kernel: introduce a u_done counter set to 0 in rwsetup

We then use this to clean up psleep_flags_io and some other code. This also
saves us a few bytes

Kernel/dev/net/net_z80pack.c

@@ -214,7 +214,6 @@ void net_close(struct socket *s)
  */
 arg_t net_read(struct socket *s, uint8_t flag)
 {
-	usize_t n = 0;
 	struct sockdata *sd = s->s_priv;
 	irqflags_t irq;
 	uint8_t st;
@@ -248,20 +247,20 @@ arg_t net_read(struct socket *s, uint8_t flag)
         				break;
                         }
 			uputc(data, udata.u_base++);
-			n++;
-			if (n < udata.u_count)
+			udata.u_done++;
+			if (udata.u_done < udata.u_count)
 			        continue;
 		}
-		if (n)
+		if (udata.u_done)
 		        break;
 		s->s_iflag &= ~SI_DATA;
-		if (psleep_flags_io(&s->s_iflag, flag, &n)) {
+		if (psleep_flags_io(&s->s_iflag, flag)) {
         		irqrestore(irq);
 			return -1;
                 }
 	}
-	if (n)
-		return n;
+	if (udata.u_done)
+		return udata.u_done;
 	if (st & 0x80) {
 		err_xlate(s);
 		return -1;
@@ -275,7 +274,6 @@ arg_t net_read(struct socket *s, uint8_t flag)
  */
 arg_t net_write(struct socket * s, uint8_t flag)
 {
-	usize_t n = 0;
 	uint8_t p = 0;
 	struct sockdata *sd = s->s_priv;
 	irqflags_t irq;
@@ -298,10 +296,10 @@ arg_t net_write(struct socket * s, uint8_t flag)
 			break;
 
 		/* Good status after a write means byte ok */
-		n += p;
-		if (n == udata.u_count) {
+		udata.u_done += p;
+		if (udata.u_done == udata.u_count) {
 		        irqrestore(irq);
-			return n;
+			return udata.u_done;
                 }
 		/* Can we send more bytes ? */
 		p = 0;
@@ -315,18 +313,18 @@ arg_t net_write(struct socket * s, uint8_t flag)
 			continue;
 		}
 		s->s_iflag |= SI_THROTTLE;
-		if (psleep_flags_io(&s->s_iflag, flag, &n)) {
+		if (psleep_flags_io(&s->s_iflag, flag)) {
                         irqrestore(irq);
 			return n;
                 }
                 di();
 	}
 	/* It broke mummy ! */
         irqrestore(irq);
-	if (n) {
+	if (udata.u_done) {
 	        s->s_error = udata.u_error;
 	        udata.u_error = 0;
-		return n;
+		return udata.u_done;
         }
 	err_xlate(s);
 	if (udata.u_error == EPIPE)

Kernel/dev/z80pack/devlpr.c

@@ -18,36 +18,36 @@ int lpr_close(uint8_t minor)
     return 0;
 }
 
-static int iopoll(int sofar)
+static uint8_t iopoll(void)
 {
 	/* Ought to be a core helper for this lot ? */
 	if (need_reschedule())
 		_sched_yield();
 	if (chksigs()) {
-		if (sofar)
-			return sofar;
-		udata.u_error = EINTR;
-		return -1;
+		if (!udata.u_done) {
+			udata.u_error = EINTR;
+			udata.u_done = (usize_t)-1;
+                }
+                return 1;
 	}
 	return 0;
 }
 
 int lpr_write(uint8_t minor, uint8_t rawflag, uint8_t flag)
 {
-    int c = udata.u_count;
     char *p = udata.u_base;
     minor; rawflag; flag; // shut up compiler
 
-    while(c) {
+    while(udata.u_done < udata.u_count) {
         /* Note; on real hardware it might well be necessary to
            busy wait a bit just to get acceptable performance */
         while (lpstat != 0xFF) {
-            int n;
-            if (n = iopoll(p - udata.u_base))
-                return n;
+            if (iopoll())
+                return udata.u_done;
         }
         /* FIXME: tidy up ugetc and sysio checks globally */
         lpdata = ugetc(p++);
+        udata.u_done++;
     }
-    return (-1);
+    return udata.u_done;
 }

Kernel/devio.c

@@ -474,19 +474,19 @@ bool uninsq(struct s_queue *q, unsigned char *cp)
              Miscellaneous helpers
 **********************************************************************/
 
