combine std.build and std.build.Builder into std.Build

I've been wanting to do this for along time.

1 files changed, 0 insertions, 1026 deletions

diff --git a/lib/std/build/CheckObjectStep.zig b/lib/std/build/CheckObjectStep.zig
deleted file mode 100644
index 4ef350b418..0000000000
--- a/lib/std/build/CheckObjectStep.zig
+++ /dev/null
@@ -1,1026 +0,0 @@
-const std = @import("../std.zig");
-const assert = std.debug.assert;
-const build = std.build;
-const fs = std.fs;
-const macho = std.macho;
-const math = std.math;
-const mem = std.mem;
-const testing = std.testing;
-
-const CheckObjectStep = @This();
-
-const Allocator = mem.Allocator;
-const Builder = build.Builder;
-const Step = build.Step;
-const EmulatableRunStep = build.EmulatableRunStep;
-
-pub const base_id = .check_object;
-
-step: Step,
-builder: *Builder,
-source: build.FileSource,
-max_bytes: usize = 20 * 1024 * 1024,
-checks: std.ArrayList(Check),
-dump_symtab: bool = false,
-obj_format: std.Target.ObjectFormat,
-
-pub fn create(builder: *Builder, source: build.FileSource, obj_format: std.Target.ObjectFormat) *CheckObjectStep {
-    const gpa = builder.allocator;
-    const self = gpa.create(CheckObjectStep) catch unreachable;
-    self.* = .{
-        .builder = builder,
-        .step = Step.init(.check_file, "CheckObject", gpa, make),
-        .source = source.dupe(builder),
-        .checks = std.ArrayList(Check).init(gpa),
-        .obj_format = obj_format,
-    };
-    self.source.addStepDependencies(&self.step);
-    return self;
-}
-
-/// Runs and (optionally) compares the output of a binary.
-/// Asserts `self` was generated from an executable step.
-pub fn runAndCompare(self: *CheckObjectStep) *EmulatableRunStep {
-    const dependencies_len = self.step.dependencies.items.len;
-    assert(dependencies_len > 0);
-    const exe_step = self.step.dependencies.items[dependencies_len - 1];
-    const exe = exe_step.cast(std.build.LibExeObjStep).?;
-    const emulatable_step = EmulatableRunStep.create(self.builder, "EmulatableRun", exe);
-    emulatable_step.step.dependOn(&self.step);
-    return emulatable_step;
-}
-
-/// There two types of actions currently suported:
-/// * `.match` - is the main building block of standard matchers with optional eat-all token `{*}`
-/// and extractors by name such as `{n_value}`. Please note this action is very simplistic in nature
-/// i.e., it won't really handle edge cases/nontrivial examples. But given that we do want to use
-/// it mainly to test the output of our object format parser-dumpers when testing the linkers, etc.
-/// it should be plenty useful in its current form.
-/// * `.compute_cmp` - can be used to perform an operation on the extracted global variables
-/// using the MatchAction. It currently only supports an addition. The operation is required
-/// to be specified in Reverse Polish Notation to ease in operator-precedence parsing (well,
-/// to avoid any parsing really).
-/// For example, if the two extracted values were saved as `vmaddr` and `entryoff` respectively
-/// they could then be added with this simple program `vmaddr entryoff +`.
-const Action = struct {
-    tag: enum { match, not_present, compute_cmp },
-    phrase: []const u8,
-    expected: ?ComputeCompareExpected = null,
-
-    /// Will return true if the `phrase` was found in the `haystack`.
-    /// Some examples include:
-    ///
-    /// LC 0                     => will match in its entirety
-    /// vmaddr {vmaddr}          => will match `vmaddr` and then extract the following value as u64
-    ///                             and save under `vmaddr` global name (see `global_vars` param)
-    /// name {*}libobjc{*}.dylib => will match `name` followed by a token which contains `libobjc` and `.dylib`
-    ///                             in that order with other letters in between
-    fn match(act: Action, haystack: []const u8, global_vars: anytype) !bool {
-        assert(act.tag == .match or act.tag == .not_present);
-
-        var candidate_var: ?struct { name: []const u8, value: u64 } = null;
-        var hay_it = mem.tokenize(u8, mem.trim(u8, haystack, " "), " ");
-        var needle_it = mem.tokenize(u8, mem.trim(u8, act.phrase, " "), " ");
-
-        while (needle_it.next()) |needle_tok| {
-            const hay_tok = hay_it.next() orelse return false;
-
-            if (mem.indexOf(u8, needle_tok, "{*}")) |index| {
-                // We have fuzzy matchers within the search pattern, so we match substrings.
