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-rw-r--r--archival/libunarchive/uncompress.c293
1 files changed, 0 insertions, 293 deletions
diff --git a/archival/libunarchive/uncompress.c b/archival/libunarchive/uncompress.c
deleted file mode 100644
index ddf293fd6..000000000
--- a/archival/libunarchive/uncompress.c
+++ /dev/null
@@ -1,293 +0,0 @@
-#include "config.h"
-#include "libbb.h"
-
-/* uncompress for busybox -- (c) 2002 Robert Griebl
- *
- * based on the original compress42.c source
- * (see disclaimer below)
- */
-
-
-/* (N)compress42.c - File compression ala IEEE Computer, Mar 1992.
- *
- * Authors:
- * Spencer W. Thomas (decvax!harpo!utah-cs!utah-gr!thomas)
- * Jim McKie (decvax!mcvax!jim)
- * Steve Davies (decvax!vax135!petsd!peora!srd)
- * Ken Turkowski (decvax!decwrl!turtlevax!ken)
- * James A. Woods (decvax!ihnp4!ames!jaw)
- * Joe Orost (decvax!vax135!petsd!joe)
- * Dave Mack (csu@alembic.acs.com)
- * Peter Jannesen, Network Communication Systems
- * (peter@ncs.nl)
- *
- * marc@suse.de : a small security fix for a buffer overflow
- *
- * [... History snipped ...]
- *
- */
-#include <stdio.h>
-#include <string.h>
-#include <unistd.h>
-
-/* Defailt input buffer size */
-#define IBUFSIZ 2048
-
-/* Default output buffer size */
-#define OBUFSIZ 2048
-
-/* Defines for third byte of header */
-#define MAGIC_1 (char_type)'\037' /* First byte of compressed file */
-#define MAGIC_2 (char_type)'\235' /* Second byte of compressed file */
-#define BIT_MASK 0x1f /* Mask for 'number of compresssion bits' */
- /* Masks 0x20 and 0x40 are free. */
- /* I think 0x20 should mean that there is */
- /* a fourth header byte (for expansion). */
-#define BLOCK_MODE 0x80 /* Block compresssion if table is full and */
- /* compression rate is dropping flush tables */
- /* the next two codes should not be changed lightly, as they must not */
- /* lie within the contiguous general code space. */
-#define FIRST 257 /* first free entry */
-#define CLEAR 256 /* table clear output code */
-
-#define INIT_BITS 9 /* initial number of bits/code */
-
-
-/* machine variants which require cc -Dmachine: pdp11, z8000, DOS */
-#define FAST
-
-#define HBITS 17 /* 50% occupancy */
-#define HSIZE (1<<HBITS)
-#define HMASK (HSIZE-1)
-#define HPRIME 9941
-#define BITS 16
-#undef MAXSEG_64K
-#define MAXCODE(n) (1L << (n))
-
-/* Block compress mode -C compatible with 2.0 */
-int block_mode = BLOCK_MODE;
-
-/* user settable max # bits/code */
-int maxbits = BITS;
-
-/* Exitcode of compress (-1 no file compressed) */
-int exit_code = -1;
-
-/* Input buffer */
-unsigned char inbuf[IBUFSIZ + 64];
-
-/* Output buffer */
-unsigned char outbuf[OBUFSIZ + 2048];
-
-
-long int htab[HSIZE];
-unsigned short codetab[HSIZE];
-
-#define htabof(i) htab[i]
-#define codetabof(i) codetab[i]
-#define tab_prefixof(i) codetabof(i)
-#define tab_suffixof(i) ((unsigned char *)(htab))[i]
-#define de_stack ((unsigned char *)&(htab[HSIZE-1]))
-#define clear_htab() memset(htab, -1, sizeof(htab))
-#define clear_tab_prefixof() memset(codetab, 0, 256);
-
-
-/*
- * Decompress stdin to stdout. This routine adapts to the codes in the
- * file building the "string" table on-the-fly; requiring no table to
- * be stored in the compressed file. The tables used herein are shared
- * with those of the compress() routine. See the definitions above.
