summaryrefslogtreecommitdiff
path: root/src/libstddjb/child_spawn.c
diff options
context:
space:
mode:
authorLaurent Bercot <ska-skaware@skarnet.org>2023-09-09 03:55:38 +0000
committerLaurent Bercot <ska@appnovation.com>2023-09-09 03:55:38 +0000
commit4cce87557feb6933c284d234c448bd8bde4facae (patch)
tree7417e8558b0770da2ae24df8abd755dbc913855f /src/libstddjb/child_spawn.c
parenta646c96d5f7ec4b4e0bb538a41fc202c2cdb3309 (diff)
downloadskalibs-4cce87557feb6933c284d234c448bd8bde4facae.tar.xz
cspawn revamp, part 1. Prepare for 2.14.0.0.
Signed-off-by: Laurent Bercot <ska@appnovation.com>
Diffstat (limited to 'src/libstddjb/child_spawn.c')
-rw-r--r--src/libstddjb/child_spawn.c198
1 files changed, 22 insertions, 176 deletions
diff --git a/src/libstddjb/child_spawn.c b/src/libstddjb/child_spawn.c
index 7c59fba..fb5be27 100644
--- a/src/libstddjb/child_spawn.c
+++ b/src/libstddjb/child_spawn.c
@@ -1,208 +1,56 @@
/* ISC license. */
-/* MT-unsafe */
-
-#include <skalibs/sysdeps.h>
-
#include <string.h>
-#include <errno.h>
#include <unistd.h>
#include <skalibs/types.h>
#include <skalibs/djbunix.h>
-
-#ifdef SKALIBS_HASPOSIXSPAWN
-
-#include <signal.h>
-#include <stdlib.h>
-#include <spawn.h>
-
-#include <skalibs/config.h>
#include <skalibs/env.h>
+#include <skalibs/cspawn.h>
-pid_t child_spawn (char const *prog, char const *const *argv, char const *const *envp, int *fds, unsigned int n)
+pid_t child_spawn (char const *prog, char const *const *argv, char const *const *envp, int *fds, size_t n)
{
pid_t pid ;
- posix_spawn_file_actions_t actions ;
- posix_spawnattr_t attr ;
- sigset_t set ;
- int e ;
- int p[n ? n : 1][2] ;
+ cspawn_fileaction fa[2] =
+ {
+ [0] = { .type = CSPAWN_FA_MOVE, .x = { .fd2 = { [0] = 1 } } },
+ [1] = { .type = CSPAWN_FA_MOVE, .x = { .fd2 = { [0] = 0 } } }
+ } ;
size_t m = sizeof(SKALIBS_CHILD_SPAWN_FDS_ENVVAR) ;
- unsigned int i = 0 ;
+ size_t envlen = env_len(envp) ;
+ size_t i = 0 ;
+ int p[n ? n : 1][2] ;
+ char const *newenv[envlen + 2] ;
char modifs[m + 1 + n * UINT_FMT] ;
-#ifdef SKALIBS_HASPOSIXSPAWNEARLYRETURN
- int syncpipe[2] ;
- if (pipecoe(syncpipe) == -1) return 0 ;
-#endif
- memcpy(modifs, SKALIBS_CHILD_SPAWN_FDS_ENVVAR "=", sizeof(SKALIBS_CHILD_SPAWN_FDS_ENVVAR)) ;
for (; i < n ; i++)
{
if (pipe(p[i]) == -1) goto errpi ;
- if ((ndelay_on(p[i][i & 1]) == -1) || (coe(p[i][i & 1]) == -1))
- {
- i++ ; goto errpi ;
- }
- }
- for (i = 2 ; i < n ; i++)
- {
- m += uint_fmt(modifs + m, p[i][!(i & 1)]) ;
- if (i+1 < n) modifs[m++] = ',' ;
- }
- modifs[m++] = 0 ;
-
- e = posix_spawnattr_init(&attr) ;
- if (e) goto erre ;
- 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 ;
- if (n >= 2 && p[1][0])
- {
- e = posix_spawn_file_actions_adddup2(&actions, p[1][0], 0) ;
- if (e) goto erractions ;
- e = posix_spawn_file_actions_addclose(&actions, p[1][0]) ;
- if (e) goto erractions ;
- }
- if (n && p[0][1] != 1)
- {
- e = posix_spawn_file_actions_adddup2(&actions, p[0][1], 1) ;
- if (e) goto erractions ;
- e = posix_spawn_file_actions_addclose(&actions, p[0][1]) ;
- if (e) goto erractions ;
- }
- {
- int nopath = !getenv("PATH") ;
- size_t envlen = env_len(envp) ;
- char const *newenv[envlen + 2] ;
- if (!env_mergen(newenv, envlen+2, envp, envlen, modifs, m, 1)) goto erractions ;
