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-rw-r--r--src/libutil/serialise.cc87
1 files changed, 87 insertions, 0 deletions
diff --git a/src/libutil/serialise.cc b/src/libutil/serialise.cc
new file mode 100644
index 000000000..aa11c590a
--- /dev/null
+++ b/src/libutil/serialise.cc
@@ -0,0 +1,87 @@
+#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 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);
+}
+
+
+}