logd: transport log data via the new ubus fd api

this fixes the size limitation patch.

Signed-off-by: John Crispin <blogic@openwrt.org>

2 files changed, 150 insertions, 156 deletions

diff --git a/log/logd.c b/log/logd.c
index eda3a7d..0407f4c 100644
--- a/log/logd.c
+++ b/log/logd.c
@@ -12,20 +12,23 @@
  */
 
 #include <stdio.h>
+#include <unistd.h>
 #include <syslog.h>
 
 #include <linux/types.h>
 
 #include <libubox/uloop.h>
 #include <libubox/blobmsg.h>
+#include <libubox/list.h>
+#include <libubox/ustream.h>
 #include <libubus.h>
 
 #include "syslog.h"
 
 int debug = 0;
-static int notify;
 static struct blob_buf b;
 static struct ubus_auto_conn conn;
+static LIST_HEAD(clients);
 
 static const struct blobmsg_policy read_policy =
 	{ .name = "lines", .type = BLOBMSG_TYPE_INT32 };
@@ -33,15 +36,50 @@ static const struct blobmsg_policy read_policy =
 static const struct blobmsg_policy write_policy =
 	{ .name = "event", .type = BLOBMSG_TYPE_STRING };
 
+struct client {
+	struct list_head list;
+
+	struct ustream_fd s;
+	int fd;
+};
+
+static void
+client_close(struct ustream *s)
+{
+	struct client *cl = container_of(s, struct client, s.stream);
+
+	list_del(&cl->list);
+	ustream_free(s);
+	close(cl->fd);
+	free(cl);
+}
+
+static void
+client_notify_write(struct ustream *s, int bytes)
+{
+	if (s->w.data_bytes < 128 && ustream_read_blocked(s))
+		ustream_set_read_blocked(s, false);
+}
+
+static void client_notify_state(struct ustream *s)
+{
+	if (!s->eof)
+		return;
+
+	if (!s->w.data_bytes)
+		return client_close(s);
+}
+
 static int
 read_log(struct ubus_context *ctx, struct ubus_object *obj,
 		struct ubus_request_data *req, const char *method,
 		struct blob_attr *msg)
 {
+	struct client *cl;
 	struct blob_attr *tb;
 	struct log_head *l;
-	void *lines, *entry;
 	int count = 0;
+	int fds[2];
 
 	if (msg) {
 		blobmsg_parse(&read_policy, 1, &tb, blob_data(msg), blob_len(msg));
@@ -49,24 +87,27 @@ read_log(struct ubus_context *ctx, struct ubus_object *obj,
 			count = blobmsg_get_u32(tb);
 	}
 
-	blob_buf_init(&b, 0);
-	lines = blobmsg_open_array(&b, "lines");
+	pipe(fds);
+	ubus_request_set_fd(ctx, req, fds[0]);
 
+	cl = calloc(1, sizeof(*cl));
+	cl->s.stream.notify_write = client_notify_write;
+	cl->s.stream.notify_state = client_notify_state;
+	cl->fd = fds[1];
+	ustream_fd_init(&cl->s, cl->fd);
+	list_add(&cl->list, &clients);
 	l = log_list(count, NULL);
-
-	while (l) {
-		entry = blobmsg_open_table(&b, NULL);
+	while ((!tb || count) && l) {
+		blob_buf_init(&b, 0);
 		blobmsg_add_string(&b, "msg", l->data);
 		blobmsg_add_u32(&b, "id", l->id);
 		blobmsg_add_u32(&b, "priority", l->priority);
 		blobmsg_add_u32(&b, "source", l->source);
 		blobmsg_add_u64(&b, "time", l->ts.tv_sec);
-		blobmsg_close_table(&b, entry);
 		l = log_list(count, l);
+		if (ustream_write(&cl->s.stream, (void *) b.head, blob_len(b.head) + sizeof(struct blob_attr), false) <= 0)
+			break;
 	}
-	blobmsg_close_table(&b, lines);
-	ubus_send_reply(ctx, req, b.head);
-
 	return 0;
 }
 
@@ -89,12 +130,6 @@ write_log(struct ubus_context *ctx, struct ubus_object *obj,
 	return 0;
 }
 
-static void
-log_subscribe_cb(struct ubus_context *ctx, struct ubus_object *obj)
-{
-	notify = obj->has_subscribers;
-}
-
 static const struct ubus_method log_methods[] = {
 	{ .name = "read", .handler = read_log, .policy = &read_policy, .n_policy = 1 },
 	{ .name = "write", .handler = write_log, .policy = &write_policy, .n_policy = 1 },
@@ -108,26 +143,25 @@ static struct ubus_object log_object = {
 	.type = &log_object_type,
 	.methods = log_methods,
 	.n_methods = ARRAY_SIZE(log_methods),
-	.subscribe_cb = log_subscribe_cb,
 };
 
 void
 ubus_notify_log(struct log_head *l)
 {
-	int ret;
+	struct client *c;
 
