[PATCH 1/1] posix: Add POSIX aliases to some spawn functions
Adhemerval Zanella Netto
adhemerval.zanella@linaro.org
Tue Mar 31 20:00:29 GMT 2026
On 30/03/26 05:18, Lucas Chollet wrote:
> Both `posix_spawn_file_actions_add{,f}chdir` functions are now fully
> defined by POSIX-2024, this patch adds both functions as aliases of the
> already existing `posix_spawn_file_actions_add{,f}chdir_np` GNU
> extensions.
>
> This makes glibc more compliant in regards to POSIX-2024.
>
> Signed-off-by: Lucas Chollet <lucas.chollet@free.fr>
Hi Lucas,
Thanks for working on this, however you patch has triggered a CI failure [1]
because you only updated the x86_64 abilist (the redhad CI bot runs for
i686-linux-gnu target)
I recall that Florian has added a script to automatically update this, but
I am not sure which is it. In any case, since this is a new symbol for
all ABI with the same version I think you can update all the abilist files
with the following command:
find sysdeps -name 'libc.abilist' -exec sh -c '
echo "GLIBC_2.44 posix_spawn_file_actions_addchdir F" >> "$1"
LC_ALL=C sort -o "$1" "$1"
' _ {} \;
Another options would to bootstrap a compiler using build-many-glibcs.py for
each abilist file, but it is more time consuming.
However we don't really need new symbols, it can use asm alias instead:
extern int __REDIRECT_NTH (posix_spawn_file_actions_addchdir,
(posix_spawn_file_actions_t * __restrict __actions,
const char *__restrict __path),
posix_spawn_file_actions_addchdir_np);
extern int __REDIRECT_NTH (posix_spawn_file_actions_addfchdir,
(posix_spawn_file_actions_t *, int __fd),
posix_spawn_file_actions_addfchdir_np);
[1] https://patchwork.sourceware.org/project/glibc/patch/20260330081840.878377-2-lucas.chollet@free.fr/
> ---
> conform/data/spawn.h-data | 4 +
> posix/Versions | 4 +
> posix/spawn.h | 20 ++
> posix/spawn_faction_addchdir.c | 3 +
> posix/spawn_faction_addfchdir.c | 3 +
> posix/tst-spawn-chdir.c | 222 ++++++++++--------
> .../unix/sysv/linux/x86_64/64/libc.abilist | 2 +
> 7 files changed, 154 insertions(+), 104 deletions(-)
>
> diff --git a/conform/data/spawn.h-data b/conform/data/spawn.h-data
> index 43aa9cb8ae..1f332324c2 100644
> --- a/conform/data/spawn.h-data
> +++ b/conform/data/spawn.h-data
> @@ -29,6 +29,10 @@ function int posix_spawnattr_setpgroup (posix_spawnattr_t*, pid_t)
> function int posix_spawnattr_setschedparam (posix_spawnattr_t*, const struct sched_param*)
> function int posix_spawnattr_setschedpolicy (posix_spawnattr_t*, int)
> function int posix_spawnattr_setsigmask (posix_spawnattr_t*, const sigset_t*)
> +#if defined XOPEN2K24 || defined POSIX2024
> +function int posix_spawn_file_actions_addchdir (posix_spawn_file_actions_t*, const char *)
> +function int posix_spawn_file_actions_addfchdir (posix_spawn_file_actions_t*, int)
> +#endif
> function int posix_spawn_file_actions_addclose (posix_spawn_file_actions_t*, int)
> function int posix_spawn_file_actions_adddup2 (posix_spawn_file_actions_t*, int, int)
> function int posix_spawn_file_actions_addopen (posix_spawn_file_actions_t*, int, const char *, int, mode_t)
> diff --git a/posix/Versions b/posix/Versions
> index 0624d24bcc..3c15dbb50c 100644
> --- a/posix/Versions
> +++ b/posix/Versions
> @@ -159,6 +159,10 @@ libc {
> GLIBC_2.35 {
> posix_spawn_file_actions_addtcsetpgrp_np;
> }
> + GLIBC_2.44 {
> + posix_spawn_file_actions_addchdir;
> + posix_spawn_file_actions_addfchdir;
> + }
> GLIBC_PRIVATE {
> __libc_fork; __libc_pread; __libc_pwrite;
> __nanosleep_nocancel; __pause_nocancel;
> diff --git a/posix/spawn.h b/posix/spawn.h
> index 5e68752a66..1fc300ed13 100644
> --- a/posix/spawn.h
> +++ b/posix/spawn.h
> @@ -200,6 +200,26 @@ extern int posix_spawn_file_actions_adddup2 (posix_spawn_file_actions_t *
> int __fd, int __newfd)
> __THROW __nonnull ((1));
>
> +#ifdef __USE_XOPEN2K24XSI
> +
> +/* Add an action changing the directory to PATH during spawn. This
> + affects the subsequent file actions.