-                var start = index;
-                var n_tok = needle_tok;
-                var h_tok = hay_tok;
-                while (true) {
-                    n_tok = n_tok[start + 3 ..];
-                    const inner = if (mem.indexOf(u8, n_tok, "{*}")) |sub_end|
-                        n_tok[0..sub_end]
-                    else
-                        n_tok;
-                    if (mem.indexOf(u8, h_tok, inner) == null) return false;
-                    start = mem.indexOf(u8, n_tok, "{*}") orelse break;
-                }
-            } else if (mem.startsWith(u8, needle_tok, "{")) {
-                const closing_brace = mem.indexOf(u8, needle_tok, "}") orelse return error.MissingClosingBrace;
-                if (closing_brace != needle_tok.len - 1) return error.ClosingBraceNotLast;
-
-                const name = needle_tok[1..closing_brace];
-                if (name.len == 0) return error.MissingBraceValue;
-                const value = try std.fmt.parseInt(u64, hay_tok, 16);
-                candidate_var = .{
-                    .name = name,
-                    .value = value,
-                };
-            } else {
-                if (!mem.eql(u8, hay_tok, needle_tok)) return false;
-            }
-        }
-
-        if (candidate_var) |v| {
-            try global_vars.putNoClobber(v.name, v.value);
-        }
-
-        return true;
-    }
-
-    /// Will return true if the `phrase` is correctly parsed into an RPN program and
-    /// its reduced, computed value compares using `op` with the expected value, either
-    /// a literal or another extracted variable.
-    fn computeCmp(act: Action, gpa: Allocator, global_vars: anytype) !bool {
-        var op_stack = std.ArrayList(enum { add, sub, mod, mul }).init(gpa);
-        var values = std.ArrayList(u64).init(gpa);
-
-        var it = mem.tokenize(u8, act.phrase, " ");
-        while (it.next()) |next| {
-            if (mem.eql(u8, next, "+")) {
-                try op_stack.append(.add);
-            } else if (mem.eql(u8, next, "-")) {
-                try op_stack.append(.sub);
-            } else if (mem.eql(u8, next, "%")) {
-                try op_stack.append(.mod);
-            } else if (mem.eql(u8, next, "*")) {
-                try op_stack.append(.mul);
-            } else {
-                const val = std.fmt.parseInt(u64, next, 0) catch blk: {
-                    break :blk global_vars.get(next) orelse {
-                        std.debug.print(
-                            \\
-                            \\========= Variable was not extracted: ===========
-                            \\{s}
-                            \\
-                        , .{next});
-                        return error.UnknownVariable;
-                    };
-                };
-                try values.append(val);
-            }
-        }
-
-        var op_i: usize = 1;
-        var reduced: u64 = values.items[0];
-        for (op_stack.items) |op| {
-            const other = values.items[op_i];
-            switch (op) {
-                .add => {
-                    reduced += other;
-                },
-                .sub => {
-                    reduced -= other;
-                },
-                .mod => {
-                    reduced %= other;
-                },
-                .mul => {
-                    reduced *= other;
-                },
-            }
-            op_i += 1;
-        }
-
-        const exp_value = switch (act.expected.?.value) {
-            .variable => |name| global_vars.get(name) orelse {
-                std.debug.print(
-                    \\
-                    \\========= Variable was not extracted: ===========
-                    \\{s}
-                    \\
-                , .{name});
-                return error.UnknownVariable;
-            },
-            .literal => |x| x,
-        };
-        return math.compare(reduced, act.expected.?.op, exp_value);
-    }
-};
-
-const ComputeCompareExpected = struct {
-    op: math.CompareOperator,
-    value: union(enum) {
-        variable: []const u8,
-        literal: u64,
-    },
-
-    pub fn format(
-        value: @This(),
-        comptime fmt: []const u8,
-        options: std.fmt.FormatOptions,
-        writer: anytype,
-    ) !void {
-        if (fmt.len != 0) std.fmt.invalidFmtError(fmt, value);
-        _ = options;
-        try writer.print("{s} ", .{@tagName(value.op)});
-        switch (value.value) {
-            .variable => |name| try writer.writeAll(name),
-            .literal => |x| try writer.print("{x}", .{x}),
-        }
-    }
-};
-
-const Check = struct {
-    builder: *Builder,
-    actions: std.ArrayList(Action),
-
-    fn create(b: *Builder) Check {
-        return .{
-            .builder = b,
-            .actions = std.ArrayList(Action).init(b.allocator),
-        };
-    }
-
-    fn match(self: *Check, phrase: []const u8) void {
-        self.actions.append(.{
-            .tag = .match,
-            .phrase = self.builder.dupe(phrase),
-        }) catch unreachable;
-    }
-
-    fn notPresent(self: *Check, phrase: []const u8) void {
-        self.actions.append(.{
-            .tag = .not_present,
-            .phrase = self.builder.dupe(phrase),
-        }) catch unreachable;
-    }
-
-    fn computeCmp(self: *Check, phrase: []const u8, expected: ComputeCompareExpected) void {
-        self.actions.append(.{
-            .tag = .compute_cmp,
-            .phrase = self.builder.dupe(phrase),
-            .expected = expected,
-        }) catch unreachable;
-    }
-};
-
-/// Creates a new sequence of actions with `phrase` as the first anchor searched phrase.
