X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=liblttng-ust-fork%2Fustfork.c;h=43b8d8f69a39e3683f59a02d1a4db76b990df3f2;hb=702d1b7d91bc75f4fc01415fc625af1b834ddec4;hp=5e6acba16e87fb9893ee7c9fe3b756afae12dd38;hpb=69400ac4a4e6575f749c6326df7c2a2c8ac3bdc5;p=lttng-ust.git

diff --git a/liblttng-ust-fork/ustfork.c b/liblttng-ust-fork/ustfork.c
index 5e6acba1..43b8d8f6 100644
--- a/liblttng-ust-fork/ustfork.c
+++ b/liblttng-ust-fork/ustfork.c
@@ -1,6 +1,6 @@
 /*
  * Copyright (C) 2009  Pierre-Marc Fournier
- * Copyright (C) 2011  Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ * Copyright (C) 2011-2012  Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -18,48 +18,79 @@
  */
 
 #define _GNU_SOURCE
-#include <dlfcn.h>
+#include <lttng/ust-dlfcn.h>
 #include <unistd.h>
 #include <stdio.h>
 #include <signal.h>
 #include <sched.h>
 #include <stdarg.h>
-#include "usterr.h"
+#include <errno.h>
 
 #include <lttng/ust.h>
 
-struct user_desc;
-
 pid_t fork(void)
 {
 	static pid_t (*plibc_func)(void) = NULL;
-	ust_fork_info_t fork_info;
+	sigset_t sigset;
 	pid_t retval;
 
 	if (plibc_func == NULL) {
 		plibc_func = dlsym(RTLD_NEXT, "fork");
 		if (plibc_func == NULL) {
 			fprintf(stderr, "libustfork: unable to find \"fork\" symbol\n");
+			errno = ENOSYS;
 			return -1;
 		}
 	}
 
-	ust_before_fork(&fork_info);
+	ust_before_fork(&sigset);
 	/* Do the real fork */
 	retval = plibc_func();
 	if (retval == 0) {
 		/* child */
-		ust_after_fork_child(&fork_info);
+		ust_after_fork_child(&sigset);
+	} else {
+		ust_after_fork_parent(&sigset);
+	}
+	return retval;
+}
+
+int daemon(int nochdir, int noclose)
+{
+	static int (*plibc_func)(int nochdir, int noclose) = NULL;
+	sigset_t sigset;
+	int retval;
+
+	if (plibc_func == NULL) {
+		plibc_func = dlsym(RTLD_NEXT, "daemon");
+		if (plibc_func == NULL) {
+			fprintf(stderr, "libustfork: unable to find \"daemon\" symbol\n");
+			errno = ENOSYS;
+			return -1;
+		}
+	}
+
+	ust_before_fork(&sigset);
+	/* Do the real daemon call */
+	retval = plibc_func(nochdir, noclose);
+	if (retval == 0) {
+		/* child, parent called _exit() directly */
+		ust_after_fork_child(&sigset);
 	} else {
-		ust_after_fork_parent(&fork_info);
+		/* on error in the parent */
+		ust_after_fork_parent(&sigset);
 	}
 	return retval;
 }
 
+#ifdef __linux__
+
+struct user_desc;
+
 struct ustfork_clone_info {
 	int (*fn)(void *);
 	void *arg;
-	ust_fork_info_t fork_info;
+	sigset_t sigset;
 };
 
 static int clone_fn(void *arg)
@@ -67,7 +98,7 @@ static int clone_fn(void *arg)
 	struct ustfork_clone_info *info = (struct ustfork_clone_info *) arg;
 
 	/* clone is now done and we are in child */
-	ust_after_fork_child(&info->fork_info);
+	ust_after_fork_child(&info->sigset);
 	return info->fn(info->arg);
 }
 
@@ -94,6 +125,7 @@ int clone(int (*fn)(void *), void *child_stack, int flags, void *arg, ...)
 		plibc_func = dlsym(RTLD_NEXT, "clone");
 		if (plibc_func == NULL) {
 			fprintf(stderr, "libustfork: unable to find \"clone\" symbol.\n");
+			errno = ENOSYS;
 			return -1;
 		}
 	}
@@ -107,13 +139,52 @@ int clone(int (*fn)(void *), void *child_stack, int flags, void *arg, ...)
 				tls, ctid);
 	} else {
 		/* Creating a real process, we need to intervene. */
-		struct ustfork_clone_info info = { fn: fn, arg: arg };
+		struct ustfork_clone_info info = { .fn = fn, .arg = arg };
 
-		ust_before_fork(&info.fork_info);
+		ust_before_fork(&info.sigset);
 		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);
+		ust_after_fork_parent(&info.sigset);
 	}
 	return retval;
 }
+
+#elif defined (__FreeBSD__)
+
+pid_t rfork(int flags)
+{
+	static pid_t (*plibc_func)(void) = NULL;
+	sigset_t sigset;
+	pid_t retval;
+
+	if (plibc_func == NULL) {
+		plibc_func = dlsym(RTLD_NEXT, "rfork");
+		if (plibc_func == NULL) {
+			fprintf(stderr, "libustfork: unable to find \"rfork\" symbol\n");
+			errno = ENOSYS;
+			return -1;
+		}
+	}
+
+	ust_before_fork(&sigset);
+	/* Do the real rfork */
+	retval = plibc_func();
+	if (retval == 0) {
+		/* child */
+		ust_after_fork_child(&sigset);
+	} else {
+		ust_after_fork_parent(&sigset);
+	}
+	return retval;
+}
+
+/*
+ * On BSD, no need to override vfork, because it runs in the context of
+ * the parent, with parent waiting until execve or exit is executed in
+ * the child.
+ */
+
+#else
+#warning "Unknown OS. You might want to ensure that fork/clone/vfork/fork handling is complete."
+#endif