libmisc

13 files changed, 163 insertions, 157 deletions

diff --git a/cmd/sbc_harness/CMakeLists.txt b/cmd/sbc_harness/CMakeLists.txt
index 04f231d..c42fecb 100644
--- a/cmd/sbc_harness/CMakeLists.txt
+++ b/cmd/sbc_harness/CMakeLists.txt
@@ -18,8 +18,8 @@ target_link_libraries(sbc_harness
 	hardware_spi
 	hardware_gpio
 
+	libmisc
 	libusb
-	libnet
 )
 
 pico_enable_stdio_usb(sbc_harness 0)
diff --git a/cmd/sbc_harness/hw/rp2040_hwspi.c b/cmd/sbc_harness/hw/rp2040_hwspi.c
index e6e4566..dd9a577 100644
--- a/cmd/sbc_harness/hw/rp2040_hwspi.c
+++ b/cmd/sbc_harness/hw/rp2040_hwspi.c
@@ -10,9 +10,11 @@
 #include <hardware/spi.h>  /* pico-sdk:hardware_spi */
 #include <hardware/gpio.h> /* pico-sdk:hardware_gpio5 */
 
+#include <libmisc/vcall.h>
+
 #include "hw/rp2040_hwspi.h"
 
-static void rp2040_hwspi_readwritev(struct spi *_self, const struct bidi_iovec *iov, int iovcnt);
+static void rp2040_hwspi_readwritev(implements_spi *, const struct bidi_iovec *iov, int iovcnt);
 
 struct spi_vtable rp2040_hwspi_vtable = {
 	.readwritev = rp2040_hwspi_readwritev,
@@ -96,8 +98,8 @@ void _rp2040_hwspi_init(struct rp2040_hwspi *self,
 	self->pin_cs = pin_cs;
 }
 
-static void rp2040_hwspi_readwritev(struct spi *_self, const struct bidi_iovec *iov, int iovcnt) {
-	struct rp2040_hwspi *self = (struct rp2040_hwspi *)_self;
+static void rp2040_hwspi_readwritev(implements_spi *_self, const struct bidi_iovec *iov, int iovcnt) {
+	struct rp2040_hwspi *self = VCALL_SELF(struct rp2040_hwspi, implements_spi, _self);
 	assert(self);
 	spi_inst_t *inst = self->inst;
 
diff --git a/cmd/sbc_harness/hw/rp2040_hwspi.h b/cmd/sbc_harness/hw/rp2040_hwspi.h
index 8793fd6..8bf783f 100644
--- a/cmd/sbc_harness/hw/rp2040_hwspi.h
+++ b/cmd/sbc_harness/hw/rp2040_hwspi.h
@@ -18,7 +18,7 @@ enum rp2040_hwspi_instance {
 };
 
 struct rp2040_hwspi {
- 	struct spi_vtable      *vtable;
+	implements_spi;
 
 	void /*spi_inst_t*/    *inst;
 	uint                    pin_cs;
diff --git a/cmd/sbc_harness/hw/spi.h b/cmd/sbc_harness/hw/spi.h
index 86b831e..653e80f 100644
--- a/cmd/sbc_harness/hw/spi.h
+++ b/cmd/sbc_harness/hw/spi.h
@@ -40,11 +40,8 @@ struct spi_vtable {
 	void (*readwritev)(struct spi *, const struct bidi_iovec *iov, int iovcnt);
 };
 
-struct spi {
+typedef struct spi {
  	struct spi_vtable      *vtable;
-
-	/* This is where your implementation data goes.  */
-	char                    data[0];
-};
+} implements_spi;
 
 #endif /* _HW_SPI_H_ */
diff --git a/cmd/sbc_harness/hw/w5500.c b/cmd/sbc_harness/hw/w5500.c
index e32c589..8e3dab0 100644
--- a/cmd/sbc_harness/hw/w5500.c
+++ b/cmd/sbc_harness/hw/w5500.c
@@ -1,4 +1,4 @@
-/* hw/w5500.c - libnet implementation for the WIZnet W5500 chip
+/* hw/w5500.c - libmisc/net.h implementation for the WIZnet W5500 chip
  *
  * Copyright (C) 2024  Luke T. Shumaker <lukeshu@lukeshu.com>
  * SPDX-Licence-Identifier: AGPL-3.0-or-later
@@ -42,6 +42,8 @@
 #include <hardware/gpio.h> /* pico-sdk:hardware_gpio5 */
 
 #include <libcr/coroutine.h>
+#include <libmisc/vcall.h>
+
 #include "hw/w5500.h"
 #include "config.h"
 