-pub fn checkStart(self: *CheckObjectStep, phrase: []const u8) void {
-    var new_check = Check.create(self.builder);
-    new_check.match(phrase);
-    self.checks.append(new_check) catch unreachable;
-}
-
-/// Adds another searched phrase to the latest created Check with `CheckObjectStep.checkStart(...)`.
-/// Asserts at least one check already exists.
-pub fn checkNext(self: *CheckObjectStep, phrase: []const u8) void {
-    assert(self.checks.items.len > 0);
-    const last = &self.checks.items[self.checks.items.len - 1];
-    last.match(phrase);
-}
-
-/// Adds another searched phrase to the latest created Check with `CheckObjectStep.checkStart(...)`
-/// however ensures there is no matching phrase in the output.
-/// Asserts at least one check already exists.
-pub fn checkNotPresent(self: *CheckObjectStep, phrase: []const u8) void {
-    assert(self.checks.items.len > 0);
-    const last = &self.checks.items[self.checks.items.len - 1];
-    last.notPresent(phrase);
-}
-
-/// Creates a new check checking specifically symbol table parsed and dumped from the object
-/// file.
-/// Issuing this check will force parsing and dumping of the symbol table.
-pub fn checkInSymtab(self: *CheckObjectStep) void {
-    self.dump_symtab = true;
-    const symtab_label = switch (self.obj_format) {
-        .macho => MachODumper.symtab_label,
-        else => @panic("TODO other parsers"),
-    };
-    self.checkStart(symtab_label);
-}
-
-/// Creates a new standalone, singular check which allows running simple binary operations
-/// on the extracted variables. It will then compare the reduced program with the value of
-/// the expected variable.
-pub fn checkComputeCompare(
-    self: *CheckObjectStep,
-    program: []const u8,
-    expected: ComputeCompareExpected,
-) void {
-    var new_check = Check.create(self.builder);
-    new_check.computeCmp(program, expected);
-    self.checks.append(new_check) catch unreachable;
-}
-
-fn make(step: *Step) !void {
-    const self = @fieldParentPtr(CheckObjectStep, "step", step);
-
-    const gpa = self.builder.allocator;
-    const src_path = self.source.getPath(self.builder);
-    const contents = try fs.cwd().readFileAllocOptions(
-        gpa,
-        src_path,
-        self.max_bytes,
-        null,
-        @alignOf(u64),
-        null,
-    );
-
-    const output = switch (self.obj_format) {
-        .macho => try MachODumper.parseAndDump(contents, .{
-            .gpa = gpa,
-            .dump_symtab = self.dump_symtab,
-        }),
-        .elf => @panic("TODO elf parser"),
-        .coff => @panic("TODO coff parser"),
-        .wasm => try WasmDumper.parseAndDump(contents, .{
-            .gpa = gpa,
-            .dump_symtab = self.dump_symtab,
-        }),
-        else => unreachable,
-    };
-
-    var vars = std.StringHashMap(u64).init(gpa);
-
-    for (self.checks.items) |chk| {
-        var it = mem.tokenize(u8, output, "\r\n");
-        for (chk.actions.items) |act| {
-            switch (act.tag) {
-                .match => {
-                    while (it.next()) |line| {
-                        if (try act.match(line, &vars)) break;
-                    } else {
-                        std.debug.print(
-                            \\
-                            \\========= Expected to find: ==========================
-                            \\{s}
-                            \\========= But parsed file does not contain it: =======
-                            \\{s}
-                            \\
-                        , .{ act.phrase, output });
-                        return error.TestFailed;
-                    }
-                },
-                .not_present => {
-                    while (it.next()) |line| {
-                        if (try act.match(line, &vars)) {
-                            std.debug.print(
-                                \\
-                                \\========= Expected not to find: ===================
-                                \\{s}
-                                \\========= But parsed file does contain it: ========
-                                \\{s}
-                                \\
-                            , .{ act.phrase, output });
-                            return error.TestFailed;
-                        }
-                    }
-                },
-                .compute_cmp => {
-                    const res = act.computeCmp(gpa, vars) catch |err| switch (err) {
-                        error.UnknownVariable => {
-                            std.debug.print(
-                                \\========= From parsed file: =====================
-                                \\{s}
-                                \\
-                            , .{output});
-                            return error.TestFailed;
-                        },
-                        else => |e| return e,
-                    };
-                    if (!res) {
-                        std.debug.print(
-                            \\
-                            \\========= Comparison failed for action: ===========
-                            \\{s} {}
-                            \\========= From parsed file: =======================
