Merge branch 'lukeshu/misc'

5 files changed, 67 insertions, 29 deletions

diff --git a/lib9p/9p.c b/lib9p/9p.c
index 51ff2eb..c54dae7 100644
--- a/lib9p/9p.c
+++ b/lib9p/9p.c
@@ -124,10 +124,12 @@ ssize_t _lib9p_validate(uint8_t                          xxx_low_typ_bit,
                         struct lib9p_ctx *ctx, uint8_t *net_bytes) {
 	/* Inspect the first 5 bytes ourselves.  */
 	struct _validate_ctx subctx = {
+		/* input */
 		.ctx        = ctx,
 		.net_size   = uint32le_decode(net_bytes),
 		.net_bytes  = net_bytes,
 
+		/* output */
 		.net_offset = 0,
 		.host_extra = 0,
 	};
@@ -171,17 +173,19 @@ static
 void _lib9p_unmarshal(const struct _lib9p_recv_tentry xxx_table[LIB9P_VER_NUM][0x80],
                       struct lib9p_ctx *ctx, uint8_t *net_bytes,
                       enum lib9p_msg_type *ret_typ, void *ret_body) {
+	enum lib9p_msg_type typ = net_bytes[4];
+	*ret_typ = typ;
+	struct _lib9p_recv_tentry tentry = xxx_table[ctx->version][typ/2];
+
 	struct _unmarshal_ctx subctx = {
+		/* input */
 		.ctx        = ctx,
 		.net_bytes  = net_bytes,
 
+		/* output */
 		.net_offset = 0,
+		.extra      = ret_body + tentry.basesize,
 	};
-
-	enum lib9p_msg_type typ = net_bytes[4];
-	*ret_typ = typ;
-	struct _lib9p_recv_tentry tentry = xxx_table[ctx->version][typ/2];
-	subctx.extra = ret_body + tentry.basesize;
 	tentry.unmarshal(&subctx, ret_body);
 }
 
@@ -202,7 +206,10 @@ bool _lib9p_marshal(const struct _lib9p_send_tentry xxx_table[LIB9P_VER_NUM][0x8
                     struct lib9p_ctx *ctx, enum lib9p_msg_type typ, void *body,
                     uint8_t *ret_bytes) {
 	struct _marshal_ctx subctx = {
+		/* input */
 		.ctx        = ctx,
+
+		/* ouptut */
 		.net_bytes  = ret_bytes,
 		.net_offset = 0,
 	};
@@ -228,10 +235,12 @@ bool lib9p_Rmsg_marshal(struct lib9p_ctx *ctx, enum lib9p_msg_type typ, void *bo
 bool lib9p_stat_validate(struct lib9p_ctx *ctx, uint32_t net_size, uint8_t *net_bytes,
                          uint32_t *ret_net_size, ssize_t *ret_host_size) {
 	struct _validate_ctx subctx = {
+		/* input */
 		.ctx        = ctx,
 		.net_size   = net_size,
 		.net_bytes  = net_bytes,
 
+		/* output */
 		.net_offset = 0,
 		.host_extra = 0,
 	};
@@ -248,11 +257,13 @@ bool lib9p_stat_validate(struct lib9p_ctx *ctx, uint32_t net_size, uint8_t *net_
 uint32_t lib9p_stat_unmarshal(struct lib9p_ctx *ctx, uint8_t *net_bytes,
                               struct lib9p_stat *ret_obj, void *ret_extra) {
 	struct _unmarshal_ctx subctx = {
-		.ctx = ctx,
-		.net_bytes = net_bytes,
-		.net_offset = 0,
+		/* input */
+		.ctx        = ctx,
+		.net_bytes  = net_bytes,
 
