122 lines
2.2 KiB
C
122 lines
2.2 KiB
C
/* unexpand - convert spaces to tabs Author: Terrence W. Holm */
|
|
|
|
/* Usage: unexpand [ -a ] [ file ... ] */
|
|
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <stdio.h>
|
|
|
|
#define TAB 8
|
|
|
|
|
|
int column = 0; /* Current column, retained between files */
|
|
int spaces = 0; /* Spaces since last tab stop */
|
|
int leading_blank = 1; /* Only unexpand leading blanks, */
|
|
/* Overruled by -a option */
|
|
|
|
_PROTOTYPE(int main, (int argc, char **argv));
|
|
_PROTOTYPE(void Unexpand, (FILE *f, int all));
|
|
|
|
int main(argc, argv)
|
|
int argc;
|
|
char *argv[];
|
|
|
|
{
|
|
int all = 0; /* -a flag means unexpand all spaces */
|
|
int i;
|
|
FILE *f;
|
|
|
|
if (argc > 1 && argv[1][0] == '-') {
|
|
if (strcmp(argv[1], "-a") == 0)
|
|
all = 1;
|
|
else {
|
|
fprintf(stderr, "Usage: unexpand [ -a ] [ file ... ]\n");
|
|
exit(1);
|
|
}
|
|
|
|
--argc;
|
|
++argv;
|
|
}
|
|
if (argc == 1)
|
|
Unexpand(stdin, all);
|
|
else
|
|
for (i = 1; i < argc; ++i) {
|
|
if ((f = fopen(argv[i], "r")) == NULL) {
|
|
perror(argv[i]);
|
|
exit(1);
|
|
}
|
|
Unexpand(f, all);
|
|
fclose(f);
|
|
}
|
|
|
|
|
|
/* If there are pending spaces print them. */
|
|
|
|
while (spaces > 0) {
|
|
putchar(' ');
|
|
--spaces;
|
|
}
|
|
|
|
return(0);
|
|
}
|
|
|
|
void Unexpand(f, all)
|
|
FILE *f;
|
|
int all;
|
|
|
|
{
|
|
int c;
|
|
|
|
while ((c = getc(f)) != EOF) {
|
|
if (c == ' ' && (all || leading_blank)) {
|
|
++column;
|
|
++spaces;
|
|
|
|
/* If we have white space up to a tab stop, then output */
|
|
/* A tab. If only one space is required, use a ' '. */
|
|
|
|
if (column % TAB == 0) {
|
|
if (spaces == 1)
|
|
putchar(' ');
|
|
else
|
|
putchar('\t');
|
|
|
|
spaces = 0;
|
|
}
|
|
continue;
|
|
}
|
|
|
|
/* If a tab character is encountered in the input then */
|
|
/* Simply echo it. Any accumulated spaces can only be */
|
|
/* Since the last tab stop, so ignore them. */
|
|
if (c == '\t') {
|
|
column = (column / TAB + 1) * TAB;
|
|
spaces = 0;
|
|
putchar('\t');
|
|
continue;
|
|
}
|
|
|
|
/* A non-space character is to be printed. If there */
|
|
/* Are pending spaces, then print them. There will be */
|
|
/* At most TAB-1 spaces to print. */
|
|
while (spaces > 0) {
|
|
putchar(' ');
|
|
--spaces;
|
|
}
|
|
|
|
if (c == '\n' || c == '\r') {
|
|
column = 0;
|
|
leading_blank = 1;
|
|
putchar(c);
|
|
continue;
|
|
}
|
|
if (c == '\b')
|
|
column = column > 0 ? column - 1 : 0;
|
|
else
|
|
++column;
|
|
|
|
leading_blank = 0;
|
|
putchar(c);
|
|
}
|
|
}
|