Initial commit.

Makefile

@@ -0,0 +1,89 @@
+UNAME_M := $(shell uname -m)
+
+ifeq ($(UNAME_M),x86_64)
+	ARCH := ARCHITECTURE_X64
+else ifneq ($(filter $(UNAME_M),i686,i386),)
+	ARCH := ARCHITECTURE_X86
+else ifneq ($(filter $(UNAME_M),aarch64 arm64),)
+	ARCH := ARCHITECTURE_ARM64
+else ifneq ($(filter $(UNAME_M),armv7l armv6l),)
+	ARCH := ARCHITECTURE_ARM32
+endif
+
+UNAME_E := $(shell [ $$(printf '\01\00' | od -An -tu2) -eq 1 ] && \
+		   echo "little" || echo "big")
+
+ifeq ($(UNAME_E),little)
+	ENDIANESS := LITTLE_ENDIAN
+else ifeq ($(UNAME_E),little)
+	ENDIANESS := BIG_ENDIAN
+endif
+
+UNAME_S := $(shell uname -s)
+
+ifeq ($(UNAME_S),Darwin)
+	OS := OS_MACOS
+else ifeq ($(UNAME_S),Linux)
+	OS := OS_LINUX
+endif
+
+CC = gcc
+
+ifeq ($(CC),clang)
+	COMP := COMPILER_CLANG
+else ifeq ($(CC),gcc)
+	COMP := COMPILER_GCC
+endif
+
+# -ansi -pedantic -pedantic-errors
+CFLAGS = -Wno-long-long -Wall -Wextra \
+		 -Wincompatible-pointer-types \
+		 -Wint-conversion -Wformat \
+		 -Wno-strict-prototypes -Wno-missing-field-initializers \
+		 -Wno-unused-function -Wno-unused-parameter -Wno-unused-variable \
+		 -Wno-unused-but-set-variable \
+		 -fno-show-column
+
+ifeq ($(COMP),COMPILER_CLANG)
+	CFLAGS += -fno-caret-diagnostics
+else ifeq ($(COMP),COMPILER_GCC)
+	CFLAGS += -fno-diagnostics-show-caret
+endif 
+
+ifeq ($(OS),OS_MACOS)
+	FLAGS = -glldb
+	INCLUDE = 
+	LIBS = 
+	FRAMEWORKS = 
+else ifeq ($(OS),OS_LINUX)
+	FLAGS = -O3 #-ggdb -DDEBUG=1 -DINTERNAL=1
+	INCLUDE = 
+	LIBS = 
+	FRAMEWORKS =
+endif
+
+EXE = hid_apple_fn_lock
+
+default: $(EXE)
+
+$(EXE): $(EXE).c
+	$(CC) $(CFLAGS) $(FLAGS) \
+		-D$(ARCH)=1 -D$(ENDIANESS)=1 -D$(OS)=1 -D$(COMP)=1 \
+		-D_DEFAULT_SOURCE -DHAVE_SHADOW_H \
+		$(INCLUDE) $^ $(LIBS) \
+		$(FRAMEWORKS) -o $@ $(ifneq $(filter $(OS), OS_MACOS OS_LINUX), \
+		/link /FORCE:MULTIPLE)
+
+watch:
+	@ while true; do \
+		inotifywait -q -q -e 'modify' . && clear && make -B; \
+	done
+
+perf:
+	perf record --call-graph dwarf ./$(EXE)
+
+run:
+	@ clear; ./$(EXE)
+
+clean:
+	@ rm -rf $(EXE) $(EXE).dSYM

