Shawn Landdengit-daemon's --systemd mode allows git-daemon to be connect-activated on one or more addresses or ports. Unlike --inetd[1], git-daemon is not spawned for every connection.
[1]which systemd is compatible with using its Accept=yes mode
Signed-off-by: Shawn Landden <shawn@churchofgit.com> --- Documentation/git-daemon.txt | 49 ++++++++++++++++++++++++++++++---- Makefile | 10 +++++++ daemon.c | 62 +++++++++++++++++++++++++++++++++++++++----- 3 files changed, 110 insertions(+), 11 deletions(-)
Show changes to 3 files +110 −11
Documentation/git-daemon.txt, Makefile, daemon.c
diff --git a/Documentation/git-daemon.txt b/Documentation/git-daemon.txt index a69b361..0eab51b 100644 --- a/Documentation/git-daemon.txt +++ b/Documentation/git-daemon.txt @@ -19,7 +19,8 @@ SYNOPSIS [--access-hook=<path>] [--[no-]informative-errors] [--inetd | [--listen=<host_or_ipaddr>] [--port=<n>] - [--user=<user> [--group=<group>]]] + [--systemd | + [--user=<user> [--group=<group>]]] [<directory>...] DESCRIPTION @@ -81,8 +82,8 @@ OPTIONS --inetd:: Have the server run as an inetd service. Implies --syslog. - Incompatible with --detach, --port, --listen, --user and --group - options. + Incompatible with --systemd, --detach, --port, --listen, --user and + --group options. --listen=<host_or_ipaddr>:: Listen on a specific IP address or hostname. IP addresses can @@ -146,8 +147,8 @@ OPTIONS the option are given to `getpwnam(3)` and `getgrnam(3)` and numeric IDs are not supported. + -Giving these options is an error when used with `--inetd`; use -the facility of inet daemon to achieve the same before spawning +Giving these options is an error when used with `--inetd` or `--systemd`; use +the facility of systemd or the inet daemon to achieve the same before spawning 'git daemon' if needed. + Like many programs that switch user id, the daemon does not reset @@ -180,6 +181,16 @@ Git configuration files in that directory are readable by `<user>`. errors are not enabled, all errors report "access denied" to the client. The default is --no-informative-errors. +--systemd:: + For running git-daemon under systemd(1) which will pass + an open connection. This is similar to --inetd, except + that more than one address/port can be listened to at once + both through systemd and through --listen/--port, and git-daemon + doesn't get invoked for every connection, but only the first. + For more details see systemd.socket(5). Incompatible with + --inetd, --detach, --user and --group options. + Works with the session manager (systemd --user) too. + --access-hook=<path>:: Every time a client connects, first run an external command specified by the <path> with service name (e.g. "upload-pack"), @@ -305,6 +316,34 @@ selectively enable/disable services per repository:: uploadarch = true ---------------------------------------------------------------- +systemd configuration example:: +Example systemd configuration files, typically placed in `/etc/systemd/system` +or `$HOME/.config/systemd/user`. ++ +`git-daemon.socket` ++ +---------------------------------------------------------------- +[Unit] +Description=Git Daemon socket + +[Socket] +ListenStream=9418 + +[Install] +WantedBy=sockets.target +---------------------------------------------------------------- ++ +`git-daemon.service` ++ +---------------------------------------------------------------- +[Unit] +Description=Git Daemon + +[Service] +ExecStart=/usr/lib/git-core/git-daemon --systemd --reuseaddr --base-path=/var/lib /var/lib/git +User=git-daemon +StandardError=null +---------------------------------------------------------------- ENVIRONMENT ----------- diff --git a/Makefile b/Makefile index 36655d5..54986a0 100644 --- a/Makefile +++ b/Makefile @@ -42,6 +42,9 @@ all:: # Define NO_EXPAT if you do not have expat installed. git-http-push is # not built, and you cannot push using http:// and https:// transports (dumb). # +# Define NO_SYSTEMD to prevent systemd socket activation support from being +# built into git-daemon. +# # Define EXPATDIR=/foo/bar