@@ -110,7 +112,7 @@ void w5500_spiframe_write(struct spi *spidev, uint16_t addr, uint8_t block, void
 		{.iov_read_dst = NULL, .iov_write_src = header, .iov_len = sizeof(header)},
 		{.iov_read_dst = NULL, .iov_write_src = data,   .iov_len = data_len},
 	};
-	spidev->vtable->readwritev(spidev, iov, 2);
+	VCALL(spidev, readwritev, iov, 2);
 }
 
 void w5500_spiframe_read(struct spi *spidev, uint16_t addr, uint8_t block, void *data, size_t data_len) {
@@ -128,7 +130,7 @@ void w5500_spiframe_read(struct spi *spidev, uint16_t addr, uint8_t block, void
 		{.iov_read_dst = NULL, .iov_write_src = header, .iov_len = sizeof(header)},
 		{.iov_read_dst = data, .iov_write_src = NULL,   .iov_len = data_len},
 	};
-	spidev->vtable->readwritev(spidev, iov, 2);
+	VCALL(spidev, readwritev, iov, 2);
 }
 
 /* Offsets and sizes for use with that protocol.  *****************************/
@@ -357,16 +359,16 @@ static_assert(sizeof(struct w5500_block_sock_reg) == 0x30);
 
 /* init() *********************************************************************/
 
-static struct libnet_conn *w5500_accept(struct libnet_listener *_listener);
-static ssize_t w5500_read(struct libnet_conn *conn, void *buf, size_t count);
-static ssize_t w5500_write(struct libnet_conn *conn, void *buf, size_t count);
-static int w5500_close(struct libnet_conn *conn, bool rd, bool wr);
+static implements_net_conn *w5500_accept(implements_net_listener *_listener);
+static ssize_t w5500_read(implements_net_conn *conn, void *buf, size_t count);
+static ssize_t w5500_write(implements_net_conn *conn, void *buf, size_t count);
+static int w5500_close(implements_net_conn *conn, bool rd, bool wr);
 
-static struct libnet_listener_vtable w5500_listener_vtable = {
+static struct net_listener_vtable w5500_listener_vtable = {
 	.accept = w5500_accept,
 };
 
-static struct libnet_conn_vtable w5500_conn_vtable = {
+static struct net_conn_vtable w5500_conn_vtable = {
 	.read  = w5500_read,
 	.write = w5500_write,
 	.close = w5500_close,
@@ -381,7 +383,7 @@ uint16_t w5500_get_local_port(struct w5500 *self) {
 
 void _w5500_init(struct w5500 *chip,
                  struct spi* spi, uint pin_intr, uint pin_reset,
-                 struct eth_addr addr) {
+                 struct net_eth_addr addr) {
 	chip->spidev = spi;
 	chip->pin_reset = pin_reset;
 	for (uint8_t i = 0; i < 8; i++) {
@@ -418,12 +420,12 @@ void w5500_netcfg(struct w5500 *chip, struct w5500_netcfg cfg) {
 
 /* listen() *******************************************************************/
 
-struct libnet_listener *w5500_listen(struct w5500 *chip, uint8_t socknum, uint16_t port) {
+implements_net_listener *w5500_listen(struct w5500 *chip, uint8_t socknum, uint16_t port) {
 	assert(chip);
 	assert(socknum < 8);
 	assert(port);
 
-	w5500_close((struct libnet_conn *)&chip->_listeners[socknum].active_conn, true, true);
+	w5500_close(&chip->_listeners[socknum].active_conn, true, true);
 	REGWRITE_SOCK(chip->spidev, socknum, mode, MODE_TCP);
 	REGWRITE_SOCK(chip->spidev, socknum, local_port, ((uint8_t[2]){port>>8, port}));
 	REGWRITE_SOCK(chip->spidev, socknum, command, CMD_OPEN);
@@ -432,13 +434,13 @@ struct libnet_listener *w5500_listen(struct w5500 *chip, uint8_t socknum, uint16
 	while (REGREAD_SOCK(chip->spidev, socknum, state, uint8_t) != STATE_TCP_INIT)
 		cr_yield();
 
-	return (struct libnet_listener *)&chip->_listeners[socknum];
+	return &chip->_listeners[socknum];
 }
 
 /* accept() *******************************************************************/
 
 #define ASSERT_LISTENER()                                               \
-	struct _w5500_listener *self = (struct _w5500_listener *)_self; \
+	struct _w5500_listener *self = VCALL_SELF(struct _w5500_listener, implements_net_listener, _self); \
 	assert(self);                                                   \
 	                                                                \
 	struct w5500 *chip = self->chip;                                \
@@ -446,7 +448,7 @@ struct libnet_listener *w5500_listen(struct w5500 *chip, uint8_t socknum, uint16
 	assert(chip);                                                   \
 	assert(socknum < 8)
 
-static struct libnet_conn *w5500_accept(struct libnet_listener *_self) {
+static implements_net_conn *w5500_accept(implements_net_listener *_self) {
 	ASSERT_LISTENER();
 
 	REGWRITE_SOCK(chip->spidev, socknum, command, CMD_LISTEN);
@@ -460,7 +462,7 @@ static struct libnet_conn *w5500_accept(struct libnet_listener *_self) {
 			cr_yield();
 			break;
 		default:
-			return (struct libnet_conn *)&self->active_conn;
+			return &self->active_conn;
 		}
 	}
 }
@@ -468,7 +470,7 @@ static struct libnet_conn *w5500_accept(struct libnet_listener *_self) {
 /* write() ********************************************************************/
 
