reader: track read_filter "can_seek" with a flag

Currently we the ::seek callback can be either NULL or client_seek_proxy.

Since we already explicitly use the latter, instead of ::seek just drop
the function pointer all together, in favour of a simple flag.

Alternatively one could use a ARCHIVE_FILTER_NONE check.

Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>

diff --git a/libarchive/archive_read.c b/libarchive/archive_read.c
index 23526057931b9c133e8200375e74802c983aa6aa..0a749c81d1f5f2c91724bd4ed3e3dca133b8788e 100644 (file)
--- a/libarchive/archive_read.c
+++ b/libarchive/archive_read.c
@@ -489,11 +489,11 @@ archive_read_open1(struct archive *_a)
        filter->open = client_open_proxy;
        filter->read = client_read_proxy;
        filter->skip = client_skip_proxy;
-       filter->seek = client_seek_proxy;
        filter->close = client_close_proxy;
        filter->sswitch = client_switch_proxy;
        filter->name = "none";
        filter->code = ARCHIVE_FILTER_NONE;
+       filter->can_seek = 1;
 
        a->client.dataset[0].begin_position = 0;
        if (!a->filter || !a->bypass_filter_bidding)
@@ -1633,7 +1633,7 @@ __archive_read_filter_seek(struct archive_read_filter *filter, int64_t offset,
 
        if (filter->closed || filter->fatal)
                return (ARCHIVE_FATAL);
-       if (filter->seek == NULL)
+       if (filter->can_seek == 0)
                return (ARCHIVE_FAILED);
 
        client = &(filter->archive->client);

diff --git a/libarchive/archive_read_private.h b/libarchive/archive_read_private.h
index ff6c336c9f51130a5446b6a476c75cc519361aa1..b555956699a1482db6833429db26318568a1592d 100644 (file)
--- a/libarchive/archive_read_private.h
+++ b/libarchive/archive_read_private.h
@@ -93,8 +93,6 @@ struct archive_read_filter {
        ssize_t (*read)(struct archive_read_filter *, const void **);
        /* Skip forward this many bytes. */
        int64_t (*skip)(struct archive_read_filter *self, int64_t request);
-       /* Seek to an absolute location. */
-       int64_t (*seek)(struct archive_read_filter *self, int64_t offset, int whence);
        /* Close (just this filter) and free(self). */
        int (*close)(struct archive_read_filter *self);
        /* Function that handles switching from reading one block to the next/prev */
@@ -106,6 +104,7 @@ struct archive_read_filter {
 
        const char      *name;
        int              code;
+       int              can_seek;
 
        /* Used by reblocking logic. */
        char            *buffer;