switched slider handling to a fork()ed process

input.c

@@ -19,29 +19,95 @@
 #include <fcntl.h>
 #include <errno.h>
 #include <unistd.h>
+#include <stdlib.h>
 #include <linux/input.h>
 #include "input.h"
 
+#define OUTPUT_SIZE 21
+#define CODE_IN_SAVER 10000
+#define CODE_OUT_SAVER 10001
+
 #define NUM_FDS 4
 int inputfds[4] = { -1, -1, -1, -1 };
 
-static int openInputDevice(lua_State *L) {
-#ifndef EMULATE_READER
+int findFreeFdSlot() {
 	int i;
-	const char* inputdevice = luaL_checkstring(L, 1);
-
 	for(i=0; i<NUM_FDS; i++) {
 		if(inputfds[i] == -1) {
-			inputfds[i] = open(inputdevice, O_RDONLY | O_NONBLOCK, 0);
-			if(inputfds[i] != -1) {
-				ioctl(inputfds[i], EVIOCGRAB, 1);
-				return 0;
-			} else {
-				return luaL_error(L, "error opening input device <%s>: %d", inputdevice, errno);
-			}
+			return i;
+		}
+	}
+	return -1;
+}
+
+static int openInputDevice(lua_State *L) {
+#ifndef EMULATE_READER
+	int fd;
+	const char* inputdevice = luaL_checkstring(L, 1);
+
+	fd = findFreeFdSlot();
+	if(fd == -1) {
+		return luaL_error(L, "no free slot for new input device <%s>", inputdevice);
+	}
+
+	if(!strcmp("slider",inputdevice)) {
+		/* special case: the power slider */
+		int pipefd[2];
+		int childpid;
+
+		pipe(pipefd);
+		if((childpid = fork()) == -1) {
+			return luaL_error(L, "cannot fork() slider event listener");
+		}
+		if(childpid == 0) {
+			FILE *fp;
+			char std_out[OUTPUT_SIZE] = "";
+			struct input_event ev;
+			int ret;
+			__u16 key_code = 10000;
+
+			close(pipefd[0]);
+
+			ev.type = EV_KEY;
+			ev.code = key_code;
+			ev.value = 1;
+
+			/* listen power slider events */
+			while(1) {
+				fp = popen("exec lipc-wait-event com.lab126.powerd goingToScreenSaver,outOfScreenSaver", "r");
+				if(fgets(std_out, OUTPUT_SIZE, fp) == NULL) {
+					break;
+				}
+				pclose(fp);
+				if(std_out[0] == 'g') {
+					ev.code = CODE_IN_SAVER;
+				} else if(std_out[0] == 'o') {
+					ev.code = CODE_OUT_SAVER;
+				} else {
+					printf("Unrecognized event.\n");
+				}
+				/* fill event struct */
+				gettimeofday(&ev.time, NULL);
+
+				/* generate event */
+				if(write(pipefd[1], &ev, sizeof(struct input_event)) == -1) {
+					break;
+				}
+			}
+			exit(0); /* cannot be reached?! */
+		} else {
+			close(pipefd[1]);
+			inputfds[fd] = pipefd[0];
+		}
+	} else {
+		inputfds[fd] = open(inputdevice, O_RDONLY | O_NONBLOCK, 0);
+		if(inputfds[fd] != -1) {
+			ioctl(inputfds[fd], EVIOCGRAB, 1);
+			return 0;
+		} else {
+			return luaL_error(L, "error opening input device <%s>: %d", inputdevice, errno);
 		}
 	}
-	return luaL_error(L, "no free slot for new input device <%s>", inputdevice);
 #else
 	if(SDL_Init(SDL_INIT_VIDEO) < 0) {
 		return luaL_error(L, "cannot initialize SDL.");
@@ -66,7 +132,7 @@ static int waitForInput(lua_State *L) {
 	fd_set fds;
 	struct timeval timeout;
 	int i, num, nfds;
-	int usecs = luaL_optint(L, 1, 0x7FFFFFFF);
+	int usecs = luaL_optint(L, 1, -1); // we check for <0 later
 
 	timeout.tv_sec = (usecs/1000000);
 	timeout.tv_usec = (usecs%1000000);
@@ -81,7 +147,11 @@ static int waitForInput(lua_State *L) {
 			nfds = inputfds[i] + 1;
 	}
 
-	num = select(nfds, &fds, NULL, NULL, &timeout);
+	/* when no value is given as argument, we pass
+	 * NULL to select() for the timeout value, setting no
+	 * timeout at all.
+	 */
+	num = select(nfds, &fds, NULL, NULL, (usecs < 0) ? NULL : &timeout);
 	if(num < 0) {
 		return luaL_error(L, "Waiting for input failed: %d\n", errno);
 	}

launchpad/kpdf.sh

@@ -1,19 +1,11 @@
 #!/bin/sh
-SLIDER_EVENT_PIPE="/tmp/event_slider"
 export LC_ALL="en_US.UTF-8"
 
 echo unlock > /proc/keypad
 echo unlock > /proc/fiveway
+
 cd /mnt/us/kindlepdfviewer/
+./reader.lua "$1" 2> /mnt/us/kindlepdfviewer/crash.log
 
-# create the named pipe for power slider event
-if [ ! -p $SLIDER_EVENT_PIPE ]; then
-	mkfifo $SLIDER_EVENT_PIPE
-fi
-killall slider_watcher
-./slider_watcher $SLIDER_EVENT_PIPE &
-
-./reader.lua $1 2> /mnt/us/kindlepdfviewer/crash.log
 killall -cont cvm
-killall slider_watcher
 echo 1 > /proc/eink_fb/update_display

reader.lua

@@ -69,9 +69,6 @@ function showusage()
 	print("-g, --goto=page           start reading on page")
 	print("-G, --gamma=GAMMA         set gamma correction")
 	print("                          (floating point notation, e.g. \"1.5\")")
-	print("-d, --device=DEVICE       set device specific configuration,")
-	print("                          currently one of \"kdxg\" (default), \"k3\"")
-	print("                          \"emu\" (DXG emulation)")
 	print("-h, --help                show this usage help")
 	print("")
 	print("If you give the name of a directory instead of a file path, a file")
@@ -89,22 +86,14 @@ if optarg["h"] then
 	return showusage()
 end
 
-
-if optarg["d"] == "k3" then
-	-- for now, the only difference is the additional input device
-	input.open("/dev/input/event0")
-	input.open("/dev/input/event1")
-	input.open("/dev/input/event2")
-	input.open("/tmp/event_slider")
-	setK3Keycodes()
-elseif optarg["d"] == "emu" then
+if util.isEmulated()==1 then
 	input.open("")
 	-- SDL key codes
 	setEmuKeycodes()
 else
+	input.open("slider")
 	input.open("/dev/input/event0")
 	input.open("/dev/input/event1")
-	input.open("/tmp/event_slider")
 
 	-- check if we are running on Kindle 3 (additional volume input)
 	local f=lfs.attributes("/dev/input/event2")