[1765] | 1 | /* vi: set sw=4 ts=4: */
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| 2 | /*
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| 3 | * Mini diff implementation for busybox, adapted from OpenBSD diff.
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| 4 | *
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[2725] | 5 | * Copyright (C) 2010 by Matheus Izvekov <mizvekov@gmail.com>
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[1765] | 6 | * Copyright (C) 2006 by Robert Sullivan <cogito.ergo.cogito@hotmail.com>
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| 7 | * Copyright (c) 2003 Todd C. Miller <Todd.Miller@courtesan.com>
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| 8 | *
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| 9 | * Sponsored in part by the Defense Advanced Research Projects
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| 10 | * Agency (DARPA) and Air Force Research Laboratory, Air Force
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| 11 | * Materiel Command, USAF, under agreement number F39502-99-1-0512.
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| 12 | *
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[2725] | 13 | * Licensed under GPLv2 or later, see file LICENSE in this source tree.
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[1765] | 14 | */
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| 15 |
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| 16 | /*
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[2725] | 17 | * The following code uses an algorithm due to Harold Stone,
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| 18 | * which finds a pair of longest identical subsequences in
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| 19 | * the two files.
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| 20 | *
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| 21 | * The major goal is to generate the match vector J.
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| 22 | * J[i] is the index of the line in file1 corresponding
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| 23 | * to line i in file0. J[i] = 0 if there is no
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| 24 | * such line in file1.
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| 25 | *
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| 26 | * Lines are hashed so as to work in core. All potential
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| 27 | * matches are located by sorting the lines of each file
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| 28 | * on the hash (called "value"). In particular, this
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| 29 | * collects the equivalence classes in file1 together.
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| 30 | * Subroutine equiv replaces the value of each line in
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| 31 | * file0 by the index of the first element of its
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| 32 | * matching equivalence in (the reordered) file1.
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| 33 | * To save space equiv squeezes file1 into a single
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| 34 | * array member in which the equivalence classes
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| 35 | * are simply concatenated, except that their first
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| 36 | * members are flagged by changing sign.
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| 37 | *
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| 38 | * Next the indices that point into member are unsorted into
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| 39 | * array class according to the original order of file0.
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| 40 | *
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| 41 | * The cleverness lies in routine stone. This marches
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| 42 | * through the lines of file0, developing a vector klist
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| 43 | * of "k-candidates". At step i a k-candidate is a matched
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| 44 | * pair of lines x,y (x in file0, y in file1) such that
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| 45 | * there is a common subsequence of length k
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| 46 | * between the first i lines of file0 and the first y
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| 47 | * lines of file1, but there is no such subsequence for
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| 48 | * any smaller y. x is the earliest possible mate to y
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| 49 | * that occurs in such a subsequence.
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| 50 | *
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| 51 | * Whenever any of the members of the equivalence class of
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| 52 | * lines in file1 matable to a line in file0 has serial number
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| 53 | * less than the y of some k-candidate, that k-candidate
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| 54 | * with the smallest such y is replaced. The new
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| 55 | * k-candidate is chained (via pred) to the current
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| 56 | * k-1 candidate so that the actual subsequence can
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| 57 | * be recovered. When a member has serial number greater
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| 58 | * that the y of all k-candidates, the klist is extended.
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| 59 | * At the end, the longest subsequence is pulled out
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| 60 | * and placed in the array J by unravel
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| 61 | *
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| 62 | * With J in hand, the matches there recorded are
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| 63 | * checked against reality to assure that no spurious
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| 64 | * matches have crept in due to hashing. If they have,
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| 65 | * they are broken, and "jackpot" is recorded--a harmless
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| 66 | * matter except that a true match for a spuriously
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| 67 | * mated line may now be unnecessarily reported as a change.
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| 68 | *
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| 69 | * Much of the complexity of the program comes simply
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| 70 | * from trying to minimize core utilization and
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| 71 | * maximize the range of doable problems by dynamically
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| 72 | * allocating what is needed and reusing what is not.
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| 73 | * The core requirements for problems larger than somewhat
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| 74 | * are (in words) 2*length(file0) + length(file1) +
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| 75 | * 3*(number of k-candidates installed), typically about
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| 76 | * 6n words for files of length n.
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[1765] | 77 | */
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| 78 |
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[3232] | 79 | //usage:#define diff_trivial_usage
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| 80 | //usage: "[-abBdiNqrTstw] [-L LABEL] [-S FILE] [-U LINES] FILE1 FILE2"
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| 81 | //usage:#define diff_full_usage "\n\n"
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| 82 | //usage: "Compare files line by line and output the differences between them.\n"
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| 83 | //usage: "This implementation supports unified diffs only.\n"
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| 84 | //usage: "\n -a Treat all files as text"
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| 85 | //usage: "\n -b Ignore changes in the amount of whitespace"
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| 86 | //usage: "\n -B Ignore changes whose lines are all blank"
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| 87 | //usage: "\n -d Try hard to find a smaller set of changes"
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| 88 | //usage: "\n -i Ignore case differences"
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| 89 | //usage: "\n -L Use LABEL instead of the filename in the unified header"
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| 90 | //usage: "\n -N Treat absent files as empty"
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| 91 | //usage: "\n -q Output only whether files differ"
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| 92 | //usage: "\n -r Recurse"
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| 93 | //usage: "\n -S Start with FILE when comparing directories"
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| 94 | //usage: "\n -T Make tabs line up by prefixing a tab when necessary"
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| 95 | //usage: "\n -s Report when two files are the same"
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| 96 | //usage: "\n -t Expand tabs to spaces in output"
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| 97 | //usage: "\n -U Output LINES lines of context"
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| 98 | //usage: "\n -w Ignore all whitespace"
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| 99 |
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[2725] | 100 | #include "libbb.h"
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[1765] | 101 |
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[2725] | 102 | #if 0
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[3232] | 103 | # define dbg_error_msg(...) bb_error_msg(__VA_ARGS__)
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[2725] | 104 | #else
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[3232] | 105 | # define dbg_error_msg(...) ((void)0)
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[2725] | 106 | #endif
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[1765] | 107 |
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[2725] | 108 | enum { /* print_status() and diffreg() return values */
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| 109 | STATUS_SAME, /* files are the same */
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| 110 | STATUS_DIFFER, /* files differ */
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| 111 | STATUS_BINARY, /* binary files differ */
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[1765] | 112 | };
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| 113 |
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[2725] | 114 | enum { /* Commandline flags */
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| 115 | FLAG_a,
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| 116 | FLAG_b,
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| 117 | FLAG_d,
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| 118 | FLAG_i,
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| 119 | FLAG_L, /* never used, handled by getopt32 */
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| 120 | FLAG_N,
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| 121 | FLAG_q,
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| 122 | FLAG_r,
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| 123 | FLAG_s,
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| 124 | FLAG_S, /* never used, handled by getopt32 */
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| 125 | FLAG_t,
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| 126 | FLAG_T,
