Made the tty logging code pluggable, so a non-UML kernel can specify its

own output routines.

2 files changed, 40 insertions, 16 deletions

diff --git a/arch/um/kernel/tty_log.c b/arch/um/kernel/tty_log.c
index 9a849a7..2b1e8b0 100644
--- a/arch/um/kernel/tty_log.c
+++ b/arch/um/kernel/tty_log.c
@@ -90,14 +90,14 @@ void close_tty_log(int fd, void *tty)
 	close(fd);
 }
 
-static int log_chunk(int fd, char *buf, int len)
+static int log_chunk(int fd, const char *buf, int len)
 {
 	int total = 0, try, missed, n;
 	char chunk[64];
 
 	while(len > 0){
 		try = (len > sizeof(chunk)) ? sizeof(chunk) : len;
-		missed = copy_from_user_proc(chunk, buf, try);
+		missed = copy_from_user_proc(chunk, (char *) buf, try);
 		try -= missed;
 		n = write(fd, chunk, try);
 		if(n != try)
@@ -113,7 +113,7 @@ static int log_chunk(int fd, char *buf, int len)
 	return(total);
 }
 
-int write_tty_log(int fd, char *buf, int len, void *tty, int is_read)
+int write_tty_log(int fd, const char *buf, int len, void *tty, int is_read)
 {
 	struct timeval tv;
 	struct tty_log_buf data;
@@ -169,6 +169,19 @@ void log_exec(char **argv, void *tty)
 	}
 }
 
+extern void register_tty_logger(int (*opener)(void *, void *),
+				int (*writer)(int, const char *, int, 
+					      void *, int),
+				void (*closer)(int, void *));
+
+static int register_logger(void)
+{
+	register_tty_logger(open_tty_log, write_tty_log, close_tty_log);
+	return(0);
+}
+
+__uml_initcall(register_logger);
+
 static int __init set_tty_log_dir(char *name, int *add)
 {
 	tty_log_dir = name;
diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index 5c98eef..8403828 100644
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -637,8 +637,22 @@ void start_tty(struct tty_struct *tty)
 	wake_up_interruptible(&tty->write_wait);
 }
 
-extern int write_tty_log(int fd, const unsigned char *buf, int len, void *tty,
-			 int direction);
+#ifdef CONFIG_TTY_LOG
+
+int (*open_log)(void *, void *) = NULL;
+int (*write_log)(int, const char *, int, void *, int) = NULL;
+void (*close_log)(int, void *) = NULL;
+
+void register_tty_logger(int (*opener)(void *, void *),
+			 int (*writer)(int, const char *, int, void *, int),
+			 void (*closer)(int, void *))
+{
+        open_log = opener;
+	write_log = writer;
+	close_log = closer;
+}
+
+#endif
 
 static ssize_t tty_read(struct file * file, char * buf, size_t count, 
 			loff_t *ppos)
@@ -683,8 +697,8 @@ static ssize_t tty_read(struct file * file, char * buf, size_t count,
 	if (i > 0){
 		inode->i_atime = CURRENT_TIME;
 #ifdef CONFIG_TTY_LOG
-		if(tty->log_fd >= 0) 
-		  write_tty_log(tty->log_fd, buf, i, tty, 1);
+		if((tty->log_fd >= 0) && (write_log != NULL))
+			(*write_log)(tty->log_fd, buf, i, tty, 1);
 #endif
 	}
 	return i;
@@ -741,8 +755,8 @@ static inline ssize_t do_tty_write(
 		file->f_dentry->d_inode->i_mtime = CURRENT_TIME;
 		ret = written;
 #ifdef CONFIG_TTY_LOG
-		if(tty->log_fd >= 0) 
-		  write_tty_log(tty->log_fd, buf - ret, ret, tty, 0);
+		if((tty->log_fd >= 0) && (write_log != NULL))
+			(*write_log)(tty->log_fd, buf - ret, ret, tty, 0);
 #endif
 	}
 	up(&tty->atomic_write);
@@ -1054,8 +1068,6 @@ static void release_mem(struct tty_struct *tty, int idx)
 	free_tty_struct(tty);
 }
 
-extern int close_tty_log(int fd, void *tty);
-
 /*
  * Even releasing the tty structures is a tricky business.. We have
  * to be very careful that the structures are all released at the
@@ -1285,7 +1297,8 @@ static void release_dev(struct file * filp)
 	flush_scheduled_tasks();
 
 #ifdef CONFIG_TTY_LOG
-	if(tty->log_fd >= 0) close_tty_log(tty->log_fd, tty);
+	if((tty->log_fd >= 0) && (close_log != NULL))
+		(*close_log)(tty->log_fd, tty);
 #endif
 
 	/* 
@@ -1295,8 +1308,6 @@ static void release_dev(struct file * filp)
 	release_mem(tty, idx);
 }
 
-extern int open_tty_log(void *tty, void *current_tty); 
-
 /*
  * tty_open and tty_release keep up the tty count that contains the
  * number of opens done on a tty. We cannot use the inode-count, as
@@ -1450,8 +1461,8 @@ init_dev_done:
 	}
 
 #ifdef CONFIG_TTY_LOG
-	if(tty->log_fd < 0)
-	       tty->log_fd = open_tty_log(tty, current->tty);
+	if((tty->log_fd < 0) && (open_log != NULL))
+	       tty->log_fd = (*open_log)(tty, current->tty);
 #endif
 	return 0;
 }