On Sat, 16 Jun 2018 20:56:48 -0400
Keno Fischer wrote:
> On darwin d_seekoff exists, but is optional and does not seem to
> be commonly used by file systems. Use `telldir` instead to obtain
> the seek offset.
>
Thinking again about this one, I guess we also need our own
type for dirent and per-OS qemu_readdir(), and have the Darwin
version to call telldir() directly.
> Signed-off-by: Keno Fischer
> ---
> hw/9pfs/9p-synth.c | 2 ++
> hw/9pfs/9p.c | 36
> 2 files changed, 34 insertions(+), 4 deletions(-)
>
> diff --git a/hw/9pfs/9p-synth.c b/hw/9pfs/9p-synth.c
> index eb68b42..a312f8c 100644
> --- a/hw/9pfs/9p-synth.c
> +++ b/hw/9pfs/9p-synth.c
> @@ -221,7 +221,9 @@ static void synth_direntry(V9fsSynthNode *node,
> {
> strcpy(entry->d_name, node->name);
> entry->d_ino = node->attr->inode;
> +#ifndef CONFIG_DARWIN
> entry->d_off = off + 1;
> +#endif
> }
>
> static struct dirent *synth_get_dentry(V9fsSynthNode *dir,
> diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c
> index 8e6b908..06139c9 100644
> --- a/hw/9pfs/9p.c
> +++ b/hw/9pfs/9p.c
> @@ -1738,6 +1738,25 @@ static int v9fs_xattr_read(V9fsState *s, V9fsPDU *pdu,
> V9fsFidState *fidp,
> return offset;
> }
>
> +/**
> + * Get the seek offset of a dirent. If not available from the structure
> itself,
> + * obtain it by calling telldir.
> + */
> +static int v9fs_dent_telldir(V9fsPDU *pdu, V9fsFidState *fidp,
> + struct dirent *dent)
> +{
> +#ifdef CONFIG_DARWIN
> +/*
> + * Darwin has d_seekoff, which appears to function similarly to d_off.
> + * However, it does not appear to be supported on all file systems,
> + * so use telldir for correctness.
> + */
> +return v9fs_co_telldir(pdu, fidp);
> +#else
> +return dent->d_off;
> +#endif
> +}
> +
> static int coroutine_fn v9fs_do_readdir_with_stat(V9fsPDU *pdu,
>V9fsFidState *fidp,
>uint32_t max_count)
> @@ -1801,7 +1820,11 @@ static int coroutine_fn
> v9fs_do_readdir_with_stat(V9fsPDU *pdu,
> count += len;
> v9fs_stat_free();
> v9fs_path_free();
> -saved_dir_pos = dent->d_off;
> +saved_dir_pos = v9fs_dent_telldir(pdu, fidp, dent);
> +if (saved_dir_pos < 0) {
> +err = saved_dir_pos;
> +break;
> +}
> }
>
> v9fs_readdir_unlock(>fs.dir);
> @@ -1915,7 +1938,7 @@ static int coroutine_fn v9fs_do_readdir(V9fsPDU *pdu,
> V9fsFidState *fidp,
> V9fsString name;
> int len, err = 0;
> int32_t count = 0;
> -off_t saved_dir_pos;
> +off_t saved_dir_pos, off;
> struct dirent *dent;
>
> /* save the directory position */
> @@ -1951,10 +1974,15 @@ static int coroutine_fn v9fs_do_readdir(V9fsPDU *pdu,
> V9fsFidState *fidp,
> /* Fill the other fields with dummy values */
> qid.type = 0;
> qid.version = 0;
> +off = v9fs_dent_telldir(pdu, fidp, dent);
> +if (off < 0) {
> +err = off;
> +break;
> +}
>
> /* 11 = 7 + 4 (7 = start offset, 4 = space for storing count) */
> len = pdu_marshal(pdu, 11 + count, "Qqbs",
> - , dent->d_off,
> + , off,
>dent->d_type, );
>
> v9fs_readdir_unlock(>fs.dir);
> @@ -1966,7 +1994,7 @@ static int coroutine_fn v9fs_do_readdir(V9fsPDU *pdu,
> V9fsFidState *fidp,
> }
> count += len;
> v9fs_string_free();
> -saved_dir_pos = dent->d_off;
> +saved_dir_pos = off;
> }
>
> v9fs_readdir_unlock(>fs.dir);