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| 127 | FLAG_U, /* never used, handled by getopt32 */
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| 128 | FLAG_w,
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| 129 | FLAG_u, /* ignored, this is the default */
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| 130 | FLAG_p, /* not implemented */
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| 131 | FLAG_B,
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| 132 | FLAG_E, /* not implemented */
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[1765] | 133 | };
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[2725] | 134 | #define FLAG(x) (1 << FLAG_##x)
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[1765] | 135 |
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[2725] | 136 | /* We cache file position to avoid excessive seeking */
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| 137 | typedef struct FILE_and_pos_t {
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| 138 | FILE *ft_fp;
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| 139 | off_t ft_pos;
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| 140 | } FILE_and_pos_t;
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[1765] | 141 |
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| 142 | struct globals {
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[2725] | 143 | smallint exit_status;
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| 144 | int opt_U_context;
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| 145 | const char *other_dir;
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| 146 | char *label[2];
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| 147 | struct stat stb[2];
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[1765] | 148 | };
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| 149 | #define G (*ptr_to_globals)
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[2725] | 150 | #define exit_status (G.exit_status )
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| 151 | #define opt_U_context (G.opt_U_context )
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| 152 | #define label (G.label )
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| 153 | #define stb (G.stb )
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[1765] | 154 | #define INIT_G() do { \
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[2725] | 155 | SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
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| 156 | opt_U_context = 3; \
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[1765] | 157 | } while (0)
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| 158 |
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[2725] | 159 | typedef int token_t;
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[1765] | 160 |
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[2725] | 161 | enum {
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| 162 | /* Public */
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| 163 | TOK_EMPTY = 1 << 9, /* Line fully processed, you can proceed to the next */
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| 164 | TOK_EOF = 1 << 10, /* File ended */
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| 165 | /* Private (Only to be used by read_token() */
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| 166 | TOK_EOL = 1 << 11, /* we saw EOL (sticky) */
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| 167 | TOK_SPACE = 1 << 12, /* used -b code, means we are skipping spaces */
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| 168 | SHIFT_EOF = (sizeof(token_t)*8 - 8) - 1,
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| 169 | CHAR_MASK = 0x1ff, /* 8th bit is used to distinguish EOF from 0xff */
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| 170 | };
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[1765] | 171 |
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[2725] | 172 | /* Restores full EOF from one 8th bit: */
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| 173 | //#define TOK2CHAR(t) (((t) << SHIFT_EOF) >> SHIFT_EOF)
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| 174 | /* We don't really need the above, we only need to have EOF != any_real_char: */
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| 175 | #define TOK2CHAR(t) ((t) & CHAR_MASK)
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| 176 |
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| 177 | static void seek_ft(FILE_and_pos_t *ft, off_t pos)
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[1765] | 178 | {
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[2725] | 179 | if (ft->ft_pos != pos) {
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| 180 | ft->ft_pos = pos;
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| 181 | fseeko(ft->ft_fp, pos, SEEK_SET);
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[1765] | 182 | }
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| 183 | }
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[2725] | 184 |
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| 185 | /* Reads tokens from given fp, handling -b and -w flags
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| 186 | * The user must reset tok every line start
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[1765] | 187 | */
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[2725] | 188 | static int read_token(FILE_and_pos_t *ft, token_t tok)
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[1765] | 189 | {
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[2725] | 190 | tok |= TOK_EMPTY;
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| 191 | while (!(tok & TOK_EOL)) {
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| 192 | bool is_space;
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| 193 | int t;
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[1765] | 194 |
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[2725] | 195 | t = fgetc(ft->ft_fp);
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| 196 | if (t != EOF)
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| 197 | ft->ft_pos++;
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| 198 | is_space = (t == EOF || isspace(t));
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| 199 |
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| 200 | /* If t == EOF (-1), set both TOK_EOF and TOK_EOL */
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| 201 | tok |= (t & (TOK_EOF + TOK_EOL));
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| 202 | /* Only EOL? */
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| 203 | if (t == '\n')
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| 204 | tok |= TOK_EOL;
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| 205 |
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| 206 | if (option_mask32 & FLAG(i)) /* Handcoded tolower() */
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| 207 | t = (t >= 'A' && t <= 'Z') ? t - ('A' - 'a') : t;
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| 208 |
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| 209 | if ((option_mask32 & FLAG(w)) && is_space)
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| 210 | continue;
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| 211 |
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| 212 | /* Trim char value to low 9 bits */
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| 213 | t &= CHAR_MASK;
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| 214 |
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| 215 | if (option_mask32 & FLAG(b)) {
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| 216 | /* Was prev char whitespace? */
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| 217 | if (tok & TOK_SPACE) { /* yes */
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| 218 | if (is_space) /* this one too, ignore it */
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| 219 | continue;
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| 220 | tok &= ~TOK_SPACE;
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| 221 | } else if (is_space) {
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| 222 | /* 1st whitespace char.
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| 223 | * Set TOK_SPACE and replace char by ' ' */
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| 224 | t = TOK_SPACE + ' ';
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[1765] | 225 | }
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| 226 | }
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[2725] | 227 | /* Clear EMPTY */
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| 228 | tok &= ~(TOK_EMPTY + CHAR_MASK);
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| 229 | /* Assign char value (low 9 bits) and maybe set TOK_SPACE */
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| 230 | tok |= t;
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| 231 | break;
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[1765] | 232 | }
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[2725] | 233 | #if 0
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| 234 | bb_error_msg("fp:%p tok:%x '%c'%s%s%s%s", fp, tok, tok & 0xff
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| 235 | , tok & TOK_EOF ? " EOF" : ""
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| 236 | , tok & TOK_EOL ? " EOL" : ""
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| 237 | , tok & TOK_EMPTY ? " EMPTY" : ""
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| 238 | , tok & TOK_SPACE ? " SPACE" : ""
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| 239 | );
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| 240 | #endif
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| 241 | return tok;
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[1765] | 242 | }
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| 243 |
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[2725] | 244 | struct cand {
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| 245 | int x;
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| 246 | int y;
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| 247 | int pred;
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| 248 | };
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[1765] | 249 |
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[2725] | 250 | static int search(const int *c, int k, int y, const struct cand *list)
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[1765] | 251 | {
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[2725] | 252 | int i, j;
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[1765] | 253 |
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[2725] | 254 | if (list[c[k]].y < y) /* quick look for typical case */
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| 255 | return k + 1;
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| 256 |
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| 257 | for (i = 0, j = k + 1;;) {
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| 258 | const int l = (i + j) >> 1;
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| 259 | if (l > i) {
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| 260 | const int t = list[c[l]].y;
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| 261 | if (t > y)
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| 262 | j = l;
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| 263 | else if (t < y)
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| 264 | i = l;
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| 265 | else
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| 266 | return l;
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| 267 | } else
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| 268 | return l + 1;
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[1765] | 269 | }
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| 270 | }
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| 271 |
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[2725] | 272 | static unsigned isqrt(unsigned n)
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[1765] | 273 | {
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[2725] | 274 | unsigned x = 1;
