[06/10] vmdk: make vmdk_snapshot_create return -errno

diff --git a/block/vmdk.c b/block/vmdk.c
index 5b1d197..67a690e 100644
--- a/block/vmdk.c
+++ b/block/vmdk.c
@@ -187,6 +187,7 @@  static int vmdk_is_cid_valid(BlockDriverState *bs)
 static int vmdk_snapshot_create(const char *filename, const char *backing_file)
 {
     int snp_fd, p_fd;
+    int ret;
     uint32_t p_cid;
     char *p_name, *gd_buf, *rgd_buf;
     const char *real_filename, *temp_str;
@@ -211,35 +212,49 @@  static int vmdk_snapshot_create(const char *filename, const char *backing_file)

     snp_fd = open(filename, O_RDWR | O_CREAT | O_TRUNC | O_BINARY | O_LARGEFILE, 0644);
     if (snp_fd < 0)
-        return -1;
+        return -errno;
     p_fd = open(backing_file, O_RDONLY | O_BINARY | O_LARGEFILE);
     if (p_fd < 0) {
         close(snp_fd);
-        return -1;
+        return -errno;
     }

     /* read the header */
-    if (lseek(p_fd, 0x0, SEEK_SET) == -1)
+    if (lseek(p_fd, 0x0, SEEK_SET) == -1) {
+        ret = -errno;
         goto fail;
-    if (read(p_fd, hdr, HEADER_SIZE) != HEADER_SIZE)
+    }
+    if (read(p_fd, hdr, HEADER_SIZE) != HEADER_SIZE) {
+        ret = -errno;
         goto fail;
+    }

     /* write the header */
-    if (lseek(snp_fd, 0x0, SEEK_SET) == -1)
+    if (lseek(snp_fd, 0x0, SEEK_SET) == -1) {
+        ret = -errno;
         goto fail;
-    if (write(snp_fd, hdr, HEADER_SIZE) == -1)
+    }
+    if (write(snp_fd, hdr, HEADER_SIZE) == -1) {
+        ret = -errno;
         goto fail;
+    }

     memset(&header, 0, sizeof(header));
     memcpy(&header,&hdr[4], sizeof(header)); // skip the VMDK4_MAGIC

-    if (ftruncate(snp_fd, header.grain_offset << 9))
+    if (ftruncate(snp_fd, header.grain_offset << 9)) {
+        ret = -errno;
         goto fail;
+    }
     /* the descriptor offset = 0x200 */
-    if (lseek(p_fd, 0x200, SEEK_SET) == -1)
+    if (lseek(p_fd, 0x200, SEEK_SET) == -1) {
+        ret = -errno;
         goto fail;
-    if (read(p_fd, p_desc, DESC_SIZE) != DESC_SIZE)
+    }
+    if (read(p_fd, p_desc, DESC_SIZE) != DESC_SIZE) {
+        ret = -errno;
         goto fail;
+    }

     if ((p_name = strstr(p_desc,"CID")) != NULL) {
         p_name += sizeof("CID");
@@ -258,10 +273,14 @@  static int vmdk_snapshot_create(const char *filename, const char *backing_file)
              (uint32_t)header.capacity, real_filename);

     /* write the descriptor */
-    if (lseek(snp_fd, 0x200, SEEK_SET) == -1)
+    if (lseek(snp_fd, 0x200, SEEK_SET) == -1) {
+        ret = -errno;
         goto fail;
-    if (write(snp_fd, s_desc, strlen(s_desc)) == -1)
+    }
+    if (write(snp_fd, s_desc, strlen(s_desc)) == -1) {
+        ret = -errno;
         goto fail;
+    }

     gd_offset = header.gd_offset * SECTOR_SIZE;     // offset of GD table
     rgd_offset = header.rgd_offset * SECTOR_SIZE;   // offset of RGD table
@@ -271,33 +290,51 @@  static int vmdk_snapshot_create(const char *filename, const char *backing_file)
      * 512 GTE per GT, each GTE points to grain
      */
     gt_size = (int64_t)header.num_gtes_per_gte * header.granularity * SECTOR_SIZE;
-    if (!gt_size)
+    if (!gt_size) {
+        ret = -EINVAL;
         goto fail;
+    }
     gde_entries = (uint32_t)(capacity / gt_size);  // number of gde/rgde
     gd_size = gde_entries * sizeof(uint32_t);

     /* write RGD */
     rgd_buf = qemu_malloc(gd_size);
-    if (lseek(p_fd, rgd_offset, SEEK_SET) == -1)
+    if (lseek(p_fd, rgd_offset, SEEK_SET) == -1) {
+        ret = -errno;
         goto fail_rgd;
-    if (read(p_fd, rgd_buf, gd_size) != gd_size)
+    }
+    if (read(p_fd, rgd_buf, gd_size) != gd_size) {
+        ret = -errno;
         goto fail_rgd;
-    if (lseek(snp_fd, rgd_offset, SEEK_SET) == -1)
+    }
+    if (lseek(snp_fd, rgd_offset, SEEK_SET) == -1) {
+        ret = -errno;
         goto fail_rgd;
-    if (write(snp_fd, rgd_buf, gd_size) == -1)
+    }
+    if (write(snp_fd, rgd_buf, gd_size) == -1) {
+        ret = -errno;
         goto fail_rgd;
+    }
     qemu_free(rgd_buf);

     /* write GD */
     gd_buf = qemu_malloc(gd_size);
-    if (lseek(p_fd, gd_offset, SEEK_SET) == -1)
+    if (lseek(p_fd, gd_offset, SEEK_SET) == -1) {
+        ret = -errno;
         goto fail_gd;
-    if (read(p_fd, gd_buf, gd_size) != gd_size)
+    }
+    if (read(p_fd, gd_buf, gd_size) != gd_size) {
+        ret = -errno;
         goto fail_gd;
-    if (lseek(snp_fd, gd_offset, SEEK_SET) == -1)
+    }
+    if (lseek(snp_fd, gd_offset, SEEK_SET) == -1) {
+        ret = -errno;
         goto fail_gd;
-    if (write(snp_fd, gd_buf, gd_size) == -1)
+    }
+    if (write(snp_fd, gd_buf, gd_size) == -1) {
+        ret = -errno;
         goto fail_gd;
+    }
     qemu_free(gd_buf);

     close(p_fd);
@@ -311,7 +348,7 @@  static int vmdk_snapshot_create(const char *filename, const char *backing_file)
     fail:
     close(p_fd);
     close(snp_fd);
-    return -1;
+    return ret;
 }

 static void vmdk_parent_close(BlockDriverState *bs)