kernel: introduce devself

Devself provides to each process access to its own structures.

So far it contains four files:

- pid
- ppid
- pipes	used to implement pipe(2)
- segments used to implement segattach, segdetach and segfree

qa/kern/getpid.c

@@ -36,13 +36,8 @@ main(void)
 		exits("FAIL");
 	}
 	rfork(RFNOMNT|RFCNAMEG);
-	if(getpid() != -1){
+	if(getpid() != pid){
-		print("FAIL: rfork(RFNOMNT|RFCNAMEG)); getpid() != -1\n");
+		print("FAIL: rfork(RFNOMNT|RFCNAMEG)); getpid() != getmainpid()\n");
-		exits("FAIL");
-	}
-	rerrstr(err, ERRMAX);
-	if(strcmp("getpid: cannot open neither #c/pid nor /dev/pid", err)){
-		print("FAIL: rfork(RFNOMNT|RFCNAMEG)); getpid() set errstr '%s'\n", err);
 		exits("FAIL");
 	}
 

qa/kern/getppid.c

@@ -38,13 +38,8 @@ main(void)
 			exits("FAIL");
 		}
 		rfork(RFNOMNT|RFCNAMEG);
-		if(getppid() != -1){
+		if(getppid() != ppid){
-			print("FAIL: rfork(RFNOMNT|RFCNAMEG)); getppid() != -1\n");
+			print("FAIL: rfork(RFNOMNT|RFCNAMEG)); getppid() != getmainpid()\n");
-			exits("FAIL");
-		}
-		rerrstr(err, ERRMAX);
-		if(strcmp("getppid: cannot open neither #c/ppid nor /dev/ppid", err)){
-			print("FAIL: rfork(RFNOMNT|RFCNAMEG)); getppid() set errstr '%s'\n", err);
 			exits("FAIL");
 		}
 		exits(nil);

sys/include/libc.h

@@ -396,6 +396,7 @@ extern	char*	mktemp(char*);
 extern	double	modf(double, double*);
 extern	void	notejmp(void*, jmp_buf, int);
 extern	void	perror(const char*);
+extern	int	pipe(int pipes[2]);
 extern	int	postnote(int, int, const char *);
 extern	double	pow10(int);
 extern	int	putenv(const char*, const char*);

sys/src/kern/amd64/build.json

@@ -36,6 +36,7 @@
 					"root",
 					"rtc",
 					"sd",
+					"self",
 					"shr",
 					"srv",
 					"ssl",

sys/src/kern/amd64/workhorse.json

@@ -32,6 +32,7 @@
 					"proc",
 					"root",
 					"sd",
+					"self",
 					"shr",
 					"srv",
 					"uart"

sys/src/kern/port/chan.c

@@ -1291,9 +1291,10 @@ namec(char *aname, int amode, int omode, int perm)
 		 * noattach is sandboxing.
 		 *
 		 * the OK exceptions are:
-		 *	|  it only gives access to pipes you create
+		 *	|  current process's pipes
-		 *	d  this process's file descriptors
+		 * 	0  current process's kernel infos
-		 *	e  this process's environment
+		 *	d  current process's file descriptors
+		 *	e  current process's environment
 		 * NOTE: Plan9 also allows
 		 *	c  time and pid, but also cons and consctl
 		 *	p  control of your own processes (and unfortunately
@@ -1303,7 +1304,7 @@ namec(char *aname, int amode, int omode, int perm)
 		 * Who actually need them can bind #c and #p somewhere
 		 * before rfork(RFNOMNT)
 		 */
-		if(up->pgrp->noattach && utfrune("|de", r)==nil)
+		if(up->pgrp->noattach && utfrune("|0de", r)==nil)
 			error(Enoattach);
 		dev = devtabget(r, 1);			//XDYNX
 		if(dev == nil)

sys/src/kern/port/devcons.c

@@ -680,8 +680,6 @@ enum{
 	Qnull,
 	Qosversion,
 	Qpgrpid,
-	Qpid,
-	Qppid,
 	Qrandom,
 	Qreboot,
 	Qswap,
@@ -713,8 +711,6 @@ static Dirtab consdir[]={
 	"null",		{Qnull},	0,		0666,
 	"osversion",	{Qosversion},	0,		0444,
 	"pgrpid",	{Qpgrpid},	NUMSIZE,	0444,
-	"pid",		{Qpid},		NUMSIZE,	0444,
-	"ppid",		{Qppid},	NUMSIZE,	0444,
 	"random",	{Qrandom},	0,		0444,
 	"reboot",	{Qreboot},	0,		0664,
 	"swap",		{Qswap},	0,		0664,
@@ -944,12 +940,6 @@ consread(Chan *c, void *buf, long n, int64_t off)
 	case Qpgrpid:
 		return readnum(offset, buf, n, up->pgrp->pgrpid, NUMSIZE);
 