 #define ASSERT_CONN() \
-	struct _w5500_conn *self = (struct _w5500_conn *)_self; \
+	struct _w5500_conn *self = VCALL_SELF(struct _w5500_conn, implements_net_conn, _self); \
 	assert(self);                                           \
 	                                                        \
 	struct w5500 *chip = self->parent_listener->chip;       \
@@ -476,7 +478,7 @@ static struct libnet_conn *w5500_accept(struct libnet_listener *_self) {
 	assert(chip);                                           \
 	assert(socknum < 8)
 
-static ssize_t w5500_write(struct libnet_conn *_self, void *buf, size_t count) {
+static ssize_t w5500_write(implements_net_conn *_self, void *buf, size_t count) {
 	ASSERT_CONN();
 	assert(buf);
 	assert(count);
@@ -484,7 +486,7 @@ static ssize_t w5500_write(struct libnet_conn *_self, void *buf, size_t count) {
 	// TODO
 }
 
-static int w5500_close(struct libnet_conn *_self, bool rd, bool wr) {
+static int w5500_close(implements_net_conn *_self, bool rd, bool wr) {
 	ASSERT_CONN();
 
 	REGWRITE_SOCK(chip->spidev, socknum, command, CMD_CLOSE);
diff --git a/cmd/sbc_harness/hw/w5500.h b/cmd/sbc_harness/hw/w5500.h
index bb629c5..4ec6edd 100644
--- a/cmd/sbc_harness/hw/w5500.h
+++ b/cmd/sbc_harness/hw/w5500.h
@@ -1,4 +1,4 @@
-/* hw/w5500.h - libnet implementation for the WIZnet W5500 chip
+/* hw/w5500.h - libmisc/net.h implementation for the WIZnet W5500 chip
  *
  * Copyright (C) 2024  Luke T. Shumaker <lukeshu@lukeshu.com>
  * SPDX-Licence-Identifier: AGPL-3.0-or-later
@@ -7,20 +7,20 @@
 #ifndef _HW_W5500_H_
 #define _HW_W5500_H_
 
-#include <libnet/libnet.h>
+#include <libmisc/net.h>
 
 #include "hw/spi.h"
 
 struct _w5500_listener;
 
 struct _w5500_conn {
-	struct libnet_conn_vtable       *vtable;
+	implements_net_conn;
 
 	struct _w5500_listener          *parent_listener;
 };
 
 struct _w5500_listener {
-	struct libnet_listener_vtable   *vtable;
+	implements_net_listener;
 
 	struct w5500                    *chip;
 	uint8_t                          socknum;
@@ -56,7 +56,7 @@ struct w5500 {
 	} while (0)
 void _w5500_init(struct w5500 *self,
                  struct spi* spi, uint pin_intr, uint pin_reset,
-                 struct eth_addr addr);
+                 struct net_eth_addr addr);
 
 /**
  * TODO.
@@ -64,9 +64,9 @@ void _w5500_init(struct w5500 *self,
 void w5500_reset(struct w5500 *self);
 
 struct w5500_netcfg {
-	struct ip4_addr gateway_addr;
-	struct ip4_addr subnet_mask;
-	struct ip4_addr addr;
+	struct net_ip4_addr gateway_addr;
+	struct net_ip4_addr subnet_mask;
+	struct net_ip4_addr addr;
 };
 
 /**
@@ -74,6 +74,6 @@ struct w5500_netcfg {
  */
 void w5500_netcfg(struct w5500 *self, struct w5500_netcfg cfg);
 
-struct libnet_listener *w5500_listen(struct w5500 *self, uint8_t socknum, uint16_t port);
+implements_net_listener *w5500_listen(struct w5500 *self, uint8_t socknum, uint16_t port);
 
 #endif /* _HW_W5500_H_ */
diff --git a/cmd/sbc_harness/main.c b/cmd/sbc_harness/main.c
index 9564665..c6df8f5 100644
--- a/cmd/sbc_harness/main.c
+++ b/cmd/sbc_harness/main.c
@@ -44,10 +44,10 @@ int main() {
 	                  19,  /* PIN_MOSI */
 	                  18,  /* PIN_CLK */
 	                  17); /* PIN_CS */
-	w5500_init(&dev_w5500, "W5500", (struct spi *)&dev_spi,
+	w5500_init(&dev_w5500, "W5500", &dev_spi,
 	           21, /* PIN_INTR */
 	           20, /* PIN_RESET */
-	           ((struct eth_addr){{0xDE,0xAD,0xBE,0xEF,0x01,0x02}}));
+	           ((struct net_eth_addr){{0xDE,0xAD,0xBE,0xEF,0x01,0x02}}));
 
 	usb_common_earlyinit();
 	usb_keyboard_init();
diff --git a/cmd/srv9p/CMakeLists.txt b/cmd/srv9p/CMakeLists.txt
index 61bd5c2..52e5171 100644
--- a/cmd/srv9p/CMakeLists.txt
+++ b/cmd/srv9p/CMakeLists.txt
@@ -18,7 +18,7 @@ target_include_directories(srv9p PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/config)
 target_link_libraries(srv9p
 	libcr
 	libcr_ipc
-	libnet
+	libmisc
 	lib9p
 )
 
