Files
gf-core/src/runtime/c/pgf/reader.cxx

431 lines
11 KiB
C++

#include "data.h"
#include "reader.h"
#include <math.h>
#include <string.h>
PgfReader::PgfReader(std::istream *in)
{
this->in = in;
}
uint8_t PgfReader::read_uint8()
{
uint8_t b;
in->read((char*) &b, sizeof(b));
if (in->eof())
throw pgf_error("reached end of file while reading a grammar");
if (in->fail())
throw std::system_error(errno, std::generic_category());
return b;
}
uint16_t PgfReader::read_u16be()
{
uint8_t buf[2];
in->read((char*) &buf, sizeof(buf));
if (in->eof())
throw pgf_error("reached end of file while reading a grammar");
if (in->fail())
throw std::system_error(errno, std::generic_category());
return (((uint16_t) buf[0]) << 8 | buf[1]);
}
uint64_t PgfReader::read_u64be()
{
uint8_t buf[8];
in->read((char*) &buf, sizeof(buf));
if (in->eof())
throw pgf_error("reached end of file while reading a grammar");
if (in->fail())
throw std::system_error(errno, std::generic_category());
return (((uint64_t) buf[0]) << 56 |
((uint64_t) buf[1]) << 48 |
((uint64_t) buf[2]) << 40 |
((uint64_t) buf[3]) << 32 |
((uint64_t) buf[4]) << 24 |
((uint64_t) buf[5]) << 16 |
((uint64_t) buf[6]) << 8 |
((uint64_t) buf[7]));
}
double PgfReader::read_double()
{
uint64_t u = read_u64be();
bool sign = u >> 63;
unsigned rawexp = u >> 52 & 0x7ff;
uint64_t mantissa = u & 0xfffffffffffff;
double ret;
if (rawexp == 0x7ff) {
ret = (mantissa == 0) ? INFINITY : NAN;
} else {
uint64_t m = rawexp ? 1ULL << 52 | mantissa : mantissa << 1;
ret = ldexp((double) m, rawexp - 1075);
}
return sign ? copysign(ret, -1.0) : ret;
}
uint64_t PgfReader::read_uint()
{
uint64_t u = 0;
int shift = 0;
uint8_t b = 0;
do {
b = read_uint8();
u |= (b & ~0x80) << shift;
shift += 7;
} while (b & 0x80);
return u;
}
object PgfReader::read_name_internal(size_t struct_size)
{
size_t size = read_len();
object offs = current_db->malloc_internal(struct_size+sizeof(PgfText)+size+1);
PgfText* ptext = (PgfText*) (current_base+offs+struct_size);
ptext->size = size;
// If reading the extra bytes causes EOF, it is an encoding
// error, not a legitimate end of character stream.
in->read(ptext->text, size);
if (in->eof())
throw pgf_error("utf8 decoding error");
if (in->fail())
throw std::system_error(errno, std::generic_category());
ptext->text[size+1] = 0;
return offs;
}
object PgfReader::read_text_internal(size_t struct_size)
{
size_t len = read_len();
char* buf = (char*) alloca(len*6+1);
char* p = buf;
for (size_t i = 0; i < len; i++) {
uint8_t c = read_uint8();
*(p++) = (char) c;
if (c < 0x80) {
continue;
}
if (c < 0xc2) {
throw pgf_error("utf8 decoding error");
}
int len = (c < 0xe0 ? 1 :
c < 0xf0 ? 2 :
c < 0xf8 ? 3 :
c < 0xfc ? 4 :
5
);
// If reading the extra bytes causes EOF, it is an encoding
// error, not a legitimate end of character stream.
