From: Keno Fischer <k...@juliacomputing.com>
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 and inject it into d_seekoff, and create a
qemu_dirent_off helper to call it appropriately when appropriate.
Signed-off-by: Keno Fischer <k...@juliacomputing.com>
[Michael Roitzsch: - Rebase for NixOS]
Signed-off-by: Michael Roitzsch <reactorcont...@icloud.com>
[Will Cohen: - Adjust to pass testing
- Ensure that d_seekoff is filled using telldir
on darwin, and create qemu_dirent_off helper
to decide which to access]
[Fabian Franz: - Add telldir error handling for darwin]
[Will Cohen: - Ensure that telldir error handling uses
signed int]
Signed-off-by: Fabian Franz <fabianfranz....@gmail.com>
Signed-off-by: Will Cohen <wwco...@gmail.com>
---
hw/9pfs/9p-local.c | 9 +++++++++
hw/9pfs/9p-proxy.c | 16 +++++++++++++++-
hw/9pfs/9p-synth.c | 4 ++++
hw/9pfs/9p-util.h | 17 +++++++++++++++++
hw/9pfs/9p.c | 15 +++++++++++++--
hw/9pfs/codir.c | 7 +++++++
6 files changed, 65 insertions(+), 3 deletions(-)
diff --git a/hw/9pfs/9p-local.c b/hw/9pfs/9p-local.c
index 1a5e3eed73..7137a28109 100644
--- a/hw/9pfs/9p-local.c
+++ b/hw/9pfs/9p-local.c
@@ -559,6 +559,15 @@ static struct dirent *local_readdir(FsContext *ctx,
V9fsFidOpenState *fs)
again:
entry = readdir(fs->dir.stream);
+#ifdef CONFIG_DARWIN
+ int td;
+ td = telldir(fs->dir.stream);
+ /* If telldir fails, fail the entire readdir call */
+ if (td < 0) {
+ return NULL;
+ }
+ entry->d_seekoff = td;
+#endif
if (!entry) {
return NULL;
}
diff --git a/hw/9pfs/9p-proxy.c b/hw/9pfs/9p-proxy.c
index b1664080d8..8b4b5cf7dc 100644
--- a/hw/9pfs/9p-proxy.c
+++ b/hw/9pfs/9p-proxy.c
@@ -706,7 +706,21 @@ static off_t proxy_telldir(FsContext *ctx,
V9fsFidOpenState *fs)
static struct dirent *proxy_readdir(FsContext *ctx, V9fsFidOpenState *fs)
{
- return readdir(fs->dir.stream);
+ struct dirent *entry;
+ entry = readdir(fs->dir.stream);
+#ifdef CONFIG_DARWIN
+ if (!entry) {
+ return NULL;
+ }
+ int td;
+ td = telldir(fs->dir.stream);
+ /* If telldir fails, fail the entire readdir call */
+ if (td < 0) {
+ return NULL;
+ }
+ entry->d_seekoff = td;
+#endif
+ return entry;
}
static void proxy_seekdir(FsContext *ctx, V9fsFidOpenState *fs, off_t off)
diff --git a/hw/9pfs/9p-synth.c b/hw/9pfs/9p-synth.c
index 4a4a776d06..e264a03eef 100644
--- a/hw/9pfs/9p-synth.c
+++ b/hw/9pfs/9p-synth.c
@@ -222,7 +222,11 @@ static void synth_direntry(V9fsSynthNode *node,
{
strcpy(entry->d_name, node->name);
entry->d_ino = node->attr->inode;
+#ifdef CONFIG_DARWIN
+ entry->d_seekoff = off + 1;
+#else
entry->d_off = off + 1;
+#endif
}
static struct dirent *synth_get_dentry(V9fsSynthNode *dir,
diff --git a/hw/9pfs/9p-util.h b/hw/9pfs/9p-util.h
index 546f46dc7d..accbec9987 100644
--- a/hw/9pfs/9p-util.h
+++ b/hw/9pfs/9p-util.h
@@ -79,3 +79,20 @@ ssize_t fremovexattrat_nofollow(int dirfd, const char
*filename,
const char *name);
#endif
+
+
+/**
+ * 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 ensure it is manually injected earlier and call here when
+ * needed.
+ */
+
+inline off_t qemu_dirent_off(struct dirent *dent)
+{
+#ifdef CONFIG_DARWIN
+ return dent->d_seekoff;
+#else
+ return dent->d_off;
+#endif
+}
diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c
index 1563d7b7c6..cf694da354 100644
--- a/hw/9pfs/9p.c
+++ b/hw/9pfs/9p.c
@@ -27,6 +27,7 @@
#include "virtio-9p.h"
#include "fsdev/qemu-fsdev.h"
#include "9p-xattr.h"
+#include "9p-util.h"
#include "coth.h"
#include "trace.h"
#include "migration/blocker.h"
@@ -2281,7 +2282,11 @@ static int coroutine_fn
v9fs_do_readdir_with_stat(V9fsPDU *pdu,
count += len;
v9fs_stat_free(&v9stat);
v9fs_path_free(&path);
- saved_dir_pos = dent->d_off;
+ saved_dir_pos = qemu_dirent_off(dent);
+ if (saved_dir_pos < 0) {
+ err = saved_dir_pos;
+ break;
+ }
}
v9fs_readdir_unlock(&fidp->fs.dir);
@@ -2420,6 +2425,7 @@ static int coroutine_fn v9fs_do_readdir(V9fsPDU *pdu,
V9fsFidState *fidp,
V9fsString name;
int len, err = 0;
int32_t count = 0;
+ off_t off;
struct dirent *dent;
struct stat *st;
struct V9fsDirEnt *entries = NULL;
@@ -2480,12 +2486,17 @@ static int coroutine_fn v9fs_do_readdir(V9fsPDU *pdu,
V9fsFidState *fidp,
qid.version = 0;
}
+ off = qemu_dirent_off(dent);
+ if (off < 0) {
+ err = off;
+ break;
+ }
v9fs_string_init(&name);
v9fs_string_sprintf(&name, "%s", dent->d_name);
/* 11 = 7 + 4 (7 = start offset, 4 = space for storing count) */
len = pdu_marshal(pdu, 11 + count, "Qqbs",
- &qid, dent->d_off,
+ &qid, off,
dent->d_type, &name);
v9fs_string_free(&name);
diff --git a/hw/9pfs/codir.c b/hw/9pfs/codir.c
index 032cce04c4..fac6759a64 100644
--- a/hw/9pfs/codir.c
+++ b/hw/9pfs/codir.c
@@ -167,7 +167,14 @@ static int do_readdir_many(V9fsPDU *pdu, V9fsFidState
*fidp,
}
size += len;
+ /* This conditional statement is identical in
+ * function to qemu_dirent_off, described in 9p-util.h,
+ * since that header cannot be included here. */
+#ifdef CONFIG_DARWIN
+ saved_dir_pos = dent->d_seekoff;
+#else
saved_dir_pos = dent->d_off;
+#endif
}
/* restore (last) saved position */
--
2.32.0 (Apple Git-132)
