Adjust Erik's change, as I don't claim copyright of the applet.
[oweals/busybox.git] / coreutils / uniq.c
index 0cccbd5e7639774fc2a22a7b5419cc8932a05a64..90686c9af48bd9c47bc1c055ba043dfd393ab700 100644 (file)
@@ -1,10 +1,8 @@
 /* vi: set sw=4 ts=4: */
 /*
- * Mini uniq implementation for busybox
+ * uniq implementation for busybox
  *
- *
- * Copyright (C) 1999,2000 by Lineo, inc.
- * Written by John Beppu <beppu@lineo.com>
+ * Copyright (C) 2003  Manuel Novoa III  <mjn3@codepoet.org>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  *
  */
 
-#include "internal.h"
+/* BB_AUDIT SUSv3 compliant */
+/* http://www.opengroup.org/onlinepubs/007904975/utilities/uniq.html */
+
 #include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
-#include <errno.h>
-
-static const char uniq_usage[] =
-       "uniq [OPTION]... [INPUT [OUTPUT]]\n"
-#ifndef BB_FEATURE_TRIVIAL_HELP
-       "\nDiscard all but one of successive identical lines from INPUT\n"
-       "(or standard input), writing to OUTPUT (or standard output).\n"
-#endif
-       ;
-
-/* max chars in line */
-#define UNIQ_MAX 4096
-
-typedef void (Print) (FILE *, const char *);
-
-typedef int (Decide) (const char *, const char *);
+#include <ctype.h>
+#include <unistd.h>
+#include "busybox.h"
+#include "libcoreutils/coreutils.h"
 
-/* container for two lines to be compared */
-typedef struct {
-       char *a;
-       char *b;
-       int recurrence;
-       FILE *in;
-       FILE *out;
-       void *func;
-} Subject;
+static const char uniq_opts[] = "f:s:cdu\0\7\3\5\1\2\4";
 
-/* set up all the variables of a uniq operation */
-static Subject *subject_init(Subject * self, FILE * in, FILE * out,
-                                                        void *func)
-{
-       self->a = NULL;
-       self->b = NULL;
-       self->in = in;
-       self->out = out;
-       self->func = func;
-       self->recurrence = 0;
-       return self;
-}
-
-/* point a and b to the appropriate lines;
- * count the recurrences (if any) of a string;
- */
-static Subject *subject_next(Subject * self)
+int uniq_main(int argc, char **argv)
 {
-       /* tmp line holders */
-       static char line[2][UNIQ_MAX];
-       static int alternator = 0;
-
-       if (fgets(line[alternator], UNIQ_MAX, self->in)) {
-               self->a = self->b;
-               self->b = line[alternator];
-               alternator ^= 1;
-               return self;
+       FILE *in, *out;
+       /* Note: Ignore the warning about dups and e0 possibly being uninitialized.
+        * They will be initialized on the fist pass of the loop (since s0 is NULL). */
+       unsigned long dups, skip_fields, skip_chars, i;
+       const char *s0, *e0, *s1, *e1, *input_filename;
+       int opt;
+       int uniq_flags = 6;             /* -u */
+
+       skip_fields = skip_chars = 0;
+
+       while ((opt = getopt(argc, argv, uniq_opts)) > 0) {
+               if (opt == 'f') {
+                       skip_fields = bb_xgetularg10(optarg);
+               } else if (opt == 's') {
+                       skip_chars = bb_xgetularg10(optarg);
+               } else if ((s0 = strchr(uniq_opts, opt)) != NULL) {
+                       uniq_flags &= s0[4];
+                       uniq_flags |= s0[7];
+               } else {
+                       bb_show_usage();
+               }
        }
 
-       return NULL;
-}
+       input_filename = *(argv += optind);
 
