commit 1cc215aaf92a6cf3cea436f2c215a84839fd59bc
from: rsc <devnull@localhost>
date: Sat Dec 25 22:03:28 2004 UTC

better unwinding for 386.

command-line extraction from core files on linux and freebsd.

move linux ureg into ureg386.h (used in many places).

commit - cdf1805191ba4ab5b8fbb1697a95fe0d32e25ee6
commit + 1cc215aaf92a6cf3cea436f2c215a84839fd59bc
blob - 12b0f9b8001beaab242e039df8d44cd04621f0fa
blob + def8925e1547fcd098a64a4e6dafe0676c6d5927
--- src/libmach/Linux.c
+++ src/libmach/Linux.c
@@ -18,10 +18,12 @@
 #include <sys/ptrace.h>
 #include <sys/types.h>
 #include <sys/wait.h>
+#include <sys/procfs.h>
 #include <signal.h>
 #include <errno.h>
 #include <libc.h>
 #include <mach.h>
+#include <elf.h>
 #include "ureg386.h"
 
 Mach *machcpu = &mach386;
@@ -34,42 +36,27 @@ struct PtraceRegs
 	int pid;
 };
 
-static int ptracerw(Map*, Seg*, ulong, void*, uint, int);
+static int ptracesegrw(Map*, Seg*, ulong, void*, uint, int);
 static int ptraceregrw(Regs*, char*, ulong*, int);
 
 static int attachedpids[1000];
 static int nattached;
 
-void
-unmapproc(Map *map)
-{
-	int i;
-
-	if(map == nil)
-		return;
-	for(i=0; i<map->nseg; i++)
-		while(i<map->nseg && map->seg[i].pid){
-			map->nseg--;
-			memmove(&map->seg[i], &map->seg[i+1], 
-				(map->nseg-i)*sizeof(map->seg[0]));
-		}
-}
-
 int
-mapproc(int pid, Map *map, Regs **rp)
+ptraceattach(int pid)
 {
 	int i;
-	Seg s;
-	PtraceRegs *r;
 
+	/*
 	if(nattached==1 && attachedpids[0] == pid)
 		goto already;
 	if(nattached)
 		detachproc(attachedpids[0]);
-
+	*/
+	
 	for(i=0; i<nattached; i++)
 		if(attachedpids[i]==pid)
-			goto already;
+			return 0;
 	if(nattached == nelem(attachedpids)){
 		werrstr("attached to too many processes");
 		return -1;
@@ -86,15 +73,42 @@ mapproc(int pid, Map *map, Regs **rp)
 		return -1;
 	}
 	attachedpids[nattached++] = pid;
+	return 0;
+}
 
-already:
+void
+unmapproc(Map *map)
+{
+	int i;
+
+	if(map == nil)
+		return;
+	for(i=0; i<map->nseg; i++)
+		while(i<map->nseg && map->seg[i].pid){
+			map->nseg--;
+			memmove(&map->seg[i], &map->seg[i+1], 
+				(map->nseg-i)*sizeof(map->seg[0]));
+		}
+}
+
+
+
+int
+mapproc(int pid, Map *map, Regs **rp)
+{
+	Seg s;
+	PtraceRegs *r;
+
+	if(ptraceattach(pid) < 0)
+		return -1;
+
 	memset(&s, 0, sizeof s);
 	s.base = 0;
 	s.size = 0xFFFFFFFF;
 	s.offset = 0;
 	s.name = "data";
 	s.file = nil;
-	s.rw = ptracerw;
+	s.rw = ptracesegrw;
 	s.pid = pid;
 	if(addseg(map, s) < 0){
 		fprint(2, "addseg: %r\n");
@@ -126,17 +140,16 @@ detachproc(int pid)
 }
 
 static int
-ptracerw(Map *map, Seg *seg, ulong addr, void *v, uint n, int isr)
+ptracerw(int type, int xtype, int isr, int pid, ulong addr, void *v, uint n)
 {
 	int i;
 	u32int u;
 	uchar buf[4];
 
