Make keyboard path a compile time constant

2 files changed, 28 insertions, 23 deletions

diff --git a/Makefile b/Makefile
index 3d41a4a..8548dbc 100644
--- a/Makefile
+++ b/Makefile
@@ -8,6 +8,7 @@ UXN_HEAD  := $(BASE_UXN)/src/uxn.h
 TAL_SRC   ?= $(BASE_UXN)/projects/examples/devices/screen.tal
 UXN_ROM   ?= $(BUILD_DIR)/rom.rom
 UXN_ASM   ?= $(BUILD_DIR)/uxnasm
+KBD_PATH  ?= /dev/input/event1
 
 CC        ?= cc
 CFLAGS    := -Wall -Wextra -pedantic
@@ -29,7 +30,7 @@ endif
 main: $(BIN)
 
 $(BIN): $(SRC_MAIN) $(BUILD_DIR) $(UXN_HEAD)
-        $(CC) $(CFLAGS) -o $(BIN) $(SRC_MAIN)
+        $(CC) $(CFLAGS) -o $(BIN) $(SRC_MAIN) -DKBD_PATH=\"$(KBD_PATH)\"
 
 $(BUILD_DIR):
         mkdir -p $(BUILD_DIR)
diff --git a/src/main.c b/src/main.c
index 445fb17..aac3211 100644
--- a/src/main.c
+++ b/src/main.c
@@ -33,35 +33,39 @@ time_elapsed(Time since){
     return (now.tv_sec - since.tv_sec) * 1e9 + (now.tv_nsec - since.tv_nsec);
 }
 
-typedef struct Keyboard {
-    int fd;
+typedef struct Input {
+    int kb_fd;
     char map[KEY_MAX / 8 + 1];
     u8 controller;
-} Keyboard;
+} Input;
 
-static Keyboard keyboard;
+static Input input;
 
 void
 init_input(void) {
-    memset(&keyboard, 0, sizeof(Keyboard));
-
-    const char *dev = "/dev/input/by-id/usb-Apple_Inc._Magic_Keyboard_with_Numeric_Keypad_F0T0167000DHTHKAD-if01-event-kbd";
-    keyboard.fd = open(dev, O_RDONLY);
-    if (keyboard.fd == -1) {
-        // TODO: should this be a warning and still work for applications that
-        //       don't require a keyboard?
+    memset(&input, 0, sizeof(input));
+    input.kb_fd = -1;
+
+    const char *dev = KBD_PATH;
+    input.kb_fd = open(dev, O_RDONLY);
+    if (input.kb_fd == -1) {
+        // NOTE: Some applications may not require a keyboard so this is
+        // optional, but we are still displaying an error.
         fprintf(stderr, "error: no couldn't open keyboard %s: %s.\n", dev, strerror(errno));
-        exit(EXIT_FAILURE);
     }
 }
 
 void
 poll_keyboard(void) {
+    if (input.kb_fd == -1) {
+        return;
+    }
+
     char map[KEY_MAX / 8 + 1];
     memset(map, 0, sizeof(map));
-    ioctl(keyboard.fd, EVIOCGKEY(sizeof(map)), map);
+    ioctl(input.kb_fd, EVIOCGKEY(sizeof(map)), map);
     for (size_t i = 0; i < sizeof(map); i++) {
-        keyboard.map[i] |= map[i];
+        input.map[i] |= map[i];
     }
 }
 
@@ -72,9 +76,9 @@ handle_keyboard(void) {
     // bool ctrl_mod = false;
     // bool alt_mod = false;
     // bool meta_mod = false;
-    for (size_t i = 0; i < sizeof(keyboard.map); i++) {
+    for (size_t i = 0; i < sizeof(input.map); i++) {
         for (size_t j = 0; j < 8; j++) {
-            char key = keyboard.map[i] & (1 << j);
+            char key = input.map[i] & (1 << j);
             if (key) {
                 char key_code = i * 8 + j;
                 switch (key_code) {
@@ -94,9 +98,9 @@ handle_keyboard(void) {
 
     // Handle normal keys.
     u8 controller_now = 0;
-    for (size_t i = 0; i < sizeof(keyboard.map); i++) {
+    for (size_t i = 0; i < sizeof(input.map); i++) {
         for (size_t j = 0; j < 8; j++) {
-            char key = keyboard.map[i] & (1 << j);
+            char key = input.map[i] & (1 << j);
             if (key) {
                 char key_code = i * 8 + j;
                 // Normal keys.
@@ -200,15 +204,15 @@ handle_keyboard(void) {
         }
     }
 
-    if (controller_now != keyboard.controller) {
+    if (controller_now != input.controller) {
         devctrl->dat[2] = controller_now;
         uxn_eval(&u, mempeek16(devctrl->dat, 0));
-        keyboard.controller = controller_now;
+        input.controller = controller_now;
     }
 
-    // Reset keyboard state.
+    // Reset input state.
     devctrl->dat[3] = 0;
-    memset(keyboard.map, 0, sizeof(keyboard.map));
+    memset(input.map, 0, sizeof(input.map));
 }
 
 void