[thirdparty/squid.git] / src / helper.cc

#include "squid.h"

#define HELPER_MAX_ARGS 64

static PF helperHandleRead;
static PF helperServerFree;
static void Enqueue(helper * hlp, helper_request *);
static helper_request *Dequeue(helper * hlp);
static helper_server *GetFirstAvailable(helper * hlp);
static void helperDispatch(helper_server * srv, helper_request * r);
static void helperKickQueue(helper * hlp);
static void helperRequestFree(helper_request * r);


void
helperOpenServers(helper * hlp)
{
    char *s;
    char *progname;
    char *shortname;
    char *procname;
    char *args[HELPER_MAX_ARGS];
    char fd_note_buf[FD_DESC_SZ];
    helper_server *srv;
    int nargs = 0;
    int k;
    int x;
    int rfd;
    int wfd;
    wordlist *w;
    if (hlp->cmdline == NULL)
	return;
    progname = hlp->cmdline->key;
    assert(hlp->servers.head == NULL);
    assert(hlp->servers.tail == NULL);
    if ((s = strrchr(progname, '/')))
	shortname = xstrdup(s + 1);
    else
	shortname = xstrdup(progname);
    debug(29, 1) ("helperOpenServers: Starting %d '%s' processes\n",
	hlp->n_to_start, shortname);
    procname = xmalloc(strlen(shortname) + 3);
    snprintf(procname, strlen(shortname) + 3, "(%s)", shortname);
    args[nargs++] = procname;
    for (w = hlp->cmdline->next; w && nargs < HELPER_MAX_ARGS; w = w->next)
	args[nargs++] = w->key;
    args[nargs++] = NULL;
    assert(nargs <= HELPER_MAX_ARGS);
    for (k = 0; k < hlp->n_to_start; k++) {
	rfd = wfd = -1;
	x = ipcCreate(hlp->ipc_type,
	    progname,
	    args,
	    shortname,
	    &rfd,
	    &wfd);
	if (x < 0) {
	    debug(29, 1) ("WARNING: Cannot run '%s' process.\n", progname);
	    continue;
	}
	hlp->n_running++;
	srv = xcalloc(1, sizeof(*srv));
	cbdataAdd(srv, MEM_NONE);
	srv->flags.alive = 1;
	srv->index = k;
	srv->rfd = rfd;
	srv->wfd = wfd;
	srv->buf = memAllocate(MEM_8K_BUF);
	srv->buf_sz = 8192;
	srv->offset = 0;
	srv->parent = hlp;
	cbdataLock(hlp);	/* lock because of the parent backlink */
	dlinkAddTail(srv, &srv->link, &hlp->servers);
	if (rfd == wfd) {
	    snprintf(fd_note_buf, FD_DESC_SZ, "%s #%d", shortname, k + 1);
	    fd_note(rfd, fd_note_buf);
	} else {
	    snprintf(fd_note_buf, FD_DESC_SZ, "reading %s #%d", shortname, k + 1);
	    fd_note(rfd, fd_note_buf);
	    snprintf(fd_note_buf, FD_DESC_SZ, "writing %s #%d", shortname, k + 1);
	    fd_note(wfd, fd_note_buf);
	}
	commSetNonBlocking(rfd);
	if (wfd != rfd)
	    commSetNonBlocking(wfd);
	comm_add_close_handler(rfd, helperServerFree, srv);
    }
    safe_free(shortname);
    safe_free(procname);
}

void
helperSubmit(helper * hlp, const char *buf, HLPCB * callback, void *data)
{
    helper_request *r = xcalloc(1, sizeof(*r));
    helper_server *srv;
    r->callback = callback;
    r->data = data;
    r->buf = xstrdup(buf);
    cbdataLock(r->data);
    if ((srv = GetFirstAvailable(hlp)))
	helperDispatch(srv, r);
    else
	Enqueue(hlp, r);
}

