libgrapheme

commit 65785f699be45dd77bdcbfc1d3aded39151f3205
parent b13acfd6cd5114fcddbffaf9855664a95f966403
Author: Laslo Hunhold <dev@frign.de>
Date:   Sat, 24 Sep 2022 11:45:20 +0200

Refactor character-functions with Herodotus

This also unifies the code and drops a lot of complicated state
handling.

Signed-off-by: Laslo Hunhold <dev@frign.de>

Diffstat:
M
src/character.c
 | 
60
+++++++++++++++++++-----------------------------------------
M
src/util.c
 | 
6
+++++-

2 files changed, 24 insertions(+), 42 deletions(-)
diff --git a/src/character.c b/src/character.c
@@ -175,61 +175,39 @@ grapheme_is_character_break(uint_least32_t cp0, uint_least32_t cp1, GRAPHEME_STA
 	return !notbreak;
 }
 
-size_t
-grapheme_next_character_break(const uint_least32_t *str, size_t len)
+static size_t
+next_character_break(HERODOTUS_READER *r)
 {
 	GRAPHEME_STATE state = { 0 };
-	size_t off;
-
-	if (str == NULL || len == 0) {
-		return 0;
-	}
+	uint_least32_t cp0 = 0, cp1 = 0;
 
-	for (off = 1; off < len; off++) {
-		if (grapheme_is_character_break(str[off - 1], str[off], &state)) {
+	for (herodotus_read_codepoint(r, true, &cp0);
+	     herodotus_read_codepoint(r, false, &cp1) == HERODOTUS_STATUS_SUCCESS;
+	     herodotus_read_codepoint(r, true, &cp0)) {
+		if (grapheme_is_character_break(cp0, cp1, &state)) {
 			break;
 		}
 	}
 
-	return off;
+	return herodotus_reader_number_read(r);
 }
 
 size_t
-grapheme_next_character_break_utf8(const char *str, size_t len)
+grapheme_next_character_break(const uint_least32_t *str, size_t len)
 {
-	GRAPHEME_STATE state = { 0 };
-	uint_least32_t cp0 = 0, cp1 = 0;
-	size_t off, ret;
-
-	if (str == NULL || len == 0) {
-		return 0;
-	}
+	HERODOTUS_READER r;
 
-	for (off = 0; (len == SIZE_MAX) || off < len; off += ret) {
-		cp0 = cp1;
-		ret = grapheme_decode_utf8(str + off, (len == SIZE_MAX) ?
-		                           SIZE_MAX : len - off, &cp1);
+	herodotus_reader_init(&r, HERODOTUS_TYPE_CODEPOINT, str, len);
 
-		if (len != SIZE_MAX && ret > (len - off)) {
-			/* string ended abruptly, simply accept cropping */
-			ret = len - off;
-		}
+	return next_character_break(&r);
+}
 
-		if (len == SIZE_MAX && cp1 == 0) {
-			/* we hit a NUL-byte and are done */
-			break;
-		}
+size_t
+grapheme_next_character_break_utf8(const char *str, size_t len)
+{
+	HERODOTUS_READER r;
 
-		if (off == 0) {
-			/*
-			 * we skip the first round, as we need both
-			 * cp0 and cp1 to be initialized
-			 */
-			continue;
-		} else if (grapheme_is_character_break(cp0, cp1, &state)) {
-			break;
-		}
-	}
+	herodotus_reader_init(&r, HERODOTUS_TYPE_UTF8, str, len);
 
-	return off;
+	return next_character_break(&r);
 }
diff --git a/src/util.c b/src/util.c
@@ -111,7 +111,11 @@ herodotus_read_codepoint(HERODOTUS_READER *r, bool advance, uint_least32_t *cp)
 	}
 
 	if (r->type == HERODOTUS_TYPE_CODEPOINT) {
-		*cp = ((const uint_least32_t *)(r->src))[r->off++];
+		*cp = ((const uint_least32_t *)(r->src))[r->off];
+
+		if (advance) {
+			r->off++;
+		}
 	} else { /* r->type == HERODOTUS_TYPE_UTF8 */
 		ret = grapheme_decode_utf8((const char *)r->src + r->off,
 		                           MIN(r->srclen, r->soft_limit[0]) -