# HG changeset patch
# User Erik Quanstrom <quanstro@quanstro.net>
# Date 1331047072 -3600
# Node ID 33a08947f013d09d8d75bcf765857e8b3b4909d4
# Parent  e5d11ac11abaa21562e0edd3cfe77e1fc351ffc5
devproc: fix check for too many procs, and other nits

1.  derive how many procs we can have from the qid
masks, rather than leaving it to chance.

2.  fix channel leak on opening "text".

3.  do correct arithmetic in calculating total segment
size.  the display is still wrong for procs bigger than
4gb<<10 (4tb), since the width of the text field wasn't
change for backwards compatability reasons.

R=nixiedev, nemo.mbox, charles.forsyth, nemo
CC=nix-dev
http://codereview.appspot.com/5703046

Committer: Francisco J Ballesteros <nemo.mbox@gmail.com>

diff -r e5d11ac11aba -r 33a08947f013 sys/src/nix/port/devproc.c
--- a/sys/src/nix/port/devproc.c	Tue Mar 06 16:17:03 2012 +0100
+++ b/sys/src/nix/port/devproc.c	Tue Mar 06 16:17:52 2012 +0100
@@ -88,7 +88,7 @@
 	"ctl",		{Qctl},		0,			0000,
 	"fd",		{Qfd},		0,			0444,
 	"fpregs",	{Qfpregs},	0,			0000,
-	"kregs",	{Qkregs},	sizeof(Ureg),		0400,
+	"kregs",	{Qkregs},	sizeof(Ureg),		0600,
 	"mem",		{Qmem},		0,			0000,
 	"note",		{Qnote},	0,			0000,
 	"noteid",	{Qnoteid},	0,			0664,
@@ -147,10 +147,13 @@
  *	32 bits of pid, for consistency checking
  * If notepg, c->pgrpid.path is pgrp slot, .vers is noteid.
  */
-#define QSHIFT	5	/* location in qid of proc slot # */
+#define	QSHIFT	5	/* location in qid of proc slot # */
+#define	SLOTBITS 23	/* number of bits in the slot */
+#define	QIDMASK	((1<<QSHIFT)-1)
+#define	SLOTMASK	((1<<SLOTBITS)-1 << QSHIFT)
 
-#define QID(q)		((((ulong)(q).path)&0x0000001F)>>0)
-#define SLOT(q)		(((((ulong)(q).path)&0x07FFFFFE0)>>QSHIFT)-1)
+#define QID(q)		((((ulong)(q).path)&QIDMASK)>>0)
+#define SLOT(q)		(((((ulong)(q).path)&SLOTMASK)>>QSHIFT)-1)
 #define PID(q)		((q).vers)
 #define NOTEID(q)	((q).vers)
 
@@ -230,7 +233,7 @@
 
 		if((p = psincref(s)) == nil || (pid = p->pid) == 0)
 			return 0;
-		sprint(up->genbuf, "%d", pid);
+		snprint(up->genbuf, sizeof up->genbuf, "%ud", pid);
 		/*
 		 * String comparison is done in devwalk so
 		 * name must match its formatted pid.
@@ -335,7 +338,7 @@
 static void
 procinit(void)
 {
-	if(conf.nproc >= (1<<(16-QSHIFT))-1)
+	if(conf.nproc >= (SLOTMASK>>QSHIFT) - 1)
 		print("warning: too many procs for devproc\n");
 	addclock0link((void (*)(void))profclock, 113);	/* Relative prime to HZ */
 }
@@ -400,9 +403,14 @@
 		topens++;
 		if (tevents == nil){
 			tevents = (Traceevent*)malloc(sizeof(Traceevent) * Nevents);
+			if(tevents == nil)
+				error(Enomem);
 			tpids = malloc(Ntracedpids * 20);
-			if(tevents == nil || tpids == nil)
+			if(tpids == nil){
+				free(tpids);
+				tpids = nil;
 				error(Enomem);
+			}
 			tpidsc = tpids;
 			tpidse = tpids + Ntracedpids * 20;
 			*tpidsc = 0;
@@ -448,6 +456,7 @@
 		poperror();
 		qunlock(&p->debug);
 		psdecref(p);
+		cclose(c);
 		return tc;
 
 	case Qproc:
@@ -752,7 +761,7 @@
 	Segment *sg, *s;
 	int i, j, navail, pid, rsize;
 	char flag[10], *sps, *srv, statbuf[NSEG*64];
-	uintptr offset;
+	uintptr offset, u;
 	int tesz;
 
 	if(c->qid.type & QTDIR)
@@ -974,13 +983,13 @@
 			readnum(0, statbuf+j+NUMSIZE*i, NUMSIZE, l, NUMSIZE);
 		}
 		/* ignore stack, which is mostly non-existent */
-		l = 0;
+		u = 0;
 		for(i=1; i<NSEG; i++){
 			s = p->seg[i];
 			if(s)
-				l += s->top - s->base;
+				u += s->top - s->base;
 		}
-		readnum(0, statbuf+j+NUMSIZE*6, NUMSIZE, l>>10, NUMSIZE);
+		readnum(0, statbuf+j+NUMSIZE*6, NUMSIZE, u>>10u, NUMSIZE);	/* wrong size */
 		readnum(0, statbuf+j+NUMSIZE*7, NUMSIZE, p->basepri, NUMSIZE);
 		readnum(0, statbuf+j+NUMSIZE*8, NUMSIZE, p->priority, NUMSIZE);
 
@@ -1329,8 +1338,10 @@
 		error(Eprocdied);
 	}
 
-	if(p->pid != PID(c->qid))
+	if(p->pid != PID(c->qid)){
+		cclose(tc);
 		error(Eprocdied);
+	}
 
 	poperror();
 	unlock(i);
@@ -1548,10 +1559,10 @@
 	case CMtrace:
 		switch(cb->nf){
 		case 1:
-			p->trace = (p->trace?0:1);
+			p->trace ^= 1;
 			break;
 		case 2:
-			p->trace = (atoi(cb->f[1])?1:0);
+			p->trace = (atoi(cb->f[1]) != 0);
 			break;
 		default:
 			error("args");
@@ -1564,7 +1575,7 @@
 		if(e=parsetime(&time, cb->f[1]))	/* time in ns */
 			error(e);
 		edfstop(p);
-		p->edf->T = time/1000;			/* Edf times are µs */
+		p->edf->T = time/1000;			/* Edf times are in µs */
 		break;
 	case CMdeadline:
 		if(p->edf == nil)