-                            \\{s}
-                            \\
-                        , .{ act.phrase, act.expected.?, output });
-                        return error.TestFailed;
-                    }
-                },
-            }
-        }
-    }
-}
-
-const Opts = struct {
-    gpa: ?Allocator = null,
-    dump_symtab: bool = false,
-};
-
-const MachODumper = struct {
-    const LoadCommandIterator = macho.LoadCommandIterator;
-    const symtab_label = "symtab";
-
-    fn parseAndDump(bytes: []align(@alignOf(u64)) const u8, opts: Opts) ![]const u8 {
-        const gpa = opts.gpa orelse unreachable; // MachO dumper requires an allocator
-        var stream = std.io.fixedBufferStream(bytes);
-        const reader = stream.reader();
-
-        const hdr = try reader.readStruct(macho.mach_header_64);
-        if (hdr.magic != macho.MH_MAGIC_64) {
-            return error.InvalidMagicNumber;
-        }
-
-        var output = std.ArrayList(u8).init(gpa);
-        const writer = output.writer();
-
-        var symtab: []const macho.nlist_64 = undefined;
-        var strtab: []const u8 = undefined;
-        var sections = std.ArrayList(macho.section_64).init(gpa);
-        var imports = std.ArrayList([]const u8).init(gpa);
-
-        var it = LoadCommandIterator{
-            .ncmds = hdr.ncmds,
-            .buffer = bytes[@sizeOf(macho.mach_header_64)..][0..hdr.sizeofcmds],
-        };
-        var i: usize = 0;
-        while (it.next()) |cmd| {
-            switch (cmd.cmd()) {
-                .SEGMENT_64 => {
-                    const seg = cmd.cast(macho.segment_command_64).?;
-                    try sections.ensureUnusedCapacity(seg.nsects);
-                    for (cmd.getSections()) |sect| {
-                        sections.appendAssumeCapacity(sect);
-                    }
-                },
-                .SYMTAB => if (opts.dump_symtab) {
-                    const lc = cmd.cast(macho.symtab_command).?;
-                    symtab = @ptrCast(
-                        [*]const macho.nlist_64,
-                        @alignCast(@alignOf(macho.nlist_64), &bytes[lc.symoff]),
-                    )[0..lc.nsyms];
-                    strtab = bytes[lc.stroff..][0..lc.strsize];
-                },
-                .LOAD_DYLIB,
-                .LOAD_WEAK_DYLIB,
-                .REEXPORT_DYLIB,
-                => {
-                    try imports.append(cmd.getDylibPathName());
-                },
-                else => {},
-            }
-
-            try dumpLoadCommand(cmd, i, writer);
-            try writer.writeByte('\n');
-
-            i += 1;
-        }
-
-        if (opts.dump_symtab) {
-            try writer.print("{s}\n", .{symtab_label});
-            for (symtab) |sym| {
-                if (sym.stab()) continue;
-                const sym_name = mem.sliceTo(@ptrCast([*:0]const u8, strtab.ptr + sym.n_strx), 0);
-                if (sym.sect()) {
-                    const sect = sections.items[sym.n_sect - 1];
-                    try writer.print("{x} ({s},{s})", .{
-                        sym.n_value,
-                        sect.segName(),
-                        sect.sectName(),
-                    });
-                    if (sym.ext()) {
-                        try writer.writeAll(" external");
-                    }
-                    try writer.print(" {s}\n", .{sym_name});
-                } else if (sym.undf()) {
-                    const ordinal = @divTrunc(@bitCast(i16, sym.n_desc), macho.N_SYMBOL_RESOLVER);
-                    const import_name = blk: {
-                        if (ordinal <= 0) {
-                            if (ordinal == macho.BIND_SPECIAL_DYLIB_SELF)
-                                break :blk "self import";
-                            if (ordinal == macho.BIND_SPECIAL_DYLIB_MAIN_EXECUTABLE)
-                                break :blk "main executable";
-                            if (ordinal == macho.BIND_SPECIAL_DYLIB_FLAT_LOOKUP)
-                                break :blk "flat lookup";
-                            unreachable;
-                        }
-                        const full_path = imports.items[@bitCast(u16, ordinal) - 1];
-                        const basename = fs.path.basename(full_path);
-                        assert(basename.len > 0);
-                        const ext = mem.lastIndexOfScalar(u8, basename, '.') orelse basename.len;
-                        break :blk basename[0..ext];
-                    };
-                    try writer.writeAll("(undefined)");
-                    if (sym.weakRef()) {
-                        try writer.writeAll(" weak");
-                    }
-                    if (sym.ext()) {
-                        try writer.writeAll(" external");
-                    }
-                    try writer.print(" {s} (from {s})\n", .{
-                        sym_name,
-                        import_name,
-                    });
-                } else unreachable;
-            }
-        }
-
-        return output.toOwnedSlice();
-    }
-
-    fn dumpLoadCommand(lc: macho.LoadCommandIterator.LoadCommand, index: usize, writer: anytype) !void {
-        // print header first
