X-Git-Url: http://git.ozlabs.org/?p=ccan;a=blobdiff_plain;f=ccan%2Fio%2Fio.c;h=a58b3f01a71f7526dba3f4e69fb987d8ebaea703;hp=325db7872153952895b60d5b6dc4c99f1cb9fe0a;hb=5a510ed5696255910fd42adb47d7c1ffa728a116;hpb=0a2fd289c7bf57d9fc35ad6af36df4bcc694f361

diff --git a/ccan/io/io.c b/ccan/io/io.c
index 325db787..a58b3f01 100644
--- a/ccan/io/io.c
+++ b/ccan/io/io.c
@@ -1,4 +1,4 @@
-/* Licensed under BSD-MIT - see LICENSE file for details */
+/* Licensed under LGPLv2.1+ - see LICENSE file for details */
 #include "io.h"
 #include "backend.h"
 #include <sys/types.h>
@@ -8,27 +8,142 @@
 #include <errno.h>
 #include <stdlib.h>
 #include <assert.h>
+#include <poll.h>
+#include <unistd.h>
+#include <fcntl.h>
 
 void *io_loop_return;
 
+struct io_alloc io_alloc = {
+	malloc, realloc, free
+};
+
+#ifdef DEBUG
+/* Set to skip the next plan. */
+bool io_plan_nodebug;
+/* The current connection to apply plan to. */
+struct io_conn *current;
+/* User-defined function to select which connection(s) to debug. */
+bool (*io_debug_conn)(struct io_conn *conn);
+/* Set when we wake up an connection we are debugging. */
+bool io_debug_wakeup;
+
+struct io_plan io_debug(struct io_plan plan)
+{
+	struct io_conn *ready = NULL;
+
+	if (io_plan_nodebug) {
+		io_plan_nodebug = false;
+		return plan;
+	}
+
+	if (!current || !doing_debug_on(current)) {
+		if (!io_debug_wakeup)
+			return plan;
+	}
+
+	io_debug_wakeup = false;
+	current->plan = plan;
+	backend_plan_changed(current);
+
+	/* Call back into the loop immediately. */
+	io_loop_return = do_io_loop(&ready);
+
+	if (ready) {
+		set_current(ready);
+		if (!ready->plan.next) {
+			/* Call finish function immediately. */
+			if (ready->finish) {
+				errno = ready->plan.u1.s;
+				ready->finish(ready, ready->finish_arg);
+				ready->finish = NULL;
+			}
+			backend_del_conn(ready);
+		} else {
+			/* Calls back in itself, via io_debug_io(). */
+			if (ready->plan.io(ready->fd.fd, &ready->plan) != 2)
+				abort();
+		}
+		set_current(NULL);
+	}
+
+	/* Return a do-nothing plan, so backend_plan_changed in
+	 * io_ready doesn't do anything (it's already been called). */
+	return io_idle_();
+}
+
+int io_debug_io(int ret)
+{
+	/* Cache it for debugging; current changes. */
+	struct io_conn *conn = current;
+	int saved_errno = errno;
+
+	if (!doing_debug_on(conn))
+		return ret;
+
+	/* These will all go linearly through the io_debug() path above. */
+	switch (ret) {
+	case -1:
+		/* This will call io_debug above. */
+		errno = saved_errno;
+		io_close();
+		break;
+	case 0: /* Keep going with plan. */
+		io_debug(conn->plan);
+		break;
+	case 1: /* Done: get next plan. */
+		if (timeout_active(conn))
+			backend_del_timeout(conn);
+		/* In case they call io_duplex, clear our poll flags so
+		 * both sides don't seem to be both doing read or write
+		 * (See	assert(!mask || pfd->events != mask) in poll.c) */
+		conn->plan.pollflag = 0;
+		conn->plan.next(conn, conn->plan.next_arg);
+		break;
+	default:
+		abort();
+	}
+
+	/* Normally-invalid value, used for sanity check. */
+	return 2;
+}
+
+static void debug_io_wake(struct io_conn *conn)
+{
+	/* We want linear if we wake a debugged connection, too. */
+	if (io_debug_conn && io_debug_conn(conn))
+		io_debug_wakeup = true;
+}
+
+/* Counterpart to io_plan_no_debug(), called in macros in io.h */
+static void io_plan_debug_again(void)
+{
+	io_plan_nodebug = false;
+}
+#else
+static void debug_io_wake(struct io_conn *conn)
+{
+}
+static void io_plan_debug_again(void)
+{
+}
+#endif
+
 struct io_listener *io_new_listener_(int fd,
-				     struct io_op *(*start)(struct io_conn *,
-							    void *arg),
-				     void (*finish)(struct io_conn *, void *),
+				     void (*init)(int fd, void *arg),
 				     void *arg)
 {
-	struct io_listener *l = malloc(sizeof(*l));
+	struct io_listener *l = io_alloc.alloc(sizeof(*l));
 
