*initHEADmaster

1 files changed, 699 insertions, 0 deletions

diff --git a/source/3rd-party/SDL2/src/core/linux/SDL_evdev.c b/source/3rd-party/SDL2/src/core/linux/SDL_evdev.c
new file mode 100644
index 0000000..5443c21
--- /dev/null
+++ b/source/3rd-party/SDL2/src/core/linux/SDL_evdev.c
@@ -0,0 +1,699 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2018 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+#include "../../SDL_internal.h"
+
+#ifdef SDL_INPUT_LINUXEV
+
+/* This is based on the linux joystick driver */
+/* References: https://www.kernel.org/doc/Documentation/input/input.txt 
+ *             https://www.kernel.org/doc/Documentation/input/event-codes.txt
+ *             /usr/include/linux/input.h
+ *             The evtest application is also useful to debug the protocol
+ */
+
+#include "SDL_evdev.h"
+#include "SDL_evdev_kbd.h"
+
+#include <sys/stat.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <linux/input.h>
+
+#include "SDL.h"
+#include "SDL_assert.h"
+#include "SDL_endian.h"
+#include "SDL_scancode.h"
+#include "../../events/SDL_events_c.h"
+#include "../../events/scancodes_linux.h" /* adds linux_scancode_table */
+#include "../../core/linux/SDL_udev.h"
+
+/* These are not defined in older Linux kernel headers */
+#ifndef SYN_DROPPED
+#define SYN_DROPPED 3
+#endif
+#ifndef ABS_MT_SLOT
+#define ABS_MT_SLOT         0x2f
+#define ABS_MT_POSITION_X   0x35
+#define ABS_MT_POSITION_Y   0x36
+#define ABS_MT_TRACKING_ID  0x39
+#endif
+
+typedef struct SDL_evdevlist_item
+{
+    char *path;
+    int fd;
+
+    /* TODO: use this for every device, not just touchscreen */
+    int out_of_sync;
+
+    /* TODO: expand on this to have data for every possible class (mouse,
+       keyboard, touchpad, etc.). Also there's probably some things in here we
+       can pull out to the SDL_evdevlist_item i.e. name */
+    int is_touchscreen;
+    struct {
+        char* name;
+
+        int min_x, max_x, range_x;
+        int min_y, max_y, range_y;
+
+        int max_slots;
+        int current_slot;
+        struct {
+            enum {
+                EVDEV_TOUCH_SLOTDELTA_NONE = 0,
+                EVDEV_TOUCH_SLOTDELTA_DOWN,
+                EVDEV_TOUCH_SLOTDELTA_UP,
+                EVDEV_TOUCH_SLOTDELTA_MOVE
+            } delta;
+            int tracking_id;
+            int x, y;
+        } * slots;
+    } * touchscreen_data;
+
+    struct SDL_evdevlist_item *next;
+} SDL_evdevlist_item;
+
+typedef struct SDL_EVDEV_PrivateData
+{
+    int ref_count;
+    int num_devices;
+    SDL_evdevlist_item *first;
+    SDL_evdevlist_item *last;
+    SDL_EVDEV_keyboard_state *kbd;
+} SDL_EVDEV_PrivateData;
+
+#undef _THIS
+#define _THIS SDL_EVDEV_PrivateData *_this
+static _THIS = NULL;
+
+static SDL_Scancode SDL_EVDEV_translate_keycode(int keycode);
+static void SDL_EVDEV_sync_device(SDL_evdevlist_item *item);
+static int SDL_EVDEV_device_removed(const char *dev_path);
+
+#if SDL_USE_LIBUDEV
+static int SDL_EVDEV_device_added(const char *dev_path, int udev_class);
+static void SDL_EVDEV_udev_callback(SDL_UDEV_deviceevent udev_type, int udev_class,
+    const char *dev_path);
+#endif /* SDL_USE_LIBUDEV */
+
+static Uint8 EVDEV_MouseButtons[] = {
+    SDL_BUTTON_LEFT,            /*  BTN_LEFT        0x110 */
+    SDL_BUTTON_RIGHT,           /*  BTN_RIGHT       0x111 */
+    SDL_BUTTON_MIDDLE,          /*  BTN_MIDDLE      0x112 */
+    SDL_BUTTON_X1,              /*  BTN_SIDE        0x113 */