-	if (!notify)
+	if (list_empty(&clients))
 		return;
 
-	blob_buf_init(&b, 0);
-	blobmsg_add_u32(&b, "id", l->id);
-	blobmsg_add_u32(&b, "priority", l->priority);
-	blobmsg_add_u32(&b, "source", l->source);
-	blobmsg_add_u64(&b, "time", (((__u64) l->ts.tv_sec) * 1000) + (l->ts.tv_nsec / 1000000));
-
-	ret = ubus_notify(&conn.ctx, &log_object, l->data, b.head, -1);
-	if (ret)
-		fprintf(stderr, "Failed to notify log: %s\n", ubus_strerror(ret));
+	list_for_each_entry(c, &clients, list) {
+		blob_buf_init(&b, 0);
+		blobmsg_add_string(&b, "msg", l->data);
+		blobmsg_add_u32(&b, "id", l->id);
+		blobmsg_add_u32(&b, "priority", l->priority);
+		blobmsg_add_u32(&b, "source", l->source);
+		blobmsg_add_u64(&b, "time", (((__u64) l->ts.tv_sec) * 1000) + (l->ts.tv_nsec / 1000000));
+		ustream_write(&c->s.stream, (void *) b.head, blob_len(b.head) + sizeof(struct blob_attr), false);
+	}
 }
 
 static void
diff --git a/log/logread.c b/log/logread.c
index 8c9fda8..28c9462 100644
--- a/log/logread.c
+++ b/log/logread.c
@@ -25,6 +25,7 @@
 #define SYSLOG_NAMES
 #include <syslog.h>
 
+#include <libubox/ustream.h>
 #include <libubox/blobmsg_json.h>
 #include <libubox/usock.h>
 #include <libubox/uloop.h>
@@ -54,12 +55,11 @@ static const struct blobmsg_policy log_policy[] = {
 	[LOG_TIME] = { .name = "time", .type = BLOBMSG_TYPE_INT64 },
 };
 
-static struct ubus_subscriber log_event;
 static struct uloop_timeout retry;
 static struct uloop_fd sender;
 static const char *log_file, *log_ip, *log_port, *log_prefix, *pid_file, *hostname;
 static int log_type = LOG_STDOUT;
-static int log_size, log_udp;
+static int log_size, log_udp, log_follow = 0;
 
 static const char* getcodetext(int value, CODE *codetable) {
 	CODE *i;
@@ -83,12 +83,6 @@ static void log_handle_reconnect(struct uloop_timeout *timeout)
 	}
 }
 
-static void log_handle_remove(struct ubus_context *ctx, struct ubus_subscriber *s,
-			uint32_t id)
-{
-	fprintf(stderr, "Object %08x went away\n", id);
-}
-
 static void log_handle_fd(struct uloop_fd *u, unsigned int events)
 {
 	if (u->eof) {
@@ -99,9 +93,7 @@ static void log_handle_fd(struct uloop_fd *u, unsigned int events)
 	}
 }
 
-static int log_notify(struct ubus_context *ctx, struct ubus_object *obj,
-			struct ubus_request_data *req, const char *method,
-			struct blob_attr *msg)
+static int log_notify(struct blob_attr *msg)
 {
 	struct blob_attr *tb[__LOG_MAX];
 	struct stat s;
@@ -109,13 +101,13 @@ static int log_notify(struct ubus_context *ctx, struct ubus_object *obj,
 	uint32_t p;
 	char *str;
 	time_t t;
-	char *c;
+	char *c, *m;
 
 	if (sender.fd < 0)
 		return 0;
 
 	blobmsg_parse(log_policy, ARRAY_SIZE(log_policy), tb, blob_data(msg), blob_len(msg));
-	if (!tb[LOG_ID] || !tb[LOG_PRIO] || !tb[LOG_SOURCE] || !tb[LOG_TIME])
+	if (!tb[LOG_ID] || !tb[LOG_PRIO] || !tb[LOG_SOURCE] || !tb[LOG_TIME] || !tb[LOG_MSG])
 		return 1;
 
 	if ((log_type == LOG_FILE) && log_size && (!stat(log_file, &s)) && (s.st_size > log_size)) {
@@ -129,11 +121,12 @@ static int log_notify(struct ubus_context *ctx, struct ubus_object *obj,
 		}
 		sender.fd = open(log_file, O_CREAT | O_WRONLY | O_APPEND, 0600);
 		if (sender.fd < 0) {
-//			fprintf(stderr, "failed to open %s: %s\n", log_file, strerror(errno));
+			fprintf(stderr, "failed to open %s: %s\n", log_file, strerror(errno));
 			exit(-1);
 		}
 	}
 
