#include "includes.h"
static TDB_CONTEXT *tdb;
static int received_signal;
#define MESSAGE_VERSION 1
struct message_rec {
int msg_version;
int msg_type;
pid_t dest;
pid_t src;
size_t len;
};
static struct dispatch_fns {
struct dispatch_fns *next, *prev;
int msg_type;
void (*fn)(int msg_type, pid_t pid, void *buf, size_t len);
} *dispatch_fns;
static void sig_usr1(void)
{
received_signal = 1;
sys_select_signal();
}
static void ping_message(int msg_type, pid_t src, void *buf, size_t len)
{
const char *msg = buf ? buf : "none";
DEBUG(1,("INFO: Received PING message from PID %u [%s]\n",(unsigned int)src, msg));
message_send_pid(src, MSG_PONG, buf, len, True);
}
BOOL message_init(void)
{
if (tdb) return True;
tdb = tdb_open_log(lock_path("messages.tdb"),
0, TDB_CLEAR_IF_FIRST|TDB_DEFAULT,
O_RDWR|O_CREAT,0600);
if (!tdb) {
DEBUG(0,("ERROR: Failed to initialise messages database\n"));
return False;
}
CatchSignal(SIGUSR1, SIGNAL_CAST sig_usr1);
message_register(MSG_PING, ping_message);
register_msg_pool_usage();
register_dmalloc_msgs();
return True;
}
static TDB_DATA message_key_pid(pid_t pid)
{
static char key[20];
TDB_DATA kbuf;
slprintf(key, sizeof(key)-1, "PID/%d", (int)pid);
kbuf.dptr = (char *)key;
kbuf.dsize = strlen(key)+1;
return kbuf;
}
static BOOL message_notify(pid_t pid)
{
SMB_ASSERT(pid > 0);
if (kill(pid, SIGUSR1) == -1) {
if (errno == ESRCH) {
DEBUG(2,("pid %d doesn't exist - deleting messages record\n", (int)pid));
tdb_delete(tdb, message_key_pid(pid));
} else {
DEBUG(2,("message to process %d failed - %s\n", (int)pid, strerror(errno)));
}
return False;
}
return True;
}
static BOOL message_send_pid_internal(pid_t pid, int msg_type, const void *buf, size_t len,
BOOL duplicates_allowed, unsigned int timeout)
{
TDB_DATA kbuf;
TDB_DATA dbuf;
TDB_DATA old_dbuf;
struct message_rec rec;
char *ptr;
struct message_rec prec;
SMB_ASSERT(pid > 0);
rec.msg_version = MESSAGE_VERSION;
rec.msg_type = msg_type;
rec.dest = pid;
rec.src = sys_getpid();
rec.len = len;
kbuf = message_key_pid(pid);
dbuf.dptr = (void *)SMB_MALLOC(len + sizeof(rec));
if (!dbuf.dptr)
return False;
memcpy(dbuf.dptr, &rec, sizeof(rec));
if (len > 0)
memcpy((void *)((char*)dbuf.dptr+sizeof(rec)), buf, len);
dbuf.dsize = len + sizeof(rec);
if (duplicates_allowed) {
if (timeout) {
if (tdb_chainlock_with_timeout(tdb, kbuf, timeout) == -1) {
DEBUG(0,("message_send_pid_internal: failed to get chainlock with timeout %ul.\n", timeout));
return False;
}
} else {
if (tdb_chainlock(tdb, kbuf) == -1) {
DEBUG(0,("message_send_pid_internal: failed to get chainlock.\n"));
return False;
}
}
tdb_append(tdb, kbuf, dbuf);
tdb_chainunlock(tdb, kbuf);
SAFE_FREE(dbuf.dptr);
errno = 0;
return message_notify(pid);
}
if (timeout) {
if (tdb_chainlock_with_timeout(tdb, kbuf, timeout) == -1) {
DEBUG(0,("message_send_pid_internal: failed to get chainlock with timeout %ul.\n", timeout));
return False;
}
} else {
if (tdb_chainlock(tdb, kbuf) == -1) {
DEBUG(0,("message_send_pid_internal: failed to get chainlock.\n"));