void
helperStats(StoreEntry * sentry, helper * hlp)
{
    helper_server *srv;
    dlink_node *link;
    storeAppendPrintf(sentry, "number running: %d of %d\n",
	hlp->n_running, hlp->n_to_start);
    storeAppendPrintf(sentry, "requests sent: %d\n",
	hlp->stats.requests);
    storeAppendPrintf(sentry, "replies received: %d\n",
	hlp->stats.replies);
    storeAppendPrintf(sentry, "queue length: %d\n",
	hlp->stats.queue_size);
    storeAppendPrintf(sentry, "avg service time: %d msec\n",
	hlp->stats.avg_svc_time);
    storeAppendPrintf(sentry, "\n");
    storeAppendPrintf(sentry, "%7s\t%7s\t%11s\t%s\t%7s\t%7s\n",
	"#",
	"FD",
	"# Requests",
	"Flags",
	"Time",
	"Offset");
    for (link = hlp->servers.head; link; link = link->next) {
	srv = link->data;
	storeAppendPrintf(sentry, "%7d\t%7d\t%11d\t%c%c%c%c\t%7.3f\t%7d\n",
	    srv->index + 1,
	    srv->rfd,
	    srv->stats.uses,
	    srv->flags.alive ? 'A' : ' ',
	    srv->flags.busy ? 'B' : ' ',
	    srv->flags.closing ? 'C' : ' ',
	    srv->flags.shutdown ? 'S' : ' ',
	    0.001 * tvSubMsec(srv->dispatch_time, current_time),
	    (int) srv->offset);
    }
    storeAppendPrintf(sentry, "\nFlags key:\n\n");
    storeAppendPrintf(sentry, "   A = ALIVE\n");
    storeAppendPrintf(sentry, "   B = BUSY\n");
    storeAppendPrintf(sentry, "   C = CLOSING\n");
    storeAppendPrintf(sentry, "   S = SHUTDOWN\n");
}

void
helperShutdown(helper * hlp)
{
    dlink_node *link;
    helper_server *srv;
    for (link = hlp->servers.head; link; link = link->next) {
	srv = link->data;
	if (!srv->flags.alive) {
	    debug(34, 3) ("helperShutdown: %s #%d is NOT ALIVE.\n",
		hlp->id_name, srv->index + 1);
	    continue;
	}
	srv->flags.shutdown = 1;	/* request it to shut itself down */
	if (srv->flags.busy) {
	    debug(34, 3) ("helperShutdown: %s #%d is BUSY.\n",
		hlp->id_name, srv->index + 1);
	    continue;
	}
	if (srv->flags.closing) {
	    debug(34, 3) ("helperShutdown: %s #%d is CLOSING.\n",
		hlp->id_name, srv->index + 1);
	    continue;
	}
	srv->flags.closing = 1;
	comm_close(srv->wfd);
    }
}

helper *
helperCreate(const char *name)
{
    helper *hlp = xcalloc(1, sizeof(*hlp));
    cbdataAdd(hlp, MEM_NONE);
    hlp->id_name = name;
    return hlp;
}

void
helperFree(helper * hlp)
{
    /* note, don't free hlp->name, it probably points to static memory */
    if (hlp->queue.head)
	debug(29, 0) ("WARNING: freeing %s helper with %d requests queued\n",
	    hlp->id_name, hlp->stats.queue_size);
    cbdataFree(hlp);
}

/* ====================================================================== */
/* LOCAL FUNCTIONS */
/* ====================================================================== */

static void
helperServerFree(int fd, void *data)
{
    helper_server *srv = data;
    helper *hlp = srv->parent;
    assert(srv->rfd == fd);
    if (srv->buf) {
	memFree(MEM_8K_BUF, srv->buf);
	srv->buf = NULL;
    }
    if (srv->wfd != srv->rfd)
	comm_close(srv->wfd);
    dlinkDelete(&srv->link, &hlp->servers);
    hlp->n_running--;
    assert(hlp->n_running >= 0);
    if (!srv->flags.shutdown) {
	debug(34, 0) ("WARNING: %s #%d (FD %d) exited\n",
	    hlp->id_name, srv->index + 1, fd);
	assert(hlp->n_running >= hlp->n_to_start / 2);
	if (hlp->n_running < hlp->n_to_start / 2)
	    fatalf("Too few %s processes are running", hlp->id_name);
    }
    cbdataUnlock(srv->parent);
    cbdataFree(srv);
}

