From 0dcf66744f533e160232072bd03273ca1c448879 Mon Sep 17 00:00:00 2001 From: Ismael Luceno Date: Mon, 5 Mar 2012 06:43:49 -0200 Subject: [PATCH] librt: add posix_spawn support Signed-off-by: Ismael Luceno Signed-off-by: Mike Frysinger --- Makefile.in | 1 + include/spawn.h | 266 +++++++++++++++++++++++++++++++++++++++++ librt/Makefile.in | 8 ++ librt/spawn.c | 259 +++++++++++++++++++++++++++++++++++++++ librt/spawn_faction_addclose.c | 51 ++++++++ librt/spawn_faction_adddup2.c | 52 ++++++++ librt/spawn_faction_addopen.c | 55 +++++++++ librt/spawn_faction_init.c | 42 +++++++ librt/spawn_int.h | 26 ++++ 9 files changed, 760 insertions(+) create mode 100644 include/spawn.h create mode 100644 librt/spawn.c create mode 100644 librt/spawn_faction_addclose.c create mode 100644 librt/spawn_faction_adddup2.c create mode 100644 librt/spawn_faction_addopen.c create mode 100644 librt/spawn_faction_init.c create mode 100644 librt/spawn_int.h diff --git a/Makefile.in b/Makefile.in index d0ac6c0..82a2eff 100644 --- a/Makefile.in +++ b/Makefile.in @@ -290,6 +290,7 @@ HEADERS_RM-$(UCLIBC_SUPPORT_AI_ADDRCONFIG) += ifaddrs.h HEADERS_RM-$(UCLIBC_SV4_DEPRECATED) += ustat.h sys/ustat.h bits/ustat.h HEADERS_RM-$(UCLIBC_SUSV3_LEGACY) += sys/timeb.h regexp.h HEADERS_RM-$(UCLIBC_SUSV4_LEGACY) += utime.h ucontext.h +HEADERS_RM-$(UCLIBC_HAS_ADVANCED_REALTIME) += spawn.h ifneq ($(findstring install,$(MAKECMDGOALS)),) $(addprefix $(PREFIX)$(DEVEL_PREFIX),include $(MULTILIB_DIR)): diff --git a/include/spawn.h b/include/spawn.h new file mode 100644 index 0000000..8b07bb8 --- /dev/null +++ b/include/spawn.h @@ -0,0 +1,266 @@ +/* Definitions for POSIX spawn interface. + Copyright (C) 2000,2003,2004,2009,2011,2012 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#ifndef _SPAWN_H +#define _SPAWN_H 1 + +#include +#include +#include + +#include +#include +#define __need_sigset_t +#include +#include + + +/* Data structure to contain attributes for thread creation. */ +typedef struct { + short int __flags; + pid_t __pgrp; + sigset_t __sd; + sigset_t __ss; + struct sched_param __sp; + int __policy; + int __pad[16]; +} posix_spawnattr_t; + + +/* Data structure to contain information about the actions to be + performed in the new process with respect to file descriptors. */ +typedef struct { + int __allocated; + int __used; + struct __spawn_action *__actions; + int __pad[16]; +} posix_spawn_file_actions_t; + + +/* Flags to be set in the `posix_spawnattr_t'. */ +#define POSIX_SPAWN_RESETIDS 0x01 +#define POSIX_SPAWN_SETPGROUP 0x02 +#define POSIX_SPAWN_SETSIGDEF 0x04 +#define POSIX_SPAWN_SETSIGMASK 0x08 +#define POSIX_SPAWN_SETSCHEDPARAM 0x10 +#define POSIX_SPAWN_SETSCHEDULER 0x20 +#define POSIX_SPAWN_USEVFORK 0x40 /* GNU extension */ + + +#define __POSIX_SPAWN_MASK (POSIX_SPAWN_RESETIDS \ + | POSIX_SPAWN_SETPGROUP \ + | POSIX_SPAWN_SETSIGDEF \ + | POSIX_SPAWN_SETSIGMASK \ + | POSIX_SPAWN_SETSCHEDPARAM \ + | POSIX_SPAWN_SETSCHEDULER \ + | POSIX_SPAWN_USEVFORK) + +__BEGIN_DECLS + +/* Spawn a new process executing PATH with the attributes describes in *ATTRP. + Before running the process perform the actions described in FILE-ACTIONS. + + This function is a possible cancellation point and therefore not + marked with __THROW. */ +int posix_spawn(pid_t * restrict pid, const char * restrict path, + const posix_spawn_file_actions_t * restrict