Split out socket related code into its own file.

1 files changed, 155 insertions, 0 deletions

diff --git a/comms.c b/comms.c
new file mode 100644
index 0000000..46a2b7e
--- /dev/null
+++ b/comms.c
@@ -0,0 +1,155 @@
+/* Random Instruction Sequences for Userspace 
+ * Copyright 2010 Linaro Limited
+ *
+ * Routines for the socket communication between master and apprentice.
+ */
+
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <netinet/in.h>
+#include <netdb.h>
+
+#include "risu.h"
+
+int apprentice_connect(const char *hostname, uint16_t port)
+{
+   /* We are the client end of the TCP connection */
+   int sock;
+   struct sockaddr_in sa;
+   sock = socket(PF_INET, SOCK_STREAM, 0);
+   if (sock < 0)
+   {
+      perror("socket");
+      exit(1);
+   }
+   struct hostent *hostinfo;
+   sa.sin_family = AF_INET;
+   sa.sin_port = htons(port);
+   hostinfo = gethostbyname(hostname);
+   if (!hostinfo)
+   {
+      fprintf(stderr, "Unknown host %s\n", hostname);
+      exit(1);
+   }
+   sa.sin_addr = *(struct in_addr*)hostinfo->h_addr;
+   if (connect(sock, (struct sockaddr*)&sa, sizeof(sa)) < 0)
+   {
+      perror("connect");
+      exit(1);
+   }
+   return sock;
+}
+
+int master_connect(uint16_t port)
+{
+   int sock;
+   struct sockaddr_in sa;
+   sock = socket(PF_INET, SOCK_STREAM, 0);
+   if (sock < 0)
+   {
+      perror("socket");
+      exit(1);
+   }
+   int sora = 1;
+   if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &sora, sizeof(sora)) != 0)
+   {
+      perror("setsockopt(SO_REUSEADDR)");
+      exit(1);
+   }
+
+   sa.sin_family = AF_INET;
+   sa.sin_port = htons(port);
+   sa.sin_addr.s_addr = htonl(INADDR_ANY);
+   if (bind(sock, (struct sockaddr*)&sa, sizeof(sa)) < 0)
+   {
+      perror("bind");
+      exit(1);
+   }
+   if (listen(sock, 1) < 0)
+   {
+      perror("listen");
+      exit(1);
+   }
+   /* Just block until we get a connection */
+   fprintf(stderr, "master: waiting for connection on port %d...\n", port);
+   struct sockaddr_in csa;
+   size_t csasz;
+   int nsock = accept(sock, (struct sockaddr*)&csa, &csasz);
+   if (nsock < 0)
+   {
+      perror("accept");
+      exit(1);
+   }
+   /* We're done with the server socket now */
+   close(sock);
+   return nsock;
+}
+
+/* The communication protocol is very simple.
+ * The apprentice sends a packet like this:
+ *  4 bytes: faulting insn
+ *  n bytes: register dump
+ * The master replies with a single byte response:
+ *  0: ok, continue  [registers matched]
+ *  1: exit with status 0 [end of test]
+ *  2: exit with status 1 [mismatch, fail]
+ *
+ * We can handle the variable-length packet at setup
+ * (where the apprentice sends command line options,
+ * random seed etc) by first sending the length alone
+ * as a 4-byte packet, and then a packet of that length.
+ */
+
+int send_data_pkt(int sock, void *pkt, int pktlen)
+{
+   unsigned char resp;
+   char *p = pkt;
+   while (pktlen)
+   {
+      int i = write(sock, p, pktlen);
+      if (i <= 0)
+      {
+         perror("write failed");
+         exit(1);
+      }
+      pktlen -= i;
+      p += i;
+   }
+   if (read(sock, &resp, 1) != 1)
+   {
+      perror("read failed");
+      exit(1);
+   }
+   return resp;
+}
+
+void recv_data_pkt(int sock, void *pkt, int pktlen)
+{
+   /* We always read a fixed length packet */ 
+   char *p = pkt;
+   while (pktlen)
+   {
+      int i = read(sock, p, pktlen);
+      if (i <= 0)
+      {
+         perror("read failed");
+         exit(1);
+      }
+      pktlen -= i;
+      p += i;
+   }
+}
+
+void send_response_byte(int sock, int resp)
+{
+   unsigned char r = resp;
+   if (write(sock, &r, 1) != 1)
+   {
+      perror("write failed");
+      exit(1);
+   }   
+}