-        try writer.print(
-            \\LC {d}
-            \\cmd {s}
-            \\cmdsize {d}
-        , .{ index, @tagName(lc.cmd()), lc.cmdsize() });
-
-        switch (lc.cmd()) {
-            .SEGMENT_64 => {
-                const seg = lc.cast(macho.segment_command_64).?;
-                try writer.writeByte('\n');
-                try writer.print(
-                    \\segname {s}
-                    \\vmaddr {x}
-                    \\vmsize {x}
-                    \\fileoff {x}
-                    \\filesz {x}
-                , .{
-                    seg.segName(),
-                    seg.vmaddr,
-                    seg.vmsize,
-                    seg.fileoff,
-                    seg.filesize,
-                });
-
-                for (lc.getSections()) |sect| {
-                    try writer.writeByte('\n');
-                    try writer.print(
-                        \\sectname {s}
-                        \\addr {x}
-                        \\size {x}
-                        \\offset {x}
-                        \\align {x}
-                    , .{
-                        sect.sectName(),
-                        sect.addr,
-                        sect.size,
-                        sect.offset,
-                        sect.@"align",
-                    });
-                }
-            },
-
-            .ID_DYLIB,
-            .LOAD_DYLIB,
-            .LOAD_WEAK_DYLIB,
-            .REEXPORT_DYLIB,
-            => {
-                const dylib = lc.cast(macho.dylib_command).?;
-                try writer.writeByte('\n');
-                try writer.print(
-                    \\name {s}
-                    \\timestamp {d}
-                    \\current version {x}
-                    \\compatibility version {x}
-                , .{
-                    lc.getDylibPathName(),
-                    dylib.dylib.timestamp,
-                    dylib.dylib.current_version,
-                    dylib.dylib.compatibility_version,
-                });
-            },
-
-            .MAIN => {
-                const main = lc.cast(macho.entry_point_command).?;
-                try writer.writeByte('\n');
-                try writer.print(
-                    \\entryoff {x}
-                    \\stacksize {x}
-                , .{ main.entryoff, main.stacksize });
-            },
-
-            .RPATH => {
-                try writer.writeByte('\n');
-                try writer.print(
-                    \\path {s}
-                , .{
-                    lc.getRpathPathName(),
-                });
-            },
-
-            .UUID => {
-                const uuid = lc.cast(macho.uuid_command).?;
-                try writer.writeByte('\n');
-                try writer.print("uuid {x}", .{std.fmt.fmtSliceHexLower(&uuid.uuid)});
-            },
-
-            .DATA_IN_CODE,
-            .FUNCTION_STARTS,
-            .CODE_SIGNATURE,
-            => {
-                const llc = lc.cast(macho.linkedit_data_command).?;
-                try writer.writeByte('\n');
-                try writer.print(
-                    \\dataoff {x}
-                    \\datasize {x}
-                , .{ llc.dataoff, llc.datasize });
-            },
-
-            .DYLD_INFO_ONLY => {
-                const dlc = lc.cast(macho.dyld_info_command).?;
-                try writer.writeByte('\n');
-                try writer.print(
-                    \\rebaseoff {x}
-                    \\rebasesize {x}
-                    \\bindoff {x}
-                    \\bindsize {x}
-                    \\weakbindoff {x}
-                    \\weakbindsize {x}
-                    \\lazybindoff {x}
-                    \\lazybindsize {x}
-                    \\exportoff {x}
-                    \\exportsize {x}
-                , .{
-                    dlc.rebase_off,
-                    dlc.rebase_size,
-                    dlc.bind_off,
-                    dlc.bind_size,
-                    dlc.weak_bind_off,
-                    dlc.weak_bind_size,
-                    dlc.lazy_bind_off,
-                    dlc.lazy_bind_size,
-                    dlc.export_off,
-                    dlc.export_size,
-                });
-            },
-
-            .SYMTAB => {
-                const slc = lc.cast(macho.symtab_command).?;
-                try writer.writeByte('\n');
-                try writer.print(
-                    \\symoff {x}
-                    \\nsyms {x}
-                    \\stroff {x}
-                    \\strsize {x}
-                , .{
-                    slc.symoff,
-                    slc.nsyms,
-                    slc.stroff,
-                    slc.strsize,
-                });
-            },
-
-            .DYSYMTAB => {
-                const dlc = lc.cast(macho.dysymtab_command).?;
-                try writer.writeByte('\n');
-                try writer.print(
-                    \\ilocalsym {x}
-                    \\nlocalsym {x}
-                    \\iextdefsym {x}
-                    \\nextdefsym {x}
-                    \\iundefsym {x}
-                    \\nundefsym {x}
-                    \\indirectsymoff {x}
-                    \\nindirectsyms {x}
