diff options
Diffstat (limited to 'archival')
| -rw-r--r-- | archival/gzip.c | 260 |
1 files changed, 50 insertions, 210 deletions
diff --git a/archival/gzip.c b/archival/gzip.c index c441942..a16e369 100644 --- a/archival/gzip.c +++ b/archival/gzip.c @@ -141,19 +141,19 @@ aa: 85.1% -- replaced with aa.gz /* Diagnostic functions */ #ifdef DEBUG -# define Assert(cond,msg) {if(!(cond)) bb_error_msg(msg);} -# define Trace(x) fprintf x -# define Tracev(x) {if (verbose) fprintf x ;} -# define Tracevv(x) {if (verbose>1) fprintf x ;} -# define Tracec(c,x) {if (verbose && (c)) fprintf x ;} -# define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;} +# define Assert(cond,msg) {if(!(cond)) bb_error_msg(msg);} +# define Trace(x) fprintf x +# define Tracev(x) {if (verbose) fprintf x ;} +# define Tracevv(x) {if (verbose>1) fprintf x ;} +# define Tracec(c,x) {if (verbose && (c)) fprintf x ;} +# define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;} #else -# define Assert(cond,msg) -# define Trace(x) -# define Tracev(x) -# define Tracevv(x) -# define Tracec(c,x) -# define Tracecv(c,x) +# define Assert(cond,msg) +# define Trace(x) +# define Tracev(x) +# define Tracevv(x) +# define Tracec(c,x) +# define Tracecv(c,x) #endif typedef unsigned char uch; @@ -163,7 +163,7 @@ typedef unsigned long ulg; /* from zip.c: */ static int zip(int in, int out); -static int file_read(char *buf, unsigned size); +static unsigned file_read(void *buf, unsigned size); /* from deflate.c */ static void lm_init(ush * flags); @@ -180,7 +180,6 @@ static void send_bits(int value, int length); static unsigned bi_reverse(unsigned value, int length); static void bi_windup(void); static void copy_block(char *buf, unsigned len, int header); -static int (*read_buf) (char *buf, unsigned size); static void flush_outbuf(void); @@ -298,22 +297,6 @@ static void clear_bufs(void) } /* =========================================================================== - * Does the same as write(), but also handles partial pipe writes and checks - * for error return. - */ -static void write_buf(int fd, void *buf, unsigned cnt) -{ - unsigned n; - - while ((n = write(fd, buf, cnt)) != cnt) { - if (n == (unsigned) (-1)) - bb_error_msg_and_die(bb_msg_write_error); - cnt -= n; - buf = (void *) ((char *) buf + n); - } -} - -/* =========================================================================== * Run a set of bytes through the crc shift register. If s is a NULL * pointer, then initialize the crc shift register contents instead. * Return the current crc in either case. @@ -333,62 +316,9 @@ static uint32_t updcrc(uch * s, unsigned n) } while (--n); } crc = c; - return ~c; + return c; } -/* bits.c -- output variable-length bit strings - * Copyright (C) 1992-1993 Jean-loup Gailly - * This is free software; you can redistribute it and/or modify it under the - * terms of the GNU General Public License, see the file COPYING. - */ - - -/* - * PURPOSE - * - * Output variable-length bit strings. Compression can be done - * to a file or to memory. (The latter is not supported in this version.) - * - * DISCUSSION - * - * The PKZIP "deflate" file format interprets compressed file data - * as a sequence of bits. Multi-bit strings in the file may cross - * byte boundaries without restriction. - * - * The first bit of each byte is the low-order bit. - * - * The routines in this file allow a variable-length bit value to - * be output right-to-left (useful for literal values). For - * left-to-right output (useful for code strings from the tree routines), - * the bits must have been reversed first with bi_reverse(). - * - * For in-memory compression, the compressed bit stream goes directly - * into the requested output buffer. The input data is read in blocks - * by the mem_read() function. The buffer is limited to 64K on 16 bit - * machines. - * - * INTERFACE - * - * void bi_init (FILE *zipfile) - * Initialize the bit string routines. - * - * void send_bits (int value, int length) - * Write out a bit string, taking the source bits right to - * left. - * - * int bi_reverse (int value, int length) - * Reverse the bits of a bit string, taking the source bits left to - * right and emitting them right to left. - * - * void bi_windup (void) - * Write out any remaining bits in an incomplete byte. - * - * void copy_block(char *buf, unsigned len, int header) - * Copy a stored block to the zip file, storing first the length and - * its one's complement if requested. - * - */ - /* =========================================================================== * Initialize the bit string routines. */ @@ -400,13 +330,6 @@ static void bi_init(int zipfile) #ifdef DEBUG bits_sent = 0L; #endif - - /* Set the defaults for file compression. They are set by memcompress - * for in-memory