1 /* ----------------------------------------------------------------------- *
3 * Copyright 2003-2008 H. Peter Anvin - All Rights Reserved
5 * Permission is hereby granted, free of charge, to any person
6 * obtaining a copy of this software and associated documentation
7 * files (the "Software"), to deal in the Software without
8 * restriction, including without limitation the rights to use,
9 * copy, modify, merge, publish, distribute, sublicense, and/or
10 * sell copies of the Software, and to permit persons to whom
11 * the Software is furnished to do so, subject to the following
14 * The above copyright notice and this permission notice shall
15 * be included in all copies or substantial portions of the Software.
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
18 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
19 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
20 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
21 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
22 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
23 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
24 * OTHER DEALINGS IN THE SOFTWARE.
26 * ----------------------------------------------------------------------- */
33 #include <syslinux/zio.h>
41 * Open an ordinary file, possibly compressed; if so, insert
42 * an appropriate decompressor.
45 int __file_get_block(struct file_info *fp);
46 int __file_close(struct file_info *fp);
48 static ssize_t gzip_file_read(struct file_info *, void *, size_t);
49 static int gzip_file_close(struct file_info *);
51 static const struct input_dev gzip_file_dev = {
52 .dev_magic = __DEV_MAGIC,
53 .flags = __DEV_FILE | __DEV_INPUT,
54 .fileflags = O_RDONLY,
55 .read = gzip_file_read,
56 .close = gzip_file_close,
60 static int gzip_file_init(struct file_info *fp)
62 z_streamp zs = calloc(1, sizeof(z_stream));
69 zs->next_in = (void *)fp->i.datap;
70 zs->avail_in = fp->i.nbytes;
72 if (inflateInit2(zs, 15 + 32) != Z_OK) {
77 fp->iop = &gzip_file_dev;
78 fp->i.length = -1; /* Unknown */
83 static ssize_t gzip_file_read(struct file_info *fp, void *ptr, size_t n)
85 z_streamp zs = fp->i.pvt;
89 unsigned char *p = ptr;
95 if (!zs->avail_in && fp->i.filedes) {
96 if (__file_get_block(fp))
97 return nout ? nout : -1;
99 zs->next_in = (void *)fp->i.datap;
100 zs->avail_in = fp->i.nbytes;
103 rv = inflate(zs, Z_SYNC_FLUSH);
105 bytes = n - zs->avail_out;
117 return nout ? nout : -1;
120 return nout ? nout : -1;
131 static int gzip_file_close(struct file_info *fp)
133 z_streamp zs = fp->i.pvt;
137 return __file_close(fp);
140 int zopen(const char *pathname, int flags, ...)
143 struct file_info *fp;
145 /* We don't actually give a hoot about the creation bits... */
146 fd = open(pathname, flags, 0);
151 fp = &__file_info[fd];
153 /* Need to get the first block into the buffer, but not consumed */
154 if (__file_get_block(fp))
157 if (fp->i.nbytes >= 14 && (uint8_t) fp->i.buf[0] == 037 && (uint8_t) fp->i.buf[1] == 0213 && /* gzip */
158 fp->i.buf[2] == 8) /* deflate */
159 rv = gzip_file_init(fp);
161 rv = 0; /* Plain file */