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| 275 | while (1) {
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| 276 | const unsigned y = x;
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| 277 | x = ((n / x) + x) >> 1;
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| 278 | if (x <= (y + 1) && x >= (y - 1))
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| 279 | return x;
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[1765] | 280 | }
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| 281 | }
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| 282 |
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[2725] | 283 | static void stone(const int *a, int n, const int *b, int *J, int pref)
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[1765] | 284 | {
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[2725] | 285 | const unsigned isq = isqrt(n);
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| 286 | const unsigned bound =
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| 287 | (option_mask32 & FLAG(d)) ? UINT_MAX : MAX(256, isq);
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| 288 | int clen = 1;
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| 289 | int clistlen = 100;
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| 290 | int k = 0;
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| 291 | struct cand *clist = xzalloc(clistlen * sizeof(clist[0]));
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| 292 | struct cand cand;
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| 293 | struct cand *q;
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| 294 | int *klist = xzalloc((n + 2) * sizeof(klist[0]));
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| 295 | /*clist[0] = (struct cand){0}; - xzalloc did it */
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| 296 | /*klist[0] = 0; */
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[1765] | 297 |
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[2725] | 298 | for (cand.x = 1; cand.x <= n; cand.x++) {
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| 299 | int j = a[cand.x], oldl = 0;
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| 300 | unsigned numtries = 0;
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| 301 | if (j == 0)
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| 302 | continue;
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| 303 | cand.y = -b[j];
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| 304 | cand.pred = klist[0];
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| 305 | do {
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| 306 | int l, tc;
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| 307 | if (cand.y <= clist[cand.pred].y)
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| 308 | continue;
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| 309 | l = search(klist, k, cand.y, clist);
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| 310 | if (l != oldl + 1)
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| 311 | cand.pred = klist[l - 1];
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| 312 | if (l <= k && clist[klist[l]].y <= cand.y)
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| 313 | continue;
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| 314 | if (clen == clistlen) {
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| 315 | clistlen = clistlen * 11 / 10;
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| 316 | clist = xrealloc(clist, clistlen * sizeof(clist[0]));
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| 317 | }
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| 318 | clist[clen] = cand;
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| 319 | tc = klist[l];
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| 320 | klist[l] = clen++;
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| 321 | if (l <= k) {
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| 322 | cand.pred = tc;
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| 323 | oldl = l;
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| 324 | numtries++;
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| 325 | } else {
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| 326 | k++;
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| 327 | break;
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| 328 | }
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| 329 | } while ((cand.y = b[++j]) > 0 && numtries < bound);
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[1765] | 330 | }
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[2725] | 331 | /* Unravel */
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| 332 | for (q = clist + klist[k]; q->y; q = clist + q->pred)
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| 333 | J[q->x + pref] = q->y + pref;
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| 334 | free(klist);
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| 335 | free(clist);
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[1765] | 336 | }
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| 337 |
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[2725] | 338 | struct line {
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| 339 | /* 'serial' is not used in the begining, so we reuse it
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| 340 | * to store line offsets, thus reducing memory pressure
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| 341 | */
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| 342 | union {
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| 343 | unsigned serial;
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| 344 | off_t offset;
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| 345 | };
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| 346 | unsigned value;
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| 347 | };
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[1765] | 348 |
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| 349 | static void equiv(struct line *a, int n, struct line *b, int m, int *c)
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| 350 | {
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[2725] | 351 | int i = 1, j = 1;
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[1765] | 352 |
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| 353 | while (i <= n && j <= m) {
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| 354 | if (a[i].value < b[j].value)
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| 355 | a[i++].value = 0;
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| 356 | else if (a[i].value == b[j].value)
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| 357 | a[i++].value = j;
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| 358 | else
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| 359 | j++;
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| 360 | }
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| 361 | while (i <= n)
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| 362 | a[i++].value = 0;
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| 363 | b[m + 1].value = 0;
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| 364 | j = 0;
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| 365 | while (++j <= m) {
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| 366 | c[j] = -b[j].serial;
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| 367 | while (b[j + 1].value == b[j].value) {
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| 368 | j++;
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| 369 | c[j] = b[j].serial;
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| 370 | }
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| 371 | }
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| 372 | c[j] = -1;
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| 373 | }
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| 374 |
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[2725] | 375 | static void unsort(const struct line *f, int l, int *b)
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[1765] | 376 | {
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| 377 | int i;
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[2725] | 378 | int *a = xmalloc((l + 1) * sizeof(a[0]));
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[1765] | 379 | for (i = 1; i <= l; i++)
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| 380 | a[f[i].serial] = f[i].value;
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| 381 | for (i = 1; i <= l; i++)
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| 382 | b[i] = a[i];
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| 383 | free(a);
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| 384 | }
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| 385 |
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[2725] | 386 | static int line_compar(const void *a, const void *b)
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[1765] | 387 | {
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[2725] | 388 | #define l0 ((const struct line*)a)
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| 389 | #define l1 ((const struct line*)b)
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| 390 | int r = l0->value - l1->value;
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| 391 | if (r)
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| 392 | return r;
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| 393 | return l0->serial - l1->serial;
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| 394 | #undef l0
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| 395 | #undef l1
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[1765] | 396 | }
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| 397 |
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[2725] | 398 | static void fetch(FILE_and_pos_t *ft, const off_t *ix, int a, int b, int ch)
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[1765] | 399 | {
|
---|
[2725] | 400 | int i, j, col;
|
---|
[1765] | 401 | for (i = a; i <= b; i++) {
|
---|
[2725] | 402 | seek_ft(ft, ix[i - 1]);
|
---|
| 403 | putchar(ch);
|
---|
| 404 | if (option_mask32 & FLAG(T))
|
---|
| 405 | putchar('\t');
|
---|
| 406 | for (j = 0, col = 0; j < ix[i] - ix[i - 1]; j++) {
|
---|
| 407 | int c = fgetc(ft->ft_fp);
|
---|
| 408 | if (c == EOF) {
|
---|
[1765] | 409 | printf("\n\\ No newline at end of file\n");
|
---|
| 410 | return;
|
---|
| 411 | }
|
---|
[2725] | 412 | ft->ft_pos++;
|
---|
| 413 | if (c == '\t' && (option_mask32 & FLAG(t)))
|
---|
| 414 | do putchar(' '); while (++col & 7);
|
---|
| 415 | else {
|
---|
[1765] | 416 | putchar(c);
|
---|
| 417 | col++;
|
---|
| 418 | }
|
---|
| 419 | }
|
---|
| 420 | }
|
---|
| 421 | }
|
---|
| 422 |
|
---|
[2725] | 423 | /* Creates the match vector J, where J[i] is the index
|
---|
| 424 | * of the line in the new file corresponding to the line i
|
---|
| 425 | * in the old file. Lines start at 1 instead of 0, that value
|
---|
| 426 | * being used instead to denote no corresponding line.
|
---|
| 427 | * This vector is dynamically allocated and must be freed by the caller.
|
---|
| 428 | *
|
---|
| 429 | * * fp is an input parameter, where fp[0] and fp[1] are the open
|
---|
| 430 | * old file and new file respectively.
|
---|
| 431 | * * nlen is an output variable, where nlen[0] and nlen[1]
|
---|
| 432 | * gets the number of lines in the old and new file respectively.
|
---|
| 433 | * * ix is an output variable, where ix[0] and ix[1] gets
|
---|
| 434 | * assigned dynamically allocated vectors of the offsets of the lines
|
---|
| 435 | * of the old and new file respectively. These must be freed by the caller.
|
---|
| 436 | */
|
---|
| 437 | static NOINLINE int *create_J(FILE_and_pos_t ft[2], int nlen[2], off_t *ix[2])
|
---|
[1765] | 438 | {
|
---|
[2725] | 439 | int *J, slen[2], *class, *member;
|
---|
| 440 | struct line *nfile[2], *sfile[2];
|
---|
| 441 | int pref = 0, suff = 0, i, j, delta;
|
---|
[1765] | 442 |
|
---|
[2725] | 443 | /* Lines of both files are hashed, and in the process
|
---|
| 444 | * their offsets are stored in the array ix[fileno]
|
---|
| 445 | * where fileno == 0 points to the old file, and
|
---|
| 446 | * fileno == 1 points to the new one.