-                , .{
-                    dlc.ilocalsym,
-                    dlc.nlocalsym,
-                    dlc.iextdefsym,
-                    dlc.nextdefsym,
-                    dlc.iundefsym,
-                    dlc.nundefsym,
-                    dlc.indirectsymoff,
-                    dlc.nindirectsyms,
-                });
-            },
-
-            else => {},
-        }
-    }
-};
-
-const WasmDumper = struct {
-    const symtab_label = "symbols";
-
-    fn parseAndDump(bytes: []const u8, opts: Opts) ![]const u8 {
-        const gpa = opts.gpa orelse unreachable; // Wasm dumper requires an allocator
-        if (opts.dump_symtab) {
-            @panic("TODO: Implement symbol table parsing and dumping");
-        }
-
-        var fbs = std.io.fixedBufferStream(bytes);
-        const reader = fbs.reader();
-
-        const buf = try reader.readBytesNoEof(8);
-        if (!mem.eql(u8, buf[0..4], &std.wasm.magic)) {
-            return error.InvalidMagicByte;
-        }
-        if (!mem.eql(u8, buf[4..], &std.wasm.version)) {
-            return error.UnsupportedWasmVersion;
-        }
-
-        var output = std.ArrayList(u8).init(gpa);
-        errdefer output.deinit();
-        const writer = output.writer();
-
-        while (reader.readByte()) |current_byte| {
-            const section = std.meta.intToEnum(std.wasm.Section, current_byte) catch |err| {
-                std.debug.print("Found invalid section id '{d}'\n", .{current_byte});
-                return err;
-            };
-
-            const section_length = try std.leb.readULEB128(u32, reader);
-            try parseAndDumpSection(section, bytes[fbs.pos..][0..section_length], writer);
-            fbs.pos += section_length;
-        } else |_| {} // reached end of stream
-
-        return output.toOwnedSlice();
-    }
-
-    fn parseAndDumpSection(section: std.wasm.Section, data: []const u8, writer: anytype) !void {
-        var fbs = std.io.fixedBufferStream(data);
-        const reader = fbs.reader();
-
-        try writer.print(
-            \\Section {s}
-            \\size {d}
-        , .{ @tagName(section), data.len });
-
-        switch (section) {
-            .type,
-            .import,
-            .function,
-            .table,
-            .memory,
-            .global,
-            .@"export",
-            .element,
-            .code,
-            .data,
-            => {
-                const entries = try std.leb.readULEB128(u32, reader);
-                try writer.print("\nentries {d}\n", .{entries});
-                try dumpSection(section, data[fbs.pos..], entries, writer);
-            },
-            .custom => {
-                const name_length = try std.leb.readULEB128(u32, reader);
-                const name = data[fbs.pos..][0..name_length];
-                fbs.pos += name_length;
-                try writer.print("\nname {s}\n", .{name});
-
-                if (mem.eql(u8, name, "name")) {
-                    try parseDumpNames(reader, writer, data);
-                } else if (mem.eql(u8, name, "producers")) {
-                    try parseDumpProducers(reader, writer, data);
-                } else if (mem.eql(u8, name, "target_features")) {
-                    try parseDumpFeatures(reader, writer, data);
-                }
-                // TODO: Implement parsing and dumping other custom sections (such as relocations)
-            },
-            .start => {
-                const start = try std.leb.readULEB128(u32, reader);
-                try writer.print("\nstart {d}\n", .{start});
-            },
-            else => {}, // skip unknown sections
-        }
-    }
-
-    fn dumpSection(section: std.wasm.Section, data: []const u8, entries: u32, writer: anytype) !void {
-        var fbs = std.io.fixedBufferStream(data);
-        const reader = fbs.reader();
-
-        switch (section) {
-            .type => {
-                var i: u32 = 0;
-                while (i < entries) : (i += 1) {
-                    const func_type = try reader.readByte();
-                    if (func_type != std.wasm.function_type) {
-                        std.debug.print("Expected function type, found byte '{d}'\n", .{func_type});
-                        return error.UnexpectedByte;
-                    }
-                    const params = try std.leb.readULEB128(u32, reader);
-                    try writer.print("params {d}\n", .{params});
-                    var index: u32 = 0;
-                    while (index < params) : (index += 1) {
-                        try parseDumpType(std.wasm.Valtype, reader, writer);
-                    } else index = 0;
-                    const returns = try std.leb.readULEB128(u32, reader);
-                    try writer.print("returns {d}\n", .{returns});
-                    while (index < returns) : (index += 1) {
-                        try parseDumpType(std.wasm.Valtype, reader, writer);
-                    }
-                }
-            },
-            .import => {
-                var i: u32 = 0;
-                while (i < entries) : (i += 1) {
-                    const module_name_len = try std.leb.readULEB128(u32, reader);
