Add event test utility

This change is a wrapper around libx52io to print the raw events coming
from the X52 device.

configure.ac

@@ -110,6 +110,7 @@ AC_CONFIG_FILES([ po/Makefile.in
     utils/Makefile
     utils/cli/Makefile
     utils/test/Makefile
+    utils/evtest/Makefile
     tests/Makefile
 ])
 AC_OUTPUT

utils/Makefile.am

@@ -4,5 +4,5 @@
 #
 # SPDX-License-Identifier: GPL-2.0-only WITH Classpath-exception-2.0
 
-SUBDIRS = cli test
+SUBDIRS = cli test evtest
 

utils/evtest/Makefile.am

@@ -0,0 +1,15 @@
+# Automake for x52evtest
+#
+# Copyright (C) 2012-2020 Nirenjan Krishnan (nirenjan@nirenjan.org)
+#
+# SPDX-License-Identifier: GPL-2.0-only WITH Classpath-exception-2.0
+
+ACLOCAL_AMFLAGS = -I m4
+
+bin_PROGRAMS = x52evtest
+
+# Event test utility that works similarly to the Linux evtest
+x52evtest_SOURCES = ev_test.c
+x52evtest_CFLAGS = -I $(top_srcdir)/lib/libx52io -I $(top_srcdir) -DLOCALEDIR=\"$(localedir)\" $(WARN_CFLAGS)
+x52evtest_LDFLAGS = $(WARN_LDFLAGS)
+x52evtest_LDADD = ../../lib/libx52io/libx52io.la

utils/evtest/ev_test.c

@@ -0,0 +1,134 @@
+/*
+ * Saitek X52 Pro MFD & LED driver - Event test utility
+ *
+ * Copyright (C) 2012-2020 Nirenjan Krishnan (nirenjan@nirenjan.org)
+ *
+ * SPDX-License-Identifier: GPL-2.0-only WITH Classpath-exception-2.0
+ */
+
+#include "config.h"
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <signal.h>
+#include <string.h>
+#include <unistd.h>
+#include <time.h>
+#include <sys/time.h>
+
+#include "libx52io.h"
+#include "gettext.h"
+
+/*
+Output Format
+=============
+
+Driver version is 0.0.0
+Device ID: bus 0x3 vendor 0x06a3 product 0x0762 version 0x110
+Device name: "Saitek X52 Pro Flight Control System"
+Testing ... (interrupt to exit)
+
+Event @ 1594431236.817842, ABS_X, value 512
+Event @ 1594431236.817842, ABS_Y, value 511
+Event @ 1594431236.817842, BTN_TRIGGER, value 1
+Event @ 1594431236.817842, BTN_MODE_1, value 1
+
+Event @ 1594431236.847810, BTN_MODE_1, value 0
+
+Event @ 1594431236.877802, BTN_MODE_2, value 1
+
+ */
+
+static bool exit_loop = false;
+
+static void signal_handler(int sig)
+{
+    exit_loop = true;
+}
+
+/* For i18n */
+#define _(x) gettext(x)
+int main(int argc, char **argv)
+{
+    libx52io_context *ctx;
+    libx52io_report last, curr;
+    int rc;
+    #define CHECK_RC() do { \
+        if (rc != LIBX52IO_SUCCESS) { \
+            fprintf(stderr, "%s\n", libx52io_strerror(rc)); \
+            return rc; \
+        } \
+    } while(0)
+
+    /* Initialize gettext */
+    #if ENABLE_NLS
+    setlocale(LC_ALL, "");
+    bindtextdomain(PACKAGE, LOCALEDIR);
+    textdomain(LOCALEDIR);
+    #endif
+
+    memset(&last, 0, sizeof(last));
+    memset(&curr, 0, sizeof(curr));
+
+    /* Initialize libx52io */
+    rc = libx52io_init(&ctx);
+    CHECK_RC();
+
+    /* Make sure that we have a device to connect to */
+    rc = libx52io_open(ctx);
+    CHECK_RC();
+
+    /* Set up the signal handler to terminate the loop on SIGTERM or SIGINT */
+    exit_loop = false;
+    signal(SIGTERM, signal_handler);
+    signal(SIGINT, signal_handler);
+
+    /* TODO: Print the driver version and the connected device */
+    puts(_("Testing (interrupt to exit)\n"));
+
+    /* Wait until we get an event */
+    while (!exit_loop) {
+        struct timeval tv;
+
+        /* Wait for 1 second before timing out */
+        rc = libx52io_read_timeout(ctx, &curr, 1000);
+        if (rc == LIBX52IO_ERROR_TIMEOUT) {
+            continue;
+        } else if (rc != LIBX52IO_SUCCESS) {
+            /* Some other error while reading. Abort the loop */
+            break;
+        }
+
+        /*
+         * Successful read, compare the current report against the previous
+         * one and display the result
+         */
+        if (memcmp(&last, &curr, sizeof(curr)) == 0) {
+            /* No change, ignore the output */
+            continue;
+        }
+
+        /* Get the current timeval - we don't need a timezone */
+        gettimeofday(&tv, NULL);
+        puts("");
+        for (int axis = 0; axis < LIBX52IO_AXIS_MAX; axis++) {
+            if (last.axis[axis] != curr.axis[axis]) {
+                printf(_("Event @ %ld.%09lu: %s, value %d\n"), tv.tv_sec, tv.tv_usec,
+                    libx52io_axis_to_str(axis), curr.axis[axis]);
+            }
+        }
+        for (int btn = 0; btn < LIBX52IO_BUTTON_MAX; btn++) {
+            if (last.button[btn] != curr.button[btn]) {
+                printf(_("Event @ %ld.%09lu: %s, value %d\n"), tv.tv_sec, tv.tv_usec,
+                    libx52io_button_to_str(btn), curr.button[btn]);
+            }
+        }
+
+        memcpy(&last, &curr, sizeof(curr));
+    }
+
+    /* Close and exit the libx52io library */
+    libx52io_close(ctx);
+    libx52io_exit(ctx);
+}