+    SDL_BUTTON_X2,              /*  BTN_EXTRA       0x114 */
+    SDL_BUTTON_X2 + 1,          /*  BTN_FORWARD     0x115 */
+    SDL_BUTTON_X2 + 2,          /*  BTN_BACK        0x116 */
+    SDL_BUTTON_X2 + 3           /*  BTN_TASK        0x117 */
+};
+
+int
+SDL_EVDEV_Init(void)
+{
+    if (_this == NULL) {
+        _this = (SDL_EVDEV_PrivateData*)SDL_calloc(1, sizeof(*_this));
+        if (_this == NULL) {
+            return SDL_OutOfMemory();
+        }
+
+#if SDL_USE_LIBUDEV
+        if (SDL_UDEV_Init() < 0) {
+            SDL_free(_this);
+            _this = NULL;
+            return -1;
+        }
+
+        /* Set up the udev callback */
+        if (SDL_UDEV_AddCallback(SDL_EVDEV_udev_callback) < 0) {
+            SDL_UDEV_Quit();
+            SDL_free(_this);
+            _this = NULL;
+            return -1;
+        }
+
+        /* Force a scan to build the initial device list */
+        SDL_UDEV_Scan();
+#else
+        /* TODO: Scan the devices manually, like a caveman */
+#endif /* SDL_USE_LIBUDEV */
+
+        _this->kbd = SDL_EVDEV_kbd_init();
+    }
+
+    _this->ref_count += 1;
+
+    return 0;
+}
+
+void
+SDL_EVDEV_Quit(void)
+{
+    if (_this == NULL) {
+        return;
+    }
+
+    _this->ref_count -= 1;
+
+    if (_this->ref_count < 1) {
+#if SDL_USE_LIBUDEV
+        SDL_UDEV_DelCallback(SDL_EVDEV_udev_callback);
+        SDL_UDEV_Quit();
+#endif /* SDL_USE_LIBUDEV */
+
+        SDL_EVDEV_kbd_quit(_this->kbd);
+
+        /* Remove existing devices */
+        while(_this->first != NULL) {
+            SDL_EVDEV_device_removed(_this->first->path);
+        }
+
+        SDL_assert(_this->first == NULL);
+        SDL_assert(_this->last == NULL);
+        SDL_assert(_this->num_devices == 0);
+
+        SDL_free(_this);
+        _this = NULL;
+    }
+}
+
+#if SDL_USE_LIBUDEV
+static void SDL_EVDEV_udev_callback(SDL_UDEV_deviceevent udev_event, int udev_class,
+    const char* dev_path)
+{
+    if (dev_path == NULL) {
+        return;
+    }
+
+    switch(udev_event) {
+    case SDL_UDEV_DEVICEADDED:
+        if (!(udev_class & (SDL_UDEV_DEVICE_MOUSE | SDL_UDEV_DEVICE_KEYBOARD |
+            SDL_UDEV_DEVICE_TOUCHSCREEN)))
+            return;
+
+        SDL_EVDEV_device_added(dev_path, udev_class);
+        break;  
+    case SDL_UDEV_DEVICEREMOVED:
+        SDL_EVDEV_device_removed(dev_path);
+        break;
+    default:
+        break;
+    }
+}
+#endif /* SDL_USE_LIBUDEV */
+
+void 
+SDL_EVDEV_Poll(void)
+{
+    struct input_event events[32];
+    int i, j, len;
+    SDL_evdevlist_item *item;
+    SDL_Scancode scan_code;
+    int mouse_button;
+    SDL_Mouse *mouse;
+    float norm_x, norm_y;
+
+    if (!_this) {
+        return;
+    }
+
+#if SDL_USE_LIBUDEV
+    SDL_UDEV_Poll();
+#endif
+
+    mouse = SDL_GetMouse();
+
+    for (item = _this->first; item != NULL; item = item->next) {
+        while ((len = read(item->fd, events, (sizeof events))) > 0) {
+            len /= sizeof(events[0]);
+            for (i = 0; i < len; ++i) {
+                /* special handling for touchscreen, that should eventually be
+                   used for all devices */
+                if (item->out_of_sync && item->is_touchscreen &&
+                    events[i].type == EV_SYN && events[i].code != SYN_REPORT) {
+                    break;
+                }
+
+                switch (events[i].type) {
+                case EV_KEY:
+                    if (events[i].code >= BTN_MOUSE && events[i].code < BTN_MOUSE + SDL_arraysize(EVDEV_MouseButtons)) {
