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const std = @import("std");
const log = std.log.scoped(.pgz);
const ByteArrayList = std.ArrayList(u8);
const ProtocolError = @import("../main.zig").ProtocolError;
const ClientError = @import("../main.zig").ClientError;
const enum_from_int = @import("../main.zig").enum_from_int;
const FormatCode = @import("../main.zig").FormatCode;
pub fn CopyXResponse(comptime tag: u8) type {
return struct {
pub const Tag: u8 = tag;
overall_format_code: u8,
format_codes: []const FormatCode, // owned
pub fn read(a: std.mem.Allocator, buf: []const u8) !@This() {
defer a.free(buf);
var fbs = std.io.fixedBufferStream(buf);
var reader = fbs.reader();
const overall_format_code = try reader.readIntBig(u8);
const n_columns = try reader.readIntBig(u16);
var format_codes = try a.alloc(FormatCode, n_columns);
errdefer a.free(format_codes);
for (0..n_columns) |i| {
const int_format_code = try reader.readIntBig(u16);
format_codes[i] = enum_from_int(FormatCode, int_format_code) orelse return ProtocolError.InvalidFormatCode;
}
return .{
.overall_format_code = overall_format_code,
.format_codes = format_codes,
};
}
pub fn write(self: @This(), a: std.mem.Allocator, stream_writer: anytype) !void {
try stream_writer.writeIntBig(u8, Tag);
var al = ByteArrayList.init(a);
defer al.deinit();
var cw = std.io.countingWriter(al.writer());
var writer = cw.writer();
try writer.writeIntBig(u32, 0); // length placeholder
try writer.writeIntBig(u8, self.overall_format_code);
try writer.writeIntBig(u16, @intCast(self.format_codes.len));
for (self.format_codes) |format_code| {
try writer.writeIntBig(u16, @intFromEnum(format_code));
}
std.mem.writeIntBig(u32, al.items[0..4], @as(u32, @intCast(cw.bytes_written))); // Update length
try stream_writer.writeAll(al.items);
}
pub fn deinit(self: *@This(), a: std.mem.Allocator) void {
a.free(self.format_codes);
}
};
}
test "round trip" {
const Tag: u8 = 'G';
const CopyInResponse = CopyXResponse(Tag);
const allocator = std.testing.allocator;
var format_codes = try allocator.alloc(FormatCode, 3);
format_codes[0] = .Binary;
format_codes[1] = .Binary;
format_codes[2] = .Text;
var sm = CopyInResponse{
.overall_format_code = 1,
.format_codes = format_codes,
};
defer sm.deinit(allocator);
var bal = ByteArrayList.init(allocator);
defer bal.deinit();
try sm.write(allocator, bal.writer());
var fbs = std.io.fixedBufferStream(bal.items);
var reader = fbs.reader();
const tag = try reader.readByte();
try std.testing.expectEqual(Tag, tag);
const len = try reader.readIntBig(u32);
const buf = try allocator.alloc(u8, len - 4);
try reader.readNoEof(buf);
var sm2 = try CopyInResponse.read(allocator, buf);
defer sm2.deinit(allocator);
try std.testing.expectEqual(FormatCode.Binary, sm2.format_codes[0]);
try std.testing.expectEqual(FormatCode.Binary, sm2.format_codes[1]);
try std.testing.expectEqual(FormatCode.Text, sm2.format_codes[2]);
}
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