1 files changed, 243 insertions, 0 deletions

diff --git a/codegen/dwp.zig b/codegen/dwp.zig
new file mode 100644
index 0000000..a8cef57
--- /dev/null
+++ b/codegen/dwp.zig
@@ -0,0 +1,243 @@
+const std = @import("std");
+
+const block_size = 256;
+const Block = [block_size]i3;
+
+const BlockMap = std.HashMap(
+    Block,
+    u16,
+    struct {
+        pub fn hash(_: @This(), k: Block) u64 {
+            var hasher = std.hash.Wyhash.init(0);
+            std.hash.autoHashStrat(&hasher, k, .DeepRecursive);
+            return hasher.final();
+        }
+
+        pub fn eql(_: @This(), a: Block, b: Block) bool {
+            return std.mem.eql(i3, &a, &b);
+        }
+    },
+    std.hash_map.default_max_load_percentage,
+);
+
+pub fn main() !void {
+    var arena = std.heap.ArenaAllocator.init(std.heap.page_allocator);
+    defer arena.deinit();
+    const allocator = arena.allocator();
+
+    var flat_map = std.AutoHashMap(u21, i3).init(allocator);
+    defer flat_map.deinit();
+
+    var line_buf: [4096]u8 = undefined;
+
+    // Process DerivedEastAsianWidth.txt
+    var deaw_file = try std.fs.cwd().openFile("unicode/extracted/DerivedEastAsianWidth.txt", .{});
+    defer deaw_file.close();
+    var deaw_buf = std.io.bufferedReader(deaw_file.reader());
+    const deaw_reader = deaw_buf.reader();
+
+    while (try deaw_reader.readUntilDelimiterOrEof(&line_buf, '\n')) |line| {
+        if (line.len == 0) continue;
+
+        // @missing ranges
+        if (std.mem.startsWith(u8, line, "# @missing: ")) {
+            const semi = std.mem.indexOfScalar(u8, line, ';').?;
+            const field = line[12..semi];
+            const dots = std.mem.indexOf(u8, field, "..").?;
+            const from = try std.fmt.parseInt(u21, field[0..dots], 16);
+            const to = try std.fmt.parseInt(u21, field[dots + 2 ..], 16);
+            if (from == 0 and to == 0x10ffff) continue;
+            for (from..to + 1) |cp| try flat_map.put(@intCast(cp), 2);
+            continue;
+        }
+
+        if (line[0] == '#') continue;
+
+        const no_comment = if (std.mem.indexOfScalar(u8, line, '#')) |octo| line[0..octo] else line;
+
+        var field_iter = std.mem.tokenizeAny(u8, no_comment, "; ");
+        var current_code: [2]u21 = undefined;
+
+        var i: usize = 0;
+        while (field_iter.next()) |field| : (i += 1) {
+            switch (i) {
+                0 => {
+                    // Code point(s)
+                    if (std.mem.indexOf(u8, field, "..")) |dots| {
+                        current_code = .{
+                            try std.fmt.parseInt(u21, field[0..dots], 16),
+                            try std.fmt.parseInt(u21, field[dots + 2 ..], 16),
+                        };
+                    } else {
+                        const code = try std.fmt.parseInt(u21, field, 16);
+                        current_code = .{ code, code };
+                    }
+                },
+                1 => {
+                    // Width
+                    if (std.mem.eql(u8, field, "W") or std.mem.eql(u8, field, "F")) {
+                        for (current_code[0]..current_code[1] + 1) |cp| try flat_map.put(@intCast(cp), 2);
+                    }
+                },
+                else => {},
+            }
+        }
+    }
+
+    // Process DerivedGeneralCategory.txt
+    var dgc_file = try std.fs.cwd().openFile("unicode/extracted/DerivedGeneralCategory.txt", .{});
+    defer dgc_file.close();
+    var dgc_buf = std.io.bufferedReader(dgc_file.reader());
+    const dgc_reader = dgc_buf.reader();
+
+    while (try dgc_reader.readUntilDelimiterOrEof(&line_buf, '\n')) |line| {
+        if (line.len == 0 or line[0] == '#') continue;
+        const no_comment = if (std.mem.indexOfScalar(u8, line, '#')) |octo| line[0..octo] else line;
+
+        var field_iter = std.mem.tokenizeAny(u8, no_comment, "; ");
+        var current_code: [2]u21 = undefined;
+
+        var i: usize = 0;
+        while (field_iter.next()) |field| : (i += 1) {
+            switch (i) {
+                0 => {
+                    // Code point(s)
+                    if (std.mem.indexOf(u8, field, "..")) |dots| {
+                        current_code = .{
+                            try std.fmt.parseInt(u21, field[0..dots], 16),
+                            try std.fmt.parseInt(u21, field[dots + 2 ..], 16),
+                        };
+                    } else {
