Add `package path/filepath`; Add `os.stat` for windows (TODO: unix)

4 files changed, 625 insertions, 0 deletions

diff --git a/core/path/filepath/match.odin b/core/path/filepath/match.odin
new file mode 100644
index 000000000..01f899da3
--- /dev/null
+++ b/core/path/filepath/match.odin
@@ -0,0 +1,350 @@
+package filepath
+
+import "core:os"
+import "core:sort"
+import "core:strings"
+import "core:unicode/utf8"
+
+Match_Error :: enum {
+	None,
+	Syntax_Error,
+}
+
+// match states whether "name" matches the shell pattern
+// Pattern syntax is:
+//	pattern:
+//		{term}
+//	term:
+//		'*'	        matches any sequence of non-/ characters
+//		'?'             matches any single non-/ character
+//		'[' ['^']  { character-range } ']'
+//		                character classification (cannot be empty)
+//		c               matches character c (c != '*', '?', '\\', '[')
+//		'\\' c          matches character c
+//
+//	character-range
+//		c               matches character c (c != '\\', '-', ']')
+//		'\\' c          matches character c
+//		lo '-' hi       matches character c for lo <= c <= hi
+//
+// match requires that the pattern matches the entirety of the name, not just a substring
+// The only possible error returned is .Syntax_Error
+//
+// NOTE(bill): This is effectively the shell pattern matching system found
+//
+match :: proc(pattern, name: string) -> (matched: bool, err: Match_Error) {
+	pattern, name := pattern, name;
+	pattern_loop: for len(pattern) > 0 {
+		star: bool;
+		chunk: string;
+		star, chunk, pattern = scan_chunk(pattern);
+		if star && chunk == "" {
+			return !strings.contains(name, SEPARATOR_STRING), .None;
+		}
+
+		t: string;
+		ok: bool;
+		t, ok, err = match_chunk(chunk, name);
+
+		if ok && (len(t) == 0 || len(pattern) > 0) {
+			name = t;
+			continue;
+		}
+		if err != .None {
+			return;
+		}
+		if star {
+			for i := 0; i < len(name) && name[i] != SEPARATOR; i += 1 {
+				t, ok, err = match_chunk(chunk, name[i+1:]);
+				if ok {
+					if len(pattern) == 0 && len(t) > 0 {
+						continue;
+					}
+					name = t;
+					continue pattern_loop;
+				}
+				if err != .None {
+					return;
+				}
+			}
+		}
+
+		return false, .None;
+	}
+
+	return len(name) == 0, .None;
+}
+
+
+@(private="file")
+scan_chunk :: proc(pattern: string) -> (star: bool, chunk, rest: string) {
+	pattern := pattern;
+	for len(pattern) > 0 && pattern[0] == '*' {
+		pattern = pattern[1:];
+		star = true;
+	}
+	in_range := false;
+	i: int;
+
+	scan_loop: for i = 0; i < len(pattern); i += 1 {
+		switch pattern[i] {
+		case '\\':
+			when ODIN_OS != "windows" {
+				if i+1 < len(pattern) {
+					i += 1;
+				}
+			}
+		case '[':
+			in_range = true;
+		case ']':
+			in_range = false;
+		case '*':
+			if !in_range {
+				break scan_loop;
+			}
+
+		}
+	}
+	return star, pattern[:i], pattern[i:];
+}
+
+@(private="file")
+match_chunk :: proc(chunk, s: string) -> (rest: string, ok: bool, err: Match_Error) {
+	chunk, s := chunk, s;
+	for len(chunk) > 0 {
+		if len(s) == 0 {
+			return;
+		}
+		switch chunk[0] {
+		case '[':
+			r, w := utf8.decode_rune_in_string(s);
+			s = s[w:];
+			chunk = chunk[1:];
+			is_negated := false;
+			if len(chunk) > 0 && chunk[0] == '^' {
+				is_negated = true;
+				chunk = chunk[1:];
+			}
+			match := false;
+			range_count := 0;
+			for {
+				if len(chunk) > 0 && chunk[0] == ']' && range_count > 0 {
+					chunk = chunk[1:];
+					break;
+				}
+				lo, hi: rune;
+				if lo, chunk, err = get_escape(chunk); err != .None {
+					return;
+				}
+				hi = lo;
+				if chunk[0] == '-' {
