static int _dwarfnametounit(Dwarf *d, char *name, DwarfBlock *bl, DwarfSym *s) { int vers; ulong len, unit, off; uchar *next; char *str; DwarfBuf b; b.d = d; b.p = bl->data; b.ep = b.p + bl->len; while(b.p < b.ep){ len = dwarfget4(&b); if(len > b.ep-b.p){ werrstr("bad length in dwarf name header"); return -1; } next = b.p + len; vers = dwarfget2(&b); if(vers != 1 && vers != 2){ werrstr("bad version %d in dwarf name header", vers); return -1; } unit = dwarfget4(&b); dwarfget4(&b); /* unit length */ while(b.p < next){ off = dwarfget4(&b); if(off == 0) break; str = dwarfgetstring(&b); if(strcmp(str, name) == 0){ if(dwarfenumunit(d, unit, s) < 0) return -1; if(unit + off >= s->b.ep - d->info.data){ werrstr("bad offset in name entry"); return -1; } s->b.p = d->info.data + unit + off; if(dwarfnextsym(d, s) < 0) return -1; if(s->attrs.name==nil || strcmp(s->attrs.name, name)!=0){ werrstr("unexpected name %#q in lookup for %#q", s->attrs.name, name); return -1; } return 0; } } b.p = next; } werrstr("unknown name '%s'", name); return -1; }
/* * XXX This turns out to be much more expensive than the actual * running of the machine in dexec. It probably makes sense to * cache the last 10 or so fde's we've found, since stack traces * will keep asking for the same info over and over. */ static int findfde(Dwarf *d, ulong pc, State *s, DwarfBuf *fde) { static int nbad; char *aug; uchar *next; int i, vers; ulong len, id, base, size; DwarfBuf b; if(d->frame.data == nil){ werrstr("no frame debugging information"); return -1; } b.d = d; b.p = d->frame.data; b.ep = b.p + d->frame.len; b.addrsize = d->addrsize; if(b.addrsize == 0) b.addrsize = 4; /* where should i find this? */ for(; b.p < b.ep; b.p = next){ if((i = (b.p - d->frame.data) % b.addrsize)) b.p += b.addrsize - i; len = dwarfget4(&b); if(len > b.ep-b.p){ werrstr("bad length in cie/fde header"); return -1; } next = b.p+len; id = dwarfget4(&b); if(id == 0xFFFFFFFF){ /* CIE */ vers = dwarfget1(&b); if(vers != 1 && vers != 2 && vers != 3){ if(++nbad == 1) werrstr("unknown cie version %d (wanted 1-3)\n", vers); continue; } aug = dwarfgetstring(&b); if(aug && *aug){ if(++nbad == 1) werrstr("unknown augmentation: %s\n", aug); continue; } s->iquantum = dwarfget128(&b); s->dquantum = dwarfget128s(&b); s->rareg = dwarfget128(&b); if(s->rareg > s->nr){ werrstr("return address is register %d but only have %d registers", s->rareg, s->nr); return -1; } s->init.p = b.p; s->init.ep = next; }else{ /* FDE */ base = dwarfgetaddr(&b); size = dwarfgetaddr(&b); fde->p = b.p; fde->ep = next; s->loc = base; s->endloc = base+size; if(base <= pc && pc < base+size) return 0; } } werrstr("cannot find call frame information for pc 0x%lux", pc); return -1; }
int dwarfpctoline(Dwarf *d, DwarfSym *proc, ulong pc, char **file, char **function, ulong *line) { char *cdir; uchar *prog, *opcount, *end, *dirs; ulong off, unit, len, vers, x, start, lastline; int i, first, firstline, op, a, l, quantum, isstmt, linebase, linerange, opcodebase, nf; char *files, *s; DwarfBuf b; DwarfSym sym; State emit, cur, reset; char **f, **newf; f = nil; memset(proc, 0, sizeof(*proc)); int runit = dwarfaddrtounit(d, pc, &unit); if (runit < 0) return -1; int rtag = dwarflookuptag(d, unit, TagCompileUnit, &sym); if (rtag < 0) return -1; if(!sym.attrs.have.stmtlist){ werrstr("no line mapping