sbase/uniq.c

142 lines
2.4 KiB
C

/* See LICENSE file for copyright and license details. */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <ctype.h>
#include "text.h"
#include "util.h"
static void uniqline(FILE *, char *);
static void uniq(FILE *, FILE *);
static void uniqfinish(FILE *);
static const char *countfmt = "";
static int dflag = 0;
static int uflag = 0;
static int fskip = 0;
static int sskip = 0;
static char *prevline = NULL;
static char *prevoffset = NULL;
static long prevlinecount = 0;
static void
usage(void)
{
eprintf("usage: %s [-c] [-d | -u] [-f fields] [-s chars]"
" [[input] output]\n", argv0);
}
int
main(int argc, char *argv[])
{
FILE *fp = stdin, *ofp = stdout;
ARGBEGIN {
case 'c':
countfmt = "%7ld ";
break;
case 'd':
dflag = 1;
break;
case 'u':
uflag = 1;
break;
case 'f':
fskip = estrtonum(EARGF(usage()), 0, INT_MAX);
break;
case 's':
sskip = estrtonum(EARGF(usage()), 0, INT_MAX);
break;
default:
usage();
} ARGEND;
if (argc == 0) {
uniq(stdin, stdout);
} else if (argc >= 1) {
if (strcmp(argv[0], "-") && !(fp = fopen(argv[0], "r")))
eprintf("fopen %s:", argv[0]);
if (argc == 2) {
if (strcmp(argv[1], "-") &&
!(ofp = fopen(argv[1], "w")))
eprintf("fopen %s:", argv[1]);
} else
eprintf("extra argument: %s\n", argv[2]);
uniq(fp, ofp);
if (fp != stdin)
fclose(fp);
} else
usage();
uniqfinish(ofp);
if (ofp != stdout)
fclose(ofp);
return 0;
}
static char *
uniqskip(char *l)
{
char *lo = l;
int f = fskip, s = sskip;
for (; f; --f) {
while (isblank(*lo))
lo++;
while (*lo && !isblank(*lo))
lo++;
}
for (; s && *lo && *lo != '\n'; --s, ++lo);
return lo;
}
static void
uniqline(FILE *ofp, char *l)
{
char *loffset = l ? uniqskip(l) : l;
int linesequel = (!l || !prevline)
? l == prevline
: !strcmp(loffset, prevoffset);
if (linesequel) {
++prevlinecount;
return;
}
if (prevline) {
if ((prevlinecount == 1 && !dflag) ||
(prevlinecount != 1 && !uflag)) {
fprintf(ofp, countfmt, prevlinecount);
fputs(prevline, ofp);
}
free(prevline);
prevline = prevoffset = NULL;
}
if (l) {
prevline = estrdup(l);
prevoffset = prevline + (loffset - l);
}
prevlinecount = 1;
}
static void
uniq(FILE *fp, FILE *ofp)
{
char *buf = NULL;
size_t size = 0;
while (getline(&buf, &size, fp) != -1)
uniqline(ofp, buf);
}
static void
uniqfinish(FILE *ofp)
{
uniqline(ofp, NULL);
}