-/* Copyright (C) 2009 Pierre-Marc Fournier
- *
- * This 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.
- *
- * This 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 this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#define _GNU_SOURCE
-#include <dlfcn.h>
-#include <unistd.h>
-#include <stdio.h>
-#include <signal.h>
-#include <ust/ust.h>
-#include <sched.h>
-#include <stdarg.h>
-#include <ust/tracectl.h>
-#include "usterr.h"
-
-struct user_desc;
-
-pid_t fork(void)
-{
- static pid_t (*plibc_func)(void) = NULL;
- ust_fork_info_t fork_info;
-
- pid_t retval;
-
- if(plibc_func == NULL) {
- plibc_func = dlsym(RTLD_NEXT, "fork");
- if(plibc_func == NULL) {
- fprintf(stderr, "libcwrap: unable to find fork\n");
- return -1;
- }
- }
-
- ust_before_fork(&fork_info);
-
- /* Do the real fork */
- retval = plibc_func();
-
- if(retval == 0) {
- /* child */
- ust_after_fork_child(&fork_info);
- }
- else {
- ust_after_fork_parent(&fork_info);
- }
-
- return retval;
-}
-
-int execve(const char *filename, char *const argv[], char *const envp[])
-{
- static int (*plibc_func)(const char *filename, char *const argv[], char *const envp[]) = NULL;
-
- pid_t retval;
-
- if(plibc_func == NULL) {
- plibc_func = dlsym(RTLD_NEXT, "execve");
- if(plibc_func == NULL) {
- fprintf(stderr, "libinterfork: unable to find execve\n");
- return -1;
- }
- }
-
- ust_potential_exec();
-
- retval = plibc_func(filename, argv, envp);
-
- return retval;
-}
-
-struct interfork_clone_info {
- int (*fn)(void *);
- void *arg;
- ust_fork_info_t fork_info;
-};
-
-static int clone_fn(void *arg)
-{
- struct interfork_clone_info *info = (struct interfork_clone_info *)arg;
-
- /* clone is now done and we are in child */
- ust_after_fork_child(&info->fork_info);
-
- return info->fn(info->arg);
-}
-
-int clone(int (*fn)(void *), void *child_stack, int flags, void *arg, ...)
-{
- static int (*plibc_func)(int (*fn)(void *), void *child_stack, int flags, void *arg, pid_t *ptid, struct user_desc *tls, pid_t *ctid) = NULL;
-
- /* varargs */
- pid_t *ptid;
- struct user_desc *tls;
- pid_t *ctid;
-
- int retval;
-
- va_list ap;
-
- va_start(ap, arg);
- ptid = va_arg(ap, pid_t *);
- tls = va_arg(ap, struct user_desc *);
- ctid = va_arg(ap, pid_t *);
- va_end(ap);
-
- if(plibc_func == NULL) {
- plibc_func = dlsym(RTLD_NEXT, "clone");
- if(plibc_func == NULL) {
- fprintf(stderr, "libinterfork: unable to find clone\n");
- return -1;
- }
- }
-
- if(flags & CLONE_VM) {
- /* creating a thread, no need to intervene, just pass on the arguments */
- retval = plibc_func(fn, child_stack, flags, arg, ptid, tls, ctid);
- }
- else {
- /* creating a real process, we need to intervene */
- struct interfork_clone_info info = { fn: fn, arg: arg };
-
- ust_before_fork(&info.fork_info);
-
- retval = plibc_func(clone_fn, child_stack, flags, &info, ptid, tls, ctid);
-
- /* The child doesn't get here */
- ust_after_fork_parent(&info.fork_info);
- }
-
- return retval;
-}