#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); unsigned char * buf = new unsigned char[len]; AutoDeleteArray<unsigned char> d(buf); source(buf, len); readPadding(len, source); return string((char *) buf, len); } StringSet readStringSet(Source & source) { unsigned int count = readInt(source); StringSet ss; while (count--) ss.insert(readString(source)); return ss; } }