+                        mouse_button = events[i].code - BTN_MOUSE;
+                        if (events[i].value == 0) {
+                            SDL_SendMouseButton(mouse->focus, mouse->mouseID, SDL_RELEASED, EVDEV_MouseButtons[mouse_button]);
+                        } else if (events[i].value == 1) {
+                            SDL_SendMouseButton(mouse->focus, mouse->mouseID, SDL_PRESSED, EVDEV_MouseButtons[mouse_button]);
+                        }
+                        break;
+                    }
+
+                    /* Probably keyboard */
+                    scan_code = SDL_EVDEV_translate_keycode(events[i].code);
+                    if (scan_code != SDL_SCANCODE_UNKNOWN) {
+                        if (events[i].value == 0) {
+                            SDL_SendKeyboardKey(SDL_RELEASED, scan_code);
+                        } else if (events[i].value == 1 || events[i].value == 2 /* key repeated */) {
+                            SDL_SendKeyboardKey(SDL_PRESSED, scan_code);
+                        }
+                    }
+                    SDL_EVDEV_kbd_keycode(_this->kbd, events[i].code, events[i].value);
+                    break;
+                case EV_ABS:
+                    switch(events[i].code) {
+                    case ABS_MT_SLOT:
+                        if (!item->is_touchscreen) /* FIXME: temp hack */
+                            break;
+                        item->touchscreen_data->current_slot = events[i].value;
+                        break;
+                    case ABS_MT_TRACKING_ID:
+                        if (!item->is_touchscreen) /* FIXME: temp hack */
+                            break;
+                        if (events[i].value >= 0) {
+                            item->touchscreen_data->slots[item->touchscreen_data->current_slot].tracking_id = events[i].value;
+                            item->touchscreen_data->slots[item->touchscreen_data->current_slot].delta = EVDEV_TOUCH_SLOTDELTA_DOWN;
+                        } else {
+                            item->touchscreen_data->slots[item->touchscreen_data->current_slot].delta = EVDEV_TOUCH_SLOTDELTA_UP;
+                        }
+                        break;
+                    case ABS_MT_POSITION_X:
+                        if (!item->is_touchscreen) /* FIXME: temp hack */
+                            break;
+                        item->touchscreen_data->slots[item->touchscreen_data->current_slot].x = events[i].value;
+                        if (item->touchscreen_data->slots[item->touchscreen_data->current_slot].delta == EVDEV_TOUCH_SLOTDELTA_NONE) {
+                            item->touchscreen_data->slots[item->touchscreen_data->current_slot].delta = EVDEV_TOUCH_SLOTDELTA_MOVE;
+                        }
+                        break;
+                    case ABS_MT_POSITION_Y:
+                        if (!item->is_touchscreen) /* FIXME: temp hack */
+                            break;
+                        item->touchscreen_data->slots[item->touchscreen_data->current_slot].y = events[i].value;
+                        if (item->touchscreen_data->slots[item->touchscreen_data->current_slot].delta == EVDEV_TOUCH_SLOTDELTA_NONE) {
+                            item->touchscreen_data->slots[item->touchscreen_data->current_slot].delta = EVDEV_TOUCH_SLOTDELTA_MOVE;
+                        }
+                        break;
+                    case ABS_X:
