Add a way to make private object members

9 files changed, 85 insertions, 11 deletions

diff --git a/lib9p/include/lib9p/srv.h b/lib9p/include/lib9p/srv.h
index 0617e57..ab7ec43 100644
--- a/lib9p/include/lib9p/srv.h
+++ b/lib9p/include/lib9p/srv.h
@@ -11,6 +11,7 @@
 #include <libcr_ipc/rpc.h>
 #include <libcr_ipc/chan.h>
 #include <libhw/generic/net.h>
+#include <libmisc/private.h>
 
 #include <lib9p/9p.h>
 
@@ -23,21 +24,14 @@ struct lib9p_srv_ctx {
 	uint32_t                 uid;
 	char                    *uname;
 
+	BEGIN_PRIVATE(LIB9P_SRV_H)
 	_lib9p_srv_flushch_t     _flushch;
+	END_PRIVATE(LIB9P_SRV_H)
 };
 
-static inline bool lib9p_srv_flush_requested(struct lib9p_srv_ctx *ctx) {
-	assert(ctx);
-	return _lib9p_srv_flushch_can_send(&ctx->_flushch);
-}
+bool lib9p_srv_flush_requested(struct lib9p_srv_ctx *ctx);
 
-static inline int lib9p_srv_acknowledge_flush(struct lib9p_srv_ctx *ctx) {
-	assert(ctx);
-	assert(_lib9p_srv_flushch_can_send(&ctx->_flushch));
-	lib9p_error(&ctx->basectx, LINUX_ECANCELED, "request canceled by flush");
-	_lib9p_srv_flushch_send(&ctx->_flushch, true);
-	return -1;
-}
+int lib9p_srv_acknowledge_flush(struct lib9p_srv_ctx *ctx);
 
 /* interface definitions ******************************************************/
 
@@ -47,6 +41,7 @@ struct __lib9p_srv_file;
 typedef struct __lib9p_srv_file {
 	struct lib9p_srv_file_vtable    *vtable;
 
+	BEGIN_PRIVATE(LIB9P_SRV_H)
 	/* Managed by srv.c, but should be cloned by ->vtable->clone().  */
 	struct __lib9p_srv_file         *_parent_dir; /* clone this
 
@@ -54,6 +49,7 @@ typedef struct __lib9p_srv_file {
 	/* ref type 1: an entry in fidmap
 	 * ref type 2: ->_parent_dir of another file */
 	unsigned int                     _refcount;
+	END_PRIVATE(LIB9P_SRV_H)
 } implements_lib9p_srv_file;
 
 struct lib9p_srv_file_vtable {
@@ -103,7 +99,9 @@ struct lib9p_srv {
 	implements_lib9p_srv_file *(*rootdir)(struct lib9p_srv_ctx *, char *treename);
 
 	/* For internal use */
+	BEGIN_PRIVATE(LIB9P_SRV_H)
 	_lib9p_srv_reqch_t    _reqch;
+	END_PRIVATE(LIB9P_SRV_H)
 };
 
 /**
diff --git a/lib9p/srv.c b/lib9p/srv.c
index 3a3807c..9192794 100644
--- a/lib9p/srv.c
+++ b/lib9p/srv.c
@@ -16,9 +16,25 @@
 #include <libcr_ipc/select.h>
 #include <libmisc/vcall.h>
 
+#define IMPLEMENTATION_FOR_LIB9P_SRV_H YES
 #include <lib9p/srv.h>
 #include "internal.h"
 
+/* context ********************************************************************/
+
+bool lib9p_srv_flush_requested(struct lib9p_srv_ctx *ctx) {
+	assert(ctx);
+	return _lib9p_srv_flushch_can_send(&ctx->_flushch);
+}
+
+int lib9p_srv_acknowledge_flush(struct lib9p_srv_ctx *ctx) {
+	assert(ctx);
+	assert(_lib9p_srv_flushch_can_send(&ctx->_flushch));
+	lib9p_error(&ctx->basectx, LINUX_ECANCELED, "request canceled by flush");
+	_lib9p_srv_flushch_send(&ctx->_flushch, true);
+	return -1;
+}
+
 /* structs ********************************************************************/
 
