std.Io: delete CountingWriter

lib/compiler/resinator/cvtres.zig

@@ -665,19 +665,16 @@ const ResourceTree = struct {
     pub fn writeCoff(
         self: *const ResourceTree,
         allocator: Allocator,
-        writer: anytype,
+        w: anytype,
         resources_in_data_order: []const Resource,
         lengths: Lengths,
         coff_string_table: *StringTable,
     ) ![]const std.coff.Symbol {
         if (self.type_to_name_map.count() == 0) {
-            try writer.writeByteNTimes(0, 16);
+            try w.writeByteNTimes(0, 16);
             return &.{};
         }
 
-        var counting_writer = std.io.countingWriter(writer);
-        const w = counting_writer.writer();
-
         var level2_list: std.ArrayListUnmanaged(*const NameToLanguageMap) = .empty;
         defer level2_list.deinit(allocator);
 
@@ -735,7 +732,6 @@ const ResourceTree = struct {
                 try level2_list.append(allocator, name_to_lang_map);
             }
         }
-        std.debug.assert(counting_writer.bytes_written == level2_start);
 
         const level3_start = level2_start + lengths.level2;
         var level3_address = level3_start;
@@ -771,7 +767,6 @@ const ResourceTree = struct {
                 try level3_list.append(allocator, lang_to_resources_map);
             }
         }
-        std.debug.assert(counting_writer.bytes_written == level3_start);
 
         var reloc_addresses = try allocator.alloc(u32, resources_in_data_order.len);
         defer allocator.free(reloc_addresses);
@@ -813,7 +808,6 @@ const ResourceTree = struct {
                 try resources_list.append(allocator, reloc_resource);
             }
         }
-        std.debug.assert(counting_writer.bytes_written == data_entries_start);
 
         for (resources_list.items, 0..) |reloc_resource, i| {
             // TODO: This logic works but is convoluted, would be good to clean this up
@@ -827,7 +821,6 @@ const ResourceTree = struct {
             };
             try w.writeStructEndian(data_entry, .little);
         }
-        std.debug.assert(counting_writer.bytes_written == strings_start);
 
         for (self.rsrc_string_table.keys()) |v| {
             const str = v.name;

lib/std/Io.zig

@@ -432,10 +432,6 @@ pub const FixedBufferStream = @import("Io/fixed_buffer_stream.zig").FixedBufferS
 /// Deprecated in favor of `Reader`.
 pub const fixedBufferStream = @import("Io/fixed_buffer_stream.zig").fixedBufferStream;
 /// Deprecated with no replacement; inefficient pattern
-pub const CountingWriter = @import("Io/counting_writer.zig").CountingWriter;
-/// Deprecated with no replacement; inefficient pattern
-pub const countingWriter = @import("Io/counting_writer.zig").countingWriter;
-/// Deprecated with no replacement; inefficient pattern
 pub const CountingReader = @import("Io/counting_reader.zig").CountingReader;
 /// Deprecated with no replacement; inefficient pattern
 pub const countingReader = @import("Io/counting_reader.zig").countingReader;
@@ -917,7 +913,6 @@ test {
     _ = Reader;
     _ = Writer;
     _ = BufferedWriter;
-    _ = CountingWriter;
     _ = CountingReader;
     _ = FixedBufferStream;
     _ = tty;

lib/std/Io/counting_writer.zig

@@ -1,39 +0,0 @@
-const std = @import("../std.zig");
-const io = std.io;
-const testing = std.testing;
-
-/// A Writer that counts how many bytes has been written to it.
-pub fn CountingWriter(comptime WriterType: type) type {
-    return struct {
-        bytes_written: u64,
-        child_stream: WriterType,
-
-        pub const Error = WriterType.Error;
-        pub const Writer = io.GenericWriter(*Self, Error, write);
-
-        const Self = @This();
-
-        pub fn write(self: *Self, bytes: []const u8) Error!usize {
-            const amt = try self.child_stream.write(bytes);
-            self.bytes_written += amt;
-            return amt;
-        }
-
-        pub fn writer(self: *Self) Writer {
-            return .{ .context = self };
-        }
-    };
-}
-
-pub fn countingWriter(child_stream: anytype) CountingWriter(@TypeOf(child_stream)) {
-    return .{ .bytes_written = 0, .child_stream = child_stream };
-}
-
-test CountingWriter {
-    var counting_stream = countingWriter(std.io.null_writer);
-    const stream = counting_stream.writer();
-
-    const bytes = "yay" ** 100;
-    stream.writeAll(bytes) catch unreachable;
-    try testing.expect(counting_stream.bytes_written == bytes.len);
-}

