diff options
| -rw-r--r-- | doc/s6-fghack.html | 7 | ||||
| -rw-r--r-- | package/deps.mak | 4 | ||||
| -rw-r--r-- | src/daemontools-extras/deps-exe/s6-fghack | 1 | ||||
| -rw-r--r-- | src/daemontools-extras/s6-fghack.c | 67 |
4 files changed, 26 insertions, 53 deletions
diff --git a/doc/s6-fghack.html b/doc/s6-fghack.html index 3f172ef..666448b 100644 --- a/doc/s6-fghack.html +++ b/doc/s6-fghack.html @@ -30,12 +30,13 @@ s6-fghack is an anti-backgrounding tool. <ul> <li> s6-fghack opens a lot of file descriptors (all writing to a single pipe). </li> - <li> Then it forks and executes <em>prog...</em>. </li> + <li> Then it spawns <em>prog...</em> as a child. </li> <li> If something gets written on one of those descriptors, it's a bug in <em>prog</em>. s6-fghack then complains and exits 102. </li> <li> Unless <em>prog...</em> goes out of its way to close descriptors it does not know about, -s6-fghack is able to detect when <em>prog...</em> exits. It exits with the same exit -code (or 111 if <em>prog...</em> has crashed). </li> +s6-fghack is able to detect when <em>prog...</em> exits. It exits with an +<a href="//skarnet.org/software/execline/exitcodes.html">approximation</a> of the same exit +code. </li> </ul> <h2> Notes </h2> diff --git a/package/deps.mak b/package/deps.mak index 751b052..f48a1d2 100644 --- a/package/deps.mak +++ b/package/deps.mak @@ -127,7 +127,7 @@ src/pipe-tools/s6-ftrig-wait.o src/pipe-tools/s6-ftrig-wait.lo: src/pipe-tools/s src/pipe-tools/s6-mkfifodir.o src/pipe-tools/s6-mkfifodir.lo: src/pipe-tools/s6-mkfifodir.c src/include/s6/ftrigw.h src/supervision/s6-notifyoncheck.o src/supervision/s6-notifyoncheck.lo: src/supervision/s6-notifyoncheck.c src/include/s6/s6.h src/supervision/s6-permafailon.o src/supervision/s6-permafailon.lo: src/supervision/s6-permafailon.c src/include/s6/supervise.h -src/supervision/s6-supervise.o src/supervision/s6-supervise.lo: src/supervision/s6-supervise.c src/include/s6/ftrigw.h src/include/s6/supervise.h +src/supervision/s6-supervise.o src/supervision/s6-supervise.lo: src/supervision/s6-supervise.c src/include/s6/config.h src/include/s6/ftrigw.h src/include/s6/supervise.h src/supervision/s6-svc.o src/supervision/s6-svc.lo: src/supervision/s6-svc.c src/include/s6/config.h src/include/s6/supervise.h src/supervision/s6-svdt-clear.o src/supervision/s6-svdt-clear.lo: src/supervision/s6-svdt-clear.c src/include/s6/supervise.h src/supervision/s6-svdt.o src/supervision/s6-svdt.lo: src/supervision/s6-svdt.c src/include/s6/supervise.h @@ -175,7 +175,7 @@ s6-envdir: EXTRA_LIBS := -lskarnet s6-envdir: src/daemontools-extras/s6-envdir.o s6-envuidgid: EXTRA_LIBS := -lskarnet ${MAYBEPTHREAD_LIB} s6-envuidgid: src/daemontools-extras/s6-envuidgid.o ${LIBNSSS} -s6-fghack: EXTRA_LIBS := -lskarnet +s6-fghack: EXTRA_LIBS := -lskarnet ${SPAWN_LIB} s6-fghack: src/daemontools-extras/s6-fghack.o s6-log: EXTRA_LIBS := -lskarnet ${SYSCLOCK_LIB} s6-log: src/daemontools-extras/s6-log.o diff --git a/src/daemontools-extras/deps-exe/s6-fghack b/src/daemontools-extras/deps-exe/s6-fghack index e7187fe..39597dd 100644 --- a/src/daemontools-extras/deps-exe/s6-fghack +++ b/src/daemontools-extras/deps-exe/s6-fghack @@ -1 +1,2 @@ -lskarnet +${SPAWN_LIB} diff --git a/src/daemontools-extras/s6-fghack.c b/src/daemontools-extras/s6-fghack.c index c90792a..fec2962 100644 --- a/src/daemontools-extras/s6-fghack.c +++ b/src/daemontools-extras/s6-fghack.c @@ -7,63 +7,34 @@ #include <skalibs/strerr.h> #include <skalibs/allreadwrite.h> #include <skalibs/djbunix.h> -#include <skalibs/exec.h> +#include <skalibs/cspawn.h> #define USAGE "s6-fghack prog..." -int main (int argc, char const *const *argv) +#define N 30 + +int main (int argc, char const *const *argv, char const *const *envp) { int p[2] ; - int pcoe[2] ; + int fds[N] ; pid_t pid ; - char dummy ; + cspawn_fileaction fa = { .type = CSPAWN_FA_CLOSE } ; + char c ; + PROG = "s6-fghack" ; if (argc < 2) strerr_dieusage(100, USAGE) ; - if (pipe(p) < 0) strerr_diefu1sys(111, "create hackpipe") ; - if (pipe(pcoe) < 0) strerr_diefu1sys(111, "create coepipe") ; - - switch (pid = fork()) - { - case -1 : strerr_diefu1sys(111, "fork") ; - case 0 : - { - int i = 0 ; - close(p[0]) ; - close(pcoe[0]) ; - if (coe(pcoe[1]) < 0) _exit(111) ; - for (; i < 30 ; i++) dup(p[1]) ; /* hack. gcc's warning is justified. */ - exec(argv+1) ; - i = errno ; - if (fd_write(pcoe[1], "", 1) < 1) _exit(111) ; - _exit(i) ; - } - } - + if (pipe(p) == -1) strerr_diefu1sys(111, "create hackpipe") ; + for (size_t i = 0 ; i < N ; i++) + fds[i] = dup(p[1]) ; + fa.x.fd = p[0] ; + pid = cspawn(argv[1], argv + 1, envp, 0, &fa, 1) ; + if (!pid) strerr_diefu2sys(111, "spawn ", argv[1]) ; close(p[1]) ; - close(pcoe[1]) ; + for (size_t i = 0 ; i < N ; i++) close(fds[i]) ; - switch (fd_read(pcoe[0], &dummy, 1)) - { - case -1 : strerr_diefu1sys(111, "read on coepipe") ; - case 1 : - { - int wstat ; - if (wait_pid(pid, &wstat) < 0) strerr_diefu1sys(111, "wait_pid") ; - errno = WEXITSTATUS(wstat) ; - strerr_dieexec(111, argv[1]) ; - } - } - - fd_close(pcoe[0]) ; - - p[1] = fd_read(p[0], &dummy, 1) ; - if (p[1] < 0) strerr_diefu1sys(111, "read on hackpipe") ; + p[1] = fd_read(p[0], &c, 1) ; + if (p[1] == -1) strerr_diefu1sys(111, "read on hackpipe") ; if (p[1]) strerr_dief2x(102, argv[1], " wrote on hackpipe") ; - - { - int wstat ; - if (wait_pid(pid, &wstat) < 0) strerr_diefu1sys(111, "wait_pid") ; - if (WIFSIGNALED(wstat)) strerr_dief2x(111, argv[2], " crashed") ; - return WEXITSTATUS(wstat) ; - } + if (wait_pid(pid, &p[1]) < 0) strerr_diefu1sys(111, "wait_pid") ; + return wait_estatus(p[1]) ; } |