in->read(p, len);
if (in->eof())
throw pgf_error("utf8 decoding error");
if (in->fail())
throw std::system_error(errno, std::generic_category());
p += len;
}
size_t size = p-buf;
*p++ = 0;
object offs = current_db->malloc_internal(struct_size+sizeof(PgfText)+size+1);
PgfText* ptext = (PgfText*) (current_base+offs+struct_size);
ptext->size = size;
memcpy(ptext->text, buf, size+1);
return offs;
}
template<class V>
Namespace<V> PgfReader::read_namespace(ref<V> (PgfReader::*read_value)())
{
size_t len = read_len();
Namespace<V> nmsp = 0;
for (size_t i = 0; i < len; i++) {
ref<V> value = (this->*read_value)();
nmsp = namespace_insert(nmsp, value);
}
return nmsp;
}
template <class C, class V>
ref<C> PgfReader::read_vector(PgfVector<V> C::* field, void (PgfReader::*read_value)(ref<V> val))
{
size_t len = read_len();
ref<C> loc = vector_new<C,V>(field,len);
for (size_t i = 0; i < len; i++) {
(this->*read_value)(vector_elem(ref<PgfVector<V>>::from_ptr(&(loc->*field)),i));
}
return loc;
}
template <class V>
ref<PgfVector<V>> PgfReader::read_vector(void (PgfReader::*read_value)(ref<V> val))
{
size_t len = read_len();
ref<PgfVector<V>> vec = vector_new<V>(len);
for (size_t i = 0; i < len; i++) {
(this->*read_value)(vector_elem(vec,i));
}
return vec;
}
PgfLiteral PgfReader::read_literal()
{
PgfLiteral lit = 0;
uint8_t tag = read_tag();
switch (tag) {
case PgfLiteralStr::tag: {
ref<PgfLiteralStr> lit_str =
read_text<PgfLiteralStr>(&PgfLiteralStr::val);
lit = ref<PgfLiteralStr>::tagged(lit_str);
break;
}
case PgfLiteralInt::tag: {
ref<PgfLiteralInt> lit_int =
DB::malloc<PgfLiteralInt>(tag);
lit_int->val = read_int();
lit = ref<PgfLiteralInt>::tagged(lit_int);
break;
}
case PgfLiteralFlt::tag: {
ref<PgfLiteralFlt> lit_flt =
current_db->malloc<PgfLiteralFlt>();
lit_flt->val = read_double();
lit = ref<PgfLiteralFlt>::tagged(lit_flt);
break;
}
default:
throw pgf_error("Unknown literal tag");
}
return lit;
}
ref<PgfFlag> PgfReader::read_flag()
{
ref<PgfFlag> flag = read_name(&PgfFlag::name);
flag->value = read_literal();
return flag;
}
PgfExpr PgfReader::read_expr()
{
PgfExpr expr = 0;
uint8_t tag = read_tag();
switch (tag) {
case PgfExprAbs::tag:{
PgfBindType bind_type = (PgfBindType) read_tag();
ref<PgfExprAbs> eabs = read_name(&PgfExprAbs::name);
eabs->bind_type = bind_type;
eabs->body = read_expr();
expr = ref<PgfExprAbs>::tagged(eabs);
break;
}
case PgfExprApp::tag: {
ref<PgfExprApp> eapp = DB::malloc<PgfExprApp>();
eapp->fun = read_expr();
eapp->arg = read_expr();
expr = ref<PgfExprApp>::tagged(eapp);
break;
}
case PgfExprLit::tag: {
ref<PgfExprLit> elit = DB::malloc<PgfExprLit>();
elit->lit = read_literal();
expr = ref<PgfExprLit>::tagged(elit);
break;
}
case PgfExprMeta::tag: {
ref<PgfExprMeta> emeta = DB::malloc<PgfExprMeta>();
emeta->id = read_int();
expr = ref<PgfExprMeta>::tagged(emeta);
break;
}
case PgfExprFun::tag: {
ref<PgfExprFun> efun = read_name(&PgfExprFun::name);
expr = ref<PgfExprFun>::tagged(efun);
break;
}
case PgfExprVar::tag: {
ref<PgfExprVar> evar = DB::malloc<PgfExprVar>();
evar->var = read_int();
expr = ref<PgfExprVar>::tagged(evar);
break;
}
case PgfExprTyped::tag: {
ref<PgfExprTyped> etyped = DB::malloc<PgfExprTyped>();
etyped->expr = read_expr();
etyped->type = read_type();
expr = ref<PgfExprTyped>::tagged(etyped);
break;
}
case PgfExprImplArg::tag: {
ref<PgfExprImplArg> eimpl = current_db->malloc<PgfExprImplArg>();
eimpl->expr = read_expr();
expr = ref<PgfExprImplArg>::tagged(eimpl);