file_actions, + const posix_spawnattr_t * restrict attrp, + char * const argv[restrict], + char * const envp[restrict]); + +/* Similar to `posix_spawn' but search for FILE in the PATH. + + This function is a possible cancellation point and therefore not + marked with __THROW. */ +int posix_spawnp(pid_t *pid, const char *file, + const posix_spawn_file_actions_t *file_actions, + const posix_spawnattr_t *attrp, + char * const argv[], char * const envp[]); + +/* Initialize data structure with attributes for `spawn' to default values. */ +inline static int +posix_spawnattr_init(posix_spawnattr_t *attr) +{ + memset(attr, 0, sizeof(*attr)); + return 0; +} + +/* Free resources associated with ATTR. */ +inline static int +posix_spawnattr_destroy(posix_spawnattr_t *attr) +{ + return 0; +} + +/* Store signal mask for signals with default handling from ATTR in + SIGDEFAULT. */ +inline static int +posix_spawnattr_getsigdefault(const posix_spawnattr_t *attr, + sigset_t *sigdefault) +{ + memcpy(sigdefault, &attr->__sd, sizeof(sigset_t)); + return 0; +} + + +/* Set signal mask for signals with default handling in ATTR to SIGDEFAULT. */ +inline static int +posix_spawnattr_setsigdefault(posix_spawnattr_t *attr, + const sigset_t *sigdefault) +{ + memcpy(&attr->__sd, sigdefault, sizeof(sigset_t)); + return 0; +} + +/* Store signal mask for the new process from ATTR in SIGMASK. */ +inline static int +posix_spawnattr_getsigmask(const posix_spawnattr_t *attr, + sigset_t *sigmask) +{ + memcpy(sigmask, &attr->__ss, sizeof(sigset_t)); + return 0; +} + + +/* Set signal mask for the new process in ATTR to SIGMASK. */ +inline static int +posix_spawnattr_setsigmask(posix_spawnattr_t *attr, + const sigset_t *sigmask) +{ + memcpy(&attr->__ss, sigmask, sizeof(sigset_t)); + return 0; +} + +/* Get flag word from the attribute structure. */ +inline static int +posix_spawnattr_getflags(const posix_spawnattr_t *attr, short int *flags) +{ + *flags = attr->__flags; + return 0; +} + +/* Store flags in the attribute structure. */ +inline static int +posix_spawnattr_setflags(posix_spawnattr_t *attr, short int flags) +{ + /* Check no invalid bits are set. */ + if (flags & ~__POSIX_SPAWN_MASK) + return EINVAL; + + attr->__flags = flags; + return 0; +} + +/* Get process group ID from the attribute structure. */ +inline static int +posix_spawnattr_getpgroup(const posix_spawnattr_t *attr, pid_t *pgroup) +{ + *pgroup = attr->__pgrp; + return 0; +} + +/* Store process group ID in the attribute structure. */ +inline static int +posix_spawnattr_setpgroup(posix_spawnattr_t *attr, pid_t pgroup) +{ + attr->__pgrp = pgroup; + return 0; +} + +/* Get scheduling policy from the attribute structure. */ +inline static int +posix_spawnattr_getschedpolicy(const posix_spawnattr_t *attr, + int *schedpolicy) +{ + *schedpolicy = attr->__policy; + return 0; +} + +/* Store scheduling policy in the attribute structure. */ +inline static int +posix_spawnattr_setschedpolicy(posix_spawnattr_t *attr, int schedpolicy) +{ + switch (schedpolicy) { + case SCHED_OTHER: + case SCHED_FIFO: + case SCHED_RR: + break; + default: + return EINVAL; + } + + attr->__policy = schedpolicy; + return 0; +} + +/* Get scheduling parameters from the attribute structure. */ +static inline int +posix_spawnattr_getschedparam(const posix_spawnattr_t *attr, + struct sched_param *schedparam) +{ + memcpy(schedparam, &attr->__sp, sizeof(attr->__sp)); + return 0; +} + +/* Store scheduling parameters in the attribute structure. */ +static inline int +posix_spawnattr_setschedparam(posix_spawnattr_t *attr, + const struct sched_param *schedparam) +{ + attr->__sp = *schedparam; + return 0; +} + +/* Initialize data structure for file attribute for `spawn' call. */ +inline static int +posix_spawn_file_actions_init(posix_spawn_file_actions_t *file_actions) +{ + memset(file_actions, 0, sizeof(*file_actions)); + return 0; +} + +/* Free resources associated with FILE-ACTIONS. */ +inline static int +posix_spawn_file_actions_destroy(posix_spawn_file_actions_t *file_actions) +{ + free(file_actions->__actions); + return 0; +} + +/* Add an action to FILE-ACTIONS which tells the implementation to call + `open' for the given file during the `spawn' call. */ +int posix_spawn_file_actions_addopen(posix_spawn_file_actions_t * restrict + file_actions, int fd, + const char * restrict path, + int oflag, mode_t mode) + __THROW; + +/* Add an action to FILE-ACTIONS which tells the implementation to call + `close' for the given file descriptor during the `spawn' call. */ +int posix_spawn_file_actions_addclose(posix_spawn_file_actions_t *file_actions, + int fd) + __THROW; + +/* Add an action to FILE-ACTIONS which tells the implementation to call + `dup2' for the given file descriptors during the `spawn' call. */ +int posix_spawn_file_actions_adddup2(posix_spawn_file_actions_t *file_actions, + int fd, int newfd) __THROW; + +__END_DECLS + +#endif /* spawn.h */ diff --git a/librt/Makefile.in b/librt/Makefile.in index 909afd8..857efb5 100644 --- a/librt/Makefile.in +++ b/librt/Makefile.in @@ -33,6 +33,14 @@ else librt_filter_SRC += clock_nanosleep.c clock_getcpuclockid.c clock_gettime.c librt_SSRC := endif + +librt_filter_SRC += $(if $(UCLIBC_HAS_ADVANCED_REALTIME),, \ + spawn.c \ + spawn_faction_addclose.c \ + spawn_faction_adddup2.c \ + spawn_faction_addopen.c \ + spawn_faction_init.c) + librt_SRC := $(filter-out $(librt_filter_SRC),$(librt_SRC)) librt_OBJ := $(patsubst %.c,$(librt_OUT)/%.o,$(librt_SRC)) diff --git a/librt/spawn.c b/librt/spawn.c new file mode 100644 index 0000000..b5935a1 --- /dev/null +++ b/librt/spawn.c @@ -0,0 +1,259 @@ +/* Copyright (C) 2000, 2011 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include +#include +#include +#include +#include +#include + +#include +#include + +#include +#include "spawn_int.h" + +/* The Unix standard contains a long explanation of the way to signal + an error after the fork() was successful. Since no new wait status + was wanted there is no way to signal an error using one of the + available methods. The committee chose to signal an error by a + normal program exit with the exit code 127. */ +#define SPAWN_ERROR 127 + +/* Execute file actions. + * Returns true on error. + */ +inline static bool execute_file_actions(const posix_spawn_file_actions_t *fa) +{ + struct rlimit64 fdlimit; + bool have_fdlimit = false; + + for (int cnt = 0; cnt < fa->__used; ++cnt) { + struct __spawn_action *action = &fa->__actions[cnt]; + + switch (action->tag) { + case spawn_do_close: + if (close_not_cancel(action->action.close_action.fd) != 0) { + if (!have_fdlimit) { + getrlimit64(RLIMIT_NOFILE, &fdlimit); + have_fdlimit = true; + } + + /* Only signal errors for file descriptors out