+++ /dev/null
-/*
- * Copyright 2007 David Gibson, IBM Corporation.
- * Based on earlier work, Copyright (C) Paul Mackerras 1997.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
- */
-
-#include <stddef.h>
-#include "string.h"
-#include "stdio.h"
-#include "ops.h"
-#include "gunzip_util.h"
-
-#define HEAD_CRC 2
-#define EXTRA_FIELD 4
-#define ORIG_NAME 8
-#define COMMENT 0x10
-#define RESERVED 0xe0
-
-/**
- * gunzip_start - prepare to decompress gzip data
- * @state: decompressor state structure to be initialized
- * @src: buffer containing gzip compressed or uncompressed data
- * @srclen: size in bytes of the buffer at src
- *
- * If the buffer at @src contains a gzip header, this function
- * initializes zlib to decompress the data, storing the decompression
- * state in @state. The other functions in this file can then be used
- * to decompress data from the gzipped stream.
- *
- * If the buffer at @src does not contain a gzip header, it is assumed
- * to contain uncompressed data. The buffer information is recorded
- * in @state and the other functions in this file will simply copy
- * data from the uncompressed data stream at @src.
- *
- * Any errors, such as bad compressed data, cause an error to be
- * printed an the platform's exit() function to be called.
- */
-void gunzip_start(struct gunzip_state *state, void *src, int srclen)
-{
- char *hdr = src;
- int hdrlen = 0;
-
- memset(state, 0, sizeof(*state));
-
- /* Check for gzip magic number */
- if ((hdr[0] == 0x1f) && (hdr[1] == 0x8b)) {
- /* gzip data, initialize zlib parameters */
- int r, flags;
-
- state->s.workspace = state->scratch;
- if (zlib_inflate_workspacesize() > sizeof(state->scratch))
- fatal("insufficient scratch space for gunzip\n\r");
-
- /* skip header */
- hdrlen = 10;
- flags = hdr[3];
- if (hdr[2] != Z_DEFLATED || (flags & RESERVED) != 0)
- fatal("bad gzipped data\n\r");
- if ((flags & EXTRA_FIELD) != 0)
- hdrlen = 12 + hdr[10] + (hdr[11] << 8);
- if ((flags & ORIG_NAME) != 0)
- while (hdr[hdrlen++] != 0)
- ;
- if ((flags & COMMENT) != 0)
- while (hdr[hdrlen++] != 0)
- ;
- if ((flags & HEAD_CRC) != 0)
- hdrlen += 2;
- if (hdrlen >= srclen)
- fatal("gunzip_start: ran out of data in header\n\r");
-
- r = zlib_inflateInit2(&state->s, -MAX_WBITS);
- if (r != Z_OK)
- fatal("inflateInit2 returned %d\n\r", r);
- }
-
- state->s.total_in = hdrlen;
- state->s.next_in = src + hdrlen;
- state->s.avail_in = srclen - hdrlen;
-}
-
-/**
- * gunzip_partial - extract bytes from a gzip data stream
- * @state: gzip state structure previously initialized by gunzip_start()
- * @dst: buffer to store extracted data
- * @dstlen: maximum number of bytes to extract
- *
- * This function extracts at most @dstlen bytes from the data stream
- * previously associated with @state by gunzip_start(), decompressing
- * if necessary. Exactly @dstlen bytes are extracted unless the data
- * stream doesn't contain enough bytes, in which case the entire
- * remainder of the stream is decompressed.
- *
- * Returns the actual number of bytes extracted. If any errors occur,
- * such as a corrupted compressed stream, an error is printed an the
- * platform's exit() function is called.
- */
-int gunzip_partial(struct gunzip_state *state, void *dst, int dstlen)
-{
- int len;
-
- if (state->s.workspace) {
- /* gunzipping */
- int r;
-
- state->s.next_out = dst;
- state->s.avail_out = dstlen;
- r = zlib_inflate(&state->s, Z_FULL_FLUSH);
- if (r != Z_OK && r != Z_STREAM_END)
- fatal("inflate returned %d msg: %s\n\r", r, state->s.msg);
- len = state->s.next_out - (Byte *)dst;
- } else {
- /* uncompressed image */
- len = min(state->s.avail_in, (uLong)dstlen);
- memcpy(dst, state->s.next_in, len);
- state->s.next_in += len;
- state->s.avail_in -= len;
- }
- return len;
-}
-
-/**
- * gunzip_exactly - extract a fixed number of bytes from a gzip data stream
- * @state: gzip state structure previously initialized by gunzip_start()
- * @dst: buffer to store extracted data
- * @dstlen: number of bytes to extract
- *
- * This function extracts exactly @dstlen bytes from the data stream
- * previously associated with @state by gunzip_start(), decompressing
- * if necessary.