return False;
}
}
old_dbuf = tdb_fetch(tdb, kbuf);
if (!old_dbuf.dptr) {
tdb_store(tdb, kbuf, dbuf, TDB_REPLACE);
tdb_chainunlock(tdb, kbuf);
SAFE_FREE(dbuf.dptr);
errno = 0;
return message_notify(pid);
}
for(ptr = (char *)old_dbuf.dptr; ptr < old_dbuf.dptr + old_dbuf.dsize; ) {
if (!memcmp(ptr, &rec, sizeof(rec))) {
if (!len || (len && !memcmp( ptr + sizeof(rec), buf, len))) {
tdb_chainunlock(tdb, kbuf);
DEBUG(10,("message_send_pid_internal: discarding duplicate message.\n"));
SAFE_FREE(dbuf.dptr);
SAFE_FREE(old_dbuf.dptr);
return True;
}
}
memcpy(&prec, ptr, sizeof(prec));
ptr += sizeof(rec) + prec.len;
}
tdb_append(tdb, kbuf, dbuf);
tdb_chainunlock(tdb, kbuf);
SAFE_FREE(old_dbuf.dptr);
SAFE_FREE(dbuf.dptr);
errno = 0;
return message_notify(pid);
}
BOOL message_send_pid(pid_t pid, int msg_type, const void *buf, size_t len, BOOL duplicates_allowed)
{
return message_send_pid_internal(pid, msg_type, buf, len, duplicates_allowed, 0);
}
BOOL message_send_pid_with_timeout(pid_t pid, int msg_type, const void *buf, size_t len,
BOOL duplicates_allowed, unsigned int timeout)
{
return message_send_pid_internal(pid, msg_type, buf, len, duplicates_allowed, timeout);
}
unsigned int messages_pending_for_pid(pid_t pid)
{
TDB_DATA kbuf;
TDB_DATA dbuf;
char *buf;
unsigned int message_count = 0;
kbuf = message_key_pid(sys_getpid());
dbuf = tdb_fetch(tdb, kbuf);
if (dbuf.dptr == NULL || dbuf.dsize == 0) {
SAFE_FREE(dbuf.dptr);
return 0;
}
for (buf = dbuf.dptr; dbuf.dsize > sizeof(struct message_rec);) {
struct message_rec rec;
memcpy(&rec, buf, sizeof(rec));
buf += (sizeof(rec) + rec.len);
dbuf.dsize -= (sizeof(rec) + rec.len);
message_count++;
}
SAFE_FREE(dbuf.dptr);
return message_count;
}
static BOOL retrieve_all_messages(char **msgs_buf, size_t *total_len)
{
TDB_DATA kbuf;
TDB_DATA dbuf;
TDB_DATA null_dbuf;
ZERO_STRUCT(null_dbuf);
*msgs_buf = NULL;
*total_len = 0;
kbuf = message_key_pid(sys_getpid());
if (tdb_chainlock(tdb, kbuf) == -1)
return False;
dbuf = tdb_fetch(tdb, kbuf);
tdb_store(tdb, kbuf, null_dbuf, TDB_REPLACE);
tdb_chainunlock(tdb, kbuf);
if (dbuf.dptr == NULL || dbuf.dsize == 0) {
SAFE_FREE(dbuf.dptr);
return False;
}
*msgs_buf = dbuf.dptr;
*total_len = dbuf.dsize;
return True;
}
static BOOL message_recv(char *msgs_buf, size_t total_len, int *msg_type, pid_t *src, char **buf, size_t *len)
{
struct message_rec rec;
char *ret_buf = *buf;
*buf = NULL;
*len = 0;
if (total_len - (ret_buf - msgs_buf) < sizeof(rec))
return False;
memcpy(&rec, ret_buf, sizeof(rec));
ret_buf += sizeof(rec);
if (rec.msg_version != MESSAGE_VERSION) {
DEBUG(0,("message version %d received (expected %d)\n", rec.msg_version, MESSAGE_VERSION));
return False;
}
if (rec.len > 0) {
if (total_len - (ret_buf - msgs_buf) < rec.len)
return False;
}
*len = rec.len;
*msg_type = rec.msg_type;
*src = rec.src;
*buf = ret_buf;
return True;
}
void message_dispatch(void)
{
int msg_type;
pid_t src;
char *buf;
char *msgs_buf;