|
---|
| 447 | */
|
---|
| 448 | for (i = 0; i < 2; i++) {
|
---|
| 449 | unsigned hash;
|
---|
| 450 | token_t tok;
|
---|
| 451 | size_t sz = 100;
|
---|
| 452 | nfile[i] = xmalloc((sz + 3) * sizeof(nfile[i][0]));
|
---|
| 453 | /* ft gets here without the correct position, cant use seek_ft */
|
---|
| 454 | ft[i].ft_pos = 0;
|
---|
| 455 | fseeko(ft[i].ft_fp, 0, SEEK_SET);
|
---|
[1765] | 456 |
|
---|
[2725] | 457 | nlen[i] = 0;
|
---|
| 458 | /* We could zalloc nfile, but then zalloc starts showing in gprof at ~1% */
|
---|
| 459 | nfile[i][0].offset = 0;
|
---|
| 460 | goto start; /* saves code */
|
---|
| 461 | while (1) {
|
---|
| 462 | tok = read_token(&ft[i], tok);
|
---|
| 463 | if (!(tok & TOK_EMPTY)) {
|
---|
| 464 | /* Hash algorithm taken from Robert Sedgewick, Algorithms in C, 3d ed., p 578. */
|
---|
| 465 | /*hash = hash * 128 - hash + TOK2CHAR(tok);
|
---|
| 466 | * gcc insists on optimizing above to "hash * 127 + ...", thus... */
|
---|
| 467 | unsigned o = hash - TOK2CHAR(tok);
|
---|
| 468 | hash = hash * 128 - o; /* we want SPEED here */
|
---|
| 469 | continue;
|
---|
| 470 | }
|
---|
| 471 | if (nlen[i]++ == sz) {
|
---|
| 472 | sz = sz * 3 / 2;
|
---|
| 473 | nfile[i] = xrealloc(nfile[i], (sz + 3) * sizeof(nfile[i][0]));
|
---|
| 474 | }
|
---|
| 475 | /* line_compar needs hashes fit into positive int */
|
---|
| 476 | nfile[i][nlen[i]].value = hash & INT_MAX;
|
---|
| 477 | /* like ftello(ft[i].ft_fp) but faster (avoids lseek syscall) */
|
---|
| 478 | nfile[i][nlen[i]].offset = ft[i].ft_pos;
|
---|
| 479 | if (tok & TOK_EOF) {
|
---|
| 480 | /* EOF counts as a token, so we have to adjust it here */
|
---|
| 481 | nfile[i][nlen[i]].offset++;
|
---|
| 482 | break;
|
---|
| 483 | }
|
---|
| 484 | start:
|
---|
| 485 | hash = tok = 0;
|
---|
[1765] | 486 | }
|
---|
[2725] | 487 | /* Exclude lone EOF line from the end of the file, to make fetch()'s job easier */
|
---|
| 488 | if (nfile[i][nlen[i]].offset - nfile[i][nlen[i] - 1].offset == 1)
|
---|
| 489 | nlen[i]--;
|
---|
| 490 | /* Now we copy the line offsets into ix */
|
---|
| 491 | ix[i] = xmalloc((nlen[i] + 2) * sizeof(ix[i][0]));
|
---|
| 492 | for (j = 0; j < nlen[i] + 1; j++)
|
---|
| 493 | ix[i][j] = nfile[i][j].offset;
|
---|
[1765] | 494 | }
|
---|
| 495 |
|
---|
[2725] | 496 | /* length of prefix and suffix is calculated */
|
---|
| 497 | for (; pref < nlen[0] && pref < nlen[1] &&
|
---|
| 498 | nfile[0][pref + 1].value == nfile[1][pref + 1].value;
|
---|
| 499 | pref++);
|
---|
| 500 | for (; suff < nlen[0] - pref && suff < nlen[1] - pref &&
|
---|
| 501 | nfile[0][nlen[0] - suff].value == nfile[1][nlen[1] - suff].value;
|
---|
| 502 | suff++);
|
---|
| 503 | /* Arrays are pruned by the suffix and prefix length,
|
---|
| 504 | * the result being sorted and stored in sfile[fileno],
|
---|
| 505 | * and their sizes are stored in slen[fileno]
|
---|
[1765] | 506 | */
|
---|
[2725] | 507 | for (j = 0; j < 2; j++) {
|
---|
| 508 | sfile[j] = nfile[j] + pref;
|
---|
| 509 | slen[j] = nlen[j] - pref - suff;
|
---|
| 510 | for (i = 0; i <= slen[j]; i++)
|
---|
| 511 | sfile[j][i].serial = i;
|
---|
| 512 | qsort(sfile[j] + 1, slen[j], sizeof(*sfile[j]), line_compar);
|
---|
| 513 | }
|
---|
| 514 | /* nfile arrays are reused to reduce memory pressure
|
---|
| 515 | * The #if zeroed out section performs the same task as the
|
---|
| 516 | * one in the #else section.
|
---|
| 517 | * Peak memory usage is higher, but one array copy is avoided
|
---|
| 518 | * by not using unsort()
|
---|
| 519 | */
|
---|
| 520 | #if 0
|
---|
| 521 | member = xmalloc((slen[1] + 2) * sizeof(member[0]));
|
---|
| 522 | equiv(sfile[0], slen[0], sfile[1], slen[1], member);
|
---|
| 523 | free(nfile[1]);
|
---|
[1765] | 524 |
|
---|
[2725] | 525 | class = xmalloc((slen[0] + 1) * sizeof(class[0]));
|
---|
| 526 | for (i = 1; i <= slen[0]; i++) /* Unsorting */
|
---|
| 527 | class[sfile[0][i].serial] = sfile[0][i].value;
|
---|
| 528 | free(nfile[0]);
|
---|
[1765] | 529 | #else
|
---|
[2725] | 530 | member = (int *)nfile[1];
|
---|
| 531 | equiv(sfile[0], slen[0], sfile[1], slen[1], member);
|
---|
| 532 | member = xrealloc(member, (slen[1] + 2) * sizeof(member[0]));
|
---|
| 533 |
|
---|
| 534 | class = (int *)nfile[0];
|
---|
| 535 | unsort(sfile[0], slen[0], (int *)nfile[0]);
|
---|
| 536 | class = xrealloc(class, (slen[0] + 2) * sizeof(class[0]));
|
---|
[1765] | 537 | #endif
|
---|
[2725] | 538 | J = xmalloc((nlen[0] + 2) * sizeof(J[0]));
|
---|
| 539 | /* The elements of J which fall inside the prefix and suffix regions
|
---|
| 540 | * are marked as unchanged, while the ones which fall outside
|
---|
| 541 | * are initialized with 0 (no matches), so that function stone can
|
---|
| 542 | * then assign them their right values
|
---|
| 543 | */
|
---|
| 544 | for (i = 0, delta = nlen[1] - nlen[0]; i <= nlen[0]; i++)
|
---|
| 545 | J[i] = i <= pref ? i :
|
---|
| 546 | i > (nlen[0] - suff) ? (i + delta) : 0;
|
---|
| 547 | /* Here the magic is performed */
|
---|
| 548 | stone(class, slen[0], member, J, pref);
