This is libstand; a support library for standalone executables (eg. bootstrap

modules).
Obtained from: NetBSD, with some architectural changes and many additions.

1 files changed, 316 insertions, 0 deletions

diff --git a/lib/libstand/gzipfs.c b/lib/libstand/gzipfs.c
new file mode 100644
index 0000000..9058907
--- /dev/null
+++ b/lib/libstand/gzipfs.c
@@ -0,0 +1,316 @@
+/* 
+ * 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.
+ *
+ *	$Id$
+ *
+ */
+
+#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;
+    z_stream		zf_zstream;
+    char		zf_buf[Z_BUFSIZE];
+};
+
+static int	zf_fill(struct z_file *z);
+static int	zf_open(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 zipfs_fsops = {
+    "zip",
+    zf_open, 
+    zf_close, 
+    zf_read,
+    null_write,
+    zf_seek,
+    zf_stat
+};
+
+void *
+calloc(int items, size_t size)
+{
+    return(malloc(items * size));
+}
+
+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)
+{
+    if ((zf->zf_zstream.avail_in == 0) && (zf_fill(zf) == -1))
+	return(-1);
+    zf->zf_zstream.avail_in--;
+    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;
+
+    /* Check the gzip magic header */
+    for (len = 0; len < 2; len++) {
+	c = get_byte(zf);
+	if (c != gz_magic[len]) {
+	    return(1);
+	}
+    }
+    method = get_byte(zf);
+    flags = get_byte(zf);
+    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);
+
+    if ((flags & EXTRA_FIELD) != 0) { /* skip the extra field */
+	len  =  (uInt)get_byte(zf);
+	len += ((uInt)get_byte(zf))<<8;
+	/* len is garbage if EOF but the loop below will quit anyway */
+	while (len-- != 0 && get_byte(zf) != -1) ;
+    }
+    if ((flags & ORIG_NAME) != 0) { /* skip the original file name */
+	while ((c = get_byte(zf)) != 0 && c != -1) ;
+    }
+    if ((flags & COMMENT) != 0) {   /* skip the .gz file comment */
+	while ((c = get_byte(zf)) != 0 && c != -1) ;
+    }
+    if ((flags & HEAD_CRC) != 0) {  /* skip the header crc */
+	for (len = 0; len < 2; len++) c = get_byte(zf);
+    }
+    /* if there's data left, we're in business */
+    return((c == -1) ? 1 : 0);
+}
+	
+static int
+zf_open(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, ignore it */
+    if ((cp = strrchr(fname, '.')) && !strcmp(cp, ".gz"))
+	return(ENOENT);
+
+    /* Construct new name */
+    zfname = malloc(strlen(fname) + 3);
+    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));
+    bzero(zf, sizeof(struct z_file));
+    zf->zf_rawfd = rawfd;
+
+    /* Verify that the file is gzipped (XXX why do this afterwards?) */
+    if (check_header(zf)) {
+	close(zf->zf_rawfd);
+	inflateEnd(&(zf->zf_zstream));
+	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) {
+	if ((zf->zf_zstream.avail_in == 0) && (zf_fill(zf) == -1)) {
+	    printf("zf_read: fill error\n");
+	    return(-1);
+	}
+	if (zf->zf_zstream.avail_in == 0) {		/* oops, unexpected EOF */
+	    printf("zf_read: unexpected EOF\n");
+	    break;
+	}
+
+	error = inflate(&zf->zf_zstream, Z_SYNC_FLUSH);	/* decompression pass */
+	if (error == Z_STREAM_END) {			/* EOF, all done */
+	    break;
+	}
+	if (error != Z_OK) {				/* argh, decompression error */
+	    printf("inflate: %s\n", zf->zf_zstream.msg);
+	    errno = EIO;
+	    return(-1);
+	}
+    }
+    if (resid != NULL)
+	*resid = zf->zf_zstream.avail_out;
+    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:
+	target = -1;
+    }
+
+    /* Can we get there from here? */
+    if (target < zf->zf_zstream.total_out) {
+	errno = EOFFSET;
+	return -1;
+    } 
+
+    /* skip forwards if required */
+    while (target > zf->zf_zstream.total_out) {
+	if (zf_read(f, discard, min(sizeof(discard), target - zf->zf_zstream.total_out), NULL) == -1)
+	    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);
+}
+
+
+