diff --git a/cmd/srv9p/gnet.c b/cmd/srv9p/gnet.c
index 92e74c7..d7e8717 100644
--- a/cmd/srv9p/gnet.c
+++ b/cmd/srv9p/gnet.c
@@ -1,4 +1,4 @@
-/* srv9p/gnet.c - libnet implementation for libcr + GNU libc
+/* srv9p/gnet.c - libmisc/net.h implementation for libcr + GNU libc
  *
  * Copyright (C) 2024  Luke T. Shumaker <lukeshu@lukeshu.com>
  * SPDX-Licence-Identifier: AGPL-3.0-or-later
@@ -20,6 +20,7 @@
 #include <signal.h>     /* for siginfo_t, struct sigaction, enum sigval, sigaction(), SIGRTMIN, SIGRTMAX, SA_SIGINFO */
 
 #include <libcr/coroutine.h>
+#include <libmisc/vcall.h>
 
 #include "gnet.h"
 
@@ -71,16 +72,16 @@ static inline bool RUN_PTHREAD(void *(*fn)(void *), void *args) {
 
 /* init() ( AKA socket(3) + listen(3) )****************************************/
 
-static struct libnet_conn *gnet_accept(struct libnet_listener *_listener);
-static ssize_t gnet_read(struct libnet_conn *conn, void *buf, size_t count);
-static ssize_t gnet_write(struct libnet_conn *conn, void *buf, size_t count);
-static int gnet_close(struct libnet_conn *conn, bool rd, bool wr);
+static implements_net_conn *gnet_accept(implements_net_listener *_listener);
+static ssize_t gnet_read(implements_net_conn *conn, void *buf, size_t count);
+static ssize_t gnet_write(implements_net_conn *conn, void *buf, size_t count);
+static int gnet_close(implements_net_conn *conn, bool rd, bool wr);
 
-static struct libnet_listener_vtable gnet_listener_vtable = {
+static struct net_listener_vtable gnet_listener_vtable = {
 	.accept = gnet_accept,
 };
 
-static struct libnet_conn_vtable gnet_conn_vtable = {
+static struct net_conn_vtable gnet_conn_vtable = {
 	.read  = gnet_read,
 	.write = gnet_write,
 	.close = gnet_close,
@@ -131,8 +132,8 @@ static void *_pthread_accept(void *_args) {
 	return NULL;
 };
 
-static struct libnet_conn *gnet_accept(struct libnet_listener *_listener) {
-	struct gnet_listener *listener = (struct gnet_listener *)_listener;
+static implements_net_conn *gnet_accept(implements_net_listener *_listener) {
+	struct gnet_listener *listener = VCALL_SELF(struct gnet_listener, implements_net_listener, _listener);
 	assert(listener);
 
 	int ret_connfd;
@@ -147,7 +148,7 @@ static struct libnet_conn *gnet_accept(struct libnet_listener *_listener) {
 
 	listener->active_conn.vtable = &gnet_conn_vtable;
 	listener->active_conn.fd = ret_connfd;
-	return (struct libnet_conn *)&listener->active_conn;
+	return &listener->active_conn;
 }
 
 /* read() *********************************************************************/
@@ -172,8 +173,8 @@ static void *_pthread_read(void *_args) {
 	return NULL;
 };
 
-static ssize_t gnet_read(struct libnet_conn *_conn, void *buf, size_t count) {
-	struct _gnet_conn *conn = (struct _gnet_conn *)_conn;
+static ssize_t gnet_read(implements_net_conn *_conn, void *buf, size_t count) {
+	struct _gnet_conn *conn = VCALL_SELF(struct _gnet_conn, implements_net_conn, _conn);
 	assert(conn);
 
 	ssize_t ret;
@@ -222,8 +223,8 @@ static void *_pthread_write(void *_args) {
 	return NULL;
 };
 
-static ssize_t gnet_write(struct libnet_conn *_conn, void *buf, size_t count) {
-	struct _gnet_conn *conn = (struct _gnet_conn *)_conn;
+static ssize_t gnet_write(implements_net_conn *_conn, void *buf, size_t count) {
+	struct _gnet_conn *conn = VCALL_SELF(struct _gnet_conn, implements_net_conn, _conn);
 	assert(conn);
 
 	ssize_t ret;
@@ -244,8 +245,8 @@ static ssize_t gnet_write(struct libnet_conn *_conn, void *buf, size_t count) {
 