|
---|
| 549 | J[nlen[0] + 1] = nlen[1] + 1;
|
---|
[1765] | 550 |
|
---|
[2725] | 551 | free(class);
|
---|
| 552 | free(member);
|
---|
[1765] | 553 |
|
---|
[2725] | 554 | /* Both files are rescanned, in an effort to find any lines
|
---|
| 555 | * which, due to limitations intrinsic to any hashing algorithm,
|
---|
| 556 | * are different but ended up confounded as the same
|
---|
| 557 | */
|
---|
| 558 | for (i = 1; i <= nlen[0]; i++) {
|
---|
| 559 | if (!J[i])
|
---|
| 560 | continue;
|
---|
[1765] | 561 |
|
---|
[2725] | 562 | seek_ft(&ft[0], ix[0][i - 1]);
|
---|
| 563 | seek_ft(&ft[1], ix[1][J[i] - 1]);
|
---|
[1765] | 564 |
|
---|
[2725] | 565 | for (j = J[i]; i <= nlen[0] && J[i] == j; i++, j++) {
|
---|
| 566 | token_t tok0 = 0, tok1 = 0;
|
---|
| 567 | do {
|
---|
| 568 | tok0 = read_token(&ft[0], tok0);
|
---|
| 569 | tok1 = read_token(&ft[1], tok1);
|
---|
[1765] | 570 |
|
---|
[2725] | 571 | if (((tok0 ^ tok1) & TOK_EMPTY) != 0 /* one is empty (not both) */
|
---|
| 572 | || (!(tok0 & TOK_EMPTY) && TOK2CHAR(tok0) != TOK2CHAR(tok1))
|
---|
| 573 | ) {
|
---|
| 574 | J[i] = 0; /* Break the correspondence */
|
---|
| 575 | }
|
---|
| 576 | } while (!(tok0 & tok1 & TOK_EMPTY));
|
---|
| 577 | }
|
---|
[1765] | 578 | }
|
---|
| 579 |
|
---|
[2725] | 580 | return J;
|
---|
[1765] | 581 | }
|
---|
| 582 |
|
---|
[2725] | 583 | static bool diff(FILE* fp[2], char *file[2])
|
---|
[1765] | 584 | {
|
---|
[2725] | 585 | int nlen[2];
|
---|
| 586 | off_t *ix[2];
|
---|
| 587 | FILE_and_pos_t ft[2];
|
---|
| 588 | typedef struct { int a, b; } vec_t[2];
|
---|
| 589 | vec_t *vec = NULL;
|
---|
| 590 | int i = 1, j, k, idx = -1;
|
---|
| 591 | bool anychange = false;
|
---|
| 592 | int *J;
|
---|
[1765] | 593 |
|
---|
[2725] | 594 | ft[0].ft_fp = fp[0];
|
---|
| 595 | ft[1].ft_fp = fp[1];
|
---|
| 596 | /* note that ft[i].ft_pos is unintitalized, create_J()
|
---|
| 597 | * must not assume otherwise */
|
---|
| 598 | J = create_J(ft, nlen, ix);
|
---|
[1765] | 599 |
|
---|
[2725] | 600 | do {
|
---|
| 601 | bool nonempty = false;
|
---|
[1765] | 602 |
|
---|
[2725] | 603 | while (1) {
|
---|
| 604 | vec_t v;
|
---|
[1765] | 605 |
|
---|
[2725] | 606 | for (v[0].a = i; v[0].a <= nlen[0] && J[v[0].a] == J[v[0].a - 1] + 1; v[0].a++)
|
---|
| 607 | continue;
|
---|
| 608 | v[1].a = J[v[0].a - 1] + 1;
|
---|
[1765] | 609 |
|
---|
[2725] | 610 | for (v[0].b = v[0].a - 1; v[0].b < nlen[0] && !J[v[0].b + 1]; v[0].b++)
|
---|
| 611 | continue;
|
---|
| 612 | v[1].b = J[v[0].b + 1] - 1;
|
---|
| 613 | /*
|
---|
| 614 | * Indicate that there is a difference between lines a and b of the 'from' file
|
---|
| 615 | * to get to lines c to d of the 'to' file. If a is greater than b then there
|
---|
| 616 | * are no lines in the 'from' file involved and this means that there were
|
---|
| 617 | * lines appended (beginning at b). If c is greater than d then there are
|
---|
| 618 | * lines missing from the 'to' file.
|
---|
| 619 | */
|
---|
| 620 | if (v[0].a <= v[0].b || v[1].a <= v[1].b) {
|
---|
| 621 | /*
|
---|
| 622 | * If this change is more than 'context' lines from the
|
---|
| 623 | * previous change, dump the record and reset it.
|
---|
| 624 | */
|
---|
| 625 | int ct = (2 * opt_U_context) + 1;
|
---|
| 626 | if (idx >= 0
|
---|
| 627 | && v[0].a > vec[idx][0].b + ct
|
---|
| 628 | && v[1].a > vec[idx][1].b + ct
|
---|
| 629 | ) {
|
---|
| 630 | break;
|
---|
| 631 | }
|
---|
[1765] | 632 |
|
---|
[2725] | 633 | for (j = 0; j < 2; j++)
|
---|
| 634 | for (k = v[j].a; k < v[j].b; k++)
|
---|
| 635 | nonempty |= (ix[j][k+1] - ix[j][k] != 1);
|
---|
[1765] | 636 |
|
---|
[2725] | 637 | vec = xrealloc_vector(vec, 6, ++idx);
|
---|
| 638 | memcpy(vec[idx], v, sizeof(v));
|
---|
| 639 | }
|
---|
[1765] | 640 |
|
---|
[2725] | 641 | i = v[0].b + 1;
|
---|
| 642 | if (i > nlen[0])
|
---|
| 643 | break;
|
---|
| 644 | J[v[0].b] = v[1].b;
|
---|
| 645 | }
|
---|
| 646 | if (idx < 0 || ((option_mask32 & FLAG(B)) && !nonempty))
|
---|
| 647 | goto cont;
|
---|
| 648 | if (!(option_mask32 & FLAG(q))) {
|
---|
| 649 | int lowa;
|
---|
| 650 | vec_t span, *cvp = vec;
|
---|
[1765] | 651 |
|
---|
[2725] | 652 | if (!anychange) {
|
---|
| 653 | /* Print the context/unidiff header first time through */
|
---|
| 654 | printf("--- %s\n", label[0] ? label[0] : file[0]);
|
---|
| 655 | printf("+++ %s\n", label[1] ? label[1] : file[1]);
|
---|
| 656 | }
|
---|
[1765] | 657 |
|
---|
[2725] | 658 | printf("@@");
|
---|
| 659 | for (j = 0; j < 2; j++) {
|
---|
| 660 | int a = span[j].a = MAX(1, (*cvp)[j].a - opt_U_context);
|
---|
| 661 | int b = span[j].b = MIN(nlen[j], vec[idx][j].b + opt_U_context);
|
---|
[1765] | 662 |
|
---|
[2725] | 663 | printf(" %c%d", j ? '+' : '-', MIN(a, b));
|
---|
| 664 | if (a == b)
|
---|
| 665 | continue;
|
---|
| 666 | printf(",%d", (a < b) ? b - a + 1 : 0);
|
---|
| 667 | }
|
---|
| 668 | printf(" @@\n");
|
---|
| 669 | /*
|
---|
| 670 | * Output changes in "unified" diff format--the old and new lines
|
---|
| 671 | * are printed together.
