diff options
Diffstat (limited to 'archival/libunarchive/decompress_uncompress.c')
-rw-r--r-- | archival/libunarchive/decompress_uncompress.c | 307 |
1 files changed, 0 insertions, 307 deletions
diff --git a/archival/libunarchive/decompress_uncompress.c b/archival/libunarchive/decompress_uncompress.c deleted file mode 100644 index 285b4efeb..000000000 --- a/archival/libunarchive/decompress_uncompress.c +++ /dev/null @@ -1,307 +0,0 @@ -/* vi: set sw=4 ts=4: */ -/* 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 "libbb.h" -#include "unarchive.h" - - -/* Default input buffer size */ -#define IBUFSIZ 2048 - -/* Default output buffer size */ -#define OBUFSIZ 2048 - -/* Defines for third byte of header */ -#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 compression 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 HBITS 17 /* 50% occupancy */ -#define HSIZE (1<<HBITS) -#define HMASK (HSIZE-1) /* unused */ -#define HPRIME 9941 /* unused */ -#define BITS 16 -#define BITS_STR "16" -#undef MAXSEG_64K /* unused */ -#define MAXCODE(n) (1L << (n)) - -#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_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. - */ - -IF_DESKTOP(long long) int FAST_FUNC -unpack_Z_stream(int fd_in, int fd_out) -{ - IF_DESKTOP(long long total_written = 0;) - IF_DESKTOP(long long) int retval = -1; - unsigned char *stackp; - long code; - int finchar; - long oldcode; - long incode; - int inbits; - int posbits; - int outpos; - int insize; - int bitmask; - long free_ent; - long maxcode; - long maxmaxcode; - int n_bits; - int rsize = 0; - unsigned char *inbuf; /* were eating insane amounts of stack - */ - unsigned char *outbuf; /* bad for some embedded targets */ - unsigned char *htab; - unsigned short *codetab; - - /* Hmm, these were statics - why?! */ - /* user settable max # bits/code */ - int maxbits; /* = BITS; */ - /* block compress mode -C compatible with 2.0 */ - int block_mode; /* = BLOCK_MODE; */ - - inbuf = xzalloc(IBUFSIZ + 64); - outbuf = xzalloc(OBUFSIZ + 2048); - htab = xzalloc(HSIZE); /* wsn't zeroed out before, maybe can xmalloc? */ - codetab = xzalloc(HSIZE * sizeof(codetab[0])); - - insize = 0; - - /* xread isn't good here, we have to return - caller may want - * to do some cleanup (e.g. delete incomplete unpacked file etc) */ - if (full_read(fd_in, inbuf, 1) != 1) { - bb_error_msg("short read"); - goto err; - } - - 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 " - BITS_STR" bits", maxbits); - goto err; - } - - n_bits = INIT_BITS; - maxcode = MAXCODE(INIT_BITS) - 1; - bitmask = (1 << INIT_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(); - done by xzalloc */ - - for (code = 255; code >= 0; --code) { - tab_suffixof(code) = (unsigned char) code; - } - - do { - resetbuf: - { - int i; - int e; - int o; - - o = posbits >> 3; - e = insize - o; - - for (i = 0; i < e; ++i) - inbuf[i] = inbuf[i + o]; - - insize = e; - posbits = 0; - } - - if (insize < (int) (IBUFSIZ + 64) - IBUFSIZ) { - rsize = safe_read(fd_in, inbuf + insize, IBUFSIZ); -//error check?? - 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) { - oldcode = code; - finchar = (int) oldcode; - outbuf[outpos++] = (unsigned char) finchar; - 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))); - n_bits = INIT_BITS; - maxcode = MAXCODE(INIT_BITS) - 1; - bitmask = (1 << INIT_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("corrupted data"); - goto err; - } - - *--stackp = (unsigned char) finchar; - code = oldcode; - } - - /* Generate output characters in reverse order */ - while ((long) code >= (long) 256) { - *--stackp = tab_suffixof(code); - code = tab_prefixof(code); - } - - finchar = tab_suffixof(code); - *--stackp = (unsigned char) finchar; - - /* And put them out in forward order */ - { - int i; - - i = de_stack - stackp; - if (outpos + i >= OBUFSIZ) { - do { - if (i > OBUFSIZ - outpos) { - i = OBUFSIZ - outpos; - } - - if (i > 0) { - memcpy(outbuf + outpos, stackp, i); - outpos += i; - } - - if (outpos >= OBUFSIZ) { - full_write(fd_out, outbuf, outpos); -//error check?? - IF_DESKTOP(total_written += outpos;) - outpos = 0; - } - stackp += i; - i = de_stack - stackp; - } while (i > 0); - } else { - memcpy(outbuf + outpos, stackp, i); - outpos += i; - } - } - - /* Generate the new entry. */ - code = free_ent; - if (code < 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) { - full_write(fd_out, outbuf, outpos); -//error check?? - IF_DESKTOP(total_written += outpos;) - } - - retval = IF_DESKTOP(total_written) + 0; - err: - free(inbuf); - free(outbuf); - free(htab); - free(codetab); - return retval; -} |