+					if hi, chunk, err = get_escape(chunk[1:]); err != .None {
+						return;
+					}
+				}
+
+				if lo <= r && r <= hi {
+					match = true;
+				}
+				range_count += 1;
+			}
+			if match == is_negated {
+				return;
+			}
+
+		case '?':
+			if s[0] == SEPARATOR {
+				return;
+			}
+			_, w := utf8.decode_rune_in_string(s);
+			s = s[w:];
+			chunk = chunk[1:];
+
+		case '\\':
+			when ODIN_OS != "windows" {
+				chunk = chunk[1:];
+				if len(chunk) == 0 {
+					err = .Syntax_Error;
+					return;
+				}
+			}
+			fallthrough;
+		case:
+			if chunk[0] != s[0] {
+				return;
+			}
+			s = s[1:];
+			chunk = chunk[1:];
+
+		}
+	}
+	return s, true, .None;
+}
+
+@(private="file")
+get_escape :: proc(chunk: string) -> (r: rune, next_chunk: string, err: Match_Error) {
+	if len(chunk) == 0 || chunk[0] == '-' || chunk[0] == ']' {
+		err = .Syntax_Error;
+		return;
+	}
+	chunk := chunk;
+	if chunk[0] == '\\' && ODIN_OS != "windows" {
+		chunk = chunk[1:];
+		if len(chunk) == 0 {
+			err = .Syntax_Error;
+			return;
+		}
+	}
+
+	w: int;
+	r, w = utf8.decode_rune_in_string(chunk);
+	if r == utf8.RUNE_ERROR && w == 1 {
+		err = .Syntax_Error;
+	}
+
+	next_chunk = chunk[w:];
+	if len(next_chunk) == 0 {
+		err = .Syntax_Error;
+	}
+
+	return;
+}
+
+
+
+// glob returns the names of all files matching pattern or nil if there are no matching files
+// The syntax of patterns is the same as "match".
+// The pattern may describe hierarchical names such as /usr/*/bin (assuming '/' is a separator)
+//
+// glob ignores file system errors
+//
+glob :: proc(pattern: string, allocator := context.allocator) -> (matches: []string, err: Match_Error) {
+	if !has_meta(pattern) {
+		// TODO(bill): os.lstat on here to check for error
+		m := make([]string, 1, allocator);
+		m[0] = pattern;
+		return m[:], .None;
+	}
+
+	temp_buf: [8]byte;
+
+	dir, file := split(pattern);
+	volume_len := 0;
+	when ODIN_OS == "windows" {
+		volume_len, dir = clean_glob_path_windows(dir, temp_buf[:]);
+	} else {
+		dir = clean_glob_path(dir);
+	}
+
+	if !has_meta(dir[volume_len:]) {
+		m, e := _glob(dir, file, nil);
+		return m[:], e;
+	}
+
+	m: []string;
+	m, err = glob(dir);
+	if err != .None {
+		return;
+	}
+	dmatches := make([dynamic]string, 0, 0, allocator);
+	for d in m {
+		dmatches, err = _glob(d, file, &dmatches);
+		if err != .None {
+			break;
+		}
+	}
+	if len(dmatches) > 0 {
+		matches = dmatches[:];
+	}
+	return;
+}
+_glob :: proc(dir, pattern: string, matches: ^[dynamic]string) -> (m: [dynamic]string, e: Match_Error) {
+	if matches != nil {
+		m = matches^;
+	} else {
+		m = make([dynamic]string, 0, 0, context.allocator);
+	}
+
+
+	d, derr := os.open(dir);
+	if derr != 0 {
+		return;
+	}
+	defer os.close(d);
+
+	fi, ferr := os.stat(d);
+	if ferr != 0 {
+		os.file_info_delete(fi);
+		return;
+	}
+	if !fi.is_dir {
+		os.file_info_delete(fi);
+		return;
+	}
+
+
+	fis, _ := os.read_dir(d, -1);
+	sort.quick_sort_proc(fis, proc(a, b: os.File_Info) -> int {
+		return sort.compare_strings(a.name, b.name);
+	});
+	defer {
+		for fi in fis {
+			os.file_info_delete(fi);
+		}
+		delete(fis);
+	}
+
+	for fi in fis {
+		n := fi.name;
+		matched, err := match(pattern, n);
+		if err != nil {
+			return m, err;
+		}
+		if matched {
+			append(&m, join(dir, n));
+		}
+	}
+	return;
+}
+
+@(private)
+has_meta :: proc(path: string) -> bool {
+	when ODIN_OS == "windows" {
+		CHARS :: `*?[`;
+	} else {
+		CHARS :: `*?[\`;
+	}
+	return strings.contains_any(path, CHARS);
+}
+
+@(private)
+clean_glob_path :: proc(path: string) -> string {