-                    const module_name = data[fbs.pos..][0..module_name_len];
-                    fbs.pos += module_name_len;
-                    const name_len = try std.leb.readULEB128(u32, reader);
-                    const name = data[fbs.pos..][0..name_len];
-                    fbs.pos += name_len;
-
-                    const kind = std.meta.intToEnum(std.wasm.ExternalKind, try reader.readByte()) catch |err| {
-                        std.debug.print("Invalid import kind\n", .{});
-                        return err;
-                    };
-
-                    try writer.print(
-                        \\module {s}
-                        \\name {s}
-                        \\kind {s}
-                    , .{ module_name, name, @tagName(kind) });
-                    try writer.writeByte('\n');
-                    switch (kind) {
-                        .function => {
-                            try writer.print("index {d}\n", .{try std.leb.readULEB128(u32, reader)});
-                        },
-                        .memory => {
-                            try parseDumpLimits(reader, writer);
-                        },
-                        .global => {
-                            try parseDumpType(std.wasm.Valtype, reader, writer);
-                            try writer.print("mutable {}\n", .{0x01 == try std.leb.readULEB128(u32, reader)});
-                        },
-                        .table => {
-                            try parseDumpType(std.wasm.RefType, reader, writer);
-                            try parseDumpLimits(reader, writer);
-                        },
-                    }
-                }
-            },
-            .function => {
-                var i: u32 = 0;
-                while (i < entries) : (i += 1) {
-                    try writer.print("index {d}\n", .{try std.leb.readULEB128(u32, reader)});
-                }
-            },
-            .table => {
-                var i: u32 = 0;
-                while (i < entries) : (i += 1) {
-                    try parseDumpType(std.wasm.RefType, reader, writer);
-                    try parseDumpLimits(reader, writer);
-                }
-            },
-            .memory => {
-                var i: u32 = 0;
-                while (i < entries) : (i += 1) {
-                    try parseDumpLimits(reader, writer);
-                }
-            },
-            .global => {
-                var i: u32 = 0;
-                while (i < entries) : (i += 1) {
-                    try parseDumpType(std.wasm.Valtype, reader, writer);
-                    try writer.print("mutable {}\n", .{0x01 == try std.leb.readULEB128(u1, reader)});
-                    try parseDumpInit(reader, writer);
-                }
-            },
-            .@"export" => {
-                var i: u32 = 0;
-                while (i < entries) : (i += 1) {
-                    const name_len = try std.leb.readULEB128(u32, reader);
-                    const name = data[fbs.pos..][0..name_len];
-                    fbs.pos += name_len;
-                    const kind_byte = try std.leb.readULEB128(u8, reader);
-                    const kind = std.meta.intToEnum(std.wasm.ExternalKind, kind_byte) catch |err| {
-                        std.debug.print("invalid export kind value '{d}'\n", .{kind_byte});
-                        return err;
-                    };
-                    const index = try std.leb.readULEB128(u32, reader);
-                    try writer.print(
-                        \\name {s}
-                        \\kind {s}
-                        \\index {d}
-                    , .{ name, @tagName(kind), index });
-                    try writer.writeByte('\n');
-                }
-            },
-            .element => {
-                var i: u32 = 0;
-                while (i < entries) : (i += 1) {
-                    try writer.print("table index {d}\n", .{try std.leb.readULEB128(u32, reader)});
-                    try parseDumpInit(reader, writer);
-
-                    const function_indexes = try std.leb.readULEB128(u32, reader);
-                    var function_index: u32 = 0;
-                    try writer.print("indexes {d}\n", .{function_indexes});
-                    while (function_index < function_indexes) : (function_index += 1) {
-                        try writer.print("index {d}\n", .{try std.leb.readULEB128(u32, reader)});
-                    }
-                }
-            },
-            .code => {}, // code section is considered opaque to linker
-            .data => {
-                var i: u32 = 0;
-                while (i < entries) : (i += 1) {
-                    const index = try std.leb.readULEB128(u32, reader);
-                    try writer.print("memory index 0x{x}\n", .{index});
-                    try parseDumpInit(reader, writer);
-                    const size = try std.leb.readULEB128(u32, reader);
-                    try writer.print("size {d}\n", .{size});
-                    try reader.skipBytes(size, .{}); // we do not care about the content of the segments
-                }
-            },
-            else => unreachable,
-        }
-    }
-
-    fn parseDumpType(comptime WasmType: type, reader: anytype, writer: anytype) !void {
