Misc fixes for vfu_ctx_try_attach() and vfu_realize_ctx() (#175)

Misc changes for vfu_ctx_try_attach()
* Rename to vfu_attach_ctx()
* Removed call to vfu_realize_ctx(), should be called separately
* Now vfu_attach_ctx() must also be called for blocking ctx.

Misc changes for vfu_realize_ctx()
* Made calling vfu_realize_ctx() mandatory
* vfu_ctx_drive() and vfu_poll_ctx() returns EINVAL if the device is not
realized.
* Renamed vfu_ctx->ready to vfu_ctx->realized

Added unit test for vfu_attach_ctx() and vfu_realize_ctx()

Signed-off-by: Swapnil Ingle <swapnil.ingle@nutanix.com>
Reviewed-by: Thanos Makatos <thanos.makatos@nutanix.com>

3 files changed, 30 insertions, 0 deletions

diff --git a/samples/gpio-pci-idio-16.c b/samples/gpio-pci-idio-16.c
index e786d43..a957117 100644
--- a/samples/gpio-pci-idio-16.c
+++ b/samples/gpio-pci-idio-16.c
@@ -133,6 +133,16 @@ main(int argc, char *argv[])
         err(EXIT_FAILURE, "failed to setup irq counts");
     }
 
+    ret = vfu_realize_ctx(vfu_ctx);
+    if (ret < 0) {
+        err(EXIT_FAILURE, "failed to realize device");
+    }
+
+    ret = vfu_attach_ctx(vfu_ctx);
+    if (ret < 0) {
+        err(EXIT_FAILURE, "failed to attach device");
+    }
+
     ret = vfu_ctx_drive(vfu_ctx);
     if (ret != 0) {
         if (ret != -ENOTCONN && ret != -EINTR) {
diff --git a/samples/null.c b/samples/null.c
index fda260e..7944e30 100644
--- a/samples/null.c
+++ b/samples/null.c
@@ -62,6 +62,16 @@ static void* null_drive(void *arg)
         fprintf(stderr, "failed to enable cancel type: %s\n", strerror(ret));
         return NULL;
     }
+    ret = vfu_realize_ctx(vfu_ctx);
+    if (ret < 0) {
+        fprintf(stderr, "failed to realize device\n");
+        return NULL;
+    }
+    ret = vfu_attach_ctx(vfu_ctx);
+    if (ret < 0) {
+        fprintf(stderr, "failed to attach device\n");
+        return NULL;
+    }
     printf("starting device emulation\n");
     vfu_ctx_drive(vfu_ctx);
     return NULL;
diff --git a/samples/server.c b/samples/server.c
index 25bf101..be3c4d9 100644
--- a/samples/server.c
+++ b/samples/server.c
@@ -485,6 +485,16 @@ int main(int argc, char *argv[])
         err(EXIT_FAILURE, "failed to allocate migration data");
     }
 
+    ret = vfu_realize_ctx(vfu_ctx);
+    if (ret < 0) {
+        err(EXIT_FAILURE, "failed to realize device");
+    }
+
+    ret = vfu_attach_ctx(vfu_ctx);
+    if (ret < 0) {
+        err(EXIT_FAILURE, "failed to attach device");
+    }
+
     do {
         ret = vfu_ctx_drive(vfu_ctx);
         if (ret == -EINTR) {