admin/LithosAnanake
1
1
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

feat(v4.0.0): a node finds the way -- routes, passing on, SEND; one fault stands

Browse Source 
MESH.md step 4. Each node has a table of destinations and the port toward
each, and a port for everything else (ROUTE, DEFAULT-ROUTE, NO-ROUTES). A
message not for this node is passed on whole; one with nowhere to go is
dropped and counted. What text prints and how it ended go back to the node
it came from by the same table. SEND sends text to another node.

test_host_mesh.c: three StarForth nodes in a row behind a console, 28
checks at both widths and under ASan+UBSan. hosted-check on three ISAs.
Bare metal: logs/20261006-115225 (amd64), -115501 (aarch64), -115849
(riscv64).

NOT DONE. Two neighbours that write to each other at once wait for ever:
a write blocks until the neighbour reads, and a node that is writing is
not reading. The last check in test_host_mesh.c shows it (KNOWN FAULT).
MESH.md section 7a sets out the ways out; none is chosen.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
This commit is contained in:
rajames
2026-10-06 12:01:32 -04:00
co-authored by Claude Opus 5.5
parent a041b401ea
commit 630d03fa4e
11 changed files with 820 additions and 17 deletions
Download Patch File Download Diff File Expand all files Collapse all files
v4/README.md
+9
View File
@@ -112,6 +112,15 @@ their ports are wired, both of which change while they run. The products
below are still one node each; they become the five nodes at `MESH.md`
steps 8 and 9.
**Finding the way** (`MESH.md` step 4) is built: a node has a table of
which port leads toward which node (`ROUTE`, `DEFAULT-ROUTE`, `NO-ROUTES`),
passes on a message that is not for it, and `SEND`s text to another node;
`v4/tests/test_host_mesh.c` runs three StarForth nodes in a row. **It has
a fault that stands:** two neighbours that write to each other at the same
moment wait for ever, because a write blocks until the neighbour reads and
a node that is writing is not reading. The test shows it, named KNOWN
FAULT. The ways out are in `MESH.md` section 7a and none is chosen yet.
**This is still the lone node.** On bare metal `kernel_main.c` starts it
before the fleet tables, beside the kernel's own system and not in the VM's
place. `ENGINE.md` sets out the steps from here; step 1 is done and step 2 is
v4/capsule/core.v4
+28 -11
View File
@@ -6,7 +6,8 @@
\
\ Constants the loader supplies: N-1 (cell bits - 1), NODE-ERROR, CONSOLE-TX,
\ CONSOLE-RX, CONSOLE-STATUS, BASE, (EMIT-HOOK), (MSG), (REPLY), (ME), (OUT),
\ (OUT^).
\ (OUT^), (CONSOLE), (ROUTES), (ROUTE#), (ROUTE-DEFAULT), (PRINT-TO),
\ (PRINT-PORT).
\
\ ERRORS (D-18). A word that finds an error takes its arguments off the stack
\ and stores a code in NODE-ERROR. On a node with a prompt that store is a
@@ -94,8 +95,9 @@ header CMOVE
\ ---- section 5.10: the console -------------------------------------------
\ ---- what a node prints (docs/v4.0.0/MESH.md section 6) ------------------------
\ A node has no console of its own. It does what a message asks, and what
\ it prints while doing it goes back, as a message, to whoever sent that one,
\ on the port it came on. A message is seven words and then its text, four
\ it prints while doing it is sent as a message: to the node in (CONSOLE), or
\ if that is 0 to whoever sent the text; by the port that leads there, or if
\ this node knows of none, by the port the text came on. A message is seven words and then its text, four
\ characters to a word:
\ to, from, type, heat and TTL, ACL tag, sequence, length in characters
\ The types: 1 text to be interpreted 2 what a node printed 3 how the
@@ -112,20 +114,35 @@ header CMOVE
\ the character and A on the return stack while it works. Sending needs
\ two.
\ ( type -- ) the first six words of a message to the sender of the one
\ being served; its length, and its text, are the caller's to send. Each
\ write waits for the neighbour to take it. B is left at the port.
