338 lines
8.9 KiB
C
338 lines
8.9 KiB
C
/*
|
|
* Copyright (c) 1998 Michael Smith.
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include "stand.h"
|
|
|
|
#include <sys/stat.h>
|
|
#include <string.h>
|
|
#include <zlib.h>
|
|
|
|
#define Z_BUFSIZE 2048 /* XXX larger? */
|
|
|
|
struct z_file
|
|
{
|
|
int zf_rawfd;
|
|
off_t zf_dataoffset;
|
|
z_stream zf_zstream;
|
|
unsigned char zf_buf[Z_BUFSIZE];
|
|
int zf_endseen;
|
|
};
|
|
|
|
static int zf_fill(struct z_file *z);
|
|
static int zf_open(const char *path, struct open_file *f);
|
|
static int zf_close(struct open_file *f);
|
|
static int zf_read(struct open_file *f, void *buf, size_t size, size_t *resid);
|
|
static off_t zf_seek(struct open_file *f, off_t offset, int where);
|
|
static int zf_stat(struct open_file *f, struct stat *sb);
|
|
|
|
struct fs_ops gzipfs_fsops = {
|
|
"zip",
|
|
zf_open,
|
|
zf_close,
|
|
zf_read,
|
|
null_write,
|
|
zf_seek,
|
|
zf_stat,
|
|
null_readdir
|
|
};
|
|
|
|
static int
|
|
zf_fill(struct z_file *zf)
|
|
{
|
|
int result;
|
|
int req;
|
|
|
|
req = Z_BUFSIZE - zf->zf_zstream.avail_in;
|
|
result = 0;
|
|
|
|
/* If we need more */
|
|
if (req > 0) {
|
|
/* move old data to bottom of buffer */
|
|
if (req < Z_BUFSIZE)
|
|
bcopy(zf->zf_buf + req, zf->zf_buf, Z_BUFSIZE - req);
|
|
|
|
/* read to fill buffer and update availibility data */
|
|
result = read(zf->zf_rawfd, zf->zf_buf + zf->zf_zstream.avail_in, req);
|
|
zf->zf_zstream.next_in = zf->zf_buf;
|
|
if (result >= 0)
|
|
zf->zf_zstream.avail_in += result;
|
|
}
|
|
return(result);
|
|
}
|
|
|
|
/*
|
|
* Adapted from get_byte/check_header in libz
|
|
*
|
|
* Returns 0 if the header is OK, nonzero if not.
|
|
*/
|
|
static int
|
|
get_byte(struct z_file *zf, off_t *curoffp)
|
|
{
|
|
if ((zf->zf_zstream.avail_in == 0) && (zf_fill(zf) == -1))
|
|
return(-1);
|
|
zf->zf_zstream.avail_in--;
|
|
++*curoffp;
|
|
return(*(zf->zf_zstream.next_in)++);
|
|
}
|
|
|
|
static int gz_magic[2] = {0x1f, 0x8b}; /* gzip magic header */
|
|
|
|
/* gzip flag byte */
|
|
#define ASCII_FLAG 0x01 /* bit 0 set: file probably ascii text */
|
|
#define HEAD_CRC 0x02 /* bit 1 set: header CRC present */
|
|
#define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */
|
|
#define ORIG_NAME 0x08 /* bit 3 set: original file name present */
|
|
#define COMMENT 0x10 /* bit 4 set: file comment present */
|
|
#define RESERVED 0xE0 /* bits 5..7: reserved */
|
|
|
|
static int
|
|
check_header(struct z_file *zf)
|
|
{
|
|
int method; /* method byte */
|
|
int flags; /* flags byte */
|
|
uInt len;
|
|
int c;
|
|
|
|
zf->zf_dataoffset = 0;
|
|
/* Check the gzip magic header */
|
|
for (len = 0; len < 2; len++) {
|
|
c = get_byte(zf, &zf->zf_dataoffset);
|
|
if (c != gz_magic[len]) {
|
|
return(1);
|
|
}
|
|
}
|
|
