3 files changed, 61 insertions, 34 deletions

diff --git a/lib/unicode/string/u8casefold.c b/lib/unicode/string/u8casefold.c
index 2ab7c7c..aba08f3 100644
--- a/lib/unicode/string/u8casefold.c
+++ b/lib/unicode/string/u8casefold.c
@@ -1,24 +1,32 @@
+#include <errno.h>
+#include <stdckdint.h>
+
 #include "mbstring.h"
 #include "unicode/prop.h"
 #include "unicode/string.h"
 
-size_t
-u8casefold(char8_t *restrict dst, size_t dstn, struct u8view sv,
-           enum caseflags flags)
+char8_t *
+u8casefold(size_t *dstn, struct u8view sv, enum caseflags flags, alloc_fn alloc,
+           void *alloc_ctx)
 {
+	size_t bufsz;
+	if (ckd_mul(&bufsz, sv.len, (size_t)U8CASEFOLD_SCALE)) {
+		errno = EOVERFLOW;
+		return nullptr;
+	}
+
+	char8_t *dst = alloc(alloc_ctx, nullptr, 0, bufsz, alignof(char8_t));
+	if (dst == nullptr)
+		return nullptr;
+
 	rune ch;
 	size_t n = 0;
-
 	while (u8next(&ch, &sv)) {
 		struct rview rv = uprop_get_cf(ch, flags & CF_LANG_AZ);
-		for (size_t i = 0; i < rv.len; i++) {
-			if (n >= dstn) {
-				char8_t buf[U8_LEN_MAX];
-				n += rtou8(buf, sizeof(buf), rv.p[i]);
-			} else
-				n += rtou8(dst + n, dstn - n, rv.p[i]);
-		}
+		for (size_t i = 0; i < rv.len; i++)
+			n += rtou8(dst + n, bufsz - n, rv.p[i]);
 	}
 
-	return n;
+	*dstn = n;
+	return alloc(alloc_ctx, dst, bufsz, n, alignof(char8_t));
 }
diff --git a/lib/unicode/string/u8lower.c b/lib/unicode/string/u8lower.c
index 907077b..47c32f5 100644
--- a/lib/unicode/string/u8lower.c
+++ b/lib/unicode/string/u8lower.c
@@ -1,3 +1,6 @@
+#include <errno.h>
+#include <stdckdint.h>
+
 #include "_attrs.h"
 #include "mbstring.h"
 #include "unicode/prop.h"
@@ -12,9 +15,9 @@ uprop_ccc_0_or_230(rune ch)
 	return x == 0 || x == 230;
 }
 
-size_t
-u8lower(char8_t *restrict dst, size_t dstn, struct u8view sv,
-        enum caseflags flags)
+char8_t *
+u8lower(size_t *dstn, struct u8view sv, enum caseflags flags, alloc_fn alloc,
+        void *alloc_ctx)
 {
 	struct lcctx ctx = {
 		.az_or_tr = flags & CF_LANG_AZ,
@@ -32,6 +35,17 @@ u8lower(char8_t *restrict dst, size_t dstn, struct u8view sv,
 
 	n = before_dot_cnt = more_above_cnt = 0;
 
+	size_t bufsz;
+	/* TODO: Also use U8LOWER_SCALE */
+	if (ckd_mul(&bufsz, sv.len, (size_t)U8LOWER_SCALE_LT)) {
+		errno = EOVERFLOW;
+		return nullptr;
+	}
+
+	char8_t *dst = alloc(alloc_ctx, nullptr, 0, bufsz, alignof(char8_t));
+	if (dst == nullptr)
+		return nullptr;
+
 	while (u8next(&ch, &sv)) {
 		rune next = 0;
 		if (sv.len > 0)
@@ -76,13 +90,8 @@ u8lower(char8_t *restrict dst, size_t dstn, struct u8view sv,
 		ctx.final_sigma = final_sigma.before && final_sigma.after == 0;
 
 		struct rview rv = uprop_get_lc(ch, ctx);
-		for (size_t i = 0; i < rv.len; i++) {
-			if (n >= dstn) {
-				char8_t buf[U8_LEN_MAX];
-				n += rtou8(buf, sizeof(buf), rv.p[i]);
-			} else
-				n += rtou8(dst + n, dstn - n, rv.p[i]);
-		}
+		for (size_t i = 0; i < rv.len; i++)
+			n += rtou8(dst + n, bufsz - n, rv.p[i]);
 
 		ctx.after_I = (ch == 'I') || (ctx.after_I && !uprop_ccc_0_or_230(ch));
 		if (uprop_is_cased(ch))
@@ -91,5 +100,6 @@ u8lower(char8_t *restrict dst, size_t dstn, struct u8view sv,
 			final_sigma.before = false;
 	}
 
-	return n;
+	*dstn = n;
+	return alloc(alloc_ctx, dst, bufsz, n, alignof(char8_t));
 }
diff --git a/lib/unicode/string/u8title.c b/lib/unicode/string/u8title.c
index f4d9b7e..1adf110 100644
--- a/lib/unicode/string/u8title.c
+++ b/lib/unicode/string/u8title.c
@@ -1,3 +1,6 @@
+#include <errno.h>
+#include <stdckdint.h>
+
 #include "_attrs.h"
 #include "mbstring.h"
 #include "unicode/prop.h"
@@ -13,9 +16,9 @@ uprop_ccc_0_or_230(rune ch)
 	return x == 0 || x == 230;
 }
 
-size_t
-u8title(char8_t *restrict dst, size_t dstn, struct u8view sv,
-        enum caseflags flags)
+char8_t *
+u8title(size_t *dstn, struct u8view sv, enum caseflags flags, alloc_fn alloc,
+        void *alloc_ctx)
 {
 	struct tcctx ctx_t;
 	struct lcctx ctx_l;
@@ -39,6 +42,16 @@ u8title(char8_t *restrict dst, size_t dstn, struct u8view sv,
 
 	n = before_dot_cnt = more_above_cnt = 0;
 
+	size_t bufsz;
+	if (ckd_mul(&bufsz, sv.len, (size_t)U8TITLE_SCALE)) {
+		errno = EOVERFLOW;
+		return nullptr;
+	}
+
+	char8_t *dst = alloc(alloc_ctx, nullptr, 0, bufsz, alignof(char8_t));
+	if (dst == nullptr)
+		return nullptr;
+
 	while (u8next(&ch, &sv)) {
 		if (sv.p > word.p + word.len) {
 			u8wnext(&word, &wcpy);
@@ -102,13 +115,8 @@ u8title(char8_t *restrict dst, size_t dstn, struct u8view sv,
 			}
 		}
 
-		for (size_t i = 0; i < rv.len; i++) {
-			if (n >= dstn) {
-				char8_t buf[U8_LEN_MAX];
-				n += rtou8(buf, sizeof(buf), rv.p[i]);
-			} else
-				n += rtou8(dst + n, dstn - n, rv.p[i]);
-		}
+		for (size_t i = 0; i < rv.len; i++)
+			n += rtou8(dst + n, bufsz - n, rv.p[i]);
 
 		ctx_l.after_I =
 			(ch == 'I') || (ctx_l.after_I && !uprop_ccc_0_or_230(ch));
@@ -123,5 +131,6 @@ u8title(char8_t *restrict dst, size_t dstn, struct u8view sv,
 			ctx_t.after_soft_dotted = false;
 	}
 
-	return n;
+	*dstn = n;
+	return alloc(alloc_ctx, dst, bufsz, n, alignof(char8_t));
 }