size_t len, total_len;
struct dispatch_fns *dfn;
int n_handled;
if (!received_signal)
return;
DEBUG(10,("message_dispatch: received_signal = %d\n", received_signal));
received_signal = 0;
if (!retrieve_all_messages(&msgs_buf, &total_len))
return;
for (buf = msgs_buf; message_recv(msgs_buf, total_len, &msg_type, &src, &buf, &len); buf += len) {
DEBUG(10,("message_dispatch: received msg_type=%d src_pid=%u\n",
msg_type, (unsigned int) src));
n_handled = 0;
for (dfn = dispatch_fns; dfn; dfn = dfn->next) {
if (dfn->msg_type == msg_type) {
DEBUG(10,("message_dispatch: processing message of type %d.\n", msg_type));
dfn->fn(msg_type, src, len ? (void *)buf : NULL, len);
n_handled++;
}
}
if (!n_handled) {
DEBUG(5,("message_dispatch: warning: no handlers registed for "
"msg_type %d in pid %u\n",
msg_type, (unsigned int)sys_getpid()));
}
}
SAFE_FREE(msgs_buf);
}
void message_register(int msg_type,
void (*fn)(int msg_type, pid_t pid, void *buf, size_t len))
{
struct dispatch_fns *dfn;
dfn = SMB_MALLOC_P(struct dispatch_fns);
if (dfn != NULL) {
ZERO_STRUCTPN(dfn);
dfn->msg_type = msg_type;
dfn->fn = fn;
DLIST_ADD(dispatch_fns, dfn);
}
else {
DEBUG(0,("message_register: Not enough memory. malloc failed!\n"));
}
}
void message_deregister(int msg_type)
{
struct dispatch_fns *dfn, *next;
for (dfn = dispatch_fns; dfn; dfn = next) {
next = dfn->next;
if (dfn->msg_type == msg_type) {
DLIST_REMOVE(dispatch_fns, dfn);
SAFE_FREE(dfn);
}
}
}
struct msg_all {
int msg_type;
uint32 msg_flag;
const void *buf;
size_t len;
BOOL duplicates;
int n_sent;
};
static int traverse_fn(TDB_CONTEXT *the_tdb, TDB_DATA kbuf, TDB_DATA dbuf, void *state)
{
struct connections_data crec;
struct msg_all *msg_all = (struct msg_all *)state;
if (dbuf.dsize != sizeof(crec))
return 0;
memcpy(&crec, dbuf.dptr, sizeof(crec));
if (crec.cnum != -1)
return 0;
if(!(crec.bcast_msg_flags & msg_all->msg_flag))
return 0;
if (!message_send_pid(crec.pid, msg_all->msg_type,
msg_all->buf, msg_all->len,
msg_all->duplicates)) {
if (errno == ESRCH) {
DEBUG(2,("pid %u doesn't exist - deleting connections %d [%s]\n",
(unsigned int)crec.pid, crec.cnum, crec.name));
tdb_delete(the_tdb, kbuf);
}
}
msg_all->n_sent++;
return 0;
}
BOOL message_send_all(TDB_CONTEXT *conn_tdb, int msg_type,
const void *buf, size_t len,
BOOL duplicates_allowed,
int *n_sent)
{
struct msg_all msg_all;
msg_all.msg_type = msg_type;
if (msg_type < 1000)
msg_all.msg_flag = FLAG_MSG_GENERAL;
else if (msg_type > 1000 && msg_type < 2000)
msg_all.msg_flag = FLAG_MSG_NMBD;
else if (msg_type > 2000 && msg_type < 2100)
msg_all.msg_flag = FLAG_MSG_PRINT_NOTIFY;
else if (msg_type > 2100 && msg_type < 3000)
msg_all.msg_flag = FLAG_MSG_PRINT_GENERAL;
else if (msg_type > 3000 && msg_type < 4000)
msg_all.msg_flag = FLAG_MSG_SMBD;
else
return False;
msg_all.buf = buf;
msg_all.len = len;
msg_all.duplicates = duplicates_allowed;
msg_all.n_sent = 0;
tdb_traverse(conn_tdb, traverse_fn, &msg_all);
if (n_sent)
*n_sent = msg_all.n_sent;
return True;
}