if your expat header and library files are in # /foo/bar/include and /foo/bar/lib directories. # @@ -997,6 +1000,13 @@ ifeq ($(uname_S),Darwin) PTHREAD_LIBS = endif +ifndef NO_SYSTEMD + ifeq ($(shell echo "\#include <systemd/sd-daemon.h>" | $(CC) -E - -o /dev/null 2>/dev/null && echo y),y) + BASIC_CFLAGS += -DHAVE_SYSTEMD + EXTLIBS += -lsystemd + endif +endif + ifndef CC_LD_DYNPATH ifdef NO_R_TO_GCC_LINKER # Some gcc does not accept and pass -R to the linker to specify diff --git a/daemon.c b/daemon.c index d3d3e43..42e1441 100644 --- a/daemon.c +++ b/daemon.c @@ -1,3 +1,7 @@ +#ifdef HAVE_SYSTEMD +# include <systemd/sd-daemon.h> +#endif + #include "cache.h" #include "pkt-line.h" #include "exec_cmd.h" @@ -28,7 +32,11 @@ static const char daemon_usage[] = " [--(enable|disable|allow-override|forbid-override)=<service>]\n" " [--access-hook=<path>]\n" " [--inetd | [--listen=<host_or_ipaddr>] [--port=<n>]\n" +#ifdef HAVE_SYSTEMD +" [--systemd | [--detach] [--user=<user> [--group=<group>]]]\n" /* exactly 80 characters */ +#else " [--detach] [--user=<user> [--group=<group>]]\n" +#endif " [<directory>...]"; /* List of acceptable pathname prefixes */ @@ -1166,12 +1174,40 @@ static struct credentials *prepare_credentials(const char *user_name, } #endif +#ifdef HAVE_SYSTEMD +static int enumerate_sockets(struct socketlist *socklist, struct string_list *listen_addr, int listen_port, int systemd_mode) +{ + if (systemd_mode) { + int i, n; + + n = sd_listen_fds(0); + if (n <= 0) + die("--systemd mode specified and no file descriptors recieved"); + ALLOC_GROW(socklist->list, socklist->nr + n, socklist->alloc); + for (i = 0; i < n; i++) + socklist->list[socklist->nr++] = SD_LISTEN_FDS_START + i; + } + + if (listen_addr->nr > 0 || !systemd_mode) + socksetup(listen_addr, listen_port, socklist); + + return 0; +} +#else +static int enumerate_sockets(struct socketlist *socklist, struct string_list *listen_addr, int listen_port, int systemd_mode) +{ + socksetup(listen_addr, listen_port, socklist); + + return 0; +} +#endif + static int serve(struct string_list *listen_addr, int listen_port, - struct credentials *cred) + struct credentials *cred, int systemd_mode) { struct socketlist socklist = { NULL, 0, 0 }; - socksetup(listen_addr, listen_port, &socklist); + enumerate_sockets(&socklist, listen_addr, listen_port, systemd_mode); if (socklist.nr == 0) die("unable to allocate any listen sockets on port %u", listen_port); @@ -1187,7 +1223,7 @@ int main(int argc, char **argv) { int listen_port = 0; struct string_list listen_addr = STRING_LIST_INIT_NODUP; - int serve_mode = 0, inetd_mode = 0; + int serve_mode = 0, inetd_mode = 0, systemd_mode = 0; const char *pid_file = NULL, *user_name = NULL, *group_name = NULL; int detach = 0; struct credentials *cred = NULL; @@ -1322,6 +1358,12 @@ int main(int argc, char **argv) informative_errors = 0; continue; } +#ifdef HAVE_SYSTEMD + if (!strcmp(arg, "--systemd")) { + systemd_mode = 1; + continue; + } +#endif if (!strcmp(arg, "--")) { ok_paths = &argv[i+1]; break; @@ -1340,8 +1382,16 @@ int main(int argc, char **argv) /* avoid splitting a message in the middle */ setvbuf(stderr, NULL, _IOFBF, 4096); - if (inetd_mode && (detach || group_name || user_name)) - die("--detach, --user and --group are incompatible with --inetd"); + if ((inetd_mode || systemd_mode) && (detach || group_name || user_name)) + die("--detach, --user and --group are incompatible with --inetd and --systemd"); + +#ifdef HAVE_SYSTEMD + if (systemd_mode && inetd_mode) + die("--inetd is incompatible with --systemd"); + + if (systemd_mode && !sd_booted()) + die("--systemd passed and not invoked from systemd"); +#endif if (inetd_mode && (listen_port || (listen_addr.nr > 0))) die("--listen= and --port= are incompatible with --inetd"); @@ -1386,5 +1436,5 @@ int main(int argc, char **argv) cld_argv[i+1] = argv[i]; cld_argv[argc+1] = NULL; - return serve(&listen_addr, listen_port, cred); + return serve(&listen_addr, listen_port, cred, systemd_mode); }
-- 2.2.1.209.g41e5f3a
