xref: /third_party/toybox/toys/posix/uniq.c (revision 0f66f451) 
1/* uniq.c - report or filter out repeated lines in a file
2 *
3 * Copyright 2012 Georgi Chorbadzhiyski <georgi@unixsol.org>
4 *
5 * See http://opengroup.org/onlinepubs/9699919799/utilities/uniq.html
6
7USE_UNIQ(NEWTOY(uniq, "f#s#w#zicdu", TOYFLAG_USR|TOYFLAG_BIN))
8
9config UNIQ
10  bool "uniq"
11  default y
12  help
13    usage: uniq [-cduiz] [-w MAXCHARS] [-f FIELDS] [-s CHAR] [INFILE [OUTFILE]]
14
15    Report or filter out repeated lines in a file
16
17    -c	Show counts before each line
18    -d	Show only lines that are repeated
19    -u	Show only lines that are unique
20    -i	Ignore case when comparing lines
21    -z	Lines end with \0 not \n
22    -w	Compare maximum X chars per line
23    -f	Ignore first X fields
24    -s	Ignore first X chars
25*/
26
27#define FOR_uniq
28#include "toys.h"
29
30GLOBALS(
31  long w, s, f;
32
33  long repeats;
34)
35
36static char *skip(char *str)
37{
38  long nchars = TT.s, nfields = TT.f;
39
40  // Skip fields first
41  while (nfields--) {
42    while (*str && isspace(*str)) str++;
43    while (*str && !isspace(*str)) str++;
44  }
45  // Skip chars
46  while (*str && nchars--) str++;
47
48  return str;
49}
50
51static void print_line(FILE *f, char *line)
52{
53  if (TT.repeats ? FLAG(u) : FLAG(d)) return;
54  if (FLAG(c)) fprintf(f, "%7lu ", TT.repeats + 1);
55  fputs(line, f);
56  if (FLAG(z)) fputc(0, f);
57}
58
59void uniq_main(void)
60{
61  FILE *infile = stdin, *outfile = stdout;
62  char *thisline = 0, *prevline = 0, *tmpline, eol = '\n';
63  size_t thissize, prevsize = 0, tmpsize;
64
65  if (toys.optc >= 1) infile = xfopen(toys.optargs[0], "r");
66  if (toys.optc >= 2) outfile = xfopen(toys.optargs[1], "w");
67
68  if (FLAG(z)) eol = 0;
69
70  // If first line can't be read
71  if (getdelim(&prevline, &prevsize, eol, infile) < 0) return;
72
73  while (getdelim(&thisline, &thissize, eol, infile) > 0) {
74    int diff;
75    char *t1, *t2;
76
77    // If requested get the chosen fields + character offsets.
78    if (TT.f || TT.s) {
79      t1 = skip(thisline);
80      t2 = skip(prevline);
81    } else {
82      t1 = thisline;
83      t2 = prevline;
84    }
85
86    if (!TT.w)
87      diff = !FLAG(i) ? strcmp(t1, t2) : strcasecmp(t1, t2);
88    else diff = !FLAG(i) ? strncmp(t1, t2, TT.w) : strncasecmp(t1, t2, TT.w);
89
90    if (!diff) TT.repeats++;
91    else {
92      print_line(outfile, prevline);
93
94      TT.repeats = 0;
95
96      tmpline = prevline;
97      prevline = thisline;
98      thisline = tmpline;
99
100      tmpsize = prevsize;
101      prevsize = thissize;
102      thissize = tmpsize;
103    }
104  }
105
106  print_line(outfile, prevline);
107
108  if (CFG_TOYBOX_FREE) {
109    if (outfile != stdout) fclose(outfile);
110    if (infile != stdin) fclose(infile);
111    free(prevline);
112    free(thisline);
113  }
114}
115