|
---|
| 672 | */
|
---|
| 673 | for (lowa = span[0].a; ; lowa = (*cvp++)[0].b + 1) {
|
---|
| 674 | bool end = cvp > &vec[idx];
|
---|
| 675 | fetch(&ft[0], ix[0], lowa, end ? span[0].b : (*cvp)[0].a - 1, ' ');
|
---|
| 676 | if (end)
|
---|
| 677 | break;
|
---|
| 678 | for (j = 0; j < 2; j++)
|
---|
| 679 | fetch(&ft[j], ix[j], (*cvp)[j].a, (*cvp)[j].b, j ? '+' : '-');
|
---|
| 680 | }
|
---|
| 681 | }
|
---|
| 682 | anychange = true;
|
---|
| 683 | cont:
|
---|
| 684 | idx = -1;
|
---|
| 685 | } while (i <= nlen[0]);
|
---|
[1765] | 686 |
|
---|
[2725] | 687 | free(vec);
|
---|
| 688 | free(ix[0]);
|
---|
| 689 | free(ix[1]);
|
---|
| 690 | free(J);
|
---|
| 691 | return anychange;
|
---|
[1765] | 692 | }
|
---|
| 693 |
|
---|
[2725] | 694 | static int diffreg(char *file[2])
|
---|
[1765] | 695 | {
|
---|
[3232] | 696 | FILE *fp[2];
|
---|
[2725] | 697 | bool binary = false, differ = false;
|
---|
| 698 | int status = STATUS_SAME, i;
|
---|
[1765] | 699 |
|
---|
[3232] | 700 | fp[0] = stdin;
|
---|
| 701 | fp[1] = stdin;
|
---|
[2725] | 702 | for (i = 0; i < 2; i++) {
|
---|
| 703 | int fd = open_or_warn_stdin(file[i]);
|
---|
| 704 | if (fd == -1)
|
---|
| 705 | goto out;
|
---|
| 706 | /* Our diff implementation is using seek.
|
---|
| 707 | * When we meet non-seekable file, we must make a temp copy.
|
---|
| 708 | */
|
---|
| 709 | if (lseek(fd, 0, SEEK_SET) == -1 && errno == ESPIPE) {
|
---|
| 710 | char name[] = "/tmp/difXXXXXX";
|
---|
| 711 | int fd_tmp = xmkstemp(name);
|
---|
[1765] | 712 |
|
---|
[2725] | 713 | unlink(name);
|
---|
| 714 | if (bb_copyfd_eof(fd, fd_tmp) < 0)
|
---|
| 715 | xfunc_die();
|
---|
| 716 | if (fd) /* Prevents closing of stdin */
|
---|
| 717 | close(fd);
|
---|
| 718 | fd = fd_tmp;
|
---|
[1765] | 719 | }
|
---|
[2725] | 720 | fp[i] = fdopen(fd, "r");
|
---|
[1765] | 721 | }
|
---|
[2725] | 722 |
|
---|
| 723 | while (1) {
|
---|
| 724 | const size_t sz = COMMON_BUFSIZE / 2;
|
---|
| 725 | char *const buf0 = bb_common_bufsiz1;
|
---|
| 726 | char *const buf1 = buf0 + sz;
|
---|
| 727 | int j, k;
|
---|
| 728 | i = fread(buf0, 1, sz, fp[0]);
|
---|
| 729 | j = fread(buf1, 1, sz, fp[1]);
|
---|
| 730 | if (i != j) {
|
---|
| 731 | differ = true;
|
---|
| 732 | i = MIN(i, j);
|
---|
[1765] | 733 | }
|
---|
[2725] | 734 | if (i == 0)
|
---|
| 735 | break;
|
---|
| 736 | for (k = 0; k < i; k++) {
|
---|
| 737 | if (!buf0[k] || !buf1[k])
|
---|
| 738 | binary = true;
|
---|
| 739 | if (buf0[k] != buf1[k])
|
---|
| 740 | differ = true;
|
---|
| 741 | }
|
---|
[1765] | 742 | }
|
---|
[2725] | 743 | if (differ) {
|
---|
| 744 | if (binary && !(option_mask32 & FLAG(a)))
|
---|
| 745 | status = STATUS_BINARY;
|
---|
| 746 | else if (diff(fp, file))
|
---|
| 747 | status = STATUS_DIFFER;
|
---|
[1765] | 748 | }
|
---|
[2725] | 749 | if (status != STATUS_SAME)
|
---|
| 750 | exit_status |= 1;
|
---|
| 751 | out:
|
---|
| 752 | fclose_if_not_stdin(fp[0]);
|
---|
| 753 | fclose_if_not_stdin(fp[1]);
|
---|
[1765] | 754 |
|
---|
[2725] | 755 | return status;
|
---|
[1765] | 756 | }
|
---|
| 757 |
|
---|
[2725] | 758 | static void print_status(int status, char *path[2])
|
---|
[1765] | 759 | {
|
---|
[2725] | 760 | switch (status) {
|
---|
| 761 | case STATUS_BINARY:
|
---|
| 762 | case STATUS_DIFFER:
|
---|
| 763 | if ((option_mask32 & FLAG(q)) || status == STATUS_BINARY)
|
---|
| 764 | printf("Files %s and %s differ\n", path[0], path[1]);
|
---|
| 765 | break;
|
---|
| 766 | case STATUS_SAME:
|
---|
| 767 | if (option_mask32 & FLAG(s))
|
---|
| 768 | printf("Files %s and %s are identical\n", path[0], path[1]);
|
---|
| 769 | break;
|
---|
| 770 | }
|
---|
[1765] | 771 | }
|
---|
| 772 |
|
---|
[2725] | 773 | #if ENABLE_FEATURE_DIFF_DIR
|
---|
| 774 | struct dlist {
|
---|
| 775 | size_t len;
|
---|
| 776 | int s, e;
|
---|
| 777 | char **dl;
|
---|
| 778 | };
|
---|
[1765] | 779 |
|
---|
| 780 | /* This function adds a filename to dl, the directory listing. */
|
---|
[2725] | 781 | static int FAST_FUNC add_to_dirlist(const char *filename,
|
---|
| 782 | struct stat *sb UNUSED_PARAM,
|
---|
| 783 | void *userdata, int depth UNUSED_PARAM)
|
---|
[1765] | 784 | {
|
---|
[2725] | 785 | struct dlist *const l = userdata;
|
---|
| 786 | const char *file = filename + l->len;
|
---|
| 787 | while (*file == '/')
|
---|
| 788 | file++;
|
---|
| 789 | l->dl = xrealloc_vector(l->dl, 6, l->e);
|
---|
| 790 | l->dl[l->e] = xstrdup(file);
|
---|
| 791 | l->e++;
|
---|
[1765] | 792 | return TRUE;
|
---|
| 793 | }
|
---|
| 794 |
|
---|
[2725] | 795 | /* If recursion is not set, this function adds the directory
|
---|
| 796 | * to the list and prevents recursive_action from recursing into it.