-	case Qpid:
-		return readnum(offset, buf, n, up->pid, NUMSIZE);
-
-	case Qppid:
-		return readnum(offset, buf, n, up->parentpid, NUMSIZE);
-
 	case Qtime:
 		return readtime(offset, buf, n);
 

sys/src/kern/port/devdup.c

@@ -12,7 +12,7 @@ dupgen(Chan *c, char * _1, Dirtab* _2, int _3, int s, Dir *dp)
 {
 	Fgrp *fgrp = up->fgrp;
 	Chan *f;
-	static int perm[] = { 0400, 0200, 0600, 0 };
+	static int perm[] = { 0, 0400, 0200, 0600, 0 };
 	int p;
 	Qid q;
 
@@ -31,7 +31,7 @@ dupgen(Chan *c, char * _1, Dirtab* _2, int _3, int s, Dir *dp)
 		p = 0400;
 		sprint(up->genbuf, "%dctl", s/2);
 	}else{
-		p = perm[f->mode&3];
+		p = perm[f->mode&7];
 		sprint(up->genbuf, "%d", s/2);
 	}
 	mkqid(&q, s+1, 0, QTFILE);

sys/src/kern/port/devproc.c

@@ -1,3 +1,20 @@
+/*
+ * This file is part of Jehanne.
+ *
+ * Copyright (C) 2015-2016 Giacomo Tesio <giacomo@tesio.it>
+ *
+ * Jehanne is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 2 of the License.
+ *
+ * Jehanne is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Jehanne.  If not, see <http://www.gnu.org/licenses/>.
+ */
 #include	"u.h"
 #include	"../port/lib.h"
 #include	"mem.h"
@@ -51,11 +68,6 @@ enum
 	CMwaitstop,
 	CMwired,
 	CMtrace,
-
-	/* segments */
-	CMsegattach,
-	CMsegdetach,
-	CMsegfree,
 };
 
 enum{
@@ -83,7 +95,7 @@ Dirtab procdir[] =
 	"ns",		{Qns},		0,			0444,
 	"proc",		{Qproc},	0,			0400,
 	"regs",		{Qregs},	sizeof(Ureg),		0000,
-	"segment",	{Qsegment},	0,			0644,
+	"segment",	{Qsegment},	0,			0444,
 	"status",	{Qstatus},	STATSIZE,		0444,
 	"text",		{Qtext},	0,			0000,
 	"wait",		{Qwait},	0,			0400,
@@ -108,9 +120,6 @@ Cmdtab proccmd[] = {
 	CMwaitstop,		"waitstop",		1,
 	CMwired,		"wired",		2,
 	CMtrace,		"trace",		0,
-	CMsegattach,		"attach",		5,
-	CMsegdetach,		"detach",		2,
-	CMsegfree,		"free",			3,
 };
 
 /*
@@ -366,7 +375,6 @@ procopen(Chan *c, unsigned long omode)
 
 	case Qsegment:
 		if(omode != OREAD && omode != OSTAT)
-		if(omode != OWRITE || up->pid != pid)
 			error(Eperm);
 		break;
 
