X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=liblttng-ust-fork%2Fustfork.c;h=71c4b86c1189ff7f89e1f7edba541c5d69d98df5;hb=111902ab67af0b14edfe846c32940732543dbc1a;hp=cc6963b344419beaec236b24bc0831847e29103d;hpb=3678c8aaf5e2691aaeab0fe15430767138f245d9;p=lttng-ust.git

diff --git a/liblttng-ust-fork/ustfork.c b/liblttng-ust-fork/ustfork.c
index cc6963b3..71c4b86c 100644
--- a/liblttng-ust-fork/ustfork.c
+++ b/liblttng-ust-fork/ustfork.c
@@ -18,13 +18,13 @@
  */
 
 #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>
 
@@ -33,6 +33,7 @@ pid_t fork(void)
 	static pid_t (*plibc_func)(void) = NULL;
 	sigset_t sigset;
 	pid_t retval;
+	int saved_errno;
 
 	if (plibc_func == NULL) {
 		plibc_func = dlsym(RTLD_NEXT, "fork");
@@ -46,12 +47,45 @@ pid_t fork(void)
 	ust_before_fork(&sigset);
 	/* Do the real fork */
 	retval = plibc_func();
+	saved_errno = errno;
 	if (retval == 0) {
 		/* child */
 		ust_after_fork_child(&sigset);
 	} else {
 		ust_after_fork_parent(&sigset);
 	}
+	errno = saved_errno;
+	return retval;
+}
+
+int daemon(int nochdir, int noclose)
+{
+	static int (*plibc_func)(int nochdir, int noclose) = NULL;
+	sigset_t sigset;
+	int retval;
+	int saved_errno;
+
+	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);
+	saved_errno = errno;
+	if (retval == 0) {
+		/* child, parent called _exit() directly */
+		ust_after_fork_child(&sigset);
+	} else {
+		/* on error in the parent */
+		ust_after_fork_parent(&sigset);
+	}
+	errno = saved_errno;
 	return retval;
 }
 
@@ -86,6 +120,7 @@ int clone(int (*fn)(void *), void *child_stack, int flags, void *arg, ...)
 	/* end of var args */
 	va_list ap;
 	int retval;
+	int saved_errno;
 
 	va_start(ap, arg);
 	ptid = va_arg(ap, pid_t *);
@@ -109,16 +144,19 @@ int clone(int (*fn)(void *), void *child_stack, int flags, void *arg, ...)
 		 */
 		retval = plibc_func(fn, child_stack, flags, arg, ptid,
 				tls, ctid);
+		saved_errno = errno;
 	} 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.sigset);
 		retval = plibc_func(clone_fn, child_stack, flags, &info,
 				ptid, tls, ctid);
+		saved_errno = errno;
 		/* The child doesn't get here. */
 		ust_after_fork_parent(&info.sigset);
 	}
+	errno = saved_errno;
 	return retval;
 }
 
@@ -129,6 +167,7 @@ pid_t rfork(int flags)
 	static pid_t (*plibc_func)(void) = NULL;
 	sigset_t sigset;
 	pid_t retval;
+	int saved_errno;
 
 	if (plibc_func == NULL) {
 		plibc_func = dlsym(RTLD_NEXT, "rfork");
@@ -142,12 +181,14 @@ pid_t rfork(int flags)
 	ust_before_fork(&sigset);
 	/* Do the real rfork */
 	retval = plibc_func();
+	saved_errno = errno;
 	if (retval == 0) {
 		/* child */
 		ust_after_fork_child(&sigset);
 	} else {
 		ust_after_fork_parent(&sigset);
 	}
+	errno = saved_errno;
 	return retval;
 }