glibc2.2 fixes - more command line options - misc doc fixes

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@46 c046a42c-6fe2-441c-8c8c-71466251a162

Changelog

@@ -1,3 +1,9 @@
+version 0.1.1:
+
+ - glibc 2.2 compilation fixes
+ - added -s and -L options
+ - binary distribution of x86 glibc and wine
+
 version 0.1:
 
  - initial public release.

Makefile

@@ -118,6 +118,15 @@ tar:
 	( cd /tmp ; tar zcvf ~/$(FILE).tar.gz $(FILE) )
 	rm -rf /tmp/$(FILE)
 
+# generate a binary distribution including the test binary environnment 
+BINPATH=/usr/local/qemu-i386
+
+tarbin:
+	tar zcvf /tmp/qemu-i386-glibc21.tar.gz \
+                 $(BINPATH)/etc $(BINPATH)/lib $(BINPATH)/bin
+	tar zcvf /tmp/qemu-i386-wine.tar.gz \
+                 $(BINPATH)/X11R6 $(BINPATH)/wine
+
 ifneq ($(wildcard .depend),)
 include .depend
 endif

README

@@ -15,8 +15,22 @@ Type
 
     make install
 
-to install qemu in /usr/local/bin
+to install QEMU in /usr/local/bin
 
+* On x86 you should be able to launch any program by using the
+libraries installed on your PC. For example:
+
+    ./qemu -L / /bin/ls
+
+* On non x86 CPUs, you need first to download at least an x86 glibc
+(qemu-i386-glibc21.tar.gz on the qemu web page). Then you can launch
+the precompiled 'ls' x86 executable:
+
+    ./qemu /usr/local/qemu-i386/bin/ls
+
+You can look at /usr/local/qemu-i386/bin/qemu-conf.sh so that QEMU is
+automatically launched by the Linux kernel when you try to launch x86
+executables.
 
 Documentation
 -------------

VERSION

@@ -1 +1 @@
-0.1
+0.1.1

cpu-i386.h

@@ -406,7 +406,7 @@ void cpu_x86_close(CPUX86State *s);
 /* needed to load some predefinied segment registers */
 void cpu_x86_load_seg(CPUX86State *s, int seg_reg, int selector);
 
-/* you can call these signal handler from you SIGBUS and SIGSEGV
+/* you can call this signal handler from your SIGBUS and SIGSEGV
    signal handlers to inform the virtual CPU of exceptions. non zero
    is returned if the signal was handled by the virtual CPU.  */
 struct siginfo;

exec-i386.c

@@ -485,6 +485,10 @@ int cpu_x86_signal_handler(int host_signum, struct siginfo *info,
     unsigned long pc;
     sigset_t *pold_set;
     
+#ifndef REG_EIP
+/* for glibc 2.1 */
+#define REG_EIP EIP
+#endif
     pc = uc->uc_mcontext.gregs[EIP];
     pold_set = &uc->uc_sigmask;
     return handle_cpu_signal(pc, pold_set);

linux-user/elfload.c

@@ -42,8 +42,7 @@
 #define DLINFO_ITEMS 12
 
 /* Where we find X86 libraries... */
-//#define X86_DEFAULT_LIB_DIR	"/usr/x86/"
-#define X86_DEFAULT_LIB_DIR	"/"
+
 
 //extern void * mmap4k();
 #define mmap4k(a, b, c, d, e, f) mmap((void *)(a), b, c, d, e, f)
@@ -638,7 +637,8 @@ static int load_elf_binary(struct linux_binprm * bprm, struct target_pt_regs * r
 	     * is an a.out format binary
 	     */
 
-	    elf_interpreter = (char *)malloc(elf_ppnt->p_filesz+strlen(X86_DEFAULT_LIB_DIR));
+	    elf_interpreter = (char *)malloc(elf_ppnt->p_filesz+
+                                             strlen(bprm->interp_prefix));
 
 	    if (elf_interpreter == NULL) {
 		free (elf_phdata);
@@ -646,11 +646,11 @@ static int load_elf_binary(struct linux_binprm * bprm, struct target_pt_regs * r
 		return -ENOMEM;
 	    }
 