lib/std/crypto/phc_encoding.zig

@@ -5,6 +5,7 @@ const fmt = std.fmt;
 const io = std.io;
 const mem = std.mem;
 const meta = std.meta;
+const Writer = std.Io.Writer;
 
 const fields_delimiter = "$";
 const fields_delimiter_scalar = '$';
@@ -188,19 +189,20 @@ pub fn deserialize(comptime HashResult: type, str: []const u8) Error!HashResult
 ///
 /// `params` can also include any additional parameters.
 pub fn serialize(params: anytype, str: []u8) Error![]const u8 {
-    var buf = io.fixedBufferStream(str);
-    try serializeTo(params, buf.writer());
-    return buf.getWritten();
+    var w: Writer = .fixed(str);
+    serializeTo(params, &w) catch return error.NoSpaceLeft;
+    return w.buffered();
 }
 
 /// Compute the number of bytes required to serialize `params`
 pub fn calcSize(params: anytype) usize {
-    var buf = io.countingWriter(io.null_writer);
-    serializeTo(params, buf.writer()) catch unreachable;
-    return @as(usize, @intCast(buf.bytes_written));
+    var trash: [128]u8 = undefined;
+    var d: Writer.Discarding = .init(&trash);
+    serializeTo(params, &d.writer) catch unreachable;
+    return @intCast(d.fullCount());
 }
 
-fn serializeTo(params: anytype, out: anytype) !void {
+fn serializeTo(params: anytype, out: *std.Io.Writer) !void {
     const HashResult = @TypeOf(params);
 
     if (@hasField(HashResult, version_param_name)) {

lib/std/crypto/scrypt.zig

@@ -311,9 +311,10 @@ const crypt_format = struct {
 
     /// Compute the number of bytes required to serialize `params`
     pub fn calcSize(params: anytype) usize {
-        var buf = io.countingWriter(io.null_writer);
-        serializeTo(params, buf.writer()) catch unreachable;
-        return @as(usize, @intCast(buf.bytes_written));
+        var trash: [128]u8 = undefined;
+        var d: std.Io.Writer.Discarding = .init(&trash);
+        serializeTo(params, &d) catch unreachable;
+        return @intCast(d.fullCount());
     }
 
     fn serializeTo(params: anytype, out: anytype) !void {

src/arch/x86_64/encoder.zig

@@ -1204,11 +1204,10 @@ const TestEncode = struct {
         mnemonic: Instruction.Mnemonic,
         ops: []const Instruction.Operand,
     ) !void {
-        var stream = std.io.fixedBufferStream(&enc.buffer);
-        var count_writer = std.io.countingWriter(stream.writer());
+        var writer: std.Io.Writer = .fixed(&enc.buffer);
         const inst: Instruction = try .new(.none, mnemonic, ops);
-        try inst.encode(count_writer.writer(), .{});
-        enc.index = count_writer.bytes_written;
+        try inst.encode(&writer, .{});
+        enc.index = writer.bufferedLen();
     }
 
     fn code(enc: TestEncode) []const u8 {

src/link/Elf.zig

@@ -3152,10 +3152,11 @@ fn writeSyntheticSections(self: *Elf) !void {
 
     if (self.section_indexes.gnu_hash) |shndx| {
         const shdr = slice.items(.shdr)[shndx];
-        var buffer = try std.ArrayList(u8).initCapacity(gpa, self.gnu_hash.size());
-        defer buffer.deinit();
-        try self.gnu_hash.write(self, buffer.writer());
-        try self.pwriteAll(buffer.items, shdr.sh_offset);
+        var aw: std.Io.Writer.Allocating = .init(gpa);
+        try aw.ensureUnusedCapacity(self.gnu_hash.size());
+        defer aw.deinit();
+        try self.gnu_hash.write(self, &aw.writer);
+        try self.pwriteAll(aw.getWritten(), shdr.sh_offset);
     }
 
     if (self.section_indexes.versym) |shndx| {

src/link/Elf/synthetic_sections.zig

@@ -1237,17 +1237,14 @@ pub const GnuHashSection = struct {
         return header_size + hash.num_bloom * 8 + hash.num_buckets * 4 + hash.num_exports * 4;
     }
 