- *
- * If there are less @dstlen bytes available in the data stream, or if
- * any other errors occur, such as a corrupted compressed stream, an
- * error is printed an the platform's exit() function is called.
- */
-void gunzip_exactly(struct gunzip_state *state, void *dst, int dstlen)
-{
- int len;
-
- len = gunzip_partial(state, dst, dstlen);
- if (len < dstlen)
- fatal("\n\rgunzip_exactly: ran out of data!"
- " Wanted %d, got %d.\n\r", dstlen, len);
-}
-
-/**
- * gunzip_discard - discard bytes from a gzip data stream
- * @state: gzip state structure previously initialized by gunzip_start()
- * @len: number of bytes to discard
- *
- * This function extracts, then discards exactly @len bytes from the
- * data stream previously associated with @state by gunzip_start().
- * Subsequent gunzip_partial(), gunzip_exactly() or gunzip_finish()
- * calls will extract the data following the discarded bytes in the
- * data stream.
- *
- * If there are less @len bytes available in the data stream, or if
- * any other errors occur, such as a corrupted compressed stream, an
- * error is printed an the platform's exit() function is called.
- */
-void gunzip_discard(struct gunzip_state *state, int len)
-{
- static char discard_buf[128];
-
- while (len > sizeof(discard_buf)) {
- gunzip_exactly(state, discard_buf, sizeof(discard_buf));
- len -= sizeof(discard_buf);
- }
-
- if (len > 0)
- gunzip_exactly(state, discard_buf, len);
-}
-
-/**
- * gunzip_finish - extract all remaining bytes from a gzip data stream
- * @state: gzip state structure previously initialized by gunzip_start()
- * @dst: buffer to store extracted data
- * @dstlen: maximum number of bytes to extract
- *
- * This function extracts all remaining data, or at most @dstlen
- * bytes, from the stream previously associated with @state by
- * gunzip_start(). zlib is then shut down, so it is an error to use
- * any of the functions in this file on @state until it is
- * re-initialized with another call to gunzip_start().
- *
- * If any errors occur, such as a corrupted compressed stream, an
- * error is printed an the platform's exit() function is called.
- */
-int gunzip_finish(struct gunzip_state *state, void *dst, int dstlen)
-{
- int len;
-
- len = gunzip_partial(state, dst, dstlen);
-
- if (state->s.workspace) {
- zlib_inflateEnd(&state->s);
- }
-
- return len;
-}
+++ /dev/null
-/*
- * Decompression convenience functions
- *
- * Copyright 2007 David Gibson, IBM Corporation.
- *
- * This file is licensed under the terms of the GNU General Public
- * License version 2. This program is licensed "as is" without any
- * warranty of any kind, whether express or implied.
- */
-#ifndef _PPC_BOOT_GUNZIP_UTIL_H_
-#define _PPC_BOOT_GUNZIP_UTIL_H_
-
-#include "zlib.h"
-
-/*
- * These functions are designed to make life easy for decompressing
- * kernel images, initrd images or any other gzip compressed image,
- * particularly if its useful to decompress part of the image (e.g. to
- * examine headers) before decompressing the remainder.
- *
- * To use:
- * - declare a gunzip_state structure
- * - use gunzip_start() to initialize the state, associating it
- * with a stream of compressed data
- * - use gunzip_partial(), gunzip_exactly() and gunzip_discard()
- * in any combination to extract pieces of data from the stream
- * - Finally use gunzip_finish() to extract the tail of the
- * compressed stream and wind up zlib
- */
-
-/* scratch space for gunzip; 46912 is from zlib_inflate_workspacesize() */
-#define GUNZIP_SCRATCH_SIZE 46912
-
-struct gunzip_state {
- z_stream s;
- char scratch[46912];
-};
-
-void gunzip_start(struct gunzip_state *state, void *src, int srclen);
-int gunzip_partial(struct gunzip_state *state, void *dst, int dstlen);
-void gunzip_exactly(struct gunzip_state *state, void *dst, int len);
-void gunzip_discard(struct gunzip_state *state, int len);
-int gunzip_finish(struct gunzip_state *state, void *dst, int len);
-
-#endif /* _PPC_BOOT_GUNZIP_UTIL_H_ */
projects / GitHub / LineageOS / android_kernel_motorola_exynos9610.git / commitdiff