devman: isseekable()

src/include/kernel/devman.h

@@ -7,17 +7,20 @@
 #define MAJOR_ZERO 2
 #define MAJOR_NULL 3
 #define MAJOR_FULL 4
+#define MAJOR_FB 5
 
 typedef struct{
 	int (*read)(int* error, int minor, void* buff, size_t count, size_t offset);
 	int (*write)(int* error, int minor, void* buff, size_t count, size_t offset);
 	int (*isatty)(int minor);
+	int (*isseekable)(int minor, size_t* seekmax);
 } devcalls;
 
 int devman_read(int *error, int dev, void* buff, size_t count, size_t offset);
 int devman_write(int *error, int dev, void* buff, size_t count, size_t offset);
 int devman_newdevice(char* name, int type, int major, int minor, devcalls* calls);
 int devman_isatty(int dev);
+int devman_isseekable(int dev, size_t* seekmax);
 void devman_init();
 
 #endif

src/sys/devman.c

@@ -56,6 +56,16 @@ int devman_isatty(int dev){
 	
 }
 
+int devman_isseekable(int dev, size_t* max){
+
+        if(major(dev) > highestmajor)
+                return ENOTTY;
+
+        return majorcalls[major(dev)]->isseekable(minor(dev), max);
+
+}
+
+
 void devman_init(){
 	
 	devfs_init();

src/sys/pseudodevs/full.c

@@ -17,8 +17,13 @@ static int isatty(int minor){
 	return ENOTTY;
 }
 
+static int isseekable(int minor, size_t* max){
+        *max = ~(size_t)0;
+        return 0;
+}
+
 static devcalls calls = {
-	read, write, isatty
+	read, write, isatty, isseekable
 };
 
 void fulldev_init(){

src/sys/pseudodevs/null.c

@@ -16,8 +16,13 @@ static int isatty(int minor){
 	return ENOTTY;
 }
 
+static int isseekable(int minor, size_t* max){
+        *max = ~(size_t)0;
+        return 0;
+}
+
 static devcalls calls = {
-	read, write, isatty
+	read, write, isatty, isseekable
 };
 
 void nulldev_init(){

src/sys/pseudodevs/zero.c

@@ -17,8 +17,13 @@ static int isatty(int minor){
 	return ENOTTY;
 }
 
+static int isseekable(int minor, size_t* max){
+	*max = ~(size_t)0;
+	return 0;
+}
+
 static devcalls calls = {
-	read, write, isatty
+	read, write, isatty, isseekable
 };
 
 void zerodev_init(){

src/video/consoledev.c

@@ -120,10 +120,14 @@ static int write(int *error, int dev, void* buff, size_t count, size_t offset){
 	return count;
 }
 
-devcalls calls = {
-	read, write, isatty
-};
 
+static int isseekable(){
+	return ESPIPE;
+}
+
+devcalls calls = {
+	read, write, isatty, isseekable
+};
 
 void consoledev_init(){