 /* close() ********************************************************************/
 
-static int gnet_close(struct libnet_conn *_conn, bool rd, bool wr) {
-	struct _gnet_conn *conn = (struct _gnet_conn *)_conn;
+static int gnet_close(implements_net_conn *_conn, bool rd, bool wr) {
+	struct _gnet_conn *conn = VCALL_SELF(struct _gnet_conn, implements_net_conn, _conn);
 	assert(conn);
 
 	int how;
diff --git a/cmd/srv9p/gnet.h b/cmd/srv9p/gnet.h
index d43874f..01f2d40 100644
--- a/cmd/srv9p/gnet.h
+++ b/cmd/srv9p/gnet.h
@@ -1,4 +1,4 @@
-/* srv9p/gnet.h - libnet implementation for libcr + GNU libc
+/* srv9p/gnet.h - libmisc/net.h implementation for libcr + GNU libc
  *
  * Copyright (C) 2024  Luke T. Shumaker <lukeshu@lukeshu.com>
  * SPDX-Licence-Identifier: AGPL-3.0-or-later
@@ -9,16 +9,16 @@
 
 #include <stdint.h> /* for uint16_6 */
 
-#include <libnet/libnet.h>
+#include <libmisc/net.h>
 
 struct _gnet_conn {
-	struct libnet_conn_vtable       *vtable;
+	implements_net_conn;
 
 	int                              fd;
 };
 
 struct gnet_listener {
-	struct libnet_listener_vtable   *vtable;
+	implements_net_listener;
 
 	int                              fd;
 	struct _gnet_conn                active_conn;
diff --git a/cmd/srv9p/main.c b/cmd/srv9p/main.c
index ae0e34e..d83fac4 100644
--- a/cmd/srv9p/main.c
+++ b/cmd/srv9p/main.c
@@ -8,7 +8,7 @@
 #include <stdio.h>
 
 #include <libcr/coroutine.h>
-#include <libnet/libnet.h>
+#include <libmisc/net.h>
 #include <lib9p/srv.h>
 
 #include "static9p.h"
@@ -29,8 +29,8 @@
 
 /* file tree ******************************************************************/
 
-#define FILE_METADATA(NAME) {                                             \
-		.header = { .vtable = &static_file_vtable },              \
+#define FILE_COMMON(NAME) {                                             \
+		.vtable = &static_file_vtable,                            \
                                                                           \
 		.u_name = "root", .u_num = 0, /* owner user */            \
 		.g_name = "root", .g_num = 0, /* owner group */           \
@@ -43,8 +43,8 @@
 		.mtime   = 1728337904,                                    \
 	}
 
-#define DIR_METADATA(NAME) {                                              \
-		.header = { .vtable = &static_dir_vtable },               \
+#define DIR_COMMON(NAME) {                                              \
+		.vtable = &static_dir_vtable,                             \
                                                                           \
 		.u_name = "root", .u_num = 0, /* owner user */            \
 		.g_name = "root", .g_num = 0, /* owner group */           \
@@ -59,28 +59,28 @@
 
 #define STATIC_FILE(STRNAME, SYMNAME)                           \
 	&((static struct static_file){                          \
-		.metadata   = FILE_METADATA(STRNAME),           \
-		.data_start = _binary_static_##SYMNAME##_start, \
-		.data_end   = _binary_static_##SYMNAME##_end,   \
-	}).metadata.header
+		._static_common = FILE_COMMON(STRNAME),           \
+		.data_start     = _binary_static_##SYMNAME##_start, \
+		.data_end       = _binary_static_##SYMNAME##_end,   \
+	})
 
 static struct static_dir root = {
-	.metadata = DIR_METADATA(""),
+	._static_common = DIR_COMMON(""),
 	.members = {
 		&((static struct static_dir){
-			.metadata = DIR_METADATA("Documentation"),
+			._static_common = DIR_COMMON("Documentation"),
 			.members = {
 				STATIC_FILE("x", Documentation_x),
 				NULL
 			},
-		}).metadata.header,
+		}),
 		STATIC_FILE("README.md", README_md),
 		NULL,
 	},
 };
 
-static struct lib9p_srv_file *get_root(struct lib9p_srv_ctx *UNUSED(ctx), char *UNUSED(treename)) {
-	return &root.metadata.header;
+static implements_lib9p_srv_file *get_root(struct lib9p_srv_ctx *UNUSED(ctx), char *UNUSED(treename)) {
+	return &root;
 }
 
 /* main ***********************************************************************/
@@ -94,7 +94,7 @@ static COROUTINE read_cr(void *_srv) {
 	struct gnet_listener listener;
 	gnet_listener_init(&listener, 9000);
 
-	lib9p_srv_read_cr(srv, (struct libnet_listener *)&listener);
+	lib9p_srv_read_cr(srv, &listener);
 
 	cr_end();
 }
diff --git a/cmd/srv9p/static9p.c b/cmd/srv9p/static9p.c
index f508ff1..47c07be 100644
--- a/cmd/srv9p/static9p.c
+++ b/cmd/srv9p/static9p.c
@@ -6,61 +6,63 @@
 
 #include <assert.h>
 
+#include <libmisc/vcall.h>
+
 #include "static9p.h"
 
 #define UNUSED(name) /* name __attribute__((unused)) */
 #define p9_str(cstr)    ((struct lib9p_s){ .len = strlen(cstr), .utf8 = cstr })
 #define p9_nulstr       ((struct lib9p_s){ .len = 0, .utf8 = NULL })
 
