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-rw-r--r--libbb/uncompress.c307
1 files changed, 0 insertions, 307 deletions
diff --git a/libbb/uncompress.c b/libbb/uncompress.c
deleted file mode 100644
index 949e27d..0000000
--- a/libbb/uncompress.c
+++ /dev/null
@@ -1,307 +0,0 @@
-#include "config.h"
-#include "libbb.h"
-
-#ifdef CONFIG_FEATURE_UNCOMPRESS
-
-/* 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>
-
-#define IBUFSIZ 2048 /* Defailt input buffer size */
-#define OBUFSIZ 2048 /* Default output buffer size */
-
- /* 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
-
-typedef long int code_int;
-
-typedef long int count_int;
-typedef long int cmp_code_int;
-
-typedef unsigned char char_type;
-
-#define MAXCODE(n) (1L << (n))
-
-
-
-int block_mode = BLOCK_MODE;/* Block compress mode -C compatible with 2.0*/
-int maxbits = BITS; /* user settable max # bits/code */
-int exit_code = -1; /* Exitcode of compress (-1 no file compressed) */
-
-char_type inbuf[IBUFSIZ+64]; /* Input buffer */
-char_type outbuf[OBUFSIZ+2048];/* Output buffer */
-
-
-count_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) ((char_type *)(htab))[i]
-#define de_stack ((char_type *)&(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)
-{
- char_type *stackp;
- code_int code;
- int finchar;
- code_int oldcode;
- code_int incode;
- int inbits;
- int posbits;
- int outpos;
- int insize;
- int bitmask;
- code_int free_ent;
- code_int maxcode;
- code_int maxmaxcode;
- int n_bits;
- int rsize = 0;
-
- insize = 0;
-
- inbuf [0] = xread_char(fd_in);
-
- maxbits = inbuf[0] & BIT_MASK;
- block_mode = inbuf[0] & BLOCK_MODE;
- maxmaxcode = MAXCODE(maxbits);
-
- if (maxbits > BITS)
- {
- fprintf(stderr, "compressed with %d bits, can only handle %d bits\n", maxbits, BITS);
- return -1;
- }
-
- //fprintf(stderr, "Bits: %d, block_mode: %d\n", maxbits, block_mode );
-
- 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);
-
- clear_tab_prefixof(); /* As above, initialize the first
- 256 entries in the table. */
-
- for (code = 255 ; code >= 0 ; --code)
- tab_suffixof(code) = (char_type)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)
- {
- xread_all(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;
- }
-
-
- {
- char_type *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++] = (char_type)(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;
-
- if (code >= free_ent) /* Special case for KwKwK string. */
- {
- if (code > free_ent)
- {
- char_type *p;
-
- posbits -= n_bits;
- p = &inbuf[posbits>>3];
-
- fprintf(stderr, "insize:%d posbits:%d inbuf:%02X %02X %02X %02X %02X (%d)\n", insize, posbits,
- p[-1],p[0],p[1],p[2],p[3], (posbits&07));
- fprintf(stderr, "uncompress: corrupt input\n");
- return -1;
- }
-
- *--stackp = (char_type)finchar;
- code = oldcode;
- }
-
- while ((cmp_code_int)code >= (cmp_code_int)256)
- { /* Generate output characters in reverse order */
- *--stackp = tab_suffixof(code);
- code = tab_prefixof(code);
- }
-
- *--stackp = (char_type)(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;
- }
- }
-
- if ((code = free_ent) < maxmaxcode) /* Generate the new entry. */
- {
- tab_prefixof(code) = (unsigned short)oldcode;
- tab_suffixof(code) = (char_type)finchar;
- free_ent = code+1;
- }
-
- oldcode = incode; /* Remember previous code. */
- }
-
- }
- while (rsize > 0);
-
- if (outpos > 0) {
- write(fd_out, outbuf, outpos);
- }
-
- return 0;
-}
-
-
-#endif
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