lib/libstand/splitfs.c

199767f8919635c4928607450d9e0abb932109ceToomas Soome/*
199767f8919635c4928607450d9e0abb932109ceToomas Soome * Copyright (c) 2002 Maxim Sobolev
199767f8919635c4928607450d9e0abb932109ceToomas Soome * All rights reserved.
199767f8919635c4928607450d9e0abb932109ceToomas Soome *
199767f8919635c4928607450d9e0abb932109ceToomas Soome * Redistribution and use in source and binary forms, with or without
199767f8919635c4928607450d9e0abb932109ceToomas Soome * modification, are permitted provided that the following conditions
199767f8919635c4928607450d9e0abb932109ceToomas Soome * are met:
199767f8919635c4928607450d9e0abb932109ceToomas Soome * 1. Redistributions of source code must retain the above copyright
199767f8919635c4928607450d9e0abb932109ceToomas Soome *    notice, this list of conditions and the following disclaimer.
199767f8919635c4928607450d9e0abb932109ceToomas Soome * 2. Redistributions in binary form must reproduce the above copyright
199767f8919635c4928607450d9e0abb932109ceToomas Soome *    notice, this list of conditions and the following disclaimer in the
199767f8919635c4928607450d9e0abb932109ceToomas Soome *    documentation and/or other materials provided with the distribution.
199767f8919635c4928607450d9e0abb932109ceToomas Soome *
199767f8919635c4928607450d9e0abb932109ceToomas Soome * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
199767f8919635c4928607450d9e0abb932109ceToomas Soome * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
199767f8919635c4928607450d9e0abb932109ceToomas Soome * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
199767f8919635c4928607450d9e0abb932109ceToomas Soome * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
199767f8919635c4928607450d9e0abb932109ceToomas Soome * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
199767f8919635c4928607450d9e0abb932109ceToomas Soome * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
199767f8919635c4928607450d9e0abb932109ceToomas Soome * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
199767f8919635c4928607450d9e0abb932109ceToomas Soome * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
199767f8919635c4928607450d9e0abb932109ceToomas Soome * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
199767f8919635c4928607450d9e0abb932109ceToomas Soome * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
199767f8919635c4928607450d9e0abb932109ceToomas Soome * SUCH DAMAGE.
199767f8919635c4928607450d9e0abb932109ceToomas Soome */
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome#include <sys/cdefs.h>
199767f8919635c4928607450d9e0abb932109ceToomas Soome__FBSDID("$FreeBSD$");
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome#include "stand.h"
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome#define NTRIES      (3)
199767f8919635c4928607450d9e0abb932109ceToomas Soome#define CONF_BUF    (512)
199767f8919635c4928607450d9e0abb932109ceToomas Soome#define SEEK_BUF    (512)
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soomestruct split_file
199767f8919635c4928607450d9e0abb932109ceToomas Soome{
199767f8919635c4928607450d9e0abb932109ceToomas Soome    char  **filesv; /* Filenames */
199767f8919635c4928607450d9e0abb932109ceToomas Soome    char  **descsv; /* Descriptions */
199767f8919635c4928607450d9e0abb932109ceToomas Soome    int   filesc;   /* Number of parts */
199767f8919635c4928607450d9e0abb932109ceToomas Soome    int   curfile;  /* Current file number */
199767f8919635c4928607450d9e0abb932109ceToomas Soome    int   curfd;    /* Current file descriptor */
199767f8919635c4928607450d9e0abb932109ceToomas Soome    off_t tot_pos;  /* Offset from the beginning of the sequence */
199767f8919635c4928607450d9e0abb932109ceToomas Soome    off_t file_pos; /* Offset from the beginning of the slice */
199767f8919635c4928607450d9e0abb932109ceToomas Soome};
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soomestatic int  split_openfile(struct split_file *sf);
199767f8919635c4928607450d9e0abb932109ceToomas Soomestatic int  splitfs_open(const char *path, struct open_file *f);
199767f8919635c4928607450d9e0abb932109ceToomas Soomestatic int  splitfs_close(struct open_file *f);
199767f8919635c4928607450d9e0abb932109ceToomas Soomestatic int  splitfs_read(struct open_file *f, void *buf, size_t size, size_t *resid);
199767f8919635c4928607450d9e0abb932109ceToomas Soomestatic off_t    splitfs_seek(struct open_file *f, off_t offset, int where);
199767f8919635c4928607450d9e0abb932109ceToomas Soomestatic int  splitfs_stat(struct open_file *f, struct stat *sb);
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soomestruct fs_ops splitfs_fsops = {
199767f8919635c4928607450d9e0abb932109ceToomas Soome    "split",