of range. */ + if (0 > action->action.close_action.fd + || action->action.close_action.fd >= fdlimit.rlim_cur) + /* Signal the error. */ + return true; + } + break; + + case spawn_do_open:; + int new_fd = open_not_cancel(action->action.open_action.path, + action->action.open_action.oflag + | O_LARGEFILE, + action->action.open_action.mode); + + if (new_fd == -1) + return true; + + /* Make sure the desired file descriptor is used. */ + if (new_fd != action->action.open_action.fd) { + if (dup2(new_fd, action->action.open_action.fd) + != action->action.open_action.fd) + return true; + + if (close_not_cancel(new_fd) != 0) + return true; + } + break; + + case spawn_do_dup2: + if (dup2(action->action.dup2_action.fd, + action->action.dup2_action.newfd) + != action->action.dup2_action.newfd) + return true; + break; + } + } + + return false; +} + +#define DANGEROUS (POSIX_SPAWN_SETSIGMASK \ + | POSIX_SPAWN_SETSIGDEF \ + | POSIX_SPAWN_SETSCHEDPARAM \ + | POSIX_SPAWN_SETSCHEDULER \ + | POSIX_SPAWN_SETPGROUP \ + | POSIX_SPAWN_RESETIDS) +inline static bool is_vfork_safe(short int flags) +{ + return ((flags & POSIX_SPAWN_USEVFORK) || !(flags & DANGEROUS)); +} + + +/* Spawn a new process executing PATH with the attributes describes in *ATTRP. + Before running the process perform the actions described in FILE-ACTIONS. */ +static int +__spawni(pid_t *pid, const char *file, + const posix_spawn_file_actions_t *fa, + const posix_spawnattr_t *attrp, char *const argv[], + char *const envp[], const char *path) +{ + short int flags = attrp ? attrp->__flags : 0; + + pid_t new_pid; + if (is_vfork_safe(flags) && !fa) + new_pid = vfork(); + else + new_pid = fork(); + + if (new_pid) { + if (new_pid < 0) + return errno; + + if (pid) + *pid = new_pid; + + return 0; + } + + if (flags & POSIX_SPAWN_SETSIGMASK) { + if (sigprocmask(SIG_SETMASK, &attrp->__ss, NULL) != 0) + goto error; + } + + if (flags & POSIX_SPAWN_SETSIGDEF) { + /* We have to iterate over all signals. This could possibly be + done better but it requires system specific solutions since + the sigset_t data type can be very different on different + architectures. */ + struct sigaction sa; + + memset(&sa, 0, sizeof(sa)); + sa.sa_handler = SIG_DFL; + + for (int sig = 1; sig <= _NSIG; ++sig) { + if (sigismember(&attrp->__sd, sig)) { + if (sigaction(sig, &sa, NULL) != 0) + goto error; + } + } + } + + if (flags & POSIX_SPAWN_SETSCHEDULER) { + if (sched_setscheduler(0, attrp->__policy, &attrp->__sp) == -1) + goto error; + } else if (flags & POSIX_SPAWN_SETSCHEDPARAM) { + if (sched_setparam(0, &attrp->__sp) == -1) + goto error; + } + + if (flags & POSIX_SPAWN_SETPGROUP) { + if (setpgid(0, attrp->__pgrp) != 0) + goto error; + } + + if (flags & POSIX_SPAWN_RESETIDS) { + if (seteuid(getuid()) || setegid(getgid())) + goto error; + } + + if (fa && execute_file_actions(fa)) + goto error; + + if (!path || strchr(file, '/')) { + execve(file, argv, envp); + goto error; + } + + + char *name; + { + size_t filelen = strlen(file) + 1; + size_t pathlen = strlen(path) + 1; + name = alloca(pathlen + filelen); + + /* Copy the file name at the top. */ + name = (char *) memcpy(name + pathlen, file, filelen); + + /* And add the slash. */ + *--name = '/'; + } + + char *p; + do { + char *startp; + p = strchrnul(path, ':'); + + /* Two adjacent colons, or a colon at the beginning or the end + of `PATH' means to search the current directory. */ + if (p == path) + startp = name + 1; + else + startp = (char *) memcpy(name - (p - path), path, p - path); + + execve(startp, argv, envp); + + switch (errno) { + case EACCES: + case ENOENT: + case ESTALE: + case ENOTDIR: + /* Those errors indicate the file is missing or not + executable by us, in which case we want to just try + the next path directory. */ + break; + default: + /* Some other error means we found an executable file, + but something went wrong executing it; return the + error to our caller. */ + goto error; + } + + path = p; + } while (*p++ != '\0'); + +error: + _exit(SPAWN_ERROR); +} + +/* Spawn a new process executing PATH with the attributes describes in *ATTRP. + Before running the process perform the actions described in FILE-ACTIONS. */ +int posix_spawn (pid_t *pid, const char *path, + const posix_spawn_file_actions_t *fa, + const posix_spawnattr_t *attrp, char *const argv[], + char *const envp[]) +{ + return __spawni(pid, path, fa, attrp, argv, envp, NULL); +} + +/* Spawn a new process executing FILE with the attributes describes in *ATTRP. + Before running the process perform the actions described in FILE-ACTIONS. */ +int +posix_spawnp(pid_t *pid, const char *file, + const posix_spawn_file_actions_t *fa, + const posix_spawnattr_t *attrp, char *const argv[], + char *const envp[]) +{ + const char *path = getenv("PATH"); + + if (!path) + path = ":/bin:/usr/bin"; + + return __spawni(pid, file, fa, attrp, argv, envp, path); +} diff --git a/librt/spawn_faction_addclose.c b/librt/spawn_faction_addclose.c new file mode 100644 index 0000000..b418f96 --- /dev/null +++ b/librt/spawn_faction_addclose.c @@ -0,0 +1,51 @@ +/* Copyright (C) 2000 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include +#include +#include + +#include "spawn_int.h" + +/* Add an action to FILE-ACTIONS which tells the implementation to call + `close' for the given file descriptor during the `spawn' call. */ +int +posix_spawn_file_actions_addclose(posix_spawn_file_actions_t *file_actions, + int fd) +{ + int maxfd = sysconf(_SC_OPEN_MAX); + struct __spawn_action *rec; + + /* Test for the validity of the file descriptor. */ + if (fd < 0 || fd >= maxfd) + return EBADF; + + /* Allocate more memory if needed. */ + if (file_actions->__used == file_actions->__allocated + && __posix_spawn_file_actions_realloc(file_actions) != 0) + /* This can only mean we ran out of memory. */ + return ENOMEM; + + /* Add the new value. */ + rec = &file_actions->__actions[file_actions->__used]; + rec->tag = spawn_do_close; + rec->action.open_action.fd = fd; + + /* Account for the new entry. */ + ++file_actions->__used; + return 0; +} diff --git a/librt/spawn_faction_adddup2.c b/librt/spawn_faction_adddup2.c new file mode 100644 index 0000000..6d73313 --- /dev/null +++ b/librt/spawn_faction_adddup2.c @@ -0,0 +1,52 @@ +/* Copyright (C) 2000 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include +#include +#include + +#include "spawn_int.h" + +/* Add an action to FILE-ACTIONS which tells the implementation to call + `dup2' for the given file descriptors during the `spawn' call. */ +int +posix_spawn_file_actions_adddup2(posix_spawn_file_actions_t *file_actions, + int fd, int newfd) +{ + int maxfd = sysconf(_SC_OPEN_MAX); + struct __spawn_action *rec; + + /* Test for the validity of