+                        if (item->is_touchscreen) /* FIXME: temp hack */
+                            break;
+                        SDL_SendMouseMotion(mouse->focus, mouse->mouseID, SDL_FALSE, events[i].value, mouse->y);
+                        break;
+                    case ABS_Y:
+                        if (item->is_touchscreen) /* FIXME: temp hack */
+                            break;
+                        SDL_SendMouseMotion(mouse->focus, mouse->mouseID, SDL_FALSE, mouse->x, events[i].value);
+                        break;
+                    default:
+                        break;
+                    }
+                    break;
+                case EV_REL:
+                    switch(events[i].code) {
+                    case REL_X:
+                        SDL_SendMouseMotion(mouse->focus, mouse->mouseID, SDL_TRUE, events[i].value, 0);
+                        break;
+                    case REL_Y:
+                        SDL_SendMouseMotion(mouse->focus, mouse->mouseID, SDL_TRUE, 0, events[i].value);
+                        break;
+                    case REL_WHEEL:
+                        SDL_SendMouseWheel(mouse->focus, mouse->mouseID, 0, events[i].value, SDL_MOUSEWHEEL_NORMAL);
+                        break;
+                    case REL_HWHEEL:
+                        SDL_SendMouseWheel(mouse->focus, mouse->mouseID, events[i].value, 0, SDL_MOUSEWHEEL_NORMAL);
+                        break;
+                    default:
+                        break;
+                    }
+                    break;
+                case EV_SYN:
+                    switch (events[i].code) {
+                    case SYN_REPORT:
+                        if (!item->is_touchscreen) /* FIXME: temp hack */
+                            break;
+
+                        for(j = 0; j < item->touchscreen_data->max_slots; j++) {
+                            norm_x = (float)(item->touchscreen_data->slots[j].x - item->touchscreen_data->min_x) /
+                                (float)item->touchscreen_data->range_x;
+                            norm_y = (float)(item->touchscreen_data->slots[j].y - item->touchscreen_data->min_y) /
+                                (float)item->touchscreen_data->range_y;
+
+                            switch(item->touchscreen_data->slots[j].delta) {
+                            case EVDEV_TOUCH_SLOTDELTA_DOWN:
+                                SDL_SendTouch(item->fd, item->touchscreen_data->slots[j].tracking_id, SDL_TRUE, norm_x, norm_y, 1.0f);
+                                item->touchscreen_data->slots[j].delta = EVDEV_TOUCH_SLOTDELTA_NONE;
+                                break;
+                            case EVDEV_TOUCH_SLOTDELTA_UP:
+                                SDL_SendTouch(item->fd, item->touchscreen_data->slots[j].tracking_id, SDL_FALSE, norm_x, norm_y, 1.0f);
+                                item->touchscreen_data->slots[j].tracking_id = -1;
+                                item->touchscreen_data->slots[j].delta = EVDEV_TOUCH_SLOTDELTA_NONE;
+                                break;
+                            case EVDEV_TOUCH_SLOTDELTA_MOVE:
+                                SDL_SendTouchMotion(item->fd, item->touchscreen_data->slots[j].tracking_id, norm_x, norm_y, 1.0f);
+                                item->touchscreen_data->slots[j].delta = EVDEV_TOUCH_SLOTDELTA_NONE;
+                                break;
+                            default:
+                                break;
