Currently, less(1) uses K&R prototypes, which both fails to provide u…

…seful

compiler-time type checking, and also causes problems for targets where
multiple incompatible calling conventions may be selected based on argument
types.  This change switches less(1) to ANSI prototypes.

While there, we also remove use of "register", and attempt to use "const" a
bit better now that the compiler can check argument types.

Reviewed by:	cem, emaste
MFC after:	3 weeks
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D10152

contrib/less/brac.c

@@ -24,18 +24,14 @@
  * "close bracket" are given.
  */
 	public void
-match_brac(obrac, cbrac, forwdir, n)
-	register int obrac;
-	register int cbrac;
-	int forwdir;
-	int n;
+match_brac(int obrac, int cbrac, int forwdir, int n)
 {
-	register int c;
-	register int nest;
+	int c;
+	int nest;
 	POSITION pos;
-	int (*chget)();
+	int (*chget)(void);
 
-	extern int ch_forw_get(), ch_back_get();
+	extern int ch_forw_get(void), ch_back_get(void);
 
 	/*
 	 * Seek to the line containing the open bracket.

contrib/less/ch.c

@@ -144,13 +144,13 @@ static int ch_addbuf();
  * Get the character pointed to by the read pointer.
  */
 	int
-ch_get()
+ch_get(void)
 {
-	register struct buf *bp;
-	register struct bufnode *bn;
-	register int n;
-	register int slept;
-	register int h;
+	struct buf *bp;
+	struct bufnode *bn;
+	int n;
+	int slept;
+	int h;
 	POSITION pos;
 	POSITION len;
 
@@ -378,8 +378,7 @@ ch_get()
  * a single char onto an input file descriptor.
  */
 	public void
-ch_ungetchar(c)
-	int c;
+ch_ungetchar(int c)
 {
 	if (c != -1 && ch_ungotchar != -1)
 		error("ch_ungetchar overrun", NULL_PARG);
@@ -392,7 +391,7 @@ ch_ungetchar(c)
  * If we haven't read all of standard input into it, do that now.
  */
 	public void
-end_logfile()
+end_logfile(void)
 {
 	static int tried = FALSE;
 
@@ -417,10 +416,10 @@ end_logfile()
  * Write all the existing buffered data to the log file.
  */
 	public void
-sync_logfile()
+sync_logfile(void)
 {
-	register struct buf *bp;
-	register struct bufnode *bn;
+	struct buf *bp;
+	struct bufnode *bn;
 	int warned = FALSE;
 	BLOCKNUM block;
 	BLOCKNUM nblocks;
@@ -454,12 +453,11 @@ sync_logfile()
  * Determine if a specific block is currently in one of the buffers.
  */
 	static int
-buffered(block)
-	BLOCKNUM block;
+buffered(BLOCKNUM block)
 {
-	register struct buf *bp;
-	register struct bufnode *bn;
-	register int h;
+	struct buf *bp;
+	struct bufnode *bn;
+	int h;
 
 	h = BUFHASH(block);
 	FOR_BUFS_IN_CHAIN(h, bn)
@@ -476,8 +474,7 @@ buffered(block)
  * Return 0 if successful, non-zero if can't seek there.
  */
 	public int
-ch_seek(pos)
-	register POSITION pos;
+ch_seek(POSITION pos)
 {
 	BLOCKNUM new_block;
 	POSITION len;
@@ -515,7 +512,7 @@ ch_seek(pos)
  * Seek to the end of the file.
  */
 	public int
-ch_end_seek()
+ch_end_seek(void)
 {
 	POSITION len;
 
@@ -542,10 +539,10 @@ ch_end_seek()
  * Seek to the last position in the file that is currently buffered.
  */
 	public int
-ch_end_buffer_seek()
+ch_end_buffer_seek(void)
 {
-	register struct buf *bp;
-	register struct bufnode *bn;
+	struct buf *bp;
+	struct bufnode *bn;
 	POSITION buf_pos;
 	POSITION end_pos;
 
