Got a working test connecting to postgres server and reading data.

Added a couple more message types to facilitate this.

1 files changed, 64 insertions, 0 deletions

diff --git a/src/parameter_status.zig b/src/parameter_status.zig
new file mode 100644
index 0000000..d938fd2
--- /dev/null
+++ b/src/parameter_status.zig
@@ -0,0 +1,64 @@
+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 ParameterStatus = @This();
+pub const Tag: u8 = 'S';
+
+buf: ?[]const u8 = null, // owned
+name: []const u8,
+value: []const u8,
+
+pub fn read(allocator: std.mem.Allocator, b: []const u8) !ParameterStatus {
+    var res: ParameterStatus = undefined;
+    res.buf = try allocator.dupe(u8, b);
+    var it = std.mem.splitScalar(u8, res.buf.?, 0);
+    res.name = it.first();
+    res.value = it.next() orelse return ProtocolError.MissingField;
+    return res;
+}
+pub fn write(self: ParameterStatus, a: std.mem.Allocator, stream_writer: anytype) !void {
+    try stream_writer.writeByte(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.writeAll(self.name);
+    try writer.writeByte(0);
+    try writer.writeAll(self.value);
+    try writer.writeByte(0);
+    std.mem.writeIntBig(u32, al.items[0..4], @as(u32,@intCast(cw.bytes_written))); // Fix length
+    try stream_writer.writeAll(al.items);
+}
+pub fn deinit(self: *ParameterStatus, allocator: std.mem.Allocator) void {
+    if (self.buf != null) allocator.free(self.buf.?);
+}
+
+test "round trip" {
+    const allocator = std.testing.allocator;
+    var sm = ParameterStatus{
+        .name = "Hello",
+        .value = "world",
+    };
+    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);
+    defer allocator.free(buf);
+    try reader.readNoEof(buf);
+    var sm2 = try ParameterStatus.read(allocator, buf);
+    defer sm2.deinit(allocator);
+    try std.testing.expectEqualStrings("Hello", sm2.name);
+    try std.testing.expectEqualStrings("world", sm2.value);
+}