the file descriptor. */ + if (fd < 0 || newfd < 0 || fd >= maxfd || newfd >= maxfd) + return EBADF; + + /* Allocate more memory if needed. */ + if (file_actions->__used == file_actions->__allocated + && __posix_spawn_file_actions_realloc (file_actions) != 0) + /* This can only mean we ran out of memory. */ + return ENOMEM; + + /* Add the new value. */ + rec = &file_actions->__actions[file_actions->__used]; + rec->tag = spawn_do_dup2; + rec->action.dup2_action.fd = fd; + rec->action.dup2_action.newfd = newfd; + + /* Account for the new entry. */ + ++file_actions->__used; + return 0; +} diff --git a/librt/spawn_faction_addopen.c b/librt/spawn_faction_addopen.c new file mode 100644 index 0000000..285ca71 --- /dev/null +++ b/librt/spawn_faction_addopen.c @@ -0,0 +1,55 @@ +/* Copyright (C) 2000 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include +#include +#include + +#include "spawn_int.h" + +/* Add an action to FILE-ACTIONS which tells the implementation to call + `open' for the given file during the `spawn' call. */ +int +posix_spawn_file_actions_addopen(posix_spawn_file_actions_t *file_actions, + int fd, const char *path, int oflag, + mode_t mode) +{ + int maxfd = sysconf(_SC_OPEN_MAX); + struct __spawn_action *rec; + + /* Test for the validity of the file descriptor. */ + if (fd < 0 || fd >= maxfd) + return EBADF; + + /* Allocate more memory if needed. */ + if (file_actions->__used == file_actions->__allocated + && __posix_spawn_file_actions_realloc (file_actions) != 0) + /* This can only mean we ran out of memory. */ + return ENOMEM; + + /* Add the new value. */ + rec = &file_actions->__actions[file_actions->__used]; + rec->tag = spawn_do_open; + rec->action.open_action.fd = fd; + rec->action.open_action.path = path; + rec->action.open_action.oflag = oflag; + rec->action.open_action.mode = mode; + + /* Account for the new entry. */ + ++file_actions->__used; + return 0; +} diff --git a/librt/spawn_faction_init.c b/librt/spawn_faction_init.c new file mode 100644 index 0000000..fb398a5 --- /dev/null +++ b/librt/spawn_faction_init.c @@ -0,0 +1,42 @@ +/* Copyright (C) 2000 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include +#include +#include +#include + +#include "spawn_int.h" + + +/* Function used to increase the size of the allocated array. This + function is called from the `add'-functions. */ +int +__posix_spawn_file_actions_realloc(posix_spawn_file_actions_t *file_actions) +{ + int newalloc = file_actions->__allocated + 8; + void *newmem = realloc(file_actions->__actions, + newalloc * sizeof(struct __spawn_action)); + + if (newmem == NULL) + /* Not enough memory. */ + return ENOMEM; + + file_actions->__actions = (struct __spawn_action *)newmem; + file_actions->__allocated = newalloc; + return 0; +} diff --git a/librt/spawn_int.h b/librt/spawn_int.h new file mode 100644 index 0000000..89c88db --- /dev/null +++ b/librt/spawn_int.h @@ -0,0 +1,26 @@ +/* Data structure to contain the action information. */ +struct __spawn_action { + enum { + spawn_do_close, + spawn_do_dup2, + spawn_do_open + } tag; + + union { + struct { + int fd; + } close_action; + struct { + int fd; + int newfd; + } dup2_action; + struct { + int fd; + const char *path; + int oflag; + mode_t mode; + } open_action; + } action; +}; + +int __posix_spawn_file_actions_realloc(posix_spawn_file_actions_t *fa); -- 1.8.4