From a744fa640c5bfc9eda37d1dcf9d18763076190a8 Mon Sep 17 00:00:00 2001
From: XANTRONIX Development <dev@xantronix.com>
Date: Sun, 9 Aug 2015 09:50:12 -0500
Subject: [PATCH] Implement patty_ax25_next_event() like I'm not a dumbass or
 some shit

---
 include/patty/ax25.h | 28 ++++++++++++++++++-------
 src/ax25.c           | 49 +++++++++++++++++++++++++++++++++++++++++---
 2 files changed, 67 insertions(+), 10 deletions(-)

diff --git a/include/patty/ax25.h b/include/patty/ax25.h
index 251c43c..4b58224 100644
--- a/include/patty/ax25.h
+++ b/include/patty/ax25.h
@@ -15,12 +15,15 @@
 #include <patty/ax25/frame.h>
 #include <patty/ax25/if.h>
 
-enum patty_ax25_event {
-    PATTY_AX25_IO_UNKNOWN,
-    PATTY_AX25_IO_RECV,
-    PATTY_AX25_IO_SEND,
-    PATTY_AX25_IO_READ,
-    PATTY_AX25_IO_WRITE
+#define PATTY_AX25_EVENT_QUEUE_SIZE 32
+
+enum patty_ax25_event_type {
+    PATTY_AX25_EVENT_UNKNOWN,
+    PATTY_AX25_EVENT_RECV,
+    PATTY_AX25_EVENT_SEND,
+    PATTY_AX25_EVENT_READ,
+    PATTY_AX25_EVENT_WRITE,
+    PATTY_AX25_EVENT_ERROR
 };
 
 enum patty_ax25_sock_status {
@@ -55,6 +58,12 @@ typedef struct _patty_ax25_sock {
     patty_ax25_address * remote;
 } patty_ax25_sock;
 
+typedef struct _patty_ax25_event {
+    enum patty_ax25_event_type type;
+
+    int fd;
+} patty_ax25_event;
+
 struct _patty_ax25 {
     patty_list * ifaces;
     patty_list * socks;
@@ -62,8 +71,13 @@ struct _patty_ax25 {
     int    unix_fdmax;
     fd_set unix_fds;
 
+    fd_set unix_fds_pending_read;
+    fd_set unix_fds_pending_write;
+    fd_set unix_fds_pending_error;
+
     patty_dict * fd_lookup;
     int          fd;
+    int          current;
 };
 
 int patty_ax25_init(patty_ax25 *ax25);
@@ -89,7 +103,7 @@ int patty_ax25_accept(patty_ax25 *ax25,
 int patty_ax25_close(patty_ax25 *ax25, int fd);
 
 int patty_ax25_next_event(patty_ax25 *ax25,
-    enum patty_ax25_event *ev);
+    patty_ax25_event *ev);
 
 int patty_ax25_recv(patty_ax25 *ax25,
     int fd, patty_ax25_frame *frame);
diff --git a/src/ax25.c b/src/ax25.c
index 664c4f0..7082d86 100644
--- a/src/ax25.c
+++ b/src/ax25.c
@@ -1,6 +1,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <errno.h>
+#include <sys/select.h>
 
 #include <patty/ax25.h>
 
@@ -19,8 +20,6 @@ int patty_ax25_init(patty_ax25 *ax25) {
         goto error_dict_new_fd_lookup;
     }
 
-    ax25->fd = 0;
-
     return 0;
 
 error_dict_new_fd_lookup:
@@ -188,6 +187,50 @@ error_fd_lookup:
     return -1;
 }
 
-int patty_ax25_next_event(patty_ax25 *ax25, enum patty_ax25_event *ev) {
+int patty_ax25_next_event(patty_ax25 *ax25, patty_ax25_event *ev) {
+    int fd;
+
+    if (ax25->current == 0) {
+        memcpy(&ax25->unix_fds_pending_read,  &ax25->unix_fds, sizeof(ax25->unix_fds));
+        memcpy(&ax25->unix_fds_pending_write, &ax25->unix_fds, sizeof(ax25->unix_fds));
+        memcpy(&ax25->unix_fds_pending_error, &ax25->unix_fds, sizeof(ax25->unix_fds));
+
+        if (select(ax25->unix_fdmax,
+          &ax25->unix_fds_pending_read,
+          &ax25->unix_fds_pending_write,
+          &ax25->unix_fds_pending_error,
+          NULL) < 0) {
+            goto error_select;
+        }
+    }
+
+    for (fd=ax25->current; fd<ax25->unix_fdmax; fd++) {
+        if (FD_ISSET(fd, &ax25->unix_fds_pending_read)) {
+            ev->type = PATTY_AX25_EVENT_RECV;
+            ev->fd   = fd;
+
+            return 0;
+        }
+
+        if (FD_ISSET(fd, &ax25->unix_fds_pending_write)) {
+            ev->type = PATTY_AX25_EVENT_SEND;
+            ev->fd   = fd;
+
+            return 0;
+        }
+
+        if (FD_ISSET(fd, &ax25->unix_fds_pending_error)) {
+            ev->type = PATTY_AX25_EVENT_ERROR;
+            ev->fd   = fd;
+
+            return 0;
+        }
+    }
+
+    ax25->current = 0;
+
     return 0;
+
+error_select:
+    return -1;
 }