199767f8919635c4928607450d9e0abb932109ceToomas Soome    splitfs_open,
199767f8919635c4928607450d9e0abb932109ceToomas Soome    splitfs_close,
199767f8919635c4928607450d9e0abb932109ceToomas Soome    splitfs_read,
199767f8919635c4928607450d9e0abb932109ceToomas Soome    null_write,
199767f8919635c4928607450d9e0abb932109ceToomas Soome    splitfs_seek,
199767f8919635c4928607450d9e0abb932109ceToomas Soome    splitfs_stat,
199767f8919635c4928607450d9e0abb932109ceToomas Soome    null_readdir
199767f8919635c4928607450d9e0abb932109ceToomas Soome};
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soomestatic void
199767f8919635c4928607450d9e0abb932109ceToomas Soomesplit_file_destroy(struct split_file *sf)
199767f8919635c4928607450d9e0abb932109ceToomas Soome{
199767f8919635c4928607450d9e0abb932109ceToomas Soome    int i;
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome    if (sf->filesc > 0) {
199767f8919635c4928607450d9e0abb932109ceToomas Soome    for (i = 0; i < sf->filesc; i++) {
199767f8919635c4928607450d9e0abb932109ceToomas Soome        free(sf->filesv[i]);
199767f8919635c4928607450d9e0abb932109ceToomas Soome        free(sf->descsv[i]);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    }
199767f8919635c4928607450d9e0abb932109ceToomas Soome    free(sf->filesv);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    free(sf->descsv);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    }
199767f8919635c4928607450d9e0abb932109ceToomas Soome    free(sf);
199767f8919635c4928607450d9e0abb932109ceToomas Soome}
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soomestatic int
199767f8919635c4928607450d9e0abb932109ceToomas Soomesplit_openfile(struct split_file *sf)
199767f8919635c4928607450d9e0abb932109ceToomas Soome{
199767f8919635c4928607450d9e0abb932109ceToomas Soome    int i;
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome    for (i = 0;; i++) {
199767f8919635c4928607450d9e0abb932109ceToomas Soome    sf->curfd = open(sf->filesv[sf->curfile], O_RDONLY);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    if (sf->curfd >= 0)
199767f8919635c4928607450d9e0abb932109ceToomas Soome        break;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    if ((sf->curfd == -1) && (errno != ENOENT))
199767f8919635c4928607450d9e0abb932109ceToomas Soome        return (errno);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    if (i == NTRIES)
199767f8919635c4928607450d9e0abb932109ceToomas Soome        return (EIO);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    printf("\nInsert disk labelled %s and press any key...",
199767f8919635c4928607450d9e0abb932109ceToomas Soome        sf->descsv[sf->curfile]);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    getchar();
199767f8919635c4928607450d9e0abb932109ceToomas Soome    putchar('\n');
199767f8919635c4928607450d9e0abb932109ceToomas Soome    }
199767f8919635c4928607450d9e0abb932109ceToomas Soome    sf->file_pos = 0;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    return (0);
199767f8919635c4928607450d9e0abb932109ceToomas Soome}
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soomestatic int
199767f8919635c4928607450d9e0abb932109ceToomas Soomesplitfs_open(const char *fname, struct open_file *f)
199767f8919635c4928607450d9e0abb932109ceToomas Soome{
199767f8919635c4928607450d9e0abb932109ceToomas Soome    char *buf, *confname, *cp;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    int conffd;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    struct split_file *sf;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    struct stat sb;
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome    /* Have to be in "just read it" mode */
199767f8919635c4928607450d9e0abb932109ceToomas Soome    if (f->f_flags != F_READ)
199767f8919635c4928607450d9e0abb932109ceToomas Soome    return(EPERM);
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome    /* If the name already ends in `.split', ignore it */
199767f8919635c4928607450d9e0abb932109ceToomas Soome    if ((cp = strrchr(fname, '.')) && (!strcmp(cp, ".split")))
199767f8919635c4928607450d9e0abb932109ceToomas Soome    return(ENOENT);
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome    /* Construct new name */
199767f8919635c4928607450d9e0abb932109ceToomas Soome    confname = malloc(strlen(fname) + 7);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    sprintf(confname, "%s.split", fname);
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome    /* Try to open the configuration file */
199767f8919635c4928607450d9e0abb932109ceToomas Soome    conffd = open(confname, O_RDONLY);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    free(confname);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    if (conffd == -1)
