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-rw-r--r--csu/Makefile84
-rw-r--r--csu/initfini.c85
2 files changed, 169 insertions, 0 deletions
diff --git a/csu/Makefile b/csu/Makefile
new file mode 100644
index 0000000000..6de77b768c
--- /dev/null
+++ b/csu/Makefile
@@ -0,0 +1,84 @@
+# Makefile for csu code for GNU C library.
+
+# Copyright (C) 1995 Free Software Foundation, Inc.
+# This file is part of the GNU C Library.
+
+# The GNU C Library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Library General Public License
+# as published by the Free Software Foundation; either version 2 of
+# the License, or (at your option) any later version.
+
+# The GNU C 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
+# Library General Public License for more details.
+
+# You should have received a copy of the GNU Library General Public
+# License along with the GNU C Library; see the file COPYING.LIB.  If
+# not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+# Cambridge, MA 02139, USA.
+
+# This directory contains the C startup code (that which calls main).  This
+# consists of the startfile, built from start.c and installed as crt0.o
+# (traditionally) or crt1.o (for ELF); and some initialization code which
+# is in the C library itself.  In ELF we also install crti.o and crtn.o,
+# special "initializer" and "finalizer" files in used in the link to make
+# the .init and .fini sections work right; both these files are built (in
+# an arcane manner) from initfini.c.
+
+subdir := csu
+
+csu-dummies = $(filter-out $(start-installed-name),crt1.o Mcrt1.o)
+extra-objs = start.o $(start-installed-name) $(csu-dummies)
+omit-deps = $(patsubst %.o,%,$(start-installed-name) $(csu-dummies))
+install-lib = $(start-installed-name) $(csu-dummies)
+distribute = initfini.c
+
+all: # Make this the default target; it will be defined in Rules.
+
+include ../Makeconfig
+
+ifneq ($(elf),yes)
+# When not using ELF, there is just one startfile, called crt0.o.
+start-installed-name = crt0.o
+else
+# In the ELF universe, crt0.o is called crt1.o, and there are 
+# some additional bizarre files.
+start-installed-name = crt1.o
+install-lib += crti.o crtn.o
+extra-objs += crti.o crtn.o
+generated += crti.s crtn.s
+omit-deps += crti crtn
+
+# Compile initfini.c to assembly code, which contains embedded shell
+# commands that prodice crti.s-new and crtn.s-new when run.  We need to
+# disable emission of .size directives and debugging information, since
+# they will get confused by the splitting of the output we do.
+$(objpfx)cr%i.s $(objpfx)cr%n.s: initfini.c
+	-rm -f $(objpfx)crtcommon.tmp
+	(echo 'cat > crtcommon.tmp <<\EOF_common'; \
+	 $(CC) $< $(CPPFLAGS) $(CFLAGS) -finhibit-size-directive -g0 -S -o -; \
+	 echo 'EOF_common') | (cd $(@D); $(SHELL))
+	cat $(objpfx)crtcommon.tmp >> $(objpfx)crti.s-new
+	cat $(objpfx)crtcommon.tmp >> $(objpfx)crtn.s-new
+	rm -f $(objpfx)crtcommon.tmp
+	mv -f $(objpfx)crti.s-new $(objpfx)crti.s
+	mv -f $(objpfx)crtn.s-new $(objpfx)crtn.s
+endif
+
+
+include ../Rules
+
+# The startfile is installed under different names, so we just call our
+# source file `start.c' and copy to the installed name after compiling.
+$(objpfx)$(start-installed-name): $(objpfx)start.o
+	-rm -f $@
+	ln $< $@
+
+# These extra files are sometimes expected by system standard linking
+# procedures, but we have nothing for them to do.  So compile empty files.
+$(addprefix $(objpfx),$(filter-out $(start-installed-name),$(csu-dummies))):
+	cp /dev/null $(@:.o=.c)
+	$(COMPILE.c) $(@:.o=.c) $(OUTPUT_OPTION)
+	rm -f $(@:.o=.c)
+
diff --git a/csu/initfini.c b/csu/initfini.c
new file mode 100644
index 0000000000..ea16e62ffe
--- /dev/null
+++ b/csu/initfini.c
@@ -0,0 +1,85 @@
+/* Special .init and .fini section support.
+Copyright (C) 1995 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C 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
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+/* This file is compiled into assembly code which is then surrounded by the
+   lines `cat > crtcommon.tmp <<\EOF_common' and `EOF_common' and thus
+   becomes a shell script which creates three files of assembly code.
+
+   * The first file is crti.s-new; this puts a function prologue at the
+   beginning of the .init and .fini sections and defines global symbols for
+   those addresses, so they can be called as functions.
+
+   * The second file is crtn.s-new; this puts the corresponding function
+   epilogues in the .init and .fini sections.
+
+   * The third file is crtcommon.tmp, which is whatever miscellaneous cruft
+   the compiler generated at the end; it should be appended to both crti.s-new
+   and crtn.s-new.  */
+
+#include <stdlib.h>
+
+/* These declarations make the functions go in the right sections when
+   we define them below.  GCC syntax does not allow the attribute
+   specifications to be in the function definitions themselves.  */
+void _init (void) __attribute__ ((section (".init")));
+void _fini (void) __attribute__ ((section (".fini")));
+
+/* End the here document containing the initial common code.
+   Then move the output file crtcommon.tmp to crti.s-new and crtn.s-new.  */
+asm ("\nEOF_common\n\
+mv -f crtcommon.tmp crti.s-new\n\
+cp -f crti.s-new crtn.s-new");
+
+/* Append the .init prologue to crti.s-new.  */
+asm ("cat >> crti.s-new <<\\EOF.crti.init");
+void
+_init (void)
+{
+  /* End the here document containing the .init prologue code.
+     Then fetch the .section directive just written and append that
+     to crtn.s-new, followed by the function epilogue.  */
+  asm ("\nEOF.crti.init
+\n\
+	fgrep .init crti.s-new >>crtn.s-new\n\
+	cat >> crtn.s-new <<\\EOF.crtn.init");
+}
+
+/* End the here document containing the .init epilogue code.
+   Then append the .fini prologue to crti.s-new.  */
+asm ("\nEOF.crtn.init\
+\n\
+cat >> crti.s-new <<\\EOF.crti.fini");
+
+void
+_fini (void)
+{
+  /* End the here document containing the .fini prologue code.
+     Then fetch the .section directive just written and append that
+     to crtn.s-new, followed by the function epilogue.  */
+  asm ("\nEOF.crti.fini\
+\n\
+	fgrep .fini crti.s-new >>crtn.s-new\n\
+	cat >> crtn.s-new <<\\EOF.crtn.fini");
+}
+
+/* End the here document containing the .fini epilogue code.
+   Finally, put the remainder of the generated assembly into crtcommon.tmp.  */
+asm ("\nEOF.crtn.fini\
+\n\
+cat > crtcommon.tmp <<\\EOF_common");