Rewritten.

diff --git a/sysdeps/unix/sysv/sysv4/linux/i386/sysdep.h b/sysdeps/unix/sysv/sysv4/linux/i386/sysdep.h
new file mode 100644 (file)
index 0000000..d0c1c10
--- /dev/null
+++ b/sysdeps/unix/sysv/sysv4/linux/i386/sysdep.h
@@ -0,0 +1,86 @@
+/* Copyright (C) 1992, 1993, 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.  */
+
+/* In the Linux/ELF world, C symbols are asm symbols.  */
+#define NO_UNDERSCORES
+
+/* There is some commonality.  */
+#include <sysdeps/unix/i386/sysdep.h>
+
+#ifdef ASSEMBLER
+
+/* Linux uses a negative return value to indicate syscall errors, unlike
+   most Unices, which use the condition codes' carry flag.  */
+#undef PSEUDO
+#define        PSEUDO(name, syscall_name, args)                                      \
+  .text;                                                                     \
+  .globl __syscall_error;                                                    \
+  ENTRY (name)                                                               \
+    movl $SYS_##syscall_name, %eax;                                          \
+    DO_CALL (args)                                                           \
+    testl %eax, %eax;                                                        \
+    jl JUMPTARGET(__syscall_error)
+
+
+/* Linux takes system call arguments in registers:
+
+       syscall number  %eax         call-clobbered
+       arg 1           %ebx         call-saved
+       arg 2           %ecx         call-clobbered
+       arg 3           %edx         call-clobbered
+       arg 4           %esi         call-saved
+       arg 5           %edi         call-saved
+
+   The stack layout upon entering the function is:
+
+       24(%esp)        Arg# 5
+       20(%esp)        Arg# 4
+       16(%esp)        Arg# 3
+       12(%esp)        Arg# 2
+        8(%esp)        Arg# 1
+        4(%esp)        Return address
+         (%esp)
+
+   (Of course a function with e.g. 3 argumentS does not have entries for
+   arguments 4 and 5.)
+
+   We put the arguments into registers from the stack, and save the
+   call-saved registers, by using the 386 `xchg' instruction to swap the
+   values in both directions.  */
+
+#undef DO_CALL
+#define DO_CALL(args)                                                        \
+    DOARGS_##args                                                            \
+    int $0x80;                                                               \
+    UNDOARGS_##args                                                          \
+
+#define        DOARGS_0        /* No arguments to frob.  */
+#define        UNDOARGS_0      /* No arguments to unfrob.  */
+#define        DOARGS_1        xchg 8(%esp), %ebx; DOARGS_0 /* Save %ebx on stack.  */
+#define        UNDOARGS_1      xchg 8(%esp), %ebx; UNDOARGS_0 /* Restore %ebx */
+#define        DOARGS_2        movel 12(%esp), %ecx; DOARGS_1
+#define        UNDOARGS_2      UNDOARGS_1 /* %ecx is clobbered.  */
+#define        DOARGS_3        movel 16(%esp), %edx; DOARGS_2
+#define        UNDOARGS_3      UNDOARGS_2 /* %edx is clobbered.  */
+#define        DOARGS_4        xchg 20(%esp), %esi; DOARGS_3 /* Save %esi on stack. */
+#define        UNDOARGS_4      xchg 20(%esp), %esi; UNDOARGS_3 /* Restore %esi.  */
+#define        DOARGS_5        xchg 24(%esp), %edi; DOARGS_3 /* Save %edi on stack. */
+#define        UNDOARGS_5      xchg 24(%esp), %edi; UNDOARGS_3 /* Restore %edi.  */
+
+
+#endif /* ASSEMBLER */