199767f8919635c4928607450d9e0abb932109ceToomas Soome    return(ENOENT);
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome    if (fstat(conffd, &sb) < 0) {
199767f8919635c4928607450d9e0abb932109ceToomas Soome    printf("splitfs_open: stat failed\n");
199767f8919635c4928607450d9e0abb932109ceToomas Soome    close(conffd);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    return(ENOENT);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    }
199767f8919635c4928607450d9e0abb932109ceToomas Soome    if (!S_ISREG(sb.st_mode)) {
199767f8919635c4928607450d9e0abb932109ceToomas Soome    printf("splitfs_open: not a file\n");
199767f8919635c4928607450d9e0abb932109ceToomas Soome    close(conffd);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    return(EISDIR);         /* best guess */
199767f8919635c4928607450d9e0abb932109ceToomas Soome    }
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome    /* Allocate a split_file structure, populate it from the config file */
199767f8919635c4928607450d9e0abb932109ceToomas Soome    sf = malloc(sizeof(struct split_file));
199767f8919635c4928607450d9e0abb932109ceToomas Soome    bzero(sf, sizeof(struct split_file));
199767f8919635c4928607450d9e0abb932109ceToomas Soome    buf = malloc(CONF_BUF);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    while (fgetstr(buf, CONF_BUF, conffd) > 0) {
199767f8919635c4928607450d9e0abb932109ceToomas Soome    cp = buf;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    while ((*cp != '\0') && (isspace(*cp) == 0))
199767f8919635c4928607450d9e0abb932109ceToomas Soome        cp++;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    if (*cp != '\0') {
199767f8919635c4928607450d9e0abb932109ceToomas Soome        *cp = '\0';
199767f8919635c4928607450d9e0abb932109ceToomas Soome        cp++;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    }
199767f8919635c4928607450d9e0abb932109ceToomas Soome    while ((*cp != '\0') && (isspace(*cp) != 0))
199767f8919635c4928607450d9e0abb932109ceToomas Soome        cp++;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    if (*cp == '\0')
199767f8919635c4928607450d9e0abb932109ceToomas Soome        cp = buf;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    sf->filesc++;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    sf->filesv = realloc(sf->filesv, sizeof(*(sf->filesv)) * sf->filesc);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    sf->descsv = realloc(sf->descsv, sizeof(*(sf->descsv)) * sf->filesc);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    sf->filesv[sf->filesc - 1] = strdup(buf);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    sf->descsv[sf->filesc - 1] = strdup(cp);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    }
199767f8919635c4928607450d9e0abb932109ceToomas Soome    free(buf);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    close(conffd);
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome    if (sf->filesc == 0) {
199767f8919635c4928607450d9e0abb932109ceToomas Soome    split_file_destroy(sf);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    return(ENOENT);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    }
199767f8919635c4928607450d9e0abb932109ceToomas Soome    errno = split_openfile(sf);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    if (errno != 0) {
199767f8919635c4928607450d9e0abb932109ceToomas Soome    split_file_destroy(sf);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    return(ENOENT);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    }
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome    /* Looks OK, we'll take it */
199767f8919635c4928607450d9e0abb932109ceToomas Soome    f->f_fsdata = sf;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    return (0);
199767f8919635c4928607450d9e0abb932109ceToomas Soome}
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soomestatic int
199767f8919635c4928607450d9e0abb932109ceToomas Soomesplitfs_close(struct open_file *f)
199767f8919635c4928607450d9e0abb932109ceToomas Soome{
199767f8919635c4928607450d9e0abb932109ceToomas Soome    int fd;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    struct split_file *sf;
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome    sf = (struct split_file *)f->f_fsdata;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    fd = sf->curfd;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    split_file_destroy(sf);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    return(close(fd));
199767f8919635c4928607450d9e0abb932109ceToomas Soome}
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soomestatic int
