diff options
Diffstat (limited to 'contrib/syslinux-4.02/com32/lib/sys/zfile.c')
| -rw-r--r-- | contrib/syslinux-4.02/com32/lib/sys/zfile.c | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/contrib/syslinux-4.02/com32/lib/sys/zfile.c b/contrib/syslinux-4.02/com32/lib/sys/zfile.c new file mode 100644 index 0000000..0e6ba91 --- /dev/null +++ b/contrib/syslinux-4.02/com32/lib/sys/zfile.c @@ -0,0 +1,171 @@ +/* ----------------------------------------------------------------------- * + * + * Copyright 2003-2008 H. Peter Anvin - All Rights Reserved + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, + * copy, modify, merge, publish, distribute, sublicense, and/or + * sell copies of the Software, and to permit persons to whom + * the Software is furnished to do so, subject to the following + * conditions: + * + * The above copyright notice and this permission notice shall + * be included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES + * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT + * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR + * OTHER DEALINGS IN THE SOFTWARE. + * + * ----------------------------------------------------------------------- */ + +#include <errno.h> +#include <string.h> +#include <unistd.h> +#include <fcntl.h> +#include <stdlib.h> +#include <syslinux/zio.h> + +#include "file.h" +#include "zlib.h" + +/* + * zopen.c + * + * Open an ordinary file, possibly compressed; if so, insert + * an appropriate decompressor. + */ + +int __file_get_block(struct file_info *fp); +int __file_close(struct file_info *fp); + +static ssize_t gzip_file_read(struct file_info *, void *, size_t); +static int gzip_file_close(struct file_info *); + +static const struct input_dev gzip_file_dev = { + .dev_magic = __DEV_MAGIC, + .flags = __DEV_FILE | __DEV_INPUT, + .fileflags = O_RDONLY, + .read = gzip_file_read, + .close = gzip_file_close, + .open = NULL, +}; + +static int gzip_file_init(struct file_info *fp) +{ + z_streamp zs = calloc(1, sizeof(z_stream)); + + if (!zs) + return -1; + + fp->i.pvt = zs; + + zs->next_in = (void *)fp->i.datap; + zs->avail_in = fp->i.nbytes; + + if (inflateInit2(zs, 15 + 32) != Z_OK) { + errno = EIO; + return -1; + } + + fp->iop = &gzip_file_dev; + fp->i.fd.size = -1; /* Unknown */ + + return 0; +} + +static ssize_t gzip_file_read(struct file_info *fp, void *ptr, size_t n) +{ + z_streamp zs = fp->i.pvt; + int rv; + ssize_t bytes; + ssize_t nout = 0; + unsigned char *p = ptr; + + while (n) { + zs->next_out = p; + zs->avail_out = n; + + if (!zs->avail_in && fp->i.fd.handle) { + if (__file_get_block(fp)) + return nout ? nout : -1; + + zs->next_in = (void *)fp->i.datap; + zs->avail_in = fp->i.nbytes; + } + + rv = inflate(zs, Z_SYNC_FLUSH); + + bytes = n - zs->avail_out; + nout += bytes; + p += bytes; + n -= bytes; + + switch (rv) { + case Z_DATA_ERROR: + case Z_NEED_DICT: + case Z_BUF_ERROR: + case Z_STREAM_ERROR: + default: + errno = EIO; + return nout ? nout : -1; + case Z_MEM_ERROR: + errno = ENOMEM; + return nout ? nout : -1; + case Z_STREAM_END: + return nout; + case Z_OK: + break; + } + } + + return nout; +} + +static int gzip_file_close(struct file_info *fp) +{ + z_streamp zs = fp->i.pvt; + + inflateEnd(zs); + free(zs); + return __file_close(fp); +} + +int zopen(const char *pathname, int flags, ...) +{ + int fd, rv; + struct file_info *fp; + + /* We don't actually give a hoot about the creation bits... */ + fd = open(pathname, flags, 0); + + if (fd < 0) + return -1; + + fp = &__file_info[fd]; + + /* Need to get the first block into the buffer, but not consumed */ + if (__file_get_block(fp)) + goto err; + + if (fp->i.nbytes >= 14 && + (uint8_t) fp->i.buf[0] == 037 && + (uint8_t) fp->i.buf[1] == 0213 && /* gzip */ + fp->i.buf[2] == 8) /* deflate */ + rv = gzip_file_init(fp); + else + rv = 0; /* Plain file */ + + if (!rv) + return fd; + +err: + close(fd); + return -1; +} |