static void
helperHandleRead(int fd, void *data)
{
    int len;
    char *t = NULL;
    helper_server *srv = data;
    helper_request *r;
    helper *hlp = srv->parent;
    assert(fd == srv->rfd);
    assert(cbdataValid(data));
    Counter.syscalls.sock.reads++;
    len = read(fd, srv->buf + srv->offset, srv->buf_sz - srv->offset);
    fd_bytes(fd, len, FD_READ);
    debug(29, 5) ("helperHandleRead: %d bytes from %s #%d.\n",
	len, hlp->id_name, srv->index + 1);
    if (len <= 0) {
	if (len < 0)
	    debug(50, 1) ("helperHandleRead: FD %d read: %s\n", fd, xstrerror());
	comm_close(fd);
	return;
    }
    srv->offset += len;
    srv->buf[srv->offset] = '\0';
    r = srv->request;
    if (r == NULL) {
	/* someone spoke without being spoken to */
	debug(29, 1) ("helperHandleRead: unexpected read from %s #%d, %d bytes\n",
	    hlp->id_name, srv->index + 1, len);
	srv->offset = 0;
    } else if ((t = strchr(srv->buf, '\n'))) {
	/* end of reply found */
	debug(29, 3) ("helperHandleRead: end of reply found\n");
	*t = '\0';
	if (cbdataValid(r->data))
	    r->callback(r->data, srv->buf);
	srv->flags.busy = 0;
	srv->offset = 0;
	helperRequestFree(r);
	hlp->stats.replies++;
	hlp->stats.avg_svc_time =
	    intAverage(hlp->stats.avg_svc_time,
	    tvSubMsec(srv->dispatch_time, current_time),
	    hlp->stats.replies, REDIRECT_AV_FACTOR);
	if (srv->flags.shutdown)
	    comm_close(srv->wfd);
    } else {
	commSetSelect(srv->rfd, COMM_SELECT_READ, helperHandleRead, srv, 0);
    }
    helperKickQueue(hlp);
}

static void
Enqueue(helper * hlp, helper_request * r)
{
    dlink_node *link = xcalloc(1, sizeof(*link));
    dlinkAddTail(r, link, &hlp->queue);
    hlp->stats.queue_size++;
    if (hlp->stats.queue_size < hlp->n_running)
	return;
    if (squid_curtime - hlp->last_queue_warn < 600)
	return;
    if (shutting_down || reconfiguring)
	return;
    hlp->last_queue_warn = squid_curtime;
    debug(14, 0) ("WARNING: All %s processes are busy.\n", hlp->id_name);
    debug(14, 0) ("WARNING: %d pending requests queued\n", hlp->stats.queue_size);
    if (hlp->stats.queue_size > hlp->n_running * 2)
	fatalf("Too many queued %s requests", hlp->id_name);
    debug(14, 1) ("Consider increasing the number of %s processes in your config file.\n", hlp->id_name);
}

static helper_request *
Dequeue(helper * hlp)
{
    dlink_node *link;
    helper_request *r = NULL;
    if ((link = hlp->queue.head)) {
	r = link->data;
	dlinkDelete(link, &hlp->queue);
	safe_free(link);
	hlp->stats.queue_size--;
    }
    return r;
}

static helper_server *
GetFirstAvailable(helper * hlp)
{
    dlink_node *n;
    helper_server *srv = NULL;
    if (hlp->n_running == 0)
	return NULL;
    for (n = hlp->servers.head; n != NULL; n = n->next) {
	srv = n->data;
	if (srv->flags.busy)
	    continue;
	if (!srv->flags.alive)
	    continue;
	return srv;
    }
    return NULL;
}