@@ -570,10 +567,10 @@ ch_end_buffer_seek()
  * beginning of the pipe is no longer buffered.
  */
 	public int
-ch_beg_seek()
+ch_beg_seek(void)
 {
-	register struct bufnode *bn;
-	register struct bufnode *firstbn;
+	struct bufnode *bn;
+	struct bufnode *firstbn;
 
 	/*
 	 * Try a plain ch_seek first.
@@ -602,7 +599,7 @@ ch_beg_seek()
  * Return the length of the file, if known.
  */
 	public POSITION
-ch_length()
+ch_length(void)
 {
 	if (thisfile == NULL)
 		return (NULL_POSITION);
@@ -619,7 +616,7 @@ ch_length()
  * Return the current position in the file.
  */
 	public POSITION
-ch_tell()
+ch_tell(void)
 {
 	if (thisfile == NULL)
 		return (NULL_POSITION);
@@ -630,9 +627,9 @@ ch_tell()
  * Get the current char and post-increment the read pointer.
  */
 	public int
-ch_forw_get()
+ch_forw_get(void)
 {
-	register int c;
+	int c;
 
 	if (thisfile == NULL)
 		return (EOI);
@@ -653,7 +650,7 @@ ch_forw_get()
  * Pre-decrement the read pointer and get the new current char.
  */
 	public int
-ch_back_get()
+ch_back_get(void)
 {
 	if (thisfile == NULL)
 		return (EOI);
@@ -676,8 +673,7 @@ ch_back_get()
  * bufspace is in units of 1024 bytes.  -1 mean no limit.
  */
 	public void
-ch_setbufspace(bufspace)
-	int bufspace;
+ch_setbufspace(int bufspace)
 {
 	if (bufspace < 0)
 		maxbufs = -1;
@@ -693,9 +689,9 @@ ch_setbufspace(bufspace)
  * Flush (discard) any saved file state, including buffer contents.
  */
 	public void
-ch_flush()
+ch_flush(void)
 {
-	register struct bufnode *bn;
+	struct bufnode *bn;
 
 	if (thisfile == NULL)
 		return;
@@ -760,10 +756,10 @@ ch_flush()
  * The buffer is added to the tail of the buffer chain.
  */
 	static int
-ch_addbuf()
+ch_addbuf(void)
 {
-	register struct buf *bp;
-	register struct bufnode *bn;
+	struct buf *bp;
+	struct bufnode *bn;
 
 	/*
 	 * Allocate and initialize a new buffer and link it 
@@ -785,9 +781,9 @@ ch_addbuf()
  *
  */
 	static void
-init_hashtbl()
+init_hashtbl(void)
 {
-	register int h;
+	int h;
 
 	for (h = 0;  h < BUFHASH_SIZE;  h++)
 	{
@@ -800,9 +796,9 @@ init_hashtbl()
  * Delete all buffers for this file.
  */
 	static void
-ch_delbufs()
+ch_delbufs(void)
 {
-	register struct bufnode *bn;
+	struct bufnode *bn;
 
 	while (ch_bufhead != END_OF_CHAIN)
 	{
@@ -818,8 +814,7 @@ ch_delbufs()
  * Is it possible to seek on a file descriptor?
  */
 	public int
-seekable(f)
-	int f;
+seekable(int f)
 {
 #if MSDOS_COMPILER
 	extern int fd0;
@@ -840,7 +835,7 @@ seekable(f)
  * This is used after an ignore_eof read, during which the EOF may change.
  */
 	public void
-ch_set_eof()
+ch_set_eof(void)
 {
 	ch_fsize = ch_fpos;
 }
@@ -850,9 +845,7 @@ ch_set_eof()
  * Initialize file state for a new file.
  */
 	public void
-ch_init(f, flags)
-	int f;
-	int flags;
+ch_init(int f, int flags)
 {
 	/*
 	 * See if we already have a filestate for this file.
@@ -891,7 +884,7 @@ ch_init(f, flags)
  * Close a filestate.
  */
 	public void
-ch_close()
+ch_close(void)
 {
 	int keepstate = FALSE;
 
@@ -934,7 +927,7 @@ ch_close()
  * Return ch_flags for the current file.
  */
 	public int
-ch_getflags()
+ch_getflags(void)
 {
 	if (thisfile == NULL)
 		return (0);