|
---|
| 797 | */
|
---|
| 798 | static int FAST_FUNC skip_dir(const char *filename,
|
---|
| 799 | struct stat *sb, void *userdata,
|
---|
| 800 | int depth)
|
---|
[1765] | 801 | {
|
---|
[2725] | 802 | if (!(option_mask32 & FLAG(r)) && depth) {
|
---|
| 803 | add_to_dirlist(filename, sb, userdata, depth);
|
---|
| 804 | return SKIP;
|
---|
| 805 | }
|
---|
| 806 | if (!(option_mask32 & FLAG(N))) {
|
---|
| 807 | /* -r without -N: no need to recurse into dirs
|
---|
| 808 | * which do not exist on the "other side".
|
---|
| 809 | * Testcase: diff -r /tmp /
|
---|
| 810 | * (it would recurse deep into /proc without this code) */
|
---|
| 811 | struct dlist *const l = userdata;
|
---|
| 812 | filename += l->len;
|
---|
| 813 | if (filename[0]) {
|
---|
| 814 | struct stat osb;
|
---|
| 815 | char *othername = concat_path_file(G.other_dir, filename);
|
---|
| 816 | int r = stat(othername, &osb);
|
---|
| 817 | free(othername);
|
---|
| 818 | if (r != 0 || !S_ISDIR(osb.st_mode)) {
|
---|
| 819 | /* other dir doesn't have similarly named
|
---|
[3232] | 820 | * directory, don't recurse; return 1 upon
|
---|
| 821 | * exit, just like diffutils' diff */
|
---|
| 822 | exit_status |= 1;
|
---|
[2725] | 823 | return SKIP;
|
---|
| 824 | }
|
---|
[1765] | 825 | }
|
---|
| 826 | }
|
---|
[2725] | 827 | return TRUE;
|
---|
[1765] | 828 | }
|
---|
| 829 |
|
---|
[2725] | 830 | static void diffdir(char *p[2], const char *s_start)
|
---|
[1765] | 831 | {
|
---|
[2725] | 832 | struct dlist list[2];
|
---|
| 833 | int i;
|
---|
[1765] | 834 |
|
---|
[2725] | 835 | memset(&list, 0, sizeof(list));
|
---|
| 836 | for (i = 0; i < 2; i++) {
|
---|
| 837 | /*list[i].s = list[i].e = 0; - memset did it */
|
---|
| 838 | /*list[i].dl = NULL; */
|
---|
[1765] | 839 |
|
---|
[2725] | 840 | G.other_dir = p[1 - i];
|
---|
| 841 | /* We need to trim root directory prefix.
|
---|
| 842 | * Using list.len to specify its length,
|
---|
| 843 | * add_to_dirlist will remove it. */
|
---|
| 844 | list[i].len = strlen(p[i]);
|
---|
| 845 | recursive_action(p[i], ACTION_RECURSE | ACTION_FOLLOWLINKS,
|
---|
[3232] | 846 | add_to_dirlist, skip_dir, &list[i], 0);
|
---|
[2725] | 847 | /* Sort dl alphabetically.
|
---|
| 848 | * GNU diff does this ignoring any number of trailing dots.
|
---|
| 849 | * We don't, so for us dotted files almost always are
|
---|
| 850 | * first on the list.
|
---|
| 851 | */
|
---|
| 852 | qsort_string_vector(list[i].dl, list[i].e);
|
---|
| 853 | /* If -S was set, find the starting point. */
|
---|
| 854 | if (!s_start)
|
---|
| 855 | continue;
|
---|
| 856 | while (list[i].s < list[i].e && strcmp(list[i].dl[list[i].s], s_start) < 0)
|
---|
| 857 | list[i].s++;
|
---|
[1765] | 858 | }
|
---|
| 859 | /* Now that both dirlist1 and dirlist2 contain sorted directory
|
---|
| 860 | * listings, we can start to go through dirlist1. If both listings
|
---|
| 861 | * contain the same file, then do a normal diff. Otherwise, behaviour
|
---|
| 862 | * is determined by whether the -N flag is set. */
|
---|
[2725] | 863 | while (1) {
|
---|
| 864 | char *dp[2];
|
---|
| 865 | int pos;
|
---|
| 866 | int k;
|
---|
| 867 |
|
---|
| 868 | dp[0] = list[0].s < list[0].e ? list[0].dl[list[0].s] : NULL;
|
---|
| 869 | dp[1] = list[1].s < list[1].e ? list[1].dl[list[1].s] : NULL;
|
---|
| 870 | if (!dp[0] && !dp[1])
|
---|
| 871 | break;
|
---|
| 872 | pos = !dp[0] ? 1 : (!dp[1] ? -1 : strcmp(dp[0], dp[1]));
|
---|
| 873 | k = pos > 0;
|
---|
[3232] | 874 | if (pos && !(option_mask32 & FLAG(N))) {
|
---|
[2725] | 875 | printf("Only in %s: %s\n", p[k], dp[k]);
|
---|
[3232] | 876 | exit_status |= 1;
|
---|
| 877 | } else {
|
---|
[2725] | 878 | char *fullpath[2], *path[2]; /* if -N */
|
---|
| 879 |
|
---|
| 880 | for (i = 0; i < 2; i++) {
|
---|
| 881 | if (pos == 0 || i == k) {
|
---|
| 882 | path[i] = fullpath[i] = concat_path_file(p[i], dp[i]);
|
---|
| 883 | stat(fullpath[i], &stb[i]);
|
---|
| 884 | } else {
|
---|
| 885 | fullpath[i] = concat_path_file(p[i], dp[1 - i]);
|
---|
| 886 | path[i] = (char *)bb_dev_null;
|
---|
| 887 | }
|
---|
| 888 | }
|
---|
| 889 | if (pos)
|
---|
| 890 | stat(fullpath[k], &stb[1 - k]);
|
---|
| 891 |
|
---|
| 892 | if (S_ISDIR(stb[0].st_mode) && S_ISDIR(stb[1].st_mode))
|
---|
| 893 | printf("Common subdirectories: %s and %s\n", fullpath[0], fullpath[1]);
|
---|
| 894 | else if (!S_ISREG(stb[0].st_mode) && !S_ISDIR(stb[0].st_mode))
|
---|
| 895 | printf("File %s is not a regular file or directory and was skipped\n", fullpath[0]);
|
---|
| 896 | else if (!S_ISREG(stb[1].st_mode) && !S_ISDIR(stb[1].st_mode))
|
---|
| 897 | printf("File %s is not a regular file or directory and was skipped\n", fullpath[1]);
|
---|
| 898 | else if (S_ISDIR(stb[0].st_mode) != S_ISDIR(stb[1].st_mode)) {
|
---|
| 899 | if (S_ISDIR(stb[0].st_mode))
|
---|
| 900 | printf("File %s is a %s while file %s is a %s\n", fullpath[0], "directory", fullpath[1], "regular file");
|
---|
| 901 | else
|
---|
| 902 | printf("File %s is a %s while file %s is a %s\n", fullpath[0], "regular file", fullpath[1], "directory");
|
---|
| 903 | } else
|
---|
| 904 | print_status(diffreg(path), fullpath);
|
---|
| 905 |
|
---|
| 906 | free(fullpath[0]);
|
---|
| 907 | free(fullpath[1]);
|
---|
| 908 | }
|
