From 68474b1bed5657b4d8fab417d06abd47de70767d Mon Sep 17 00:00:00 2001
From: rsiddharth <s@ricketyspace.net>
Date: Mon, 16 Sep 2019 20:36:56 -0400
Subject: nserver: Add necho.h.

---
 nserver/src/necho.c | 64 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 nserver/src/necho.h | 15 +++++++++++++
 2 files changed, 79 insertions(+)
 create mode 100644 nserver/src/necho.c
 create mode 100644 nserver/src/necho.h

diff --git a/nserver/src/necho.c b/nserver/src/necho.c
new file mode 100644
index 0000000..b08889a
--- /dev/null
+++ b/nserver/src/necho.c
@@ -0,0 +1,64 @@
+#include <necho.h>
+
+int slurpsock(RingBuffer *buf, int sock)
+{
+    ssize_t bytes;
+
+    if (RingBuffer_available_data(buf) ==  0)  {
+        buf->start = buf->end = 0;
+    }
+
+    bytes = recv(sock, RingBuffer_starts_at(buf),
+              RingBuffer_available_space(buf), 0);
+    check(bytes >= 0, "Failed to read from socket: %d", sock);
+
+    RingBuffer_commit_write(buf, bytes);
+
+    return bytes;
+
+ error:
+    return -1;
+}
+
+int barfsock(int sock, RingBuffer *buf, int len)
+{
+    int bytes = 0;
+
+    bstring data = RingBuffer_get_all(buf);
+    check(data != NULL, "barfsock: Failed to get from the buffer.");
+
+    bytes = send(sock, bdata(data), len, 0);
+    check(bytes >= 0, "barfsock: send failed");
+
+    return bytes;
+ error:
+    return -1;
+}
+
+void echoserve(int sock)
+{
+    int rc = 0;
+    RingBuffer *buf = RingBuffer_create(1024 * 10);
+    ssize_t bytes;
+
+    do {
+        bytes = slurpsock(buf, sock);
+        check(bytes >= 0, "echoserve: slurpsock failed");
+
+        if (bytes < 1) {
+            break;
+        }
+
+        rc = barfsock(sock, buf, bytes);
+        check(rc != -1, "echoserve: echo failed");
+    } while(1);
+
+    rc = close(sock);
+    check(rc == 0, "echoserve: close failed");
+
+    exit(0);
+ error:
+    rc = close(sock);
+    check(rc == 0, "echoserve: close failed");
+    exit(1);
+}
diff --git a/nserver/src/necho.h b/nserver/src/necho.h
new file mode 100644
index 0000000..658c277
--- /dev/null
+++ b/nserver/src/necho.h
@@ -0,0 +1,15 @@
+#ifndef _necho_h
+#define _necho_h
+
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/socket.h>
+
+#include <bstrlib.h>
+#include <dbg.h>
+#include <ringbuffer.h>
+
+int echo(int sock, char *buf, int len);
+void echoserve(int sock);
+
+#endif
-- 
cgit v1.2.3