From 5f4e4cc81178dc7cd3d2f5cda6c1c362b9a9321b Mon Sep 17 00:00:00 2001
From: kayomn <kayomn@kayomn.net>
Date: Sat, 15 Oct 2022 11:38:22 +0100
Subject: [PATCH] Implement more hash table logic

---
 src/main.zig  |  4 +---
 src/sys.zig   | 12 +++++++-----
 src/table.zig | 48 ++++++++++++++++++++++++++++++++++++++----------
 3 files changed, 46 insertions(+), 18 deletions(-)

diff --git a/src/main.zig b/src/main.zig
index 9b95b9d..2f85626 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -11,9 +11,7 @@ const sys = @import("./sys.zig");
 /// Entry point.
 ///
 pub fn main() anyerror!void {
-    var gpa = std.heap.GeneralPurposeAllocator(.{}){};
-
-    return nosuspend await async sys.runGraphics(gpa.allocator(), anyerror, run);
+    return nosuspend await async sys.runGraphics(anyerror, run);
 }
 
 test {
diff --git a/src/sys.zig b/src/sys.zig
index cbfe2a8..e431003 100644
--- a/src/sys.zig
+++ b/src/sys.zig
@@ -819,7 +819,7 @@ pub const RunError = error {
 /// Should an error from `run` occur, an `Error` is returned, otherwise a [RunError] is returned if
 /// the underlying runtime fails and is logged.
 ///
-pub fn runGraphics(allocator: std.mem.Allocator, comptime Error: anytype,
+pub fn runGraphics(comptime Error: anytype,
     comptime run: GraphicsRunner(Error)) (RunError || Error)!void {
 
     if (ext.SDL_Init(ext.SDL_INIT_EVERYTHING) != 0) {
@@ -856,13 +856,15 @@ pub fn runGraphics(allocator: std.mem.Allocator, comptime Error: anytype,
     defer ext.SDL_DestroyRenderer(renderer);
 
     var cwd_file_system = FileSystem{.native =.{.path_prefix = "./"}};
+    var data_access = try (try cwd_file_system.joinedPath(&.{"./data.oar"})).open(.readonly);
 
-    var data_archive_file_access = try (try cwd_file_system.
-        joinedPath(&.{"./data.oar"})).open(.readonly);
+    defer data_access.close();
 
-    defer data_archive_file_access.close();
+    var gpa = std.heap.GeneralPurposeAllocator(.{}){};
 
-    var app_context = AppContext.Implementation.init(allocator, data_archive_file_access) catch |err| {
+    defer _ = gpa.deinit();
+
+    var app_context = AppContext.Implementation.init(gpa.allocator(), data_access) catch |err| {
         ext.SDL_LogCritical(ext.SDL_LOG_CATEGORY_APPLICATION, switch (err) {
             error.OutOfMemory => "Failed to allocate necessary memory",
             error.OutOfMutexes => "Failed to create file-system work lock",
diff --git a/src/table.zig b/src/table.zig
index c89439c..aecd12d 100644
--- a/src/table.zig
+++ b/src/table.zig
@@ -32,6 +32,29 @@ pub fn Hashed(comptime Key: type, comptime Value: type,
         ///
         const Self = @This();
 
+        ///
+        /// Deinitializes `self`, preventing any further use.
+        ///
+        pub fn deinit(self: *Self) void {
+            self.allocator.free(self.buckets);
+
+            self.buckets = &.{};
+        }
+
+        ///
+        /// Initializes a [Self] using `allocator` as the memory allocation strategy.
+        ///
+        /// Returns a new [Self] value or an [Allocator.Error] if initializing failed.
+        ///
+        pub fn init(allocator: Allocator) Allocator.Error!Self {
+            return Self{
+                .buckets = try allocator.alloc(Bucket, 4),
+                .filled = 0,
+                .allocator = allocator,
+                .load_limit = 0.75,
+            };
+        }
+
         ///
         /// Searches for `key` to delete it, returning the deleted value or `null` if no matching
         /// key was found.
@@ -62,15 +85,6 @@ pub fn Hashed(comptime Key: type, comptime Value: type,
             return null;
         }
 
-        pub fn init(allocator: Allocator) Allocator.Error!Self {
-            return Self{
-                .buckets = try allocator.alloc(Bucket, 4),
-                .filled = 0,
-                .allocator = allocator,
-                .load_limit = 0.75,
-            };
-        }
-
         ///
         /// Attempts to insert the value at `key` to be `value` in `self`, returning an
         /// [InsertError] if it fails.
@@ -137,12 +151,17 @@ pub fn Hashed(comptime Key: type, comptime Value: type,
 }
 
 ///
-///
+/// [InsertError.KeyExists] occurs when an insertion was attempted on a table with a matching key
+/// already present.
 ///
 pub const InsertError = std.mem.Allocator.Error || error {
     KeyExists,
 };
 
+///
+/// Returns a context type for handling `Key` as a key in a table, associating hashing and equality
+/// behaviors to it.
+///
 pub fn KeyContext(comptime Key: type) type {
     return struct {
         hash: fn (Key) usize,
@@ -150,10 +169,16 @@ pub fn KeyContext(comptime Key: type) type {
     };
 }
 
+///
+/// Tests if the contents of `this_string` lexically equals the contents of `that_string`.
+///
 fn equalsString(this_string: []const u8, that_string: []const u8) bool {
     return std.mem.eql(u8, this_string, that_string);
 }
 
+///
+/// Hashes `string` into a hash value of `usize`.
+///
 fn hashString(string: []const u8) usize {
     var hash = @as(usize, 5381);
 
@@ -162,6 +187,9 @@ fn hashString(string: []const u8) usize {
     return hash;
 }
 
+///
+/// A [KeyContext] for handling `[]const u8` types.
+///
 pub const string_context = KeyContext([]const u8){
     .hash = hashString,
     .equals = equalsString,