diff options
| -rw-r--r-- | README | 59 | ||||
| -rw-r--r-- | sbusd.c | 43 | ||||
| -rw-r--r-- | test.c | 1 |
3 files changed, 102 insertions, 1 deletions
@@ -133,3 +133,62 @@ Secret messages: B: Send B's credentials with routing key private to A. A: Send a random message with routing key private to B. B: Send back the message with routing key private to A. + +Flood control: + The following control messages can be sent to the server to + choose the server behaviour when messages cannot be delivered + without blocking. All control messages are optional and server + may choose to ignore them at any time, even if previously + honoured. Most recently sent control message that precedence. + + ^CMSG blocking/soft/queue\(\x00.*\)*$ + + Delivering is preferable, the server should queue up + message that cannot be sent. + + ^CMSG blocking/soft/discard\(\x00.*\)*$ + + Delivering is unimportant, the server should discard + message that cannot be sent. + + ^CMSG blocking/soft/block\(\x00.*\)*$ + + Delivering is important, the server may block communication + to guarantee that messages are delivered. + + ^CMSG blocking/soft/error\(\x00.*\)*$ + + The server may treat a client as misbehaving if message + cannot be sent. + + ^CMSG blocking/hard/discard\(\x00.*\)*$ + + If the server has queued up too many message it should + start discarding new message instead of queuing them. + + ^CMSG blocking/hard/block\(\x00.*\)*$ + + If the server has queued up too many message it should + start blocking communication until it can start queuing + messages again. + + ^CMSG blocking/hard/error\(\x00.*\)*$ + + If the server has queued up too many message it should + start treating clients that are blocking as misbehaving. + + ^CMSG order/queue\(\x00.*\)*$ + + If the client is blocking it is preferable that messages + are sent in order. + + ^CMSG order/stack\(\x00.*\)*$ + + If the client is blocking it is preferable that messages + are sent in reverse order. + + ^CMSG order/random\(\x00.*\)*$ + + If the client is blocking it is preferable that messages + are sent in such order that memory is freed up as fast + as possible. @@ -24,8 +24,26 @@ #define STYPE_MAX(T) (long long int)((1ULL << (8 * sizeof(T) - 1)) - 1) #define eprintf(...) (weprintf(__VA_ARGS__), exit(1)) +enum blocking_mode { + BLOCKING_QUEUE, + BLOCKING_DISCARD, + BLOCKING_BLOCK, + BLOCKING_ERROR +}; + +enum order { + ORDER_QUEUE = 0, + ORDER_STACK = 1, + ORDER_RANDOM_QUEUE = 2, + ORDER_RANDOM_STACK = 3, +}; +#define ORDER_RANDOM 2 + struct client { int fd; + enum blocking_mode soft_blocking_mode; + enum blocking_mode hard_blocking_mode; + enum order order; char **subs; size_t nsubs; size_t subs_siz; @@ -84,6 +102,9 @@ add_client(int fd) if (!cl) return NULL; cl->fd = fd; + cl->soft_blocking_mode = BLOCKING_QUEUE; + cl->hard_blocking_mode = BLOCKING_DISCARD; + cl->order = ORDER_RANDOM_QUEUE; cl->subs = NULL; cl->nsubs = 0; cl->subs_siz = 0; @@ -266,7 +287,7 @@ remove_subscription(struct client *cl, const char *key) static int send_packet(struct client *cl, const char *buf, size_t n) { - /* TODO queue instead of block */ + /* TODO honour cl->soft_blocking_mode, cl->hard_blocking_mode, and cl->order */ return -(send(cl->fd, buf, n, 0) < 0); } @@ -275,6 +296,26 @@ handle_cmsg(struct client *cl, const char *msg, size_t n) { if (!strcmp(msg, "CMSG !/cred/prefix")) { n = sizeof("CMSG !/cred/prefix"); + } else if (!strcmp(msg, "CMSG blocking/soft/queue")) { + cl->soft_blocking_mode = BLOCKING_QUEUE; + } else if (!strcmp(msg, "CMSG blocking/soft/discard")) { + cl->soft_blocking_mode = BLOCKING_DISCARD; + } else if (!strcmp(msg, "CMSG blocking/soft/block")) { + cl->soft_blocking_mode = BLOCKING_BLOCK; + } else if (!strcmp(msg, "CMSG blocking/soft/error")) { + cl->soft_blocking_mode = BLOCKING_ERROR; + } else if (!strcmp(msg, "CMSG blocking/hard/discard")) { + cl->hard_blocking_mode = BLOCKING_DISCARD; + } else if (!strcmp(msg, "CMSG blocking/hard/block")) { + cl->hard_blocking_mode = BLOCKING_BLOCK; + } else if (!strcmp(msg, "CMSG blocking/hard/error")) { + cl->hard_blocking_mode = BLOCKING_ERROR; + } else if (!strcmp(msg, "CMSG order/queue")) { + cl->order = ORDER_QUEUE; + } else if (!strcmp(msg, "CMSG order/stack")) { + cl->order = ORDER_STACK; + } else if (!strcmp(msg, "CMSG order/random")) { + cl->order |= ORDER_RANDOM; } else { return; } @@ -355,3 +355,4 @@ main(void) /* TODO untested sbusd flags: -p[/dev/null] (-f) -u */ /* TODO test credentials */ +/* TODO test CMSG server */ |