iconv.c

UNIX/LINUX下面的用户文件系统

    char *newpath;
    int err = iconv_convpath(ic, path, &newpath, 0);
    if (!err) {
        err = fuse_fs_utimens(ic->next, newpath, ts);
        free(newpath);
    }
    return err;
}

static int iconv_create(const char *path, mode_t mode,
                        struct fuse_file_info *fi)
{
    struct iconv *ic = iconv_get();
    char *newpath;
    int err = iconv_convpath(ic, path, &newpath, 0);
    if (!err) {
        err = fuse_fs_create(ic->next, newpath, mode, fi);
        free(newpath);
    }
    return err;
}

static int iconv_open_file(const char *path, struct fuse_file_info *fi)
{
    struct iconv *ic = iconv_get();
    char *newpath;
    int err = iconv_convpath(ic, path, &newpath, 0);
    if (!err) {
        err = fuse_fs_open(ic->next, newpath, fi);
        free(newpath);
    }
    return err;
}

static int iconv_read(const char *path, char *buf, size_t size, off_t offset,
                    struct fuse_file_info *fi)
{
    struct iconv *ic = iconv_get();
    char *newpath;
    int err = iconv_convpath(ic, path, &newpath, 0);
    if (!err) {
        err = fuse_fs_read(ic->next, newpath, buf, size, offset, fi);
        free(newpath);
    }
    return err;
}

static int iconv_write(const char *path, const char *buf, size_t size,
                       off_t offset, struct fuse_file_info *fi)
{
    struct iconv *ic = iconv_get();
    char *newpath;
    int err = iconv_convpath(ic, path, &newpath, 0);
    if (!err) {
        err = fuse_fs_write(ic->next, newpath, buf, size, offset, fi);
        free(newpath);
    }
    return err;
}

static int iconv_statfs(const char *path, struct statvfs *stbuf)
{
    struct iconv *ic = iconv_get();
    char *newpath;
    int err = iconv_convpath(ic, path, &newpath, 0);
    if (!err) {
        err = fuse_fs_statfs(ic->next, newpath, stbuf);
        free(newpath);
    }
    return err;
}

static int iconv_flush(const char *path, struct fuse_file_info *fi)
{
    struct iconv *ic = iconv_get();
    char *newpath;
    int err = iconv_convpath(ic, path, &newpath, 0);
    if (!err) {
        err = fuse_fs_flush(ic->next, newpath, fi);
        free(newpath);
    }
    return err;
}

static int iconv_release(const char *path, struct fuse_file_info *fi)
{
    struct iconv *ic = iconv_get();
    char *newpath;
    int err = iconv_convpath(ic, path, &newpath, 0);
    if (!err) {
        err = fuse_fs_release(ic->next, newpath, fi);
        free(newpath);
    }
    return err;
}

static int iconv_fsync(const char *path, int isdatasync,
                       struct fuse_file_info *fi)
{
    struct iconv *ic = iconv_get();
    char *newpath;
    int err = iconv_convpath(ic, path, &newpath, 0);
    if (!err) {
        err = fuse_fs_fsync(ic->next, newpath, isdatasync, fi);
        free(newpath);
    }
    return err;
}

static int iconv_fsyncdir(const char *path, int isdatasync,
                          struct fuse_file_info *fi)
{
    struct iconv *ic = iconv_get();
    char *newpath;
    int err = iconv_convpath(ic, path, &newpath, 0);
    if (!err) {
        err = fuse_fs_fsyncdir(ic->next, newpath, isdatasync, fi);
        free(newpath);
    }
    return err;
}

static int iconv_setxattr(const char *path, const char *name,
                          const char *value, size_t size, int flags)
{
    struct iconv *ic = iconv_get();
    char *newpath;
    int err = iconv_convpath(ic, path, &newpath, 0);
    if (!err) {
        err = fuse_fs_setxattr(ic->next, newpath, name, value, size, flags);
        free(newpath);
    }
    return err;
}

static int iconv_getxattr(const char *path, const char *name, char *value,
                          size_t size)
{
    struct iconv *ic = iconv_get();
    char *newpath;
    int err = iconv_convpath(ic, path, &newpath, 0);
    if (!err) {
        err = fuse_fs_getxattr(ic->next, newpath, name, value, size);
        free(newpath);
    }
    return err;
}

static int iconv_listxattr(const char *path, char *list, size_t size)
{
    struct iconv *ic = iconv_get();
    char *newpath;
    int err = iconv_convpath(ic, path, &newpath, 0);
    if (!err) {
        err = fuse_fs_listxattr(ic->next, newpath, list, size);
        free(newpath);
    }
    return err;
}

static int iconv_removexattr(const char *path, const char *name)
{
    struct iconv *ic = iconv_get();
    char *newpath;
    int err = iconv_convpath(ic, path, &newpath, 0);
    if (!err) {
        err = fuse_fs_removexattr(ic->next, newpath, name);
        free(newpath);
    }
    return err;
}

static int iconv_lock(const char *path, struct fuse_file_info *fi, int cmd,
                      struct flock *lock)
{
    struct iconv *ic = iconv_get();
    char *newpath;
    int err = iconv_convpath(ic, path, &newpath, 0);
    if (!err) {
        err = fuse_fs_lock(ic->next, newpath, fi, cmd, lock);
        free(newpath);
    }
    return err;
}