@@ -1092,137 +1100,6 @@ mntscan(Mntwalk *mw, Proc *p)
 	runlock(&pg->ns);
 }
 
-static uintptr_t
-segattach(Proc* p, int attr, const char* name, uintptr_t va, usize len)
-{
-	unsigned int sno, tmp;
-	ProcSegment *s;
-	uintptr_t pa, size;
-
-
-	if((va != 0 && va < UTZERO) || iskaddr(va))
-		error("virtual address below text or in kernel");
-
-	vmemchr((void *)name, 0, ~0);
-
-	for(sno = 0; sno < NSEG; sno++)
-		if(p->seg[sno] == nil && sno != ESEG)
-			break;
-
-	if(sno == NSEG)
-		error("too many segments in process");
-
-	len = ROUNDUP(va+len, PGSZ) - ROUNDDN(va, PGSZ);
-	va = ROUNDDN(va, PGSZ);
-
-	if(rawmem_find((char**)&name, &pa, &tmp, &size)){
-		s = 0;
-		wlock(&p->seglock);
-		if(pa){
-			if(!segment_physical(&s, attr&SegPermissionMask, attr&SegFlagMask, va, pa))
-				goto SegAttachEbadarg;
-		} else if(size != -1){
-			if(!segment_global(&s, attr&SegPermissionMask, va, (char*)name))
-				goto SegAttachEbadarg;
-		} else {
-			if(!segment_virtual(&s, tmp&SegmentTypesMask, attr&SegPermissionMask&~SgExecute, attr&SegFlagMask, va, va+len))
-				goto SegAttachEbadarg;
-		}
-		for(tmp = 0; tmp < NSEG; tmp++){
-			if(p->seg[tmp])
-			if((p->seg[tmp]->base > s->base && p->seg[tmp]->base < s->top)
-			|| (p->seg[tmp]->top > s->base && p->seg[tmp]->top < s->top)){
-				goto SegAttachEsoverlap;
-			}
-		}
-		up->seg[sno] = s;
-		wunlock(&p->seglock);
-		return s->base;
-	}
-	error("segment not found");
-SegAttachEbadarg:
-	wunlock(&p->seglock);
-	error(Ebadarg);
-SegAttachEsoverlap:
-	wunlock(&p->seglock);
-	segment_release(&s);
-	error(Esoverlap);
-}
-
-static uintptr_t
-segdetach(Proc* p, uintptr_t va)
-{
-	if(!proc_segment_detach(p, va))
-		error(Ebadarg);
-
-	mmuflush();
-	return 0;
-}
-
-static uintptr_t
-segfree(Proc* p, uintptr_t va, unsigned long len)
-{
-	ProcSegment *s;
-	uintptr_t from, to;
-
-	from = PTR2UINT(va);
-	to = ROUNDDN(from + len, PGSZ);
-
-	s = proc_segment(p, from);
-	if(s == nil || to < from || to > s->top)
-		error(Ebadarg);
-
-	from = ROUNDUP(from, PGSZ);
-	if(from == to)
-		return 0;
-
-	segment_free_pages(s, from, to);
-	mmuflush();
-	return 0;
-}
-
-static long
-procsegctl(Proc *p, char *va, int n)
-{
-	Cmdbuf *cb;
-	Cmdtab *ct;
-	int attr;
-	const char *class;
-	uintptr_t vareq;
-	unsigned long len;
-	long result;
-
-	cb = parsecmd(va, n);
-	if(waserror()){
-		free(cb);
-		nexterror();
-	}
-
-	ct = lookupcmd(cb, proccmd, nelem(proccmd));
-	switch(ct->index){
-	default:
-		error(Ebadctl);
-		return -1;
-	case CMsegattach:
-		attr = strtoul(cb->f[1], 0, 0);
-		vareq = strtoull(cb->f[2], 0, 0);
-		len = strtoull(cb->f[3], 0, 0);
-		class = cb->f[4];
-		result = segattach(p, attr, class, vareq, len);
-		break;
-	case CMsegdetach:
-		vareq = strtoull(cb->f[1], 0, 0);
-		result = segdetach(p, vareq);
-		break;
-	case CMsegfree:
-		vareq = strtoull(cb->f[1], 0, 0);
-		len = strtoull(cb->f[2], 0, 0);
-		result = segfree(p, vareq, len);
-		break;
-	}
-	poperror();
-	return result;
-}
 
 static long
 procwrite(Chan *c, void *va, long n, int64_t off)
@@ -1300,10 +1177,6 @@ procwrite(Chan *c, void *va, long n, int64_t off)
 		n = fpudevprocio(p, va, n, offset, 1);
 		break;
 