-int psleep_flags_io(void *p, unsigned char flags, usize_t *n)
+int psleep_flags_io(void *p, unsigned char flags)
 {
 	if (flags & O_NDELAY) {
-	        if (!*n) {
-	                *n = (usize_t)-1;
+	        if (!udata.u_done) {
+	                udata.u_done = (usize_t)-1;
 			udata.u_error = EAGAIN;
                 }
 		return -1;
 	}
 	psleep(p);
 	if (chksigs()) {
-	        if (!*n) {
-	                *n = (usize_t)-1;
+	        if (!udata.u_done) {
+	                udata.u_done = (usize_t)-1;
                         udata.u_error = EINTR;
                 }
 		return -1;
@@ -496,8 +496,16 @@ int psleep_flags_io(void *p, unsigned char flags, usize_t *n)
 
 int psleep_flags(void *p, unsigned char flags)
 {
-        usize_t dummy = 0;
-        return psleep_flags_io(p, flags, &dummy);
+	if (flags & O_NDELAY) {
+		udata.u_error = EAGAIN;
+		return -1;
+	}
+	psleep(p);
+	if (chksigs()) {
+                udata.u_error = EINTR;
+		return -1;
+	}
+	return 0;
 }
 
 void kputs(const char *p)

Kernel/include/kernel.h

@@ -21,6 +21,10 @@ From UZI by Doug Braun and UZI280 by Stefan Nitschke.
 #define NULL (void *)0
 #endif
 
+#ifndef regptr
+#define regptr
+#endif
+
 #define min(a,b) ( (a) < (b) ? (a) : (b) )
 #define max(a,b) ( (a) > (b) ? (a) : (b) )
 #define aligndown(v,a) (uint8_t*)((intptr_t)(v) & ~((a)-1))
@@ -40,8 +44,8 @@ From UZI by Doug Braun and UZI280 by Stefan Nitschke.
 #include "level2.h"
 #else
 
-#define jobcontrol_in(x,y,z)	0
-#define jobcontrol_out(x,y,z)	0
+#define jobcontrol_in(x,y)	0
+#define jobcontrol_out(x,y)	0
 #define jobcontrol_ioctl(x,y,z)	0
 
 #define limit_exceeded(x,y) (0)
@@ -516,6 +520,7 @@ typedef struct u_data {
     uint16_t	u_blkoff;	/* Offset in block */
     usize_t	u_nblock;	/* Number of blocks */
     uint8_t	*u_dptr;	/* Address for I/O */
+    usize_t	u_done;		/* Counter for driver methods */
 
 #ifdef CONFIG_LEVEL_2
     uint16_t    u_groups[NGROUP]; /* Group list */
@@ -820,7 +825,7 @@ extern bool insq(struct s_queue *q, unsigned char c);
 extern bool remq(struct s_queue *q, unsigned char *cp);
 extern void clrq(struct s_queue *q);
 extern bool uninsq(struct s_queue *q, unsigned char *cp);
-extern int psleep_flags_io(void *event, unsigned char flags, usize_t *n);
+extern int psleep_flags_io(void *event, unsigned char flags);
 extern int psleep_flags(void *event, unsigned char flags);
 extern int nxio_open(uint8_t minor, uint16_t flag);
 extern int no_open(uint8_t minor, uint16_t flag);

Kernel/inode.c

@@ -293,6 +293,7 @@ inoptr rwsetup(bool is_read, uint8_t * flag)
 	udata.u_sysio = false;	/* I/O to user data space */
 	udata.u_base = (unsigned char *) udata.u_argn1;	/* buf */
 	udata.u_count = (susize_t) udata.u_argn2;	/* nbytes */
+	udata.u_done = 0;		/* bytes done so far */
 
 	if ((ino = getinode(udata.u_argn)) == NULLINODE) {
 		/* kprintf("[WRS: rwsetup(): getinode(%x) fails]", udata.u_argn); */

Kernel/level2.c

@@ -79,28 +79,28 @@ static uint8_t jobop(uint8_t minor, uint8_t sig, struct tty *t, uint8_t ign)
 }
 
 /* For input readign with SIGTTIN blocked gets you an EIO */
-uint8_t jobcontrol_in(uint8_t minor, struct tty *t, usize_t *nread)
+uint8_t jobcontrol_in(uint8_t minor, struct tty *t)
 {
 	if (!jobop(minor, SIGTTIN, t, 0))
 		return 0;
-	if (*nread == 0) {
+	if (udata.u_done == 0) {
 		udata.u_error = EINTR;
-		*nread = (usize_t)-1;
+		udata.u_done = (usize_t)-1;
 	}
 	return 1;
 }
 