+	switch path {
+	case "":
+		return ".";
+	case SEPARATOR_STRING:
+		return path;
+	}
+	return path[:len(path)-1];
+}
+
+
+@(private)
+clean_glob_path_windows :: proc(path: string, temp_buf: []byte) -> (prefix_len: int, cleaned: string) {
+	vol_len := volume_name_len(path);
+	switch {
+	case path == "":
+		return 0, ".";
+	case vol_len+1 == len(path) && is_separator(path[len(path)-1]): // /, \, C:\, C:/
+		return vol_len+1, path;
+	case vol_len == len(path) && len(path) == 2: // C:
+		copy(temp_buf[:], path);
+		temp_buf[2] = '.';
+		return vol_len, string(temp_buf[:3]);
+	}
+
+	if vol_len >= len(path) {
+		vol_len = len(path) -1;
+	}
+	return vol_len, path[:len(path)-1];
+}
diff --git a/core/path/filepath/path.odin b/core/path/filepath/path.odin
new file mode 100644
index 000000000..c15ff110a
--- /dev/null
+++ b/core/path/filepath/path.odin
@@ -0,0 +1,199 @@
+package filepath
+
+import "core:os"
+import "core:strings"
+
+// is_separator checks whether the byte is a valid separator character
+is_separator :: proc(c: byte) -> bool {
+	switch c {
+	case '/':  return true;
+	case '\\': return ODIN_OS == "windows";
+	}
+	return false;
+}
+
+@(private)
+is_slash :: proc(c: byte) -> bool {
+	return c == '\\' || c == '/';
+}
+
+split :: proc(path: string) -> (dir, file: string) {
+	vol := volume_name(path);
+	i := len(path) - 1;
+	for i >= len(vol) && !is_separator(path[i]) {
+		i -= 1;
+	}
+	return path[:i+1], path[i+1:];
+}
+
+volume_name :: proc(path: string) -> string {
+	return path[:volume_name_len(path)];
+}
+
+volume_name_len :: proc(path: string) -> int {
+	if len(path) < 2 {
+		return 0;
+	}
+	c := path[0];
+	if path[1] == ':' {
+		switch c {
+		case 'a'..'z', 'A'..'Z':
+			return 2;
+		}
+	}
+
+	if l := len(path); l >= 5 && is_slash(path[0]) && is_slash(path[1]) &&
+		!is_slash(path[2]) && path[2] != '.' {
+		for n := 3; n < l-1; n += 1 {
+			if is_slash(path[n]) {
+				n += 1;
+				if !is_slash(path[n]) {
+					if path[n] == '.' {
+						break;
+					}
+				}
+				for ; n < l; n += 1 {
+					if is_slash(path[n]) {
+						break;
+					}
+				}
+				return n;
+			}
+			break;
+		}
+	}
+	return 0;
+}
+
+
+clean :: proc(path: string, allocator := context.allocator) -> string {
+	context.allocator = allocator;
+
+	path := path;
+	original_path := path;
+	vol_len := volume_name_len(path);
+	path = path[vol_len:];
+
+	if path == "" {
+		if vol_len > 1 && original_path[1] != ':' {
+			return from_slash(original_path);
+		}
+		return strings.concatenate({original_path, "."});
+	}
+
+	rooted := is_separator(path[0]);
+
+	n := len(path);
+	out := &Lazy_Buffer{
+		s = path,
+		vol_and_path = original_path,
+		vol_len = vol_len,
+	};
+
+	r, dot_dot := 0, 0;
+	if rooted {
+		lazy_buffer_append(out, '/');
+		r, dot_dot = 1, 1;
+	}
+
+	for r < n {
+		switch {
+		case is_separator(path[r]):
+			r += 1;
+		case path[r] == '.' && (r+1 == n || is_separator(path[r+1])):
+			r += 1;
+		case path[r] == '.' && path[r+1] == '.' && (r+2 == n || is_separator(path[r+2])):
+			r += 2;
+			switch {
+			case out.w > dot_dot:
+				out.w -= 1;
+				for out.w > dot_dot && !is_separator(lazy_buffer_index(out, out.w)) {
+					out.w -= 1;
+				}
+			case !rooted:
+				if out.w > 0 {
+					lazy_buffer_append(out, '/');
+				}
+				lazy_buffer_append(out, '.');
+				lazy_buffer_append(out, '.');
+				dot_dot = out.w;
+			}
+		case:
+			if rooted && out.w != 1 || !rooted && out.w != 0 {
+				lazy_buffer_append(out, '/');
+			}
+			for ; r < n && !is_separator(path[r]); r += 1 {
+				lazy_buffer_append(out, path[r]);