information for 0x%x", pc); return -1; } off = sym.attrs.stmtlist; if(off >= d->line.len){ werrstr("bad stmtlist"); goto bad; } if(trace) werrstr("unit 0x%x stmtlist 0x%x", unit, sym.attrs.stmtlist); memset(&b, 0, sizeof b); b.d = d; b.p = d->line.data + off; b.ep = b.p + d->line.len; b.addrsize = sym.b.addrsize; /* should i get this from somewhere else? */ len = dwarfget4(&b); if(b.p==nil || b.p+len > b.ep || b.p+len < b.p){ werrstr("bad len"); goto bad; } b.ep = b.p+len; vers = dwarfget2(&b); if(vers != 2){ werrstr("bad dwarf version 0x%x", vers); return -1; } len = dwarfget4(&b); if(b.p==nil || b.p+len > b.ep || b.p+len < b.p){ werrstr("another bad len"); goto bad; } prog = b.p+len; quantum = dwarfget1(&b); isstmt = dwarfget1(&b); linebase = (schar)dwarfget1(&b); linerange = (schar)dwarfget1(&b); opcodebase = dwarfget1(&b); opcount = b.p-1; dwarfgetnref(&b, opcodebase-1); if(b.p == nil){ werrstr("bad opcode chart"); goto bad; } /* just skip the files and dirs for now; we'll come back */ dirs = b.p; while (b.p && *b.p) dwarfgetstring(&b); dwarfget1(&b); files = (char*)b.p; while(b.p!=nil && *b.p!=0){ dwarfgetstring(&b); dwarfget128(&b); dwarfget128(&b); dwarfget128(&b); } dwarfget1(&b); /* move on to the program */ if(b.p == nil || b.p > prog){ werrstr("bad header"); goto bad; } b.p = prog; reset.addr = 0; reset.file = 1; reset.line = 1; reset.column = 0; reset.flags = isstmt ? Isstmt : 0; reset.isa = 0; cur = reset; emit = reset; nf = 0; start = 0; if(trace) werrstr("program @ %lu ... %.*H opbase = %d", b.p - d->line.data, b.ep-b.p, b.p, opcodebase); first = 1; while(b.p != nil){ firstline = 0; op = dwarfget1(&b); if(trace) werrstr("\tline %lu, addr 0x%x, op %d %.10H", cur.line, cur.addr, op, b.p); if(op >= opcodebase){ a = (op - opcodebase) / linerange; l = (op - opcodebase) % linerange + linebase; cur.line += l; cur.addr += a * quantum; if(trace) werrstr(" +%d,%d", a, l); emit: if(first){ if(cur.addr > pc){ werrstr("found wrong line mapping 0x%x for pc 0x%x", cur.addr, pc); /* This is an overzealous check. gcc can produce discontiguous ranges and reorder statements, so it's possible for a future line to start ahead of pc and still find a matching one. */ /*goto out;*/ firstline = 1; } first = 0; start = cur.addr; } if(cur.addr > pc && !firstline) break; if(b.p == nil){ werrstr("buffer underflow in line mapping"); goto out; } emit = cur; if(emit.flags & EndSequence){ werrstr("found wrong line mapping 0x%x-0x%x for pc 0x%x", start, cur.addr, pc); goto out; } cur.flags &= ~(BasicDwarfBlock|PrologueEnd|EpilogueBegin); }else{ switch(op){ case 0: /* extended op code */ if(trace) werrstr(" ext"); len = dwarfget128(&b); end = b.p+len; if(b.p == nil || end > b.ep || end < b.p || len < 1) goto bad; switch(dwarfget1(&b)){ case 1: /* end sequence */ if(trace) werrstr(" end"); cur.flags |= EndSequence; goto emit; case 2: /* set address */ cur.addr = dwarfgetaddr(&b); if(trace) werrstr(" set pc 0x%x", cur.addr); break; case 3: /* define file */ newf = malloc(nf+1*sizeof(f[0])); if (newf) RtlMoveMemory(newf, f, nf*sizeof(f[0])); if(newf == nil) goto out; free(f); f = newf; f[nf++] = s = dwarfgetstring(&b); DPRINT1("str %s", s); dwarfget128(&b); dwarfget128(&b); dwarfget128(&b); if(trace) werrstr(" def file %s", s); break; } if(b.p == nil || b.p > end) goto bad; b.p = end; break; case 