-	addr += seg->base;
 	for(i=0; i<n; i+=4){
 		if(isr){
 			errno = 0;
-			u = ptrace(PTRACE_PEEKDATA, seg->pid, addr+i, 0);
+			u = ptrace(type, pid, addr+i, 0);
 			if(errno)
 				goto ptraceerr;
 			if(n-i >= 4)
@@ -150,14 +163,14 @@ ptracerw(Map *map, Seg *seg, ulong addr, void *v, uint
 				u = *(u32int*)((char*)v+i);
 			else{
 				errno = 0;
-				u = ptrace(PTRACE_PEEKDATA, seg->pid, addr+i, 0);
+				u = ptrace(xtype, pid, addr+i, 0);
 				if(errno)
 					return -1;
 				*(u32int*)buf = u;
 				memmove(buf, (char*)v+i, n-i);
 				u = *(u32int*)buf;
 			}
-			if(ptrace(PTRACE_POKEDATA, seg->pid, addr+i, &u) < 0)
+			if(ptrace(type, pid, addr+i, &u) < 0)
 				goto ptraceerr;
 		}
 	}
@@ -166,6 +179,14 @@ ptracerw(Map *map, Seg *seg, ulong addr, void *v, uint
 ptraceerr:
 	werrstr("ptrace: %r");
 	return -1;
+}
+
+static int
+ptracesegrw(Map *map, Seg *seg, ulong addr, void *v, uint n, int isr)
+{
+	addr += seg->base;
+	return ptracerw(isr ? PTRACE_PEEKDATA : PTRACE_POKEDATA, PTRACE_PEEKDATA,
+		isr, seg->pid, addr, v, n);
 }
 
 static char* linuxregs[] = {
@@ -482,4 +503,192 @@ proctextfile(int pid)
 	}
 	Bterm(b);
 #endif
+
+/*
+ * bottom-end functions for libthread_db to call
+ */
+enum
+{
+	PS_OK,
+	PS_ERR,
+	PS_BADPID,
+	PS_BADLWPID,
+	PS_BADADDR,
+	PS_NOSYM,
+	PS_NOFPREGS,
+};
 
