diff options
| -rw-r--r-- | COPYING | 2 | ||||
| -rw-r--r-- | package/deps.mak | 1 | ||||
| -rw-r--r-- | src/include/skalibs/djbunix.h | 16 | ||||
| -rw-r--r-- | src/libstddjb/child_spawn.c | 2 | ||||
| -rw-r--r-- | src/libstddjb/child_spawn3.c | 165 | ||||
| -rw-r--r-- | src/libunixonacid/textclient_startf.c | 4 |
6 files changed, 183 insertions, 7 deletions
@@ -1,4 +1,4 @@ -Copyright (c) 2011-2017 Laurent Bercot <ska-skaware@skarnet.org> +Copyright (c) 2011-2018 Laurent Bercot <ska-skaware@skarnet.org> Permission to use, copy, modify, and distribute this software for any purpose with or without fee is hereby granted, provided that the above diff --git a/package/deps.mak b/package/deps.mak index 6d24535..5f58c9f 100644 --- a/package/deps.mak +++ b/package/deps.mak @@ -276,6 +276,7 @@ src/libstddjb/child_spawn1_internal.o src/libstddjb/child_spawn1_internal.lo: sr src/libstddjb/child_spawn1_pipe.o src/libstddjb/child_spawn1_pipe.lo: src/libstddjb/child_spawn1_pipe.c src/libstddjb/djbunix-internal.h src/include/skalibs/djbunix.h src/libstddjb/child_spawn1_socket.o src/libstddjb/child_spawn1_socket.lo: src/libstddjb/child_spawn1_socket.c src/libstddjb/djbunix-internal.h src/include/skalibs/djbunix.h src/include/skalibs/webipc.h src/libstddjb/child_spawn2.o src/libstddjb/child_spawn2.lo: src/libstddjb/child_spawn2.c src/include/skalibs/allreadwrite.h src/include/skalibs/config.h src/include/skalibs/djbunix.h src/include/skalibs/sig.h src/include/skalibs/strerr2.h src/include/skalibs/sysdeps.h +src/libstddjb/child_spawn3.o src/libstddjb/child_spawn3.lo: src/libstddjb/child_spawn3.c src/include/skalibs/allreadwrite.h src/include/skalibs/config.h src/include/skalibs/djbunix.h src/include/skalibs/env.h src/include/skalibs/sig.h src/include/skalibs/strerr2.h src/include/skalibs/sysdeps.h src/include/skalibs/types.h src/libstddjb/coe.o src/libstddjb/coe.lo: src/libstddjb/coe.c src/include/skalibs/djbunix.h src/libstddjb/deepsleepuntil.o src/libstddjb/deepsleepuntil.lo: src/libstddjb/deepsleepuntil.c src/include/skalibs/iopause.h src/include/skalibs/tai.h src/libstddjb/dir_close.o src/libstddjb/dir_close.lo: src/libstddjb/dir_close.c src/include/skalibs/direntry.h diff --git a/src/include/skalibs/djbunix.h b/src/include/skalibs/djbunix.h index 00d8f00..ebcba18 100644 --- a/src/include/skalibs/djbunix.h +++ b/src/include/skalibs/djbunix.h @@ -183,14 +183,24 @@ extern pid_t child_spawn2 (char const *, char const *const *, char const *const /* - Unified function to fork a child with communication channels (pipes). + Same, with an additional pipe from the child to the parent. + The int * points to 3 fds. + The additional fd# is available to the child in the defined env variable. + */ + +#define SKALIBS_CHILD_SPAWN_FDS_ENVVAR "SKALIBS_CHILD_SPAWN_FDS" + +extern pid_t child_spawn3 (char const *, char const *const *, char const *const *, int *) ; + + + /* + Generalization of the previous functions. * uses posix_spawn() if available, else uses fork+exec - * requests n (the last arg) communication fds