-	    strcpy(elf_interpreter, X86_DEFAULT_LIB_DIR);
+	    strcpy(elf_interpreter, bprm->interp_prefix);
 	    retval = lseek(bprm->fd, elf_ppnt->p_offset, SEEK_SET);
 	    if(retval >= 0) {
 		retval = read(bprm->fd, 
-			      elf_interpreter+strlen(X86_DEFAULT_LIB_DIR), 
+			      elf_interpreter+strlen(bprm->interp_prefix), 
 			      elf_ppnt->p_filesz);
 	    }
 	    if(retval < 0) {
@@ -911,7 +911,8 @@ static int load_elf_binary(struct linux_binprm * bprm, struct target_pt_regs * r
 
 
 
-int elf_exec(const char * filename, char ** argv, char ** envp, 
+int elf_exec(const char *interp_prefix, 
+             const char * filename, char ** argv, char ** envp, 
              struct target_pt_regs * regs, struct image_info *infop)
 {
         struct linux_binprm bprm;
@@ -930,6 +931,7 @@ int elf_exec(const char * filename, char ** argv, char ** envp,
 	else {
 	    bprm.fd = retval;
 	}
+        bprm.interp_prefix = (char *)interp_prefix;
         bprm.filename = (char *)filename;
         bprm.sh_bang = 0;
         bprm.loader = 0;

linux-user/main.c

@@ -32,6 +32,7 @@
 
 FILE *logfile = NULL;
 int loglevel;
+const char *interp_prefix = CONFIG_QEMU_PREFIX "/qemu-i386";
 
 /* XXX: on x86 MAP_GROWSDOWN only works if ESP <= address + 32, so
    we allocate a bigger stack. Need a better solution, for example
@@ -172,9 +173,16 @@ void cpu_loop(struct CPUX86State *env)
 void usage(void)
 {
     printf("qemu version " QEMU_VERSION ", Copyright (c) 2003 Fabrice Bellard\n"
-           "usage: qemu [-d] program [arguments...]\n"
+           "usage: qemu [-h] [-d] [-L path] [-s size] program [arguments...]\n"
            "Linux x86 emulator\n"
-           );
+           "\n"
+           "-h        print this help\n"
+           "-d        activate log (logfile=%s)\n"
+           "-L path   set the x86 elf interpreter prefix (default=%s)\n"
+           "-s size   set the x86 stack size in bytes (default=%ld)\n",
+           DEBUG_LOGFILE,
+           interp_prefix, 
+           x86_stack_size);
     exit(1);
 }
 
@@ -188,15 +196,41 @@ int main(int argc, char **argv)
     struct image_info info1, *info = &info1;
     CPUX86State *env;
     int optind;
-
+    const char *r;
+    
     if (argc <= 1)
         usage();
     loglevel = 0;
     optind = 1;
-    if (argv[optind] && !strcmp(argv[optind], "-d")) {
-        loglevel = 1;
+    for(;;) {
+        if (optind >= argc)
+            break;
+        r = argv[optind];
+        if (r[0] != '-')
+            break;
         optind++;
+        r++;
+        if (!strcmp(r, "-")) {
+            break;
+        } else if (!strcmp(r, "d")) {
+            loglevel = 1;
+        } else if (!strcmp(r, "s")) {
+            r = argv[optind++];
+            x86_stack_size = strtol(r, (char **)&r, 0);
+            if (x86_stack_size <= 0)
+                usage();
+            if (*r == 'M')
+                x86_stack_size *= 1024 * 1024;
+            else if (*r == 'k' || *r == 'K')
+                x86_stack_size *= 1024;
+        } else if (!strcmp(r, "L")) {
+            interp_prefix = argv[optind++];
+        } else {
+            usage();
+        }
     }
+    if (optind >= argc)
+        usage();
     filename = argv[optind];
 
     /* init debug */
@@ -215,7 +249,7 @@ int main(int argc, char **argv)
     /* Zero out image_info */
     memset(info, 0, sizeof(struct image_info));
 
