tmp: implement target description

This commit is contained in:
Rekai Nyangadzayi Musuka 2022-12-11 01:06:29 -04:00
parent fa21af5fb6
commit 3ba7f22c07
1 changed files with 77 additions and 14 deletions

View File

@ -6,6 +6,32 @@ const Socket = network.Socket;
const port: u16 = 2424;
const target: []const u8 =
\\<target version="1.0">
\\ <architecture>armv4t</architecture>
\\ <feature name="org.gnu.gdb.arm.core">
\\ <reg name="r0" bitsize="32" type="uint32"/>
\\ <reg name="r1" bitsize="32" type="uint32"/>
\\ <reg name="r2" bitsize="32" type="uint32"/>
\\ <reg name="r3" bitsize="32" type="uint32"/>
\\ <reg name="r4" bitsize="32" type="uint32"/>
\\ <reg name="r5" bitsize="32" type="uint32"/>
\\ <reg name="r6" bitsize="32" type="uint32"/>
\\ <reg name="r7" bitsize="32" type="uint32"/>
\\ <reg name="r8" bitsize="32" type="uint32"/>
\\ <reg name="r9" bitsize="32" type="uint32"/>
\\ <reg name="r10" bitsize="32" type="uint32"/>
\\ <reg name="r11" bitsize="32" type="uint32"/>
\\ <reg name="r12" bitsize="32" type="uint32"/>
\\ <reg name="sp" bitsize="32" type="data_ptr"/>
\\ <reg name="lr" bitsize="32"/>
\\ <reg name="pc" bitsize="32" type="code_ptr"/>
\\
\\ <reg name="cpsr" bitsize="32" regnum="25"/>
\\ </feature>
\\</target>
;
pub fn main() !void {
const log = std.log.scoped(.Server);
@ -48,35 +74,35 @@ fn gdbStubServer(allocator: Allocator, client: Socket) !void {
if (previous) |packet| allocator.free(packet);
previous = response;
},
.recognize_ack => {
.recv_ack => {
if (previous) |packet| allocator.free(packet);
previous = null;
},
.retry => {},
.recv_nack => {},
}
}
}
const Action = union(enum) {
send: []const u8,
retry,
recognize_ack,
recv_nack,
recv_ack,
};
fn parse(allocator: Allocator, client: Socket, previous: ?[]const u8, input: []const u8) !Action {
const log = std.log.scoped(.GdbStubParser);
return switch (input[0]) {
'+' => .recognize_ack,
'+' => .recv_ack,
'-' => blk: {
if (previous) |packet| {
log.warn("Received negative ack, resending: \"{s}\"", .{packet});
log.warn("received nack, resending: \"{s}\"", .{packet});
_ = try client.send(packet);
} else {
log.err("Server sent negative ack, but gdbstub doesn't recall sending anything", .{});
log.err("received nack, but we don't recall sending anything", .{});
}
break :blk .retry;
break :blk .recv_nack;
},
'$' => blk: {
// Packet
@ -149,7 +175,7 @@ const Packet = struct {
const ret: Signal = .Trap;
// Deallocated by the caller
return .{ .alloc = try std.fmt.allocPrint(allocator, "S {x:0>2}", .{@enumToInt(ret)}) };
return .{ .alloc = try std.fmt.allocPrint(allocator, "T{x:0>2}thread:1;", .{@enumToInt(ret)}) };
},
'g', 'G' => @panic("TODO: Register Access"),
'm', 'M' => @panic("TODO: Memory Access"),
@ -177,13 +203,50 @@ const Packet = struct {
return .{ .static = "" };
},
'q' => {
if (substr(self.contents[1..], "Supported")) {
const ret = try std.fmt.allocPrint(allocator, "PacketSize={x:}", .{Packet.size});
// TODO: Should we support anything else?
if (self.contents[1] == 'C' and self.contents.len == 2) return .{ .static = "QC1" };
if (substr(self.contents[1..], "fThreadInfo")) return .{ .static = "m1" };
if (substr(self.contents[1..], "sThreadInfo")) return .{ .static = "l" };
if (substr(self.contents[1..], "Attached")) return .{ .static = "1" }; // Tell GDB we're attached to a process
if (substr(self.contents[1..], "Supported")) {
const format = "PacketSize={x:};qXfer:features:read+;qXfer:memory-map:read+";
// TODO: Anything else?
const ret = try std.fmt.allocPrint(allocator, format, .{Packet.size});
return .{ .alloc = ret };
} else if (substr(self.contents[1..], "Attached")) {
return .{ .static = "0" }; // We tell GDB that we've created a new process
}
if (substr(self.contents[1..], "Xfer:features:read")) {
var tokens = std.mem.tokenize(u8, self.contents[1..], ":,");
_ = tokens.next(); // qXfer
_ = tokens.next(); // features
_ = tokens.next(); // read
const annex = tokens.next() orelse return .{ .static = "E00" };
const offset_str = tokens.next() orelse return .{ .static = "E00" };
const length_str = tokens.next() orelse return .{ .static = "E00" };
if (std.mem.eql(u8, annex, "target.xml")) {
log.info("Providing ARMv4T target description", .{});
const offset = try std.fmt.parseInt(usize, offset_str, 16);
const length = try std.fmt.parseInt(usize, length_str, 16);
// + 2 to account for the "m " in the response
// subtract offset so that the allocated buffer isn't
// larger than it needs to be TODO: Test this?
const len = @min(length, (target.len + 1) - offset);
const ret = try allocator.alloc(u8, len);
ret[0] = if (ret.len < length) 'l' else 'm';
std.mem.copy(u8, ret[1..], target[offset..]);
return .{ .alloc = ret };
} else {
log.err("Unexpected Annex: {s}", .{annex});
return .{ .static = "E00" };
}
return .{ .static = "" };
}
log.warn("Unimplemented: {s}", .{self.contents});