sbase/fold.c
2015-05-21 15:43:38 +01:00

115 lines
2.0 KiB
C

/* See LICENSE file for copyright and license details. */
#include <ctype.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "util.h"
static int bflag = 0;
static int sflag = 0;
static size_t width = 80;
static void
foldline(const char *str) {
const char *p, *spacesect = NULL;
size_t col, off;
for (p = str, col = 0; *p && *p != '\n'; p++) {
if (!UTF8_POINT(*p) && !bflag)
continue;
if (col >= width) {
off = (sflag && spacesect) ? spacesect - str : p - str;
if (fwrite(str, 1, off, stdout) != off)
eprintf("fwrite <stdout>:");
putchar('\n');
spacesect = NULL;
col = 0;
p = str += off;
}
if (sflag && isspace(*p))
spacesect = p + 1;
if (!bflag && iscntrl(*p)) {
switch(*p) {
case '\b':
col -= (col > 0);
break;
case '\r':
col = 0;
break;
case '\t':
col += (col + 1) % 8;
break;
}
} else {
col++;
}
}
fputs(str, stdout);
}
static void
fold(FILE *fp, const char *fname)
{
char *buf = NULL;
size_t size = 0;
while (getline(&buf, &size, fp) > 0)
foldline(buf);
if (ferror(fp))
eprintf("getline %s:", fname);
free(buf);
}
static void
usage(void)
{
eprintf("usage: %s [-bs] [-w num | -num] [FILE ...]\n", argv0);
}
int
main(int argc, char *argv[])
{
FILE *fp;
int ret = 0;
ARGBEGIN {
case 'b':
bflag = 1;
break;
case 's':
sflag = 1;
break;
case 'w':
width = estrtonum(EARGF(usage()), 1, MIN(LLONG_MAX, SIZE_MAX));
break;
ARGNUM:
if (!(width = ARGNUMF()))
eprintf("illegal width value, too small\n");
break;
default:
usage();
} ARGEND;
if (!argc) {
fold(stdin, "<stdin>");
} else {
for (; *argv; argc--, argv++) {
if (!strcmp(*argv, "-")) {
*argv = "<stdin>";
fp = stdin;
} else if (!(fp = fopen(*argv, "r"))) {
weprintf("fopen %s:", *argv);
ret = 1;
continue;
}
fold(fp, *argv);
if (fp != stdin && fshut(fp, *argv))
ret = 1;
}
}
return !!(fshut(stdin, "<stdin>") + fshut(stdout, "<stdout>")) || ret;
}