hare

commit a67d398a910a510700d21569dce2c7a81ae85243
parent 6f9b6114b7f61041823924dfcfea6fa05907b985
Author: Sebastian <sebastian@sebsite.pw>
Date:   Tue, 18 Jul 2023 18:56:03 -0400

types::c: add nulstr

So C strings can be used without allocating them:

	use types::c;

	@symbol("puts") fn puts(s: *const char) int;

	export fn main() void = {
		puts(c::nulstr("hello world!\0"));
	};

Signed-off-by: Sebastian <sebastian@sebsite.pw>

Diffstat:
M
types/c/+test.ha
 | 
2
++
M
types/c/strings.ha
 | 
9
+++++++++

2 files changed, 11 insertions(+), 0 deletions(-)
diff --git a/types/c/+test.ha b/types/c/+test.ha
@@ -21,4 +21,6 @@
 	let s = fromstr("hello!");
 	defer free(s);
 	assert(tostr(s)! == "hello!");
+	let s = nulstr("hello!\0");
+	assert(tostr(s)! == "hello!");
 };
diff --git a/types/c/strings.ha b/types/c/strings.ha
@@ -60,3 +60,12 @@ export fn fromstr_buf(s: const str, sl: []char) *char = {
 
 	return (*(&sl: *types::slice)).data: *char;
 };
+
+// Converts a NUL-terminated Hare string to a C string. Aborts if the input
+// string isn't NUL-terminated. The result is borrowed from the input.
+export fn nulstr(s: const str) *const char = {
+	let s = &s: *types::string;
+	let data = s.data as *[*]u8;
+	assert(data[s.length - 1] == '\0', "types::c::nulstr input must be NUL-terminated");
+	return s.data: *const char;
+};