-    if(elf_exec(filename, argv+optind, environ, regs, info) != 0) {
+    if(elf_exec(interp_prefix, filename, argv+optind, environ, regs, info) != 0) {
 	printf("Error loading %s\n", filename);
 	exit(1);
     }

linux-user/qemu.h

@@ -33,7 +33,8 @@ struct image_info {
 	int		personality;
 };
 
-int elf_exec(const char * filename, char ** argv, char ** envp, 
+int elf_exec(const char *interp_prefix, 
+             const char * filename, char ** argv, char ** envp, 
              struct target_pt_regs * regs, struct image_info *infop);
 
 void target_set_brk(char *new_brk);

opreg_template.h

@@ -1,5 +1,23 @@
-/* templates for various register related operations */
-
+/*
+ *  i386 micro operations (templates for various register related
+ *  operations)
+ * 
+ *  Copyright (c) 2003 Fabrice Bellard
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
 void OPPROTO glue(op_movl_A0,REGNAME)(void)
 {
     A0 = REG;

ops_template.h

@@ -4,21 +4,20 @@
  * 
  *  Copyright (c) 2003 Fabrice Bellard
  *
- *  This program is free software; you can redistribute it and/or modify
- *  it under the terms of the GNU General Public License as published by
- *  the Free Software Foundation; either version 2 of the License, or
- *  (at your option) any later version.
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
  *
- *  This program 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 General Public License for more details.
+ * This 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
+ * Lesser General Public License for more details.
  *
- *  You should have received a copy of the GNU General Public License
- *  along with this program; if not, write to the Free Software
- *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */
-
 #define DATA_BITS (1 << (3 + SHIFT))
 #define SHIFT_MASK (DATA_BITS - 1)
 #define SIGN_MASK (1 << (DATA_BITS - 1))

