xref: /openbmc/obmc-console/console-server.h (revision 4dfefa97)
1 /**
2  * Copyright © 2016 IBM Corporation
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *     http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #pragma once
18 
19 #include <poll.h>
20 #include <stdbool.h>
21 #include <stdint.h>
22 #include <termios.h> /* for speed_t */
23 #include <time.h>
24 #include <systemd/sd-bus.h>
25 #include <sys/time.h>
26 #include <sys/un.h>
27 
28 struct console;
29 struct config;
30 
31 /* Handler API.
32  *
33  * Console data handlers: these implement the functions that process
34  * data coming out of the main tty device.
35  *
36  * Handlers are registered at link time using the console_handler_register()
37  * macro. We call each handler's ->init() function at startup, and ->fini() at
38  * exit.
39  *
40  * Handlers will almost always want to register a ringbuffer consumer, which
41  * provides data coming from the tty. Use cosole_register_ringbuffer_consumer()
42  * for this. To send data to the tty, use console_data_out().
43  *
44  * If a handler needs to monitor a separate file descriptor for events, use the
45  * poller API, through console_poller_register().
46  */
47 struct handler {
48 	const char *name;
49 	int (*init)(struct handler *handler, struct console *console,
50 		    struct config *config);
51 	void (*fini)(struct handler *handler);
52 	int (*baudrate)(struct handler *handler, speed_t baudrate);
53 	bool active;
54 };
55 
56 /* NOLINTBEGIN(bugprone-reserved-identifier,cert-dcl37-c,cert-dcl51-cpp) */
57 #define __handler_name(n) __handler_##n
58 #define _handler_name(n)  __handler_name(n)
59 
60 #define console_handler_register(h)                                            \
61 	static const __attribute__((section("handlers")))                      \
62 	__attribute__((used)) struct handler *                                 \
63 	_handler_name(__COUNTER__) = h
64 /* NOLINTEND(bugprone-reserved-identifier,cert-dcl37-c,cert-dcl51-cpp) */
65 
66 int console_data_out(struct console *console, const uint8_t *data, size_t len);
67 
68 enum poller_ret {
69 	POLLER_OK = 0,
70 	POLLER_REMOVE,
71 	POLLER_EXIT,
72 };
73 
74 typedef char(socket_path_t)[sizeof(((struct sockaddr_un *)NULL)->sun_path)];
75 
76 typedef enum poller_ret (*poller_event_fn_t)(struct handler *handler,
77 					     int revents, void *data);
78 typedef enum poller_ret (*poller_timeout_fn_t)(struct handler *handler,
79 					       void *data);
80 
81 /* Console server structure */
82 struct console {
83 	const char *tty_kname;
84 	char *tty_sysfs_devnode;
85 	char *tty_dev;
86 	const char *console_id;
87 	int tty_sirq;
88 	uint16_t tty_lpc_addr;
89 	speed_t tty_baud;
90 	int tty_fd;
91 
92 	/* Socket name starts with null character hence we need length */
93 	socket_path_t socket_name;
94 	ssize_t socket_name_len;
95 
96 	struct ringbuffer *rb;
97 
98 	struct handler **handlers;
99 	long n_handlers;
100 
101 	struct poller **pollers;
102 	long n_pollers;
103 
104 	struct pollfd *pollfds;
105 	struct sd_bus *bus;
106 };
107 
108 /* poller API */
109 struct poller {
110 	struct handler *handler;
111 	void *data;
112 	poller_event_fn_t event_fn;
113 	poller_timeout_fn_t timeout_fn;
114 	struct timeval timeout;
115 	bool remove;
116 };
117 
118 /* we have two extra entry in the pollfds array for the VUART tty */
119 enum internal_pollfds {
120 	POLLFD_HOSTTTY = 0,
121 	POLLFD_DBUS = 1,
122 	MAX_INTERNAL_POLLFD = 2,
123 };
124 
125 struct poller *console_poller_register(struct console *console,