-	case Qsegment:
-		n = procsegctl(p, va, n);
-		break;
-
 	case Qctl:
 		procctlreq(p, va, n);
 		break;

sys/src/kern/port/devself.c

@@ -0,0 +1,387 @@
+/*
+ * This file is part of Jehanne.
+ *
+ * Copyright (C) 2016 Giacomo Tesio <giacomo@tesio.it>
+ *
+ * Jehanne is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 2 of the License.
+ *
+ * Jehanne is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Jehanne.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include	"u.h"
+#include	"../port/lib.h"
+#include	"mem.h"
+#include	"dat.h"
+#include	"fns.h"
+#include	"../port/error.h"
+
+#define QID(q)		((((uint32_t)(q).path)&0x0000001F)>>0)
+#define STATSIZE	(2*KNAMELEN+NUMSIZE+9*NUMSIZE + 1)
+
+/* devself provides to each process access to its own structures
+ * (pid, ppid, segments...).
+ */
+typedef enum SelfNodes
+{
+	Qdir,
+
+	/* Process control */
+	Qpid,
+	Qppid,
+	Qsegments,
+	Qpipes,
+} SelfNodes;
+
+typedef enum SegmentsCmd
+{
+	CMsegattach,
+	CMsegdetach,
+	CMsegfree,
+} SegmentsCmd;
+
+static
+Cmdtab proccmd[] = {
+	CMsegattach,		"attach",		5,
+	CMsegdetach,		"detach",		2,
+	CMsegfree,		"free",			3,
+};
+
+typedef union PipeSet
+{
+	long	merged;
+	int	fd[2];
+} PipeSet;
+
+static Dirtab selfdir[]={
+	".",		{Qdir, 0, QTDIR},	0,		DMDIR|0777,
+	"pid",		{Qpid},			0,		0,
+	"ppid",		{Qppid},		0,		0,
+	"segments",	{Qsegments},		0,		0644,
+	"pipes",	{Qpipes},		0,		0,
+};
+
+
+static Chan*
+selfattach(Chan *c, Chan *ac, char *spec, int flags)
+{
+	return devattach('0', spec);
+}
+
+static Walkqid*
+selfwalk(Chan *c, Chan *nc, char **name, int nname)
+{
+	return devwalk(c, nc, name, nname, selfdir, nelem(selfdir), devgen);
+}
+
+static long
+selfstat(Chan *c, uint8_t *dp, long n)
+{
+	return devstat(c, dp, n, selfdir, nelem(selfdir), devgen);
+}
+
+static Chan*
+selfopen(Chan *c, unsigned long omode)
+{
+	c->aux = nil;
+	c = devopen(c, omode, selfdir, nelem(selfdir), devgen);
+	return c;
+}
+
+static long
+selfread(Chan *c, void *va, long n, int64_t off)
+{
+	int64_t offset;
+	ProcSegment *sg;
+	int i, j;
+	char statbuf[NSEG*STATSIZE];
+
+	offset = off;
+	switch(QID(c->qid)){
+	case Qsegments:
+		rlock(&up->seglock);
+		j = 0;
+		for(i = 0; i < NSEG; i++) {
+			sg = up->seg[i];
+			if(sg == 0)
+				continue;
+			j += sprint(statbuf+j, "%-6s %c%c %p %p %4d\n",
+				segment_name(sg),
+				!(sg->type&SgWrite) ? 'R' : ' ',
+				(sg->type&SgExecute) ? 'x' : ' ',
+				' ', // sg->profile ? 'P' : ' ', // here was profiling
+				sg->base, sg->top, sg->r.ref);
+		}
+		runlock(&up->seglock);
+		if(offset >= j)
+			return 0;
+		if(offset+n > j)
+			n = j-offset;
+		if(n == 0 && offset == 0)
+			exhausted("segments");
+		memmove(va, &statbuf[offset], n);
+		return n;
+	default:
+		error(Egreg);
+	}
+}
+
+static uintptr_t
+segattach(Proc* p, int attr, const char* name, uintptr_t va, usize len)
+{
+	unsigned int sno, tmp;
+	ProcSegment *s;
+	uintptr_t pa, size;
+
+
+	if((va != 0 && va < UTZERO) || iskaddr(va))
+		error("virtual address below text or in kernel");
+
+	vmemchr((void *)name, 0, ~0);
+
+	for(sno = 0; sno < NSEG; sno++)
+		if(p->seg[sno] == nil && sno != ESEG)
+			break;
+
+	if(sno == NSEG)
+		error("too many segments in process");
+
+	len = ROUNDUP(va+len, PGSZ) - ROUNDDN(va, PGSZ);
+	va = ROUNDDN(va, PGSZ);
+
+	if(rawmem_find((char**)&name, &pa, &tmp, &size)){
+		s = 0;
+		wlock(&p->seglock);
+		if(pa){
+			if(!segment_physical(&s, attr&SegPermissionMask, attr&SegFlagMask, va, pa))
+				goto SegAttachEbadarg;
+		} else if(size != -1){
+			if(!segment_global(&s, attr&SegPermissionMask, va, (char*)name))
+				goto SegAttachEbadarg;
+		} else {
+			if(!segment_virtual(&s, tmp&SegmentTypesMask, attr&SegPermissionMask&~SgExecute, attr&SegFlagMask, va, va+len))
+				goto SegAttachEbadarg;