+                            }
+                        }
+
+                        if (item->out_of_sync)
+                            item->out_of_sync = 0;
+                        break;
+                    case SYN_DROPPED:
+                        if (item->is_touchscreen)
+                            item->out_of_sync = 1;
+                        SDL_EVDEV_sync_device(item);
+                        break;
+                    default:
+                        break;
+                    }
+                    break;
+                }
+            }
+        }    
+    }
+}
+
+static SDL_Scancode
+SDL_EVDEV_translate_keycode(int keycode)
+{
+    SDL_Scancode scancode = SDL_SCANCODE_UNKNOWN;
+
+    if (keycode < SDL_arraysize(linux_scancode_table))
+        scancode = linux_scancode_table[keycode];
+
+    if (scancode == SDL_SCANCODE_UNKNOWN) {
+        SDL_Log("The key you just pressed is not recognized by SDL. To help "
+            "get this fixed, please report this to the SDL forums/mailing list "
+            "<https://discourse.libsdl.org/> EVDEV KeyCode %d", keycode);
+    }
+
+    return scancode;
+}
+
+#ifdef SDL_USE_LIBUDEV
+static int
+SDL_EVDEV_init_touchscreen(SDL_evdevlist_item* item)
+{
+    int ret, i;
+    char name[64];
+    struct input_absinfo abs_info;
+
+    if (!item->is_touchscreen)
+        return 0;
+
+    item->touchscreen_data = SDL_calloc(1, sizeof(*item->touchscreen_data));
+    if (item->touchscreen_data == NULL)
+        return SDL_OutOfMemory();
+
+    ret = ioctl(item->fd, EVIOCGNAME(sizeof(name)), name);
+    if (ret < 0) {
+        SDL_free(item->touchscreen_data);
+        return SDL_SetError("Failed to get evdev touchscreen name");
+    }
+
+    item->touchscreen_data->name = SDL_strdup(name);
+    if (item->touchscreen_data->name == NULL) {
+        SDL_free(item->touchscreen_data);
+        return SDL_OutOfMemory();
+    }
+
+    ret = ioctl(item->fd, EVIOCGABS(ABS_MT_POSITION_X), &abs_info);
+    if (ret < 0) {
+        SDL_free(item->touchscreen_data->name);
+        SDL_free(item->touchscreen_data);
+        return SDL_SetError("Failed to get evdev touchscreen limits");
+    }
+    item->touchscreen_data->min_x = abs_info.minimum;
+    item->touchscreen_data->max_x = abs_info.maximum;
+    item->touchscreen_data->range_x = abs_info.maximum - abs_info.minimum;
+
+    ret = ioctl(item->fd, EVIOCGABS(ABS_MT_POSITION_Y), &abs_info);
+    if (ret < 0) {
+        SDL_free(item->touchscreen_data->name);
+        SDL_free(item->touchscreen_data);
+        return SDL_SetError("Failed to get evdev touchscreen limits");
+    }
+    item->touchscreen_data->min_y = abs_info.minimum;
+    item->touchscreen_data->max_y = abs_info.maximum;
+    item->touchscreen_data->range_y = abs_info.maximum - abs_info.minimum;
+
+    ret = ioctl(item->fd, EVIOCGABS(ABS_MT_SLOT), &abs_info);
+    if (ret < 0) {
+        SDL_free(item->touchscreen_data->name);
+        SDL_free(item->touchscreen_data);
+        return SDL_SetError("Failed to get evdev touchscreen limits");
+    }
+    item->touchscreen_data->max_slots = abs_info.maximum + 1;
+
+    item->touchscreen_data->slots = SDL_calloc(
+        item->touchscreen_data->max_slots,
+        sizeof(*item->touchscreen_data->slots));
+    if (item->touchscreen_data->slots == NULL) {
+        SDL_free(item->touchscreen_data->name);
+        SDL_free(item->touchscreen_data);
+        return SDL_OutOfMemory();
+    }
+