- if (nopath && (setenv("PATH", SKALIBS_DEFAULTPATH, 0) < 0))
- {
- e = errno ; goto erractions ;
- }
- e = posix_spawnp(&pid, prog, &actions, &attr, (char *const *)argv, (char *const *)newenv) ;
- if (nopath) unsetenv("PATH") ;
- if (e) goto erractions ;
- }
-
- posix_spawn_file_actions_destroy(&actions) ;
- posix_spawnattr_destroy(&attr) ;
- for (i = 0 ; i < n ; i++) fd_close(p[i][!(i & 1)]) ;
-
-#ifdef SKALIBS_HASPOSIXSPAWNEARLYRETURN
- pid = child_spawn_workaround(pid, syncpipe) ;
- if (!pid)
- {
- for (i = 0 ; i < n ; i++) fd_close(p[i][i & 1]) ;
- return 0 ;
- }
-#endif
- for (i = 0 ; i < n ; i++) fds[i] = p[i][i & 1] ;
- return pid ;
-
- erractions:
- posix_spawn_file_actions_destroy(&actions) ;
- errattr:
- posix_spawnattr_destroy(&attr) ;
- erre:
- errno = e ;
- i = n ;
- errpi:
- while (i--)
- {
- fd_close(p[i][1]) ;
- fd_close(p[i][0]) ;
+ if ((ndelay_on(p[i][i & 1]) == -1) || (coe(p[i][i & 1]) == -1)) goto errpip ;
}
-#ifdef SKALIBS_HASPOSIXSPAWNEARLYRETURN
- fd_close(syncpipe[1]) ;
- fd_close(syncpipe[0]) ;
-#endif
- return 0 ;
-}
-
-#else
-
-#include <skalibs/allreadwrite.h>
-#include <skalibs/sig.h>
-#include <skalibs/exec.h>
-
-pid_t child_spawn (char const *prog, char const *const *argv, char const *const *envp, int *fds, unsigned int n)
-{
- pid_t pid ;
- int syncpipe[2] ;
- int p[n ? n : 1][2] ;
- size_t m = sizeof(SKALIBS_CHILD_SPAWN_FDS_ENVVAR) ;
- unsigned int i = 0 ;
- char modifs[m + 1 + n * UINT_FMT] ;
- char c ;
memcpy(modifs, SKALIBS_CHILD_SPAWN_FDS_ENVVAR "=", sizeof(SKALIBS_CHILD_SPAWN_FDS_ENVVAR)) ;
- for (; i < n ; i++)
- {
- if (pipe(p[i]) == -1) goto errpi ;
- if ((ndelay_on(p[i][i & 1]) == -1) || (coe(p[i][i & 1]) == -1))
- {
- i++ ; goto errpi ;
- }
- }
for (i = 2 ; i < n ; i++)
{
m += uint_fmt(modifs + m, p[i][!(i & 1)]) ;
if (i+1 < n) modifs[m++] = ',' ;
}
modifs[m++] = 0 ;
+ if (!env_mergen(newenv, envlen + 2, envp, envlen, modifs, m, 1)) goto errpi ;
+ if (n) fa[0].x.fd2[1] = p[0][1] ;
+ if (n >= 2) fa[1].x.fd2[1] = p[1][0] ;
+ pid = cspawn(prog, argv, newenv, CSPAWN_FLAGS_SIGBLOCKNONE, fa, n < 2 ? n : 2) ;
+ if (!pid) goto errpi ;
- if (pipecoe(syncpipe) < 0) goto errp ;
-
- pid = fork() ;
- if (pid < 0) goto errsp ;
- else if (!pid)
+ for (i = 0 ; i < n ; i++)
{
- if (n >= 2)
- {
- if (fd_move2(0, p[1][0], 1, p[0][1]) == -1) goto syncdie ;
- }
- else if (n)
- {
- if (fd_move(1, p[0][1]) == -1) goto syncdie ;
- }
- sig_blocknone() ;
- mexec_aen(prog, argv, envp, modifs, m, 1) ;
- syncdie:
- c = errno ;
- fd_write(syncpipe[1], &c, 1) ;
- _exit(127) ;
- }
-
- fd_close(syncpipe[1]) ;
- syncpipe[1] = fd_read(syncpipe[0], &c, 1) ;
- if (syncpipe[1])
- {
- int e = (unsigned char)c ;
- if (syncpipe[1] == -1) e = errno ;
- if (wait_pid(pid, 0) == -1) e = errno ;
- errno = e ;
- goto errsp0 ;
- }
- fd_close(syncpipe[0]) ;
-
- for (i = n ; i ; i--)
- {
- fd_close(p[i-1][i & 1]) ;
- fds[i-1] = p[i-1][!(i & 1)] ;
+ fd_close(p[i][!(i & 1)]) ;
+ fds[i] = p[i][i & 1] ;
}
return pid ;
- errsp:
- fd_close(syncpipe[1]) ;
- errsp0:
- fd_close(syncpipe[0]) ;
- errp:
- i = n ;
+ errpip:
+ i++ ;
errpi:
while (i--)
{
@@ -211,5 +59,3 @@ pid_t child_spawn (char const *prog, char const *const *argv, char const *const
}
return 0 ;
}
-
-#endif