-/* common metadata ************************************************************/
+/* common *********************************************************************/
 
-static struct lib9p_srv_file *static_metadata_clone(struct lib9p_srv_ctx *ctx, struct lib9p_srv_file *_file) {
+static implements_lib9p_srv_file *static_common_clone(implements_lib9p_srv_file *_self, struct lib9p_srv_ctx *ctx) {
+	_static_common *self = VCALL_SELF(_static_common, implements_lib9p_srv_file, _self);
+	assert(self);
 	assert(ctx);
-	struct static_metadata *file = (struct static_metadata *)_file;
-	assert(file);
 
-	return &file->header;
+	return self;
 }
 
-static void static_metadata_free(struct lib9p_srv_ctx *ctx, struct lib9p_srv_file *_file) {
+static void static_common_free(implements_lib9p_srv_file *_self, struct lib9p_srv_ctx *ctx) {
+	_static_common *self = VCALL_SELF(_static_common, implements_lib9p_srv_file, _self);
+	assert(self);
 	assert(ctx);
-	struct static_metadata *file = (struct static_metadata *)_file;
-	assert(file);
 
 	/* do nothing */
 }
 
-static uint32_t static_metadata_io(struct lib9p_srv_ctx *ctx, struct lib9p_srv_file *_file, lib9p_o_t UNUSED(flags)) {
+static uint32_t static_common_io(implements_lib9p_srv_file *_self, struct lib9p_srv_ctx *ctx, lib9p_o_t UNUSED(flags)) {
+	_static_common *self = VCALL_SELF(_static_common, implements_lib9p_srv_file, _self);
+	assert(self);
 	assert(ctx);
-	struct static_metadata *file = (struct static_metadata *)_file;
-	assert(file);
 
 	return 0;
 }
 
-static void static_metadata_wstat(struct lib9p_srv_ctx *ctx, struct lib9p_srv_file *_file,
+static void static_common_wstat(implements_lib9p_srv_file *_self, struct lib9p_srv_ctx *ctx,
                               struct lib9p_stat UNUSED(new)) {
+	_static_common *self = VCALL_SELF(_static_common, implements_lib9p_srv_file, _self);
+	assert(self);
 	assert(ctx);
-	struct static_metadata *file = (struct static_metadata *)_file;
-	assert(file);
 
 	lib9p_error(&ctx->basectx, LINUX_EROFS, "read-only part of filesystem");
 }
 
-static void static_metadata_remove(struct lib9p_srv_ctx *ctx, struct lib9p_srv_file *_file) {
+static void static_common_remove(implements_lib9p_srv_file *_self, struct lib9p_srv_ctx *ctx) {
+	_static_common *self = VCALL_SELF(_static_common, implements_lib9p_srv_file, _self);
+	assert(self);
 	assert(ctx);
-	struct static_metadata *file = (struct static_metadata *)_file;
-	assert(file);
 
 	lib9p_error(&ctx->basectx, LINUX_EROFS, "read-only part of filesystem");
 }
 
 /* dir ************************************************************************/
 
-static struct lib9p_stat static_dir_stat(struct lib9p_srv_ctx *ctx, struct lib9p_srv_file *_file) {
+static struct lib9p_stat static_dir_stat(implements_lib9p_srv_file *_self, struct lib9p_srv_ctx *ctx) {
+	struct static_dir *self = VCALL_SELF(struct static_dir, implements_lib9p_srv_file, _self);
+	assert(self);
 	assert(ctx);
-	struct static_dir *file = (struct static_dir *)_file;
-	assert(file);
 
 	return (struct lib9p_stat){
 		.kern_type                      = 0,
@@ -68,32 +70,32 @@ static struct lib9p_stat static_dir_stat(struct lib9p_srv_ctx *ctx, struct lib9p
 		.file_qid                       = {
 			.type = LIB9P_QT_DIR,
 			.vers = 1,
-			.path = file->metadata.pathnum,
+			.path = self->pathnum,
 		},
-		.file_mode                = LIB9P_DM_DIR | (file->metadata.perm & 0555),
-		.file_atime               = file->metadata.atime,
-		.file_mtime               = file->metadata.mtime,
+		.file_mode                = LIB9P_DM_DIR | (self->perm & 0555),
+		.file_atime               = self->atime,
+		.file_mtime               = self->mtime,
 		.file_size                = 0,
-		.file_name                = p9_str(file->metadata.name),
-		.file_owner_uid           = p9_str(file->metadata.u_name),
-		.file_owner_gid           = p9_str(file->metadata.g_name),
-		.file_last_modified_uid   = p9_str(file->metadata.m_name),
+		.file_name                = p9_str(self->name),
+		.file_owner_uid           = p9_str(self->u_name),
+		.file_owner_gid           = p9_str(self->g_name),
+		.file_last_modified_uid   = p9_str(self->m_name),
 		.file_extension           = p9_nulstr,
-		.file_owner_n_uid         = file->metadata.u_num,
-		.file_owner_n_gid         = file->metadata.g_num,
-		.file_last_modified_n_uid = file->metadata.m_num,
+		.file_owner_n_uid         = self->u_num,
+		.file_owner_n_gid         = self->g_num,
+		.file_last_modified_n_uid = self->m_num,
 	};
 }
 