> + Alias of posix_spawn_file_actions_addchdir_np. */
> +extern int posix_spawn_file_actions_addchdir (posix_spawn_file_actions_t *
> + __restrict __actions,
> + const char *__restrict __path)
> + __THROW __nonnull ((1, 2));
> +
> +/* Add an action changing the directory to FD during spawn. This
> + affects the subsequent file actions. FD is not duplicated and must
> + be open when the file action is executed.
> + Alias of posix_spawn_file_actions_addfchdir_np. */
> +extern int posix_spawn_file_actions_addfchdir (posix_spawn_file_actions_t *,
> + int __fd)
> + __THROW __nonnull ((1));
> +
> +#endif /* __USE_XOPEN2K24XSI */
> +
> #ifdef __USE_MISC
> /* Add an action changing the directory to PATH during spawn. This
> affects the subsequent file actions. */
> diff --git a/posix/spawn_faction_addchdir.c b/posix/spawn_faction_addchdir.c
> index 02f8ce27ee..dadb8a27e0 100644
> --- a/posix/spawn_faction_addchdir.c
> +++ b/posix/spawn_faction_addchdir.c
> @@ -51,3 +51,6 @@ posix_spawn_file_actions_addchdir_np (posix_spawn_file_actions_t *file_actions,
>
> return 0;
> }
> +
> +strong_alias (posix_spawn_file_actions_addchdir_np,
> + posix_spawn_file_actions_addchdir)
> diff --git a/posix/spawn_faction_addfchdir.c b/posix/spawn_faction_addfchdir.c
> index a3df6df489..7056993d62 100644
> --- a/posix/spawn_faction_addfchdir.c
> +++ b/posix/spawn_faction_addfchdir.c
> @@ -44,3 +44,6 @@ posix_spawn_file_actions_addfchdir_np (posix_spawn_file_actions_t *actions,
>
> return 0;
> }
> +
> +strong_alias (posix_spawn_file_actions_addfchdir_np,
> + posix_spawn_file_actions_addfchdir)
> diff --git a/posix/tst-spawn-chdir.c b/posix/tst-spawn-chdir.c
> index a3478d61f6..c85465c973 100644
> --- a/posix/tst-spawn-chdir.c
> +++ b/posix/tst-spawn-chdir.c
> @@ -72,18 +72,31 @@ get_pwd_program (void)
> the open function and TMPFD to emulate chdir using fchdir. */
> static void
> add_chdir (posix_spawn_file_actions_t *actions, const char *path,
> - bool do_fchdir, int tmpfd)
> + bool do_fchdir, bool do_posix, int tmpfd)
> {
> if (do_fchdir)
> {
> TEST_COMPARE (posix_spawn_file_actions_addopen
> (actions, tmpfd, path, O_DIRECTORY | O_RDONLY, 0), 0);
> - TEST_COMPARE (posix_spawn_file_actions_addfchdir_np
> - (actions, tmpfd), 0);
> + if (do_posix)
> + {
> + TEST_COMPARE (posix_spawn_file_actions_addfchdir
> + (actions, tmpfd), 0);
> + }
> + else
> + {
> + TEST_COMPARE (posix_spawn_file_actions_addfchdir_np
> + (actions, tmpfd), 0);
> + }
> TEST_COMPARE (posix_spawn_file_actions_addclose (actions, tmpfd), 0);
> }
> else
> - TEST_COMPARE (posix_spawn_file_actions_addchdir_np (actions, path), 0);
> + {
> + if (do_posix)
> + TEST_COMPARE (posix_spawn_file_actions_addchdir (actions, path), 0);
> + else
> + TEST_COMPARE (posix_spawn_file_actions_addchdir_np (actions, path), 0);
> + }
> }
>
> static int
> @@ -110,109 +123,110 @@ do_test (void)
> for (int do_spawnp = 0; do_spawnp < 2; ++do_spawnp)
> for (int do_overwrite = 0; do_overwrite < 2; ++do_overwrite)
> for (int do_fchdir = 0; do_fchdir < 2; ++do_fchdir)
> - {
> - /* This subtest does not make sense for fchdir. */
> - if (do_overwrite && do_fchdir)
> - continue;
> -
> - ++iteration;
> - if (test_verbose > 0)
> - printf ("info: iteration=%d do_spawnp=%d do_overwrite=%d"
> - " do_fchdir=%d\n",
> - iteration, do_spawnp, do_overwrite, do_fchdir);
> -
> - /* The "pwd" program runs in this directory. */
> - char *iteration_directory = xasprintf ("%s/%d", directory, iteration);
> - add_temp_file (iteration_directory);
> - xmkdir (iteration_directory, 0777);
> -
> - /* This file receives output from "pwd". */
