sbase/fold.c

106 lines
1.7 KiB
C

/* See LICENSE file for copyright and license details. */
#include <ctype.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include "text.h"
#include "util.h"
static void fold(FILE *, long);
static void foldline(const char *, long);
static bool bflag = false;
static bool sflag = false;
static void
usage(void)
{
eprintf("usage: %s [-bs] [-w width] [FILE...]\n", argv0);
}
int
main(int argc, char *argv[])
{
long width = 80;
FILE *fp;
ARGBEGIN {
case 'b':
bflag = true;
break;
case 's':
sflag = true;
break;
case 'w':
width = estrtol(EARGF(usage()), 0);
break;
default:
usage();
} ARGEND;
if(argc == 0) {
fold(stdin, width);
} else for(; argc > 0; argc--, argv++) {
if(!(fp = fopen(argv[0], "r")))
eprintf("fopen %s:", argv[0]);
fold(fp, width);
fclose(fp);
}
return 0;
}
void
fold(FILE *fp, long width)
{
char *buf = NULL;
size_t size = 0;
while(afgets(&buf, &size, fp))
foldline(buf, width);
free(buf);
}
void
foldline(const char *str, long width)
{
bool space;
long col, j;
size_t i = 0, n = 0;
do {
space = false;
for(j = i, col = 0; str[j] && col <= width; j++) {
if(!UTF8_POINT(str[j]) && !bflag)
continue;
if(sflag && isspace(str[j])) {
space = true;
n = j+1;
}
else if(!space)
n = j;
if(!bflag && iscntrl(str[j]))
switch(str[j]) {
case '\b':
col--;
break;
case '\r':
col = 0;
break;
case '\t':
col += (col+1) % 8;
break;
}
else
col++;
}
if(fwrite(&str[i], 1, n-i, stdout) != n-i)
eprintf("<stdout>: write error:");
if(str[n])
putchar('\n');
} while(str[i = n] && str[i] != '\n');
}