ccan/io: save errno on io_close, for finish functions.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

diff --git a/ccan/io/io.c b/ccan/io/io.c
index 352afe33e87638ed638729f7e56f91f37ea1db71..b6ae56acf027a7c0a46b3a2c9027d07d7bd9617b 100644 (file)
--- a/ccan/io/io.c
+++ b/ccan/io/io.c
@@ -325,6 +325,7 @@ struct io_plan io_close(void)
        plan.pollflag = 0;
        /* This means we're closing. */
        plan.next = NULL;
+       plan.u.close.saved_errno = errno;
 
        io_plan_debug(&plan);
        return plan;

diff --git a/ccan/io/io.h b/ccan/io/io.h
index 8199bda9802050f747440f66ec1da97f987fcb47..6553e7ab29b93de5bc1bd5118f63745f81b5279b 100644 (file)
--- a/ccan/io/io.h
+++ b/ccan/io/io.h
@@ -38,6 +38,9 @@ struct io_plan {
                        const char *buf;
                        size_t *lenp;
                } writepart;
+               struct {
+                       int saved_errno;
+               } close;
                struct {
                        void *p;
                        size_t len;
@@ -84,7 +87,8 @@ struct io_conn *io_new_conn_(int fd, struct io_plan plan);
  * @arg: the argument to @finish.
  *
  * @finish will be called when an I/O operation fails, or you call
- * io_close() on the connection.
+ * io_close() on the connection.  errno will be set to the value
+ * after the failed I/O, or at the call to io_close().
  */
 #define io_set_finish(conn, finish, arg)                               \
        io_set_finish_((conn),                                          \

diff --git a/ccan/io/poll.c b/ccan/io/poll.c
index 42ed67ad278a0c870c9c4a98baa015eb0ed4e60a..3ed6321bc7f4a0309ca2c2a55f41ab17ae328511 100644 (file)
--- a/ccan/io/poll.c
+++ b/ccan/io/poll.c
@@ -7,6 +7,7 @@
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <limits.h>
+#include <errno.h>
 
 static size_t num_fds = 0, max_fds = 0, num_closing = 0, num_waiting = 0;
 static struct pollfd *pollfds = NULL;
@@ -173,8 +174,10 @@ bool add_duplex(struct io_conn *c)
 
 static void del_conn(struct io_conn *conn)
 {
-       if (conn->finish)
+       if (conn->finish) {
+               errno = conn->plan.u.close.saved_errno;
                conn->finish(conn, conn->finish_arg);
+       }
        if (timeout_active(conn))
                backend_del_timeout(conn);
        free(conn->timeout);
@@ -341,6 +344,7 @@ void *io_loop(void)
                        } else if (events & (POLLHUP|POLLNVAL|POLLERR)) {
                                r--;
                                set_current(c);
+                               errno = EBADF;
                                set_plan(c, io_close());
                                if (c->duplex) {
                                        set_current(c->duplex);

diff --git a/ccan/io/test/run-18-errno-DEBUG.c b/ccan/io/test/run-18-errno-DEBUG.c
new file mode 100644 (file)
index 0000000..bfa6615
--- /dev/null
+++ b/ccan/io/test/run-18-errno-DEBUG.c
@@ -0,0 +1,8 @@
+#define DEBUG
+#define PORT "64018"
+#define main real_main
+int real_main(void);
+#include "run-18-errno.c"
+#undef main
+static bool always_debug(struct io_conn *conn) { return true; }
+int main(void) { io_debug = always_debug; return real_main(); }

diff --git a/ccan/io/test/run-18-errno.c b/ccan/io/test/run-18-errno.c
new file mode 100644 (file)
index 0000000..985a322
--- /dev/null
+++ b/ccan/io/test/run-18-errno.c
@@ -0,0 +1,120 @@
+#include <ccan/io/io.h>
+/* Include the C files directly. */
+#include <ccan/io/poll.c>
+#include <ccan/io/io.c>
+#include <ccan/tap/tap.h>
+#include <sys/wait.h>
+#include <stdio.h>
+
+#ifndef PORT
+#define PORT "65018"
+#endif
+
+static void finish_100(struct io_conn *conn, int *state)
+{
+       ok1(errno == 100);
+       ok1(*state == 1);
+       (*state)++;
+}
+
+static void finish_EBADF(struct io_conn *conn, int *state)
+{
+       ok1(errno == EBADF);
+       ok1(*state == 3);
+       (*state)++;
+       io_break(state + 1, io_close());
+}
+
+static void init_conn(int fd, int *state)
+{
+       if (*state == 0) {
+               (*state)++;
+               errno = 100;
+               io_set_finish(io_new_conn(fd, io_close()), finish_100, state);
+       } else {
+               ok1(*state == 2);
+               (*state)++;
+               close(fd);
+               errno = 0;
+               io_set_finish(io_new_conn(fd, io_read(state, 0,
+                                                     io_close_cb, NULL)),
+                             finish_EBADF, state);
+       }
+}
+
+static int make_listen_fd(const char *port, struct addrinfo **info)
+{
+       int fd, on = 1;
+       struct addrinfo *addrinfo, hints;
+
+       memset(&hints, 0, sizeof(hints));
+       hints.ai_family = AF_UNSPEC;
+       hints.ai_socktype = SOCK_STREAM;
+       hints.ai_flags = AI_PASSIVE;
+       hints.ai_protocol = 0;
+
+       if (getaddrinfo(NULL, port, &hints, &addrinfo) != 0)
+               return -1;
+
+       fd = socket(addrinfo->ai_family, addrinfo->ai_socktype,
+                   addrinfo->ai_protocol);
+       if (fd < 0)
+               return -1;
+
+       setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
+       if (bind(fd, addrinfo->ai_addr, addrinfo->ai_addrlen) != 0) {
+               close(fd);
+               return -1;
+       }
+       if (listen(fd, 1) != 0) {
+               close(fd);
+               return -1;
+       }
+       *info = addrinfo;
+       return fd;
+}
+
+int main(void)
+{
+       int state = 0;
+       struct addrinfo *addrinfo;
+       struct io_listener *l;
+       int fd;
+
+       /* This is how many tests you plan to run */
+       plan_tests(12);
+       fd = make_listen_fd(PORT, &addrinfo);
+       ok1(fd >= 0);
+       l = io_new_listener(fd, init_conn, &state);
+       ok1(l);
+       fflush(stdout);
+       if (!fork()) {
+               io_close_listener(l);
+               fd = socket(addrinfo->ai_family, addrinfo->ai_socktype,
+                           addrinfo->ai_protocol);
+               if (fd < 0)
+                       exit(1);
+               if (connect(fd, addrinfo->ai_addr, addrinfo->ai_addrlen) != 0)
+                       exit(2);
+               close(fd);
+               fd = socket(addrinfo->ai_family, addrinfo->ai_socktype,
+                           addrinfo->ai_protocol);
+               if (fd < 0)
+                       exit(3);
+               if (connect(fd, addrinfo->ai_addr, addrinfo->ai_addrlen) != 0)
+                       exit(4);
+               close(fd);
+               freeaddrinfo(addrinfo);
+               exit(0);
+       }
+       freeaddrinfo(addrinfo);
+       ok1(io_loop() == &state + 1);
+       ok1(state == 4);
+       io_close_listener(l);
+       ok1(wait(&state));
+       ok1(WIFEXITED(state));
+       ok1(WEXITSTATUS(state) == 0);
+
+       /* This exits depending on whether all tests passed */
+       return exit_status();
+}