between parent and child + * requests n (the last arg) communication fds between parent and child. Uses pipes. * if n=1, equivalent to child_spawn1_pipe; child writes, parent reads. * if n>=2, parent reads on even and writes on odd. */ -#define SKALIBS_CHILD_SPAWN_FDS_ENVVAR "SKALIBS_CHILD_SPAWN_FDS" extern pid_t child_spawn (char const *, char const *const *, char const *const *, int *, unsigned int) ; diff --git a/src/libstddjb/child_spawn.c b/src/libstddjb/child_spawn.c index 82edf8a..964e4e2 100644 --- a/src/libstddjb/child_spawn.c +++ b/src/libstddjb/child_spawn.c @@ -95,7 +95,7 @@ pid_t child_spawn (char const *prog, char const *const *argv, char const *const int haspath = !!getenv("PATH") ; size_t envlen = env_len(envp) ; char const *newenv[envlen + 2] ; - if (!env_merge(newenv, envlen+2, envp, envlen, modifs, m)) goto errsp ; + if (!env_merge(newenv, envlen+2, envp, envlen, modifs, m)) goto erractions ; if (!haspath && (setenv("PATH", SKALIBS_DEFAULTPATH, 0) < 0)) { e = errno ; goto erractions ; diff --git a/src/libstddjb/child_spawn3.c b/src/libstddjb/child_spawn3.c new file mode 100644 index 0000000..82220ea --- /dev/null +++ b/src/libstddjb/child_spawn3.c @@ -0,0 +1,165 @@ +/* ISC license. */ + +/* MT-unsafe */ + +#include <skalibs/sysdeps.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <sys/wait.h> +#include <unistd.h> +#include <errno.h> +#include <signal.h> + +#ifdef SKALIBS_HASPOSIXSPAWN + +#include <stdlib.h> +#include <spawn.h> +#include <skalibs/config.h> + +#else + +#include <string.h> +#include <skalibs/sig.h> +#include <skalibs/strerr2.h> + +#endif + +#include <skalibs/types.h> +#include <skalibs/allreadwrite.h> +#include <skalibs/env.h> +#include <skalibs/djbunix.h> + +pid_t child_spawn3 (char const *prog, char const *const *argv, char const *const *envp, int *fds) +{ +#ifdef SKALIBS_HASPOSIXSPAWN + posix_spawn_file_actions_t actions ; + posix_spawnattr_t attr ; +#else + int syncpipe[2] ; +#endif + int p[3][2] ; + pid_t pid ; + int e ; + size_t m = sizeof(SKALIBS_CHILD_SPAWN_FDS_ENVVAR) ; + char modifs[sizeof(SKALIBS_CHILD_SPAWN_FDS_ENVVAR) + UINT_FMT] = SKALIBS_CHILD_SPAWN_FDS_ENVVAR "=" ; + if (pipe(p[0]) < 0 || ndelay_on(p[0][0]) < 0 || coe(p[0][0]) < 0) return 0 ; + if (pipe(p[1]) < 0 || ndelay_on(p[1][1]) < 0 || coe(p[1][1]) < 0) goto errp0 ; + if (pipe(p[2]) < 0 || ndelay_on(p[2][0]) < 0 || coe(p[2][0]) < 0) goto errp1 ; + m += uint_fmt(modifs + sizeof(SKALIBS_CHILD_SPAWN_FDS_ENVVAR), p[2][1]) ; + modifs[m++] = 0 ; + +#ifdef SKALIBS_HASPOSIXSPAWN + + e = posix_spawnattr_init(&attr) ; + if (e) goto errp2 ; + { + sigset_t set ; + sigemptyset(&set) ; + e = posix_spawnattr_setsigmask(&attr, &set) ; + if (e) goto errattr ; + e = posix_spawnattr_setflags(&attr, POSIX_SPAWN_SETSIGMASK) ; + if (e) goto errattr ; + } + e = posix_spawn_file_actions_init(&actions) ; + if (e) goto errattr ; + e = posix_spawn_file_actions_adddup2(&actions, p[1][0], fds[0]) ; + if (e) goto erractions ; + e = posix_spawn_file_actions_addclose(&actions, p[1][0]) ; + if (e) goto