static void
helperDispatch(helper_server * srv, helper_request * r)
{
    helper *hlp = srv->parent;
    if (!cbdataValid(r->data)) {
	debug(29, 1) ("helperDispatch: invalid callback data\n");
	helperRequestFree(r);
	return;
    }
    assert(!srv->flags.busy);
    srv->flags.busy = 1;
    srv->request = r;
    srv->dispatch_time = current_time;
    comm_write(srv->wfd,
	r->buf,
	strlen(r->buf),
	NULL,			/* Handler */
	NULL,			/* Handler-data */
	NULL);			/* free */
    commSetSelect(srv->rfd,
	COMM_SELECT_READ,
	helperHandleRead,
	srv, 0);
    debug(29, 5) ("helperDispatch: Request sent to %s #%d, %d bytes\n",
	hlp->id_name, srv->index + 1, strlen(r->buf));
    srv->stats.uses++;
    hlp->stats.requests++;
}

static void
helperKickQueue(helper * hlp)
{
    helper_request *r;
    helper_server *srv;
    while ((srv = GetFirstAvailable(hlp)) && (r = Dequeue(hlp)))
	helperDispatch(srv, r);
}

static void
helperRequestFree(helper_request * r)
{
    cbdataUnlock(r->data);
    xfree(r->buf);
    xfree(r);
}
Commit	Line	Data
74addf6c	1	#include "squid.h"
	2
	3	#define HELPER_MAX_ARGS 64
	4
	5	static PF helperHandleRead;
1f5f60dd	6	static PF helperServerFree;
74addf6c	7	static void Enqueue(helper * hlp, helper_request *);
	8	static helper_request Dequeue(helper hlp);
	9	static helper_server GetFirstAvailable(helper hlp);
	10	static void helperDispatch(helper_server * srv, helper_request * r);
	11	static void helperKickQueue(helper * hlp);
	12	static void helperRequestFree(helper_request * r);
	13
	14
	15	void
	16	helperOpenServers(helper * hlp)
	17	{
	18	char *s;
	19	char *progname;
	20	char *shortname;
	21	char *procname;
	22	char *args[HELPER_MAX_ARGS];
	23	char fd_note_buf[FD_DESC_SZ];
	24	helper_server *srv;
	25	int nargs = 0;
	26	int k;
	27	int x;
	28	int rfd;
	29	int wfd;
	30	wordlist *w;
	31	if (hlp->cmdline == NULL)
	32	return;
	33	progname = hlp->cmdline->key;
	34	assert(hlp->servers.head == NULL);
	35	assert(hlp->servers.tail == NULL);
	36	if ((s = strrchr(progname, '/')))
	37	shortname = xstrdup(s + 1);
	38	else
	39	shortname = xstrdup(progname);
	40	debug(29, 1) ("helperOpenServers: Starting %d '%s' processes\n",
	41	hlp->n_to_start, shortname);
	42	procname = xmalloc(strlen(shortname) + 3);
	43	snprintf(procname, strlen(shortname) + 3, "(%s)", shortname);
	44	args[nargs++] = procname;
	45	for (w = hlp->cmdline->next; w && nargs < HELPER_MAX_ARGS; w = w->next)
	46	args[nargs++] = w->key;
	47	args[nargs++] = NULL;
	48	assert(nargs <= HELPER_MAX_ARGS);
	49	for (k = 0; k < hlp->n_to_start; k++) {
	50	rfd = wfd = -1;
	51	x = ipcCreate(hlp->ipc_type,
	52	progname,
	53	args,
	54	shortname,
	55	&rfd,
	56	&wfd);
	57	if (x < 0) {
	58	debug(29, 1) ("WARNING: Cannot run '%s' process.\n", progname);
	59	continue;
	60	}
	61	hlp->n_running++;
	62	srv = xcalloc(1, sizeof(*srv));
	63	cbdataAdd(srv, MEM_NONE);
	64	srv->flags.alive = 1;
	65	srv->index = k;
	66	srv->rfd = rfd;
	67	srv->wfd = wfd;
	68	srv->buf = memAllocate(MEM_8K_BUF);
	69	srv->buf_sz = 8192;
	70	srv->offset = 0;
71	srv->parent = hlp;