compression. - */ - if (zfile != NO_FILE) { - read_buf = file_read; - } } /* =========================================================================== @@ -418,7 +341,7 @@ static void send_bits(int value, int length) #ifdef DEBUG Tracev((stderr, " l %2d v %4x ", length, value)); Assert(length > 0 && length <= 15, "invalid length"); - bits_sent += (ulg) length; + bits_sent += length; #endif /* If not enough room in bi_buf, use (valid) bits from bi_buf and * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid)) @@ -477,8 +400,8 @@ static void copy_block(char *buf, unsigned len, int header) bi_windup(); /* align on byte boundary */ if (header) { - put_16bit((ush) len); - put_16bit((ush) ~ len); + put_16bit(len); + put_16bit(~len); #ifdef DEBUG bits_sent += 2 * 16; #endif @@ -491,61 +414,7 @@ static void copy_block(char *buf, unsigned len, int header) } } -/* deflate.c -- compress data using the deflation algorithm - * Copyright (C) 1992-1993 Jean-loup Gailly - * This is free software; you can redistribute it and/or modify it under the - * terms of the GNU General Public License, see the file COPYING. - */ - -/* - * PURPOSE - * - * Identify new text as repetitions of old text within a fixed- - * length sliding window trailing behind the new text. - * - * DISCUSSION - * - * The "deflation" process depends on being able to identify portions - * of the input text which are identical to earlier input (within a - * sliding window trailing behind the input currently being processed). - * - * The most straightforward technique turns out to be the fastest for - * most input files: try all possible matches and select the longest. - * The key feature of this algorithm is that insertions into the string - * dictionary are very simple and thus fast, and deletions are avoided - * completely. Insertions are performed at each input character, whereas - * string matches are performed only when the previous match ends. So it - * is preferable to spend more time in matches to allow very fast string - * insertions and avoid deletions. The matching algorithm for small - * strings is inspired from that of Rabin & Karp. A brute force approach - * is used to find longer strings when a small match has been found. - * A similar algorithm is used in comic (by Jan-Mark Wams) and freeze - * (by Leonid Broukhis). - * A previous version of this file used a more sophisticated algorithm - * (by Fiala and Greene) which is guaranteed to run in linear amortized - * time, but has a larger average cost, uses more memory and is patented. - * However the F&G algorithm may be faster for some highly redundant - * files if the parameter max_chain_length (described below) is too large. - * - * ACKNOWLEDGMENTS - * - * The idea of lazy evaluation of matches is due to Jan-Mark Wams, and - * I found it in 'freeze' written by Leonid Broukhis. - * Thanks to many info-zippers for bug reports and testing. - * - * REFERENCES - * - * APPNOTE.TXT documentation file in PKZIP 1.93a distribution. - * - * A description of the Rabin and Karp algorithm is given in the book - * "Algorithms" by R. Sedgewick, Addison-Wesley, p252. - * - * Fiala,E.R., and Greene,D.H. - * Data Compression with Finite Windows, Comm.ACM, 32,4 (1989) 490-595 - * - * INTERFACE - * - * void lm_init (int pack_level, ush *flags) +/* void lm_init (int pack_level, ush *flags) * Initialize the "longest match" routines for a new file * * ulg deflate (void) @@ -752,11 +621,12 @@ static void lm_init(ush * flags) strstart = 0; block_start = 0L; - lookahead = read_buf((char *) window, - sizeof(int) <= 2 ? (unsigned) WSIZE : 2 * WSIZE); + lookahead = file_read(window, + sizeof(int) <= 2 ? (unsigned) WSIZE : 2 * WSIZE); - if (lookahead == 0 || lookahead == (unsigned) EOF) { - eofile = 1, lookahead = 0; + if (lookahead == 0 || lookahead == (unsigned) -1) { + eofile = 1; + lookahead = 0; return; } eofile = 0; @@ -935,8 +805,8 @@ static void fill_window(void) } /* At this point, more >= 2 */ if (!eofile) { - n = read_buf((char *) window + strstart + lookahead, more); - if (n == 0 || n == (unsigned) EOF) { + n = file_read(window + strstart + lookahead, more); + if (n == 0 || n == (unsigned) -1) { eofile = 1; } else { lookahead += n; @@ -977,8 +847,9 @@ static ulg deflate(void) prev_length = match_length, prev_match = match_start; match_length = MIN_MATCH - 1; - if (hash_head != NIL && prev_length < max_lazy_match && - strstart - hash_head <= MAX_DIST) { + if (hash_head != 0 && prev_length < max_lazy_match + && strstart - hash_head <= MAX_DIST + ) { /* To simplify the code, we prevent matches with the string * of window index 0 (in particular we have to avoid a match * of the string with itself at the start of the input file). @@ -1024,7 +895,6 @@ static ulg deflate(void) strstart++; if (flush) FLUSH_BLOCK(0), block_start = strstart; - } else if (match_available) { /* If there was no match at the previous position, output a * single literal. If there was a match but the current match @@ -1060,30 +930,6 @@ static ulg deflate(void) return FLUSH_BLOCK(1); /* eof */ } -/* gzip (GNU zip) -- compress files with zip algorithm and 'compress' interface - * Copyright (C) 1992-1993 Jean-loup Gailly - * The unzip code was written and put in the public domain by Mark Adler. - * Portions of the lzw code are derived from the public domain 'compress' - * written by Spencer Thomas, Joe Orost, James Woods, Jim McKie, Steve Davies, - * Ken Turkowski, Dave Mack and Peter Jannesen. - * - * See the license_msg below and the file COPYING for the software license. - * See the file algorithm.doc for the compression algorithms and file formats. - */ - -/* Compress files with zip algorithm and 'compress' interface. - * See usage() and help() functions below for all options. - * Outputs: - * file.gz: compressed file with same mode, owner, and utimes - * or stdout with -c option or if stdin used as input. - * If the output file name had to be truncated, the original name is kept - * in the compressed file. - */ - -/* configuration */ - -typedef struct dirent dir_type; - /* ======================================================================== */ static void abort_gzip(int ATTRIBUTE_UNUSED ignored) { @@ -1268,12 +1114,12 @@ int gzip_main(int argc, char **argv) * * INTERFACE * - * void ct_init (ush *attr, int *methodp) + * void ct_init(ush *attr, int *methodp) * Allocate the match buffer, initialize the various tables and save * the location of the internal file attribute (ascii/binary) and * method (DEFLATE/STORE) * - * void ct_tally (int dist, int lc); + * void ct_tally(int dist, int lc); * Save the match info and tally the frequency counts. * * long flush_block (char *buf, ulg stored_len, int eof) @@ -1433,17 +1279,17 @@ typedef struct tree_desc { int max_code; /* largest code with non zero frequency */ } tree_desc; -static tree_desc l_desc = - { dyn_ltree, static_ltree, extra_lbits, LITERALS + 1, L_CODES, - MAX_BITS, 0 +static tree_desc l_desc = { + dyn_ltree, static_ltree, extra_lbits, + LITERALS + 1, L_CODES, MAX_BITS, 0 }; -static tree_desc d_desc = - { dyn_dtree, static_dtree, extra_dbits, 0, D_CODES, MAX_BITS, 0 }; +static tree_desc d_desc = { + dyn_dtree, static_dtree, extra_dbits, 0, D_CODES, MAX_BITS, 0 +}; -static tree_desc bl_desc = - { bl_tree, (ct_data *) 0, extra_blbits, 0, BL_CODES, MAX_BL_BITS, - 0 +static tree_desc bl_desc = { + bl_tree, NULL, extra_blbits, 0, BL_CODES, MAX_BL_BITS, 0 }; @@ -1451,8 +1297,9 @@ static ush bl_count[MAX_BITS + 1]; /* number of codes at each bit length for an optimal tree */ -static const uch bl_order[BL_CODES] -= { 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15 }; +static const uch bl_order[BL_CODES] = { + 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15 +}; /* The lengths of the bit length codes are sent in order of decreasing * probability, to avoid transmitting the lengths for unused bit length codes. @@ -2334,13 +2181,6 @@ static void set_file_type(void) } } -/* zip.c -- compress files to the gzip or pkzip format - * Copyright (C) 1992-1993 Jean-loup Gailly - * This is free software; you can redistribute it and/or modify it under the - * terms of the GNU General Public License, see the file COPYING. - */ - - static uint32_t crc; /* crc on uncompressed file data */ /* =========================================================================== @@ -2369,7 +2209,7 @@ static int zip(int in, int out) put_32bit(time_stamp); /* Write deflated file to zip file */ - crc = updcrc(0, 0); + crc = 0; bi_init(out); ct_init(&attr, &method); @@ -2388,25 +2228,24 @@ static int zip(int in, int out) return 0; } - /* =========================================================================== * Read a new buffer from the current input file, perform end-of-line * translation, and update the crc and input file size. * IN assertion: size >= 2 (for end-of-line translation) */ -static int file_read(char *buf, unsigned size) +static unsigned file_read(void *buf, unsigned size) { unsigned len; Assert(insize == 0, "inbuf not empty"); len = read(ifd, buf, size); - if (len == (unsigned) (-1) || len == 0) - return (int) len; + if (len == (unsigned)(-1) || len == 0) + return len; - crc = updcrc((uch *) buf, len); - isize += (ulg) len; - return (int) len; + crc = ~updcrc((uch *) buf, len); + isize += len; + return len; } /* =========================================================================== @@ -2418,6 +2257,7 @@ static void flush_outbuf(void) if (outcnt == 0) return; - write_buf(ofd, (char *) outbuf, outcnt); + xwrite(ofd, (char *) outbuf, outcnt); outcnt = 0; } + |