1: /* emit */ if(trace) werrstr(" emit"); goto emit; case 2: /* advance pc */ a = dwarfget128(&b); if(trace) werrstr(" advance pc + %lu", a*quantum); cur.addr += a * quantum; break; case 3: /* advance line */ l = dwarfget128s(&b); if(trace) werrstr(" advance line + %ld", l); cur.line += l; break; case 4: /* set file */ if(trace) werrstr(" set file"); cur.file = dwarfget128s(&b); break; case 5: /* set column */ if(trace) werrstr(" set column"); cur.column = dwarfget128(&b); break; case 6: /* negate stmt */ if(trace) werrstr(" negate stmt"); cur.flags ^= Isstmt; break; case 7: /* set basic block */ if(trace) werrstr(" set basic block"); cur.flags |= BasicDwarfBlock; break; case 8: /* const add pc */ a = (255 - opcodebase) / linerange * quantum; if(trace) werrstr(" const add pc + %d", a); cur.addr += a; break; case 9: /* fixed advance pc */ a = dwarfget2(&b); if(trace) werrstr(" fixed advance pc + %d", a); cur.addr += a; break; case 10: /* set prologue end */ if(trace) werrstr(" set prologue end"); cur.flags |= PrologueEnd; break; case 11: /* set epilogue begin */ if(trace) werrstr(" set epilogue begin"); cur.flags |= EpilogueBegin; break; case 12: /* set isa */ if(trace) werrstr(" set isa"); cur.isa = dwarfget128(&b); break; default: /* something new - skip it */ if(trace) werrstr(" unknown %d", opcount[op]); for(i=0; i<opcount[op]; i++) dwarfget128(&b); break; } } } if(b.p == nil) goto bad; /* finally! the data we seek is in "emit" */ if(emit.file == 0){ werrstr("invalid file index in mapping data"); goto out; } if(line) *line = emit.line; /* skip over first emit.file-2 guys */ b.p = (uchar*)files; for(i=emit.file-1; i > 0 && b.p!=nil && *b.p!=0; i--){ dwarfgetstring(&b); dwarfget128(&b); dwarfget128(&b); dwarfget128(&b); } if(b.p == nil){ werrstr("problem parsing file data second time (cannot happen)"); goto bad; } if(*b.p == 0){ if(i >= nf){ werrstr("bad file index in mapping data"); goto bad; } b.p = (uchar*)f[i]; } s = dwarfgetstring(&b); *file = s; i = dwarfget128(&b); /* directory */ x = dwarfget128(&b); x = dwarfget128(&b); /* fetch dir name */ cdir = sym.attrs.have.compdir ? sym.attrs.compdir : 0; char *dwarfdir; dwarfdir = nil; b.p = dirs; for (x = 1; b.p && *b.p; x++) { dwarfdir = dwarfgetstring(&b); if (x == i) break; } if (!cdir && dwarfdir) cdir = dwarfdir; char *filefull = malloc(strlen(cdir) + strlen(*file) + 2); strcpy(filefull, cdir); strcat(filefull, "/"); strcat(filefull, *file); *file = filefull; *function = nil; lastline = 0; runit = dwarfaddrtounit(d, pc, &unit); if (runit == 0) { DwarfSym compunit = { }; int renum = dwarfenumunit(d, unit, &compunit); if (renum < 0) return -1; renum = dwarfnextsymat(d, &compunit, proc); while (renum == 0) { if (proc->attrs.tag == TagSubprogram && proc->attrs.have.name) { if (proc->attrs.lowpc <= pc && proc->attrs.highpc > pc) { *function = malloc(strlen(proc->attrs.name)+1); strcpy(*function, proc->attrs.name); goto done; } } renum = dwarfnextsym(d, proc); } } // Next search by declaration runit = dwarfaddrtounit(d, pc, &unit); if (runit == 0) { DwarfSym compunit = { }; int renum = dwarfenumunit(d, unit, &compunit); if (renum < 0) return -1; renum = dwarfnextsymat(d, &compunit, proc); while (renum == 0) { if (proc->attrs.tag == TagSubprogram && proc->attrs.have.name && proc->attrs.declfile == emit.file) { if (proc->attrs.declline <= *line && proc->attrs.declline > lastline) { free(*function); *function = malloc(strlen(proc->attrs.name)+1); strcpy(*function, proc->attrs.name); goto done; } lastline = proc->attrs.declline; } renum = dwarfnextsym(d, proc); } } /* free at last, free at last */ done: free(f); return 0; bad: werrstr("corrupted line mapping for 0x%x", pc); out: free(f); return -1; }