+pid_t
+ps_getpid(struct ps_prochandle *ph)
+{
+	return ph->pid;
+}
+
+int
+ps_pstop(const struct ps_prochandle *ph)
+{
+	return PS_ERR;
+}
+
+int
+ps_pcontinue(const struct ps_prochandle *ph)
+{
+	return PS_ERR;
+}
+
+int
+ps_lstop(const struct ps_prochandle *ph)
+{
+	return PS_ERR;
+}
+
+int
+ps_lcontinue(const struct ps_prochandle *ph)
+{
+	return PS_ERR;
+}
+
+/* read/write data or text memory */
+int
+ps_pdread(struct ps_prochandle *ph, psaddr_t addr, void *v, size_t sz)
+{
+//print("read %d %p %d\n", ph->pid, addr, sz);
+	if(ptracerw(PTRACE_PEEKDATA, 0, 1, ph->pid, (ulong)addr, v, sz) < 0)
+		return PS_ERR;
+//print("	=> 0x%lux\n", *(ulong*)v);
+	return PS_OK;
+}
+
+int
+ps_pdwrite(struct ps_prochandle *ph, psaddr_t addr, void *v, size_t sz)
+{
+//print("write %d %p\n", ph->pid, addr);
+	if(ptracerw(PTRACE_POKEDATA, PTRACE_PEEKDATA, 0, ph->pid, (ulong)addr, v, sz) < 0)
+		return PS_ERR;
+	return PS_OK;
+}
+
+int
+ps_ptread(struct ps_prochandle *ph, psaddr_t addr, void *v, size_t sz)
+{
+//print("read %d %p\n", ph->pid, addr);
+	if(ptracerw(PTRACE_PEEKTEXT, 0, 1, ph->pid, (ulong)addr, v, sz) < 0)
+		return PS_ERR;
+	return PS_OK;
+}
+
+int
+ps_ptwrite(struct ps_prochandle *ph, psaddr_t addr, void *v, size_t sz)
+{
+//print("write %d %p\n", ph->pid, addr);
+	if(ptracerw(PTRACE_POKETEXT, PTRACE_PEEKTEXT, 0, ph->pid, (ulong)addr, v, sz) < 0)
+		return PS_ERR;
+	return PS_OK;
+}
+
+int
+ps_lgetregs(struct ps_prochandle *ph, lwpid_t lwp, prgregset_t regs)
+{
+	if(lwp == 0){
+		memset(regs, 0xfe, sizeof(regs[0])*nelem(linuxregs));
+		return PS_OK;
+	}
+//print("getregs %d %p (%d)\n", lwp, regs, sizeof(regs[0])*nelem(linuxregs));
+	
+	if(ptraceattach(lwp) < 0){
+		fprint(2, "ptrace attach: %r\n");
+		return PS_ERR;
+	}
+
+	if(ptracerw(PTRACE_PEEKUSER, 0, 1, lwp, 0, regs, sizeof(regs[0])*nelem(linuxregs)) < 0){
+		fprint(2, "ptrace: %r\n");
+		return PS_ERR;
+	}
+	return PS_OK;
+}
+
+int
+ps_lsetregs(struct ps_prochandle *ph, lwpid_t lwp, prgregset_t regs)
+{
+print("setregs %d\n", lwp);
+	if(ptracerw(PTRACE_POKEUSER, PTRACE_PEEKUSER, 1, lwp, 0, regs, sizeof(regs[0])*nelem(linuxregs)) < 0)
+		return PS_ERR;
+	return PS_OK;
+}
+
+int
+ps_lgetfpregs(struct ps_prochandle *ph, lwpid_t lwp, prfpregset_t *fpregs)
+{
+	if(ptracerw(PTRACE_PEEKUSER, 0, 1, lwp, 18*4, fpregs, sizeof *fpregs) < 0)
+		return PS_ERR;
+	return PS_OK;
+}
+
+int
+ps_lsetfpregs(struct ps_prochandle *ph, lwpid_t lwp, prfpregset_t *fpregs)
+{
+	if(ptracerw(PTRACE_POKEUSER, PTRACE_PEEKUSER, 1, lwp, 18*4, fpregs, sizeof *fpregs) < 0)
+		return PS_ERR;
+	return PS_OK;
+}
+
+/* Fetch the special per-thread address associated with the given LWP.
+   This call is only used on a few platforms (most use a normal register).
+   The meaning of the `int' parameter is machine-dependent.  */
+int
+ps_get_thread_area(struct ps_prochandle *ph, lwpid_t lwp, int xxx, psaddr_t *addr)
+{
+	return PS_NOSYM;
+}
+
+/* Look up the named symbol in the named DSO in the symbol tables
+   associated with the process being debugged, filling in *SYM_ADDR
+   with the corresponding run-time address.  */
+int
+ps_pglobal_lookup(struct ps_prochandle *ph, char *object_name, char *sym_name, psaddr_t *sym_addr)
+{
+	Fhdr *fp;
+	ulong addr;
+
+	if((fp = findhdr(object_name)) == nil){
+print("lookup %d %s %s => no such hdr\n", ph->pid, object_name, sym_name);
+		return PS_NOSYM;
+	}
+	if(elfsymlookup(fp->elf, sym_name, &addr) < 0){
+print("lookup %d %s %s => name not found\n", ph->pid, object_name, sym_name);
+		return PS_NOSYM;
+	}
+print("lookup %d %s %s => 0x%lux\n", ph->pid, object_name, sym_name, addr);
+	*sym_addr = (void*)(addr+fp->base);
+	return PS_OK;
+}
+
+Ureg*
+_linux2ureg386(UregLinux386 *l)
+{
+	Ureg *u;
+
+	u = malloc(sizeof(Ureg));
+	if(u == nil)
+		return nil;
+	u->di = l->edi;
+	u->si = l->esi;
+	u->bp = l->ebp;
+	u->nsp = l->esp;
+	u->bx = l->ebx;
+	u->dx = l->edx;
+	u->cx = l->ecx;
+	u->ax = l->eax;
+	u->gs = l->xgs;
+	u->fs = l->xfs;
+	u->es = l->xes;
+	u->ds = l->xds;
+	u->trap = ~0; // l->trapno;
+	u->ecode = ~0; // l->err;
+	u->pc = l->eip;
+	u->cs = l->xcs;
+	u->flags = l->eflags;
+	u->sp = l->esp;
+	u->ss = l->xss;
+	return u;
+}
blob - eb99947d39856eeb2615a1ab24598b12ef15ab1a
blob + f0f84230d5f12fe9079992ccb13f695fc7c84196
--- src/libmach/crackelf.c
+++ src/libmach/crackelf.c
@@ -40,11 +40,18 @@ static struct
 	uint mtype;
 	uint atype;
 	int (*coreregs)(Elf*, ElfNote*, uchar**);
+	int (*corecmd)(Elf*, ElfNote*, char**);
 } ctab[] = 
 {	/* Font Tab 4 */
-	M386,		ALINUX,		coreregslinux386,
-	M386,		ANONE,		coreregslinux386,	/* [sic] */
-	M386,		AFREEBSD,	coreregsfreebsd386,
+	M386,		ALINUX,
+		coreregslinux386,
+		corecmdlinux386,
+	M386,		ANONE,
+		coreregslinux386,	/* [sic] */
+		corecmdlinux386,	/* [sic] */
+	M386,		AFREEBSD,
+		coreregsfreebsd386,
+		corecmdfreebsd386,
 };
 
