commit d16e2baf35963f6ed2ccd23a3aa3df69cd65dd84
parent 08997ab1211eb3ee52feeb7bd9062da2f168f834
Author: Laurent Bercot <ska-skaware@skarnet.org>
Date: Wed, 19 Oct 2016 01:01:38 +0000
Add child_spawn2
Diffstat:
3 files changed, 162 insertions(+), 1 deletion(-)
diff --git a/package/deps.mak b/package/deps.mak
@@ -130,7 +130,7 @@ src/libdatastruct/gensetdyn_ready.o src/libdatastruct/gensetdyn_ready.lo: src/li
src/libdatastruct/gensetdyn_zero.o src/libdatastruct/gensetdyn_zero.lo: src/libdatastruct/gensetdyn_zero.c src/include/skalibs/gensetdyn.h
src/librandom/random_char.o src/librandom/random_char.lo: src/librandom/random_char.c src/include/skalibs/random.h
src/librandom/random_finish.o src/librandom/random_finish.lo: src/librandom/random_finish.c src/include/skalibs/djbunix.h src/librandom/random-internal.h src/include/skalibs/random.h src/include/skalibs/sysdeps.h
-src/librandom/random_init.o src/librandom/random_init.lo: src/librandom/random_init.c src/include/skalibs/djbunix.h src/include/skalibs/nonposix.h src/librandom/random-internal.h src/include/skalibs/random.h src/include/skalibs/sysdeps.h
+src/librandom/random_init.o src/librandom/random_init.lo: src/librandom/random_init.c src/include/skalibs/djbunix.h src/include/skalibs/nonposix.h src/librandom/random-internal.h src/include/skalibs/random.h src/include/skalibs/surf.h src/include/skalibs/sysdeps.h
src/librandom/random_makeseed.o src/librandom/random_makeseed.lo: src/librandom/random_makeseed.c src/include/skalibs/sha1.h src/include/skalibs/tai.h src/include/skalibs/uint32.h
src/librandom/random_name.o src/librandom/random_name.lo: src/librandom/random_name.c src/include/skalibs/random.h
src/librandom/random_sauniquename.o src/librandom/random_sauniquename.lo: src/librandom/random_sauniquename.c src/include/skalibs/random.h src/include/skalibs/skamisc.h src/include/skalibs/stralloc.h
@@ -264,6 +264,7 @@ src/libstddjb/child_spawn0.o src/libstddjb/child_spawn0.lo: src/libstddjb/child_
src/libstddjb/child_spawn1_internal.o src/libstddjb/child_spawn1_internal.lo: src/libstddjb/child_spawn1_internal.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/sysdeps.h
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/bytestr.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/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
@@ -158,6 +158,15 @@ extern pid_t child_spawn1_socket (char const *, char const *const *, char const
/*
+ Spawn function with 2 communicating pipes. The int * points to 2 fds.
+ Input: fds[0] and fds[1] are the fds to move the pipes to in the child.
+ Output: fds[0] and fds[1] contain the pipes to the child.
+ */
+
+extern pid_t child_spawn2 (char const *, char const *const *, char const *const *, int *) ;
+
+
+ /*
Unified function to fork a child with communication canals.
* uses posix_spawn() if available, else uses fork+exec
* requests n (the last arg) communication fds between parent and child
diff --git a/src/libstddjb/child_spawn2.c b/src/libstddjb/child_spawn2.c
@@ -0,0 +1,151 @@
+/* ISC license. */
+
+/* MT-unsafe */
+
+#include <skalibs/sysdeps.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <sys/wait.h>
+#include <unistd.h>
+#include <errno.h>
+#include <signal.h>
+#include <skalibs/djbunix.h>
+
+#ifdef SKALIBS_HASPOSIXSPAWN
+
+#include <stdlib.h>
+#include <spawn.h>
+#include <skalibs/config.h>
+#include <skalibs/env.h>
+
+#else
+
+#include <skalibs/bytestr.h>
+#include <skalibs/allreadwrite.h>
+#include <skalibs/sig.h>
+#include <skalibs/strerr2.h>
+
+#endif
+
+pid_t child_spawn2 (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[2][2] ;
+ pid_t pid ;
+ int e ;
+ if (pipe(p[0]) < 0) return 0 ;
+ if (ndelay_on(p[0][0]) < 0 || coe(p[0][0]) < 0 || pipe(p[1]) < 0) { e = errno ; goto errp ; }
+ if (ndelay_on(p[1][1]) < 0 || coe(p[1][1]) < 0) { e = errno ; goto errsp ; }
+
+#ifdef SKALIBS_HASPOSIXSPAWN
+
+ e = posix_spawnattr_init(&attr) ;
+ if (e) goto errsp ;
+ {
+ 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 = !!env_get("PATH") ;
+ if (!haspath && (setenv("PATH", SKALIBS_DEFAULTPATH, 0) < 0))
+ {
+ e = errno ; goto erractions ;
+ }
+ e = posix_spawnp(&pid, prog, &actions, &attr, (char *const *)argv, (char *const *)envp) ;
+ 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 errp1 ; }
+ if (coe(syncpipe[1]) < 0) { e = errno ; goto errsp ; }
+
+ pid = fork() ;
+ if (pid < 0) { e = errno ; goto errsp ; }
+ else if (!pid)
+ {
+ unsigned int len = str_len(PROG) ;
+ char name[len + 9] ;
+ byte_copy(name, len, PROG) ;
+ byte_copy(name + len, 9, " (child)") ;
+ 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_run(prog, argv, envp) ;
+
+ syncdie:
+ {
+ unsigned char c = errno ;
+ fd_write(syncpipe[1], (char const *)&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[0][1]) ; fds[0] = p[0][0] ;
+ fd_close(p[1][0]) ; fds[1] = p[1][1] ;
+ return pid ;
+
+#ifdef SKALIBS_HASPOSIXSPAWN
+ erractions:
+ posix_spawn_file_actions_destroy(&actions) ;
+ errattr:
+ posix_spawnattr_destroy(&attr) ;
+#endif
+ errsp:
+#ifndef SKALIBS_HASPOSIXSPAWN
+ fd_close(syncpipe[1]) ;
+ errsp0:
+ fd_close(syncpipe[0]) ;
+ errp1:
+#endif
+ fd_close(p[1][1]) ;
+ fd_close(p[1][0]) ;
+ errp:
+ fd_close(p[0][1]) ;
+ fd_close(p[0][0]) ;
+ errno = e ;
+ return 0 ;
+}
