Input: Minor logging tweaks (#1549)

Mainly, pass human-readable errors to Lua, not just a raw errno.

input/input-cervantes.h

@@ -41,7 +41,7 @@ static void generateFakeEvent(int pipefd[2]) {
 
     int re = ue_init_listener(&listener);
     if (re < 0) {
-        fprintf(stderr, "[ko-input]: Failed to initialize libue listener, err: %d\n", re);
+        fprintf(stderr, "[ko-input]: Failed to initialize libue listener (%d)\n", re);
         return;
     }
 

input/input-kobo.h

@@ -33,14 +33,14 @@ static void sendEvent(int fd, struct input_event* ev)
 }
 
 // Using strtol right is *fun*...
-static int safe_strtol(const char* str)
+static int strtol_d(const char* str)
 {
     char* endptr;
     errno = 0;
     long int val = strtol(str, &endptr, 10);
     if (errno || endptr == str || *endptr || (int) val != val) {
         // strtol failure || no digits were found || trailing garbage || cast truncation
-        return -1;
+        return -1; // this will conveniently never match a real evdev number ;).
     }
 
     return (int) val;
@@ -104,12 +104,12 @@ static void generateFakeEvent(int pipefd[2])
                 case UEVENT_ACTION_ADD:
                     ev.code = CODE_FAKE_USB_DEVICE_PLUGGED_IN;
                     // Pass along the evdev number
-                    ev.value = safe_strtol(uev.devname + sizeof("input/event") - 1U); // i.e., start right after the t of event
+                    ev.value = strtol_d(uev.devname + sizeof("input/event") - 1U); // i.e., start right after the t of event
                     sendEvent(pipefd[1], &ev);
                     break;
                 case UEVENT_ACTION_REMOVE:
                     ev.code = CODE_FAKE_USB_DEVICE_PLUGGED_OUT;
-                    ev.value = safe_strtol(uev.devname + sizeof("input/event") - 1U);
+                    ev.value = strtol_d(uev.devname + sizeof("input/event") - 1U);
                     sendEvent(pipefd[1], &ev);
                     break;
                 default:

input/input-pocketbook.h

@@ -242,16 +242,16 @@ static int startInkViewMain(lua_State *L, size_t fd_idx, const char *inputdevice
 
     inputfds[fd_idx] = open(inputdevice, O_RDWR | O_NONBLOCK);
     if (inputfds[fd_idx] == -1) {
-        return luaL_error(L, "error opening input device <%s>: %d\n", inputdevice, errno);
+        return luaL_error(L, "Error opening input device <%s>: %s", inputdevice, strerror(errno));
     }
 
     if (pthread_attr_init(&thread_attr) != 0) {
-        return luaL_error(L, "error initializing event listener thread attributes: %d", errno);
+        return luaL_error(L, "Error initializing event listener thread attributes: %s", strerror(errno));
     }
 
     pthread_attr_setdetachstate(&thread_attr, PTHREAD_CREATE_DETACHED);
     if (pthread_create(&thread, &thread_attr, runInkViewThread, 0) == -1) {
-        return luaL_error(L, "error creating event listener thread: %d", errno);
+        return luaL_error(L, "Error creating event listener thread: %s", strerror(errno));
     }
     pthread_attr_destroy(&thread_attr);
     return 0;

input/input-remarkable.h

@@ -105,7 +105,7 @@ static void generateFakeEventRM1(int pipefd) {
 
     re = ue_init_listener(&listener);
     if (re < 0) {
-        fprintf(stderr, "[remarkable-fake-event] Failed to initilize libue listener, err: %d\n", re);
+        fprintf(stderr, "[remarkable-fake-event] Failed to initilize libue listener (%d)\n", re);
         return;
     }
 

input/input-sony-prstux.h

@@ -78,7 +78,7 @@ static void generateFakeEvent(int pipefd[2]) {
 
     re = ue_init_listener(&listener);
     if (re < 0) {
-        fprintf(stderr, "[sony-prstux-fake-event] Failed to initilize libue listener, err: %d\n", re);
+        fprintf(stderr, "[sony-prstux-fake-event] Failed to initilize libue listener (%d)\n", re);
         return;
     }
 

input/input.c

@@ -112,7 +112,7 @@ static int openInputDevice(lua_State* L)
 #if defined(KINDLE_LEGACY)
         // pipe2 requires Linux 2.6.27 & glibc 2.9...
         if (pipe(pipefd) == -1) {
-            return luaL_error(L, "Cannot create fake event generator communication pipe (pipe(): %d)", errno);
+            return luaL_error(L, "Cannot create fake event generator communication pipe (pipe(): %s)", strerror(errno));
         }
 
         // Which means we need the fcntl dance like with open below...
@@ -124,13 +124,13 @@ static int openInputDevice(lua_State* L)
         }
 #else
         if (pipe2(pipefd, O_NONBLOCK | O_CLOEXEC) == -1) {
-            return luaL_error(L, "Cannot create fake event generator communication pipe (pipe2(): %d)", errno);
+            return luaL_error(L, "Cannot create fake event generator communication pipe (pipe2(): %s)", strerror(errno));
         }
 #endif
 
         pid_t childpid;
         if ((childpid = fork()) == -1) {
-            return luaL_error(L, "Cannot fork() fake event generator (%d)", errno);
+            return luaL_error(L, "Cannot fork() fake event generator: %s", strerror(errno));
         }
         if (childpid == 0) {
             // Deliver SIGTERM to child when parent dies.
@@ -166,7 +166,7 @@ static int openInputDevice(lua_State* L)
             fcntl(inputfds[fd_idx], F_SETFD, fdflags | FD_CLOEXEC);
 #endif
         } else {
-            return luaL_error(L, "Error opening input device <%s>: %d", inputdevice, errno);
+            return luaL_error(L, "Error opening input device <%s>: %s", inputdevice, strerror(errno));
         }
     }
 
@@ -198,7 +198,7 @@ static int closeInputDevice(ssize_t fd_idx_to_close)
     inputfds[--fd_idx] = -1;
 
     computeNfds();
-    printf("[ko-input] Closed input device with idx=%zd, fd=%d\n", fd_idx_to_close, fd);
+    printf("[ko-input] Closed input device with fd: %d @ idx: %zd\n", fd, fd_idx_to_close);
 
     return 0;
 }
@@ -234,7 +234,7 @@ static int fakeTapInput(lua_State* L)
 
     int inputfd = open(inputdevice, O_WRONLY | O_NONBLOCK);
     if (inputfd == -1) {
-        return luaL_error(L, "Cannot open input device <%s>: %d", inputdevice, errno);
+        return luaL_error(L, "Error opening tap injection input device <%s>: %s", inputdevice, strerror(errno));
     }
 
     // Pop function args, now that we're done w/ inputdevice

input/libue.h

@@ -88,6 +88,7 @@ struct uevent_listener
 #define ERR_LISTENER_RECV         -4
 #define ERR_PARSE_UDEV            -1
 #define ERR_PARSE_INVALID_HDR     -2
+// NOTE: This is a *prefix* match, str just needs to *begin* with const_str for it to match!
 #define UE_STR_EQ(str, const_str) (strncmp((str), (const_str), sizeof(const_str) - 1U) == 0)
 
 enum uevent_action