erractions ; + e = posix_spawn_file_actions_adddup2(&actions, p[0][1], fds[1]) ; + if (e) goto erractions ; + e = posix_spawn_file_actions_addclose(&actions, p[0][1]) ; + if (e) goto erractions ; + { + int haspath = !!getenv("PATH") ; + size_t envlen = env_len(envp) ; + char const *newenv[envlen + 2] ; + if (!env_merge(newenv, envlen+2, envp, envlen, modifs, m)) goto erractions ; + if (!haspath && (setenv("PATH", SKALIBS_DEFAULTPATH, 0) < 0)) + { + e = errno ; goto erractions ; + } + e = posix_spawnp(&pid, prog, &actions, &attr, (char *const *)argv, (char *const *)newenv) ; + if (!haspath) unsetenv("PATH") ; + if (e) goto erractions ; + } + + posix_spawn_file_actions_destroy(&actions) ; + posix_spawnattr_destroy(&attr) ; + +#else + if (pipe(syncpipe) < 0) { e = errno ; goto errp2 ; } + if (coe(syncpipe[1]) < 0) { e = errno ; goto errsp ; } + + pid = fork() ; + if (pid < 0) { e = errno ; goto errsp ; } + else if (!pid) + { + size_t len = strlen(PROG) ; + char name[len + 9] ; + memcpy(name, PROG, len) ; + memcpy(name + len, " (child)", 9) ; + PROG = name ; + fd_close(syncpipe[0]) ; + if (fd_move2(fds[0], p[1][0], fds[1], p[0][1]) < 0) goto syncdie ; + sig_blocknone() ; + pathexec_r_name(prog, argv, envp, env_len(envp), modifs, m) ; + + syncdie: + { + char c = errno ; + fd_write(syncpipe[1], &c, 1) ; + } + _exit(127) ; + } + + fd_close(syncpipe[1]) ; + { + char c ; + syncpipe[1] = fd_read(syncpipe[0], &c, 1) ; + if (syncpipe[1]) + { + if (syncpipe[1] < 0) e = errno ; + else + { + kill(pid, SIGKILL) ; + e = c ; + } + wait_pid(pid, &syncpipe[1]) ; + goto errsp0 ; + } + } + fd_close(syncpipe[0]) ; +#endif + + fd_close(p[2][1]) ; + fd_close(p[1][0]) ; + fd_close(p[0][1]) ; + fds[0] = p[0][0] ; + fds[1] = p[1][1] ; + fds[2] = p[2][0] ; + return pid ; + +#ifdef SKALIBS_HASPOSIXSPAWN + erractions: + posix_spawn_file_actions_destroy(&actions) ; + errattr: + posix_spawnattr_destroy(&attr) ; +#endif +#ifndef SKALIBS_HASPOSIXSPAWN + errsp: + fd_close(syncpipe[1]) ; + errsp0: + fd_close(syncpipe[0]) ; +#endif + errp2: + fd_close(p[2][1]) ; + fd_close(p[2][0]) ; + errp1: + fd_close(p[1][1]) ; + fd_close(p[1][0]) ; + errp0: + fd_close(p[0][1]) ; + fd_close(p[0][0]) ; + return 0 ; +} diff --git a/src/libunixonacid/textclient_startf.c b/src/libunixonacid/textclient_startf.c index fd724cd..6a6f0fc 100644 --- a/src/libunixonacid/textclient_startf.c +++ b/src/libunixonacid/textclient_startf.c @@ -12,8 +12,8 @@ int textclient_startf (textclient_t *a, char const *const *argv, char const *const *envp, uint32_t options, char const *before, size_t beforelen, char const *after, size_t afterlen, tain_t const *deadline, tain_t *stamp) { struct iovec v ; - int fd[3] ; - pid_t pid = child_spawn(argv[0], argv, envp, fd, 3) ; + int fd[3] = { 0, 1 } ; + pid_t pid = child_spawn3(argv[0], argv, envp, fd) ; if (!pid) return 0 ; textmessage_receiver_init(&a->syncin, fd[0], a->syncbuf, TEXTCLIENT_BUFSIZE, TEXTMESSAGE_MAXLEN) ; textmessage_receiver_init(&a->asyncin, fd[2], a->asyncbuf, TEXTCLIENT_BUFSIZE, TEXTMESSAGE_MAXLEN) ; |