-static Subject *subject_last(Subject * self)
-{
-       self->a = self->b;
-       self->b = NULL;
-       return self;
-}
-
-static Subject *subject_study(Subject * self)
-{
-       if (self->a == NULL) {
-               return self;
+       in = xgetoptfile_sort_uniq(argv, "r");
+       if (*argv) {
+               ++argv;
        }
-       if (self->b == NULL) {
-               fprintf(self->out, "%s", self->a);
-               return self;
+       out = xgetoptfile_sort_uniq(argv, "w");
+       if (*argv && argv[1]) {
+               bb_show_usage();
        }
-       if (strcmp(self->a, self->b) == 0) {
-               self->recurrence++;
-       } else {
-               fprintf(self->out, "%s", self->a);
-               self->recurrence = 0;
-       }
-       return self;
-}
-
-static int
-set_file_pointers(int schema, FILE ** in, FILE ** out, char **argv)
-{
-       switch (schema) {
-       case 0:
-               *in = stdin;
-               *out = stdout;
-               break;
-       case 1:
-               *in = fopen(argv[0], "r");
-               *out = stdout;
-               break;
-       case 2:
-               *in = fopen(argv[0], "r");
-               *out = fopen(argv[1], "w");
-               break;
-       }
-       if (*in == NULL) {
-               fprintf(stderr, "uniq: %s: %s\n", argv[0], strerror(errno));
-               return errno;
-       }
-       if (*out == NULL) {
-               fprintf(stderr, "uniq: %s: %s\n", argv[1], strerror(errno));
-               return errno;
-       }
-       return 0;
-}
 
+       s0 = NULL;
 
-/* one variable is the decision algo */
-/* another variable is the printing algo */
-
-/* I don't think I have to have more than a 1 line memory 
-   this is the one constant */
-
-/* it seems like GNU/uniq only takes one or two files as an option */
-
-/* ________________________________________________________________________ */
-int uniq_main(int argc, char **argv)
-{
-       int i;
-       char opt;
-       FILE *in, *out;
-       Subject s;
-
-       /* parse argv[] */
-       for (i = 1; i < argc; i++) {
-               if (argv[i][0] == '-') {
-                       opt = argv[i][1];
-                       switch (opt) {
-                       case '-':
-                       case 'h':
-                               usage(uniq_usage);
-                       default:
-                               usage(uniq_usage);
+       /* gnu uniq ignores newlines */
+       while ((s1 = bb_get_chomped_line_from_file(in)) != NULL) {
+               e1 = s1;
+               for (i=skip_fields ; i ; i--) {
+                       e1 = bb_skip_whitespace(e1);
+                       while (*e1 && !isspace(*e1)) {
+                               ++e1;
                        }
-               } else {
-                       break;
                }
-       }
+               for (i = skip_chars ; *e1 && i ; i--) {
+                       ++e1;
+               }
+               if (s0) {
+                       if (strcmp(e0, e1) == 0) {
+                               ++dups;         /* Note: Testing for overflow seems excessive. */
+                               continue;
+                       }
+               DO_LAST:
+                       if ((dups && (uniq_flags & 2)) || (!dups && (uniq_flags & 4))) {
+                               bb_fprintf(out, "\0%7d\t" + (uniq_flags & 1), dups + 1);
+                               bb_fprintf(out, "%s\n", s0);
+                       }
+                       free((void *)s0);
+               }
 
-       /* 0 src: stdin; dst: stdout */
-       /* 1 src: file;  dst: stdout */
-       /* 2 src: file;  dst: file   */
-       if (set_file_pointers((argc - 1), &in, &out, &argv[i])) {
-               exit(1);
+               s0 = s1;
+               e0 = e1;
+               dups = 0;
        }
 
-       subject_init(&s, in, out, NULL);
-       while (subject_next(&s)) {
-               subject_study(&s);
+       if (s0) {
+               e1 = NULL;
+               goto DO_LAST;
        }
-       subject_last(&s);
-       subject_study(&s);
 
-       exit(0);
-}
+       bb_xferror(in, input_filename);
 
-/* $Id: uniq.c,v 1.10 2000/05/12 19:41:47 erik Exp $ */
+       bb_fflush_stdout_and_exit(EXIT_SUCCESS);
+}