enforce channel direction

R=ken
OCL=29209
CL=29216

diff --git a/src/cmd/gc/builtin.c.boot b/src/cmd/gc/builtin.c.boot
index 38c8b4cb5e34fb021c2b75def1925e5a00c1a468..aa51b97b53560af041abbc7b025cf32be497d7ef 100644 (file)
--- a/src/cmd/gc/builtin.c.boot
+++ b/src/cmd/gc/builtin.c.boot
@@ -48,16 +48,16 @@ char *sysimport =
        "func sys.mapiter1 (hiter *any) (key any)\n"
        "func sys.mapiter2 (hiter *any) (key any, val any)\n"
        "func sys.newchan (elemsize int, elemalg int, hint int) (hchan chan any)\n"
-       "func sys.chanrecv1 (hchan chan any) (elem any)\n"
-       "func sys.chanrecv2 (hchan chan any) (elem any, pres bool)\n"
-       "func sys.chanrecv3 (hchan chan any, elem *any) (pres bool)\n"
-       "func sys.chansend1 (hchan chan any, elem any)\n"
-       "func sys.chansend2 (hchan chan any, elem any) (pres bool)\n"
-       "func sys.closechan (hchan chan any)\n"
-       "func sys.closedchan (hchan chan any) (? bool)\n"
+       "func sys.chanrecv1 (hchan <-chan any) (elem any)\n"
+       "func sys.chanrecv2 (hchan <-chan any) (elem any, pres bool)\n"
+       "func sys.chanrecv3 (hchan <-chan any, elem *any) (pres bool)\n"
+       "func sys.chansend1 (hchan chan<- any, elem any)\n"
+       "func sys.chansend2 (hchan chan<- any, elem any) (pres bool)\n"
+       "func sys.closechan (hchan any)\n"
+       "func sys.closedchan (hchan any) (? bool)\n"
        "func sys.newselect (size int) (sel *uint8)\n"
-       "func sys.selectsend (sel *uint8, hchan chan any, elem any) (selected bool)\n"
-       "func sys.selectrecv (sel *uint8, hchan chan any, elem *any) (selected bool)\n"
+       "func sys.selectsend (sel *uint8, hchan chan<- any, elem any) (selected bool)\n"
+       "func sys.selectrecv (sel *uint8, hchan <-chan any, elem *any) (selected bool)\n"
        "func sys.selectdefault (sel *uint8) (selected bool)\n"
        "func sys.selectgo (sel *uint8)\n"
        "func sys.newarray (nel int, cap int, width int) (ary []any)\n"

diff --git a/src/cmd/gc/go.h b/src/cmd/gc/go.h
index 4d4ff3ef30d39fa2ab7bb71e0d99bcffbb160234..71aa57190bfe5340fe301d4c648ab5637483b734 100644 (file)
--- a/src/cmd/gc/go.h
+++ b/src/cmd/gc/go.h
@@ -390,9 +390,9 @@ enum
 {
        /* types of channel */
        Cxxx,
-       Cboth,
-       Crecv,
-       Csend,
+       Crecv = 1<<0,
+       Csend = 1<<1,
+       Cboth = Crecv | Csend,
 };
 
 enum

diff --git a/src/cmd/gc/subr.c b/src/cmd/gc/subr.c
index 38226a25c5d5a19daa5800a10d0fd8eb1a4b380b..3afaa5ba29e7f77a96fb2e771387ebcd61adbe8d 100644 (file)
--- a/src/cmd/gc/subr.c
+++ b/src/cmd/gc/subr.c
@@ -1067,6 +1067,8 @@ Tpretty(Fmt *fp, Type *t)
                case Crecv:
                        return fmtprint(fp, "<-chan %T", t->type);
                case Csend:
+                       if(t->type != T && t->type->etype == TCHAN)
+                               return fmtprint(fp, "chan<- (%T)", t->type);
                        return fmtprint(fp, "chan<- %T", t->type);
                }
                return fmtprint(fp, "chan %T", t->type);
@@ -1704,6 +1706,11 @@ eqtype1(Type *t1, Type *t2, int d, int names)
                if(t1->bound == t2->bound)
                        break;
                return 0;
+
+       case TCHAN:
+               if(t1->chan == t2->chan)
+                       break;
+               return 0;
        }
        return eqtype1(t1->type, t2->type, d+1, names);
 }

diff --git a/src/cmd/gc/sys.go b/src/cmd/gc/sys.go
index b5a6ddc2bb2775222fa09a13e3451013b6c83425..c3c715b7eaa0beb2fc64559e2c5da9de54780773 100644 (file)
--- a/src/cmd/gc/sys.go
+++ b/src/cmd/gc/sys.go
@@ -62,17 +62,17 @@ func        mapiter1(hiter *any) (key any);
 func   mapiter2(hiter *any) (key any, val any);
 
