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#include "serialise.hh"
#include "util.hh"
namespace nix {
void FdSink::operator () (const unsigned char * data, unsigned int len)
{
writeFull(fd, data, len);
}
void FdSource::operator () (unsigned char * data, unsigned int len)
{
readFull(fd, data, len);
}
void writePadding(unsigned int len, Sink & sink)
{
if (len % 8) {
unsigned char zero[8];
memset(zero, 0, sizeof(zero));
sink(zero, 8 - (len % 8));
}
}
void writeInt(unsigned int n, Sink & sink)
{
unsigned char buf[8];
memset(buf, 0, sizeof(buf));
buf[0] = n & 0xff;
buf[1] = (n >> 8) & 0xff;
buf[2] = (n >> 16) & 0xff;
buf[3] = (n >> 24) & 0xff;
sink(buf, sizeof(buf));
}
void writeString(const string & s, Sink & sink)
{
unsigned int len = s.length();
writeInt(len, sink);
sink((const unsigned char *) s.c_str(), len);
writePadding(len, sink);
}
void writeStringSet(const StringSet & ss, Sink & sink)
{
writeInt(ss.size(), sink);
for (StringSet::iterator i = ss.begin(); i != ss.end(); ++i)
writeString(*i, sink);
}
void readPadding(unsigned int len, Source & source)
{
if (len % 8) {
unsigned char zero[8];
unsigned int n = 8 - (len % 8);
source(zero, n);
for (unsigned int i = 0; i < n; i++)
if (zero[i]) throw Error("non-zero padding");
}
}
unsigned int readInt(Source & source)
{
unsigned char buf[8];
source(buf, sizeof(buf));
if (buf[4] || buf[5] || buf[6] || buf[7])
throw Error("implementation cannot deal with > 32-bit integers");
return
buf[0] |
(buf[1] << 8) |
(buf[2] << 16) |
(buf[3] << 24);
}
string readString(Source & source)
{
unsigned int len = readInt(source);
char buf[len];
source((unsigned char *) buf, len);
readPadding(len, source);
return string(buf, len);
}
StringSet readStringSet(Source & source)
{
unsigned int count = readInt(source);
StringSet ss;
while (count--)
ss.insert(readString(source));
return ss;
}
}
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