsg_flags & NLM_F_MULTI) inmulti = 1 ; + else if (inmulti) + { + inmulti = 0 ; + terminate() ; + if (verbosity >= 3) + strerr_warnw2x("unterminated multipart ", "netlink message") ; + } + doit(NLMSG_DATA(nlh), (unsigned int)NLMSG_PAYLOAD(nlh, r)) ; + if (!inmulti) terminate() ; + break ; + } +} + +int main (int argc, char const *const *argv, char const *const *envp) +{ + iopause_fd x[3] = { { .events = IOPAUSE_READ }, { .fd = 1 }, { .fd = 0, .events = IOPAUSE_READ } } ; + PROG = "s6-uevent-listener" ; + { + unsigned int kbufsz = 65536 ; + subgetopt_t l = SUBGETOPT_ZERO ; + for (;;) + { + register int opt = subgetopt_r(argc, argv, "v:b:", &l) ; + if (opt == -1) break ; + switch (opt) + { + case 'v' : if (!uint0_scan(l.arg, &verbosity)) dieusage() ; break ; + case 'b' : if (!uint0_scan(l.arg, &kbufsz)) dieusage() ; break ; + default : dieusage() ; + } + } + argc -= l.ind ; argv += l.ind ; + if (!argc) strerr_dieusage(100, USAGE) ; + if (!netlink_init_stdin(kbufsz)) strerr_diefu1sys(111, "init netlink") ; + } + + x[0].fd = selfpipe_init() ; + if (x[0].fd < 0) strerr_diefu1sys(111, "init selfpipe") ; + if (sig_ignore(SIGPIPE) < 0) strerr_diefu1sys(111, "ignore SIGPIPE") ; + { + sigset_t set ; + sigemptyset(&set) ; + sigaddset(&set, SIGTERM) ; + sigaddset(&set, SIGCHLD) ; + if (selfpipe_trapset(&set) < 0) strerr_diefu1sys(111, "trap signals") ; + } + + { + int fd ; + pid = child_spawn1_pipe(argv[0], argv, envp, &fd, 0) ; + if (!pid) strerr_diefu2sys(111, "spawn ", argv[0]) ; + if (fd_move(1, fd) < 0) strerr_diefu1sys(111, "move pipe to stdout") ; + } + + if (verbosity >= 2) strerr_warni1x("starting") ; + + while (cont || bufalloc_len(bufalloc_1)) + { + register int r ; + x[1].events = bufalloc_len(bufalloc_1) ? IOPAUSE_WRITE : 0 ; + r = iopause(x, 2 + cont, 0, 0) ; + if (r < 0) strerr_diefu1sys(111, "iopause") ; + if (!r) continue ; + if (x[0].revents & IOPAUSE_EXCEPT) + strerr_diefu1x(111, "iopause: trouble with selfpipe") ; + if (x[0].revents & IOPAUSE_READ) handle_signals() ; + if (x[1].revents & IOPAUSE_WRITE) + if (!bufalloc_flush(bufalloc_1)) strerr_diefu1sys(111, "flush stdout") ; + if (cont && x[2].revents & IOPAUSE_READ) handle_netlink() ; + } + if (verbosity >= 2) strerr_warni1x("exiting") ; + return 0 ; +} diff --git a/src/minutils/s6-uevent-spawner.c b/src/minutils/s6-uevent-spawner.c new file mode 100644 index 0000000..b074f1f --- /dev/null +++ b/src/minutils/s6-uevent-spawner.c @@ -0,0 +1,234 @@ +/* ISC license. */ + +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <unistd.h> +#include <spawn.h> +#include <signal.h> +#include <errno.h> +#include <stdlib.h> +#include <skalibs/config.h> +#include <skalibs/allreadwrite.h> +#include <skalibs/buffer.h> +#include <skalibs/bytestr.h> +#include <skalibs/uint.h> +#include <skalibs/sgetopt.h> +#include <skalibs/strerr2.h> +#include <skalibs/tai.h> +#include <skalibs/iopause.h> +#include <skalibs/env.h> +#include <skalibs/stralloc.h> +#include <skalibs/djbunix.h> +#include <skalibs/sig.h> +#include <skalibs/selfpipe.h> +#include <skalibs/skamisc.h> + +#define USAGE "s6-uevent-spawner [ -v verbosity ] [ -l linevar ] [ -t maxlife:maxterm:maxkill ] helperprogram..." +#define dieusage() strerr_dieusage(100, USAGE) +#define dienomem() strerr_diefu1sys(111, "build string") ; + +static unsigned int cont = 1, state = 0, verbosity = 1 ; +static pid_t pid ; +static tain_t lifetto = TAIN_INFINITE_RELATIVE, + termtto = TAIN_INFINITE_RELATIVE, + killtto = TAIN_INFINITE_RELATIVE, + deadline ; + +static inline void on_death (void) +{ + pid = 0 ; + state = 0 ; + tain_add_g(&deadline, &tain_infinite_relative) ; +} + +static inline void on_event (char const *const *argv, char const *const *envp, char const *s, unsigned int len) +{ + posix_spawnattr_t attr ; + posix_spawn_file_actions_t actions ; + unsigned int envlen = env_len(envp) ; + unsigned int n = envlen + 1 + byte_count(s, len, '\0') ; + int e ; + char const *v[n] ; + if (!env_merge(v, n, envp, envlen, s, len)) + strerr_diefu1sys(111, "env_merge") ; + + e = posix_spawnattr_init(&attr) ; + if (e) { errno = e ; strerr_diefu1sys(111, "posix_spawnattr_init") ; } + { + sigset_t set ; + sigemptyset(&set) ; + e = posix_spawnattr_setsigmask(&attr, &set) ; + if (e) { errno = e ; strerr_diefu1sys(111, "posix_spawnattr_setsigmask") ; } + sigfillset(&set) ; + e = posix_spawnattr_setsigdefault(&attr, &set) ; + if (e) { errno = e ; strerr_diefu1sys(111, "posix_spawnattr_setsigdefault") ; } + } + e = posix_spawn_file_actions_init(&actions) ; + if (e) { errno = e ; strerr_diefu1sys(111, "posix_spawn_file_actions_init") ; } + e = posix_spawn_file_actions_addopen(&actions, 0, "/dev/null", O_RDONLY, S_IRUSR) ; + if (e) { errno = e ; strerr_diefu1sys(111, "posix_spawn_file_actions_addopen") ; } + e = posix_spawnp(&pid, argv[0], &actions, &attr, (char *const *)argv, (char * const *)v) ; + if (e) { errno = e ; strerr_diefu2sys(111, "spawn ", argv[0]) ; } + posix_spawn_file_actions_destroy(&actions) ; + posix_spawnattr_destroy(&attr) ; + state = 1 ; + tain_add_g(&deadline, &lifetto) ; +} + +static inline void handle_timeout (void) +{ + switch (state) + { + case 0 : + tain_add_g(&deadline, &tain_infinite_relative) ; + break ; + case 1 : + kill(pid, SIGTERM) ; + tain_add_g(&deadline, &termtto) ; + state++ ; + break ; + case 2 : + kill(pid, SIGKILL) ; + tain_add_g(&deadline, &killtto) ; + state++ ; + break ; + case 3 : + strerr_dief1x(99, "child resisted SIGKILL - check your kernel logs.") ; + default : + strerr_dief1x(101, "internal error: inconsistent state. Please submit a bug-report.") ; + } +} + +static inline void handle_signals (void) +{ + for (;;) + { + char c = selfpipe_read() ; + switch (c) + { + case -1 : strerr_diefu1sys(111, "selfpipe_read") ; + case 0 : return ; + case SIGCHLD : + if (!pid) wait_reap() ; + else + { + int wstat ; + int r = wait_pid_nohang(pid, &wstat) ; + if (r < 0) + if (errno != ECHILD) strerr_diefu1sys(111, "wait_pid_nohang") ; + else break ; + else if (!r) break ; + on_death() ; + } + break ; + default : + strerr_dief1x(101, "internal error: inconsistent signal handling. Please submit a bug-report.") ; + } + } +} + +static inline void handle_stdin (stralloc *sa, char const *linevar, char const *const *argv, char const *const *envp) +{ + for (;;) + { + unsigned int start ; + register int r ; + if (!sa->len && linevar) + if (!stralloc_cats(sa, linevar) || !stralloc_catb(sa, "=", 1)) + dienomem() ; + start = sa->len ; + r = sanitize_read(skagetln(buffer_0, sa, 0)) ; + if (r < 0) + { + cont = 0 ; + if (errno != EPIPE && verbosity) strerr_warnwu1sys("read from stdin") ; + } + if (r <= 0) break ; + if (sa->len == start + 1) + { + start = linevar ? 0 : str_len(sa->s) + 1 ; + if (start >= sa->len) + { + if (verbosity) strerr_warnw1x("empty event!") ; + } + else on_event(argv, envp, sa->s + start, sa->len - 1 - start) ; + sa->len = 0 ; + } + } +} + +static inline int make_ttos (char const *s) +{ + unsigned int tlife = 0, tterm = 0, tkill = 0, pos = 0 ; + pos += uint_scan(s + pos, &tlife) ; + if (s[pos] && s[pos++] != ':') return 0 ; + if (!tlife) return 1 ; + tain_from_millisecs(&lifetto, tlife) ; + pos += uint_scan(s + pos, &tterm) ; + if (s[pos] && s[pos++] != ':') return 0 ; + if (!tterm) return 1 ; + tain_from_millisecs(&termtto, tterm) ; + tain_add(&termtto, &termtto, &lifetto) ; + pos += uint_scan(s + pos, &tkill) ; + if (s[pos]) return 0 ; + if (!tkill) return 1 ; + tain_from_millisecs(&killtto, tkill) ; + tain_add(&killtto, &killtto, &termtto) ; + return 1 ; +} + +int main (int argc, char const *const *argv, char const *const *envp) +{ + iopause_fd x[2] = { { .events = IOPAUSE_READ }, { .fd = 0, .events = IOPAUSE_READ } } ; + char const *linevar = 0 ; + stralloc sa = STRALLOC_ZERO ; + PROG = "s6-uevent-spawner" ; + { + subgetopt_t l = SUBGETOPT_ZERO ; + for (;;) + { + register int opt = subgetopt_r(argc, argv, "l:v:t:", &l) ; + if (opt == -1) break ; + switch (opt) + { + case 'l' : linevar = optarg ; break ; + case 'v' : if (!uint0_scan(l.arg, &verbosity)) dieusage() ; break ; + case 't' : if (!make_ttos(l.arg)) dieusage() ; break ; + default : dieusage() ; + } + } + argc -= l.ind ; argv += l.ind ; + if (!argc) strerr_dieusage(100, USAGE) ; + } + if (linevar && linevar[str_chr(linevar, '=')]) + strerr_dief2x(100, "invalid variable: ", linevar) ; + + x[0].fd = selfpipe_init() ; + if (x[0].fd == -1) strerr_diefu1sys(111, "init selfpipe") ; + if (sig_ignore(SIGPIPE) < 0) strerr_diefu1sys(111, "ignore SIGPIPE") ; + if (selfpipe_trap(SIGCHLD) < 0) strerr_diefu1sys(111, "trap SIGCHLD") ; + if (setenv("PATH", SKALIBS_DEFAULTPATH, 0) < 0) + strerr_diefu1sys(111, "setenv PATH") ; + + tain_now_g() ; + tain_add_g(&deadline, &tain_infinite_relative) ; + if (verbosity >= 2) strerr_warni1x("starting") ; + + while (cont || pid) + { + register int r = iopause_g(x, 1 + (!pid && cont), &deadline) ; + if (r < 0) strerr_diefu1sys(111, "iopause") ; + else if (!r) handle_timeout() ; + else + { + if (x[0].revents & IOPAUSE_EXCEPT) + strerr_diefu1x(111, "iopause: trouble with selfpipe") ; + if (x[0].revents & IOPAUSE_READ) handle_signals() ; + else if (!pid && cont && (x[1].revents & IOPAUSE_READ)) + handle_stdin(&sa, linevar, argv, envp) ; + } + } + if (verbosity >= 2) strerr_warni1x("exiting") ; + return 0 ; +} |