-		.extra = ret_extra,
+		/* output */
+		.net_offset = 0,
+		.extra      = ret_extra,
 	};
 	_lib9p_stat_unmarshal(&subctx, ret_obj);
 	return subctx.net_offset;
@@ -263,7 +274,10 @@ uint32_t lib9p_stat_marshal(struct lib9p_ctx *ctx, uint32_t max_net_size, struct
 	struct lib9p_ctx _ctx = *ctx;
 	_ctx.max_msg_size = max_net_size;
 	struct _marshal_ctx subctx = {
+		/* input */
 		.ctx        = &_ctx,
+
+		/* output */
 		.net_bytes  = ret_bytes,
 		.net_offset = 0,
 	};
diff --git a/lib9p/idl.gen b/lib9p/idl.gen
index 8782771..adb15ce 100755
--- a/lib9p/idl.gen
+++ b/lib9p/idl.gen
@@ -53,13 +53,13 @@ def c_ver_enum(ver: str) -> str:
     return f"{idprefix.upper()}VER_{ver.replace('.', '_')}"
 
 
-def c_ver_ifdef(versions: set[str]) -> str:
+def c_ver_ifdef(versions: typing.Collection[str]) -> str:
     return " || ".join(
         f"CONFIG_9P_ENABLE_{v.replace('.', '_')}" for v in sorted(versions)
     )
 
 
-def c_ver_cond(versions: set[str]) -> str:
+def c_ver_cond(versions: typing.Collection[str]) -> str:
     if len(versions) == 1:
         v = next(v for v in versions)
         return f"is_ver(ctx, {v.replace('.', '_')})"
@@ -84,7 +84,7 @@ def c_typename(typ: idl.Type, parent: idl.StructMember | None = None) -> str:
             raise ValueError(f"not a type: {typ.__class__.__name__}")
 
 
-def c_expr(expr: idl.Expr) -> str:
+def c_expr(expr: idl.Expr, lookup_sym: typing.Callable[[str], str]) -> str:
     ret: list[str] = []
     for tok in expr.tokens:
         match tok:
@@ -92,14 +92,14 @@ def c_expr(expr: idl.Expr) -> str:
                 ret.append(tok.op)
             case idl.ExprLit():
                 ret.append(str(tok.val))
-            case idl.ExprSym(name="end"):
-                ret.append("ctx->net_offset")
             case idl.ExprSym(name="s32_max"):
                 ret.append("INT32_MAX")
             case idl.ExprSym(name="s64_max"):
                 ret.append("INT64_MAX")
             case idl.ExprSym():
-                ret.append(f"_{tok.name[1:]}_offset")
+                ret.append(lookup_sym(tok.name))
+            case _:
+                assert False
     return " ".join(ret)
 
 
@@ -411,7 +411,7 @@ def gen_c(versions: set[str], typs: list[idl.Type]) -> str:
     ret += f"""
 /* strings ********************************************************************/
 
-const char *_lib9p_table_ver_name[{c_ver_enum('NUM')}] = {{
+const char *_{idprefix}table_ver_name[{c_ver_enum('NUM')}] = {{
 """
     for ver in ["unknown", *sorted(versions)]:
         if ver in versions:
@@ -573,17 +573,26 @@ LM_ALWAYS_INLINE static bool validate_8(struct _validate_ctx *ctx) { return _val
 