\ FINDING THE WAY (MESH.md section 7). A node knows its ports and nothing of
\ the shape they are wired in. Whoever wires it tells it, for a node, which
\ port leads toward that node: the table (ROUTES), (ROUTE#) entries of a
\ node's number and a port's address; and (ROUTE-DEFAULT), the port for any
\ node that is not in the table, or 0.
\ ( node -- port | 0 ) the address of the port that leads toward the node
: (PORT-FOR)
(ROUTE#) a! @ if NONE -1 + (ROUTES) a!
FOR dup @+ xor if HIT drop @+ drop NEXT
0
NONE: drop drop (ROUTE-DEFAULT) a! @ ;
HIT: drop drop @+ pop drop ;
\ ( type -- ) words 1 to 5 of a message this node sends: from, type, and
\ the three that are carried and not used yet. Its caller has put B at the
\ port and sent word 0, whom it is to, and sends the length and the text.
\ Each write waits for the neighbour to take it.
: (HDR)
(REPLY) a! @ b!
(MSG)+1 a! @ !b \ to
(ME) a! @ !b \ from
!b \ type
0 !b 0 !b 0 !b ; \ heat and TTL, ACL tag, sequence: carried, not used yet
0 !b 0 !b 0 !b ; \ heat and TTL, ACL tag, sequence
\ ( -- ) send what has been printed: its length, then its characters, four
\ to a word, the first lowest
\ ( -- ) send what has been printed, to where (PRINT-TO) says, by the port
\ (PRINT-PORT): its length, then its characters, four to a word, the first
\ lowest. quit.v4 sets those two when text for this node arrives.
: (FLUSH-OUT)
(OUT^) a! @ (OUT) xor if NONE drop
(PRINT-PORT) a! @ b! (PRINT-TO) a! @ !b
2 (HDR)
(OUT^) a! @ (OUT) - dup !b
3 + 2/ 2/ -1 + (OUT) a!
v4/capsule/quit.v4
+68 -5
View File
@@ -65,6 +65,7 @@ macro R-CLEAR RSTACK-DEPTH b! a !b endmacro
: (FINISH) ( s -- )
(LINE-STATUS) b! dup !b
(FLUSH-OUT)
(DONE-PORT) a! @ b! (MSG)+1 a! @ !b \ to whoever sent the text
3 (HDR) 4 !b !b \ a message of type 3, four characters long: how it ended
jump (IDLE)
@@ -84,8 +85,8 @@ macro R-CLEAR RSTACK-DEPTH b! a !b endmacro
\ which holds 1024 characters, the most a message carries; a longer one is
\ read to its end, so that what follows it is not taken for a message, and
\ is error 12. A message of type 1 for this node is text to interpret: it
\ is done as a line was, and (FINISH) reports how it ended. Any other is
\ let go: passing a message on is MESH.md step 4.
\ is done as a line was, and (FINISH) reports how it ended. A message for
\ another node is passed on, (PASS-ON).
: (IDLE)
(PORT)+8 b! @b (MSG) a! !+ \ to, from any port
(PORT)+9 b! @b (PORT) + dup b! \ B: the port it came on
@@ -103,10 +104,32 @@ macro R-CLEAR RSTACK-DEPTH b! a !b endmacro
READ:
0 (MSG)+6 a! @ TIB + C! \ a zero after the text
(MSG)+6 a! @ SPAN a! !
(MSG) a! @ (ME) a! @ xor if MINE drop jump (IDLE)
(MSG) a! @ (ME) a! @ xor if MINE drop jump (PASS-ON)
MINE: drop
(MSG)+2 a! @ -1 + if TEXT drop jump (IDLE)
TEXT: drop jump (LINE)
(MSG)+2 a! @ -1 + if TEXT drop jump (IDLE) \ for this node and not text: let go
TEXT: drop
(MSG)+1 a! @ (PORT-FOR) if D0 jump D1 \ the way back to whoever sent it:
D0: drop (REPLY) a! @ \ the port it came on, if no other is known
D1: (DONE-PORT) a! !
