String support

src/string.cpp

@@ -0,0 +1,262 @@
+
+// NOTE(bill): Used for UTF-8 strings
+typedef struct String {
+	u8 *text;
+	isize len;
+} String;
+// NOTE(bill): used for printf style arguments
+#define LIT(x) (x).len, (x).text
+
+
+
+
+gb_inline String make_string(u8 *text, isize len) {
+	String s;
+	s.text = text;
+	if (len < 0)
+		len = gb_strlen(cast(char *)text);
+	s.len = len;
+	return s;
+}
+
+gb_inline String make_string(char *text) {
+	return make_string(cast(u8 *)cast(void *)text, gb_strlen(text));
+}
+
+gb_inline b32 are_strings_equal(String a, String b) {
+	if (a.len == b.len) {
+		return gb_memcompare(a.text, b.text, a.len) == 0;
+	}
+	return false;
+}
+
+gb_inline b32 are_strings_equal_ignore_case(String a, String b) {
+	if (a.len == b.len) {
+		for (isize i = 0; i < a.len; i++) {
+			char x = cast(char)a.text[i];
+			char y = cast(char)b.text[i];
+			if (gb_char_to_lower(x) != gb_char_to_lower(y))
+				return false;
+		}
+		return true;
+	}
+	return false;
+}
+
+
+gb_inline isize string_extension_position(String str) {
+	isize dot_pos = -1;
+	isize i = str.len;
+	b32 seen_dot = false;
+	while (i --> 0) {
+		if (str.text[i] == GB_PATH_SEPARATOR)
+			break;
+		if (str.text[i] == '.') {
+			dot_pos = i;
+			break;
+		}
+	}
+
+	return dot_pos;
+}
+
+gb_inline b32 string_has_extension(String str, String ext) {
+	if (str.len > ext.len+1) {
+		u8 *s = str.text+str.len - ext.len-1;
+		if (s[0] == '.') {
+			s++;
+			return gb_memcompare(s, ext.text, ext.len) == 0;
+		}
+		return false;
+	}
+	return false;
+}
+
+b32 string_contains_char(String s, u8 c) {
+	for (isize i = 0; i < s.len; i++) {
+		if (s.text[i] == c)
+			return true;
+	}
+	return false;
+}
+
+b32 unquote_char(String s, u8 quote, Rune *rune, b32 *multi, String *tail_string) {
+	if (s.text[0] == quote &&
+	    (quote == '\'' || quote == '"')) {
+		return false;
+	} else if (s.text[0] >= 0x80) {
+		Rune r = -1;
+		isize size = gb_utf8_decode(s.text, s.len, &r);
+		*rune = r;
+		*tail_string = make_string(s.text+size, s.len-size);
+		return true;
+	} else if (s.text[0] != '\\') {
+		*rune = s.text[0];
+		*tail_string = make_string(s.text+1, s.len-1);
+		return true;
+	}
+
+	if (s.len <= 1) {
+		return false;
+	}
+	u8 c = s.text[1];
+	s = make_string(s.text+2, s.len-2);
+
+	switch (c) {
+	default: return false;
+
+	case 'a':  *rune = '\a'; break;
+	case 'b':  *rune = '\b'; break;
+	case 'f':  *rune = '\f'; break;
+	case 'n':  *rune = '\n'; break;
+	case 'r':  *rune = '\r'; break;
+	case 't':  *rune = '\t'; break;
+	case 'v':  *rune = '\v'; break;
+	case '\\': *rune = '\\'; break;
+
+
+	case '\'':
+	case '"':
+		if (c != quote) {
+			return false;
+		}
+		*rune = c;
+		break;
+
+	case '0':
+	case '1':
+	case '2':
+	case '3':
+	case '4':
+	case '5':
+	case '6':
+	case '7': {
+		i32 r = c - '0';
+		if (s.len < 2) {
+			return false;
+		}
+		for (isize i = 0; i < 2; i++) {
+			i32 d = s.text[i] - '0';
+			if (d < 0 || d > 7) {
+				return false;
+			}
+			r = (r<<3) | d;
+		}
+		s = make_string(s.text+2, s.len-2);
+		if (r > 0xff) {
+			return false;
+		}
+		*rune = r;
+	} break;
+
+	case 'x':
+	case 'u':
+	case 'U': {
+		isize n = 0;
+		switch (c) {
+		case 'x': n = 2; break;
+		case 'u': n = 4; break;
+		case 'U': n = 8; break;
+		}
+
+		Rune r = 0;
+		if (s.len < n) {
+			return false;
+		}
+		for (isize i = 0; i < n; i++) {
+			i32 d = gb_hex_digit_to_int(s.text[i]);
+			if (d < 0) {
+				return false;
+			}
+			r = (r<<4) | d;
+		}
+		s = make_string(s.text+n, s.len-n);
+		if (c == 'x') {
+			*rune = r;
+			break;
+		}
+		if (r > GB_RUNE_MAX) {
+			return false;
+		}
+		*rune = r;
+		*multi = true;
+	} break;
+	}
+	*tail_string = s;
+	return true;
+}
+
+
+// 0 == failure
+// 1 == original memory
+// 2 == new allocation
+i32 unquote_string(gbAllocator a, String *s_) {
+	GB_ASSERT(s_ != NULL);
+	String s = *s_;
+	isize n = s.len;
+	if (n < 2)
+		return 0;
+	u8 quote = s.text[0];
+	if (quote != s.text[n-1])
+		return 0;
+	s.text += 1;
+	s.len -= 2;
+
+	if (quote == '`') {
+		if (string_contains_char(s, '`')) {
+			return 0;
+		}
+		*s_ = s;
+		return 1;
+	}
+	if (quote != '"' && quote != '\'')
+		return 0;
+
+	if (string_contains_char(s, '\n'))
+		return 0;
+
+	if (!string_contains_char(s, '\\') && !string_contains_char(s, quote)) {
+		if (quote == '"') {
+			*s_ = s;
+			return 1;
+		} else if (quote == '\'') {
+			Rune r = GB_RUNE_INVALID;
+			isize size = gb_utf8_decode(s.text, s.len, &r);
+			if ((size == s.len) && (r != -1 || size != 1)) {
+				*s_ = s;
+				return 1;
+			}
+		}
+	}
+
+	u8 rune_temp[4] = {};
+	isize buf_len = 3*s.len / 2;
+	u8 *buf = gb_alloc_array(a, u8, buf_len);
+	isize len = 0;
+	while (s.len > 0) {
+		String tail_string = {};
+		Rune r = 0;
+		b32 multi = false;
+		b32 success = unquote_char(s, quote, &r, &multi, &tail_string);
+		if (!success) {
+			gb_free(a, buf);
+			return 0;
+		}
+		s = tail_string;
+
+		if (r < 0x80 || !multi) {
+			buf[len++] = cast(u8)r;
+		} else {
+			isize size = gb_utf8_encode_rune(rune_temp, r);
+			gb_memcopy(buf+len, rune_temp, size);
+			len += size;
+		}
+
+		if (quote == '\'' && s.len != 0) {
+			gb_free(a, buf);
+			return 0;
+		}
+	}
+	*s_ = make_string(buf, len);
+	return 2;
+}