+		}
+		for(tmp = 0; tmp < NSEG; tmp++){
+			if(p->seg[tmp])
+			if((p->seg[tmp]->base > s->base && p->seg[tmp]->base < s->top)
+			|| (p->seg[tmp]->top > s->base && p->seg[tmp]->top < s->top)){
+				goto SegAttachEsoverlap;
+			}
+		}
+		up->seg[sno] = s;
+		wunlock(&p->seglock);
+		return s->base;
+	}
+	error("segment not found");
+SegAttachEbadarg:
+	wunlock(&p->seglock);
+	error(Ebadarg);
+SegAttachEsoverlap:
+	wunlock(&p->seglock);
+	segment_release(&s);
+	error(Esoverlap);
+}
+
+static uintptr_t
+segdetach(Proc* p, uintptr_t va)
+{
+	if(!proc_segment_detach(p, va))
+		error(Ebadarg);
+
+	mmuflush();
+	return 0;
+}
+
+static uintptr_t
+segfree(Proc* p, uintptr_t va, unsigned long len)
+{
+	ProcSegment *s;
+	uintptr_t from, to;
+
+	from = PTR2UINT(va);
+	to = ROUNDDN(from + len, PGSZ);
+
+	s = proc_segment(p, from);
+	if(s == nil || to < from || to > s->top)
+		error(Ebadarg);
+
+	from = ROUNDUP(from, PGSZ);
+	if(from == to)
+		return 0;
+
+	segment_free_pages(s, from, to);
+	mmuflush();
+	return 0;
+}
+
+static long
+procsegctl(Proc *p, char *va, int n)
+{
+	Cmdbuf *cb;
+	Cmdtab *ct;
+	int attr;
+	const char *class;
+	uintptr_t vareq;
+	unsigned long len;
+	long result;
+
+	cb = parsecmd(va, n);
+	if(waserror()){
+		free(cb);
+		nexterror();
+	}
+
+	ct = lookupcmd(cb, proccmd, nelem(proccmd));
+	switch(ct->index){
+	default:
+		error(Ebadctl);
+		return -1;
+	case CMsegattach:
+		attr = strtoul(cb->f[1], 0, 0);
+		vareq = strtoull(cb->f[2], 0, 0);
+		len = strtoull(cb->f[3], 0, 0);
+		class = cb->f[4];
+		result = segattach(p, attr, class, vareq, len);
+		break;
+	case CMsegdetach:
+		vareq = strtoull(cb->f[1], 0, 0);
+		result = segdetach(p, vareq);
+		break;
+	case CMsegfree:
+		vareq = strtoull(cb->f[1], 0, 0);
+		len = strtoull(cb->f[2], 0, 0);
+		result = segfree(p, vareq, len);
+		break;
+	}
+	poperror();
+	return result;
+}
+
+static long
+selfwrite(Chan *c, void *va, long n, int64_t off)
+{
+	switch(QID(c->qid)){
+	default:
+		error(Egreg);
+	case Qsegments:
+		n = procsegctl(up, va, n);
+		break;
+	}
+	return n;
+}
+
+static int
+newfd2(int fd[2], Chan *c[2])
+{
+	extern int findfreefd(Fgrp *f, int start);
+	extern void unlockfgrp(Fgrp *f);
+	Fgrp *f;
+
+	f = up->fgrp;
+	lock(&f->l);
+	fd[0] = findfreefd(f, 0);
+	if(fd[0] < 0){
+		unlockfgrp(f);
+		return -1;
+	}
+	fd[1] = findfreefd(f, fd[0]+1);
+	if(fd[1] < 0){
+		unlockfgrp(f);
+		return -1;
+	}
+	if(fd[1] > f->maxfd)
+		f->maxfd = fd[1];
+	f->fd[fd[0]] = c[0];
+	f->fd[fd[1]] = c[1];
+	unlockfgrp(f);
+
+	return 0;
+}
+
+static long
+newpipe(void)
+{
+	PipeSet pipe;
+	Chan *c[2];
+	static char *datastr[] = {"data", "data1"};
+
+	c[0] = namec("#|", Atodir, 0, 0);
+	c[1] = nil;
+	pipe.fd[0] = -1;
+	pipe.fd[1] = -1;
+
+	if(waserror()){
+		cclose(c[0]);
+		if(c[1])
+			cclose(c[1]);
+		nexterror();
+	}
+	c[1] = cclone(c[0]);
+	if(walk(&c[0], datastr+0, 1, 1, nil) < 0)
+		error(Egreg);
+	if(walk(&c[1], datastr+1, 1, 1, nil) < 0)
+		error(Egreg);
+	c[0] = c[0]->dev->open(c[0], ORDWR);
+	c[1] = c[1]->dev->open(c[1], ORDWR);
+	if(newfd2(pipe.fd, c) < 0)
+		error(Enofd);
+	poperror();
+
+	return pipe.merged;
+}
+
+static void
+selfremove(Chan* c)
+{
+	long pipeset;
+	switch((uint32_t)c->qid.path){
+	case Qsegments:
+		error(Eperm);
+		break;
+	case Qpid:
+		errorl("got pid", up->pid);
+		break;
+	case Qppid:
+		errorl("got parent pid", up->parentpid);
+		break;
+	case Qpipes:
+		pipeset = newpipe();
+		errorl("got new pipes", pipeset);
+		break;
+	}
+}
+
+
+static void
+selfclose(Chan *c)
+{
+}
+
+
+Dev selfdevtab = {
+	'0',
+	"self",
+
+	devreset,
+	devinit,
+	devshutdown,
+	selfattach,
+	selfwalk,
+	selfstat,
+	selfopen,
+	devcreate,
+	selfclose,
+	selfread,
+	devbread,
+	selfwrite,
+	devbwrite,
+	selfremove,
+	devwstat,
+};

