restore: deal with holes and set i_size correctly

This changes restore to set the i_size of the files it
copies out based on the size in the inode.  It also changes
it to skip over holes.

Signed-off-by: Chris Mason <chris.mason@oracle.com>

diff --git a/Makefile b/Makefile
index e85c726..a5024f1 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,6 @@
 CC = gcc
 AM_CFLAGS = -Wall -D_FILE_OFFSET_BITS=64 -D_FORTIFY_SOURCE=2
-CFLAGS = -g -Os
+CFLAGS = -g -O0
 objects = ctree.o disk-io.o radix-tree.o extent-tree.o print-tree.o \
          root-tree.o dir-item.o file-item.o inode-item.o \
          inode-map.o crc32c.o rbtree.o extent-cache.o extent_io.o \

diff --git a/restore.c b/restore.c
index c20f4e1..250c9d3 100644 (file)
--- a/restore.c
+++ b/restore.c
@@ -204,6 +204,10 @@ static int copy_one_extent(struct btrfs_root *root, int fd,
        ram_size = btrfs_file_extent_ram_bytes(leaf, fi);
        size_left = disk_size;
 
+       /* we found a hole */
+       if (disk_size == 0)
+               return 0;
+
        inbuf = malloc(disk_size);
        if (!inbuf) {
                fprintf(stderr, "No memory\n");
@@ -258,7 +262,7 @@ again:
                                      pos+total);
                        if (done < 0) {
                                free(inbuf);
-                               fprintf(stderr, "Error writing: %d\n", errno);
+                               fprintf(stderr, "Error writing: %d %s\n", errno, strerror(errno));
                                return -1;
                        }
                        total += done;
@@ -278,7 +282,7 @@ again:
                done = pwrite(fd, outbuf+total, ram_size-total, pos+total);
                if (done < 0) {
                        free(outbuf);
-                       fprintf(stderr, "Error writing: %d\n", errno);
+                       fprintf(stderr, "Error writing: %d %s\n", errno, strerror(errno));
                        return -1;
                }
                total += done;
@@ -314,11 +318,13 @@ static int copy_file(struct btrfs_root *root, int fd, struct btrfs_key *key,
        struct extent_buffer *leaf;
        struct btrfs_path *path;
        struct btrfs_file_extent_item *fi;
+       struct btrfs_inode_item *inode_item;
        struct btrfs_key found_key;
        int ret;
        int extent_type;
        int compression;
        int loops = 0;
+       u64 found_size = 0;
 
        path = btrfs_alloc_path();
        if (!path) {
@@ -327,6 +333,14 @@ static int copy_file(struct btrfs_root *root, int fd, struct btrfs_key *key,
        }
        path->skip_locking = 1;
 
+       ret = btrfs_lookup_inode(NULL, root, path, key, 0);
+       if (ret == 0) {
+               inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
+                                   struct btrfs_inode_item);
+               found_size = btrfs_inode_size(path->nodes[0], inode_item);
+       }
+       btrfs_release_path(root, path);
+
        key->offset = 0;
        key->type = BTRFS_EXTENT_DATA_KEY;
 
@@ -370,6 +384,7 @@ static int copy_file(struct btrfs_root *root, int fd, struct btrfs_key *key,
                                } else if (ret) {
                                        /* No more leaves to search */
                                        btrfs_free_path(path);
+                                       goto set_size;
                                        return 0;
                                }
                                leaf = path->nodes[0];
@@ -415,6 +430,9 @@ next:
        }
 
        btrfs_free_path(path);
+set_size:
+       if (found_size)
+               ftruncate(fd, (loff_t)found_size);
        return 0;
 }