 #define FIDFLAG_OPEN_R (1<<0)
diff --git a/libhw/host_include/libhw/host_net.h b/libhw/host_include/libhw/host_net.h
index 1b1ba7a..bfef5c9 100644
--- a/libhw/host_include/libhw/host_net.h
+++ b/libhw/host_include/libhw/host_net.h
@@ -9,20 +9,26 @@
 
 #include <stdint.h> /* for uint16_6 */
 
+#include <libmisc/private.h>
+
 #include <libhw/generic/net.h>
 
 struct _hostnet_tcp_conn {
 	implements_net_stream_conn;
 
+	BEGIN_PRIVATE(LIBHW_HOST_NET_H)
 	int                              fd;
 	uint64_t                         read_deadline_ns;
+	END_PRIVATE(LIBHW_HOST_NET_H)
 };
 
 struct hostnet_tcp_listener {
 	implements_net_stream_listener;
 
+	BEGIN_PRIVATE(LIBHW_HOST_NET_H)
 	int                              fd;
 	struct _hostnet_tcp_conn         active_conn;
+	END_PRIVATE(LIBHW_HOST_NET_H)
 };
 
 void hostnet_tcp_listener_init(struct hostnet_tcp_listener *self, uint16_t port);
@@ -30,8 +36,10 @@ void hostnet_tcp_listener_init(struct hostnet_tcp_listener *self, uint16_t port)
 struct hostnet_udp_conn {
 	implements_net_packet_conn;
 
+	BEGIN_PRIVATE(LIBHW_HOST_NET_H)
 	int                              fd;
 	uint64_t                         read_deadline_ns;
+	END_PRIVATE(LIBHW_HOST_NET_H)
 };
 
 void hostnet_udp_conn_init(struct hostnet_udp_conn *self, uint16_t port);
diff --git a/libhw/host_net.c b/libhw/host_net.c
index 1563ced..904019a 100644
--- a/libhw/host_net.c
+++ b/libhw/host_net.c
@@ -23,6 +23,8 @@
 #include <libmisc/vcall.h>
 
 #include <libhw/generic/bootclock.h>
+
+#define IMPLEMENTATION_FOR_LIBHW_HOST_NET_H YES
 #include <libhw/host_net.h>
 
 /* common *********************************************************************/
diff --git a/libhw/rp2040_hwspi.c b/libhw/rp2040_hwspi.c
index 96c3d14..b4adeb7 100644
--- a/libhw/rp2040_hwspi.c
+++ b/libhw/rp2040_hwspi.c
@@ -12,6 +12,7 @@
 
 #include <libmisc/vcall.h>
 
+#define IMPLEMENTATION_FOR_LIBHW_RP2040_HWSPI_H YES
 #include <libhw/rp2040_hwspi.h>
 
 static void rp2040_hwspi_readwritev(implements_spi *, const struct bidi_iovec *iov, int iovcnt);
diff --git a/libhw/rp2040_include/libhw/rp2040_hwspi.h b/libhw/rp2040_include/libhw/rp2040_hwspi.h
index db8285d..8d90dbb 100644
--- a/libhw/rp2040_include/libhw/rp2040_hwspi.h
+++ b/libhw/rp2040_include/libhw/rp2040_hwspi.h
@@ -10,6 +10,8 @@
 
 #include <pico/binary_info.h> /* for bi_* */
 
+#include <libmisc/private.h>
+
 #include <libhw/generic/spi.h>
 
 enum rp2040_hwspi_instance {
@@ -20,8 +22,10 @@ enum rp2040_hwspi_instance {
 struct rp2040_hwspi {
 	implements_spi;
 
+	BEGIN_PRIVATE(LIBHW_RP2040_HWSPI_H)
 	void /*spi_inst_t*/    *inst;
 	uint                    pin_cs;
+	END_PRIVATE(LIBHW_RP2040_HWSPI_H)
 };
 
 /**
diff --git a/libhw/rp2040_include/libhw/w5500.h b/libhw/rp2040_include/libhw/w5500.h
index 6f12c39..037d4f1 100644
--- a/libhw/rp2040_include/libhw/w5500.h
+++ b/libhw/rp2040_include/libhw/w5500.h
@@ -9,6 +9,7 @@
 
