Use C++11 features to manipulate containers

[libs/datafile.git] / source / binarywriter.cpp

diff --git a/source/binarywriter.cpp b/source/binarywriter.cpp
index c1e53fb5f23e7ca3622697c4e5e829383aeafd2f..be548446f2f1fca9fb564661d17bec4d686d6d97 100644 (file)
--- a/source/binarywriter.cpp
+++ b/source/binarywriter.cpp
@@ -1,5 +1,8 @@
+#include <limits>
 #include <msp/core/maputils.h>
 #include "binarywriter.h"
+#include "binfloat.h"
+#include "output.h"
 #include "statement.h"
 
 using namespace std;
@@ -7,13 +10,26 @@ using namespace std;
 namespace Msp {
 namespace DataFile {
 
-BinaryWriter::BinaryWriter(IO::Base &o):
+BinaryWriter::BinaryWriter(Output &o):
        WriterMode(o),
-       next_kwd_id(3),
-       next_str_id(1)
+       next_kwd_id(1),
+       next_str_id(1),
+       float_precision(32)
 {
-       dict[DictEntry("__kwd", "iss")] = 1;
-       dict[DictEntry("__str", "is")] = 2;
+       dict[StatementKey("__kwd", "iss")] = -1;
+       dict[StatementKey("__str", "is")] = -2;
+       dict[StatementKey("__flt", "i")] = -3;
+}
+
+void BinaryWriter::set_float_precision(unsigned fp)
+{
+       if(fp<16 || fp>64 || fp%8)
+               throw invalid_argument("BinaryWriter::set_float_precision");
+       float_precision = fp;
+       Statement fst;
+       fst.keyword = "__flt";
+       fst.args.push_back(float_precision);
+       write_(fst);
 }
 
 void BinaryWriter::write(const Statement &st)
@@ -24,49 +40,49 @@ void BinaryWriter::write(const Statement &st)
 
 void BinaryWriter::write_(const Statement &st)
 {
-       unsigned id = get_item(dict, DictEntry(st.keyword, st.get_signature()));
+       int id = get_item(dict, StatementKey(st.keyword, st.get_signature()));
 
        write_int(id);
-       for(Statement::Arguments::const_iterator j = st.args.begin(); j!=st.args.end(); ++j)
-               switch(j->get_signature())
+       for(const Value &a: st.args)
+               switch(a.get_signature())
                {
-               case IntType::signature:    write_int   (j->get<IntType::Store>()); break;
-               case StringType::signature: write_string(j->get<StringType::Store>()); break;
-               case BoolType::signature:   write_int   (j->get<BoolType::Store>()); break;
-               case FloatType::signature:  write_float (j->get<FloatType::Store>()); break;
-               case SymbolType::signature: write_symbol(j->get<SymbolType::Store>()); break;
+               case IntType::signature:    write_int   (a.get<IntType::Store>()); break;
+               case StringType::signature: write_string(a.get<StringType::Store>()); break;
+               case BoolType::signature:   write_int   (a.get<BoolType::Store>()); break;
+               case FloatType::signature:  write_float (a.get<FloatType::Store>()); break;
+               case SymbolType::signature: write_symbol(a.get<SymbolType::Store>()); break;
                }
 
        write_int(st.sub.size());
-       for(list<Statement>::const_iterator j = st.sub.begin(); j!=st.sub.end(); ++j)
-               write(*j);
+       for(const Statement &s: st.sub)
+               write(s);
 }
 
 void BinaryWriter::collect_keywords(const Statement &st)
 {
-       DictEntry de(st.keyword, st.get_signature());
+       StatementKey key(st.keyword, st.get_signature());
 
-       if(!dict.count(de))
+       if(!dict.count(key))
        {
                Statement kst;
                kst.keyword = "__kwd";
                kst.args.push_back(next_kwd_id);
-               kst.args.push_back(de.keyword);
-               kst.args.push_back(de.args);
+               kst.args.push_back(key.keyword);
+               kst.args.push_back(key.signature);
                write_(kst);
 
-               dict[de] = next_kwd_id++;
+               dict[key] = next_kwd_id++;
        }
 
-       for(ValueArray::const_iterator i = st.args.begin(); i!=st.args.end(); ++i)
+       for(const Value &a: st.args)
        {
-               char sig = i->get_signature();
+               char sig = a.get_signature();
                string str;
                if(sig==SymbolType::signature)
-                       str = i->get<Symbol>().name;
+                       str = a.get<Symbol>().name;
                else if(sig==StringType::signature)
                {
-                       str = i->get<string>();
+                       str = a.get<string>();
                        if(str.size()>32)
                                continue;
                }
@@ -85,8 +101,8 @@ void BinaryWriter::collect_keywords(const Statement &st)
                strings[str] = next_str_id++;
        }
 
-       for(list<Statement>::const_iterator i = st.sub.begin(); i!=st.sub.end(); ++i)
-               collect_keywords(*i);
+       for(const Statement &s: st.sub)
+               collect_keywords(s);
 }
 
 void BinaryWriter::write_int(IntType::Store n)
@@ -110,26 +126,50 @@ void BinaryWriter::write_string(const StringType::Store &s)
        else
        {
                write_int(s.size());
-               out.write(s.data(), s.size());
+               out.write(s);
        }
 }
 
 void BinaryWriter::write_float(FloatType::Store f)
 {
-       union
+       BinFloat bf;
+
+       if(numeric_limits<FloatType::Store>::is_iec559)
+               bf = BinFloat::explode_iec559(f);
+       else
        {
-               float v;
-               char d[sizeof(float)];
-       };
-
-       v = f;
-#if BYTE_ORDER == LITTLE_ENDIAN
-       for(unsigned i = sizeof(float); i--;)
-               out.put(d[i]);
-#else
-       for(unsigned i = 0; i<sizeof(float); ++i)
-               out.put(d[i]);
-#endif
+               /* The structure of the float is unknown, so we must use arithmetic to
+               reduce it to components. */
+               bf.sign = f<0;
+               bf.exponent = 0;
+               bf.mantissa = 0;
+
+               if(f<0)
+                       f = -f;
+               if(!(f+f>f))
+                       bf.infinity = true;
+               else if(f!=0)
+               {
+                       for(; f<1; f*=2)
+                               --bf.exponent;
+                       for(; f>=2; f/=2)
+                               ++bf.exponent;
+                       for(unsigned i=0; i<64; ++i)
+                       {
+                               bf.mantissa <<= 1;
+                               if(f>=1)
+                               {
+                                       bf.mantissa |= 1;
+                                       f -= 1;
+                               }
+                               f *= 2;
+                       }
+               }
+       }
+
+       UInt64 encoded = bf.compose(float_precision);
+       for(unsigned i=float_precision/8; i--; )
+               out.put((encoded>>(i*8))&0xFF);
 }
 
 void BinaryWriter::write_symbol(const SymbolType::Store &s)