-static struct lib9p_srv_file *static_dir_dopen(struct lib9p_srv_ctx *ctx, struct lib9p_srv_file *_dir,
+static implements_lib9p_srv_file *static_dir_dopen(implements_lib9p_srv_file *_self, struct lib9p_srv_ctx *ctx,
                                                char *childname) {
+	struct static_dir *self = VCALL_SELF(struct static_dir, implements_lib9p_srv_file, _self);
+	assert(self);
 	assert(ctx);
-	struct static_dir *dir = (struct static_dir *)_dir;
-	assert(dir);
 
-	for (size_t i = 0; dir->members[i]; i++) {
-		struct lib9p_srv_file *filep = dir->members[i];
-		struct lib9p_stat stat = filep->vtable->stat(ctx, filep);
+	for (size_t i = 0; self->members[i]; i++) {
+		implements_lib9p_srv_file *filep = self->members[i];
+		struct lib9p_stat stat = VCALL(filep, stat, ctx);
 		if (lib9p_ctx_has_error(&ctx->basectx))
 			break;
 		lib9p_assert_stat(stat);
@@ -105,30 +107,30 @@ static struct lib9p_srv_file *static_dir_dopen(struct lib9p_srv_ctx *ctx, struct
 	return NULL;
 }
 
-static struct lib9p_srv_file *static_dir_dcreate(struct lib9p_srv_ctx *ctx, struct lib9p_srv_file *_dir,
+static implements_lib9p_srv_file *static_dir_dcreate(implements_lib9p_srv_file *_self, struct lib9p_srv_ctx *ctx,
                                                  char *UNUSED(childname),
                                                  lib9p_dm_t UNUSED(perm), lib9p_o_t UNUSED(flags)) {
+	struct static_dir *self = VCALL_SELF(struct static_dir, implements_lib9p_srv_file, _self);
+	assert(self);
 	assert(ctx);
-	struct static_dir *dir = (struct static_dir *)_dir;
-	assert(dir);
 
 	lib9p_error(&ctx->basectx, LINUX_EROFS, "read-only part of filesystem");
 	return NULL;
 }
 
-static size_t static_dir_dread(struct lib9p_srv_ctx *ctx, struct lib9p_srv_file *_dir,
+static size_t static_dir_dread(implements_lib9p_srv_file *_self, struct lib9p_srv_ctx *ctx,
                                uint8_t *buf,
                                uint32_t byte_count,
                                size_t _obj_offset) {
+	struct static_dir *self = VCALL_SELF(struct static_dir, implements_lib9p_srv_file, _self);
+	assert(self);
 	assert(ctx);
-	struct static_dir *dir = (struct static_dir *)_dir;
-	assert(dir);
 
 	uint32_t byte_offset = 0;
 	size_t obj_offset = _obj_offset;
-	while (dir->members[obj_offset]) {
-		struct lib9p_srv_file *filep = dir->members[obj_offset];
-		struct lib9p_stat stat = filep->vtable->stat(ctx, filep);
+	while (self->members[obj_offset]) {
+		implements_lib9p_srv_file *filep = self->members[obj_offset];
+		struct lib9p_stat stat = VCALL(filep, stat, ctx);
 		if (lib9p_ctx_has_error(&ctx->basectx))
 			break;
 		lib9p_assert_stat(stat);
@@ -147,13 +149,13 @@ static size_t static_dir_dread(struct lib9p_srv_ctx *ctx, struct lib9p_srv_file
 }
 
 struct lib9p_srv_file_vtable static_dir_vtable = {
-	.clone   = static_metadata_clone,
-	.free    = static_metadata_free,
+	.clone   = static_common_clone,
+	.free    = static_common_free,
 
-	.io      = static_metadata_io,
+	.io      = static_common_io,
 	.stat    = static_dir_stat,
-	.wstat   = static_metadata_wstat,
-	.remove  = static_metadata_remove,
+	.wstat   = static_common_wstat,
+	.remove  = static_common_remove,
 
 	.dopen   = static_dir_dopen,
 	.dcreate = static_dir_dcreate,
@@ -166,16 +168,18 @@ struct lib9p_srv_file_vtable static_dir_vtable = {
 static inline size_t static_file_size(struct static_file *file) {
 	assert(file);
 
+#if __x86_64__
 	assert(file->data_start);
+#endif
 	if (!file->data_end)
 		return file->data_size;
 	return (size_t)((uintptr_t)file->data_end - (uintptr_t)file->data_start);
 }
 
