move string32.c into util.c

1 files changed, 181 insertions, 5 deletions

diff --git a/util.c b/util.c
index f8bdab5..6751a72 100644
--- a/util.c
+++ b/util.c
@@ -14,16 +14,28 @@
 // it is unusual to have a string that long.
 #define STRLEN_SAFE_MAX (UINT_MAX >> 2)
 
-bool is_word(char32_t c) {
+bool is32_word(char32_t c) {
 	return c > WCHAR_MAX || c == '_' || iswalnum((wint_t)c);
 }
 
-bool is_digit(char32_t c) {
-	return c < WCHAR_MAX && iswdigit((wint_t)c);
+bool is32_space(char32_t c) {
+	return c <= WINT_MAX && iswspace((wint_t)c);
 }
 
-bool is_space(char32_t c) {
-	return c < WCHAR_MAX && iswspace((wint_t)c);
+bool is32_alpha(char32_t c) {
+	return c <= WINT_MAX && iswalpha((wint_t)c);
+}
+
+bool is32_alnum(char32_t c) {
+	return c <= WINT_MAX && iswalnum((wint_t)c);
+}
+
+bool is32_digit(char32_t c) {
+	return c <= WINT_MAX && iswdigit((wint_t)c);
+}
+
+bool is32_graph(char32_t c) {
+	return c <= WINT_MAX && iswgraph((wint_t)c);
 }
 
 bool is_a_tty(FILE *out) {
@@ -1250,3 +1262,167 @@ double timespec_to_seconds(struct timespec ts) {
 	return (double)ts.tv_sec
 		+ (double)ts.tv_nsec * 1e-9;
 }
+
+
+String32 str32(char32_t *str, size_t len) {
+	String32 s = {str, len};
+	return s;
+}
+
+String32 str32_substr(String32 s, size_t from, size_t len) {
+	return str32(s.str + from, len);
+}
+
+// frees string and sets it to ""
+void str32_free(String32 *s) {
+	free(s->str);
+	s->str = NULL;
+	s->len = 0;
+}
+
+// the string returned should be str32_free'd.
+// this will return an empty string if the allocation failed or the string is invalid UTF-8
+String32 str32_from_utf8(char const *utf8) {
+	String32 string = {NULL, 0};
+	size_t len = strlen(utf8);
+	if (len) {
+		// the wide string uses at most as many "characters" (elements?) as the UTF-8 string
+		char32_t *widestr = calloc(len, sizeof *widestr);
+		if (widestr) {
+			char32_t *wide_p = widestr;
+			char const *utf8_p = utf8;
+			char const *utf8_end = utf8_p + len;
+			while (utf8_p < utf8_end) {
+				char32_t c = 0;
+				size_t n = unicode_utf8_to_utf32(&c, utf8_p, (size_t)(utf8_end - utf8_p));
+				if (n == 0 // null character. this shouldn't happen.
+					|| n >= (size_t)(-2) // invalid UTF-8
+					) {
+					free(widestr);
+					widestr = wide_p = NULL;
+					break;
+				} else {
+					// n bytes consumed
+					*wide_p++ = c;
+					utf8_p += n;
+				}
+			}
+			string.str = widestr;
+			string.len = (size_t)(wide_p - widestr);
+		}
+	}
+	return string;
+}
+
+// returns a null-terminated UTF-8 string
+// the string returned should be free'd
+// this will return NULL on failure
+char *str32_to_utf8_cstr(String32 s) {
+	char *utf8 = calloc(4 * s.len + 1, 1); // each codepoint takes up at most 4 bytes in UTF-8, + we need a terminating null byte
+	if (utf8) {
+		char *p = utf8;
+		for (size_t i = 0; i < s.len; ++i) {
+			size_t bytes = unicode_utf32_to_utf8(p, s.str[i]);
+			if (bytes == (size_t)-1) {
+				// invalid UTF-32 code point
+				free(utf8);
+				return NULL;
+			} else {
+				p += bytes;
+			}
+		}
+		*p = '\0';
+	}
+	return utf8;
+}
+
+// compare s to the ASCII string `ascii`
+int str32_cmp_ascii(String32 s, char const *ascii) {
+	for (size_t i = 0; i < s.len; ++i) {
+		assert((char32_t)ascii[i] < 128);
+		if ((char32_t)ascii[i] == '\0')
+			return -1; // ascii is a prefix of s
+		if (s.str[i] > (char32_t)ascii[i])
+			return +1;
+		if (s.str[i] < (char32_t)ascii[i])
+			return -1;
+	}
+	if (ascii[s.len]) {
+		// s is a prefix of ascii
+		return +1;
+	}
+	return 0;
+}
+
+// check if s starts with the ASCII string `ascii`
+bool str32_has_ascii_prefix(String32 s, char const *ascii) {
+	for (size_t i = 0; i < s.len; ++i) {
+		assert((char32_t)ascii[i] < 128);
+		if ((char32_t)ascii[i] == '\0')
+			return true; // ascii is a prefix of s
+		if (s.str[i] > (char32_t)ascii[i])
+			return false;
+		if (s.str[i] < (char32_t)ascii[i])
+			return false;
+	}
+	if (ascii[s.len]) {
+		// s is a prefix of ascii
+		return false;
+	}
+	// s is the same as ascii
+	return true;
+}
+
+// returns the index of the given character in the string, or the length of the string if it's not found.
+size_t str32chr(String32 s, char32_t c) {
+	for (size_t i = 0; i < s.len; ++i) {
+		if (s.str[i] == c)
+			return i;
+	}
+	return s.len;
+}
+
+// returns number of instances of c in s
+size_t str32_count_char(String32 s, char32_t c) {
+	size_t total = 0;
+	for (size_t i = 0; i < s.len; ++i) {
+		total += s.str[i] == c;
+	}
+	return total;
+}
+
+// returns number of characters deleted from s
+size_t str32_remove_all_instances_of_char(String32 *s, char32_t c) {
+	char32_t *str = s->str;
+	size_t ndeleted = 0;
+	size_t len = s->len;
+	size_t out = 0;
+	for (size_t in = 0; in < len; ++in) {
+		if (str[in] == c) {
+			++ndeleted;
+		} else {
+			str[out++] = str[in];
+		}
+	}
+	s->len = out;
+	return ndeleted;
+}
+
+// returns the length of the longest prefix of `s` containing only
+// ASCII characters in the C-string `charset`.
+size_t str32_ascii_spn(String32 s, char const *charset) {
+	for (u32 i = 0; i < s.len; ++i) {
+		if (s.str[i] >= 128)
+			return i; // non-ASCII character in s, so that can't be in charset.
+		bool found = false;
+		for (char const *p = charset; *p; ++p) {
+			assert((char32_t)*p < 128);
+			if ((char32_t)*p == s.str[i]) {
+				found = true;
+				break;
+			}
+		}
+		if (!found) return i;
+	}
+	return s.len;
+}