Teach Git how to parse standard power of 2 suffixes.

Sometimes its necessary to supply a value as a power of two in a
configuration parameter.  In this case the user may want to use the
standard suffixes such as K, M, or G to indicate that the numerical
value should be multiplied by a constant base before being used.

Shell scripts/etc. can also benefit from this automatic option
parsing with `git repo-config --int`.

[jc: with a couple of test and a slight input tightening]
Signed-off-by: NShawn O. Pearce <spearce@spearce.org>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

Documentation/git-repo-config.txt

@@ -87,7 +87,10 @@ OPTIONS
 	git-repo-config will ensure that the output is "true" or "false"
 
 --int::
-	git-repo-config will ensure that the output is a simple decimal number
+	git-repo-config will ensure that the output is a simple
+	decimal number.  An optional value suffix of 'k', 'm', or 'g'
+	in the config file will cause the value to be multiplied
+	by 1024, 1048576, or 1073741824 prior to output.
 
 
 ENVIRONMENT

config.c

@@ -238,6 +238,12 @@ int git_config_int(const char *name, const char *value)
 		int val = strtol(value, &end, 0);
 		if (!*end)
 			return val;
+		if (!strcasecmp(end, "k"))
+			return val * 1024;
+		if (!strcasecmp(end, "m"))
+			return val * 1024 * 1024;
+		if (!strcasecmp(end, "g"))
+			return val * 1024 * 1024 * 1024;
 	}
 	die("bad config value for '%s' in %s", name, config_file_name);
 }

t/t1300-repo-config.sh

@@ -391,5 +391,15 @@ EOF
 
 test_expect_success "rename succeeded" "diff -u expect .git/config"
 
+test_expect_success numbers '
+
+	git-repo-config kilo.gram 1k &&
+	git-repo-config mega.ton 1m &&
+	k=$(git-repo-config --int --get kilo.gram) &&
+	test z1024 = "z$k" &&
+	m=$(git-repo-config --int --get mega.ton) &&
+	test z1048576 = "z$m"
+'
+
 test_done