 int
blob - 6ed239bc2ce4ba9d2d6ccdfa51a296832423182d
blob + d4b459e1cc431dae80736d89c347d0f7f7c3084c
--- src/libmach/elf.h
+++ src/libmach/elf.h
@@ -218,6 +218,7 @@ struct Elf
 	ElfSect	*dynsym;
 	ElfSect	*dynstr;
 	ElfSect	*bss;
+	ulong	dynamic;		/* offset to elf dynamic crap */
 
 	int		(*coreregs)(Elf*, ElfNote*, uchar**);
 };
@@ -227,7 +228,10 @@ Elf*	elfinit(int);
 ElfSect *elfsection(Elf*, char*);
 void	elfclose(Elf*);
 int	elfsym(Elf*, int, ElfSym*);
+int	elfsymlookup(Elf*, char*, ulong*);
 int	elfmap(Elf*, ElfSect*);
 
 int	coreregslinux386(Elf*, ElfNote*, uchar**);
 int	coreregsfreebsd386(Elf*, ElfNote*, uchar**);
+int	corecmdlinux386(Elf*, ElfNote*, char**);
+int	corecmdfreebsd386(Elf*, ElfNote*, char**);
blob - 2ff746dee42843fa39c6604fb527172662975961
blob + 84f6c0fd18e153e34f3f95a99b4e4621baaf33dd
--- src/libmach/elfcorefreebsd386.c
+++ src/libmach/elfcorefreebsd386.c
@@ -6,6 +6,7 @@
 
 typedef struct Lreg Lreg;
 typedef struct Status Status;
+typedef struct Psinfo Psinfo;
 
 struct Lreg
 {
@@ -32,16 +33,24 @@ struct Lreg
 
 struct Status
 {
-    u32int		version;	/* Version number of struct (1) */
-    u32int		statussz;	/* sizeof(prstatus_t) (1) */
-    u32int		gregsetsz;	/* sizeof(gregset_t) (1) */
-    u32int		fpregsetsz;	/* sizeof(fpregset_t) (1) */
-    u32int		osreldate;	/* Kernel version (1) */
-    u32int		cursig;	/* Current signal (1) */
-    u32int		pid;		/* Process ID (1) */
-    Lreg		reg;		/* General purpose registers (1) */
+	u32int		version;	/* Version number of struct (1) */
+	u32int		statussz;	/* sizeof(prstatus_t) (1) */
+	u32int		gregsetsz;	/* sizeof(gregset_t) (1) */
+	u32int		fpregsetsz;	/* sizeof(fpregset_t) (1) */
+	u32int		osreldate;	/* Kernel version (1) */
+	u32int		cursig;	/* Current signal (1) */
+	u32int		pid;		/* Process ID (1) */
+	Lreg		reg;		/* General purpose registers (1) */
 };
 
+struct Psinfo
+{
+	u32int	version;
+	u32int	size;
+	char	name[17];
+	char	psargs[81];
+};
+
 int
 coreregsfreebsd386(Elf *elf, ElfNote *note, uchar **up)
 {
@@ -87,3 +96,25 @@ coreregsfreebsd386(Elf *elf, ElfNote *note, uchar **up
 	return sizeof(Ureg);
 }
 