1f5f60dd	72	cbdataLock(hlp); /* lock because of the parent backlink */
74addf6c	73	dlinkAddTail(srv, &srv->link, &hlp->servers);
	74	if (rfd == wfd) {
	75	snprintf(fd_note_buf, FD_DESC_SZ, "%s #%d", shortname, k + 1);
	76	fd_note(rfd, fd_note_buf);
	77	} else {
	78	snprintf(fd_note_buf, FD_DESC_SZ, "reading %s #%d", shortname, k + 1);
	79	fd_note(rfd, fd_note_buf);
	80	snprintf(fd_note_buf, FD_DESC_SZ, "writing %s #%d", shortname, k + 1);
	81	fd_note(wfd, fd_note_buf);
	82	}
	83	commSetNonBlocking(rfd);
	84	if (wfd != rfd)
	85	commSetNonBlocking(wfd);
1f5f60dd	86	comm_add_close_handler(rfd, helperServerFree, srv);
74addf6c	87	}
	88	safe_free(shortname);
	89	safe_free(procname);
	90	}
	91
	92	void
	93	helperSubmit(helper * hlp, const char buf, HLPCB callback, void *data)
	94	{
	95	helper_request r = xcalloc(1, sizeof(r));
	96	helper_server *srv;
	97	r->callback = callback;
	98	r->data = data;
	99	r->buf = xstrdup(buf);
	100	cbdataLock(r->data);
	101	if ((srv = GetFirstAvailable(hlp)))
	102	helperDispatch(srv, r);
	103	else
	104	Enqueue(hlp, r);
	105	}
	106
	107	void
	108	helperStats(StoreEntry * sentry, helper * hlp)
	109	{
	110	helper_server *srv;
	111	dlink_node *link;
	112	storeAppendPrintf(sentry, "number running: %d of %d\n",
	113	hlp->n_running, hlp->n_to_start);
	114	storeAppendPrintf(sentry, "requests sent: %d\n",
	115	hlp->stats.requests);
	116	storeAppendPrintf(sentry, "replies received: %d\n",
	117	hlp->stats.replies);
	118	storeAppendPrintf(sentry, "queue length: %d\n",
	119	hlp->stats.queue_size);
	120	storeAppendPrintf(sentry, "avg service time: %d msec\n",
	121	hlp->stats.avg_svc_time);
	122	storeAppendPrintf(sentry, "\n");
	123	storeAppendPrintf(sentry, "%7s\t%7s\t%11s\t%s\t%7s\t%7s\n",
	124	"#",
	125	"FD",
	126	"# Requests",
	127	"Flags",
	128	"Time",
	129	"Offset");
	130	for (link = hlp->servers.head; link; link = link->next) {
	131	srv = link->data;
	132	storeAppendPrintf(sentry, "%7d\t%7d\t%11d\t%c%c%c%c\t%7.3f\t%7d\n",
	133	srv->index + 1,
	134	srv->rfd,
	135	srv->stats.uses,
	136	srv->flags.alive ? 'A' : ' ',
	137	srv->flags.busy ? 'B' : ' ',
	138	srv->flags.closing ? 'C' : ' ',
	139	srv->flags.shutdown ? 'S' : ' ',
	140	0.001 * tvSubMsec(srv->dispatch_time, current_time),
	141	(int) srv->offset);
	142	}
	143	storeAppendPrintf(sentry, "\nFlags key:\n\n");
	144	storeAppendPrintf(sentry, " A = ALIVE\n");
	145	storeAppendPrintf(sentry, " B = BUSY\n");
	146	storeAppendPrintf(sentry, " C = CLOSING\n");
	147	storeAppendPrintf(sentry, " S = SHUTDOWN\n");
	148	}
	149
	150	void
151	helperShutdown(helper * hlp)
152	{
153	dlink_node *link;
154	helper_server *srv;
155	for (link = hlp->servers.head; link; link = link->next) {
156	srv = link->data;
157	if (!srv->flags.alive) {
158	debug(34, 3) ("helperShutdown: %s #%d is NOT ALIVE.\n",
159	hlp->id_name, srv->index + 1);
160	continue;
161	}
1f5f60dd	162	srv->flags.shutdown = 1; /* request it to shut itself down */
74addf6c	163	if (srv->flags.busy) {
	164	debug(34, 3) ("helperShutdown: %s #%d is BUSY.\n",
	165	hlp->id_name, srv->index + 1);
74addf6c	166	continue;
	167	}
	168	if (srv->flags.closing) {
