# [v3RFC] systemd socket activation support 2 messages from 2015-04-03 to 2015-04-03. Participants: Shawn Landden, Eric Sunshine. Thread: https://gitlist.dev/t/38996 ## Shawn Landden, 2015-04-03 22:30 Subject: [v3RFC] systemd socket activation support Message-ID: <1428100224-29441-1-git-send-email-shawn@churchofgit.com> URL: https://gitlist.dev/e/1428100224-29441-1-git-send-email-shawn%40churchofgit.com ``` systemd supports git-daemon's existing --inetd mode as well. v2: actually test... v3: make optional, switch to libsystemd shawn@zephyr:~/git/git$ ldd /lib/x86_64-linux-gnu/libsystemd.so.0 linux-vdso.so.1 (0x00007ffeba7ec000) libcap.so.2 => /lib/x86_64-linux-gnu/libcap.so.2 (0x00007fea158fe000) libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007fea155f9000) librt.so.1 => /lib/x86_64-linux-gnu/librt.so.1 (0x00007fea153f0000) libselinux.so.1 => /lib/x86_64-linux-gnu/libselinux.so.1 (0x00007fea151cb000) liblzma.so.5 => /lib/x86_64-linux-gnu/liblzma.so.5 (0x00007fea14fa8000) libgcrypt.so.20 => /lib/x86_64-linux-gnu/libgcrypt.so.20 (0x00007fea14cc5000) libresolv.so.2 => /lib/x86_64-linux-gnu/libresolv.so.2 (0x00007fea14aae000) libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007fea148aa000) libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007fea1468b000) libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007fea142e7000) /lib64/ld-linux-x86-64.so.2 (0x00007fea15d5b000) libattr.so.1 => /lib/x86_64-linux-gnu/libattr.so.1 (0x00007fea140e2000) libpcre.so.3 => /lib/x86_64-linux-gnu/libpcre.so.3 (0x00007fea13e73000) libgpg-error.so.0 => /lib/x86_64-linux-gnu/libgpg-error.so.0 (0x00007fea13c61000) ewwwww...and only for two tiny functions. Signed-off-by: Shawn Landden --- Documentation/git-daemon.txt | 25 ++++++++++++++++++++++++ Makefile | 14 ++++++++++++-- daemon.c | 46 ++++++++++++++++++++++++++++++++++++++------ 3 files changed, 77 insertions(+), 8 deletions(-) diff --git a/Documentation/git-daemon.txt b/Documentation/git-daemon.txt index a69b361..898e01f 100644 --- a/Documentation/git-daemon.txt +++ b/Documentation/git-daemon.txt @@ -20,6 +20,7 @@ SYNOPSIS [--inetd | [--listen=] [--port=] [--user= [--group=]]] + [--systemd] [...] DESCRIPTION @@ -190,6 +191,12 @@ Git configuration files in that directory are readable by ``. exiting with a zero status). It can also look at the $REMOTE_ADDR and $REMOTE_PORT environment variables to learn about the requestor when making this decision. +--systemd:: + For running git-daemon under systemd(1) which will pass + an open connection. This is similar to --inetd, except + that more than one address/port can be listened to at once + both through systemd and through --listen, and git-daemon doesn't get + invoked for every connection. For more details see systemd.socket(5). + The external command can optionally write a single line to its standard output to be sent to the requestor as an error message when @@ -304,7 +311,25 @@ selectively enable/disable services per repository:: uploadpack = false uploadarch = true ---------------------------------------------------------------- ++ +systemd configuration example: + +# /etc/systemd/system/git-daemon.socket +[Unit] +Description=Git Daemon socket + +[Socket] +ListenStream=9418 + +[Install] +WantedBy=sockets.target +# /etc/systemd/system/git-daemon.service +[Unit] +Description=Git Daemon +[Service] +ExecStart=/usr/lib/git-core/git-daemon --systemd --reuseaddr --base-path=/var/lib /var/lib/git +User=gitdaemon ENVIRONMENT ----------- diff --git a/Makefile b/Makefile index 5f3987f..362af94 100644 --- a/Makefile +++ b/Makefile @@ -42,6 +42,9 @@ all:: # Define NO_EXPAT if you do not have expat installed. git-http-push is # not built, and you cannot push using http:// and https:// transports (dumb). # +# Define NO_SYSTEMD to prevent systemd socket activation support from being +# built into git-daemon. +# # Define EXPATDIR=/foo/bar if your expat header and library files are in # /foo/bar/include and /foo/bar/lib directories. # @@ -995,6 +998,13 @@ ifeq ($(uname_S),Darwin) PTHREAD_LIBS = endif +ifndef NO_SYSTEMD + ifeq ($(shell echo "\#include " | $(CC) -E - -o /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 @@ -1403,8 +1413,8 @@ ifdef NATIVE_CRLF endif ifdef USE_NED_ALLOCATOR - COMPAT_CFLAGS += -Icompat/nedmalloc - COMPAT_OBJS += compat/nedmalloc/nedmalloc.o + COMPAT_CFLAGS += -Icompat/nedmalloc + COMPAT_OBJS += compat/nedmalloc/nedmalloc.o endif ifdef GIT_TEST_CMP_USE_COPIED_CONTEXT diff --git a/daemon.c b/daemon.c index 9ee2187..16b9eda 100644 --- a/daemon.c +++ b/daemon.c @@ -1,3 +1,7 @@ +#ifdef HAVE_SYSTEMD +# include +#endif + #include "cache.h" #include "pkt-line.h" #include "exec_cmd.h" @@ -29,6 +33,9 @@ static const char daemon_usage[] = " [--access-hook=]\n" " [--inetd | [--listen=] [--port=]\n" " [--detach] [--user= [--group=]]\n" +#ifdef HAVE_SYSTEMD +" [--systemd]\n" +#endif " [...]"; /* List of acceptable pathname prefixes */ @@ -1176,11 +1183,24 @@ static void store_pid(const char *path) } 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); +#ifdef HAVE_SYSTEMD + if (systemd_mode) { + int i; + int n; + + n = sd_listen_fds(0); + 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) +#endif + socksetup(listen_addr, listen_port, &socklist); if (socklist.nr == 0) die("unable to allocate any listen sockets on port %u", listen_port); @@ -1196,7 +1216,7 @@ 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; @@ -1331,6 +1351,12 @@ 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; @@ -1349,8 +1375,16 @@ 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"); @@ -1395,5 +1429,5 @@ 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 ``` ## Eric Sunshine, 2015-04-03 23:06 Subject: Re: [v3RFC] systemd socket activation support Message-ID: URL: https://gitlist.dev/e/CAPig%2BcTFRz%3Db%3DhdsuP_v_1jzu9-utGEWQM_rkhpEBvq-chrZig%40mail.gmail.com In-Reply-To: <1428100224-29441-1-git-send-email-shawn@churchofgit.com> ``` On Fri, Apr 3, 2015 at 6:30 PM, Shawn Landden wrote: > systemd supports git-daemon's existing --inetd mode as well. > > v2: actually test... > v3: make optional, switch to libsystemd Every issue raised by my review[1] of v2 still applies to v3, so I won't bother repeating them here, however, there is one comment (below) new to this version of the patch. [1]: http://article.gmane.org/gmane.comp.version-control.git/266650 > shawn@zephyr:~/git/git$ ldd /lib/x86_64-linux-gnu/libsystemd.so.0 > linux-vdso.so.1 (0x00007ffeba7ec000) > libcap.so.2 => /lib/x86_64-linux-gnu/libcap.so.2 (0x00007fea158fe000) > libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007fea155f9000) > librt.so.1 => /lib/x86_64-linux-gnu/librt.so.1 (0x00007fea153f0000) > libselinux.so.1 => /lib/x86_64-linux-gnu/libselinux.so.1 (0x00007fea151cb000) > liblzma.so.5 => /lib/x86_64-linux-gnu/liblzma.so.5 (0x00007fea14fa8000) > libgcrypt.so.20 => /lib/x86_64-linux-gnu/libgcrypt.so.20 (0x00007fea14cc5000) > libresolv.so.2 => /lib/x86_64-linux-gnu/libresolv.so.2 (0x00007fea14aae000) > libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007fea148aa000) > libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007fea1468b000) > libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007fea142e7000) > /lib64/ld-linux-x86-64.so.2 (0x00007fea15d5b000) > libattr.so.1 => /lib/x86_64-linux-gnu/libattr.so.1 (0x00007fea140e2000) > libpcre.so.3 => /lib/x86_64-linux-gnu/libpcre.so.3 (0x00007fea13e73000) > libgpg-error.so.0 => /lib/x86_64-linux-gnu/libgpg-error.so.0 (0x00007fea13c61000) > > ewwwww...and only for two tiny functions. > > Signed-off-by: Shawn Landden > --- > diff --git a/Makefile b/Makefile > index 5f3987f..362af94 100644 > --- a/Makefile > +++ b/Makefile > @@ -1403,8 +1413,8 @@ ifdef NATIVE_CRLF > endif > > ifdef USE_NED_ALLOCATOR > - COMPAT_CFLAGS += -Icompat/nedmalloc > - COMPAT_OBJS += compat/nedmalloc/nedmalloc.o > + COMPAT_CFLAGS += -Icompat/nedmalloc > + COMPAT_OBJS += compat/nedmalloc/nedmalloc.o You're sneaking in (whitespace) changes unrelated to the rest of the patch. Typically, such unrelated cleanups should be relegated to separate preparatory patches. (In this case, however, the change is probably unwarranted and likely accidental, but serves as a reminder to review patches before sending them out.) > endif > > ifdef GIT_TEST_CMP_USE_COPIED_CONTEXT > diff --git a/daemon.c b/daemon.c > index 9ee2187..16b9eda 100644 > --- a/daemon.c > +++ b/daemon.c ```