method = get_byte(zf, &zf->zf_dataoffset);
|
|
flags = get_byte(zf, &zf->zf_dataoffset);
|
|
if (method != Z_DEFLATED || (flags & RESERVED) != 0) {
|
|
return(1);
|
|
}
|
|
|
|
/* Discard time, xflags and OS code: */
|
|
for (len = 0; len < 6; len++) (void)get_byte(zf, &zf->zf_dataoffset);
|
|
|
|
if ((flags & EXTRA_FIELD) != 0) { /* skip the extra field */
|
|
len = (uInt)get_byte(zf, &zf->zf_dataoffset);
|
|
len += ((uInt)get_byte(zf, &zf->zf_dataoffset))<<8;
|
|
/* len is garbage if EOF but the loop below will quit anyway */
|
|
while (len-- != 0 && get_byte(zf, &zf->zf_dataoffset) != -1) ;
|
|
}
|
|
if ((flags & ORIG_NAME) != 0) { /* skip the original file name */
|
|
while ((c = get_byte(zf, &zf->zf_dataoffset)) != 0 && c != -1) ;
|
|
}
|
|
if ((flags & COMMENT) != 0) { /* skip the .gz file comment */
|
|
while ((c = get_byte(zf, &zf->zf_dataoffset)) != 0 && c != -1) ;
|
|
}
|
|
if ((flags & HEAD_CRC) != 0) { /* skip the header crc */
|
|
for (len = 0; len < 2; len++) c = get_byte(zf, &zf->zf_dataoffset);
|
|
}
|
|
/* if there's data left, we're in business */
|
|
return((c == -1) ? 1 : 0);
|
|
}
|
|
|
|
static int
|
|
zf_open(const char *fname, struct open_file *f)
|
|
{
|
|
static char *zfname;
|
|
int rawfd;
|
|
struct z_file *zf;
|
|
char *cp;
|
|
int error;
|
|
struct stat sb;
|
|
|
|
/* Have to be in "just read it" mode */
|
|
if (f->f_flags != F_READ)
|
|
return(EPERM);
|
|
|
|
/* If the name already ends in .gz or .bz2, ignore it */
|
|
if ((cp = strrchr(fname, '.')) && (!strcmp(cp, ".gz")
|
|
|| !strcmp(cp, ".bz2") || !strcmp(cp, ".split")))
|
|
return(ENOENT);
|
|
|
|
/* Construct new name */
|
|
zfname = malloc(strlen(fname) + 4);
|
|
if (zfname == NULL)
|
|
return(ENOMEM);
|
|
sprintf(zfname, "%s.gz", fname);
|
|
|
|
/* Try to open the compressed datafile */
|
|
rawfd = open(zfname, O_RDONLY);
|
|
free(zfname);
|
|
if (rawfd == -1)
|
|
return(ENOENT);
|
|
|
|
if (fstat(rawfd, &sb) < 0) {
|
|
printf("zf_open: stat failed\n");
|
|
close(rawfd);
|
|
return(ENOENT);
|
|
}
|
|
if (!S_ISREG(sb.st_mode)) {
|
|
printf("zf_open: not a file\n");
|
|
close(rawfd);
|
|
return(EISDIR); /* best guess */
|
|
}
|
|
|
|
/* Allocate a z_file structure, populate it */
|
|
zf = malloc(sizeof(struct z_file));
|
|
if (zf == NULL)
|
|
return(ENOMEM);
|
|
bzero(zf, sizeof(struct z_file));
|
|
zf->zf_rawfd = rawfd;
|
|
|
|
/* Verify that the file is gzipped */
|
|
if (check_header(zf)) {
|
|
close(zf->zf_rawfd);
|
|
free(zf);
|
|
return(EFTYPE);
|
|
}
|
|
|
|
/* Initialise the inflation engine */
|
|
if ((error = inflateInit2(&(zf->zf_zstream), -15)) != Z_OK) {
|
|
printf("zf_open: inflateInit returned %d : %s\n", error, zf->zf_zstream.msg);
|
|
close(zf->zf_rawfd);
|
|
free(zf);
|
|
return(EIO);
|
|
}
|
|
|
|
/* Looks OK, we'll take it */
|
|