+int
+corecmdfreebsd386(Elf *elf, ElfNote *note, char **pp)
+{
+	char *t;
+	Psinfo *p;
+
+	*pp = nil;
+	if(note->descsz < sizeof(Psinfo)){
+		werrstr("elf psinfo note too small");
+		return -1;
+	}
+	p = (Psinfo*)note->desc;
+	print("elf name %s\nelf args %s\n", p->name, p->psargs);
+	t = malloc(80+1);
+	if(t == nil)
+		return -1;
+	memmove(t, p->psargs, 80);
+	t[80] = 0;
+	*pp = t;
+	return 0;
+}
+
blob - f6a0234c64263db6aa4e2d6497d4b503a8a4c91b
blob + 18f8bdfec0bb7e3f6e11501f90762e15325ba039
--- src/libmach/elfcorelinux386.c
+++ src/libmach/elfcorelinux386.c
@@ -6,30 +6,10 @@
 
 typedef struct Lreg Lreg;
 typedef struct Status Status;
+typedef struct Psinfo Psinfo;
 
-struct Lreg
-{
-	u32int	ebx;
-	u32int	ecx;
-	u32int	edx;
-	u32int	esi;
-	u32int	edi;
-	u32int	ebp;
-	u32int	eax;
-	u32int	ds;
-	u32int	es;
-	u32int	fs;
-	u32int	gs;
-	u32int	origeax;
-	u32int	eip;
-	u32int	cs;
-	u32int	eflags;
-	u32int	esp;
-	u32int	ss;
-};
-
 /*
- * Lreg is 64-bit aligned within status, so we shouldn't 
+ * UregLinux386 is 64-bit aligned within status, so we shouldn't 
  * have any packing problems. 
  */
 struct Status
@@ -48,15 +28,32 @@ struct Status
 	u32int	stime[2];
 	u32int	cutime[2];
 	u32int	cstime[2];
-	Lreg	reg;
+	UregLinux386	reg;
 	u32int	fpvalid;
 };
 
+struct Psinfo
+{
+	char state;
+	char sname;
+	char zomb;
+	char nice;
+	u32int flag;
+	u16int uid;
+	u16int gid;
+	u32int pid;
+	u32int ppid;
+	u32int pgrp;
+	u32int sid;
+	char fname[16];
+	char psargs[80];
+};
+
 int
 coreregslinux386(Elf *elf, ElfNote *note, uchar **up)
 {
 	Status *s;
-	Lreg *l;
+	UregLinux386 *l;
 	Ureg *u;
 
 	if(note->descsz < sizeof(Status)){
@@ -65,31 +62,31 @@ coreregslinux386(Elf *elf, ElfNote *note, uchar **up)
 	}
 	s = (Status*)note->desc;
 	l = &s->reg;
-	u = malloc(sizeof(Ureg));
-	if(u == nil)
+	if((u = _linux2ureg386(l)) == nil)
 		return -1;
-
-	/* no byte order problems - just copying and rearranging */
-	u->di = l->edi;
-	u->si = l->esi;
-	u->bp = l->ebp;
-	u->nsp = l->esp;
-	u->bx = l->ebx;
-	u->dx = l->edx;
-	u->cx = l->ecx;
-	u->ax = l->eax;
-	u->gs = l->gs;
-	u->fs = l->fs;
-	u->es = l->es;
-	u->ds = l->ds;
-	u->trap = ~0; // l->trapno;
-	u->ecode = ~0; // l->err;
-	u->pc = l->eip;
-	u->cs = l->cs;
-	u->flags = l->eflags;
-	u->sp = l->esp;
-	u->ss = l->ss;
 	*up = (uchar*)u;
 	return sizeof(Ureg);
 }
 
+int
+corecmdlinux386(Elf *elf, ElfNote *note, char **pp)
+{
+	char *t;
+	Psinfo *p;
+
+	*pp = nil;
+	if(note->descsz < sizeof(Psinfo)){
+		werrstr("elf psinfo note too small");
+		return -1;
+	}
+	p = (Psinfo*)note->desc;
+	print("elf name %s\nelf args %s\n", p->fname, p->psargs);
+	t = malloc(80+1);
+	if(t == nil)
+		return -1;
+	memmove(t, p->psargs, 80);
+	t[80] = 0;
+	*pp = t;
+	return 0;
+}
+
blob - 6e4485190b3a7eb03a4f5101a7c7870ce00dc7cc
blob + 035c6a5233802ed23e254628f3811337d85dc95f
--- src/libmach/frame.c
+++ src/libmach/frame.c
@@ -79,7 +79,7 @@ stacktrace(Map *map, Regs *regs, Tracer trace)
 		lr.oldregs = regs;
 		lr.val = cur;
 		lr.map = map;
-		if((i = unwindframe(map, &lr.r, next)) >= 0)
+		if((i = unwindframe(map, &lr.r, next, sp)) >= 0)
 			nextpc = next[ipc];
 		else
 			nextpc = ~(ulong)0;
blob - 4b43683e654654cae5f0c6e4031d535d6413faee
blob + b47fcd554adae8f174a0ea4fe6a211fbb3d42be5
--- src/libmach/mach386.c
+++ src/libmach/mach386.c
@@ -29,7 +29,7 @@ static	int	i386hexinst(Map*, ulong, char*, int);
 static	int	i386das(Map*, ulong, char, char*, int);
 static	int	i386instlen(Map*, ulong);
 static	char	*i386windregs[];
-static	int	i386unwind(Map*, Regs*, ulong*);
+static	int	i386unwind(Map*, Regs*, ulong*, Symbol*);
 
