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#include <midillo/util.h>
#include <midillo/exception.h>
namespace midillo {
unsigned long read32(istream& s) {
unsigned long rv = 0;
for(int t=0;t<4;++t) {
rv<<=8;
rv|=0xFF&s.get();
if(!s.good())
throw exception_input_error(CODEPOINT,"Input error");
}
return rv;
}
unsigned int read16(istream& s) {
unsigned int rv = 0;
for(int t=0;t<2;++t) {
rv<<=8;
rv|=0xFF&s.get();
if(!s.good())
throw exception_input_error(CODEPOINT,"Input error");
}
return rv;
}
unsigned long readVL(istream& s) {
unsigned long rv=s.get();
if(!s.good())
throw exception_input_error(CODEPOINT,"Error reading VLQ");
int b;
if(rv&0x80) {
rv&=0x7F;
do {
rv = (rv<<7)|( (b=s.get())&0x7F );
if(!s.good())
throw exception_input_error(CODEPOINT,"Error reading VLQ");
}while(b&0x80);
}
return rv;
}
void write32(ostream& s,unsigned long d) {
for(int t=3;t>=0;--t) {
s.put(((const char*)&d)[t]);
if(!s.good())
throw exception_output_error(CODEPOINT,"Output error");
}
}
void write16(ostream& s,unsigned int d) {
for(int t=1;t>=0;--t) {
s.put(((const char*)&d)[t]);
if(!s.good())
throw exception_output_error(CODEPOINT,"Output error");
}
}
void writeVL(ostream& s,unsigned long d) {
// TODO: I don't think this is perfectly written code
unsigned long tmp = d&0x7F;
while(d>>=7) {
tmp<<=8;
tmp |=((d&0x7F)|0x80);
}
for(;;) {
s.put(tmp&0xFF);
if(!s.good())
throw exception_output_error(CODEPOINT,"Error writing VLQ");
if(tmp&0x80)
tmp>>=8;
else
break;
}
}
unsigned long calcVLsize(unsigned long d) {
unsigned long rv = 0;
// TODO: imperfect code revisited
unsigned long tmp = d&0x7F;
while(d>>=7) {
tmp<<=8;
tmp |=((d&0x7F)|0x80);
}
for(;;) {
++rv;
if(tmp&0x80)
tmp>>=8;
else
break;
}
return rv;
}
}
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