hush/coreutils/comm.c
Rob Landley d921b2ecc0 Remove bb_ prefixes from xfuncs.c (and a few other places), consolidate
things like xasprintf() into xfuncs.c, remove xprint_file_by_name() (it only
had one user), clean up lots of #includes...  General cleanup pass.  What I've
been doing for the last couple days.

And it conflicts!  I've removed httpd.c from this checkin due to somebody else
touching that file.  It builds for me.  I have to catch a bus.  (Now you know
why I'm looking forward to Mercurial.)
2006-08-03 15:41:12 +00:00

127 lines
2.7 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Mini comm implementation for busybox
*
* Copyright (C) 2005 by Robert Sullivan <cogito.ergo.cogito@gmail.com>
*
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
#include "busybox.h"
#define COMM_OPT_1 0x01
#define COMM_OPT_2 0x02
#define COMM_OPT_3 0x04
/* These three variables control behaviour if non-zero */
static int only_file_1;
static int only_file_2;
static int both;
/* writeline outputs the input given, appropriately aligned according to class */
static void writeline(char *line, int class)
{
if (class == 0) {
if (!only_file_1)
return;
} else if (class == 1) {
if (!only_file_2)
return;
if (only_file_1)
putchar('\t');
}
else /*if (class == 2)*/ {
if (!both)
return;
if (only_file_1)
putchar('\t');
if (only_file_2)
putchar('\t');
}
fputs(line, stdout);
}
/* This is the real core of the program - lines are compared here */
static void cmp_files(char **infiles)
{
#define LINE_LEN 100
#define BB_EOF_0 0x1
#define BB_EOF_1 0x2
char thisline[2][LINE_LEN];
FILE *streams[2];
int i;
for (i = 0; i < 2; ++i) {
streams[i] = ((infiles[i][0] == '=' && infiles[i][1]) ? stdin : xfopen(infiles[i], "r"));
fgets(thisline[i], LINE_LEN, streams[i]);
}
while (*thisline[0] || *thisline[1]) {
int order = 0;
i = 0;
if (feof(streams[0])) i |= BB_EOF_0;
if (feof(streams[1])) i |= BB_EOF_1;
if (!*thisline[0])
order = 1;
else if (!*thisline[1])
order = -1;
else {
int tl0_len, tl1_len;
tl0_len = strlen(thisline[0]);
tl1_len = strlen(thisline[1]);
order = memcmp(thisline[0], thisline[1], tl0_len < tl1_len ? tl0_len : tl1_len);
if (!order)
order = tl0_len < tl1_len ? -1 : tl0_len != tl1_len;
}
if (order == 0 && !i)
writeline(thisline[1], 2);
else if (order > 0 && !(i & BB_EOF_1))
writeline(thisline[1], 1);
else if (order < 0 && !(i & BB_EOF_0))
writeline(thisline[0], 0);
if (i & BB_EOF_0 & BB_EOF_1) {
break;
} else if (i) {
i = (i & BB_EOF_0 ? 1 : 0);
while (!feof(streams[i])) {
if ((order < 0 && i) || (order > 0 && !i))
writeline(thisline[i], i);
fgets(thisline[i], LINE_LEN, streams[i]);
}
break;
} else {
if (order >= 0)
fgets(thisline[1], LINE_LEN, streams[1]);
if (order <= 0)
fgets(thisline[0], LINE_LEN, streams[0]);
}
}
fclose(streams[0]);
fclose(streams[1]);
}
int comm_main(int argc, char **argv)
{
unsigned long flags;
flags = bb_getopt_ulflags(argc, argv, "123");
if (optind + 2 != argc)
bb_show_usage();
only_file_1 = !(flags & COMM_OPT_1);
only_file_2 = !(flags & COMM_OPT_2);
both = !(flags & COMM_OPT_3);
cmp_files(argv + optind);
exit(EXIT_SUCCESS);
}