 	if (!l)
 		return NULL;
 
 	l->fd.listener = true;
 	l->fd.fd = fd;
-	l->fd.next = start;
-	l->fd.finish = finish;
-	l->fd.finish_arg = l->fd.next_arg = arg;
+	l->init = init;
+	l->arg = arg;
 	if (!add_listener(l)) {
-		free(l);
+		io_alloc.free(l);
 		return NULL;
 	}
 	return l;
@@ -38,192 +153,348 @@ void io_close_listener(struct io_listener *l)
 {
 	close(l->fd.fd);
 	del_listener(l);
-	free(l);
+	io_alloc.free(l);
 }
 
-struct io_conn *io_new_conn_(int fd,
-			     struct io_op *(*start)(struct io_conn *, void *),
-			     void (*finish)(struct io_conn *, void *),
-			     void *arg)
+struct io_conn *io_new_conn_(int fd, struct io_plan plan)
 {
-	struct io_conn *conn = malloc(sizeof(*conn));
+	struct io_conn *conn = io_alloc.alloc(sizeof(*conn));
+
+	io_plan_debug_again();
 
 	if (!conn)
 		return NULL;
 
 	conn->fd.listener = false;
 	conn->fd.fd = fd;
-	conn->fd.next = start;
-	conn->fd.finish = finish;
-	conn->fd.finish_arg = conn->fd.next_arg = arg;
-	conn->state = NEXT;
+	conn->plan = plan;
+	conn->finish = NULL;
+	conn->finish_arg = NULL;
+	conn->duplex = NULL;
+	conn->timeout = NULL;
 	if (!add_conn(conn)) {
-		free(conn);
+		io_alloc.free(conn);
 		return NULL;
 	}
 	return conn;
 }
 
-/* Convenient token which only we can produce. */
-static inline struct io_next *to_ionext(struct io_conn *conn)
+void io_set_finish_(struct io_conn *conn,
+		    void (*finish)(struct io_conn *, void *),
+		    void *arg)
 {
-	return (struct io_next *)conn;
+	conn->finish = finish;
+	conn->finish_arg = arg;
 }
 
-static inline struct io_op *to_ioop(enum io_state state)
+struct io_conn *io_duplex_(struct io_conn *old, struct io_plan plan)
 {
-	return (struct io_op *)(long)state;
+	struct io_conn *conn;
+
+	io_plan_debug_again();
+
+	assert(!old->duplex);
+
+	conn = io_alloc.alloc(sizeof(*conn));
+	if (!conn)
+		return NULL;
+
+	conn->fd.listener = false;
+	conn->fd.fd = old->fd.fd;
+	conn->plan = plan;
+	conn->duplex = old;
+	conn->finish = NULL;
+	conn->finish_arg = NULL;
+	conn->timeout = NULL;
+	if (!add_duplex(conn)) {
+		io_alloc.free(conn);
+		return NULL;
+	}
+	old->duplex = conn;
+	return conn;
 }
 
