improve orca target

base/runtime/os_specific_orca.odin

@@ -0,0 +1,43 @@
+//+build orca
+//+private
+package runtime
+
+import "base:intrinsics"
+
+// Constants allowing to specify the level of logging verbosity.
+log_level :: enum u32 {
+	// Only errors are logged.
+	ERROR = 0,
+	// Only warnings and errors are logged.
+	WARNING = 1,
+	// All messages are logged.
+	INFO = 2,
+	COUNT = 3,
+}
+
+@(default_calling_convention="c", link_prefix="oc_")
+foreign {
+	abort_ext   :: proc(file: cstring, function: cstring, line: i32, fmt: cstring, #c_vararg args: ..any) -> ! ---
+	assert_fail :: proc(file: cstring, function: cstring, line: i32, src: cstring, fmt: cstring, #c_vararg args: ..any) -> ! ---
+	log_ext     :: proc(level: log_level, function: cstring, file: cstring, line: i32, fmt: cstring, #c_vararg args: ..any) ---
+}
+
+// NOTE: This is all pretty gross, don't look.
+
+// WASM is single threaded so this should be fine.
+orca_stderr_buffer:     [4096]byte
+orca_stderr_buffer_idx: int
+
+_stderr_write :: proc "contextless" (data: []byte) -> (int, _OS_Errno) {
+	for b in data {
+		orca_stderr_buffer[orca_stderr_buffer_idx] = b
+		orca_stderr_buffer_idx += 1
+
+		if b == '\n' || orca_stderr_buffer_idx == len(orca_stderr_buffer)-1 {
+			log_ext(.ERROR, "", "", 0, cstring(raw_data(orca_stderr_buffer[:orca_stderr_buffer_idx])))
+			orca_stderr_buffer_idx = 0
+		}
+	}
+
+	return len(data), 0
+}