Merge pull request #155 from bassosimone/feature/net-buffer

Improve net/buffer

doc/net/buffer.md

@@ -0,0 +1,99 @@
+# NAME
+Buffer - Buffer containing data.
+
+# LIBRARY
+MeasurementKit (libmeasurement-kit, -lmeasurement-kit).
+
+# SYNOPSIS
+
+```C++
+#include <measurement_kit/net.hpp>
+
+using namespace measurement_kit::common;
+using namespace measurement_kit::net;
+
+// Constructor
+
+Buffer buf;
+
+evbuffer *evbuf = /* something */ ;
+Buffer buf(evbuf);  // Move content from (evbuffer *) evbuf
+
+// Move data from/to other buffers (this does not entail copies)
+
+buf << bufferevent_get_input(bev);  // From bev to buf
+buf >> bufferevent_get_output(bev);  // The other way round
+
+Buffer another;
+buf << another;  // Move data from another to buf
+buf >> another;  // The other way round
+
+// Basic building blocks for high level functions
+
+size_t n = buf.length();
+
+// Walk over data and decide when to stop by returning false
+buf.foreach([](const char *p, size_t n) -> bool {
+    /* Do something with `p` and `n` */
+    return true;
+});
+
+// Discard, read and peek the buffer
+
+buf.discard(128);
+buf.discard();
+
+std::string s = buf.read(128);
+std::string s = buf.read();
+std::string s = buf.peek(128);
+std::string s = buf.peek();
+
+std::string s = buf.readn(1024);
+if (s == "") {
+    /* less than 1024 bytes buffered */
+    return;
+}
+
+Error error;
+std::string s;
+std::tie<error, s> res = buf.readline(1024);
+if (error != 0) {
+    /* readline failed, check error */
+    return;
+}
+
+// Write stuff
+
+std::string s;
+buf.write(s);
+buff << s;
+
+const char *s = "HTTP/1.1 200 Ok\r\n";
+buf.write(s);
+buf << s << "\r\n";
+
+buf.write("ciao", 4);
+
+buf.write_uint8('c');
+buf.write_uint16(1284);
+buf.write_uint32(7);
+
+buf.write_rand(2048);
+
+// Write directly into a 1024 chunk buffer of the output buffer chain
+buf.write(1024, [](char *buf, size_t cnt) -> size_t {
+    /* Write into `buf` up to `cnt` chars */
+    return cnt;
+});
+```
+
+# DESCRIPTION
+
+The `Buffer` object encapsulates an `evbuffer`. It is used to efficiently
+store data. You can move data from a `Buffer` to another `Buffer` at virtually
+not cost (the same is true when moving data from/to an `evbuffer` since
+that is internally used to implement a `Buffer`).
+
+# HISTORY
+
+The `Buffer` class appeared in MeasurementKit 0.1.

include/measurement_kit/http/http.hpp

@@ -603,7 +603,7 @@ class Request : public NonCopyable, public NonMovable {
             //       to reduce unnecessary copies
             Buffer buf;
             serializer.serialize(buf);
-            *stream << buf.read<char>();
+            *stream << buf.read();
 
             stream->on_flush([this]() {
                 logger->debug("http: request sent... waiting for response");