func (r *randGen) generateArg(s *state, typ sys.Type) (arg *Arg, calls []*Call) {
if typ.Dir() == sys.DirOut {
// No need to generate something interesting for output scalar arguments.
// But we still need to generate the argument itself so that it can be referenced
// in subsequent calls. For the same reason we do generate pointer/array/struct
// output arguments (their elements can be referenced in subsequent calls).
switch typ.(type) {
case *sys.IntType, *sys.FlagsType, *sys.ConstType,
*sys.ResourceType, *sys.VmaType, *sys.ProcType:
return constArg(typ, typ.Default()), nil
}
}
if typ.Optional() && r.oneOf(5) {
if _, ok := typ.(*sys.BufferType); ok {
panic("impossible") // parent PtrType must be Optional instead
}
return constArg(typ, typ.Default()), nil
}
switch a := typ.(type) {
case *sys.ResourceType:
r.choose(
1, func() {
special := a.SpecialValues()
arg = constArg(a, special[r.Intn(len(special))])
},
90, func() {
// Get an existing resource.
var allres []*Arg
for name1, res1 := range s.resources {
if sys.IsCompatibleResource(a.Desc.Name, name1) ||
r.oneOf(20) && sys.IsCompatibleResource(a.Desc.Kind[0], name1) {
allres = append(allres, res1...)
}
}
if len(allres) != 0 {
arg = resultArg(a, allres[r.Intn(len(allres))])
} else {
arg, calls = r.createResource(s, a)
}
},
5, func() {
// Create a new resource.
arg, calls = r.createResource(s, a)
},
)
return arg, calls
case *sys.BufferType:
switch a.Kind {
case sys.BufferBlobRand, sys.BufferBlobRange:
sz := r.randBufLen()
if a.Kind == sys.BufferBlobRange {
sz = r.randRange(int(a.RangeBegin), int(a.RangeEnd))
}
data := make([]byte, sz)
if a.Dir() != sys.DirOut {
for i := range data {
data[i] = byte(r.Intn(256))
}
}
return dataArg(a, data), nil
case sys.BufferString:
data := r.randString(s, a.Values, a.Dir())
return dataArg(a, data), nil
case sys.BufferFilename:
filename := r.filename(s)
return dataArg(a, []byte(filename)), nil
default:
panic("unknown buffer kind")
}
case *sys.VmaType:
npages := r.randPageCount()
arg := r.randPageAddr(s, a, npages, nil, true)
return arg, nil
case *sys.FlagsType:
return constArg(a, r.flags(a.Vals)), nil
case *sys.ConstType:
return constArg(a, a.Val), nil
case *sys.IntType:
v := r.randInt()
switch a.Kind {
case sys.IntSignalno:
v %= 130
case sys.IntFileoff:
r.choose(
90, func() { v = 0 },
10, func() { v = r.rand(100) },
1, func() { v = r.randInt() },
)
case sys.IntRange:
v = r.randRangeInt(a.RangeBegin, a.RangeEnd)
}
return constArg(a, v), nil
case *sys.ProcType:
return constArg(a, r.rand(int(a.ValuesPerProc))), nil
case *sys.ArrayType:
count := uintptr(0)
switch a.Kind {
case sys.ArrayRandLen:
count = r.rand(6)
case sys.ArrayRangeLen:
count = r.randRange(int(a.RangeBegin), int(a.RangeEnd))
}
var inner []*Arg
var calls []*Call
for i := uintptr(0); i < count; i++ {
arg1, calls1 := r.generateArg(s, a.Type)
inner = append(inner, arg1)
calls = append(calls, calls1...)
}
return groupArg(a, inner), calls
case *sys.StructType:
if ctor := isSpecialStruct(a); ctor != nil && a.Dir() != sys.DirOut {
arg, calls = ctor(r, s)
return
}
args, calls := r.generateArgs(s, a.Fields)
group := groupArg(a, args)
return group, calls
case *sys.UnionType:
optType := a.Options[r.Intn(len(a.Options))]
opt, calls := r.generateArg(s, optType)
return unionArg(a, opt, optType), calls
case *sys.PtrType:
inner, calls := r.generateArg(s, a.Type)
if a.Dir() == sys.DirOut && inner == nil {
// No data, but we should have got size.
arg, calls1 := r.addr(s, a, inner.Size(), nil)
calls = append(calls, calls1...)
return arg, calls
}
if a.Type.Name() == "iocb" && len(s.resources["iocbptr"]) != 0 {
// It is weird, but these are actually identified by kernel by address.
// So try to reuse a previously used address.
addrs := s.resources["iocbptr"]
addr := addrs[r.Intn(len(addrs))]
arg = pointerArg(a, addr.AddrPage, addr.AddrOffset, addr.AddrPagesNum, inner)
return arg, calls
}
arg, calls1 := r.addr(s, a, inner.Size(), inner)
calls = append(calls, calls1...)
return arg, calls
case *sys.LenType:
// Return placeholder value of 0 while generating len args.
return constArg(a, 0), nil
default:
panic("unknown argument type")
}
}