qemu-doc.texi

@@ -0,0 +1,332 @@
+\input texinfo @c -*- texinfo -*-
+
+@settitle QEMU x86 Emulator Reference Documentation
+@titlepage
+@sp 7
+@center @titlefont{QEMU x86 Emulator Reference Documentation}
+@sp 3
+@end titlepage
+
+@chapter Introduction
+
+QEMU is an x86 processor emulator. Its purpose is to run x86 Linux
+processes on non-x86 Linux architectures such as PowerPC or ARM. By
+using dynamic translation it achieves a reasonnable speed while being
+easy to port on new host CPUs. An obviously interesting x86 only process
+is 'wine' (Windows emulation).
+
+QEMU features:
+
+@itemize 
+
+@item User space only x86 emulator.
+
+@item Currently ported on i386 and PowerPC.
+
+@item Using dynamic translation for reasonnable speed.
+
+@item The virtual x86 CPU supports 16 bit and 32 bit addressing with segmentation. 
+User space LDT and GDT are emulated.
+
+@item Generic Linux system call converter, including most ioctls.
+
+@item clone() emulation using native CPU clone() to use Linux scheduler for threads.
+
+@item Accurate signal handling by remapping host signals to virtual x86 signals.
+
+@item The virtual x86 CPU is a library (@code{libqemu}) which can be used 
+in other projects.
+
+@item An extensive Linux x86 CPU test program is included @file{tests/test-i386}. 
+It can be used to test other x86 virtual CPUs.
+
+@end itemize
+
+Current QEMU Limitations:
+
+@itemize 
+
+@item Not all x86 exceptions are precise (yet). [Very few programs need that].
+
+@item Not self virtualizable (yet). [You cannot launch qemu with qemu on the same CPU].
+
+@item No support for self modifying code (yet). [Very few programs need that, a notable exception is QEMU itself !].
+
+@item No VM86 mode (yet), althought the virtual
+CPU has support for most of it. [VM86 support is useful to launch old 16
+bit DOS programs with dosemu or wine].
+
+@item No SSE/MMX support (yet).
+
+@item No x86-64 support.
+
+@item Some Linux syscalls are missing.
+
+@item The x86 segment limits and access rights are not tested at every 
+memory access (and will never be to have good performances).
+
+@item On non x86 host CPUs, @code{double}s are used instead of the non standard 
+10 byte @code{long double}s of x86 for floating point emulation to get
+maximum performances.
+
+@end itemize
+
+@chapter Invocation
+
+@section Quick Start
+
+In order to launch a Linux process, QEMU needs the process executable
+itself and all the target (x86) dynamic libraries used by it. 
+
+@itemize
+
+@item On x86, you can just try to launch any process by using the native
+libraries:
+
+@example 
+qemu -L / /bin/ls
+@end example
+
+@code{-L /} tells that the x86 dynamic linker must be searched with a
+@file{/} prefix.
+
+
+@item On non x86 CPUs, you need first to download at least an x86 glibc
+(@file{qemu-i386-glibc21.tar.gz} on the QEMU web page). Then you can
+launch the precompiled @file{ls} x86 executable:
+@example
+qemu /usr/local/qemu-i386/bin/ls
+@end example
+You can look at @file{/usr/local/qemu-i386/bin/qemu-conf.sh} so that QEMU is automatically
+launched by the Linux kernel when you try to launch x86 executables. It
+requires the @code{binfmt_misc} module in the Linux kernel.
+
+@end itemize
+
+@section Command line options
+
+@example
+usage: qemu [-h] [-d] [-L path] [-s size] program [arguments...]
+@end example
+
+@table @samp
+@item -h
+Print the help
+@item -d
+Activate log (logfile=/tmp/qemu.log)
+@item -L path   
+Set the x86 elf interpreter prefix (default=/usr/local/qemu-i386)
+@item -s size
+Set the x86 stack size in bytes (default=524288)
+@end table
+
+@chapter QEMU Internals
+
+@section QEMU compared to other emulators
+
+Unlike bochs [3], QEMU emulates only a user space x86 CPU. It means that
+you cannot launch an operating system with it. The benefit is that it is
+simpler and faster due to the fact that some of the low level CPU state
+can be ignored (in particular, no virtual memory needs to be emulated).
+
+Like Valgrind [2], QEMU does user space emulation and dynamic
+translation. Valgrind is mainly a memory debugger while QEMU has no
+support for it (QEMU could be used to detect out of bound memory accesses
+as Valgrind, but it has no support to track uninitialised data as
+Valgrind does). Valgrind dynamic translator generates better code than
+QEMU (in particular it does register allocation) but it is closely tied
+to an x86 host.
+
+EM86 [4] is the closest project to QEMU (and QEMU still uses some of its
+code, in particular the ELF file loader). EM86 was limited to an alpha
+host and used a proprietary and slow interpreter (the interpreter part
+of the FX!32 Digital Win32 code translator [5]).
+
+@section Portable dynamic translation
+
+QEMU is a dynamic translator. When it first encounters a piece of code,
+it converts it to the host instruction set. Usually dynamic translators
+are very complicated and highly CPU dependant. QEMU uses some tricks
+which make it relatively easily portable and simple while achieving good
+performances.
+
+The basic idea is to split every x86 instruction into fewer simpler
+instructions. Each simple instruction is implemented by a piece of C
+code (see @file{op-i386.c}). Then a compile time tool (@file{dyngen})
+takes the corresponding object file (@file{op-i386.o}) to generate a
+dynamic code generator which concatenates the simple instructions to
+build a function (see @file{op-i386.h:dyngen_code()}).
+
+In essence, the process is similar to [1], but more work is done at
+compile time. 
+
+A key idea to get optimal performances is that constant parameters can
+be passed to the simple operations. For that purpose, dummy ELF
+relocations are generated with gcc for each constant parameter. Then,
+the tool (@file{dyngen}) can locate the relocations and generate the
+appriopriate C code to resolve them when building the dynamic code.
+
+That way, QEMU is no more difficult to port than a dynamic linker.
+
+To go even faster, GCC static register variables are used to keep the
+state of the virtual CPU.
+