 static	Regdesc i386reglist[] = {
 	{"DI",		REGOFF(di),	RINT, 'X'},
@@ -128,14 +128,37 @@ static char *i386windregs[] = {
 	0,
 };
 
+/*
+ * The wrapper code around Linux system calls 
+ * saves AX on the stack before calling some calls
+ * (at least, __libc_nanosleep), when running in 
+ * threaded programs. 
+ */
+static void
+syscallhack(Map *map, Regs *regs, int *spoff)
+{
+	ulong pc;
+	char buf[60];
+
+	rget(regs, "PC", &pc);
+	if(i386das(map, pc-2, 0, buf, sizeof buf) != 2 || strncmp(buf, "INTB\t$", 6) != 0)
+		return;
+	if(i386das(map, pc, 0, buf, sizeof buf) != 2 || strcmp(buf, "MOVL\tDX,BX") != 0)
+		return;
+	if(i386das(map, pc+2, 0, buf, sizeof buf) != 3 || strcmp(buf, "XCHGL\tAX,0(SP)") != 0)
+		return;
+	*spoff += 4;	
+}
+
 static int
-i386unwind(Map *map, Regs *regs, ulong *next)
+i386unwind(Map *map, Regs *regs, ulong *next, Symbol *sym)
 {
-	int isp, ipc, ibp;
-	ulong bp;
+	int i, isp, ipc, ibp, havebp, n, spoff, off[9];
+	ulong pc;
 	u32int v;
+	char buf[60], *p;
 
-	/* No symbol information, use frame pointer and do the best we can. */
+//print("i386unwind %s\n", sym ? sym->name : nil);
 	isp = windindex("SP");
 	ipc = windindex("PC");
 	ibp = windindex("BP");
@@ -144,19 +167,85 @@ i386unwind(Map *map, Regs *regs, ulong *next)
 		return -1;
 	}
 
-	bp = next[ibp];
+	/*
+	 * Disassemble entry to figure out
+	 * where values have been saved.
+	 * Perhaps should disassemble exit path
+	 * instead -- a random walk on the code
+	 * should suffice to get us to a RET.
+	 */
+	if(sym){
+		pc = sym->loc.addr;
+//print("startpc %lux\n", pc);
+		memset(off, 0xff, sizeof off);
+		spoff = 0;
+		havebp = 0;
+		for(;;){
+			if((n = i386das(map, pc, 0, buf, sizeof buf)) < 0)
+				break;
+//print("%s\n", buf);
+			pc += n;
+			if(strncmp(buf, "PUSHL\t", 6) == 0){
+				spoff += 4;
+				if((i = windindex(buf+6)) >= 0)
+					off[i] = spoff;
+			}else if(strcmp(buf, "MOVL\tSP,BP") == 0 && spoff == 4 && off[ibp] == 4){
+				havebp = 1;
+			}else if(strncmp(buf, "SUBL\t$", 6) == 0){
+				if((p = strrchr(buf, ',')) && strcmp(p, ",SP") == 0){
+//print("spoff %s\n", buf+6);
+					spoff += strtol(buf+6, 0, 16);
+				}
+				break;
+			}else if(strncmp(buf, "XORL\t", 5) == 0 || strncmp(buf, "MOVL\t", 5) == 0){
+				/*
+				 * Hope these are rescheduled non-prologue instructions
+				 * like XORL AX, AX or MOVL $0x3, AX and thus ignorable.
+				 */
+			}else
+				break;
+		}
 
