func NewUsercorn(exe string, config *models.Config) (models.Usercorn, error) {
config = config.Init()
f, err := os.Open(exe)
if err != nil {
return nil, err
}
defer f.Close()
l, err := loader.Load(f)
if err == loader.UnknownMagic {
f.Seek(0, 0)
scanner := bufio.NewScanner(f)
if scanner.Scan() {
line := scanner.Text()
if strings.HasPrefix(line, "#!") && len(line) > 2 {
args := strings.Split(line[2:], " ")
prefix := append(args[1:], exe)
config.PrefixArgs = append(prefix, config.PrefixArgs...)
shell := config.PrefixPath(args[0], false)
return NewUsercorn(shell, config)
}
}
}
if err != nil {
return nil, err
}
u, err := NewUsercornRaw(l, config)
if err != nil {
return nil, err
}
exe, _ = filepath.Abs(exe)
u.exe = exe
u.loader = l
// map binary (and interp) into memory
u.interpBase, u.entry, u.base, u.binEntry, err = u.mapBinary(f, false, l.Arch())
if err != nil {
return nil, err
}
// find data segment for brk
u.brk = 0
segments, err := l.Segments()
if err != nil {
return nil, err
}
for _, seg := range segments {
if seg.Prot&uc.PROT_WRITE != 0 {
addr := u.base + seg.Addr + seg.Size
if addr > u.brk {
u.brk = addr
}
}
}
// TODO: have a "host page size", maybe arch.Align()
// TODO: allow setting brk addr for raw Usercorn?
mask := uint64(4096 - 1)
u.Brk((u.brk + mask) & ^mask)
// make sure PC is set to entry point for debuggers
u.RegWrite(u.Arch().PC, u.Entry())
return u, nil
}