-static inline struct io_conn *from_ionext(struct io_next *next)
+bool io_timeout_(struct io_conn *conn, struct timespec ts,
+		 struct io_plan (*cb)(struct io_conn *, void *), void *arg)
 {
-	return (struct io_conn *)next;
+	assert(cb);
+
+	if (!conn->timeout) {
+		conn->timeout = io_alloc.alloc(sizeof(*conn->timeout));
+		if (!conn->timeout)
+			return false;
+	} else
+		assert(!timeout_active(conn));
+
+	conn->timeout->next = cb;
+	conn->timeout->next_arg = arg;
+	backend_add_timeout(conn, ts);
+	return true;
 }
 
-struct io_next *io_next_(struct io_conn *conn,
-			 struct io_op *(*next)(struct io_conn *, void *),
-			 void *arg)
+/* Returns true if we're finished. */
+static int do_write(int fd, struct io_plan *plan)
 {
-	conn->fd.next = next;
-	conn->fd.next_arg = arg;
+	ssize_t ret = write(fd, plan->u1.cp, plan->u2.s);
+	if (ret < 0)
+		return io_debug_io(-1);
 
-	return to_ionext(conn);
+	plan->u1.cp += ret;
+	plan->u2.s -= ret;
+	return io_debug_io(plan->u2.s == 0);
 }
 
 /* Queue some data to be written. */
-struct io_op *io_write(const void *data, size_t len, struct io_next *next)
+struct io_plan io_write_(const void *data, size_t len,
+			 struct io_plan (*cb)(struct io_conn *, void *),
+			 void *arg)
 {
-	struct io_conn *conn = from_ionext(next);
-	conn->u.write.buf = data;
-	conn->u.write.len = len;
-	return to_ioop(WRITE);
+	struct io_plan plan;
+
+	assert(cb);
+	plan.u1.const_vp = data;
+	plan.u2.s = len;
+	plan.io = do_write;
+	plan.next = cb;
+	plan.next_arg = arg;
+	plan.pollflag = POLLOUT;
+
+	return plan;
+}
+
+static int do_read(int fd, struct io_plan *plan)
+{
+	ssize_t ret = read(fd, plan->u1.cp, plan->u2.s);
+	if (ret <= 0)
+		return io_debug_io(-1);
+
+	plan->u1.cp += ret;
+	plan->u2.s -= ret;
+	return io_debug_io(plan->u2.s == 0);
 }
 
 /* Queue a request to read into a buffer. */
-struct io_op *io_read(void *data, size_t len, struct io_next *next)
+struct io_plan io_read_(void *data, size_t len,
+			struct io_plan (*cb)(struct io_conn *, void *),
+			void *arg)
 {
-	struct io_conn *conn = from_ionext(next);
-	conn->u.read.buf = data;
-	conn->u.read.len = len;
-	return to_ioop(READ);
+	struct io_plan plan;
+
+	assert(cb);
+	plan.u1.cp = data;
+	plan.u2.s = len;
+	plan.io = do_read;
+	plan.next = cb;
+	plan.next_arg = arg;
+	plan.pollflag = POLLIN;
+
+	return plan;
 }
 
-/* Queue a partial request to read into a buffer. */
-struct io_op *io_read_partial(void *data, size_t *len, struct io_next *next)
+static int do_read_partial(int fd, struct io_plan *plan)
 {
-	struct io_conn *conn = from_ionext(next);
-	conn->u.readpart.buf = data;
-	conn->u.readpart.lenp = len;
-	return to_ioop(READPART);
+	ssize_t ret = read(fd, plan->u1.cp, *(size_t *)plan->u2.vp);
+	if (ret <= 0)
+		return io_debug_io(-1);
+
+	*(size_t *)plan->u2.vp = ret;
+	return io_debug_io(1);
 }
 
-/* Queue a partial write request. */
-struct io_op *io_write_partial(const void *data, size_t *len, struct io_next *next)
+/* Queue a partial request to read into a buffer. */
+struct io_plan io_read_partial_(void *data, size_t *len,
+				struct io_plan (*cb)(struct io_conn *, void *),
+				void *arg)
 {
-	struct io_conn *conn = from_ionext(next);
-	conn->u.writepart.buf = data;
-	conn->u.writepart.lenp = len;
-	return to_ioop(WRITEPART);
+	struct io_plan plan;
+
+	assert(cb);
+	plan.u1.cp = data;
+	plan.u2.vp = len;
+	plan.io = do_read_partial;
+	plan.next = cb;
+	plan.next_arg = arg;
+	plan.pollflag = POLLIN;
+
+	return plan;
 }
 