hid_apple_fn_lock.c

@@ -0,0 +1,149 @@
+#include <unistd.h> /* access */
+#include <stdlib.h> /* exit */
+#include <syslog.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <errno.h>
+#include <string.h> /* strcmp */
+
+/* Kernel module entry for the Apple Human Interface Device driver. */
+#define APPLE_HID_PATH "/sys/module/hid_apple"
+
+char file_exists(const char *filename)
+{
+    return access(filename, F_OK) != -1;
+}
+
+int init_apple_hid_module()
+{
+    int fd;
+
+    if(!file_exists(APPLE_HID_PATH)) {
+        syslog(LOG_WARNING, "Apple hid module is unloaded.");
+        return -1;
+    }
+
+    fd = open(APPLE_HID_PATH"/parameters/fnmode", O_RDWR);
+    if(fd == -1) {
+        syslog(LOG_WARNING, "Failed to open %s.",
+               APPLE_HID_PATH"/parameters/fnmode");
+        return -1;
+    }
+
+    return fd;
+}
+
+int get_fn_lock()
+{
+    int fd;
+    char state;
+
+    fd = init_apple_hid_module();
+    if(fd != -1) {
+        if(read(fd, &state, 1) != 1)
+            state = '0';
+        close(fd);
+    }
+
+    return state == '2';
+}
+
+void set_fn_lock_on()
+{
+    int fd;
+
+    fd = init_apple_hid_module();
+    if(fd != -1) {
+        if(write(fd, "2", 1) != 1)
+            syslog(LOG_WARNING, "Failed to write to Apple HID driver.");
+        else
+            syslog(LOG_INFO, "Fn lock is on.");
+        close(fd);
+    }
+}
+
+void set_fn_lock_off()
+{
+    int fd = init_apple_hid_module();
+    if(fd != -1) {
+        if(write(fd, "1", 1) != 1)
+            syslog(LOG_WARNING, "Failed to write Apple HID driver.");
+        else
+            syslog(LOG_INFO, "Fn lock is off.");
+        close(fd);
+    }
+}
+
+void daemonize()
+{
+    close(0);
+    close(1);
+    close(2);
+    open("/dev/null", O_RDONLY); /* stdin */
+    open("/dev/null", O_WRONLY); /* stdout */
+    open("/dev/null", O_WRONLY); /* stderr */
+    chdir("/");
+    int pid = fork();
+    if(pid > 0)
+        exit(0);
+    setsid();
+    pid = fork();
+    if(pid > 0)
+        exit(0);
+}
+
+#if 1
+static volatile sig_atomic_t n = 0;
+
+void usr1hdl(int sig)
+{
+    int save_errno = errno;
+    signal(SIGUSR1, usr1hdl);
+    n = 0;
+    errno = save_errno;
+}
+
+void termhdl(int sig)
+{
+    int save_errno = errno;
+    signal(SIGTERM, termhdl);
+    n = 1;
+    errno = save_errno;
+}
+#endif
+
+int main(int argc, char *argv[])
+{
+    /*daemonize();*/
+
+    signal(SIGUSR1, usr1hdl);
+    signal(SIGTERM, termhdl);
+
+    openlog("hid_apple_fn_lock", 0, LOG_USER);
+    syslog(LOG_INFO, "Daemon started, pid == %d", getpid());
+
+    uid_t euid = geteuid();
+    if(euid != 0) {
+        syslog(LOG_WARNING, "Must have root priviliges. Quitting...");
+        return 1;
+    }
+
+    for(;;) {
+        pause();
+        if(n == 0) {
+            if(get_fn_lock())
+                set_fn_lock_off();
+            else
+                set_fn_lock_on();
+        } else if(n == 1) {
+            syslog(LOG_INFO, "Shutting down...");
+            break;
+        } else {
+            /* ignore */
+        }
+    }
+
+    closelog();
+
+    return 0;
+}

sv/hid_apple_fn_lock/log/run

@@ -0,0 +1,3 @@
+#!/bin/sh
+
+exec chpst -u igor svlogd -tt /opt/hid_apple_fn_lock/logs

sv/hid_apple_fn_lock/run

@@ -0,0 +1,4 @@
+#!/bin/sh -e
+
+exec 2>&1
+exec chpst -u igor /usr/local/bin/hid_apple_fn_lock