break;
}
default:
throw pgf_error("Unknown expression tag");
}
return expr;
}
void PgfReader::read_hypo(ref<PgfHypo> hypo)
{
hypo->bind_type = (PgfBindType) read_tag();
hypo->cid = read_name();
hypo->type = read_type();
}
ref<PgfDTyp> PgfReader::read_type()
{
ref<PgfVector<PgfHypo>> hypos =
read_vector<PgfHypo>(&PgfReader::read_hypo);
ref<PgfDTyp> tp = read_name<PgfDTyp>(&PgfDTyp::name);
tp->hypos = hypos;
tp->exprs =
read_vector<PgfExpr>(&PgfReader::read_expr);
return tp;
}
PgfPatt PgfReader::read_patt()
{
PgfPatt patt = 0;
uint8_t tag = read_tag();
switch (tag) {
case PgfPattApp::tag: {
ref<PgfText> ctor = read_name();
ref<PgfPattApp> papp =
read_vector<PgfPattApp,PgfPatt>(&PgfPattApp::args,&PgfReader::read_patt2);
papp->ctor = ctor;
patt = ref<PgfPattApp>::tagged(papp);
break;
}
case PgfPattVar::tag: {
ref<PgfPattVar> pvar = read_name<PgfPattVar>(&PgfPattVar::name);
patt = ref<PgfPattVar>::tagged(pvar);
break;
}
case PgfPattAs::tag: {
ref<PgfPattAs> pas = read_name<PgfPattAs>(&PgfPattAs::name);
pas->patt = read_patt();
patt = ref<PgfPattAs>::tagged(pas);
break;
}
case PgfPattWild::tag: {
ref<PgfPattWild> pwild = DB::malloc<PgfPattWild>();
patt = ref<PgfPattWild>::tagged(pwild);
break;
}
case PgfPattLit::tag: {
ref<PgfPattLit> plit = DB::malloc<PgfPattLit>();
plit->lit = read_literal();
patt = ref<PgfPattLit>::tagged(plit);
break;
}
case PgfPattImplArg::tag: {
ref<PgfPattImplArg> pimpl = DB::malloc<PgfPattImplArg>();
pimpl->patt = read_patt();
patt = ref<PgfPattImplArg>::tagged(pimpl);
break;
}
case PgfPattTilde::tag: {
ref<PgfPattTilde> ptilde = DB::malloc<PgfPattTilde>();
ptilde->expr = read_expr();
patt = ref<PgfPattTilde>::tagged(ptilde);
break;
}
default:
throw pgf_error("Unknown pattern tag");
}
return patt;
}
void PgfReader::read_defn(ref<ref<PgfEquation>> defn)
{
ref<PgfEquation> eq = read_vector(&PgfEquation::patts,&PgfReader::read_patt2);
eq->body = read_expr();
*defn = eq;
}
ref<PgfAbsFun> PgfReader::read_absfun()
{
ref<PgfAbsFun> absfun =
read_name<PgfAbsFun>(&PgfAbsFun::name);
ref<PgfExprFun> efun =
ref<PgfExprFun>::from_ptr((PgfExprFun*) &absfun->name);
absfun->ep.expr = ref<PgfExprFun>::tagged(efun);
absfun->type = read_type();
absfun->arity = read_int();
uint8_t tag = read_tag();
switch (tag) {
case 0:
absfun->defns = 0;
break;
case 1:
absfun->defns =
read_vector<ref<PgfEquation>>(&PgfReader::read_defn);
break;
default:
throw pgf_error("Unknown tag, 0 or 1 expected");
}
absfun->ep.prob = - log(read_double());
return absfun;
}
ref<PgfAbsCat> PgfReader::read_abscat()
{
ref<PgfAbsCat> abscat = read_name<PgfAbsCat>(&PgfAbsCat::name);
abscat->context = read_vector<PgfHypo>(&PgfReader::read_hypo);
// for now we just read the set of functions per category and ignore them
size_t n_funs = read_len();
for (size_t i = 0; i < n_funs; i++) {
read_double();
read_name();
}
abscat->prob = - log(read_double());
return abscat;
}
void PgfReader::read_abstract(ref<PgfAbstr> abstract)
{
abstract->name = read_name();
abstract->aflags = read_namespace<PgfFlag>(&PgfReader::read_flag);
abstract->funs = read_namespace<PgfAbsFun>(&PgfReader::read_absfun);
abstract->cats = read_namespace<PgfAbsCat>(&PgfReader::read_abscat);
}
ref<PgfPGFRoot> PgfReader::read_pgf()
{
ref<PgfPGFRoot> pgf = DB::malloc<PgfPGFRoot>();
pgf->major_version = read_u16be();
pgf->minor_version = read_u16be();
pgf->gflags = read_namespace<PgfFlag>(&PgfReader::read_flag);
read_abstract(ref<PgfAbstr>::from_ptr(&pgf->abstract));
return pgf;
}