---|
| 909 | free(dp[k]);
|
---|
| 910 | list[k].s++;
|
---|
[1765] | 911 | if (pos == 0) {
|
---|
[2725] | 912 | free(dp[1 - k]);
|
---|
| 913 | list[1 - k].s++;
|
---|
[1765] | 914 | }
|
---|
| 915 | }
|
---|
[2725] | 916 | if (ENABLE_FEATURE_CLEAN_UP) {
|
---|
| 917 | free(list[0].dl);
|
---|
| 918 | free(list[1].dl);
|
---|
| 919 | }
|
---|
[1765] | 920 | }
|
---|
| 921 | #endif
|
---|
| 922 |
|
---|
[2725] | 923 | #if ENABLE_FEATURE_DIFF_LONG_OPTIONS
|
---|
| 924 | static const char diff_longopts[] ALIGN1 =
|
---|
| 925 | "ignore-case\0" No_argument "i"
|
---|
| 926 | "ignore-tab-expansion\0" No_argument "E"
|
---|
| 927 | "ignore-space-change\0" No_argument "b"
|
---|
| 928 | "ignore-all-space\0" No_argument "w"
|
---|
| 929 | "ignore-blank-lines\0" No_argument "B"
|
---|
| 930 | "text\0" No_argument "a"
|
---|
| 931 | "unified\0" Required_argument "U"
|
---|
| 932 | "label\0" Required_argument "L"
|
---|
| 933 | "show-c-function\0" No_argument "p"
|
---|
| 934 | "brief\0" No_argument "q"
|
---|
| 935 | "expand-tabs\0" No_argument "t"
|
---|
| 936 | "initial-tab\0" No_argument "T"
|
---|
| 937 | "recursive\0" No_argument "r"
|
---|
| 938 | "new-file\0" No_argument "N"
|
---|
| 939 | "report-identical-files\0" No_argument "s"
|
---|
| 940 | "starting-file\0" Required_argument "S"
|
---|
| 941 | "minimal\0" No_argument "d"
|
---|
| 942 | ;
|
---|
| 943 | #endif
|
---|
[1765] | 944 |
|
---|
[2725] | 945 | int diff_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
|
---|
| 946 | int diff_main(int argc UNUSED_PARAM, char **argv)
|
---|
[1765] | 947 | {
|
---|
[2725] | 948 | int gotstdin = 0, i;
|
---|
| 949 | char *file[2], *s_start = NULL;
|
---|
[1765] | 950 | llist_t *L_arg = NULL;
|
---|
| 951 |
|
---|
| 952 | INIT_G();
|
---|
| 953 |
|
---|
[2725] | 954 | /* exactly 2 params; collect multiple -L <label>; -U N */
|
---|
| 955 | opt_complementary = "=2:L::U+";
|
---|
| 956 | #if ENABLE_FEATURE_DIFF_LONG_OPTIONS
|
---|
| 957 | applet_long_options = diff_longopts;
|
---|
| 958 | #endif
|
---|
| 959 | getopt32(argv, "abdiL:NqrsS:tTU:wupBE",
|
---|
| 960 | &L_arg, &s_start, &opt_U_context);
|
---|
[1765] | 961 | argv += optind;
|
---|
[2725] | 962 | while (L_arg)
|
---|
| 963 | label[!!label[0]] = llist_pop(&L_arg);
|
---|
| 964 | xfunc_error_retval = 2;
|
---|
| 965 | for (i = 0; i < 2; i++) {
|
---|
| 966 | file[i] = argv[i];
|
---|
| 967 | /* Compat: "diff file name_which_doesnt_exist" exits with 2 */
|
---|
| 968 | if (LONE_DASH(file[i])) {
|
---|
| 969 | fstat(STDIN_FILENO, &stb[i]);
|
---|
| 970 | gotstdin++;
|
---|
| 971 | } else
|
---|
| 972 | xstat(file[i], &stb[i]);
|
---|
[1765] | 973 | }
|
---|
[2725] | 974 | xfunc_error_retval = 1;
|
---|
| 975 | if (gotstdin && (S_ISDIR(stb[0].st_mode) || S_ISDIR(stb[1].st_mode)))
|
---|
| 976 | bb_error_msg_and_die("can't compare stdin to a directory");
|
---|
[1765] | 977 |
|
---|
[3232] | 978 | /* Compare metadata to check if the files are the same physical file.
|
---|
| 979 | *
|
---|
| 980 | * Comment from diffutils source says:
|
---|
| 981 | * POSIX says that two files are identical if st_ino and st_dev are
|
---|
| 982 | * the same, but many file systems incorrectly assign the same (device,
|
---|
| 983 | * inode) pair to two distinct files, including:
|
---|
| 984 | * GNU/Linux NFS servers that export all local file systems as a
|
---|
| 985 | * single NFS file system, if a local device number (st_dev) exceeds
|
---|
| 986 | * 255, or if a local inode number (st_ino) exceeds 16777215.
|
---|
| 987 | */
|
---|
| 988 | if (ENABLE_DESKTOP
|
---|
| 989 | && stb[0].st_ino == stb[1].st_ino
|
---|
| 990 | && stb[0].st_dev == stb[1].st_dev
|
---|
| 991 | && stb[0].st_size == stb[1].st_size
|
---|
| 992 | && stb[0].st_mtime == stb[1].st_mtime
|
---|
| 993 | && stb[0].st_ctime == stb[1].st_ctime
|
---|
| 994 | && stb[0].st_mode == stb[1].st_mode
|
---|
| 995 | && stb[0].st_nlink == stb[1].st_nlink
|
---|
| 996 | && stb[0].st_uid == stb[1].st_uid
|
---|
| 997 | && stb[0].st_gid == stb[1].st_gid
|
---|
| 998 | ) {
|
---|
| 999 | /* files are physically the same; no need to compare them */
|
---|
| 1000 | return STATUS_SAME;
|
---|
| 1001 | }
|
---|
| 1002 |
|
---|
[2725] | 1003 | if (S_ISDIR(stb[0].st_mode) && S_ISDIR(stb[1].st_mode)) {
|
---|
[1765] | 1004 | #if ENABLE_FEATURE_DIFF_DIR
|
---|
[2725] | 1005 | diffdir(file, s_start);
|
---|
[1765] | 1006 | #else
|
---|
[2725] | 1007 | bb_error_msg_and_die("no support for directory comparison");
|
---|
[1765] | 1008 | #endif
|
---|
| 1009 | } else {
|
---|
[2725] | 1010 | bool dirfile = S_ISDIR(stb[0].st_mode) || S_ISDIR(stb[1].st_mode);
|
---|
| 1011 | bool dir = S_ISDIR(stb[1].st_mode);
|
---|
| 1012 | if (dirfile) {
|
---|
| 1013 | const char *slash = strrchr(file[!dir], '/');
|
---|
| 1014 | file[dir] = concat_path_file(file[dir], slash ? slash + 1 : file[!dir]);
|
---|
| 1015 | xstat(file[dir], &stb[dir]);
|
---|
[1765] | 1016 | }
|
---|
[2725] | 1017 | /* diffreg can get non-regular files here */
|
---|
| 1018 | print_status(gotstdin > 1 ? STATUS_SAME : diffreg(file), file);
|
---|
| 1019 |
|
---|
| 1020 | if (dirfile)
|
---|
| 1021 | free(file[dir]);
|
---|
[1765] | 1022 | }
|
---|
[2725] | 1023 |
|
---|
| 1024 | return exit_status;
|
---|
[1765] | 1025 | }
|
---|