-    pub fn write(hash: GnuHashSection, elf_file: *Elf, writer: anytype) !void {
+    pub fn write(hash: GnuHashSection, elf_file: *Elf, writer: *std.Io.Writer) !void {
         const exports = getExports(elf_file);
         const export_off = elf_file.dynsym.count() - hash.num_exports;
 
-        var counting = std.io.countingWriter(writer);
-        const cwriter = counting.writer();
-
-        try cwriter.writeInt(u32, hash.num_buckets, .little);
-        try cwriter.writeInt(u32, export_off, .little);
-        try cwriter.writeInt(u32, hash.num_bloom, .little);
-        try cwriter.writeInt(u32, bloom_shift, .little);
+        try writer.writeInt(u32, hash.num_buckets, .little);
+        try writer.writeInt(u32, export_off, .little);
+        try writer.writeInt(u32, hash.num_bloom, .little);
+        try writer.writeInt(u32, bloom_shift, .little);
 
         const comp = elf_file.base.comp;
         const gpa = comp.gpa;
@@ -1271,7 +1268,7 @@ pub const GnuHashSection = struct {
             bloom[idx] |= @as(u64, 1) << @as(u6, @intCast((h >> bloom_shift) % 64));
         }
 
-        try cwriter.writeAll(mem.sliceAsBytes(bloom));
+        try writer.writeAll(mem.sliceAsBytes(bloom));
 
         // Fill in the hash bucket indices
         const buckets = try gpa.alloc(u32, hash.num_buckets);
@@ -1284,7 +1281,7 @@ pub const GnuHashSection = struct {
             }
         }
 
-        try cwriter.writeAll(mem.sliceAsBytes(buckets));
+        try writer.writeAll(mem.sliceAsBytes(buckets));
 
         // Finally, write the hash table
         const table = try gpa.alloc(u32, hash.num_exports);
@@ -1300,9 +1297,7 @@ pub const GnuHashSection = struct {
             }
         }
 
-        try cwriter.writeAll(mem.sliceAsBytes(table));
-
-        assert(counting.bytes_written == hash.size());
+        try writer.writeAll(mem.sliceAsBytes(table));
     }
 
     pub fn hasher(name: [:0]const u8) u32 {

src/link/MachO/dyld_info/Trie.zig

@@ -186,17 +186,18 @@ const FinalizeNodeResult = struct {
 
 /// Updates offset of this node in the output byte stream.
 fn finalizeNode(self: *Trie, node_index: Node.Index, offset_in_trie: u32) !FinalizeNodeResult {
-    var stream = std.io.countingWriter(std.io.null_writer);
-    const writer = stream.writer();
+    var trash_buffer: [64]u8 = undefined;
+    var stream: std.Io.Writer.Discarding = .init(&trash_buffer);
+    const writer = &stream.writer;
     const slice = self.nodes.slice();
 
     var node_size: u32 = 0;
     if (slice.items(.is_terminal)[node_index]) {
         const export_flags = slice.items(.export_flags)[node_index];
         const vmaddr_offset = slice.items(.vmaddr_offset)[node_index];
-        try leb.writeUleb128(writer, export_flags);
-        try leb.writeUleb128(writer, vmaddr_offset);
-        try leb.writeUleb128(writer, stream.bytes_written);
+        try writer.writeUleb128(export_flags);
+        try writer.writeUleb128(vmaddr_offset);
+        try writer.writeUleb128(stream.fullCount());
     } else {
         node_size += 1; // 0x0 for non-terminal nodes
     }
@@ -206,13 +207,13 @@ fn finalizeNode(self: *Trie, node_index: Node.Index, offset_in_trie: u32) !Final
         const edge = &self.edges.items[edge_index];
         const next_node_offset = slice.items(.trie_offset)[edge.node];
         node_size += @intCast(edge.label.len + 1);
-        try leb.writeUleb128(writer, next_node_offset);
+        try writer.writeUleb128(next_node_offset);
     }
 
     const trie_offset = slice.items(.trie_offset)[node_index];
     const updated = offset_in_trie != trie_offset;
     slice.items(.trie_offset)[node_index] = offset_in_trie;
-    node_size += @intCast(stream.bytes_written);
+    node_size += @intCast(stream.fullCount());
 
     return .{ .node_size = node_size, .updated = updated };
 }