From 252e2ad869637ca3ef8690854a8fac784b869ec9 Mon Sep 17 00:00:00 2001 From: Laurent Bercot Date: Sun, 10 Sep 2023 04:59:41 +0000 Subject: Add POSIX_SPAWN_SETSID support to cspawn Signed-off-by: Laurent Bercot --- src/include/skalibs/cspawn.h | 1 + src/libstddjb/cspawn.c | 168 ++++++++++++++++++++++---------------- src/sysdeps/tryposixspawnsetsid.c | 30 +++++++ 3 files changed, 128 insertions(+), 71 deletions(-) create mode 100644 src/sysdeps/tryposixspawnsetsid.c (limited to 'src') diff --git a/src/include/skalibs/cspawn.h b/src/include/skalibs/cspawn.h index f76fa62..01f6570 100644 --- a/src/include/skalibs/cspawn.h +++ b/src/include/skalibs/cspawn.h @@ -8,6 +8,7 @@ #define CSPAWN_FLAGS_SELFPIPE_FINISH 0x0001U #define CSPAWN_FLAGS_SIGBLOCKNONE 0x0002U +#define CSPAWN_FLAGS_SETSID 0x0004U #define CSPAWN_FA_CLOSE 0x0000U #define CSPAWN_FA_COPY 0x0001U diff --git a/src/libstddjb/cspawn.c b/src/libstddjb/cspawn.c index 4db86e0..a4c0497 100644 --- a/src/libstddjb/cspawn.c +++ b/src/libstddjb/cspawn.c @@ -2,10 +2,93 @@ #include +#ifdef SKALIBS_HASPOSIXSPAWN +#include +#endif + #include +#include +#include + +#include +#include +#include +#include +#include #include +static inline void cspawn_child_exec (char const *prog, char const *const *argv, char const *const *envp, uint32_t flags, cspawn_fileaction const *fa, size_t n) +{ + for (size_t i = 0 ; i < n ; i++) + { + switch (fa[i].type) + { + case CSPAWN_FA_CLOSE : fd_close(fa[i].x.fd) ; break ; + case CSPAWN_FA_COPY : + if (fd_copy(fa[i].x.fd2[0], fa[i].x.fd2[1]) == -1) return ; + break ; + case CSPAWN_FA_MOVE : + if (fd_move(fa[i].x.fd2[0], fa[i].x.fd2[1]) == -1) return ; + break ; + case CSPAWN_FA_OPEN : + { + int fd = open(fa[i].x.openinfo.file, fa[i].x.openinfo.oflag, fa[i].x.openinfo.mode) ; + if (fd == -1) return ; + if (fd_move(fa[i].x.openinfo.fd, fd) == -1) return ; + break ; + } + default : + errno = EINVAL ; return ; + } + } + + if (flags & CSPAWN_FLAGS_SELFPIPE_FINISH) selfpipe_finish() ; + if (flags & CSPAWN_FLAGS_SIGBLOCKNONE) sig_blocknone() ; + if (flags & CSPAWN_FLAGS_SETSID) setsid() ; + + exec_ae(prog, argv, envp) ; +} + +static inline pid_t cspawn_fork (char const *prog, char const *const *argv, char const *const *envp, uint32_t flags, cspawn_fileaction const *fa, size_t n) +{ + pid_t pid ; + int p[2] ; + char c ; + + if (pipecoe(p) == -1) return 0 ; + pid = fork() ; + if (pid == -1) + { + fd_close(p[1]) ; + fd_close(p[0]) ; + return 0 ; + } + if (!pid) + { + cspawn_child_exec(prog, argv, envp, flags, fa, n) ; + c = errno ; + fd_write(p[1], &c, 1) ; + _exit(127) ; + } + + fd_close(p[1]) ; + p[1] = fd_read(p[0], &c, 1) ; + if (p[1] < 0) + { + fd_close(p[0]) ; + return 0 ; + } + fd_close(p[0]) ; + if (p[1]) + { + wait_pid(pid, &p[0]) ; + errno = (unsigned char)c ; + return 0 ; + } + return pid ; +} + #ifdef SKALIBS_HASPOSIXSPAWN #include @@ -19,8 +102,6 @@ #include -#include - static inline pid_t cspawn_workaround (pid_t pid, int const *p) { siginfo_t si ; @@ -50,7 +131,7 @@ static inline pid_t cspawn_workaround (pid_t pid, int const *p) #endif -pid_t cspawn (char const *prog, char const *const *argv, char const *const *envp, uint32_t flags, cspawn_fileaction const *fa, size_t n) +static inline pid_t cspawn_pspawn (char const *prog, char const *const *argv, char const *const *envp, uint32_t flags, cspawn_fileaction const *fa, size_t n) { pid_t pid ; posix_spawnattr_t attr ; @@ -139,82 +220,27 @@ pid_t cspawn (char const *prog, char const *const *argv, char const *const *envp return 0 ; } -#else - -#include -#include - -#include -#include -#include -#include +#ifdef SKALIBS_HASPOSIXSPAWNSETSID -static inline void cspawn_child_exec (char const *prog, char const *const *argv, char const *const *envp, uint32_t flags, cspawn_fileaction const *fa, size_t n) +pid_t cspawn (char const *prog, char const *const *argv, char const *const *envp, uint32_t flags, cspawn_fileaction const *fa, size_t n) { - for (size_t i = 0 ; i < n ; i++) - { - switch (fa[i].type) - { - case CSPAWN_FA_CLOSE : fd_close(fa[i].x.fd) ; break ; - case CSPAWN_FA_COPY : - if (fd_copy(fa[i].x.fd2[0], fa[i].x.fd2[1]) == -1) return ; - break ; - case CSPAWN_FA_MOVE : - if (fd_move(fa[i].x.fd2[0], fa[i].x.fd2[1]) == -1) return ; - break ; - case CSPAWN_FA_OPEN : - { - int fd = open(fa[i].x.openinfo.file, fa[i].x.openinfo.oflag, fa[i].x.openinfo.mode) ; - if (fd == -1) return ; - if (fd_move(fa[i].x.openinfo.fd, fd) == -1) return ; - break ; - } - default : - errno = EINVAL ; return ; - } - } - - if (flags & CSPAWN_FLAGS_SELFPIPE_FINISH) selfpipe_finish() ; - if (flags & CSPAWN_FLAGS_SIGBLOCKNONE) sig_blocknone() ; + return cspawn_pspawn(prog, argv, envp, flags, fa, n) ; } +#else + pid_t cspawn (char const *prog, char const *const *argv, char const *const *envp, uint32_t flags, cspawn_fileaction const *fa, size_t n) { - pid_t pid ; - int p[2] ; - char c ; + return flags & CSPAWN_FLAGS_SETSID ? cspawn_fork(prog, argv, envp, flags, fa, n) : cspawn_pspawn(prog, argv, envp, flags, fa, n) ; +} - if (pipecoe(p) == -1) return 0 ; - pid = fork() ; - if (pid == -1) - { - fd_close(p[1]) ; - fd_close(p[0]) ; - return 0 ; - } - if (!pid) - { - cspawn_child_exec(prog, argv, envp, flags, fa, n) ; - c = errno ; - fd_write(p[1], &c, 1) ; - _exit(127) ; - } +#endif - fd_close(p[1]) ; - p[1] = fd_read(p[0], &c, 1) ; - if (p[1] < 0) - { - fd_close(p[0]) ; - return 0 ; - } - fd_close(p[0]) ; - if (p[1]) - { - wait_pid(pid, &p[0]) ; - errno = (unsigned char)c ; - return 0 ; - } - return pid ; +#else + +pid_t cspawn (char const *prog, char const *const *argv, char const *const *envp, uint32_t flags, cspawn_fileaction const *fa, size_t n) +{ + return cspawn_fork(prog, argv, envp, flags, fa, n) ; } #endif diff --git a/src/sysdeps/tryposixspawnsetsid.c b/src/sysdeps/tryposixspawnsetsid.c new file mode 100644 index 0000000..10e4e2e --- /dev/null +++ b/src/sysdeps/tryposixspawnsetsid.c @@ -0,0 +1,30 @@ +/* ISC license. */ + +#undef _POSIX_C_SOURCE +#undef _XOPEN_SOURCE + +#ifndef _XPG4_2 +#define _XPG4_2 +#endif + +#ifndef _GNU_SOURCE +#define _GNU_SOURCE +#endif + +#ifndef _DEFAULT_SOURCE +#define _DEFAULT_SOURCE +#endif + +#include + +int main (void) +{ + pid_t pid ; + posix_spawn_file_actions_t actions ; + posix_spawnattr_t attr ; + char *const argv[2] = { "/bin/true", 0 } ; + char *const envp[1] = { 0 } ; + posix_spawnattr_setflags(&attr, POSIX_SPAWN_SETSID) ; + posix_spawn_file_actions_init(&actions) ; + return posix_spawn(&pid, argv[0], 0, 0, argv, envp) ; +} -- cgit v1.2.3