+	m = blobmsg_get_string(tb[LOG_MSG]);
 	t = blobmsg_get_u64(tb[LOG_TIME]) / 1000;
 	c = ctime(&t);
 	p = blobmsg_get_u32(tb[LOG_PRIO]);
@@ -151,7 +144,7 @@ static int log_notify(struct ubus_context *ctx, struct ubus_object *obj,
 		}
 		if (blobmsg_get_u32(tb[LOG_SOURCE]) == SOURCE_KLOG)
 			strncat(buf, "kernel: ", sizeof(buf));
-		strncat(buf, method, sizeof(buf));
+		strncat(buf, m, sizeof(buf));
 		if (log_udp)
 			err = write(sender.fd, buf, strlen(buf));
 		else
@@ -168,8 +161,7 @@ static int log_notify(struct ubus_context *ctx, struct ubus_object *obj,
 	} else {
 		snprintf(buf, sizeof(buf), "%s %s.%s%s %s\n",
 			c, getcodetext(LOG_FAC(p) << 3, facilitynames), getcodetext(LOG_PRI(p), prioritynames),
-			(blobmsg_get_u32(tb[LOG_SOURCE])) ? ("") : (" kernel:"),
-			method);
+			(blobmsg_get_u32(tb[LOG_SOURCE])) ? ("") : (" kernel:"), m);
 		write(sender.fd, buf, strlen(buf));
 	}
 
@@ -180,104 +172,6 @@ static int log_notify(struct ubus_context *ctx, struct ubus_object *obj,
 	return 0;
 }
 
-static void follow_log(struct ubus_context *ctx, int id)
-{
-	FILE *fp;
-	int ret;
-
-	signal(SIGPIPE, SIG_IGN);
-
-	if (pid_file) {
-		fp = fopen(pid_file, "w+");
-		if (fp) {
-			fprintf(fp, "%d", getpid());
-			fclose(fp);
-		}
-	}
-
-	uloop_init();
-	ubus_add_uloop(ctx);
-
-	log_event.remove_cb = log_handle_remove;
-	log_event.cb = log_notify;
-	ret = ubus_register_subscriber(ctx, &log_event);
-	if (ret)
-		fprintf(stderr, "Failed to add watch handler: %s\n", ubus_strerror(ret));
-
-	ret = ubus_subscribe(ctx, &log_event, id);
-	if (ret)
-		fprintf(stderr, "Failed to add watch handler: %s\n", ubus_strerror(ret));
-
-	if (log_ip && log_port) {
-		openlog("logread", LOG_PID, LOG_DAEMON);
-		log_type = LOG_NET;
-		sender.cb = log_handle_fd;
-		retry.cb = log_handle_reconnect;
-		uloop_timeout_set(&retry, 1000);
-	} else if (log_file) {
-		log_type = LOG_FILE;
-		sender.fd = open(log_file, O_CREAT | O_WRONLY| O_APPEND, 0600);
-		if (sender.fd < 0) {
-			fprintf(stderr, "failed to open %s: %s\n", log_file, strerror(errno));
-			exit(-1);
-		}
-	} else {
-		sender.fd = STDOUT_FILENO;
-	}
-
-	uloop_run();
-	ubus_free(ctx);
-	uloop_done();
-}
-
-enum {
-	READ_LINE,
-	__READ_MAX
-};
-
-
-
-static const struct blobmsg_policy read_policy[] = {
-	[READ_LINE] = { .name = "lines", .type = BLOBMSG_TYPE_ARRAY },
-};
-
-static void read_cb(struct ubus_request *req, int type, struct blob_attr *msg)
-{
-	struct blob_attr *cur;
-	struct blob_attr *_tb[__READ_MAX];
-	time_t t;
-	int rem;
-
-	if (!msg)
-		return;
-
-	blobmsg_parse(read_policy, ARRAY_SIZE(read_policy), _tb, blob_data(msg), blob_len(msg));
-	if (!_tb[READ_LINE])
-		return;
-	blobmsg_for_each_attr(cur, _tb[READ_LINE], rem) {
-		struct blob_attr *tb[__LOG_MAX];
-		uint32_t p;
-		char *c;
-
-		if (blobmsg_type(cur) != BLOBMSG_TYPE_TABLE)
-			continue;
-
-		blobmsg_parse(log_policy, ARRAY_SIZE(log_policy), tb, blobmsg_data(cur), blobmsg_data_len(cur));
-		if (!tb[LOG_MSG] || !tb[LOG_ID] || !tb[LOG_PRIO] || !tb[LOG_SOURCE] || !tb[LOG_TIME])
-			continue;
-
-		t = blobmsg_get_u64(tb[LOG_TIME]);
-		p = blobmsg_get_u32(tb[LOG_PRIO]);
-		c = ctime(&t);
-		c[strlen(c) - 1] = '\0';
-
-		printf("%s %s.%s%s %s\n",
-			c, getcodetext(LOG_FAC(p) << 3, facilitynames), getcodetext(LOG_PRI(p), prioritynames),
-			(blobmsg_get_u32(tb[LOG_SOURCE])) ? ("") : (" kernel:"),
-			blobmsg_get_string(tb[LOG_MSG]));
-	}
-}
-
 static int usage(const char *prog)
 {
 	fprintf(stderr, "Usage: %s [options]\n"
@@ -296,14 +190,45 @@ static int usage(const char *prog)
 	return 1;
 }
 