+@section Register allocation
+
+Since QEMU uses fixed simple instructions, no efficient register
+allocation can be done. However, because RISC CPUs have a lot of
+register, most of the virtual CPU state can be put in registers without
+doing complicated register allocation.
+
+@section Condition code optimisations
+
+Good CPU condition codes emulation (@code{EFLAGS} register on x86) is a
+critical point to get good performances. QEMU uses lazy condition code
+evaluation: instead of computing the condition codes after each x86
+instruction, it store justs one operand (called @code{CC_CRC}), the
+result (called @code{CC_DST}) and the type of operation (called
+@code{CC_OP}).
+
+@code{CC_OP} is almost never explicitely set in the generated code
+because it is known at translation time.
+
+In order to increase performances, a backward pass is performed on the
+generated simple instructions (see
+@code{translate-i386.c:optimize_flags()}). When it can be proved that
+the condition codes are not needed by the next instructions, no
+condition codes are computed at all.
+
+@section Translation CPU state optimisations
+
+The x86 CPU has many internal states which change the way it evaluates
+instructions. In order to achieve a good speed, the translation phase
+considers that some state information of the virtual x86 CPU cannot
+change in it. For example, if the SS, DS and ES segments have a zero
+base, then the translator does not even generate an addition for the
+segment base.
+
+[The FPU stack pointer register is not handled that way yet].
+
+@section Translation cache
+
+A 2MByte cache holds the most recently used translations. For
+simplicity, it is completely flushed when it is full. A translation unit
+contains just a single basic block (a block of x86 instructions
+terminated by a jump or by a virtual CPU state change which the
+translator cannot deduce statically).
+
+[Currently, the translated code is not patched if it jumps to another
+translated code].
+
+@section Exception support
+
+longjmp() is used when an exception such as division by zero is
+encountered. The host SIGSEGV and SIGBUS signal handlers are used to get
+invalid memory accesses. 
+
+[Currently, the virtual CPU cannot retrieve the exact CPU state in some
+exceptions, although it could except for the @code{EFLAGS} register].
+
+@section Linux system call translation
+
+QEMU includes a generic system call translator for Linux. It means that
+the parameters of the system calls can be converted to fix the
+endianness and 32/64 bit issues. The IOCTLs are converted with a generic
+type description system (see @file{ioctls.h} and @file{thunk.c}).
+
+@section Linux signals
+
+Normal and real-time signals are queued along with their information
+(@code{siginfo_t}) as it is done in the Linux kernel. Then an interrupt
+request is done to the virtual CPU. When it is interrupted, one queued
+signal is handled by generating a stack frame in the virtual CPU as the
+Linux kernel does. The @code{sigreturn()} system call is emulated to return
+from the virtual signal handler.
+
+Some signals (such as SIGALRM) directly come from the host. Other
+signals are synthetized from the virtual CPU exceptions such as SIGFPE
+when a division by zero is done (see @code{main.c:cpu_loop()}).
+
+The blocked signal mask is still handled by the host Linux kernel so
+that most signal system calls can be redirected directly to the host
+Linux kernel. Only the @code{sigaction()} and @code{sigreturn()} system
+calls need to be fully emulated (see @file{signal.c}).
+
+@section clone() system call and threads
+
+The Linux clone() system call is usually used to create a thread. QEMU
+uses the host clone() system call so that real host threads are created
+for each emulated thread. One virtual CPU instance is created for each
+thread.
+
+The virtual x86 CPU atomic operations are emulated with a global lock so
+that their semantic is preserved.
+
+@section Bibliography
+
+@table @asis
+
+@item [1] 
+@url{http://citeseer.nj.nec.com/piumarta98optimizing.html}, Optimizing
+direct threaded code by selective inlining (1998) by Ian Piumarta, Fabio
+Riccardi.
+
+@item [2]
+@url{http://developer.kde.org/~sewardj/}, Valgrind, an open-source
+memory debugger for x86-GNU/Linux, by Julian Seward.
+
+@item [3]
+@url{http://bochs.sourceforge.net/}, the Bochs IA-32 Emulator Project,
+by Kevin Lawton et al.
+
+@item [4]
+@url{http://www.cs.rose-hulman.edu/~donaldlf/em86/index.html}, the EM86
+x86 emulator on Alpha-Linux.
+
+@item [5]
+@url{http://www.usenix.org/publications/library/proceedings/usenix-nt97/full_papers/chernoff/chernoff.pdf},
+DIGITAL FX!32: Running 32-Bit x86 Applications on Alpha NT, by Anton
+Chernoff and Ray Hookway.
+
+@end table
+
+@chapter Regression Tests
+
+In the directory @file{tests/}, various interesting x86 testing programs
+are available. There are used for regression testing.
+
+@section @file{hello}
+
+Very simple statically linked x86 program, just to test QEMU during a
+port to a new host CPU.
+
+@section @file{test-i386}
+
+This program executes most of the 16 bit and 32 bit x86 instructions and
+generates a text output. It can be compared with the output obtained with
+a real CPU or another emulator. The target @code{make test} runs this
+program and a @code{diff} on the generated output.
+
+The Linux system call @code{modify_ldt()} is used to create x86 selectors
+to test some 16 bit addressing and 32 bit with segmentation cases.
+
+@section @file{testsig}
+
+This program tests various signal cases, including SIGFPE, SIGSEGV and
+SIGILL.
+
+@section @file{testclone}
+
+Tests the @code{clone()} system call (basic test).
+
+@section @file{testthread}
+
+Tests the glibc threads (more complicated than @code{clone()} because signals
+are also used).
+
+@section @file{sha1}
+
+It is a simple benchmark. Care must be taken to interpret the results
+because it mostly tests the ability of the virtual CPU to optimize the
+@code{rol} x86 instruction and the condition code computations.
+

