Attempted rewrite of _display_get_fmt()`, it currently doesn"t work. To compile using the old functional but (probably) unsafe function, pass `-D_DEBUG_USE_UNSAFE_DISPLAY_FMT_ARGS` in `CFLAGS`.

TODO: Find out why _display_get_fmt_n()` is so broken...

TODO: Make `_display_get_fmt()` a function alias instead of macro definition

Fixed `deprecated` macro conflicts with attribute usage. (renamed to `_deprecated`)

Fortune for naka's current commit: Half blessing − 半吉

include/macros.h

@@ -18,11 +18,13 @@
 
 #define _cold __attribute__((cold))
 #define _hot __attribute__((hot))
+#define _dead __attribute__((unused))
 
 #ifndef __cplusplus
 #define noreturn __attribute__((noreturn))
-#define deprecated __attribute__((deprecated))
-#define deprecated_message(str) __attribute__((deprecated(str))) 
+#define _deprecated __attribute__((deprecated))
+#define deprecated_message(str) __attribute__((deprecated(str)))
+#define _deprecated_msg(str) deprecated_message(str)
 #endif
 
 #define noinline __attribute__((noinline))

src/display.c

@@ -53,8 +53,59 @@ static inline usize strncat_n(char*pOUT dest, const char* restrict src, usize n)
 	return strncpy_n(dest+dl, src, n);
 }
 
-//TODO: This works, but seems inherantly unsafe. Rewrite to use the above `strn*_n()` functions for better length tracking.
-static usize _display_get_fmt(dispflags_t flags, bool matched, usize _len, char str[pOUT _len])
+//TODO: This isn't working at all...
+#ifdef _DEBUG_USE_UNSAFE_DISPLAY_FMT_ARGS
+_dead
+#endif
+static usize _display_get_fmt_n(dispflags_t flags, bool matched, usize _n, char str[pOUT _n])
+{
+	register usize n = _n, fw=0;
+	const char* fmts[] = { 
+				DFLAGSET(flags, FAILURES) 
+				? "failure: " 
+				: "",  
+
+				"match: ", 
+				"%lu: ", 
+				SLICE_FORMAT, 
+				" (len %lu)", 
+				(const char*)NULL,
+	};
+	usize   w = s_strncpy_n(str, n, fmts[!!matched], n); // SAFETY: Will never read past `fmts[x]` nul-terminator, so setting n as both dest and src length here is safe.
+//TODO: Fix this... It isn't working...
+#define ADDSTR(s) do { \
+		debug_assert((s)); \
+		w = MINx(s_strncat_n(str, n, (s), n), n); \
+		/* Remove written from `n` */ \
+		n -= w; \
+		/* Check if we have written into the limit (if so, w will be equal to n above, since w is high-bounded to n by `MINx()` above. So if n is 0, we have hit the limit. */ \
+		ifU(!n) { \
+			/*XXX: Should this be `str[w-1]?` If this assert fails then yes it should. */ \
+			debug_assert(w < _n); \
+			str[w] = 0; \
+			return fw + w; \
+		} \
+		/* Increase `str` pointer by written */ \
+		str += w; \
+		/* Increase return value by written. */ \
+		fw += w; \
+	} while(0)
+
+	if(DFLAGSET(flags, NUMBER)) ADDSTR(fmts[2]);
+	if(DFLAGSET(flags, SLICE)) ADDSTR(fmts[3]);
+	if(DFLAGSET(flags, LENGTH)) ADDSTR(fmts[4]);
+	ADDSTR("\n");
+	TRACE("Output string written: %lu, (rlen %lu)", fw, n);
+#undef ADDSTR
+	return fw;
+}
+
+
+//XXX: This works, but seems inherantly unsafe. Rewrite to use the above `strn*_n()` functions for better length tracking.
+#ifndef _DEBUG_USE_UNSAFE_DISPLAY_FMT_ARGS
+_dead deprecated_message("this is unsafe, use `_display_get_fmt_n`") 
+#endif
+static usize _display_get_fmt0(dispflags_t flags, bool matched, usize _len, char str[pOUT _len])
 {
 	register usize len = _len;
 	static const char* fmts[] = { "match: ", "%lu: ", SLICE_FORMAT, " (len %lu)", "failure: ", (const char*)NULL };
@@ -72,6 +123,12 @@ static usize _display_get_fmt(dispflags_t flags, bool matched, usize _len, char
 #undef ADDSTR
 }
 
+#ifdef _DEBUG_USE_UNSAFE_DISPLAY_FMT_ARGS
+#define _display_get_fmt(...) _display_get_fmt0(__VA_ARGS__)
+#else
+#define _display_get_fmt(...) _display_get_fmt_n(__VA_ARGS__)
+#endif
+
 static void _display_normal(FILE* output, dispin_t*pIN input, dispflags_t flags)
 {
 	bool matched = input->matched;
@@ -91,9 +148,14 @@ static void _display_normal(FILE* output, dispin_t*pIN input, dispflags_t flags)
 #endif
 	INFO("Mapped region slice for %lu, pre-transform (at %p): " SLICE_FORMAT ", len: %lu", i+1, base, SLICE_FORMAT_ARGS(&cslice), cslice.len);
 
-	//Honour `flags`
+	// --- get format string from `flags` ---
 	char fmt[200]; //TODO: Find the realistic max for this.
-	fmt[_display_get_fmt(flags, matched, 100, fmt)] = 0;
+	usize fmtw = _display_get_fmt(flags, matched, sizeof(fmt)-1, fmt);
+	assert(fmtw+1 < sizeof(fmt));
+	fmt[fmtw+1] = 0;
+	// ---
+	TRACE("Format string get: `%s' (%lu)", fmt, fmtw);
+
 	fprintf(output, fmt, i+1, pos.start, pos.end, pos.end-pos.start);
 }