	169	debug(34, 3) ("helperShutdown: %s #%d is CLOSING.\n",
	170	hlp->id_name, srv->index + 1);
	171	continue;
	172	}
74addf6c	173	srv->flags.closing = 1;
1f5f60dd	174	comm_close(srv->wfd);
74addf6c	175	}
	176	}
	177
1f5f60dd	178	helper *
	179	helperCreate(const char *name)
	180	{
	181	helper hlp = xcalloc(1, sizeof(hlp));
	182	cbdataAdd(hlp, MEM_NONE);
	183	hlp->id_name = name;
	184	return hlp;
	185	}
	186
	187	void
	188	helperFree(helper * hlp)
	189	{
	190	/* note, don't free hlp->name, it probably points to static memory */
fe73896c	191	if (hlp->queue.head)
	192	debug(29, 0) ("WARNING: freeing %s helper with %d requests queued\n",
	193	hlp->id_name, hlp->stats.queue_size);
1f5f60dd	194	cbdataFree(hlp);
	195	}
	196
74addf6c	197	/* ====================================================================== */
	198	/* LOCAL FUNCTIONS */
	199	/* ====================================================================== */
	200
	201	static void
1f5f60dd	202	helperServerFree(int fd, void *data)
74addf6c	203	{
	204	helper_server *srv = data;
	205	helper *hlp = srv->parent;
	206	assert(srv->rfd == fd);
	207	if (srv->buf) {
	208	memFree(MEM_8K_BUF, srv->buf);
	209	srv->buf = NULL;
	210	}
	211	if (srv->wfd != srv->rfd)
	212	comm_close(srv->wfd);
	213	dlinkDelete(&srv->link, &hlp->servers);
74addf6c	214	hlp->n_running--;
74addf6c	215	assert(hlp->n_running >= 0);
1f5f60dd	216	if (!srv->flags.shutdown) {
1f5f60dd	217	debug(34, 0) ("WARNING: %s #%d (FD %d) exited\n",
14e87a44	218	hlp->id_name, srv->index + 1, fd);
1f5f60dd	219	assert(hlp->n_running >= hlp->n_to_start / 2);
1f5f60dd	220	if (hlp->n_running < hlp->n_to_start / 2)
14e87a44	221	fatalf("Too few %s processes are running", hlp->id_name);
14e87a44	222	}
1f5f60dd	223	cbdataUnlock(srv->parent);
14e87a44	224	cbdataFree(srv);
74addf6c	225	}
	226
	227	static void
	228	helperHandleRead(int fd, void *data)
	229	{
	230	int len;
	231	char *t = NULL;
	232	helper_server *srv = data;
	233	helper_request *r;
	234	helper *hlp = srv->parent;
	235	assert(fd == srv->rfd);
	236	assert(cbdataValid(data));
	237	Counter.syscalls.sock.reads++;
	238	len = read(fd, srv->buf + srv->offset, srv->buf_sz - srv->offset);
	239	fd_bytes(fd, len, FD_READ);
	240	debug(29, 5) ("helperHandleRead: %d bytes from %s #%d.\n",
	241	len, hlp->id_name, srv->index + 1);
	242	if (len <= 0) {
	243	if (len < 0)
	244	debug(50, 1) ("helperHandleRead: FD %d read: %s\n", fd, xstrerror());
	245	comm_close(fd);
	246	return;
	247	}
	248	srv->offset += len;
	249	srv->buf[srv->offset] = '\0';
	250	r = srv->request;
	251	if (r == NULL) {
	252	/* someone spoke without being spoken to */
	253	debug(29, 1) ("helperHandleRead: unexpected read from %s #%d, %d bytes\n",
	254	hlp->id_name, srv->index + 1, len);
	255	srv->offset = 0;
	256	} else if ((t = strchr(srv->buf, '\n'))) {
	257	/* end of reply found */
	258	debug(29, 3) ("helperHandleRead: end of reply found\n");
	259	*t = '\0';
	260	if (cbdataValid(r->data))
	261	r->callback(r->data, srv->buf);
	262	srv->flags.busy = 0;
	263	srv->offset = 0;
	264	helperRequestFree(r);