sys/src/kern/port/include.json

@@ -23,6 +23,7 @@
 			"../port/chan.c",
 			"../port/debug.c",
 			"../port/dev.c",
+			"../port/dev9p.c",
 			"../port/devbridge.c",
 			"../port/devcap.c",
 			"../port/devcons.c",
@@ -30,12 +31,12 @@
 			"../port/devenv.c",
 			"../port/devfs.c",
 			"../port/devkprof.c",
-			"../port/dev9p.c",
 			"../port/devpci.c",
 			"../port/devpipe.c",
 			"../port/devproc.c",
 			"../port/devroot.c",
 			"../port/devsd.c",
+			"../port/devself.c",
 			"../port/devshr.c",
 			"../port/devsrv.c",
 			"../port/devssl.c",

sys/src/kern/port/sysfile.c

@@ -26,7 +26,7 @@
  * The sys*() routines needn't poperror() as they return directly to syscall().
  */
 
-static void
+void
 unlockfgrp(Fgrp *f)
 {
 	int ex;
@@ -74,7 +74,7 @@ growfd(Fgrp *f, int fd)	/* fd is always >= 0 */
 /*
  *  this assumes that the fgrp is locked
  */
-static int
+int
 findfreefd(Fgrp *f, int start)
 {
 	int fd;
@@ -107,32 +107,6 @@ newfd(Chan *c)
 	return fd;
 }
 