 func   newchan(elemsize int, elemalg int, hint int) (hchan chan any);
-func   chanrecv1(hchan chan any) (elem any);
-func   chanrecv2(hchan chan any) (elem any, pres bool);
-func   chanrecv3(hchan chan any, elem *any) (pres bool);
-func   chansend1(hchan chan any, elem any);
-func   chansend2(hchan chan any, elem any) (pres bool);
-func   closechan(hchan chan any);
-func   closedchan(hchan chan any) bool;
+func   chanrecv1(hchan <-chan any) (elem any);
+func   chanrecv2(hchan <-chan any) (elem any, pres bool);
+func   chanrecv3(hchan <-chan any, elem *any) (pres bool);
+func   chansend1(hchan chan<- any, elem any);
+func   chansend2(hchan chan<- any, elem any) (pres bool);
+func   closechan(hchan any);
+func   closedchan(hchan any) bool;
 
 func   newselect(size int) (sel *byte);
-func   selectsend(sel *byte, hchan chan any, elem any) (selected bool);
-func   selectrecv(sel *byte, hchan chan any, elem *any) (selected bool);
+func   selectsend(sel *byte, hchan chan<- any, elem any) (selected bool);
+func   selectrecv(sel *byte, hchan <-chan any, elem *any) (selected bool);
 func   selectdefault(sel *byte) (selected bool);
 func   selectgo(sel *byte);
 

diff --git a/src/cmd/gc/walk.c b/src/cmd/gc/walk.c
index e20f0c75ce5cc9b0834b336bb22d97b5fb657139..a6303a82fc475299ea581b1159be812dfee30074 100644 (file)
--- a/src/cmd/gc/walk.c
+++ b/src/cmd/gc/walk.c
@@ -1335,6 +1335,11 @@ selcase(Node *n, Node *var)
        if(t == T)
                return N;
 
+       if(!(t->chan & Csend)) {
+               yyerror("cannot send on %T", t);
+               return N;
+       }
+
        convlit(c->right, t->type);
        if(!ascompat(t->type, c->right->type)) {
                badtype(c->op, t->type, c->right->type);
@@ -1365,6 +1370,11 @@ recv:
        if(t == T)
                return N;
 
+       if(!(t->chan & Crecv)) {
+               yyerror("cannot receive from %T", t);
+               return N;
+       }
+
        // selectrecv(sel *byte, hchan *chan any, elem *any) (selected bool);
        on = syslook("selectrecv", 1);
        argtype(on, t->type);
@@ -1389,6 +1399,11 @@ recv2:
        if(t == T)
                return N;
 
+       if(!(t->chan & Crecv)) {
+               yyerror("cannot receive from %T", t);
+               return N;
+       }
+
        walktype(c->left, Elv); // elem
        convlit(c->left, t->type);
        if(!ascompat(t->type, c->left->type)) {
@@ -2103,6 +2118,14 @@ ascompat(Type *dst, Type *src)
        if(dst == T || src == T)
                return 0;
 
+       if(dst->etype == TCHAN && src->etype == TCHAN) {
+               if(!eqtype(dst->type, src->type))
+                       return 0;
+               if(dst->chan & ~src->chan)
+                       return 0;
+               return 1;
+       }
+
        if(isslice(dst)
        && isptr[src->etype]
        && isfixedarray(src->type)
@@ -2634,7 +2657,7 @@ chanop(Node *n, int top)
                r = a;
 
                on = syslook("closechan", 1);
-               argtype(on, t->type);   // any-1
+               argtype(on, t); // any-1
 
                r = nod(OCALL, on, r);
                walktype(r, top);
@@ -2651,7 +2674,7 @@ chanop(Node *n, int top)
                r = a;
 
                on = syslook("closedchan", 1);
-               argtype(on, t->type);   // any-1
+               argtype(on, t); // any-1
 
                r = nod(OCALL, on, r);
                walktype(r, top);
@@ -2704,6 +2727,11 @@ chanop(Node *n, int top)
                if(t == T)
                        break;
 
+               if(!(t->chan & Crecv)) {
+                       yyerror("cannot receive from %T", t);
+                       break;
+               }
+
                a = n->right->left;                     // chan
                r = a;
 
@@ -2727,6 +2755,11 @@ chanop(Node *n, int top)
                if(t == T)
                        break;
 
+               if(!(t->chan & Crecv)) {
+                       yyerror("cannot receive from %T", t);
+                       break;
+               }
+
                a = n->left;                    // chan
                r = a;
 
@@ -2769,14 +2802,15 @@ chanop(Node *n, int top)
                t = fixchan(n->left->type);
                if(t == T)
                        break;
+               if(!(t->chan & Csend)) {
+                       yyerror("cannot send to %T", t);
+                       break;
+               }
+
                if(top != Etop)
                        goto send2;
 
                // chansend1(hchan *chan any, elem any);
-               t = fixchan(n->left->type);
-               if(t == T)
-                       break;
-
                a = n->right;                   // e
                r = a;
                a = n->left;                    // chan
@@ -2791,10 +2825,6 @@ chanop(Node *n, int top)
 
        send2:
                // chansend2(hchan *chan any, val any) (pres bool);
-               t = fixchan(n->left->type);
-               if(t == T)
-                       break;
-
                a = n->right;                   // e
                r = a;
                a = n->left;                    // chan
@@ -4144,7 +4174,6 @@ maplit(Node *n, Node *var)
        if(r != N && r->op == OEMPTY)
                r = N;
 
-loop:
        while(r != N) {
                if(r == N)
                        break;