(CONSOLE) a! @ if P0 jump P1 \ where what it prints goes: the console,
P0: drop (MSG)+1 a! @ \ or whoever sent it
P1: dup (PRINT-TO) a! !
(PORT-FOR) if Q0 jump Q1
Q0: drop (REPLY) a! @
Q1: (PRINT-PORT) a! !
jump (LINE)
\ ( -- ) A MESSAGE FOR ANOTHER NODE is passed on (MESH.md section 7): all
\ of it, as it came, to the port that leads toward that node. With no way
\ known it is let go, and (LOST) counts it.
: (PASS-ON)
(MSG) a! @ (PORT-FOR) if NOWAY
b! (MSG) a! 6 FOR @+ !b UNEXT \ its seven words
(MSG)+6 a! @ 3 + 2/ 2/ if SENT
-1 + TIB 2/ 2/ a! FOR @+ !b UNEXT \ and its text
jump (IDLE)
SENT: drop jump (IDLE)
NOWAY: drop (LOST) a! @ 1 + ! jump (IDLE)
\ ( -- ) THE TEXT, INTERPRETED. It is in TIB with a zero after it and its
\ length in SPAN, and the return stack is empty. It is interpreted with one
@@ -121,6 +144,43 @@ macro R-CLEAR RSTACK-DEPTH b! a !b endmacro
drop 2 jump (DONE)
GOOD: drop 1 jump (DONE)
\ ---- the node among others (MESH.md sections 6 and 7) ---------------------------
\ Not FORTH-79 and not in v3: v3's VMs are sent to through the kernel.
\ ( node port -- ) the port, by its number, leads toward that node
header ROUTE
: ROUTE
(ROUTE#) a! @ -16 + if FULL drop
(PORT) + (ROUTE#) a! @ 2* (ROUTES) + a!
push !+ pop !+
(ROUTE#) a! @ 1 + ! ;
FULL: drop drop drop NODE-ERROR b! 12 !b ;
\ ( port -- ) the port, by its number, leads toward every node not told of
header DEFAULT-ROUTE
: DEFAULT-ROUTE (PORT) + (ROUTE-DEFAULT) a! ! ;
\ ( -- ) forget every way: for when the wiring has changed
header NO-ROUTES
: NO-ROUTES 0 (ROUTE#) a! ! 0 (ROUTE-DEFAULT) a! ! ;
\ ( baddr u node -- ) send the node u characters of text to interpret. It
\ is on its way when SEND returns; what it prints there goes to that node's
\ console. With no way to the node it is error 12. The write waits for the
\ neighbour to read: a neighbour that is itself waiting to write to this
\ node will wait for ever, and so will this one.
header SEND
: SEND
dup (PORT-FOR) if NOWAY
b! !b \ to
1 (HDR)
dup !b \ length
3 + 2/ 2/ if NONE -1 +
FOR dup C@ over 1 + C@ 8* + over 2 + C@ 8* 8* + over 3 + C@ 8* 8* 8* + !b 4 + NEXT
drop ;
NONE: drop drop ;
NOWAY: drop drop drop drop NODE-ERROR b! 12 !b ;
\ FORTH-79: clear the return stack, set execution mode, return control to
\ the terminal; no message is given. The data stack is left as it is.
\ NODE-ERROR, by name: how a definition written in FORTH raises an error.
@@ -129,6 +189,9 @@ macro R-CLEAR RSTACK-DEPTH b! a !b endmacro
\ its own) and the line ends with ERROR. The codes are listed in core.v4.
