+/* vi: set sw=4 ts=4: */
/*
- * Mini sort implementation for busybox
+ * Mini uniq implementation for busybox
*
*
- * Copyright (C) 1999 by Lineo, inc.
+ * Copyright (C) 1999,2000 by Lineo, inc.
* Written by John Beppu <beppu@lineo.com>
*
* This program is free software; you can redistribute it and/or modify
#include "internal.h"
#include <stdio.h>
+#include <string.h>
+#include <errno.h>
static const char uniq_usage[] =
-"haha\n"
-;
+ "uniq [OPTION]... [INPUT [OUTPUT]]\n"
+ "Discard all but one of successive identical lines from INPUT (or\n"
+ "standard input), writing to OUTPUT (or standard output).\n"
+ "\n"
+ "\t-h\tdisplay this help and exit\n"
+
+ "\n"
+ "A field is a run of whitespace, then non-whitespace characters.\n"
+ "Fields are skipped before chars.\n";
/* max chars in line */
#define UNIQ_MAX 4096
-typedef void (Print)(FILE *, const char *);
+typedef void (Print) (FILE *, const char *);
-typedef int (Decide)(const char *, const char *);
+typedef int (Decide) (const char *, const char *);
/* container for two lines to be compared */
typedef struct {
- char *a;
- char *b;
- int recurrence;
- FILE *in;
- FILE *out;
- void *func;
+ char *a;
+ char *b;
+ int recurrence;
+ FILE *in;
+ FILE *out;
+ void *func;
} Subject;
/* set up all the variables of a uniq operation */
-static Subject *
-subject_init(Subject *self, FILE *in, FILE *out, void *func)
+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;
+ 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)
+static Subject *subject_next(Subject * self)
{
- /* tmp line holders */
- static char line[2][UNIQ_MAX];
- static int alternator = 0;
+ /* 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;
+ }
- if (fgets(line[alternator], UNIQ_MAX, self->in)) {
+ return NULL;
+}
+
+static Subject *subject_last(Subject * self)
+{
self->a = self->b;
- self->b = line[alternator];
- alternator ^= 1;
+ self->b = NULL;
return self;
- }
-
- return NULL;
}
-static Subject *
-subject_last(Subject *self)
+static Subject *subject_study(Subject * self)
{
- self->a = self->b;
- self->b = NULL;
- return self;
+ if (self->a == NULL) {
+ return self;
+ }
+ if (self->b == NULL) {
+ fprintf(self->out, "%s", self->a);
+ return self;
+ }
+ if (strcmp(self->a, self->b) == 0) {
+ self->recurrence++;
+ } else {
+ fprintf(self->out, "%s", self->a);
+ self->recurrence = 0;
+ }
+ return self;
}
-static Subject *
-subject_study(Subject *self)
+static int
+set_file_pointers(int schema, FILE ** in, FILE ** out, char **argv)
{
- if (self->a == NULL) {
- return self;
- }
- if (self->b == NULL) {
- fprintf(self->out, "%s", self->a);
- return self;
- }
- if (strcmp(self->a, self->b) == 0) {
- self->recurrence++;
- } else {
- fprintf(self->out, "%s", self->a);
- self->recurrence = 0;
- }
- return self;
+ 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;
}
+
/* one variable is the decision algo */
/* another variable is the printing algo */
/* it seems like GNU/uniq only takes one or two files as an option */
/* ________________________________________________________________________ */
-int
-uniq_main(int argc, char **argv)
+int uniq_main(int argc, char **argv)
{
- int i;
- char opt;
- FILE *in, *out;
- Subject s;
+ 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);
+ }
+ } else {
+ break;
+ }
+ }
- /* init */
- in = stdin;
- out = stdout;
+ /* 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);
+ }
- subject_init(&s, in, out, NULL);
- while (subject_next(&s)) {
- subject_study(&s);
- }
- subject_last(&s);
- subject_study(&s);
- exit(0);
-
- /* XXX : finish the tedious stuff */
-
- /* parse argv[] */
- for (i = 1; i < argc; i++) {
- if (argv[i][0] == '-') {
- opt = argv[i][1];
- switch (opt) {
- case 'h':
- usage(uniq_usage);
- default:
- usage(uniq_usage);
- }
- } else {
- break;
+ subject_init(&s, in, out, NULL);
+ while (subject_next(&s)) {
+ subject_study(&s);
}
- }
+ subject_last(&s);
+ subject_study(&s);
- exit(0);
+ exit(0);
}
-/* $Id: uniq.c,v 1.1 2000/01/06 00:48:21 beppu Exp $ */
+/* $Id: uniq.c,v 1.8 2000/04/13 01:18:56 erik Exp $ */