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-rw-r--r--elf/Makefile5
-rw-r--r--elf/sofini.c9
-rw-r--r--elf/soinit.c38
3 files changed, 50 insertions, 2 deletions
diff --git a/elf/Makefile b/elf/Makefile
index b0923b2b6d..0065d2ba47 100644
--- a/elf/Makefile
+++ b/elf/Makefile
@@ -31,12 +31,13 @@ LDFLAGS-dl.so	:= -e 0 # work around ld bug
 
 rtld-routines	:= rtld $(addprefix dl-,load lookup object reloc	\
 				        runtime sysdep error init fini)
-distribute	= $(rtld-routines:=.c) dynamic-link.h do-rel.h
+distribute	= $(rtld-routines:=.c) dynamic-link.h do-rel.h \
+		  soinit.c sofini.c
 
 include ../Makeconfig
 
 ifeq (yes,$(build-shared))
-extra-objs	= $(rtld-routines:=.so)
+extra-objs	= $(rtld-routines:=.so) soinit.so sofini.so
 install-lib	= ld.so
 endif
 
diff --git a/elf/sofini.c b/elf/sofini.c
new file mode 100644
index 0000000000..e44041b5ec
--- /dev/null
+++ b/elf/sofini.c
@@ -0,0 +1,9 @@
+/* Finalizer module for ELF shared C library.  This provides terminating
+   null pointer words in the `.ctors' and `.dtors' sections.  */
+
+static void (*const __CTOR_END__[1]) (void)
+     __attribute__ ((unused, section (".ctors")))
+     = { 0 };
+static void (*const __DTOR_END__[1]) (void)
+     __attribute__ ((unused, section (".dtors")))
+     = { 0 };
diff --git a/elf/soinit.c b/elf/soinit.c
new file mode 100644
index 0000000000..0310b74b93
--- /dev/null
+++ b/elf/soinit.c
@@ -0,0 +1,38 @@
+/* Initializer module for building the ELF shared C library.  This file and
+   sofini.c do the work normally done by crtbeginS.o and crtendS.o, to wrap
+   the `.ctors' and `.dtors' sections so the lists are terminated, and
+   calling those lists of functions.  */
+
+static void (*const __CTOR_LIST__[1]) (void)
+     __attribute__ ((section (".ctors")))
+     = { (void (*) (void)) -1 };
+static void (*const __DTOR_LIST__[1]) (void)
+     __attribute__ ((section (".dtors")))
+     = { (void (*) (void)) -1 };
+
+static inline void
+run_hooks (void (*const list[]) (void))
+{
+  while (*++list)
+    (**list) ();
+}
+
+
+/* This function will be called from _init in init-first.c.  */
+void
+__libc_global_ctors (void)
+{
+  /* Call constructor functions.  */
+  run_hooks (__CTOR_LIST__);
+}
+
+
+/* This function becomes the DT_FINI termination function
+   for the C library.  */
+void _fini (void) __attribute__ ((section (".fini"))); /* Just for kicks.  */
+void
+_fini (void)
+{
+  /* Call destructor functions.  */
+  run_hooks (__DTOR_LIST__);
+}