header NODE-ERROR inline : NODE-ERROR' NODE-ERROR ;
header (CATCH) inline : (CATCH)' (CATCH) ;
header (ME) inline : (ME)' (ME) ;
header (CONSOLE) inline : (CONSOLE)' (CONSOLE) ;
header (LOST) inline : (LOST)' (LOST) ;
header (WORD-DEFINED) inline : (WORD-DEFINED)' (WORD-DEFINED) ;
header (WORD-FORGOTTEN) inline : (WORD-FORGOTTEN)' (WORD-FORGOTTEN) ;
header (EMIT-HOOK) inline : (EMIT-HOOK)' (EMIT-HOOK) ;
v4/tests/host_map.h
+17
View File
@@ -69,6 +69,15 @@
#define CATCH (BUF0_W - 8) /* non-zero: a line's error is recorded here, -1, and the line ends " ok" */
#define LINE_STATUS (BUF0_W - 9) /* how the last line ended: 0 QUIT, 1 completed, 2 an error */
#define PORT (BUF0_W - 32) /* the node's ports (node.h): V4_PORTS of them, then "any port" and "which port". Port 0 is where its requests go. */
#define CONSOLE (BUF0_W - 16) /* the node what this one prints is sent to; 0: whoever sent the text being served */
#define ROUTE_COUNT (BUF0_W - 17) /* how many entries the table of ways holds */
#define ROUTE_DEFAULT (BUF0_W - 18) /* the port address for a node not in the table, or 0: there is none */
#define LOST (BUF0_W - 19) /* how many messages have been let go for want of a way */
#define PRINT_TO (BUF0_W - 20) /* where what the text being served prints is to go: the node, */
#define PRINT_PORT (BUF0_W - 21) /* and the port address that leads there */
#define DONE_PORT (BUF0_W - 22) /* the port address that leads back to whoever sent the text being served */
#define ROUTES (BUF0_W - 96) /* the table of ways: 16 entries of a node and the port address that leads to it */
#define ROUTE_MAX 16
#define ME (BUF0_W - 13) /* this node's number: a message is for it when its first word is this */
#define OUT_PTR (BUF0_W - 14) /* where the next character printed goes: a cell of the output buffer */
#define REPLY (BUF0_W - 15) /* the address of the port the message being served came on */
@@ -156,6 +165,14 @@ static int host_load(v4_text *tx, v4_node *n, const char *const *files, unsigned
v4_text_constant(tx, "(LINE-STATUS)", LINE_STATUS);
v4_text_constant(tx, "(PORT)", PORT);
v4_text_constant(tx, "(ME)", ME);
v4_text_constant(tx, "(CONSOLE)", CONSOLE);
v4_text_constant(tx, "(ROUTE#)", ROUTE_COUNT);
v4_text_constant(tx, "(ROUTE-DEFAULT)", ROUTE_DEFAULT);
v4_text_constant(tx, "(LOST)", LOST);
v4_text_constant(tx, "(PRINT-TO)", PRINT_TO);
v4_text_constant(tx, "(PRINT-PORT)", PRINT_PORT);
v4_text_constant(tx, "(DONE-PORT)", DONE_PORT);
v4_text_constant(tx, "(ROUTES)", ROUTES);
v4_text_constant(tx, "(OUT^)", OUT_PTR);
v4_text_constant(tx, "(REPLY)", REPLY);
v4_text_constant(tx, "(MSG)", MSG);
v4/tests/test_host_mesh.c
+218
View File
@@ -0,0 +1,218 @@
/* test_host_mesh.c -- StarForth nodes that talk: a console wired to one
* node, and two more in a row behind it. docs/v4.0.0/MESH.md sections 6
* and 7, steps 3 and 4.
*
* console --1 [10] 2--2 [11] 3--2 [12]
*
* Each node is the nucleus (v4/capsule/ *.v4) and nothing else. They start
* alike, numbered 0 and knowing no way anywhere; everything they come to
* know they are told by text sent from the console, as whoever wires a node
* tells it. The console is a device on a port and speaks messages
* (v4/include/v4/message.h).
