[client] added initial ivshmem client implementation

client/Makefile

@@ -10,4 +10,4 @@ LDFLAGS+=`pkg-config --libs libssl openssl`
 CFLAGS+=`pkg-config --cflags spice-protocol`
 
 all:
-	gcc ${CFLAGS} -o main main.c spice/spice.c ${LDFLAGS}
+	gcc ${CFLAGS} -o main main.c spice/spice.c ivshmem/ivshmem.c ${LDFLAGS}

client/debug.h

@@ -1,3 +1,5 @@
+#include <stdio.h>
+
 #ifdef DEBUG
   #define DEBUG_PRINT(type, fmt, args...) do {fprintf(stderr, type " %-30s : %-5u | " fmt "\n", __FUNCTION__, __LINE__, ##args);} while (0)
 #else
@@ -9,7 +11,7 @@
 #define DEBUG_ERROR(fmt, args...) DEBUG_PRINT("[E]", fmt, ##args)
 #define DEBUG_FIXME(fmt, args...) DEBUG_PRINT("[F]", fmt, ##args)
 
-#ifdef DEBUG_SPICE
+#if defined(DEBUG_SPICE) | defined(DEBUG_IVSHMEM)
   #define DEBUG_PROTO(fmt, args...) DEBUG_PRINT("[P]", fmt, ##args)
 #else
   #define DEBUG_PROTO(fmt, args...) do {} while(0)

client/ivshmem/ivshmem.c

@@ -0,0 +1,145 @@
+#include "ivshmem.h"
+
+#define DEBUG
+#define DEBUG_IVSHMEM
+#include "debug.h"
+
+#include <string.h>
+#include <unistd.h>
+#include <stdbool.h>
+#include <stdint.h>
+
+#include <sys/socket.h>
+#include <sys/un.h>
+
+struct IVSHMEM
+{
+  bool connected;
+  int  socket;
+};
+
+struct IVSHMEM ivshmem =
+{
+  .connected = false,
+  .socket    = -1
+};
+
+// ============================================================================
+// internal functions
+
+void ivshmem_cleanup();
+bool ivshmem_read(void * buffer, const ssize_t size);
+
+// ============================================================================
+
+bool ivshmem_connect(const char * unix_socket)
+{
+  ivshmem.socket = socket(AF_UNIX, SOCK_STREAM, 0);
+  if (ivshmem.socket < 0)
+  {
+    DEBUG_ERROR("socket creation failed");
+    return false;
+  }
+
+  struct sockaddr_un addr;
+  addr.sun_family = AF_UNIX;
+  strncpy(addr.sun_path, unix_socket, sizeof(addr.sun_path));
+
+  if (connect(ivshmem.socket, (struct sockaddr *)&addr, sizeof(struct sockaddr_un)) < 0)
+  {
+    DEBUG_ERROR("socket connect failed");
+    ivshmem_cleanup();
+    return false;
+  }
+
+  ivshmem.connected = true;
+
+  struct IVSHMEMInit init;
+  if (!ivshmem_read(&init.version, sizeof(init.version)))
+  {
+    DEBUG_ERROR("read protocol version failed");
+    ivshmem_cleanup();
+    return false;
+  }
+
+  if (init.version != 0)
+  {
+    DEBUG_ERROR("unsupported protocol version %ld", init.version);
+    ivshmem_cleanup();
+    return false;
+  }
+
+  if (!ivshmem_read(&init.clientID, sizeof(init.clientID)))
+  {
+    DEBUG_ERROR("read client id failed");
+    ivshmem_cleanup();
+    return false;
+  }
+
+  if (!ivshmem_read(&init.unused, sizeof(init.unused)))
+  {
+    DEBUG_ERROR("read unused failed");
+    ivshmem_cleanup();
+    return false;
+  }
+
+  if (!ivshmem_read(&init.sharedFD, sizeof(init.sharedFD)))
+  {
+    DEBUG_ERROR("read shared memory file descriptor failed");
+    ivshmem_cleanup();
+    return false;
+  }
+
+  DEBUG_PROTO("Protocol : %ld", init.version );
+  DEBUG_PROTO("Client ID: %ld", init.clientID);
+  DEBUG_PROTO("Unused   : %ld", init.unused  );
+  DEBUG_PROTO("Shared FD: %ld", init.sharedFD);
+
+  return true;
+}
+
+// ============================================================================
+
+void ivshmem_cleanup()
+{
+  if (ivshmem.socket >= 0)
+  {
+    close(ivshmem.socket);
+    ivshmem.socket = -1;
+  }
+
+  ivshmem.connected = false;
+}
+
+// ============================================================================
+
+void ivshmem_close()
+{
+  if (!ivshmem.connected)
+  {
+    DEBUG_WARN("socket not connected");
+    return;
+  }
+
+  ivshmem_cleanup();
+}
+
+// ============================================================================
+
+bool ivshmem_read(void * buffer, const ssize_t size)
+{
+  if (!ivshmem.connected)
+  {
+    DEBUG_ERROR("not connected");
+    return false;
+  }
+
+  ssize_t len = read(ivshmem.socket, buffer, size);
+  if (len != size)
+  {
+    DEBUG_ERROR("incomplete read");
+    return false;
+  }
+
+  return true;
+}

client/ivshmem/ivshmem.h

@@ -0,0 +1,13 @@
+#include <stdint.h>
+#include <stdbool.h>
+
+struct IVSHMEMInit
+{
+   int64_t version;
+   int64_t clientID;
+   int64_t unused;
+   int64_t sharedFD;
+};
+
+bool ivshmem_connect(const char * unix_socket);
+void ivshmem_close();