-static struct lib9p_stat static_file_stat(struct lib9p_srv_ctx *ctx, struct lib9p_srv_file *_file) {
+static struct lib9p_stat static_file_stat(implements_lib9p_srv_file *_self, struct lib9p_srv_ctx *ctx) {
+	struct static_file *self = VCALL_SELF(struct static_file, implements_lib9p_srv_file, _self);
+	assert(self);
 	assert(ctx);
-	struct static_file *file = (struct static_file *)_file;
-	assert(file);
 
 	return (struct lib9p_stat){
 		.kern_type                      = 0,
@@ -183,32 +187,32 @@ static struct lib9p_stat static_file_stat(struct lib9p_srv_ctx *ctx, struct lib9
 		.file_qid                       = {
 			.type = LIB9P_QT_FILE,
 			.vers = 1,
-			.path = file->metadata.pathnum,
+			.path = self->pathnum,
 		},
-		.file_mode                = file->metadata.perm & 0444,
-		.file_atime               = file->metadata.atime,
-		.file_mtime               = file->metadata.mtime,
-		.file_size                = (uint64_t)static_file_size(file),
-		.file_name                = p9_str(file->metadata.name),
-		.file_owner_uid           = p9_str(file->metadata.u_name),
-		.file_owner_gid           = p9_str(file->metadata.g_name),
-		.file_last_modified_uid   = p9_str(file->metadata.m_name),
+		.file_mode                = self->perm & 0444,
+		.file_atime               = self->atime,
+		.file_mtime               = self->mtime,
+		.file_size                = (uint64_t)static_file_size(self),
+		.file_name                = p9_str(self->name),
+		.file_owner_uid           = p9_str(self->u_name),
+		.file_owner_gid           = p9_str(self->g_name),
+		.file_last_modified_uid   = p9_str(self->m_name),
 		.file_extension           = p9_nulstr,
-		.file_owner_n_uid         = file->metadata.u_num,
-		.file_owner_n_gid         = file->metadata.g_num,
-		.file_last_modified_n_uid = file->metadata.m_num,
+		.file_owner_n_uid         = self->u_num,
+		.file_owner_n_gid         = self->g_num,
+		.file_last_modified_n_uid = self->m_num,
 	};
 }
 
-static uint32_t static_file_pread(struct lib9p_srv_ctx *ctx, struct lib9p_srv_file *_file,
+static uint32_t static_file_pread(implements_lib9p_srv_file *_self, struct lib9p_srv_ctx *ctx,
                                 void *buf,
                                 uint32_t byte_count,
                                 uint64_t byte_offset) {
+	struct static_file *self = VCALL_SELF(struct static_file, implements_lib9p_srv_file, _self);
+	assert(self);
 	assert(ctx);
-	struct static_file *file = (struct static_file *)_file;
-	assert(file);
 
-	size_t data_size = static_file_size(file);
+	size_t data_size = static_file_size(self);
 
 	if (byte_offset > (uint64_t)data_size) {
 		lib9p_error(&ctx->basectx,
@@ -220,18 +224,18 @@ static uint32_t static_file_pread(struct lib9p_srv_ctx *ctx, struct lib9p_srv_fi
 	size_t end_off = beg_off + (size_t)byte_count;
 	if (end_off > data_size)
 		end_off = data_size;
-	memcpy(buf, &file->data_start[beg_off], end_off-beg_off);
+	memcpy(buf, &self->data_start[beg_off], end_off-beg_off);
 	return (uint32_t)(end_off-beg_off);
 }
 
 struct lib9p_srv_file_vtable static_file_vtable = {
-	.clone   = static_metadata_clone,
-	.free    = static_metadata_free,
+	.clone   = static_common_clone,
+	.free    = static_common_free,
 
-	.io      = static_metadata_io,
+	.io      = static_common_io,
 	.stat    = static_file_stat,
-	.wstat   = static_metadata_wstat,
-	.remove  = static_metadata_remove,
+	.wstat   = static_common_wstat,
+	.remove  = static_common_remove,
 
 	.pread   = static_file_pread,
 	.pwrite  = NULL,
diff --git a/cmd/srv9p/static9p.h b/cmd/srv9p/static9p.h
index 92f5909..98b85a2 100644
--- a/cmd/srv9p/static9p.h
+++ b/cmd/srv9p/static9p.h
@@ -9,8 +9,8 @@
 
 #include <lib9p/srv.h>
 
-struct static_metadata {
-	struct lib9p_srv_file	 header;
+typedef struct {
+	implements_lib9p_srv_file;
 
 	char                    *u_name;
 	uint32_t                 u_num;
@@ -23,10 +23,10 @@ struct static_metadata {
 	char                    *name;
 	lib9p_dm_t               perm;
 	uint32_t                 atime, mtime;
-};
+} _static_common;
 
 struct static_dir {
-	struct static_metadata   metadata;
+	_static_common;
 
 	/* NULL-terminated */
 	struct lib9p_srv_file   *members[];
@@ -34,7 +34,7 @@ struct static_dir {
 
 
 struct static_file {
-	struct static_metadata   metadata;
+	_static_common;
 
 	char                    *data_start; /* must not be NULL */
 	char                    *data_end;   /* may be NULL, in which case data_size is used */