*/
#include "v4/fabric.h"
#include "v4/message.h"
#include "v4/text.h"
#include <stdio.h>
#include <string.h>
#include "host_map.h"
static int failures = 0, checks = 0;
#define CHECK(c,...) do{checks++; if(!(c)){failures++; printf("FAIL %s:%d: ",__FILE__,__LINE__); printf(__VA_ARGS__); printf("\n");}}while(0)
static v4_text tx;
static v4_node nucleus; /* one node with the nucleus in it: what every node here starts as */
static v4_cell w_idle, w_fault;
static v4_fabric_node pool[3];
static v4_place places[3];
static v4_fabric f;
/* ---- the console: a device on a port ---- */
#define CONSOLE_ID 1
static v4_message going, coming;
static unsigned going_at;
static char printed[8192]; /* what has come back since the console last sent */
static unsigned printed_len;
static v4_cell printed_from; /* which node the last of it came from */
static int ended; /* how many messages of how text ended have come, */
static v4_cell ended_from, ended_how; /* and the last of them */
static int console_give(void *self, v4_cell *value)
{
(void)self;
if (going_at >= going.count) return 0;
*value = going.word[going_at++];
return 1;
}
static int console_take(void *self, v4_cell value)
{
(void)self;
if (v4_message_word(&coming, value)) {
if (v4_message_type(&coming) == V4_MSG_OUTPUT) {
unsigned i, chars = v4_message_length(&coming);
for (i = 0; i < chars && printed_len + 1 < sizeof printed; i++) printed[printed_len++] = v4_message_char(&coming, i);
printed[printed_len] = 0;
printed_from = v4_message_from(&coming);
} else if (v4_message_type(&coming) == V4_MSG_DONE) {
ended++;
ended_from = v4_message_from(&coming);
ended_how = coming.word[V4_MSG_HEADER];
}
coming.count = 0;
}
return 1;
}
static const v4_device console = { console_take, console_give, 0 };
static int is_empty(const char *s) { return s[0] == 0; }
/* Send text to a node and let everything that follows from it happen. */
static const char *tell(v4_cell node, const char *text)
{
unsigned steps = 0;
printed_len = 0; printed[0] = 0; printed_from = -1;
ended = 0; ended_from = -1; ended_how = -1;
if (!v4_message_text(&going, node, CONSOLE_ID, V4_MSG_TEXT, text, (unsigned)strlen(text))) return "(too long)";
going_at = 0;
while (steps < 20000000 && v4_fabric_step(&f) != 0) steps++;
if (steps >= 20000000) return "(still running)";
return printed;
}
/* A StarForth node in the fabric: born, then given the nucleus and the
* registers the nucleus expects, waiting for a message. */
static unsigned starforth_node(unsigned k)
{
int id = v4_fabric_add(&f, &pool[k], PORT);
v4_node *n = &pool[k].n;
memcpy(n->mem, nucleus.mem, sizeof n->mem);
v4_node_stack_regs_attach(n, DSTACK_REG, RSTACK_REG);
v4_node_error_attach(n, NODE_ERROR);
v4_node_fault_attach(n, w_fault);
n->p = w_idle;
return (unsigned)id;
}
static int waiting(unsigned id)
{
const v4_node *n = &v4_fabric_node_at(&f, id)->n;
return n->reading && !n->given && n->read_port == V4_PORT_ANY;
}
int main(void)
{
unsigned hera, mid, far, i;
printf("v4 mesh tests: V4_CELL_BITS=%d, V4_NODE_WORDS=%u\n", V4_CELL_BITS, (unsigned)V4_NODE_WORDS);
{
static const char *const files[] = { "core.v4", "input.v4", "dict.v4", "codegen.v4", "compile.v4", "quit.v4", "forth.v4",
"numout.v4", "words.v4", "system.v4", "qmath.v4", "blocks.v4", "log.v4", "acl.v4" };
