git/builtin/stripspace.c
Conrad Irwin 497215d881 Update documentation for stripspace
Tell the user what this command is intended for, and expand the
description of what it does.

Signed-off-by: Conrad Irwin <conrad.irwin@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-12-12 16:48:54 -08:00

89 lines
1.9 KiB
C

#include "builtin.h"
#include "cache.h"
/*
* Returns the length of a line, without trailing spaces.
*
* If the line ends with newline, it will be removed too.
*/
static size_t cleanup(char *line, size_t len)
{
while (len) {
unsigned char c = line[len - 1];
if (!isspace(c))
break;
len--;
}
return len;
}
/*
* Remove empty lines from the beginning and end
* and also trailing spaces from every line.
*
* Turn multiple consecutive empty lines between paragraphs
* into just one empty line.
*
* If the input has only empty lines and spaces,
* no output will be produced.
*
* If last line does not have a newline at the end, one is added.
*
* Enable skip_comments to skip every line starting with "#".
*/
void stripspace(struct strbuf *sb, int skip_comments)
{
int empties = 0;
size_t i, j, len, newlen;
char *eol;
/* We may have to add a newline. */
strbuf_grow(sb, 1);
for (i = j = 0; i < sb->len; i += len, j += newlen) {
eol = memchr(sb->buf + i, '\n', sb->len - i);
len = eol ? eol - (sb->buf + i) + 1 : sb->len - i;
if (skip_comments && len && sb->buf[i] == '#') {
newlen = 0;
continue;
}
newlen = cleanup(sb->buf + i, len);
/* Not just an empty line? */
if (newlen) {
if (empties > 0 && j > 0)
sb->buf[j++] = '\n';
empties = 0;
memmove(sb->buf + j, sb->buf + i, newlen);
sb->buf[newlen + j++] = '\n';
} else {
empties++;
}
}
strbuf_setlen(sb, j);
}
int cmd_stripspace(int argc, const char **argv, const char *prefix)
{
struct strbuf buf = STRBUF_INIT;
int strip_comments = 0;
if (argc == 2 && (!strcmp(argv[1], "-s") ||
!strcmp(argv[1], "--strip-comments")))
strip_comments = 1;
else if (argc > 1)
usage("git stripspace [-s | --strip-comments] < input");
if (strbuf_read(&buf, 0, 1024) < 0)
die_errno("could not read the input");
stripspace(&buf, strip_comments);
write_or_die(1, buf.buf, buf.len);
strbuf_release(&buf);
return 0;
}