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[wimlib] / src / lookup_table.h

diff --git a/src/lookup_table.h b/src/lookup_table.h
index 633c874e17d1f7d1fc8ec03e6c41f722ddd135ff..83796aae2d8bca57cf4566de9467755444da9cfa 100644 (file)
--- a/src/lookup_table.h
+++ b/src/lookup_table.h
@@ -40,7 +40,7 @@ struct ntfs_location {
        tchar *path;
        utf16lechar *stream_name;
        u16 stream_name_nchars;
-       struct _ntfs_volume **ntfs_vol_p;
+       struct _ntfs_volume *ntfs_vol;
        bool is_reparse_point;
 };
 #endif
@@ -135,9 +135,13 @@ struct wim_lookup_table_entry {
         */
        u16 part_number;
 
-       /* See enum resource_location above */
+       /* One of the `enum resource_location' values documented above. */
        u16 resource_location : 5;
+
+       /* 1 if this stream is a unique size (only set while writing streams). */
        u8 unique_size : 1;
+
+       /* 1 if this stream had a SHA1-message digest calculated for it yet? */
        u8 unhashed : 1;
 
        /* (On-disk field)
@@ -159,18 +163,22 @@ struct wim_lookup_table_entry {
                 * table. */
                size_t hash_short;
 
-               /* Unhashed entries only (unhashed == 1): this points directly
-                * to the pointer to this 'struct wim_lookup_table_entry'
-                * contained in a 'struct wim_ads_entry' or 'struct wim_inode'.
-                * */
-               struct wim_lookup_table_entry **my_ptr;
+               /* Unhashed entries only (unhashed == 1): these variables make
+                * it possible to find the pointer to this 'struct
+                * wim_lookup_table_entry' contained in either 'struct
+                * wim_ads_entry' or 'struct wim_inode'.  There can be at most 1
+                * such pointer, as we can only join duplicate streams after
+                * they have been hashed.  */
+               struct {
+                       struct wim_inode *back_inode;
+                       u32 back_stream_id;
+               };
        };
 
        /* When a WIM file is written, out_refcnt starts at 0 and is incremented
-        * whenever the file resource pointed to by this lookup table entry
-        * needs to be written.  The file resource only need to be written when
-        * out_refcnt is nonzero, since otherwise it is not referenced by any
-        * dentries. */
+        * whenever the stream pointed to by this lookup table entry needs to be
+        * written.  The stream only need to be written when out_refcnt is
+        * nonzero, since otherwise it is not referenced by any dentries. */
        u32 out_refcnt;
 
        /* Pointers to somewhere where the stream is actually located.  See the
@@ -178,24 +186,25 @@ struct wim_lookup_table_entry {
        union {
                WIMStruct *wim;
                tchar *file_on_disk;
-               tchar *staging_file_name;
                void *attached_buffer;
+       #ifdef WITH_FUSE
+               tchar *staging_file_name;
+       #endif
        #ifdef WITH_NTFS_3G
                struct ntfs_location *ntfs_loc;
        #endif
        };
 
-       /* Pointer to inode that contains the opened file descriptors to
-        * this stream (valid iff resource_location ==
-        * RESOURCE_IN_STAGING_FILE) */
-       struct wim_inode *lte_inode;
-
+       /* Actual reference count to this stream (only used while
+        * verifying an image). */
        u32 real_refcnt;
 
        union {
-               #ifdef WITH_FUSE
+       #ifdef WITH_FUSE
+               /* Number of times this stream has been opened (used only during
+                * mounting) */
                u16 num_opened_fds;
-               #endif
+       #endif
 
                /* This field is used for the special hardlink or symlink image
                 * extraction mode.   In these mode, all identical files are linked
@@ -219,20 +228,17 @@ struct wim_lookup_table_entry {
 
                struct {
                        struct hlist_node hash_list_2;
+
                        struct list_head write_streams_list;
                };
        };
 
-       /* List of lookup table entries that correspond to streams that have
-        * been extracted to the staging directory when modifying a read-write
-        * mounted WIM.
-        *
-        * This field is also used to make other lists of lookup table entries.
-        * */
+       /* Temporary list fields */
        union {
                struct list_head unhashed_list;
-               struct list_head staging_list;
+               struct list_head swm_stream_list;
                struct list_head extraction_list;
+               struct list_head export_stream_list;
        };
 };
 
@@ -300,6 +306,7 @@ lookup_table_insert(struct wim_lookup_table *table, struct wim_lookup_table_entr
 static inline void
 lookup_table_unlink(struct wim_lookup_table *table, struct wim_lookup_table_entry *lte)
 {
+       wimlib_assert(!lte->unhashed);
        hlist_del(&lte->hash_list);
        wimlib_assert(table->num_entries != 0);
        table->num_entries--;
@@ -485,15 +492,21 @@ lookup_table_total_stream_size(struct wim_lookup_table *table);
 static inline void
 lookup_table_insert_unhashed(struct wim_lookup_table *table,
                             struct wim_lookup_table_entry *lte,
-                            struct wim_lookup_table_entry **my_ptr)
+                            struct wim_inode *back_inode,
+                            u32 back_stream_id)
 {
        lte->unhashed = 1;
+       lte->back_inode = back_inode;
+       lte->back_stream_id = back_stream_id;
        list_add_tail(&lte->unhashed_list, table->unhashed_streams);
-       lte->my_ptr = my_ptr;
-       *my_ptr = lte;
 }
 
-extern void
-free_lte_list(struct list_head *list);
+extern int
+hash_unhashed_stream(struct wim_lookup_table_entry *lte,
+                    struct wim_lookup_table *lookup_table,
+                    struct wim_lookup_table_entry **lte_ret);
+
+extern struct wim_lookup_table_entry **
+retrieve_lte_pointer(struct wim_lookup_table_entry *lte);
 
 #endif