CHECK(host_load(&tx, &nucleus, files, 14), "the nucleus assembles");
}
CHECK(v4_text_finish(&tx), "everything is defined: %s", v4_text_error(&tx));
if (failures) { printf(" %d checks, %d failures\n", checks, failures); return 1; }
w_idle = v4_text_word(&tx, "(IDLE)");
w_fault = v4_text_word(&tx, "(FAULTS)");
nucleus.mem[DP] = DICT_W * 4; /* the variables, as at switch-on (tools/mkimage.c) */
nucleus.mem[LATEST] = v4_text_latest(&tx);
nucleus.mem[CFP] = CFS_W;
nucleus.mem[BASE] = 10;
nucleus.mem[FENCE] = DICT_W;
nucleus.mem[BOOT_CELLS] = nucleus.mem[DP];
nucleus.mem[BOOT_CELLS + 1] = nucleus.mem[LATEST];
nucleus.mem[LOG_LEVEL] = 2;
nucleus.mem[CONTEXT] = LATEST;
nucleus.mem[CURRENT] = LATEST;
nucleus.mem[SRC] = TIB;
nucleus.mem[LINE_STATUS] = 1;
nucleus.mem[OUT_PTR] = OUT_W;
v4_fabric_init(&f, places, 3);
hera = starforth_node(0);
mid = starforth_node(1);
far = starforth_node(2);
CHECK(v4_fabric_wire_device(&f, hera, 1, &console), "the console is wired to one node's port 1");
CHECK(v4_fabric_wire(&f, hera, 2, mid, 2) && v4_fabric_wire(&f, mid, 3, far, 2), "and the three nodes in a row");
going.count = 0; going_at = 0;
for (i = 0; i < 20; i++) (void)v4_fabric_step(&f);
CHECK(waiting(hera) && waiting(mid) && waiting(far), "all three wait at their ports");
/* ---- they are told who they are and the way to each other, by text ---- */
CHECK(is_empty(tell(0, "10 (ME) ! 1 (CONSOLE) ! 1 1 ROUTE 0 2 ROUTE")) && ended == 1 && ended_how == V4_TEXT_COMPLETED && ended_from == 10,
"the node at the console takes text sent to 0, and is 10 from then on: %ld", (long)ended_from);
CHECK(is_empty(tell(0, "11 (ME) ! 1 (CONSOLE) ! 2 DEFAULT-ROUTE 0 3 ROUTE")) && ended == 1 && ended_from == 11 && ended_how == V4_TEXT_COMPLETED,
"text sent to 0 now passes through 10 to the next, which is 11 from then on: %ld", (long)ended_from);
CHECK(is_empty(tell(0, "12 (ME) ! 1 (CONSOLE) ! 2 DEFAULT-ROUTE")) && ended == 1 && ended_from == 12 && ended_how == V4_TEXT_COMPLETED,
"and then through both to the last, 12: %ld", (long)ended_from);
CHECK(is_empty(tell(10, "11 2 ROUTE 12 2 ROUTE")) && ended_from == 10 && is_empty(tell(11, "12 3 ROUTE")) && ended_from == 11,
"each is told the way to the others");
/* ---- they talk ---- */
CHECK(strcmp(tell(10, "1 2 + ."), "3 ") == 0 && printed_from == 10 && ended_how == V4_TEXT_COMPLETED, "text for the node at the console is done there");
CHECK(strcmp(tell(11, "20 22 + ."), "42 ") == 0 && printed_from == 11 && ended_from == 11, "text for the next node is done there, and what it prints comes back");
CHECK(strcmp(tell(12, "7 8 * ."), "56 ") == 0 && printed_from == 12 && ended_from == 12 && ended_how == V4_TEXT_COMPLETED,
"text for the last passes through two nodes, and what it prints comes back through two: \"%s\" from %ld", printed, (long)printed_from);
CHECK(strcmp(tell(12, "NOSUCH"), "UNKNOWN WORD: 'NOSUCH'\n") == 0 && ended_from == 12 && ended_how == V4_TEXT_ERROR, "an error there is reported from there");
CHECK(strcmp(tell(12, ": SQ DUP * ;"), "") == 0 && strcmp(tell(12, "9 SQ ."), "81 ") == 0 && strstr(tell(11, "9 SQ ."), "UNKNOWN WORD") != NULL,
"each node has its own dictionary: a word defined on one is not on another");
{
const char *all = tell(12, "WORDS");
CHECK(strlen(all) > 1000 && printed_from == 12 && ended == 1, "more than a message holds comes back in several: %u characters", (unsigned)strlen(all));