int dwarfpctoline(Dwarf *d, ulong pc, char **cdir, char **dir, char **file, ulong *line, ulong *mtime, ulong *length) { uchar *prog, *opcount, *end; ulong off, unit, len, vers, x, start; int i, first, op, a, l, quantum, isstmt, linebase, linerange, opcodebase, nf; char *files, *dirs, *s; DwarfBuf b; DwarfSym sym; State emit, cur, reset; uchar **f, **newf; f = nil; if(dwarfaddrtounit(d, pc, &unit) < 0 || dwarflookuptag(d, unit, TagCompileUnit, &sym) < 0) return -1; if(!sym.attrs.have.stmtlist){ werrstr("no line mapping information for 0x%lux", pc); return -1; } off = sym.attrs.stmtlist; if(off >= d->line.len){ fprint(2, "bad stmtlist\n"); goto bad; } if(trace) fprint(2, "unit 0x%lux stmtlist 0x%lux\n", unit, sym.attrs.stmtlist); memset(&b, 0, sizeof b); b.d = d; b.p = d->line.data + off; b.ep = b.p + d->line.len; b.addrsize = sym.b.addrsize; /* should i get this from somewhere else? */ len = dwarfget4(&b); if(b.p==nil || b.p+len > b.ep || b.p+len < b.p){ fprint(2, "bad len\n"); goto bad; } b.ep = b.p+len; vers = dwarfget2(&b); if(vers != 2){ werrstr("bad dwarf version 0x%lux", vers); return -1; } len = dwarfget4(&b); if(b.p==nil || b.p+len > b.ep || b.p+len < b.p){ fprint(2, "another bad len\n"); goto bad; } prog = b.p+len; quantum = dwarfget1(&b); isstmt = dwarfget1(&b); linebase = (schar)dwarfget1(&b); linerange = (schar)dwarfget1(&b); opcodebase = dwarfget1(&b); opcount = b.p-1; dwarfgetnref(&b, opcodebase-1); if(b.p == nil){ fprint(2, "bad opcode chart\n"); goto bad; } /* just skip the files and dirs for now; we'll come back */ dirs = (char*)b.p; while(b.p!=nil && *b.p!=0) dwarfgetstring(&b); dwarfget1(&b); files = (char*)b.p; while(b.p!=nil && *b.p!=0){ dwarfgetstring(&b); dwarfget128(&b); dwarfget128(&b); dwarfget128(&b); } dwarfget1(&b); /* move on to the program */ if(b.p == nil || b.p > prog){ fprint(2, "bad header\n"); goto bad; } b.p = prog; reset.addr = 0; reset.file = 1; reset.line = 1; reset.column = 0; reset.flags = isstmt ? Isstmt : 0; reset.isa = 0; cur = reset; emit = reset; nf = 0; start = 0; if(trace) fprint(2, "program @ %lud ... %.*H opbase = %d\n", b.p - d->line.data, b.ep-b.p, b.p, opcodebase); first = 1; while(b.p != nil){ op = dwarfget1(&b); if(trace) fprint(2, "\tline %lud, addr 0x%lux, op %d %.10H", cur.line, cur.addr, op, b.p); if(op >= opcodebase){ a = (op - opcodebase) / linerange; l = (op - opcodebase) % linerange + linebase; cur.line += l; cur.addr += a * quantum; if(trace) fprint(2, " +%d,%d\n", a, l); emit: if(first){ if(cur.addr > pc){ werrstr("found wrong line mapping 0x%lux for pc 0x%lux", cur.addr, pc); goto out; } first = 0; start = cur.addr; } if(cur.addr > pc) break; if(b.p == nil){ werrstr("buffer underflow in line mapping"); goto out; } emit = cur; if(emit.flags & EndSequence){ werrstr("found wrong line mapping 0x%lux-0x%lux for pc 0x%lux", start, cur.addr, pc); goto out; } cur.flags &= ~(BasicDwarfBlock|PrologueEnd|EpilogueBegin); }else{ switch(op){ case 0: /* extended op code */ if(trace) fprint(2, " ext"); len = dwarfget128(&b); end = b.p+len; if(b.p == nil || end > b.ep || end < b.p || len < 1) goto bad; switch(dwarfget1(&b)){ case 1: /* end sequence */ if(trace) fprint(2, " end\n"); cur.flags |= EndSequence; goto emit; case 2: /* set address */ cur.addr = dwarfgetaddr(&b); if(trace) fprint(2, " set pc 0x%lux\n", cur.addr); break; case 3: /* define file */ newf = realloc(f, (nf+1)*sizeof(f[0])); if(newf == nil) goto out; f = newf; f[nf++] = b.p; s = dwarfgetstring(&b); dwarfget128(&b); dwarfget128(&b); dwarfget128(&b); if(trace) fprint(2, " def file %s\n", s); break; } if(b.p == nil || b.p > end) goto bad; b.p = end; break; case 1: /* emit */ if(trace) fprint(2, " emit\n"); goto emit; case 2: /* advance pc */ a = dwarfget128(&b); if(trace) fprint(2, " advance pc + %lud\n", a*quantum); cur.addr += a * quantum; break; case 3: /* advance line */ l = dwarfget128s(&b); if(trace) fprint(2, " advance line + %ld\n", l); cur.line += l; break; case 4: /* set file */ if(trace) fprint(2, " set file\n"); cur.file = dwarfget128s(&b); break; case 5: /* set column */ if(trace) fprint(2, " set column\n"); cur.column = dwarfget128(&b); break; case 6: /* negate stmt */ if(trace) fprint(2, " negate stmt\n"); cur.flags ^= Isstmt; break; case 7: /* set basic block */ if(trace) fprint(2, " set basic block\n"); cur.flags |= BasicDwarfBlock; break; case 8: /* const add pc */ a = (255 - opcodebase) / linerange * quantum; if(trace) fprint(2, " const add pc + %d\n", a); cur.addr += a; break; case 9: /* fixed advance pc */ a = dwarfget2(&b); if(trace) fprint(2, " fixed advance pc + %d\n", a); cur.addr += a; break; case 10: /* set prologue end */ if(trace) fprint(2, " set prologue end\n"); cur.flags |= PrologueEnd; break; case 11: /* set epilogue begin */ if(trace) fprint(2, " set epilogue begin\n"); cur.flags |= EpilogueBegin; break; case 12: /* set isa */ if(trace) fprint(2, " set isa\n"); cur.isa = dwarfget128(&b); break; default: /* something new - skip it */ if(trace) fprint(2, " unknown %d\n", opcount[op]); for(i=0; i<opcount[op]; i++) dwarfget128(&b); break; } } } if(b.p == nil) goto bad; /* finally! the data we seek is in "emit" */ if(emit.file == 0){ werrstr("invalid file index in mapping data"); goto out; } if(line) *line = emit.line; /* skip over first emit.file-2 guys */ b.p = (uchar*)files; for(i=emit.file-1; i > 0 && b.p!=nil && *b.p!=0; i--){ dwarfgetstring(&b); dwarfget128(&b); dwarfget128(&b); dwarfget128(&b); } if(b.p == nil){ werrstr("problem parsing file data second time (cannot happen)"); goto bad; } if(*b.p == 0){ if(i >= nf){ werrstr("bad file index in mapping data"); goto bad; } b.p = f[i]; } s = dwarfgetstring(&b); if(file) *file = s; i = dwarfget128(&b); /* directory */ x = dwarfget128(&b); if(mtime) *mtime = x; x = dwarfget128(&b); if(length) *length = x; /* fetch dir name */ if(cdir) *cdir = sym.attrs.compdir; if(dir){ if(i == 0) *dir = nil; else{ b.p = (uchar*)dirs; for(i--; i>0 && b.p!=nil && *b.p!=0; i--) dwarfgetstring(&b); if(b.p==nil || *b.p==0){ werrstr("bad directory reference in line mapping"); goto out; /* can only happen with bad dir index */ } *dir = dwarfgetstring(&b); } } /* free at last, free at last */ free(f); return 0; bad: werrstr("corrupted line mapping for 0x%lux", pc); out: free(f); return -1; }