-struct io_op *io_idle(struct io_conn *conn)
+static int do_write_partial(int fd, struct io_plan *plan)
 {
-	return to_ioop(IDLE);
+	ssize_t ret = write(fd, plan->u1.cp, *(size_t *)plan->u2.vp);
+	if (ret < 0)
+		return io_debug_io(-1);
+
+	*(size_t *)plan->u2.vp = ret;
+	return io_debug_io(1);
 }
 
-void io_wake_(struct io_conn *conn,
-	      struct io_op *(*next)(struct io_conn *, void *), void *arg)
+/* Queue a partial write request. */
+struct io_plan io_write_partial_(const void *data, size_t *len,
+				 struct io_plan (*cb)(struct io_conn*, void *),
+				 void *arg)
+{
+	struct io_plan plan;
+
+	assert(cb);
+	plan.u1.const_vp = data;
+	plan.u2.vp = len;
+	plan.io = do_write_partial;
+	plan.next = cb;
+	plan.next_arg = arg;
+	plan.pollflag = POLLOUT;
+
+	return plan;
+}
 
+static int already_connected(int fd, struct io_plan *plan)
 {
-	/* It might have finished, but we haven't called its finish() yet. */
-	if (conn->state == FINISHED)
-		return;
-	assert(conn->state == IDLE);
-	conn->fd.next = next;
-	conn->fd.next_arg = arg;
-	backend_set_state(conn, to_ioop(NEXT));
+	return io_debug_io(1);
 }
 
-static struct io_op *do_next(struct io_conn *conn)
+static int do_connect(int fd, struct io_plan *plan)
 {
-	return conn->fd.next(conn, conn->fd.next_arg);
+	int err, ret;
+	socklen_t len = sizeof(err);
+
+	/* Has async connect finished? */
+	ret = getsockopt(fd, SOL_SOCKET, SO_ERROR, &err, &len);
+	if (ret < 0)
+		return -1;
+
+	if (err == 0) {
+		/* Restore blocking if it was initially. */
+		fcntl(fd, F_SETFD, plan->u1.s);
+		return 1;
+	}
+	return 0;
 }
 
-struct io_op *do_writeable(struct io_conn *conn)
+struct io_plan io_connect_(int fd, const struct addrinfo *addr,
+			   struct io_plan (*cb)(struct io_conn*, void *),
+			   void *arg)
 {
-	ssize_t ret;
-	bool finished;
+	struct io_plan plan;
 
-	switch (conn->state) {
-	case WRITE:
-		ret = write(conn->fd.fd, conn->u.write.buf, conn->u.write.len);
-		if (ret < 0)
-			return io_close(conn, NULL);
-		conn->u.write.buf += ret;
-		conn->u.write.len -= ret;
-		finished = (conn->u.write.len == 0);
-		break;
-	case WRITEPART:
-		ret = write(conn->fd.fd, conn->u.writepart.buf,
-			    *conn->u.writepart.lenp);
-		if (ret < 0)
-			return io_close(conn, NULL);
-		*conn->u.writepart.lenp = ret;
-		finished = true;
-		break;
-	default:
-		/* Shouldn't happen. */
-		abort();
+	assert(cb);
+
+	plan.next = cb;
+	plan.next_arg = arg;
+
+	/* Save old flags, set nonblock if not already. */
+	plan.u1.s = fcntl(fd, F_GETFD);
+	fcntl(fd, F_SETFD, plan.u1.s | O_NONBLOCK);
+
+	/* Immediate connect can happen. */
+	if (connect(fd, addr->ai_addr, addr->ai_addrlen) == 0) {
+		/* Dummy will be called immediately. */
+		plan.pollflag = POLLOUT;
+		plan.io = already_connected;
+	} else {
+		if (errno != EINPROGRESS)
+			return io_close_();
+
+		plan.pollflag = POLLIN;
+		plan.io = do_connect;
 	}
+	return plan;
+}
 