+    for(i = 0; i < item->touchscreen_data->max_slots; i++) {
+        item->touchscreen_data->slots[i].tracking_id = -1;
+    }
+
+    ret = SDL_AddTouch(item->fd, /* I guess our fd is unique enough */
+        item->touchscreen_data->name);
+    if (ret < 0) {
+        SDL_free(item->touchscreen_data->slots);
+        SDL_free(item->touchscreen_data->name);
+        SDL_free(item->touchscreen_data);
+        return ret;
+    }
+
+    return 0;
+}
+#endif /* SDL_USE_LIBUDEV */
+
+static void
+SDL_EVDEV_destroy_touchscreen(SDL_evdevlist_item* item) {
+    if (!item->is_touchscreen)
+        return;
+
+    SDL_DelTouch(item->fd);
+    SDL_free(item->touchscreen_data->slots);
+    SDL_free(item->touchscreen_data->name);
+    SDL_free(item->touchscreen_data);
+}
+
+static void
+SDL_EVDEV_sync_device(SDL_evdevlist_item *item) 
+{
+#ifdef EVIOCGMTSLOTS
+    int i, ret;
+    struct input_absinfo abs_info;
+    /*
+     * struct input_mt_request_layout {
+     *     __u32 code;
+     *     __s32 values[num_slots];
+     * };
+     *
+     * this is the structure we're trying to emulate
+     */
+    __u32* mt_req_code;
+    __s32* mt_req_values;
+    size_t mt_req_size;
+
+    /* TODO: sync devices other than touchscreen */
+    if (!item->is_touchscreen)
+        return;
+
+    mt_req_size = sizeof(*mt_req_code) +
+        sizeof(*mt_req_values) * item->touchscreen_data->max_slots;
+
+    mt_req_code = SDL_calloc(1, mt_req_size);
+    if (mt_req_code == NULL) {
+        return;
+    }
+
+    mt_req_values = (__s32*)mt_req_code + 1;
+
+    *mt_req_code = ABS_MT_TRACKING_ID;
+    ret = ioctl(item->fd, EVIOCGMTSLOTS(mt_req_size), mt_req_code);
+    if (ret < 0) {
+        SDL_free(mt_req_code);
+        return;
+    }
+    for(i = 0; i < item->touchscreen_data->max_slots; i++) {
+        /*
+         * This doesn't account for the very edge case of the user removing their
+         * finger and replacing it on the screen during the time we're out of sync,
+         * which'll mean that we're not going from down -> up or up -> down, we're
+         * going from down -> down but with a different tracking id, meaning we'd
+         * have to tell SDL of the two events, but since we wait till SYN_REPORT in
+         * SDL_EVDEV_Poll to tell SDL, the current structure of this code doesn't
+         * allow it. Lets just pray to God it doesn't happen.
+         */
+        if (item->touchscreen_data->slots[i].tracking_id < 0 &&
+            mt_req_values[i] >= 0) {
+            item->touchscreen_data->slots[i].tracking_id = mt_req_values[i];
+            item->touchscreen_data->slots[i].delta = EVDEV_TOUCH_SLOTDELTA_DOWN;
+        } else if (item->touchscreen_data->slots[i].tracking_id >= 0 &&
+            mt_req_values[i] < 0) {
+            item->touchscreen_data->slots[i].tracking_id = -1;
+            item->touchscreen_data->slots[i].delta = EVDEV_TOUCH_SLOTDELTA_UP;
+        }
+    }
+
+    *mt_req_code = ABS_MT_POSITION_X;
+    ret = ioctl(item->fd, EVIOCGMTSLOTS(mt_req_size), mt_req_code);
+    if (ret < 0) {
+        SDL_free(mt_req_code);
+        return;
+    }
+    for(i = 0; i < item->touchscreen_data->max_slots; i++) {
+        if (item->touchscreen_data->slots[i].tracking_id >= 0 &&
+            item->touchscreen_data->slots[i].x != mt_req_values[i]) {
+            item->touchscreen_data->slots[i].x = mt_req_values[i];
+            if (item->touchscreen_data->slots[i].delta ==
+                EVDEV_TOUCH_SLOTDELTA_NONE) {