f->f_fsdata = zf;
|
|
return(0);
|
|
}
|
|
|
|
static int
|
|
zf_close(struct open_file *f)
|
|
{
|
|
struct z_file *zf = (struct z_file *)f->f_fsdata;
|
|
|
|
inflateEnd(&(zf->zf_zstream));
|
|
close(zf->zf_rawfd);
|
|
free(zf);
|
|
return(0);
|
|
}
|
|
|
|
static int
|
|
zf_read(struct open_file *f, void *buf, size_t size, size_t *resid)
|
|
{
|
|
struct z_file *zf = (struct z_file *)f->f_fsdata;
|
|
int error;
|
|
|
|
zf->zf_zstream.next_out = buf; /* where and how much */
|
|
zf->zf_zstream.avail_out = size;
|
|
|
|
while (zf->zf_zstream.avail_out && zf->zf_endseen == 0) {
|
|
if ((zf->zf_zstream.avail_in == 0) && (zf_fill(zf) == -1)) {
|
|
printf("zf_read: fill error\n");
|
|
return(EIO);
|
|
}
|
|
if (zf->zf_zstream.avail_in == 0) { /* oops, unexpected EOF */
|
|
printf("zf_read: unexpected EOF\n");
|
|
if (zf->zf_zstream.avail_out == size)
|
|
return(EIO);
|
|
break;
|
|
}
|
|
|
|
error = inflate(&zf->zf_zstream, Z_SYNC_FLUSH); /* decompression pass */
|
|
if (error == Z_STREAM_END) { /* EOF, all done */
|
|
zf->zf_endseen = 1;
|
|
break;
|
|
}
|
|
if (error != Z_OK) { /* argh, decompression error */
|
|
printf("inflate: %s\n", zf->zf_zstream.msg);
|
|
return(EIO);
|
|
}
|
|
}
|
|
if (resid != NULL)
|
|
*resid = zf->zf_zstream.avail_out;
|
|
return(0);
|
|
}
|
|
|
|
static int
|
|
zf_rewind(struct open_file *f)
|
|
{
|
|
struct z_file *zf = (struct z_file *)f->f_fsdata;
|
|
|
|
if (lseek(zf->zf_rawfd, zf->zf_dataoffset, SEEK_SET) == -1)
|
|
return(-1);
|
|
zf->zf_zstream.avail_in = 0;
|
|
zf->zf_zstream.next_in = NULL;
|
|
zf->zf_endseen = 0;
|
|
(void)inflateReset(&zf->zf_zstream);
|
|
|
|
return(0);
|
|
}
|
|
|
|
static off_t
|
|
zf_seek(struct open_file *f, off_t offset, int where)
|
|
{
|
|
struct z_file *zf = (struct z_file *)f->f_fsdata;
|
|
off_t target;
|
|
char discard[16];
|
|
|
|
switch (where) {
|
|
case SEEK_SET:
|
|
target = offset;
|
|
break;
|
|
case SEEK_CUR:
|
|
target = offset + zf->zf_zstream.total_out;
|
|
break;
|
|
default:
|
|
errno = EINVAL;
|
|
return(-1);
|
|
}
|
|
|
|
/* rewind if required */
|
|
if (target < zf->zf_zstream.total_out && zf_rewind(f) != 0)
|
|
return(-1);
|
|
|
|
/* skip forwards if required */
|
|
while (target > zf->zf_zstream.total_out) {
|
|
errno = zf_read(f, discard, min(sizeof(discard),
|
|
target - zf->zf_zstream.total_out), NULL);
|
|
if (errno)
|
|
return(-1);
|
|
}
|
|
/* This is where we are (be honest if we overshot) */
|
|
return(zf->zf_zstream.total_out);
|
|
}
|
|
|
|
|
|
static int
|
|
zf_stat(struct open_file *f, struct stat *sb)
|
|
{
|
|
struct z_file *zf = (struct z_file *)f->f_fsdata;
|
|
int result;
|
|
|
|
/* stat as normal, but indicate that size is unknown */
|
|
if ((result = fstat(zf->zf_rawfd, sb)) == 0)
|
|
sb->st_size = -1;
|
|
return(result);
|
|
}
|
|
|
|
|
|
|