internal/rosa/package: migrate many libraries

This also adds more string helpers.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/rosa/package/libcap.az

@@ -0,0 +1,44 @@
+package libcap {
+	description = "a library for getting and setting POSIX.1e draft 15 capabilities";
+	website = "https://sites.google.com/site/fullycapable";
+	anitya = 1569;
+
+	version* = "2.78";
+	source = remoteTar {
+		url = "https://git.kernel.org/pub/scm/libs/libcap/libcap.git/"+
+			"snapshot/libcap-"+version+".tar.gz";
+		checksum = "wFdUkBhFMD9InPnrBZyegWrlPSAg_9JiTBC-eSFyWWlmbzL2qjh2mKxr9Kx2a8ut";
+		compress = gzip;
+	};
+
+	// uses source tree as scratch space
+	writable = true;
+	chmod = true;
+
+	env = [
+		"prefix=/system",
+		"lib=lib",
+	];
+
+	early = "\nln -s ../system/bin/bash /bin/\n";
+
+	exec = make {
+		skipConfigure = true;
+		inPlace = true;
+
+		make = [
+			"CC=cc",
+			"all",
+		];
+
+		check = [
+			"CC=cc",
+			"test",
+		];
+	};
+
+	inputs = [
+		bash,
+		diffutils,
+	];
+}