static int iconv_bmap(const char *path, size_t blocksize, uint64_t *idx)
{
    struct iconv *ic = iconv_get();
    char *newpath;
    int err = iconv_convpath(ic, path, &newpath, 0);
    if (!err) {
        err = fuse_fs_bmap(ic->next, newpath, blocksize, idx);
        free(newpath);
    }
    return err;
}

static void *iconv_init(struct fuse_conn_info *conn)
{
    struct iconv *ic = iconv_get();
    fuse_fs_init(ic->next, conn);
    return ic;
}

static void iconv_destroy(void *data)
{
    struct iconv *ic = data;
    fuse_fs_destroy(ic->next);
    iconv_close(ic->tofs);
    iconv_close(ic->fromfs);
    pthread_mutex_destroy(&ic->lock);
    free(ic->from_code);
    free(ic->to_code);
    free(ic);
}

static struct fuse_operations iconv_oper = {
    .destroy	= iconv_destroy,
    .init	= iconv_init,
    .getattr	= iconv_getattr,
    .fgetattr	= iconv_fgetattr,
    .access	= iconv_access,
    .readlink	= iconv_readlink,
    .opendir	= iconv_opendir,
    .readdir	= iconv_readdir,
    .releasedir	= iconv_releasedir,
    .mknod	= iconv_mknod,
    .mkdir	= iconv_mkdir,
    .symlink	= iconv_symlink,
    .unlink	= iconv_unlink,
    .rmdir	= iconv_rmdir,
    .rename	= iconv_rename,
    .link	= iconv_link,
    .chmod	= iconv_chmod,
    .chown	= iconv_chown,
    .truncate	= iconv_truncate,
    .ftruncate	= iconv_ftruncate,
    .utimens	= iconv_utimens,
    .create	= iconv_create,
    .open	= iconv_open_file,
    .read	= iconv_read,
    .write	= iconv_write,
    .statfs	= iconv_statfs,
    .flush	= iconv_flush,
    .release	= iconv_release,
    .fsync	= iconv_fsync,
    .fsyncdir	= iconv_fsyncdir,
    .setxattr	= iconv_setxattr,
    .getxattr	= iconv_getxattr,
    .listxattr	= iconv_listxattr,
    .removexattr= iconv_removexattr,
    .lock	= iconv_lock,
    .bmap	= iconv_bmap,
};

static struct fuse_opt iconv_opts[] = {
    FUSE_OPT_KEY("-h", 0),
    FUSE_OPT_KEY("--help", 0),
    { "from_code=%s", offsetof(struct iconv, from_code), 0 },
    { "to_code=%s", offsetof(struct iconv, to_code), 1 },
    FUSE_OPT_END
};

static void iconv_help(void)
{
    char *old = strdup(setlocale(LC_CTYPE, ""));
    char *charmap = strdup(nl_langinfo(CODESET));
    setlocale(LC_CTYPE, old);
    free(old);
    fprintf(stderr,
"    -o from_code=CHARSET   original encoding of file names (default: UTF-8)\n"
"    -o to_code=CHARSET     new encoding of the file names (default: %s)\n",
            charmap);
    free(charmap);
}

static int iconv_opt_proc(void *data, const char *arg, int key,
                           struct fuse_args *outargs)
{
    (void) data; (void) arg; (void) outargs;

    if (!key) {
        iconv_help();
        return -1;
    }

    return 1;
}

static struct fuse_fs *iconv_new(struct fuse_args *args,
                                  struct fuse_fs *next[])
{
    struct fuse_fs *fs;
    struct iconv *ic;
    char *old = NULL;
    const char *from;
    const char *to;

    ic = calloc(1, sizeof(struct iconv));
    if (ic == NULL) {
        fprintf(stderr, "fuse-iconv: memory allocation failed\n");
        return NULL;
    }

    if (fuse_opt_parse(args, ic, iconv_opts, iconv_opt_proc) == -1)
        goto out_free;

    if (!next[0] || next[1]) {
        fprintf(stderr, "fuse-iconv: exactly one next filesystem required\n");
        goto out_free;
    }

    from = ic->from_code ? ic->from_code : "UTF-8";
    to = ic->to_code ? ic->to_code : "";
    /* FIXME: detect charset equivalence? */
    if (!to[0])
        old = strdup(setlocale(LC_CTYPE, ""));
    ic->tofs = iconv_open(from, to);
    if (ic->tofs == (iconv_t) -1) {
        fprintf(stderr, "fuse-iconv: cannot convert from %s to %s\n",
                to, from);
        goto out_free;
    }
    ic->fromfs = iconv_open(to, from);
    if (ic->tofs == (iconv_t) -1) {
        fprintf(stderr, "fuse-iconv: cannot convert from %s to %s\n",
                from, to);
        goto out_iconv_close_to;
    }
    if (old) {
        setlocale(LC_CTYPE, old);
        free(old);
    }

    ic->next = next[0];
    fs = fuse_fs_new(&iconv_oper, sizeof(iconv_oper), ic);
    if (!fs)
        goto out_iconv_close_from;

    return fs;

 out_iconv_close_from:
    iconv_close(ic->fromfs);
 out_iconv_close_to:
    iconv_close(ic->tofs);
 out_free:
    free(ic->from_code);
    free(ic->to_code);
    free(ic);
    return NULL;
}

FUSE_REGISTER_MODULE(iconv, iconv_new);