}
{
static char line[1100];
memset(line, ' ', 1024);
memcpy(line, "66 EMIT", 7);
memcpy(line + 1017, "67 EMIT", 7);
line[1024] = 0;
CHECK(strcmp(tell(12, line), "BC") == 0, "a message as long as a message may be is passed on whole: 1024 characters");
}
/* ---- one node sends to another ---- */
CHECK(strcmp(tell(10, ": TELL S\" 65 EMIT 12 . \" 12 SEND ; TELL"), "A12 ") == 0 && printed_from == 12,
"text one node SENDs another is done there, and what that prints goes to its console: \"%s\" from %ld", printed, (long)printed_from);
CHECK(strstr(tell(10, ": NOWAY S\" 1\" 99 SEND ; NOWAY"), "Argument out of range") != NULL && ended_how == V4_TEXT_ERROR,
"SEND to a node there is no way to is an error");
/* ---- no way ---- */
CHECK(is_empty(tell(99, "1 2 + .")) && ended == 0, "text for a node there is no way to: nothing comes back");
CHECK(strcmp(tell(10, "(LOST) @ ."), "1 ") == 0, "and the node that could not pass it on has counted it");
CHECK(strcmp(tell(11, "(LOST) @ ."), "0 ") == 0 && strcmp(tell(12, "(LOST) @ ."), "0 ") == 0, "the others have lost nothing");
/* ---- waiting ---- */
{
v4_uheat_t c0 = pool[0].es.anticlock, c1 = pool[1].es.anticlock, c2 = pool[2].es.anticlock;
for (i = 0; i < 100; i++) (void)v4_fabric_step(&f);
CHECK(waiting(hera) && waiting(mid) && waiting(far), "with nothing to do, all three wait at their ports");
CHECK(pool[0].es.anticlock == c0 && pool[1].es.anticlock == c1 && pool[2].es.anticlock == c2, "and execute nothing");
}
/* ---- the ways are forgotten and told again: the wiring has changed ---- */
CHECK(v4_fabric_wire(&f, hera, 3, far, 3), "the far node is wired straight to the one at the console as well");
CHECK(is_empty(tell(10, "NO-ROUTES 1 1 ROUTE 11 2 ROUTE 12 3 ROUTE")) && is_empty(tell(12, "NO-ROUTES 3 DEFAULT-ROUTE")), "and both are told");
{
v4_uheat_t before = pool[1].es.anticlock;
CHECK(strcmp(tell(12, "5 5 + ."), "10 ") == 0 && pool[1].es.anticlock == before, "text for it no longer passes through the middle node, which executes nothing");
}
/* ---- WHAT DOES NOT WORK: two neighbours that write to each other at once ----
* A write blocks until the neighbour reads, and a node that is writing
* is not reading. Here the far node sends text to the middle one and
* then goes to send word of how its own text ended, which goes by the
* middle one; the middle one does the text and goes to answer the far
* one. Each waits for the other to read, for ever. It is the same
* whenever messages go both ways on a wire at once, and it is because
* passing a message on is done here by the node's own programme
* (v4/capsule/quit.v4, (PASS-ON)), which cannot pass anything on while
* it waits to write. docs/v4.0.0/MESH.md, step 4. This check is here
* so that the fault is on record and is seen to go when it is put
* right. */
CHECK(is_empty(tell(10, "NO-ROUTES 1 1 ROUTE 11 2 ROUTE 12 2 ROUTE")) && is_empty(tell(12, "NO-ROUTES 2 DEFAULT-ROUTE")), "the row of three again");
(void)tell(12, ": HI S\" 72 EMIT\" 11 SEND ; HI");
CHECK(pool[1].n.asking && pool[1].n.ask_port == 3 && pool[2].n.asking && pool[2].n.ask_port == 2,
"KNOWN FAULT: two neighbours each writing to the other wait for ever");
printf(" %d checks, %d failures\n", checks, failures);
return failures != 0;
}