                 # Pass 4 - validate ,max= and ,val= constraints
                 for member in typ.members:
+
+                    def lookup_sym(sym: str) -> str:
+                        match sym:
+                            case "end":
+                                return "ctx->net_offset"
+                            case _:
+                                assert sym.startswith("&")
+                                return f"_{sym[1:]}_offset"
+
                     if member.max:
                         assert member.static_size
                         nbits = member.static_size * 8
                         ret += ifdef_push(2, c_ver_ifdef(member.in_versions))
-                        ret += f"\t    || ({{ uint{nbits}_t max = {c_expr(member.max)}; (((uint{nbits}_t){member.name}) > max) &&\n"
+                        ret += f"\t    || ({{ uint{nbits}_t max = {c_expr(member.max, lookup_sym)}; (((uint{nbits}_t){member.name}) > max) &&\n"
                         ret += f'\t          lib9p_errorf(ctx->ctx, LINUX_EBADMSG, "{member.name} value is too large (%"PRIu{nbits}" > %"PRIu{nbits}")", {member.name}, max); }})\n'
                     if member.val:
                         assert member.static_size
                         nbits = member.static_size * 8
                         ret += ifdef_push(2, c_ver_ifdef(member.in_versions))
-                        ret += f"\t    || ({{ uint{nbits}_t exp = {c_expr(member.val)}; (((uint{nbits}_t){member.name}) != exp) &&\n"
+                        ret += f"\t    || ({{ uint{nbits}_t exp = {c_expr(member.val, lookup_sym)}; (((uint{nbits}_t){member.name}) != exp) &&\n"
                         ret += f'\t          lib9p_errorf(ctx->ctx, LINUX_EBADMSG, "{member.name} value is wrong (actual:%"PRIu{nbits}" != correct:%"PRIu{nbits}")", (uint{nbits}_t){member.name}, exp); }})\n'
 
                 ret += ifdef_pop(1)
@@ -775,10 +784,19 @@ LM_ALWAYS_INLINE static bool marshal_8(struct _marshal_ctx *ctx, uint64_t *val)
                     if member.val:
                         assert member.static_size
                         ret += ifdef_push(2, c_ver_ifdef(member.in_versions))
+
+                        def lookup_sym(sym: str) -> str:
+                            match sym:
+                                case "end":
+                                    return "ctx->net_offset"
+                                case _:
+                                    assert sym.startswith("&")
+                                    return f"_{sym[1:]}_offset"
+
                         if member.static_size == 1:
-                            ret += f"\t    || ({{ ctx->net_bytes[_{member.name}_offset] = {c_expr(member.val)}; false; }})\n"
+                            ret += f"\t    || ({{ ctx->net_bytes[_{member.name}_offset] = {c_expr(member.val, lookup_sym)}; false; }})\n"
                         else:
-                            ret += f"\t    || ({{ uint{member.static_size*8}le_encode(&ctx->net_bytes[_{member.name}_offset], {c_expr(member.val)}); false; }})\n"
+                            ret += f"\t    || ({{ uint{member.static_size*8}le_encode(&ctx->net_bytes[_{member.name}_offset], {c_expr(member.val, lookup_sym)}); false; }})\n"
 
                 ret += ifdef_pop(1)
                 ret += "\t    ;\n"
@@ -815,10 +833,10 @@ LM_ALWAYS_INLINE static bool marshal_8(struct _marshal_ctx *ctx, uint64_t *val)
 LM_FLATTEN bool _{idprefix}stat_validate(struct _validate_ctx *ctx) {{
 \treturn validate_stat(ctx);
 }}
-LM_FLATTEN void _{idprefix}stat_unmarshal(struct _unmarshal_ctx *ctx, struct lib9p_stat *out) {{
+LM_FLATTEN void _{idprefix}stat_unmarshal(struct _unmarshal_ctx *ctx, struct {idprefix}stat *out) {{
 \tunmarshal_stat(ctx, out);
 }}
-LM_FLATTEN bool _{idprefix}stat_marshal(struct _marshal_ctx *ctx, struct lib9p_stat *val) {{
+LM_FLATTEN bool _{idprefix}stat_marshal(struct _marshal_ctx *ctx, struct {idprefix}stat *val) {{
 \treturn marshal_stat(ctx, val);
 }}
 """
diff --git a/lib9p/internal.h b/lib9p/internal.h
index d939d46..a648532 100644
--- a/lib9p/internal.h
+++ b/lib9p/internal.h
@@ -39,10 +39,12 @@ static_assert(CONFIG_9P_MAX_HOSTMSG_SIZE <= SSIZE_MAX);
 /* specialized contexts *******************************************************/
 
 struct _validate_ctx {
+	/* input */
 	struct lib9p_ctx        *ctx;
 	uint32_t                 net_size;
 	uint8_t                 *net_bytes;
 
