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-rw-r--r--libc/sysdeps/linux/i386/Makefile21
-rw-r--r--libc/sysdeps/linux/i386/crt1.S125
2 files changed, 132 insertions, 14 deletions
diff --git a/libc/sysdeps/linux/i386/Makefile b/libc/sysdeps/linux/i386/Makefile
index d9bf0239a..e29707f0e 100644
--- a/libc/sysdeps/linux/i386/Makefile
+++ b/libc/sysdeps/linux/i386/Makefile
@@ -19,10 +19,9 @@
TOPDIR=../../../../
include $(TOPDIR)Rules.mak
-CRT0_SRC = crt0.S
-CRT0_OBJ = crt0.o crt1.o
-SCRT0_OBJ = $(patsubst %,S%, $(CRT0_OBJ))
-CRT0_DEPS=gmon-start.S
+CRT_SRC = crt1.S
+CRT_OBJ = crt1.o
+SCRT_OBJ = $(patsubst %,S%, $(CRT_OBJ))
CTOR_TARGETS=$(TOPDIR)lib/crti.o $(TOPDIR)lib/crtn.o
SSRC=__longjmp.S vfork.S clone.S setjmp.S bsd-setjmp.S \
@@ -38,21 +37,16 @@ OBJ_LIST=../../../obj.sysdeps.$(TARGET_ARCH)
all: $(OBJ_LIST)
-$(OBJ_LIST): $(OBJS) $(CRT0_OBJ) $(SCRT0_OBJ) $(CTOR_TARGETS)
+$(OBJ_LIST): $(OBJS) $(CRT_OBJ) $(SCRT_OBJ) $(CTOR_TARGETS)
echo $(patsubst %, sysdeps/linux/$(TARGET_ARCH)/%, $(OBJS)) > $(OBJ_LIST)
$(INSTALL) -d $(TOPDIR)lib/
- cp $(CRT0_OBJ) $(SCRT0_OBJ) $(TOPDIR)lib/
-ifeq ($(strip $(UCLIBC_CTOR_DTOR)),y)
- $(RM) $(TOPDIR)lib/Scrt0.o
-else
- mv $(TOPDIR)lib/Scrt0.o $(TOPDIR)lib/Scrt1.o
-endif
+ cp $(CRT_OBJ) $(SCRT_OBJ) $(TOPDIR)lib/
-$(CRT0_OBJ): $(CRT0_SRC)
+$(CRT_OBJ): $(CRT_SRC)
$(CC) $(ASFLAGS) -DL_$* $< -c -o $*.o
$(STRIPTOOL) -x -R .note -R .comment $*.o
-$(SCRT0_OBJ): $(CRT0_SRC)
+$(SCRT_OBJ): $(CRT_SRC)
$(CC) $(ASFLAGS) $(PIEFLAG) -DL_$* $< -c -o $*.o
$(STRIPTOOL) -x -R .note -R .comment $*.o
@@ -94,4 +88,3 @@ clean:
$(RM) *.[oa] *~ core
$(RM) bits/sysnum.h
$(RM) $(TOPDIR)/include/fpu_control.h
- $(RM) gmon-start.S
diff --git a/libc/sysdeps/linux/i386/crt1.S b/libc/sysdeps/linux/i386/crt1.S
new file mode 100644
index 000000000..76e71be56
--- /dev/null
+++ b/libc/sysdeps/linux/i386/crt1.S
@@ -0,0 +1,125 @@
+/* Copyright (C) 1991, 1992 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. */
+
+
+/* Based on the code from GNU libc, but hacked up by John Beppu and Erik Andersen */
+/* adapted by PaX Team for ET_DYN/PIE binaries */
+
+/*
+ When we enter this piece of code, the program stack looks like this:
+ argc argument counter (integer)
+ argv[0] program name (pointer)
+ argv[1...N] program args (pointers)
+ argv[argc-1] end of args (integer)
+ NULL
+ env[0...N] environment variables (pointers)
+ NULL
+*/
+
+#include <features.h>
+
+.text
+ .align 4
+
+ .global _start
+ .type _start,%function
+ .weak _init
+ .weak _fini
+ .type __uClibc_start_main,%function
+
+_start:
+ /* locate the start of the environment variables */
+ popl %ecx /* Store argc into %ecx */
+ movl %esp,%ebx /* Store argv into ebx */
+ movl %esp,%eax /* Store argv into eax as well*/
+ movl %edx,%esi /* Store edx(FINI ptr) in %esi */
+ movl %ecx,%edx /* Stick argc into %edx so we can do some math in a sec */
+ leal 4(%eax,%edx,4),%eax
+
+ /* [ register layout ]
+
+ sizeof(char*) == 4
+ %ecx = argc ; 0(esp)
+ %ebx = argv ; 4(esp)
+ %eax = env ; argv + (argc * 4) + 4
+ */
+ xorl %ebp,%ebp /* NULL */
+ /*
+ Before pushing the arguments align the stack to a 16-byte
+ (SSE needs 16-byte alignment) boundary to avoid penalties from
+ misaligned accesses. Thanks to Edward Seidl <seidl@janed.com>
+ for pointing this out.
+ */
+ andl $0xfffffff0, %esp
+ /* Push NULL to make sure stack ptr
+ is 16 byte aligned when calling __uClibc_start_main */
+ pushl %ebp
+ pushl %ebp
+
+ /* Set up an invalid (NULL return address, NULL frame pointer)
+ callers stack frame so anybody unrolling the stack knows where
+ to stop */
+ pushl %ebp /* callers %cs */
+ pushl %ebp /* callers %eip (return address) */
+ pushl %ebp /* callers %ebp (frame pointer) */
+ movl %esp,%ebp /* mark callers stack frame as invalid */
+
+#if defined L_Scrt1
+ call .L0
+.L0:
+ pop %edx
+ addl $_GLOBAL_OFFSET_TABLE_+[.-.L0],%edx
+#endif
+ pushl %esi /* Push FINI pointer */
+
+ /* Push apps .init, .fini and main arguments to __uClibc_start_main() on the stack */
+#ifdef L_Scrt1
+ pushl main@GOT(%edx)
+ pushl _fini@GOT(%edx)
+ pushl _init@GOT(%edx)
+#else
+ pushl $main
+ pushl $_fini
+ pushl $_init
+#endif
+
+ /* Push envp, argc, and argc arguments to __uClibc_start_main() on the stack */
+ pushl %eax /* Environment pointer */
+ pushl %ebx /* Argument pointer */
+ pushl %ecx /* And the argument count */
+
+ /* Ok, now run uClibc's main() -- shouldn't return */
+#ifdef L_Scrt1
+ call *__uClibc_start_main@GOT(%edx)
+#else
+ call __uClibc_start_main
+#endif
+
+ /* Crash if somehow `exit' returns anyways. */
+ hlt
+.size _start,.-_start
+
+
+/* Define a symbol for the first piece of initialized data. */
+ .data
+ .globl __data_start
+__data_start:
+ .long 0
+ .weak data_start
+ data_start = __data_start
+