[PATCH v5 2/8] libxl: libxl__device_disk_local_attach return a new libxl_device_disk

[Stefano Stabellini <stefano.stabellini@eu.citrix.com>]

Introduce a new libxl_device_disk** parameter to
libxl__device_disk_local_attach, the parameter is allocated on the gc by
libxl__device_disk_local_attach. It is going to fill it with
informations about the new locally attached disk.  The new
libxl_device_disk should be passed to libxl_device_disk_local_detach
afterwards.

Changes in v5:
- rename disk to in_disk;
- rename tmpdisk to disk;
- copy disk to new_disk only on success;
- remove check on libxl__zalloc success.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
---
 tools/libxl/libxl_bootloader.c |   10 +++++-----
 tools/libxl/libxl_internal.c   |   20 ++++++++++++++------
 tools/libxl/libxl_internal.h   |    3 ++-
 3 files changed, 21 insertions(+), 12 deletions(-)

diff --git a/tools/libxl/libxl_bootloader.c b/tools/libxl/libxl_bootloader.c
index 977c6d3..83cac78 100644
--- a/tools/libxl/libxl_bootloader.c
+++ b/tools/libxl/libxl_bootloader.c
@@ -330,6 +330,7 @@ int libxl_run_bootloader(libxl_ctx *ctx,
     char *fifo = NULL;
     char *diskpath = NULL;
     char **args = NULL;
+    libxl_device_disk *tmpdisk = NULL;
 
     char tempdir_template[] = "/var/run/libxl/bl.XXXXXX";
     char *tempdir;
@@ -386,8 +387,9 @@ int libxl_run_bootloader(libxl_ctx *ctx,
         goto out_close;
     }
 
-    diskpath = libxl__device_disk_local_attach(gc, disk);
+    diskpath = libxl__device_disk_local_attach(gc, disk, &tmpdisk);
     if (!diskpath) {
+        rc = ERROR_FAIL;
         goto out_close;
     }
 
@@ -452,10 +454,8 @@ int libxl_run_bootloader(libxl_ctx *ctx,
 
     rc = 0;
 out_close:
-    if (diskpath) {
-        libxl__device_disk_local_detach(gc, disk);
-        free(diskpath);
-    }
+    if (tmpdisk)
+        libxl__device_disk_local_detach(gc, tmpdisk);
     if (fifo_fd > -1)
         close(fifo_fd);
     if (bootloader_fd > -1)
diff --git a/tools/libxl/libxl_internal.c b/tools/libxl/libxl_internal.c
index fc771ff..55dc55c 100644
--- a/tools/libxl/libxl_internal.c
+++ b/tools/libxl/libxl_internal.c
@@ -323,12 +323,21 @@ out:
     return rc;
 }
 
-char * libxl__device_disk_local_attach(libxl__gc *gc, libxl_device_disk *disk)
+char * libxl__device_disk_local_attach(libxl__gc *gc,
+        const libxl_device_disk *in_disk,
+        libxl_device_disk **new_disk)
 {
     libxl_ctx *ctx = gc->owner;
     char *dev = NULL;
-    char *ret = NULL;
     int rc;
+    libxl_device_disk *disk = libxl__zalloc(gc, sizeof(libxl_device_disk));
+
+    memcpy(disk, in_disk, sizeof(libxl_device_disk));
+    if (in_disk->pdev_path != NULL)
+        disk->pdev_path = libxl__strdup(gc, in_disk->pdev_path);
+    if (in_disk->script != NULL)
+        disk->script = libxl__strdup(gc, in_disk->script);
+    disk->vdev = NULL;
 
     rc = libxl__device_disk_setdefault(gc, disk);
     if (rc) goto out;
@@ -368,7 +377,7 @@ char * libxl__device_disk_local_attach(libxl__gc *gc, libxl_device_disk *disk)
                 break;
             }
             LIBXL__LOG(ctx, LIBXL__LOG_DEBUG, "locally attaching qdisk %s\n",
-                       disk->pdev_path);
+                       in_disk->pdev_path);
             dev = disk->pdev_path;
             break;
         default:
@@ -378,9 +387,8 @@ char * libxl__device_disk_local_attach(libxl__gc *gc, libxl_device_disk *disk)
     }
 
  out:
-    if (dev != NULL)
-        ret = strdup(dev);
-    return ret;
+    *new_disk = disk;
+    return dev;
 }
 
 int libxl__device_disk_local_detach(libxl__gc *gc, libxl_device_disk *disk)
diff --git a/tools/libxl/libxl_internal.h b/tools/libxl/libxl_internal.h
index ddd6a37..965d13b 100644
--- a/tools/libxl/libxl_internal.h
+++ b/tools/libxl/libxl_internal.h
@@ -1008,7 +1008,8 @@ _hidden void libxl__device_destroy_tapdisk(libxl__gc *gc, char *be_path);
  * a device.
  */
 _hidden char * libxl__device_disk_local_attach(libxl__gc *gc,
-        libxl_device_disk *disk);
+        const libxl_device_disk *in_disk,
+        libxl_device_disk **new_disk);
 _hidden int libxl__device_disk_local_detach(libxl__gc *gc,
         libxl_device_disk *disk);
 
-- 
1.7.2.5