Archipelago » qemu

/*

 * Virtio 9p  xattr callback

 *

 * Copyright IBM, Corp. 2010

 *

 * Authors:

 * Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

 *

 * This work is licensed under the terms of the GNU GPL, version 2.  See

 * the COPYING file in the top-level directory.

 *

 */

#include "virtio.h"

#include "virtio-9p.h"

#include "fsdev/file-op-9p.h"

#include "virtio-9p-xattr.h"

static XattrOperations *get_xattr_operations(XattrOperations **h,

                                             const char *name)

{

    XattrOperations *xops;

    for (xops = *(h)++; xops != NULL; xops = *(h)++) {

        if (!strncmp(name, xops->name, strlen(xops->name))) {

            return xops;

        }

    }

    return NULL;

}

ssize_t v9fs_get_xattr(FsContext *ctx, const char *path,

                       const char *name, void *value, size_t size)

{

    XattrOperations *xops = get_xattr_operations(ctx->xops, name);

    if (xops) {

        return xops->getxattr(ctx, path, name, value, size);

    }

    errno = -EOPNOTSUPP;

    return -1;

}

ssize_t pt_listxattr(FsContext *ctx, const char *path,

                     char *name, void *value, size_t size)

{

    int name_size = strlen(name) + 1;

    if (!value) {

        return name_size;

    }

    if (size < name_size) {

        errno = ERANGE;

        return -1;

    }

    strncpy(value, name, name_size);

    return name_size;

}

/*

 * Get the list and pass to each layer to find out whether

 * to send the data or not

 */

ssize_t v9fs_list_xattr(FsContext *ctx, const char *path,

                        void *value, size_t vsize)

{

    ssize_t size = 0;

    void *ovalue = value;

    XattrOperations *xops;

    char *orig_value, *orig_value_start;

    ssize_t xattr_len, parsed_len = 0, attr_len;

    /* Get the actual len */

    xattr_len = llistxattr(rpath(ctx, path), value, 0);

    if (xattr_len <= 0) {

        return xattr_len;

    }

    /* Now fetch the xattr and find the actual size */

    orig_value = qemu_malloc(xattr_len);

    xattr_len = llistxattr(rpath(ctx, path), orig_value, xattr_len);

    /* store the orig pointer */

    orig_value_start = orig_value;

    while (xattr_len > parsed_len) {

        xops = get_xattr_operations(ctx->xops, orig_value);

        if (!xops) {

            goto next_entry;

        }

        if (!value) {

            size += xops->listxattr(ctx, path, orig_value, value, vsize);

        } else {

            size = xops->listxattr(ctx, path, orig_value, value, vsize);

            if (size < 0) {

                goto err_out;

            }

            value += size;

            vsize -= size;

        }

next_entry:

        /* Got the next entry */

        attr_len = strlen(orig_value) + 1;

        parsed_len += attr_len;

        orig_value += attr_len;

    }

    if (value) {

        size = value - ovalue;

    }

err_out:

    qemu_free(orig_value_start);

    return size;

}

int v9fs_set_xattr(FsContext *ctx, const char *path, const char *name,

                   void *value, size_t size, int flags)

{

    XattrOperations *xops = get_xattr_operations(ctx->xops, name);

    if (xops) {

        return xops->setxattr(ctx, path, name, value, size, flags);

    }

    errno = -EOPNOTSUPP;

    return -1;

}

int v9fs_remove_xattr(FsContext *ctx,

                      const char *path, const char *name)

{

    XattrOperations *xops = get_xattr_operations(ctx->xops, name);

    if (xops) {

        return xops->removexattr(ctx, path, name);

    }

    errno = -EOPNOTSUPP;

    return -1;

}

XattrOperations *mapped_xattr_ops[] = {

    &mapped_user_xattr,

    &mapped_pacl_xattr,

    &mapped_dacl_xattr,

    NULL,

};

XattrOperations *passthrough_xattr_ops[] = {

    &passthrough_user_xattr,

    &passthrough_acl_xattr,

    NULL,

};

/* for .user none model should be same as passthrough */

XattrOperations *none_xattr_ops[] = {

    &passthrough_user_xattr,

    &none_acl_xattr,

    NULL,

};