-static int
-newfd2(int fd[2], Chan *c[2])
-{
-	Fgrp *f;
-
-	f = up->fgrp;
-	lock(&f->l);
-	fd[0] = findfreefd(f, 0);
-	if(fd[0] < 0){
-		unlockfgrp(f);
-		return -1;
-	}
-	fd[1] = findfreefd(f, fd[0]+1);
-	if(fd[1] < 0){
-		unlockfgrp(f);
-		return -1;
-	}
-	if(fd[1] > f->maxfd)
-		f->maxfd = fd[1];
-	f->fd[fd[0]] = c[0];
-	f->fd[fd[1]] = c[1];
-	unlockfgrp(f);
-
-	return 0;
-}
-
 Chan*
 fdtochan(int fd, unsigned long mode, int chkmnt, int iref)
 {
@@ -205,44 +179,6 @@ sysfd2path(int fd, char* buf, int nbuf)
 	return 0;
 }
 
-int
-syspipe(int* a)
-{
-	int fd[2];
-	Chan *c[2];
-	static char *datastr[] = {"data", "data1"};
-
-	a = validaddr(a, sizeof(fd), 1);
-	evenaddr(PTR2UINT(a));
-
-	c[0] = namec("#|", Atodir, 0, 0);
-	c[1] = nil;
-	fd[0] = -1;
-	fd[1] = -1;
-
-	if(waserror()){
-		cclose(c[0]);
-		if(c[1])
-			cclose(c[1]);
-		nexterror();
-	}
-	c[1] = cclone(c[0]);
-	if(walk(&c[0], datastr+0, 1, 1, nil) < 0)
-		error(Egreg);
-	if(walk(&c[1], datastr+1, 1, 1, nil) < 0)
-		error(Egreg);
-	c[0] = c[0]->dev->open(c[0], ORDWR);
-	c[1] = c[1]->dev->open(c[1], ORDWR);
-	if(newfd2(fd, c) < 0)
-		error(Enofd);
-	poperror();
-
-	a[0] = fd[0];
-	a[1] = fd[1];
-
-	return 0;
-}
-
 int
 sysdup(int ofd, int nfd)
 {

sys/src/lib/c/9sys/getpid.c

@@ -22,20 +22,7 @@
 int
 getpid(void)
 {
-	char buf[20];
 	int pid;
-
+	pid = (int)remove("#0/pid");
-	pid = open("#c/pid", OREAD);
+	return pid;
-	if(pid < 0){
-		// probably rfork(RFNOMNT)
-		pid = open("/dev/pid", OREAD);
-		if(pid < 0){
-			werrstr("getpid: cannot open neither #c/pid nor /dev/pid");
-			return -1;	// probably rfork(RFNOMNT|RFCNAMEG)
-		}
-	}
-	memset(buf, 0, sizeof(buf));
-	assert(read(pid, buf, sizeof(buf)) > 0);
-	close(pid);
-	return atol(buf);
 }

sys/src/lib/c/9sys/getppid.c

@@ -22,20 +22,7 @@
 int
 getppid(void)
 {
-	char buf[20];
+	int pid;
-	int ppid;
+	pid = (int)remove("#0/ppid");
-
+	return pid;
-	ppid = open("#c/ppid", OREAD);
-	if(ppid < 0){
-		// probably rfork(RFNOMNT)
-		ppid = open("/dev/ppid", OREAD);
-		if(ppid < 0){
-			werrstr("getppid: cannot open neither #c/ppid nor /dev/ppid");
-			return -1;	// probably rfork(RFNOMNT|RFCNAMEG)
-		}
-	}
-	memset(buf, 0, sizeof(buf));
-	assert(read(ppid, buf, sizeof(buf)) > 0);
-	close(ppid);
-	return atol(buf);
 }

sys/src/lib/c/9sys/pipe.c

@@ -0,0 +1,37 @@
+/*
+ * This file is part of Jehanne.
+ *
+ * Copyright (C) 2015-2017 Giacomo Tesio <giacomo@tesio.it>
+ *
+ * Jehanne is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 2 of the License.
+ *
+ * Jehanne is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Jehanne.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <u.h>
+#include <libc.h>
+
+typedef union PipeSet
+{
+	long	merged;
+	int	fd[2];
+} PipeSet;
+
+int
+pipe(int pipes[2])
+{
+	PipeSet pset;
+	pset.merged = remove("#0/pipes");
+	if(pset.merged == -1)
+		return -1;
+	pipes[0] = pset.fd[0];
+	pipes[1] = pset.fd[1];
+	return 0;
+}

sys/src/lib/c/9sys/segattach.c

@@ -18,21 +18,6 @@
 #include <u.h>
 #include <libc.h>
 
-static int
-opensegment(int pid)
-{
-	char file[128];
-	int32_t f;
-
-	sprint(file, "#p/%d/segment", pid);
-	f = open(file, OWRITE);
-	if(f < 0){
-		sprint(file, "/proc/%d/segment", pid);
-		f = open(file, OWRITE);
-	}
-	return f;
-}
-
 void*
 segattach(int attr, const char *class, void *va, unsigned long len)
 {
@@ -40,8 +25,7 @@ segattach(int attr, const char *class, void *va, unsigned long len)
 	long tmp;
 	char msg[256];
 