+                        const code = try std.fmt.parseInt(u21, field, 16);
+                        current_code = .{ code, code };
+                    }
+                },
+                1 => {
+                    // General category
+                    if (std.mem.eql(u8, field, "Mn")) {
+                        // Nonspacing_Mark
+                        for (current_code[0]..current_code[1] + 1) |cp| try flat_map.put(@intCast(cp), 0);
+                    } else if (std.mem.eql(u8, field, "Me")) {
+                        // Enclosing_Mark
+                        for (current_code[0]..current_code[1] + 1) |cp| try flat_map.put(@intCast(cp), 0);
+                    } else if (std.mem.eql(u8, field, "Mc")) {
+                        // Spacing_Mark
+                        for (current_code[0]..current_code[1] + 1) |cp| try flat_map.put(@intCast(cp), 0);
+                    } else if (std.mem.eql(u8, field, "Cf")) {
+                        if (std.mem.indexOf(u8, line, "ARABIC") == null) {
+                            // Format except Arabic
+                            for (current_code[0]..current_code[1] + 1) |cp| try flat_map.put(@intCast(cp), 0);
+                        }
+                    }
+                },
+                else => {},
+            }
+        }
+    }
+
+    var blocks_map = BlockMap.init(allocator);
+    defer blocks_map.deinit();
+
+    var stage1 = std.ArrayList(u16).init(allocator);
+    defer stage1.deinit();
+
+    var stage2 = std.ArrayList(i3).init(allocator);
+    defer stage2.deinit();
+
+    var block: Block = [_]i3{0} ** block_size;
+    var block_len: u16 = 0;
+
+    for (0..0x110000) |i| {
+        const cp: u21 = @intCast(i);
+        var width = flat_map.get(cp) orelse 1;
+
+        // Specific overrides
+        switch (cp) {
+            // Three-em dash
+            0x2e3b => width = 3,
+
+            // C0/C1 control codes
+            0...0x20,
+            0x80...0xa0,
+
+            // Line separator
+            0x2028,
+
+            // Paragraph separator
+            0x2029,
+
+            // Hangul syllable and ignorable.
+            0x1160...0x11ff,
+            0xd7b0...0xd7ff,
+            0x2060...0x206f,
+            0xfff0...0xfff8,
+            0xe0000...0xE0fff,
+
+            // Sk with EMOJI MODIFIER comment
+            0x1f3fb...0x1f3ff,
+            => width = 0,
+
+            // Two-em dash
+            0x2e3a,
+
+            // Regional indicators
+            0x1f1e6...0x1f200,
+
+            // CJK Blocks
+            0x3400...0x4dbf, // CJK Unified Ideographs Extension A
+            0x4e00...0x9fff, // CJK Unified Ideographs
+            0xf900...0xfaff, // CJK Compatibility Ideographs
+            0x20000...0x2fffd, // Plane 2
+            0x30000...0x3fffd, // Plane 3
+            => width = 2,
+
+            else => {},
+        }
+
+        // ASCII
+        if (0x20 <= cp and cp < 0x7f) width = 1;
+
+        // Soft hyphen
+        if (cp == 0xad) width = 1;
+
+        // Backspace and delete
+        if (cp == 0x8 or cp == 0x7f) width = -1;
+
+        // Process block
+        block[block_len] = width;
+        block_len += 1;
+
+        if (block_len < block_size and cp != 0x10ffff) continue;
+
+        const gop = try blocks_map.getOrPut(block);
+        if (!gop.found_existing) {
+            gop.value_ptr.* = @intCast(stage2.items.len);
+            try stage2.appendSlice(&block);
+        }
+
+        try stage1.append(gop.value_ptr.*);
+        block_len = 0;
+    }
+
+    var args_iter = std.process.args();
+    _ = args_iter.skip();
+    const output_path = args_iter.next() orelse @panic("No output file arg!");
+
+    var out_file = try std.fs.cwd().createFile(output_path, .{});
+    defer out_file.close();
+    var out_buf = std.io.bufferedWriter(out_file.writer());
+    const writer = out_buf.writer();
+
+    try writer.writeAll("const std = @import(\"std\");\n");
+
+    try writer.print("const Stage2Int = std.math.IntFittingRange(0, {});\n", .{stage2.items.len});
+    try writer.print("pub const stage_1 = [{}]Stage2Int{{", .{stage1.items.len});
+    for (stage1.items) |v| try writer.print("{},", .{v});
+    try writer.writeAll("};\n");
+
+    try writer.print("pub const stage_2 = [{}]i3{{", .{stage2.items.len});
+    for (stage2.items) |v| try writer.print("{},", .{v});
+    try writer.writeAll("};\n");
+
+    try out_buf.flush();
+}