-	if (finished)
-		return do_next(conn);
-	return to_ioop(conn->state);
+struct io_plan io_idle_(void)
+{
+	struct io_plan plan;
+
+	plan.pollflag = 0;
+	plan.io = NULL;
+	/* Never called (overridden by io_wake), but NULL means closing */
+	plan.next = (void *)io_idle_;
+
+	return plan;
 }
 
-struct io_op *do_readable(struct io_conn *conn)
+bool io_is_idle(const struct io_conn *conn)
+{
+	return conn->plan.io == NULL;
+}
+
+void io_wake_(struct io_conn *conn, struct io_plan plan)
+
 {
-	ssize_t ret;
-	bool finished;
+	io_plan_debug_again();
 
-	switch (conn->state) {
-	case READ:
-		ret = read(conn->fd.fd, conn->u.read.buf, conn->u.read.len);
-		if (ret <= 0)
-			return io_close(conn, NULL);
-		conn->u.read.buf += ret;
-		conn->u.read.len -= ret;
-		finished = (conn->u.read.len == 0);
+	/* It might be closing, but we haven't called its finish() yet. */
+	if (!conn->plan.next)
+		return;
+	/* It was idle, right? */
+	assert(!conn->plan.io);
+	conn->plan = plan;
+	backend_plan_changed(conn);
+
+	debug_io_wake(conn);
+}
+
+void io_ready(struct io_conn *conn)
+{
+	set_current(conn);
+	switch (conn->plan.io(conn->fd.fd, &conn->plan)) {
+	case -1: /* Failure means a new plan: close up. */
+		conn->plan = io_close();
+		backend_plan_changed(conn);
 		break;
-	case READPART:
-		ret = read(conn->fd.fd, conn->u.readpart.buf,
-			    *conn->u.readpart.lenp);
-		if (ret <= 0)
-			return io_close(conn, NULL);
-		*conn->u.readpart.lenp = ret;
-		finished = true;
+	case 0: /* Keep going with plan. */
 		break;
-	default:
-		/* Shouldn't happen. */
-		abort();
+	case 1: /* Done: get next plan. */
+		if (timeout_active(conn))
+			backend_del_timeout(conn);
+		/* In case they call io_duplex, clear our poll flags so
+		 * both sides don't seem to be both doing read or write
+		 * (See	assert(!mask || pfd->events != mask) in poll.c) */
+		conn->plan.pollflag = 0;
+		conn->plan = conn->plan.next(conn, conn->plan.next_arg);
+		backend_plan_changed(conn);
 	}
-
-	if (finished)
-		return do_next(conn);
-	return to_ioop(conn->state);
+	set_current(NULL);
 }
 
-/* Useful next functions. */
 /* Close the connection, we're done. */
-struct io_op *io_close(struct io_conn *conn, void *arg)
+struct io_plan io_close_(void)
 {
-	return to_ioop(FINISHED);
+	struct io_plan plan;
+
+	plan.pollflag = 0;
+	/* This means we're closing. */
+	plan.next = NULL;
+	plan.u1.s = errno;
+
+	return plan;
+}
+
+struct io_plan io_close_cb(struct io_conn *conn, void *arg)
+{
+	return io_close();
 }
 
 /* Exit the loop, returning this (non-NULL) arg. */
-struct io_op *io_break(void *arg, struct io_next *next)
+struct io_plan io_break_(void *ret, struct io_plan plan)
 {
-	io_loop_return = arg;
+	io_plan_debug_again();
+
+	assert(ret);
+	io_loop_return = ret;
 
-	return to_ioop(NEXT);
+	return plan;
+}
+
+int io_conn_fd(const struct io_conn *conn)
+{
+	return conn->fd.fd;
+}
+
+void io_set_alloc(void *(*allocfn)(size_t size),
+		  void *(*reallocfn)(void *ptr, size_t size),
+		  void (*freefn)(void *ptr))
+{
+	io_alloc.alloc = allocfn;
+	io_alloc.realloc = reallocfn;
+	io_alloc.free = freefn;
 }