link: commit missing source StringTable.zig

src/link/StringTable.zig

@@ -0,0 +1,49 @@
+buffer: std.ArrayListUnmanaged(u8) = .{},
+table: std.HashMapUnmanaged(u32, void, StringIndexContext, std.hash_map.default_max_load_percentage) = .{},
+
+pub fn deinit(self: *Self, gpa: Allocator) void {
+    self.buffer.deinit(gpa);
+    self.table.deinit(gpa);
+}
+
+pub fn insert(self: *Self, gpa: Allocator, string: []const u8) !u32 {
+    const gop = try self.table.getOrPutContextAdapted(gpa, @as([]const u8, string), StringIndexAdapter{
+        .bytes = &self.buffer,
+    }, StringIndexContext{
+        .bytes = &self.buffer,
+    });
+    if (gop.found_existing) return gop.key_ptr.*;
+
+    try self.buffer.ensureUnusedCapacity(gpa, string.len + 1);
+    const new_off = @as(u32, @intCast(self.buffer.items.len));
+
+    self.buffer.appendSliceAssumeCapacity(string);
+    self.buffer.appendAssumeCapacity(0);
+
+    gop.key_ptr.* = new_off;
+
+    return new_off;
+}
+
+pub fn getOffset(self: *Self, string: []const u8) ?u32 {
+    return self.table.getKeyAdapted(string, StringIndexAdapter{
+        .bytes = &self.buffer,
+    });
+}
+
+pub fn get(self: Self, off: u32) ?[:0]const u8 {
+    if (off >= self.buffer.items.len) return null;
+    return mem.sliceTo(@as([*:0]const u8, @ptrCast(self.buffer.items.ptr + off)), 0);
+}
+
+pub fn getAssumeExists(self: Self, off: u32) [:0]const u8 {
+    return self.get(off) orelse unreachable;
+}
+
+const std = @import("std");
+const mem = std.mem;
+
+const Allocator = mem.Allocator;
+const Self = @This();
+const StringIndexAdapter = std.hash_map.StringIndexAdapter;
+const StringIndexContext = std.hash_map.StringIndexContext;