-	tmp = getpid();
+	fd = open("#0/segments", OWRITE);
-	fd = opensegment(tmp);
 	if(fd < 0)
 		return (void*)-1;
 
@@ -57,8 +41,7 @@ segdetach(void *addr)
 	int fd, tmp;
 	char msg[256];
 
-	tmp = getpid();
+	fd = open("#0/segments", OWRITE);
-	fd = opensegment(tmp);
 	if(fd < 0)
 		return -1;
 
@@ -74,8 +57,7 @@ segfree(void *addr, unsigned long len)
 	int fd, tmp;
 	char msg[256];
 
-	tmp = getpid();
+	fd = open("#0/segments", OWRITE);
-	fd = opensegment(tmp);
 	if(fd < 0)
 		return -1;
 

sys/src/lib/c/build.json

@@ -58,6 +58,7 @@
 			"9sys/getwd.c",
 			"9sys/iounit.c",
 			"9sys/nulldir.c",
+			"9sys/pipe.c",
 			"9sys/postnote.c",
 			"9sys/privalloc.c",
 			"9sys/pushssl.c",

sys/src/sysconf.json

@@ -251,16 +251,6 @@
 				"long"
 			]
 		},
-		{
-			"Args": [
-				"int*"
-			],
-			"Id": 21,
-			"Name": "pipe",
-			"Ret": [
-				"int"
-			]
-		},
 		{
 			"Args": [
 				"int",
@@ -268,7 +258,7 @@
 				"int",
 				"long"
 			],
-			"Id": 22,
+			"Id": 21,
 			"Name": "pread",
 			"Ret": [
 				"long"
@@ -281,7 +271,7 @@
 				"int",
 				"long"
 			],
-			"Id": 23,
+			"Id": 22,
 			"Name": "pwrite",
 			"Ret": [
 				"long"
@@ -291,7 +281,7 @@
 			"Args": [
 				"const char*"
 			],
-			"Id": 24,
+			"Id": 23,
 			"Name": "remove",
 			"Ret": [
 				"long"
@@ -302,7 +292,7 @@
 				"const void*",
 				"void*"
 			],
-			"Id": 25,
+			"Id": 24,
 			"Name": "rendezvous",
 			"Ret": [
 				"void*"
@@ -312,7 +302,7 @@
 			"Args": [
 				"uint32_t"
 			],
-			"Id": 26,
+			"Id": 25,
 			"Name": "rfork",
 			"Ret": [
 				"int"
@@ -324,7 +314,7 @@
 				"long",
 				"int"
 			],
-			"Id": 27,
+			"Id": 26,
 			"Name": "seek",
 			"Ret": [
 				"long"
@@ -335,7 +325,7 @@
 				"int*",
 				"int"
 			],
-			"Id": 28,
+			"Id": 27,
 			"Name": "semacquire",
 			"Ret": [
 				"int"
@@ -346,7 +336,7 @@
 				"int*",
 				"int"
 			],
-			"Id": 29,
+			"Id": 28,
 			"Name": "semrelease",
 			"Ret": [
 				"int"
@@ -357,7 +347,7 @@
 				"int*",
 				"uint64_t"
 			],
-			"Id": 30,
+			"Id": 29,
 			"Name": "tsemacquire",
 			"Ret": [
 				"int"
@@ -368,7 +358,7 @@
 				"const char*",
 				"const char*"
 			],
-			"Id": 31,
+			"Id": 30,
 			"Name": "unmount",
 			"Ret": [
 				"int"
@@ -378,7 +368,7 @@
 			"Args": [
 				"unsigned long"
 			],
-			"Id": 32,
+			"Id": 31,
 			"Name": "alarm",
 			"Ret": [
 				"long"