+	/* output */
 	uint32_t                 net_offset;
 	/* Increment `host_extra` to pre-allocate space that is
 	 * "extra" beyond sizeof().  */
@@ -51,9 +53,11 @@ struct _validate_ctx {
 typedef bool (*_validate_fn_t)(struct _validate_ctx *ctx);
 
 struct _unmarshal_ctx {
+	/* input */
 	struct lib9p_ctx        *ctx;
 	uint8_t                 *net_bytes;
 
+	/* output */
 	uint32_t                 net_offset;
 	/* `extra` points to the beginning of unallocated space.  */
 	void                    *extra;
@@ -61,8 +65,10 @@ struct _unmarshal_ctx {
 typedef void (*_unmarshal_fn_t)(struct _unmarshal_ctx *ctx, void *out);
 
 struct _marshal_ctx {
+	/* input */
 	struct lib9p_ctx        *ctx;
 
+	/* output */
 	uint8_t                 *net_bytes;
 	uint32_t                 net_offset;
 };
diff --git a/lib9p/map.h b/lib9p/map.h
index b59c83d..ab9564f 100644
--- a/lib9p/map.h
+++ b/lib9p/map.h
@@ -1,6 +1,6 @@
-/* lib9p/map.h - A really dumb map/dict data structur
+/* lib9p/map.h - A really dumb map/dict data structure
  *
- * Copyright (C) 2024  Luke T. Shumaker <lukeshu@lukeshu.com>
+ * Copyright (C) 2024-2025  Luke T. Shumaker <lukeshu@lukeshu.com>
  * SPDX-License-Identifier: AGPL-3.0-or-later
  */
 
diff --git a/lib9p/srv.c b/lib9p/srv.c
index 0e58068..9837994 100644
--- a/lib9p/srv.c
+++ b/lib9p/srv.c
@@ -205,12 +205,12 @@ static void respond_error(struct _lib9p_srv_req *req) {
 
 /* read coroutine *************************************************************/
 
-static bool read_at_least(lo_interface net_stream_conn fd, uint8_t *buf, size_t goal, size_t *done) {
+static bool read_exactly(lo_interface net_stream_conn fd, uint8_t *buf, size_t goal, size_t *done) {
 	assert(buf);
 	assert(goal);
 	assert(done);
 	while (*done < goal) {
-		ssize_t r = LO_CALL(fd, read, &buf[*done], CONFIG_9P_MAX_MSG_SIZE - *done);
+		ssize_t r = LO_CALL(fd, read, &buf[*done], goal - *done);
 		if (r < 0) {
 			nonrespond_errorf("read: %s", net_strerror(-r));
 			return true;
@@ -263,14 +263,14 @@ static void handle_message(struct _lib9p_srv_req *ctx);
 		nextmsg:
 			/* Read the message.  */
 			size_t done = 0;
-			if (read_at_least(conn.fd, buf, 4, &done))
+			if (read_exactly(conn.fd, buf, 4, &done))
 				goto close;
 			size_t goal = uint32le_decode(buf);
 			if (goal < 7) {
 				nonrespond_errorf("T-message is impossibly small");
 				goto close;
 			}
-			if (read_at_least(conn.fd, buf, 7, &done))
+			if (read_exactly(conn.fd, buf, 7, &done))
 				goto close;
 			struct _lib9p_srv_req req = {
 				.parent_sess = &sess,
@@ -292,7 +292,7 @@ static void handle_message(struct _lib9p_srv_req *ctx);
 				respond_error(&req);
 				goto nextmsg;
 			}
-			if (read_at_least(conn.fd, buf, goal, &done))
+			if (read_exactly(conn.fd, buf, goal, &done))
 				goto close;
 
 			/* Handle the message...  */