+			}
+
+		}
+	}
+
+	if out.w == 0 {
+		lazy_buffer_append(out, '.');
+	}
+
+	s := lazy_buffer_string(out);
+	cleaned := from_slash(s);
+	return cleaned;
+}
+
+from_slash :: proc(path: string, allocator := context.allocator) -> string {
+	if SEPARATOR == '/' {
+		return path;
+	}
+	s, ok := strings.replace_all(path, "/", SEPARATOR_STRING, allocator);
+	if !ok {
+		s = strings.clone(s, allocator);
+	}
+	return s;
+}
+
+
+
+/*
+	Lazy_Buffer is a lazily made path buffer
+	When it does allocate, it uses the context.allocator
+ */
+@(private)
+Lazy_Buffer :: struct {
+	s: string,
+	b: []byte,
+	w: int, // write index
+	vol_and_path: string,
+	vol_len:      int,
+}
+
+@(private)
+lazy_buffer_index :: proc(lb: ^Lazy_Buffer, i: int) -> byte {
+	if lb.b != nil {
+		return lb.b[i];
+	}
+	return lb.s[i];
+}
+@(private)
+lazy_buffer_append :: proc(lb: ^Lazy_Buffer, c: byte) {
+	if lb.b == nil {
+		if lb.w < len(lb.s) && lb.s[lb.w] == c {
+			lb.w += 1;
+			return;
+		}
+		lb.b = make([]byte, len(lb.s));
+		copy(lb.b, lb.s[:lb.w]);
+	}
+	lb.b[lb.w] = c;
+	lb.w += 1;
+}
+@(private)
+lazy_buffer_string :: proc(lb: ^Lazy_Buffer) -> string {
+	if lb.b == nil {
+		return strings.clone(lb.vol_and_path[:lb.vol_len+lb.w]);
+	}
+
+	x := lb.vol_and_path[:lb.vol_len];
+	y := string(lb.b[:lb.w]);
+	z := make([]byte, len(x)+len(y));
+	copy(z, x);
+	copy(z[len(x):], y);
+	return string(z);
+}
diff --git a/core/path/filepath/path_unix.odin b/core/path/filepath/path_unix.odin
new file mode 100644
index 000000000..7ffe6291e
--- /dev/null
+++ b/core/path/filepath/path_unix.odin
@@ -0,0 +1,5 @@
+//+build linux, darwin, freebsd
+package filepath
+
+SEPARATOR :: '/';
+SEPARATOR_STRING :: `/`;
diff --git a/core/path/filepath/path_windows.odin b/core/path/filepath/path_windows.odin
new file mode 100644
index 000000000..604859ca8
--- /dev/null
+++ b/core/path/filepath/path_windows.odin
@@ -0,0 +1,71 @@
+package filepath
+
+import "core:strings"
+
+SEPARATOR :: '\\';
+SEPARATOR_STRING :: `\`;
+
+
+reserved_names := []string{
+	"CON", "PRN", "AUX", "NUL",
+	"COM1", "COM2", "COM3", "COM4", "COM5", "COM6", "COM7", "COM8", "COM9",
+	"LPT1", "LPT2", "LPT3", "LPT4", "LPT5", "LPT6", "LPT7", "LPT8", "LPT9",
+};
+
+is_reserved_name :: proc(path: string) -> bool {
+	if len(path) == 0 {
+		return false;
+	}
+	for reserved in reserved_names {
+		if strings.equal_fold(path, reserved) {
+			return true;
+		}
+	}
+	return false;
+}
+
+is_UNC :: proc(path: string) -> bool {
+	return volume_name_len(path) > 2;
+}
+
+join :: proc(elems: ..string, allocator := context.allocator) -> string {
+	for e, i in elems {
+		if e != "" {
+			return join_non_empty(elems[i:]);
+		}
+	}
+	return "";
+}
+
+join_non_empty :: proc(elems: []string) -> string {
+	if len(elems[0]) == 2 && elems[0][1] == ':' {
+		i := 1;
+		for ; i < len(elems); i += 1 {
+			if elems[i] != "" {
+				break;
+			}
+		}
+		s := strings.join(elems[i:], SEPARATOR_STRING, context.temp_allocator);
+		s = strings.concatenate({elems[0], s}, context.temp_allocator);
+		return clean(s);
+	}
+
+	s := strings.join(elems, SEPARATOR_STRING, context.temp_allocator);
+	p := clean(s);
+	if !is_UNC(p) {
+		return p;
+	}
+
+	head := clean(elems[0], context.temp_allocator);
+	if is_UNC(head) {
+		return p;
+	}
+	delete(p); // It is not needed now
+
+	tail := clean(strings.join(elems[1:], SEPARATOR_STRING, context.temp_allocator), context.temp_allocator);
+	if head[len(head)-1] == SEPARATOR {
+		return strings.concatenate({head, tail});
+	}
+
+	return strings.concatenate({head, SEPARATOR_STRING, tail});
+}