fix distribution bugs for 0.4

[ust.git] / libinterfork / interfork.c

diff --git a/libinterfork/interfork.c b/libinterfork/interfork.c
index cfdd2c475b79ae016ff470c0bb04a4dd0b358bf2..ecc39e38ca78c3e413de26da20c99367b2c50554 100644 (file)
--- a/libinterfork/interfork.c
+++ b/libinterfork/interfork.c
@@ -19,14 +19,19 @@
 #include <dlfcn.h>
 #include <unistd.h>
 #include <stdio.h>
-#include "share/usterr.h"
+#include <signal.h>
+#include <ust/ust.h>
+#include <sched.h>
+#include <stdarg.h>
+#include <ust/tracectl.h>
+#include "usterr.h"
 
-extern void ust_fork(void);
-extern void ust_potential_exec(void);
+struct user_desc;
 
 pid_t fork(void)
 {
        static pid_t (*plibc_func)(void) = NULL;
+       ust_fork_info_t fork_info;
 
        pid_t retval;
 
@@ -38,10 +43,18 @@ pid_t fork(void)
                }
        }
 
+       ust_before_fork(&fork_info);
+
+       /* Do the real fork */
        retval = plibc_func();
 
-       if(retval == 0)
-               ust_fork();
+       if(retval == 0) {
+               /* child */
+               ust_after_fork_child(&fork_info);
+       }
+       else {
+               ust_after_fork_parent(&fork_info);
+       }
 
        return retval;
 }
@@ -55,7 +68,7 @@ int execve(const char *filename, char *const argv[], char *const envp[])
        if(plibc_func == NULL) {
                plibc_func = dlsym(RTLD_NEXT, "execve");
                if(plibc_func == NULL) {
-                       fprintf(stderr, "libcwrap: unable to find execve\n");
+                       fprintf(stderr, "libinterfork: unable to find execve\n");
                        return -1;
                }
        }
@@ -66,3 +79,65 @@ int execve(const char *filename, char *const argv[], char *const 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;
+}