199767f8919635c4928607450d9e0abb932109ceToomas Soomesplitfs_read(struct open_file *f, void *buf, size_t size, size_t *resid)
199767f8919635c4928607450d9e0abb932109ceToomas Soome{
199767f8919635c4928607450d9e0abb932109ceToomas Soome    ssize_t nread;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    size_t totread;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    struct split_file *sf;
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome    sf = (struct split_file *)f->f_fsdata;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    totread = 0;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    do {
199767f8919635c4928607450d9e0abb932109ceToomas Soome    nread = read(sf->curfd, buf, size - totread);
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome    /* Error? */
199767f8919635c4928607450d9e0abb932109ceToomas Soome    if (nread == -1)
199767f8919635c4928607450d9e0abb932109ceToomas Soome        return (errno);
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome    sf->tot_pos += nread;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    sf->file_pos += nread;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    totread += nread;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    buf = (char *)buf + nread;
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome    if (totread < size) {               /* EOF */
199767f8919635c4928607450d9e0abb932109ceToomas Soome        if (sf->curfile == (sf->filesc - 1))    /* Last slice */
199767f8919635c4928607450d9e0abb932109ceToomas Soome        break;
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome        /* Close previous slice */
199767f8919635c4928607450d9e0abb932109ceToomas Soome        if (close(sf->curfd) != 0)
199767f8919635c4928607450d9e0abb932109ceToomas Soome        return (errno);
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome        sf->curfile++;
199767f8919635c4928607450d9e0abb932109ceToomas Soome        errno = split_openfile(sf);
199767f8919635c4928607450d9e0abb932109ceToomas Soome        if (errno)
199767f8919635c4928607450d9e0abb932109ceToomas Soome            return (errno);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    }
199767f8919635c4928607450d9e0abb932109ceToomas Soome    } while (totread < size);
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome    if (resid != NULL)
199767f8919635c4928607450d9e0abb932109ceToomas Soome    *resid = size - totread;
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome    return (0);
199767f8919635c4928607450d9e0abb932109ceToomas Soome}
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soomestatic off_t
199767f8919635c4928607450d9e0abb932109ceToomas Soomesplitfs_seek(struct open_file *f, off_t offset, int where)
199767f8919635c4928607450d9e0abb932109ceToomas Soome{
199767f8919635c4928607450d9e0abb932109ceToomas Soome    int nread;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    size_t resid;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    off_t new_pos, seek_by;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    struct split_file *sf;
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome    sf = (struct split_file *)f->f_fsdata;
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome    seek_by = offset;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    switch (where) {
199767f8919635c4928607450d9e0abb932109ceToomas Soome    case SEEK_SET:
199767f8919635c4928607450d9e0abb932109ceToomas Soome    seek_by -= sf->tot_pos;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    break;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    case SEEK_CUR:
199767f8919635c4928607450d9e0abb932109ceToomas Soome    break;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    case SEEK_END:
199767f8919635c4928607450d9e0abb932109ceToomas Soome    panic("splitfs_seek: SEEK_END not supported");
199767f8919635c4928607450d9e0abb932109ceToomas Soome    break;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    default:
199767f8919635c4928607450d9e0abb932109ceToomas Soome    errno = EINVAL;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    return (-1);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    }
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome    if (seek_by > 0) {
199767f8919635c4928607450d9e0abb932109ceToomas Soome    /*
199767f8919635c4928607450d9e0abb932109ceToomas Soome     * Seek forward - implemented using splitfs_read(), because otherwise we'll be
199767f8919635c4928607450d9e0abb932109ceToomas Soome     * unable to detect that we have crossed slice boundary and hence
199767f8919635c4928607450d9e0abb932109ceToomas Soome     * unable to do a long seek crossing that boundary.