- */
-
-extern int uncompress(int fd_in, int fd_out)
-{
- unsigned char *stackp;
- long int code;
- int finchar;
- long int oldcode;
- long int incode;
- int inbits;
- int posbits;
- int outpos;
- int insize;
- int bitmask;
- long int free_ent;
- long int maxcode;
- long int maxmaxcode;
- int n_bits;
- int rsize = 0;
-
- insize = 0;
-
- inbuf[0] = bb_xread_char(fd_in);
-
- maxbits = inbuf[0] & BIT_MASK;
- block_mode = inbuf[0] & BLOCK_MODE;
- maxmaxcode = MAXCODE(maxbits);
-
- if (maxbits > BITS) {
- bb_error_msg("compressed with %d bits, can only handle %d bits", maxbits,
- BITS);
- return -1;
- }
-
- maxcode = MAXCODE(n_bits = INIT_BITS) - 1;
- bitmask = (1 << n_bits) - 1;
- oldcode = -1;
- finchar = 0;
- outpos = 0;
- posbits = 0 << 3;
-
- free_ent = ((block_mode) ? FIRST : 256);
-
- /* As above, initialize the first 256 entries in the table. */
- clear_tab_prefixof();
-
- for (code = 255; code >= 0; --code) {
- tab_suffixof(code) = (unsigned char) code;
- }
-
- do {
- resetbuf:;
- {
- int i;
- int e;
- int o;
-
- e = insize - (o = (posbits >> 3));
-
- for (i = 0; i < e; ++i)
- inbuf[i] = inbuf[i + o];
-
- insize = e;
- posbits = 0;
- }
-
- if (insize < (int) sizeof(inbuf) - IBUFSIZ) {
- rsize = safe_read(fd_in, inbuf + insize, IBUFSIZ);
- insize += rsize;
- }
-
- inbits = ((rsize > 0) ? (insize - insize % n_bits) << 3 :
- (insize << 3) - (n_bits - 1));
-
- while (inbits > posbits) {
- if (free_ent > maxcode) {
- posbits =
- ((posbits - 1) +
- ((n_bits << 3) -
- (posbits - 1 + (n_bits << 3)) % (n_bits << 3)));
- ++n_bits;
- if (n_bits == maxbits) {
- maxcode = maxmaxcode;
- } else {
- maxcode = MAXCODE(n_bits) - 1;
- }
- bitmask = (1 << n_bits) - 1;
- goto resetbuf;
- }
- {
- unsigned char *p = &inbuf[posbits >> 3];
-
- code =
- ((((long) (p[0])) | ((long) (p[1]) << 8) |
- ((long) (p[2]) << 16)) >> (posbits & 0x7)) & bitmask;
- }
- posbits += n_bits;
-
-
- if (oldcode == -1) {
- outbuf[outpos++] = (unsigned char) (finchar =
- (int) (oldcode = code));
- continue;
- }
-
- if (code == CLEAR && block_mode) {
- clear_tab_prefixof();
- free_ent = FIRST - 1;
- posbits =
- ((posbits - 1) +
- ((n_bits << 3) -
- (posbits - 1 + (n_bits << 3)) % (n_bits << 3)));
- maxcode = MAXCODE(n_bits = INIT_BITS) - 1;
- bitmask = (1 << n_bits) - 1;
- goto resetbuf;
- }
-
- incode = code;
- stackp = de_stack;
-
- /* Special case for KwKwK string. */
- if (code >= free_ent) {
- if (code > free_ent) {
- unsigned char *p;
-
- posbits -= n_bits;
- p = &inbuf[posbits >> 3];
-
- bb_error_msg
- ("insize:%d posbits:%d inbuf:%02X %02X %02X %02X %02X (%d)",
- insize, posbits, p[-1], p[0], p[1], p[2], p[3],
- (posbits & 07));
- bb_error_msg("uncompress: corrupt input");
- return -1;
- }
-
- *--stackp = (unsigned char) finchar;
- code = oldcode;
- }
-
- /* Generate output characters in reverse order */
- while ((long int) code >= (long int) 256) {
- *--stackp = tab_suffixof(code);
- code = tab_prefixof(code);
- }
-
- *--stackp = (unsigned char) (finchar = tab_suffixof(code));
-
- /* And put them out in forward order */
- {
- int i;
-
- if (outpos + (i = (de_stack - stackp)) >= OBUFSIZ) {
- do {
- if (i > OBUFSIZ - outpos) {
- i = OBUFSIZ - outpos;
- }
-
- if (i > 0) {
- memcpy(outbuf + outpos, stackp, i);
- outpos += i;
- }
-
- if (outpos >= OBUFSIZ) {
- write(fd_out, outbuf, outpos);
- outpos = 0;
- }
- stackp += i;
- } while ((i = (de_stack - stackp)) > 0);
- } else {
- memcpy(outbuf + outpos, stackp, i);
- outpos += i;
- }
- }
-
- /* Generate the new entry. */
- if ((code = free_ent) < maxmaxcode) {
- tab_prefixof(code) = (unsigned short) oldcode;
- tab_suffixof(code) = (unsigned char) finchar;
- free_ent = code + 1;
- }
-
- /* Remember previous code. */
- oldcode = incode;
- }
-
- } while (rsize > 0);
-
- if (outpos > 0) {
- write(fd_out, outbuf, outpos);
- }
-
- return 0;
-}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-27 11:32:42 +0000