 #include <libcr_ipc/sema.h>
 #include <libcr_ipc/mutex.h>
+#include <libmisc/private.h>
 
 #include <libhw/generic/net.h>
 #include <libhw/generic/spi.h>
@@ -17,13 +18,16 @@ struct _w5500_tcp_conn {
 	/* const-after-init */
 	implements_net_stream_conn;
 	/* mutable */
+	BEGIN_PRIVATE(LIBHW_W5500_H)
 	bool                             read_open;
 	bool                             write_open;
+	END_PRIVATE(LIBHW_W5500_H)
 };
 
 struct _w5500_tcp_listener {
 	/* const-after-init */
 	implements_net_stream_listener;
+	BEGIN_PRIVATE(LIBHW_W5500_H)
 	uint8_t                          socknum;
 	struct _w5500_tcp_conn           active_conn;
 
@@ -31,11 +35,13 @@ struct _w5500_tcp_listener {
 	uint16_t                         port;
 	cr_mutex_t                       cmd_mu;
 	cr_sema_t                        listen_sema, read_sema;
+	END_PRIVATE(LIBHW_W5500_H)
 };
 
 struct w5500 {
 	/* const-after-init */
 	implements_spi                  *spidev;
+	BEGIN_PRIVATE(LIBHW_W5500_H)
 	uint                             pin_intr;
 	uint                             pin_reset;
 	struct net_eth_addr              hwaddr;
@@ -44,6 +50,7 @@ struct w5500 {
 	uint16_t                         next_local_port;
 	struct _w5500_tcp_listener       listeners[8];
 	cr_sema_t                        intr;
+	END_PRIVATE(LIBHW_W5500_H)
 };
 
 /**
diff --git a/libhw/w5500.c b/libhw/w5500.c
index a141fb3..0d9cd01 100644
--- a/libhw/w5500.c
+++ b/libhw/w5500.c
@@ -73,6 +73,7 @@
 #include <libcr/coroutine.h> /* for cr_yield() */
 #include <libmisc/vcall.h>   /* for VCALL_SELF() */
 
+#define IMPLEMENTATION_FOR_LIBHW_W5500_H YES
 #include <libhw/w5500.h>
 
 #include "w5500_ll.h"
diff --git a/libmisc/include/libmisc/private.h b/libmisc/include/libmisc/private.h
new file mode 100644
index 0000000..0eb8c42
--- /dev/null
+++ b/libmisc/include/libmisc/private.h
@@ -0,0 +1,37 @@
+/* libmisc/private.h - Utilities to hide struct fields
+ *
+ * Copyright (C) 2024  Luke T. Shumaker <lukeshu@lukeshu.com>
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+#ifndef _LIBMISC_CPPUTIL_H_
+#define _LIBMISC_CPPUTIL_H_
+
+/* primitive utilities */
+
+#define _SECOND(a, b, ...) b
+
+#define _CAT(a, b) a ## b
+#define _CAT2(a, b) _CAT(a, b)
+#define _EAT(...)
+#define _EXPAND(...) __VA_ARGS__
+
+/* conditionals */
+
+#define _T xxTxx
+#define _F xxFxx
+
+#define _SENTINEL() bogus, _T /* a magic sentinel value */
+#define _IS_SENTINEL(...) _SECOND(__VA_ARGS__, _F)
+
+#define _IF(cond) _CAT(_IF__, cond) /* _IF(cond)(then)(else) */
+#define _IF__xxTxx(...) __VA_ARGS__ _EAT
+#define _IF__xxFxx(...) _EXPAND
+
+/* high-level functionality */
+
+#define YES _SENTINEL()
+#define BEGIN_PRIVATE(name) _IF(_IS_SENTINEL(IMPLEMENTATION_FOR_##name))()(struct {)
+#define END_PRIVATE(name)   _IF(_IS_SENTINEL(IMPLEMENTATION_FOR_##name))()(} _CAT2(_HIDDEN_, __COUNTER__);)
+
+#endif /* _LIBMISC_CPPUTIL_H_ */