+                item->touchscreen_data->slots[i].delta =
+                    EVDEV_TOUCH_SLOTDELTA_MOVE;
+            }
+        }
+    }
+
+    *mt_req_code = ABS_MT_POSITION_Y;
+    ret = ioctl(item->fd, EVIOCGMTSLOTS(mt_req_size), mt_req_code);
+    if (ret < 0) {
+        SDL_free(mt_req_code);
+        return;
+    }
+    for(i = 0; i < item->touchscreen_data->max_slots; i++) {
+        if (item->touchscreen_data->slots[i].tracking_id >= 0 &&
+            item->touchscreen_data->slots[i].y != mt_req_values[i]) {
+            item->touchscreen_data->slots[i].y = mt_req_values[i];
+            if (item->touchscreen_data->slots[i].delta ==
+                EVDEV_TOUCH_SLOTDELTA_NONE) {
+                item->touchscreen_data->slots[i].delta =
+                    EVDEV_TOUCH_SLOTDELTA_MOVE;
+            }
+        }
+    }
+
+    ret = ioctl(item->fd, EVIOCGABS(ABS_MT_SLOT), &abs_info);
+    if (ret < 0) {
+        SDL_free(mt_req_code);
+        return;
+    }
+    item->touchscreen_data->current_slot = abs_info.value;
+
+    SDL_free(mt_req_code);
+
+#endif /* EVIOCGMTSLOTS */
+}
+
+#if SDL_USE_LIBUDEV
+static int
+SDL_EVDEV_device_added(const char *dev_path, int udev_class)
+{
+    int ret;
+    SDL_evdevlist_item *item;
+
+    /* Check to make sure it's not already in list. */
+    for (item = _this->first; item != NULL; item = item->next) {
+        if (SDL_strcmp(dev_path, item->path) == 0) {
+            return -1;  /* already have this one */
+        }
+    }
+
+    item = (SDL_evdevlist_item *) SDL_calloc(1, sizeof (SDL_evdevlist_item));
+    if (item == NULL) {
+        return SDL_OutOfMemory();
+    }
+
+    item->fd = open(dev_path, O_RDONLY | O_NONBLOCK);
+    if (item->fd < 0) {
+        SDL_free(item);
+        return SDL_SetError("Unable to open %s", dev_path);
+    }
+
+    item->path = SDL_strdup(dev_path);
+    if (item->path == NULL) {
+        close(item->fd);
+        SDL_free(item);
+        return SDL_OutOfMemory();
+    }
+
+    if (udev_class & SDL_UDEV_DEVICE_TOUCHSCREEN) {
+        item->is_touchscreen = 1;
+
+        if ((ret = SDL_EVDEV_init_touchscreen(item)) < 0) {
+            close(item->fd);
+            SDL_free(item);
+            return ret;
+        }
+    }
+
+    if (_this->last == NULL) {
+        _this->first = _this->last = item;
+    } else {
+        _this->last->next = item;
+        _this->last = item;
+    }
+
+    SDL_EVDEV_sync_device(item);
+
+    return _this->num_devices++;
+}
+#endif /* SDL_USE_LIBUDEV */
+
+static int
+SDL_EVDEV_device_removed(const char *dev_path)
+{
+    SDL_evdevlist_item *item;
+    SDL_evdevlist_item *prev = NULL;
+
+    for (item = _this->first; item != NULL; item = item->next) {
+        /* found it, remove it. */
+        if (SDL_strcmp(dev_path, item->path) == 0) {
+            if (prev != NULL) {
+                prev->next = item->next;
+            } else {
+                SDL_assert(_this->first == item);
+                _this->first = item->next;
+            }
+            if (item == _this->last) {
+                _this->last = prev;
+            }
+            if (item->is_touchscreen) {
+                SDL_EVDEV_destroy_touchscreen(item);
+            }
+            close(item->fd);
+            SDL_free(item->path);
+            SDL_free(item);
+            _this->num_devices--;
+            return 0;
+        }
+        prev = item;
+    }
+
+    return -1;
+}
+
+
+#endif /* SDL_INPUT_LINUXEV */
+
+/* vi: set ts=4 sw=4 expandtab: */