-	if(get4(map, bp, &v) < 0)
-		return -1;
-	next[ibp] = v;
+		syscallhack(map, regs, &spoff);
 
-	next[isp] = bp+4;
+		if(havebp){
+//print("havebp\n");
+			rget(regs, "BP", &next[isp]);
+			get4(map, next[isp], &v);
+			next[ibp] = v;
+			next[isp] += 4;
+		}else{
+			rget(regs, "SP", &next[isp]);
+//print("old sp %lux + %d\n", next[isp], spoff);
+			next[isp] += spoff;
+		}
+		for(i=0; i<nelem(off); i++)
+			if(off[i] != -1){
+				get4(map, next[isp]-off[i], &v);
+				next[i] = v;
+			}
 
-	if(get4(map, bp+4, &v) < 0)
+		if(get4(map, next[isp], &v) < 0)
+			return -1;
+//print("new pc %lux => %lux\n", next[isp], v);
+		next[ipc] = v;
+		next[isp] += 4;
+		return 0;
+	}
+
+	/*
+	 * Rely on bp chaining
+	 */
+	if(rget(regs, "BP", &next[isp]) < 0
+	|| get4(map, next[isp], &v) < 0)
 		return -1;
+	next[ibp] = v;
+	next[isp] += 4;
+	if(get4(map, next[isp], &v) < 0)
+		return -1;
 	next[ipc] = v;
-
-	return 0;	
+	next[isp] += 4;
+	return 0;
 }
 
 //static	char	STARTSYM[] =	"_main";
@@ -1766,8 +1855,10 @@ pea(Instr *ip)
 	else {
 		if (ip->base < 0)
 			immediate(ip, ip->disp);
-		else
+		else {
+			bprint(ip, "%lux", ip->disp);
 			bprint(ip,"(%s%s)", ANAME(ip), reg[(uchar)ip->base]);
+		}
 	}
 	if (ip->index >= 0)
 		bprint(ip,"(%s%s*%d)", ANAME(ip), reg[(uchar)ip->index], 1<<ip->ss);
blob - c704be7f1d96b1af9bc13f437eab5d2c8fc51a45
blob + 6191721639fbfad9683a44d0560f4ed7b2e7e8e4
--- src/libmach/machpower.c
+++ src/libmach/machpower.c
@@ -1337,7 +1337,7 @@ static char *powerwindregs[] = 
 };
 
 static int
-powerunwind(Map *map, Regs *regs, ulong *next)
+powerunwind(Map *map, Regs *regs, ulong *next, Symbol *sym)
 {
 	/*
 	 * This is tremendously hard.  The best we're going to
blob - 77426436b9b0feb7b5961250416458ffaba7cdef
blob + 8ebe03744e10597c62416a480943723755fe956e
--- src/libmach/mkfile
+++ src/libmach/mkfile
@@ -4,6 +4,7 @@ LIB=libmach.a
 
 OFILES=\
 	$SYSNAME.$O\
+	cmdline.$O\
 	crack.$O\
 	crackelf.$O\
 	crackmacho.$O\
@@ -17,6 +18,7 @@ OFILES=\
 	dwarfpc.$O\
 	dwarfpubnames.$O\
 	elf.$O\
+	elfdl386.$O\
 	elfcorefreebsd386.$O\
 	elfcorelinux386.$O\
 	frame.$O\
@@ -57,6 +59,13 @@ dwarfdump: dwarfdump.o $LIBDIR/$LIB
 nm: nm.o $LIBDIR/$LIB
 	$LD -o $target $prereq -l9
 
+t: t.o $LIBDIR/$LIB
+	$LD -o $target $prereq -l9 -lthread_db
+
+elfnm: elfnm.o $LIBDIR/$LIB
+	$LD -o $target $prereq -l9
+
+
 SunOS.$O: nosys.c
 Darwin.$O: nosys.c
 OpenBSD.$O: nosys.c
blob - b734957f39c3d05b35e9336e1106f95565a06b9d
blob + a5cf0314116b2122a7f5b1a30e1c65f27824f14a
--- src/libmach/sym.c
+++ src/libmach/sym.c
@@ -50,6 +50,23 @@ _delhdr(Fhdr *h)
 	h->next = nil;
 }
 