	265	hlp->stats.replies++;
	266	hlp->stats.avg_svc_time =
	267	intAverage(hlp->stats.avg_svc_time,
	268	tvSubMsec(srv->dispatch_time, current_time),
	269	hlp->stats.replies, REDIRECT_AV_FACTOR);
	270	if (srv->flags.shutdown)
	271	comm_close(srv->wfd);
	272	} else {
	273	commSetSelect(srv->rfd, COMM_SELECT_READ, helperHandleRead, srv, 0);
	274	}
	275	helperKickQueue(hlp);
	276	}
	277
	278	static void
	279	Enqueue(helper * hlp, helper_request * r)
	280	{
	281	dlink_node link = xcalloc(1, sizeof(link));
	282	dlinkAddTail(r, link, &hlp->queue);
	283	hlp->stats.queue_size++;
	284	if (hlp->stats.queue_size < hlp->n_running)
	285	return;
	286	if (squid_curtime - hlp->last_queue_warn < 600)
	287	return;
fe73896c	288	if (shutting_down \|\| reconfiguring)
fe73896c	289	return;
74addf6c	290	hlp->last_queue_warn = squid_curtime;
	291	debug(14, 0) ("WARNING: All %s processes are busy.\n", hlp->id_name);
	292	debug(14, 0) ("WARNING: %d pending requests queued\n", hlp->stats.queue_size);
	293	if (hlp->stats.queue_size > hlp->n_running * 2)
	294	fatalf("Too many queued %s requests", hlp->id_name);
	295	debug(14, 1) ("Consider increasing the number of %s processes in your config file.\n", hlp->id_name);
	296	}
	297
	298	static helper_request *
	299	Dequeue(helper * hlp)
	300	{
	301	dlink_node *link;
	302	helper_request *r = NULL;
	303	if ((link = hlp->queue.head)) {
	304	r = link->data;
	305	dlinkDelete(link, &hlp->queue);
	306	safe_free(link);
	307	hlp->stats.queue_size--;
	308	}
	309	return r;
	310	}
	311
	312	static helper_server *
	313	GetFirstAvailable(helper * hlp)
	314	{
	315	dlink_node *n;
	316	helper_server *srv = NULL;
fe73896c	317	if (hlp->n_running == 0)
fe73896c	318	return NULL;
74addf6c	319	for (n = hlp->servers.head; n != NULL; n = n->next) {
	320	srv = n->data;
	321	if (srv->flags.busy)
	322	continue;
	323	if (!srv->flags.alive)
	324	continue;
	325	return srv;
	326	}
	327	return NULL;
	328	}
	329
	330	static void
	331	helperDispatch(helper_server * srv, helper_request * r)
	332	{
	333	helper *hlp = srv->parent;
	334	if (!cbdataValid(r->data)) {
	335	debug(29, 1) ("helperDispatch: invalid callback data\n");
	336	helperRequestFree(r);
	337	return;
	338	}
	339	assert(!srv->flags.busy);
	340	srv->flags.busy = 1;
	341	srv->request = r;
	342	srv->dispatch_time = current_time;
	343	comm_write(srv->wfd,
	344	r->buf,
	345	strlen(r->buf),
	346	NULL, /* Handler */
	347	NULL, /* Handler-data */
	348	NULL); /* free */
	349	commSetSelect(srv->rfd,
	350	COMM_SELECT_READ,
	351	helperHandleRead,
	352	srv, 0);
	353	debug(29, 5) ("helperDispatch: Request sent to %s #%d, %d bytes\n",
	354	hlp->id_name, srv->index + 1, strlen(r->buf));
	355	srv->stats.uses++;
	356	hlp->stats.requests++;
	357	}
	358
	359	static void
	360	helperKickQueue(helper * hlp)
	361	{
	362	helper_request *r;
	363	helper_server *srv;
	364	while ((srv = GetFirstAvailable(hlp)) && (r = Dequeue(hlp)))
	365	helperDispatch(srv, r);
	366	}
	367
	368	static void
	369	helperRequestFree(helper_request * r)
	370	{
	371	cbdataUnlock(r->data);
	372	xfree(r->buf);
	373	xfree(r);
	374	}