Improve UTF-8 handling.

This should allow case-insensitive matching for non-Latin characters,
and fix matching for characters with diacritics.

1 files changed, 92 insertions, 0 deletions

diff --git a/src/utf8.c b/src/utf8.c
new file mode 100644
index 0000000..7ed6046
--- /dev/null
+++ b/src/utf8.c
@@ -0,0 +1,92 @@
+#include <string.h>
+
+#include "utf8.h"
+
+uint32_t utf8_isupper(uint32_t c)
+{
+	return g_unichar_isupper(c);
+}
+
+uint32_t utf8_islower(uint32_t c)
+{
+	return g_unichar_islower(c);
+}
+
+uint32_t utf8_isalnum(uint32_t c)
+{
+	return g_unichar_isalnum(c);
+}
+
+uint32_t utf8_toupper(uint32_t c)
+{
+	return g_unichar_toupper(c);
+}
+
+uint32_t utf8_tolower(uint32_t c)
+{
+	return g_unichar_tolower(c);
+}
+
+uint32_t utf8_get_char(const char *s)
+{
+	return g_utf8_get_char(s);
+}
+
+char *utf8_next_char(const char *s)
+{
+	return g_utf8_next_char(s);
+}
+
+char *utf8_prev_char(const char *s)
+{
+	return g_utf8_prev_char(s);
+}
+
+char *utf8_strchr(const char *s, uint32_t c)
+{
+	return g_utf8_strchr(s, -1, c);
+}
+
+char *utf8_strcasechr(const char *s, uint32_t c)
+{
+	c = g_unichar_tolower(c);
+
+	const char *p = s;
+	while (*p != '\0' && g_unichar_tolower(g_utf8_get_char(p)) != c) {
+		p = g_utf8_next_char(p);
+	}
+	if (*p == '\0') {
+		return NULL;
+	}
+	return (char *)p;
+}
+
+size_t utf8_strlen(const char *s)
+{
+	return g_utf8_strlen(s, -1);
+}
+
+char *utf8_strcasestr(const char * restrict haystack, const char * restrict needle)
+{
+	char *h = g_utf8_casefold(haystack, -1);
+	char *n = g_utf8_casefold(needle, -1);
+
+	char *cmp = strstr(h, n);
+	char *ret;
+
+	if (cmp == NULL) {
+		ret = NULL;
+	} else {
+		ret = (char *)haystack + (cmp - h);
+	}
+
+	free(h);
+	free(n);
+
+	return ret;
+}
+
+char *utf8_normalize(const char *s)
+{
+	return g_utf8_normalize(s, -1, G_NORMALIZE_DEFAULT);
+}