126 				       struct handler *handler,
127 				       poller_event_fn_t poller_fn,
128 				       poller_timeout_fn_t timeout_fn, int fd,
129 				       int events, void *data);
130 
131 void console_poller_unregister(struct console *console, struct poller *poller);
132 
133 void console_poller_set_events(struct console *console, struct poller *poller,
134 			       int events);
135 
136 void console_poller_set_timeout(struct console *console, struct poller *poller,
137 				const struct timeval *tv);
138 
139 /* ringbuffer API */
140 
141 enum ringbuffer_poll_ret {
142 	RINGBUFFER_POLL_OK = 0,
143 	RINGBUFFER_POLL_REMOVE,
144 };
145 
146 typedef enum ringbuffer_poll_ret (*ringbuffer_poll_fn_t)(void *data,
147 							 size_t force_len);
148 
149 struct ringbuffer_consumer;
150 
151 struct ringbuffer {
152 	uint8_t *buf;
153 	size_t size;
154 	size_t tail;
155 	struct ringbuffer_consumer **consumers;
156 	int n_consumers;
157 };
158 
159 struct ringbuffer_consumer {
160 	struct ringbuffer *rb;
161 	ringbuffer_poll_fn_t poll_fn;
162 	void *poll_data;
163 	size_t pos;
164 };
165 
166 struct ringbuffer *ringbuffer_init(size_t size);
167 void ringbuffer_fini(struct ringbuffer *rb);
168 
169 struct ringbuffer_consumer *
170 ringbuffer_consumer_register(struct ringbuffer *rb,
171 			     ringbuffer_poll_fn_t poll_fn, void *data);
172 
173 void ringbuffer_consumer_unregister(struct ringbuffer_consumer *rbc);
174 
175 int ringbuffer_queue(struct ringbuffer *rb, uint8_t *data, size_t len);
176 
177 size_t ringbuffer_dequeue_peek(struct ringbuffer_consumer *rbc, size_t offset,
178 			       uint8_t **data);
179 
180 int ringbuffer_dequeue_commit(struct ringbuffer_consumer *rbc, size_t len);
181 
182 size_t ringbuffer_len(struct ringbuffer_consumer *rbc);
183 
184 /* console wrapper around ringbuffer consumer registration */
185 struct ringbuffer_consumer *
186 console_ringbuffer_consumer_register(struct console *console,
187 				     ringbuffer_poll_fn_t poll_fn, void *data);
188 
189 /* Console server API */
190 void tty_init_termios(struct console *console);
191 
192 /* config API */
193 struct config;
194 const char *config_get_value(struct config *config, const char *name);
195 struct config *config_init(const char *filename);
196 void config_fini(struct config *config);
197 
198 int config_parse_baud(speed_t *speed, const char *baud_string);
199 uint32_t parse_baud_to_int(speed_t speed);
200 speed_t parse_int_to_baud(uint32_t baud);
201 int config_parse_logsize(const char *size_str, size_t *size);
202 
203 /* socket paths */
204 ssize_t console_socket_path(socket_path_t path, const char *id);
205 ssize_t console_socket_path_readable(const struct sockaddr_un *addr,
206 				     size_t addrlen, socket_path_t path);
207 
208 /* utils */
209 int write_buf_to_fd(int fd, const uint8_t *buf, size_t len);
210 
211 /* console-dbus API */
212 void dbus_init(struct console *console,
213 	       struct config *config __attribute__((unused)));
214 
215 #define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))
216 
217 #ifndef offsetof
218 #define offsetof(type, member) ((unsigned long)&((type *)NULL)->member)
219 #endif
220 
221 #define container_of(ptr, type, member)                                        \
222 	((type *)((void *)((ptr)-offsetof(type, member))))
223 
224 #define BUILD_ASSERT(c)                                                        \
225 	do {                                                                   \
226 		char __c[(c) ? 1 : -1] __attribute__((unused));                \
227 	} while (0)
228