-        const type_byte = try reader.readByte();
-        const valtype = std.meta.intToEnum(WasmType, type_byte) catch |err| {
-            std.debug.print("Invalid wasm type value '{d}'\n", .{type_byte});
-            return err;
-        };
-        try writer.print("type {s}\n", .{@tagName(valtype)});
-    }
-
-    fn parseDumpLimits(reader: anytype, writer: anytype) !void {
-        const flags = try std.leb.readULEB128(u8, reader);
-        const min = try std.leb.readULEB128(u32, reader);
-
-        try writer.print("min {x}\n", .{min});
-        if (flags != 0) {
-            try writer.print("max {x}\n", .{try std.leb.readULEB128(u32, reader)});
-        }
-    }
-
-    fn parseDumpInit(reader: anytype, writer: anytype) !void {
-        const byte = try std.leb.readULEB128(u8, reader);
-        const opcode = std.meta.intToEnum(std.wasm.Opcode, byte) catch |err| {
-            std.debug.print("invalid wasm opcode '{d}'\n", .{byte});
-            return err;
-        };
-        switch (opcode) {
-            .i32_const => try writer.print("i32.const {x}\n", .{try std.leb.readILEB128(i32, reader)}),
-            .i64_const => try writer.print("i64.const {x}\n", .{try std.leb.readILEB128(i64, reader)}),
-            .f32_const => try writer.print("f32.const {x}\n", .{@bitCast(f32, try reader.readIntLittle(u32))}),
-            .f64_const => try writer.print("f64.const {x}\n", .{@bitCast(f64, try reader.readIntLittle(u64))}),
-            .global_get => try writer.print("global.get {x}\n", .{try std.leb.readULEB128(u32, reader)}),
-            else => unreachable,
-        }
-        const end_opcode = try std.leb.readULEB128(u8, reader);
-        if (end_opcode != std.wasm.opcode(.end)) {
-            std.debug.print("expected 'end' opcode in init expression\n", .{});
-            return error.MissingEndOpcode;
-        }
-    }
-
-    fn parseDumpNames(reader: anytype, writer: anytype, data: []const u8) !void {
-        while (reader.context.pos < data.len) {
-            try parseDumpType(std.wasm.NameSubsection, reader, writer);
-            const size = try std.leb.readULEB128(u32, reader);
-            const entries = try std.leb.readULEB128(u32, reader);
-            try writer.print(
-                \\size {d}
-                \\names {d}
-            , .{ size, entries });
-            try writer.writeByte('\n');
-            var i: u32 = 0;
-            while (i < entries) : (i += 1) {
-                const index = try std.leb.readULEB128(u32, reader);
-                const name_len = try std.leb.readULEB128(u32, reader);
-                const pos = reader.context.pos;
-                const name = data[pos..][0..name_len];
-                reader.context.pos += name_len;
-
-                try writer.print(
-                    \\index {d}
-                    \\name {s}
-                , .{ index, name });
-                try writer.writeByte('\n');
-            }
-        }
-    }
-
-    fn parseDumpProducers(reader: anytype, writer: anytype, data: []const u8) !void {
-        const field_count = try std.leb.readULEB128(u32, reader);
-        try writer.print("fields {d}\n", .{field_count});
-        var current_field: u32 = 0;
-        while (current_field < field_count) : (current_field += 1) {
-            const field_name_length = try std.leb.readULEB128(u32, reader);
-            const field_name = data[reader.context.pos..][0..field_name_length];
-            reader.context.pos += field_name_length;
-
-            const value_count = try std.leb.readULEB128(u32, reader);
-            try writer.print(
-                \\field_name {s}
-                \\values {d}
-            , .{ field_name, value_count });
-            try writer.writeByte('\n');
-            var current_value: u32 = 0;
-            while (current_value < value_count) : (current_value += 1) {
-                const value_length = try std.leb.readULEB128(u32, reader);
-                const value = data[reader.context.pos..][0..value_length];
-                reader.context.pos += value_length;
-
-                const version_length = try std.leb.readULEB128(u32, reader);
-                const version = data[reader.context.pos..][0..version_length];
-                reader.context.pos += version_length;
-
-                try writer.print(
-                    \\value_name {s}
-                    \\version {s}
-                , .{ value, version });
-                try writer.writeByte('\n');
-            }
-        }
-    }
-
-    fn parseDumpFeatures(reader: anytype, writer: anytype, data: []const u8) !void {
-        const feature_count = try std.leb.readULEB128(u32, reader);
-        try writer.print("features {d}\n", .{feature_count});
-
-        var index: u32 = 0;
-        while (index < feature_count) : (index += 1) {
-            const prefix_byte = try std.leb.readULEB128(u8, reader);
-            const name_length = try std.leb.readULEB128(u32, reader);
-            const feature_name = data[reader.context.pos..][0..name_length];
-            reader.context.pos += name_length;
-
-            try writer.print("{c} {s}\n", .{ prefix_byte, feature_name });
-        }
-    }
-};