> - char *output_file_path
> - = xasprintf ("%s/output-file", iteration_directory);
> - add_temp_file (output_file_path);
> -
> - /* This subdirectory is used for chdir ordering checks. */
> - char *subdir_path = xasprintf ("%s/subdir", iteration_directory);
> - add_temp_file (subdir_path);
> - xmkdir (subdir_path, 0777);
> -
> - /* Also used for checking the order of actions. */
> - char *probe_file_path
> - = xasprintf ("%s/subdir/probe-file", iteration_directory);
> - add_temp_file (probe_file_path);
> - TEST_COMPARE (access (probe_file_path, F_OK), -1);
> - TEST_COMPARE (errno, ENOENT);
> -
> - /* This symbolic link is used in a relative path with
> - posix_spawn. */
> - char *pwd_symlink_path
> - = xasprintf ("%s/subdir/pwd-symlink", iteration_directory);
> - xsymlink (get_pwd_program (), pwd_symlink_path);
> - add_temp_file (pwd_symlink_path);
> -
> - posix_spawn_file_actions_t actions;
> - TEST_COMPARE (posix_spawn_file_actions_init (&actions), 0);
> - add_chdir (&actions, subdir_path, do_fchdir, 4);
> - TEST_COMPARE (posix_spawn_file_actions_addopen
> - (&actions, 3, /* Arbitrary unused descriptor. */
> - "probe-file",
> - O_WRONLY | O_CREAT | O_EXCL, 0666), 0);
> - TEST_COMPARE (posix_spawn_file_actions_addclose (&actions, 3), 0);
> - /* Run the actual in iteration_directory. */
> - add_chdir (&actions, "..", do_fchdir, 5);
> - TEST_COMPARE (posix_spawn_file_actions_addopen
> - (&actions, STDOUT_FILENO, "output-file",
> - O_WRONLY | O_CREAT | O_EXCL, 0666), 0);
> -
> - /* Check that posix_spawn_file_actions_addchdir_np made a copy
> - of the path. */
> - if (do_overwrite)
> - subdir_path[0] = '\0';
> -
> - char *const argv[] = { (char *) "pwd", NULL };
> - char *const envp[] = { NULL } ;
> - PID_T_TYPE pid;
> - if (do_spawnp)
> - TEST_COMPARE (POSIX_SPAWNP (&pid, "pwd", &actions,
> - NULL, argv, envp), 0);
> - else
> - TEST_COMPARE (POSIX_SPAWN (&pid, "subdir/pwd-symlink", &actions,
> - NULL, argv, envp), 0);
> - TEST_VERIFY (pid > 0);
> - siginfo_t sinfo;
> - TEST_COMPARE (WAITID (P_ALL, 0, &sinfo, WEXITED), 0);
> - TEST_COMPARE (sinfo.si_code, CLD_EXITED);
> - TEST_COMPARE (sinfo.si_status, 0);
> -
> - /* Check that the current directory did not change. */
> - {
> - char *cwd = get_current_dir_name ();
> - if (cwd == NULL)
> - FAIL_EXIT1 ("get_current_dir_name: %m");
> - TEST_COMPARE_BLOB (original_cwd, strlen (original_cwd),
> - cwd, strlen (cwd));
> - free (cwd);
> - }
> -
> -
> - /* Check the output from "pwd". */
> + for (int do_posix = 0; do_posix < 2; ++do_posix)
> {
> - char *pwd = read_one_line (output_file_path);
> - TEST_COMPARE_BLOB (iteration_directory, strlen (iteration_directory),
> - pwd, strlen (pwd));
> - free (pwd);
> + /* This subtest does not make sense for fchdir. */
> + if (do_overwrite && do_fchdir)
> + continue;
> +
> + ++iteration;
> + if (test_verbose > 0)
> + printf ("info: iteration=%d do_spawnp=%d do_overwrite=%d"
> + " do_fchdir=%d do_posix=%d\n",
> + iteration, do_spawnp, do_overwrite, do_fchdir, do_posix);
> +
> + /* The "pwd" program runs in this directory. */
> + char *iteration_directory = xasprintf ("%s/%d", directory, iteration);
> + add_temp_file (iteration_directory);
> + xmkdir (iteration_directory, 0777);
> +
> + /* This file receives output from "pwd". */
> + char *output_file_path
> + = xasprintf ("%s/output-file", iteration_directory);
> + add_temp_file (output_file_path);
> +
> + /* This subdirectory is used for chdir ordering checks. */
> + char *subdir_path = xasprintf ("%s/subdir", iteration_directory);
> + add_temp_file (subdir_path);
> + xmkdir (subdir_path, 0777);
> +
