Add megabytes display format to free

[Matthew Hiles]

Hello Busybox mailing list:

I just joined the mailing list because I'm interested in helping out
with busybox.

I've been reading TODOs and the bug tracker to find out what I can do.
I'm not sure how opposed everyone is to feature creep, as I'm sure
it's an issue, but one thing that always bothered me when using a
busybox system was the lack of the -m option for free.

I also checked out the TODO in free about fixing the integer overflow
on systems with >4gb of RAM. I tried busybox's free command on a 6 GB
system and it did not overflow--it showed exactly the same output as
the in-distro free command. Does anyone know what's up with that?

The following patch allows free to display in megabytes.


--- procps/free.c	2008-11-18 09:08:29.000000000 -0500
+++ procps/free.c	2008-11-18 08:06:16.000000000 -0500
@@ -46,8 +46,21 @@
 		info.bufferram*=info.mem_unit;
 	}

-	if (argc > 1 && *argv[1] == '-')
-		bb_show_usage();
+	if ( argc > 1 )
+	{
+		if ( argv[1][1] == 'm' ) /* I see no point invoking getopt */
+		{                        /* or even strcmp for one option */
+			/* give output in megabytes */
+			info.totalram /= 1024;
+			info.freeram /= 1024;
+			info.sharedram /= 1024;
+			info.bufferram /= 1024;
+#ifndef __uClinux__
+			info.totalswap /= 1024;
+			info.freeswap /= 1024;
+#endif
+		} else bb_show_usage();
+	}

 	printf("%6s%13s%13s%13s%13s%13s\n", "", "total", "used", "free",
 			"shared", "buffers");