+Fhdr*
+findhdr(char *name)
+{
+	int len, plen;
+	Fhdr *p;
+
+	len = strlen(name);
+	for(p=fhdrlist; p; p=p->next){
+		plen = strlen(p->filename);
+		if(plen >= len)
+		if(strcmp(p->filename+plen-len, name) == 0)
+		if(plen == len || p->filename[plen-len-1] == '/')
+			return p;
+	}
+	return nil;
+}
+
 int
 pc2file(ulong pc, char *file, uint nfile, ulong *line)
 {
@@ -354,14 +371,14 @@ findlsym(Symbol *s1, Loc loc, Symbol *s2)
 }
 
 int
-unwindframe(Map *map, Regs *regs, ulong *next)
+unwindframe(Map *map, Regs *regs, ulong *next, Symbol *sym)
 {
 	Fhdr *p;
 
 	for(p=fhdrlist; p; p=p->next)
-		if(p->unwind && p->unwind(p, map, regs, next) >= 0)
+		if(p->unwind && p->unwind(p, map, regs, next, sym) >= 0)
 			return 0;
-	if(mach->unwind && mach->unwind(map, regs, next) >= 0)
+	if(mach->unwind && mach->unwind(map, regs, next, sym) >= 0)
 		return 0;
 	return -1;
 }
blob - eeafa8dccb8bc755aac55f482ffa3ab7242e896b
blob + 3ac1257759627739c2cfeedab87f45bd82d4fb02
--- src/libmach/symdwarf.c
+++ src/libmach/symdwarf.c
@@ -13,7 +13,7 @@ static int	dwarfindexlsym(Fhdr*, Symbol*, uint, Symbol
 static int	dwarffindlsym(Fhdr*, Symbol*, Loc, Symbol*);
 static void	dwarfsyminit(Fhdr*);
 static int	dwarftosym(Fhdr*, Dwarf*, DwarfSym*, Symbol*, int);
-static int	_dwarfunwind(Fhdr *fhdr, Map *map, Regs *regs, ulong *next);
+static int	_dwarfunwind(Fhdr *fhdr, Map *map, Regs *regs, ulong *next, Symbol*);
 
 int
 symdwarf(Fhdr *hdr)
@@ -396,7 +396,7 @@ dwarfexprfmt(Fmt *fmt)
 #endif
 
 static int
-_dwarfunwind(Fhdr *fhdr, Map *map, Regs *regs, ulong *next)
+_dwarfunwind(Fhdr *fhdr, Map *map, Regs *regs, ulong *next, Symbol *sym)
 {
 	char *name;
 	int i, j;
blob - 7babbd496997724635fa29c7c29951b6a8e26eb5
blob + 0b9f410e1c85e7817f709ed5c0731b115a93b8f0
--- src/libmach/symelf.c
+++ src/libmach/symelf.c
@@ -53,6 +53,7 @@ elfsyminit(Fhdr *fp)
 		p = &elf->prog[i];
 		if(p->type != ElfProgDynamic)
 			continue;
+		elf->dynamic = p->vaddr;
 		memset(&sym, 0, sizeof sym);
 		sym.name = "_DYNAMIC";
 		sym.loc = locaddr(p->vaddr);
@@ -65,6 +66,23 @@ elfsyminit(Fhdr *fp)
 }
 
 int
+elfsymlookup(Elf *elf, char *name, ulong *addr)
+{
+	int i;
+	ElfSym esym;
+
+	for(i=0; elfsym(elf, i, &esym) >= 0; i++){
+		if(esym.name == nil)
+			continue;
+		if(strcmp(esym.name, name) == 0){
+			*addr = esym.value;
+			return 0;
+		}
+	}
+	return -1;
+}
+
+int
 symelf(Fhdr *fhdr)
 {
 	int ret;
blob - 961ef6d093d7b18d1c04e721dfdfbde3294a6c72
blob + f5f9a474adf261869b609e0e1013ebc71ddd3c10
--- src/libmach/ureg386.h
+++ src/libmach/ureg386.h
@@ -29,6 +29,7 @@ struct UregLinux386
 	ulong	ecx;
 	ulong	edx;
 	ulong	esi;
+	ulong	edi;
 	ulong	ebp;
 	ulong	eax;
 	ulong	xds;
@@ -43,3 +44,5 @@ struct UregLinux386
 	ulong	xss;
 };
 
+Ureg *_linux2ureg386(UregLinux386*);
+