tests/Makefile

@@ -28,7 +28,7 @@ testthread: testthread.c
 # i386 emulation test (test various opcodes) */
 test-i386: test-i386.c test-i386-code16.S \
            test-i386.h test-i386-shift.h test-i386-muldiv.h
-	$(CC) $(CFLAGS) $(LDFLAGS) -static -o $@ test-i386.c test-i386-code16.S -lm
+	$(CC) $(CFLAGS) $(LDFLAGS) -o $@ test-i386.c test-i386-code16.S -lm
 
 test: test-i386
 ifeq ($(ARCH),i386)

tests/testsig.c

@@ -15,21 +15,34 @@ void alarm_handler(int sig)
     alarm(1);
 }
 
+#ifndef REG_EAX
+#define REG_EAX EAX
+#define REG_EBX EBX
+#define REG_ECX ECX
+#define REG_EDX EDX
+#define REG_ESI ESI
+#define REG_EDI EDI
+#define REG_EBP EBP
+#define REG_ESP ESP
+#define REG_EIP EIP
+#define REG_EFL EFL
+#endif
+
 void dump_regs(struct ucontext *uc)
 {
     printf("EAX=%08x EBX=%08x ECX=%08x EDX=%08x\n"
            "ESI=%08x EDI=%08x EBP=%08x ESP=%08x\n"
            "EFL=%08x EIP=%08x\n",
-           uc->uc_mcontext.gregs[EAX],
-           uc->uc_mcontext.gregs[EBX],
-           uc->uc_mcontext.gregs[ECX],
-           uc->uc_mcontext.gregs[EDX],
-           uc->uc_mcontext.gregs[ESI],
-           uc->uc_mcontext.gregs[EDI],
-           uc->uc_mcontext.gregs[EBP],
-           uc->uc_mcontext.gregs[ESP],
-           uc->uc_mcontext.gregs[EFL],
-           uc->uc_mcontext.gregs[EIP]);
+           uc->uc_mcontext.gregs[REG_EAX],
+           uc->uc_mcontext.gregs[REG_EBX],
+           uc->uc_mcontext.gregs[REG_ECX],
+           uc->uc_mcontext.gregs[REG_EDX],
+           uc->uc_mcontext.gregs[REG_ESI],
+           uc->uc_mcontext.gregs[REG_EDI],
+           uc->uc_mcontext.gregs[REG_EBP],
+           uc->uc_mcontext.gregs[REG_ESP],
+           uc->uc_mcontext.gregs[REG_EFL],
+           uc->uc_mcontext.gregs[REG_EIP]);
 }
 
 void sig_handler(int sig, siginfo_t *info, void *puc)