 
 /* For output ignored stop is taken to mean as write anyway */
-uint8_t jobcontrol_out(uint8_t minor, struct tty *t, usize_t *written)
+uint8_t jobcontrol_out(uint8_t minor, struct tty *t)
 {
 	if (!(t->termios.c_lflag & TOSTOP))
 		return 0;
         if (!jobop(minor, SIGTTOU, t, 1))
 		return 0;
-	if (*written == 0) {
+	if (udata.u_done == 0) {
 		udata.u_error = EINTR;
-		*written = (usize_t)-1;
+		udata.u_done = (usize_t)-1;
 	}
 	return 1;
 }

Kernel/tty.c

@@ -34,7 +34,6 @@ static void tty_selwake(uint8_t minor, uint16_t event)
 
 int tty_read(uint8_t minor, uint8_t rawflag, uint8_t flag)
 {
-	usize_t nread;
 	unsigned char c;
 	struct s_queue *q;
 	struct tty *t;
@@ -44,12 +43,12 @@ int tty_read(uint8_t minor, uint8_t rawflag, uint8_t flag)
 
 	q = &ttyinq[minor];
 	t = &ttydata[minor];
-	nread = 0;
-	while (nread < udata.u_count) {
+
+	while (udata.u_done < udata.u_count) {
 		for (;;) {
 #ifdef CONFIG_LEVEL_2		
-                        if (jobcontrol_in(minor, t, &nread))
-				return nread;
+                        if (jobcontrol_in(minor, t))
+				return udata.u_done;
 #endif				
 		        if ((t->flag & TTYF_DEAD) && (!q->q_count))
 				goto dead;
@@ -63,25 +62,25 @@ int tty_read(uint8_t minor, uint8_t rawflag, uint8_t flag)
 			if (!(t->termios.c_lflag & ICANON)) {
 			        uint8_t n = t->termios.c_cc[VTIME];
 
-				if ((nread || !n) && nread >= t->termios.c_cc[VMIN])
+				if ((udata.u_done || !n) && udata.u_done >= t->termios.c_cc[VMIN])
 					goto out;
 				if (n)
 			                udata.u_ptab->p_timeout = n + 1;
                         }
-			if (psleep_flags_io(q, flag, &nread))
+			if (psleep_flags_io(q, flag))
 			        goto out;
                         /* timer expired */
                         if (udata.u_ptab->p_timeout == 1)
                                 goto out;
 		}
 
-		++nread;
+		++udata.u_done;
 
 		/* return according to mode */
 		if (t->termios.c_lflag & ICANON) {
-			if (nread == 1 && (c == t->termios.c_cc[VEOF])) {
+			if (udata.u_done == 1 && (c == t->termios.c_cc[VEOF])) {
 				/* ^D */
-				nread = 0;
+				udata.u_done = 0;
 				break;
 			}
 			if (c == '\n' || c == t->termios.c_cc[VEOL])
@@ -92,7 +91,7 @@ int tty_read(uint8_t minor, uint8_t rawflag, uint8_t flag)
 	}
 out:
 	wakeup(&q->q_count);
-	return nread;
+	return udata.u_done;
 
 dead:
         udata.u_error = ENXIO;
@@ -102,27 +101,26 @@ int tty_read(uint8_t minor, uint8_t rawflag, uint8_t flag)
 int tty_write(uint8_t minor, uint8_t rawflag, uint8_t flag)
 {
 	struct tty *t;
-	usize_t written = 0;
 	uint8_t c;
 
 	used(rawflag);
 
 	t = &ttydata[minor];
 
-	while (udata.u_count-- != 0) {
+	while (udata.u_done != udata.u_count) {
 		for (;;) {	/* Wait on the ^S/^Q flag */
 #ifdef CONFIG_LEVEL_2		
-	                if (jobcontrol_out(minor, t, &written))
-				return written;
+	                if (jobcontrol_out(minor, t))
+				return udata.u_done;
 #endif				
 		        if (t->flag & TTYF_DEAD) {
 			        udata.u_error = ENXIO;
 			        return -1;
 			}
 			if (!(t->flag & TTYF_STOP))
 				break;
-			if (psleep_flags_io(&t->flag, flag, &written))
-				return written;
+			if (psleep_flags_io(&t->flag, flag))
+				return udata.u_done;
 		}
 		if (!(t->flag & TTYF_DISCARD)) {
 			if (udata.u_sysio)
@@ -141,9 +139,9 @@ int tty_write(uint8_t minor, uint8_t rawflag, uint8_t flag)
 				break;
 		}
 		++udata.u_base;
-		++written;
+		++udata.u_done;
 	}
-	return written;
+	return udata.u_done;
 }