+static void logread_fd_data_cb(struct ustream *s, int bytes)
+{
+	while (true) {
+		int len;
+		struct blob_attr *a;
+
+		a = (void*) ustream_get_read_buf(s, &len);
+		if (len < sizeof(*a) || len < blob_len(a) + sizeof(*a))
+			break;
+		log_notify(a);
+		ustream_consume(s, blob_len(a) + sizeof(*a));
+	}
+	if (!log_follow)
+		uloop_end();
+}
+
+static void logread_fd_cb(struct ubus_request *req, int fd)
+{
+	static struct ustream_fd test_fd;
+
+	test_fd.stream.notify_read = logread_fd_data_cb;
+	ustream_fd_init(&test_fd, fd);
+}
+
+static void logread_complete_cb(struct ubus_request *req, int ret)
+{
+}
+
 int main(int argc, char **argv)
 {
+	static struct ubus_request req;
 	struct ubus_context *ctx;
 	uint32_t id;
 	const char *ubus_socket = NULL;
-	int ch, ret, subscribe = 0, lines = 0;
+	int ch, ret, lines = 0;
 	static struct blob_buf b;
-	int retry = 5;
+	int tries = 5;
+
+	signal(SIGPIPE, SIG_IGN);
 
 	while ((ch = getopt(argc, argv, "ufcs:l:r:F:p:S:P:h:")) != -1) {
 		switch (ch) {
@@ -327,7 +252,7 @@ int main(int argc, char **argv)
 			log_prefix = optarg;
 			break;
 		case 'f':
-			subscribe = 1;
+			log_follow = 1;
 			break;
 		case 'l':
 			lines = atoi(optarg);
@@ -345,12 +270,14 @@ int main(int argc, char **argv)
 			return usage(*argv);
 		}
 	}
+	uloop_init();
 
 	ctx = ubus_connect(ubus_socket);
 	if (!ctx) {
 		fprintf(stderr, "Failed to connect to ubus\n");
 		return -1;
 	}
+	ubus_add_uloop(ctx);
 
 	/* ugly ugly ugly ... we need a real reconnect logic */
 	do {
@@ -360,16 +287,49 @@ int main(int argc, char **argv)
 			sleep(1);
 			continue;
 		}
-		if (!subscribe || lines) {
-			blob_buf_init(&b, 0);
-			if (lines)
-				blobmsg_add_u32(&b, "lines", lines);
-			ubus_invoke(ctx, id, "read", b.head, read_cb, 0, 3000);
+
+		blob_buf_init(&b, 0);
+		if (lines)
+			blobmsg_add_u32(&b, "lines", lines);
+		else if (log_follow)
+			blobmsg_add_u32(&b, "lines", 0);
+		if (log_follow) {
+			if (pid_file) {
+				FILE *fp = fopen(pid_file, "w+");
+				if (fp) {
+					fprintf(fp, "%d", getpid());
+					fclose(fp);
+				}
+			}
+		}
+
+		if (log_ip && log_port) {
+			openlog("logread", LOG_PID, LOG_DAEMON);
+			log_type = LOG_NET;
+			sender.cb = log_handle_fd;
+			retry.cb = log_handle_reconnect;
+			uloop_timeout_set(&retry, 1000);
+		} else if (log_file) {
+			log_type = LOG_FILE;
+			sender.fd = open(log_file, O_CREAT | O_WRONLY| O_APPEND, 0600);
+			if (sender.fd < 0) {
+				fprintf(stderr, "failed to open %s: %s\n", log_file, strerror(errno));
+				exit(-1);
+			}
+		} else {
+			sender.fd = STDOUT_FILENO;
 		}
 
-		if (subscribe)
-			follow_log(ctx, id);
-	} while (ret && retry--);
+		ubus_invoke_async(ctx, id, "read", b.head, &req);
+		req.fd_cb = logread_fd_cb;
+		req.complete_cb = logread_complete_cb;
+		ubus_complete_request_async(ctx, &req);
 
-	return 0;
+		uloop_run();
+		ubus_free(ctx);
+		uloop_done();
+
+	} while (ret && tries--);
+
+	return ret;
 }