199767f8919635c4928607450d9e0abb932109ceToomas Soome     */
199767f8919635c4928607450d9e0abb932109ceToomas Soome    void *tmp;
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome    tmp = malloc(SEEK_BUF);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    if (tmp == NULL) {
199767f8919635c4928607450d9e0abb932109ceToomas Soome        errno = ENOMEM;
199767f8919635c4928607450d9e0abb932109ceToomas Soome        return (-1);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    }
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome    nread = 0;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    for (; seek_by > 0; seek_by -= nread) {
199767f8919635c4928607450d9e0abb932109ceToomas Soome        resid = 0;
199767f8919635c4928607450d9e0abb932109ceToomas Soome        errno = splitfs_read(f, tmp, min(seek_by, SEEK_BUF), &resid);
199767f8919635c4928607450d9e0abb932109ceToomas Soome        nread = min(seek_by, SEEK_BUF) - resid;
199767f8919635c4928607450d9e0abb932109ceToomas Soome        if ((errno != 0) || (nread == 0))
199767f8919635c4928607450d9e0abb932109ceToomas Soome        /* Error or EOF */
199767f8919635c4928607450d9e0abb932109ceToomas Soome        break;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    }
199767f8919635c4928607450d9e0abb932109ceToomas Soome    free(tmp);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    if (errno != 0)
199767f8919635c4928607450d9e0abb932109ceToomas Soome        return (-1);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    }
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome    if (seek_by != 0) {
199767f8919635c4928607450d9e0abb932109ceToomas Soome    /* Seek backward or seek past the boundary of the last slice */
199767f8919635c4928607450d9e0abb932109ceToomas Soome    if (sf->file_pos + seek_by < 0)
199767f8919635c4928607450d9e0abb932109ceToomas Soome        panic("splitfs_seek: can't seek past the beginning of the slice");
199767f8919635c4928607450d9e0abb932109ceToomas Soome    new_pos = lseek(sf->curfd, seek_by, SEEK_CUR);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    if (new_pos < 0) {
199767f8919635c4928607450d9e0abb932109ceToomas Soome        errno = EINVAL;
199767f8919635c4928607450d9e0abb932109ceToomas Soome        return (-1);
199767f8919635c4928607450d9e0abb932109ceToomas Soome    }
199767f8919635c4928607450d9e0abb932109ceToomas Soome    sf->tot_pos += new_pos - sf->file_pos;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    sf->file_pos = new_pos;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    }
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome    return (sf->tot_pos);
199767f8919635c4928607450d9e0abb932109ceToomas Soome}
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soomestatic int
199767f8919635c4928607450d9e0abb932109ceToomas Soomesplitfs_stat(struct open_file *f, struct stat *sb)
199767f8919635c4928607450d9e0abb932109ceToomas Soome{
199767f8919635c4928607450d9e0abb932109ceToomas Soome    int result;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    struct split_file *sf = (struct split_file *)f->f_fsdata;
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome    /* stat as normal, but indicate that size is unknown */
199767f8919635c4928607450d9e0abb932109ceToomas Soome    if ((result = fstat(sf->curfd, sb)) == 0)
199767f8919635c4928607450d9e0abb932109ceToomas Soome    sb->st_size = -1;
199767f8919635c4928607450d9e0abb932109ceToomas Soome    return (result);
199767f8919635c4928607450d9e0abb932109ceToomas Soome}