> + /* Also used for checking the order of actions. */
> + char *probe_file_path
> + = xasprintf ("%s/subdir/probe-file", iteration_directory);
> + add_temp_file (probe_file_path);
> + TEST_COMPARE (access (probe_file_path, F_OK), -1);
> + TEST_COMPARE (errno, ENOENT);
> +
> + /* This symbolic link is used in a relative path with
> + posix_spawn. */
> + char *pwd_symlink_path
> + = xasprintf ("%s/subdir/pwd-symlink", iteration_directory);
> + xsymlink (get_pwd_program (), pwd_symlink_path);
> + add_temp_file (pwd_symlink_path);
> +
> + posix_spawn_file_actions_t actions;
> + TEST_COMPARE (posix_spawn_file_actions_init (&actions), 0);
> + add_chdir (&actions, subdir_path, do_fchdir, do_posix, 4);
> + TEST_COMPARE (posix_spawn_file_actions_addopen
> + (&actions, 3, /* Arbitrary unused descriptor. */
> + "probe-file",
> + O_WRONLY | O_CREAT | O_EXCL, 0666), 0);
> + TEST_COMPARE (posix_spawn_file_actions_addclose (&actions, 3), 0);
> + /* Run the actual in iteration_directory. */
> + add_chdir (&actions, "..", do_fchdir, do_posix, 5);
> + TEST_COMPARE (posix_spawn_file_actions_addopen
> + (&actions, STDOUT_FILENO, "output-file",
> + O_WRONLY | O_CREAT | O_EXCL, 0666), 0);
> +
> + /* Check that posix_spawn_file_actions_addchdir_np made a copy
> + of the path. */
> + if (do_overwrite)
> + subdir_path[0] = '\0';
> +
> + char *const argv[] = { (char *) "pwd", NULL };
> + char *const envp[] = { NULL } ;
> + PID_T_TYPE pid;
> + if (do_spawnp)
> + TEST_COMPARE (POSIX_SPAWNP (&pid, "pwd", &actions,
> + NULL, argv, envp), 0);
> + else
> + TEST_COMPARE (POSIX_SPAWN (&pid, "subdir/pwd-symlink", &actions,
> + NULL, argv, envp), 0);
> + TEST_VERIFY (pid > 0);
> + siginfo_t sinfo;
> + TEST_COMPARE (WAITID (P_ALL, 0, &sinfo, WEXITED), 0);
> + TEST_COMPARE (sinfo.si_code, CLD_EXITED);
> + TEST_COMPARE (sinfo.si_status, 0);
> +
> + /* Check that the current directory did not change. */
> + {
> + char *cwd = get_current_dir_name ();
> + if (cwd == NULL)
> + FAIL_EXIT1 ("get_current_dir_name: %m");
> + TEST_COMPARE_BLOB (original_cwd, strlen (original_cwd),
> + cwd, strlen (cwd));
> + free (cwd);
> + }
> +
> +
> + /* Check the output from "pwd". */
> + {
> + char *pwd = read_one_line (output_file_path);
> + TEST_COMPARE_BLOB (iteration_directory, strlen (iteration_directory),
> + pwd, strlen (pwd));
> + free (pwd);
> + }
> +
> + /* This file must now exist. */
> + TEST_COMPARE (access (probe_file_path, F_OK), 0);
> +
> + TEST_COMPARE (posix_spawn_file_actions_destroy (&actions), 0);
> + free (pwd_symlink_path);
> + free (probe_file_path);
> + free (subdir_path);
> + free (output_file_path);
> }
>
> - /* This file must now exist. */
> - TEST_COMPARE (access (probe_file_path, F_OK), 0);
> -
> - TEST_COMPARE (posix_spawn_file_actions_destroy (&actions), 0);
> - free (pwd_symlink_path);
> - free (probe_file_path);
> - free (subdir_path);
> - free (output_file_path);
> - }
> -
> free (directory);
>
> return 0;
Ok, although I think it would be simpler to add a new test that included this
files and build with _POSIX_C_SOURCE=202405L.
> diff --git a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
> index 306cd627fd..3c42d9526d 100644
> --- a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
> @@ -2771,6 +2771,8 @@ GLIBC_2.43 memset_explicit F
> GLIBC_2.43 mseal F
> GLIBC_2.43 openat2 F
> GLIBC_2.43 umaxabs F
> +GLIBC_2.44 posix_spawn_file_actions_addchdir F
> +GLIBC_2.44 posix_spawn_file_actions_addfchdir F
> GLIBC_2.5 __readlinkat_chk F
> GLIBC_2.5 inet6_opt_append F
> GLIBC_2.5 inet6_opt_find F
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