1/* SPDX-License-Identifier: GPL-2.0+ */
2/*
3 * (C) Copyright 2014 Google, Inc
4 * Simon Glass <sjg@chromium.org>
5 */
6
7#ifndef __CLI_H
8#define __CLI_H
9
10#include <stdbool.h>
11#include <linux/types.h>
12
13/**
14 * struct cli_ch_state - state information for reading cmdline characters
15 *
16 * @esc_len: Number of escape characters read so far
17 * @esc_save: Escape characters collected so far
18 * @emit_upto: Next index to emit from esc_save
19 * @emitting: true if emitting from esc_save
20 */
21struct cli_ch_state {
22	int esc_len;
23	char esc_save[8];
24	int emit_upto;
25	bool emitting;
26};
27
28/**
29 * struct cli_line_state - state of the line editor
30 *
31 * @num: Current cursor position, where 0 is the start
32 * @eol_num: Number of characters in the buffer
33 * @insert: true if in 'insert' mode
34 * @history: true if history should be accessible
35 * @cmd_complete: true if tab completion should be enabled (requires @prompt to
36 *	be set)
37 * @buf: Buffer containing line
38 * @prompt: Prompt for the line
39 */
40struct cli_line_state {
41	uint num;
42	uint eol_num;
43	uint len;
44	bool insert;
45	bool history;
46	bool cmd_complete;
47	char *buf;
48	const char *prompt;
49};
50
51/**
52 * Go into the command loop
53 *
54 * This will return if we get a timeout waiting for a command. See
55 * CONFIG_BOOT_RETRY_TIME.
56 */
57void cli_simple_loop(void);
58
59/**
60 * cli_simple_run_command() - Execute a command with the simple CLI
61 *
62 * @cmd:	String containing the command to execute
63 * @flag	Flag value - see CMD_FLAG_...
64 * Return: 1  - command executed, repeatable
65 *	0  - command executed but not repeatable, interrupted commands are
66 *	     always considered not repeatable
67 *	-1 - not executed (unrecognized, bootd recursion or too many args)
68 *           (If cmd is NULL or "" or longer than CONFIG_SYS_CBSIZE-1 it is
69 *           considered unrecognized)
70 */
71int cli_simple_run_command(const char *cmd, int flag);
72
73/**
74 * cli_simple_process_macros() - Expand $() and ${} format env. variables
75 *
76 * @param input		Input string possible containing $() / ${} vars
77 * @param output	Output string with $() / ${} vars expanded
78 * @param max_size	Maximum size of @output (including terminator)
79 * Return: 0 if OK, -ENOSPC if we ran out of space in @output
80 */
81int cli_simple_process_macros(const char *input, char *output, int max_size);
82
83/**
84 * cli_simple_run_command_list() - Execute a list of command
85 *
86 * The commands should be separated by ; or \n and will be executed
87 * by the built-in parser.
88 *
89 * This function cannot take a const char * for the command, since if it
90 * finds newlines in the string, it replaces them with \0.
91 *
92 * @param cmd	String containing list of commands
93 * @param flag	Execution flags (CMD_FLAG_...)
94 * Return: 0 on success, or != 0 on error.
95 */
96int cli_simple_run_command_list(char *cmd, int flag);
97
98/**
99 * cli_readline() - read a line into the console_buffer
100 *
101 * This is a convenience function which calls cli_readline_into_buffer().
102 *
103 * @prompt: Prompt to display
104 * Return: command line length excluding terminator, or -ve on error
105 */
106int cli_readline(const char *const prompt);
107
108/**
109 * readline_into_buffer() - read a line into a buffer
110 *
111 * Display the prompt, then read a command line into @buffer. The
112 * maximum line length is CONFIG_SYS_CBSIZE including a \0 terminator, which
113 * will always be added.
114 *
115 * The command is echoed as it is typed. Command editing is supported if
116 * CONFIG_CMDLINE_EDITING is defined. Tab auto-complete is supported if
117 * CONFIG_AUTO_COMPLETE is defined. If CONFIG_BOOT_RETRY_TIME is defined,
118 * then a timeout will be applied.
119 *
120 * If CONFIG_BOOT_RETRY_TIME is defined and retry_time >= 0,
121 * time out when time goes past endtime (timebase time in ticks).
122 *
123 * @prompt:	Prompt to display
124 * @buffer:	Place to put the line that is entered
125 * @timeout:	Timeout in seconds, 0 if none
126 * Return: command line length excluding terminator, or -ve on error: if the
127 * timeout is exceeded (either CONFIG_BOOT_RETRY_TIME or the timeout
128 * parameter), then -2 is returned. If a break is detected (Ctrl-C) then
129 * -1 is returned.
130 */
131int cli_readline_into_buffer(const char *const prompt, char *buffer,
132				int timeout);
133
134/**
135 * parse_line() - split a command line down into separate arguments
136 *
137 * The argv[] array is filled with pointers into @line, and each argument
138 * is terminated by \0 (i.e. @line is changed in the process unless there
139 * is only one argument).
140 *
141 * #argv is terminated by a NULL after the last argument pointer.
142 *
143 * At most CONFIG_SYS_MAXARGS arguments are permited - if there are more
144 * than that then an error is printed, and this function returns
145 * CONFIG_SYS_MAXARGS, with argv[] set up to that point.
146 *
147 * @line:	Command line to parse
148 * @args:	Array to hold arguments
149 * Return: number of arguments
150 */
151int cli_simple_parse_line(char *line, char *argv[]);
152
153#if CONFIG_IS_ENABLED(OF_CONTROL)
154/**
155 * cli_process_fdt() - process the boot command from the FDT
156 *
157 * If bootcmmd is defined in the /config node of the FDT, we use that
158 * as the boot command. Further, if bootsecure is set to 1 (in the same
159 * node) then we return true, indicating that the command should be executed
160 * as securely as possible, avoiding the CLI parser.
161 *
162 * @cmdp:	On entry, the command that will be executed if the FDT does
163 *		not have a command. Returns the command to execute after
164 *		checking the FDT.
165 * Return: true to execute securely, else false
166 */
167bool cli_process_fdt(const char **cmdp);
168
169/** cli_secure_boot_cmd() - execute a command as securely as possible
170 *
171 * This avoids using the parser, thus executing the command with the
172 * smallest amount of code. Parameters are not supported.
173 */
174void cli_secure_boot_cmd(const char *cmd);
175#else
176static inline bool cli_process_fdt(const char **cmdp)
177{
178	return false;
179}
180
181static inline void cli_secure_boot_cmd(const char *cmd)
182{
183}
184#endif /* CONFIG_OF_CONTROL */
185
186/**
187 * Go into the command loop
188 *
189 * This will return if we get a timeout waiting for a command, but only for
190 * the simple parser (not hush). See CONFIG_BOOT_RETRY_TIME.
191 */
192void cli_loop(void);
193
194/** Set up the command line interpreter ready for action */
195void cli_init(void);
196
197#define endtick(seconds) (get_ticks() + (uint64_t)(seconds) * get_tbclk())
198#define CTL_CH(c)		((c) - 'a' + 1)
199
200/**
201 * cli_ch_init() - Set up the initial state to process input characters
202 *
203 * @cch: State to set up
204 */
205void cli_ch_init(struct cli_ch_state *cch);
206
207/**
208 * cli_ch_process() - Process an input character
209 *
210 * When @ichar is 0, this function returns any characters from an invalid escape
211 * sequence which are still pending in the buffer
212 *
213 * Otherwise it processes the input character. If it is an escape character,
214 * then an escape sequence is started and the function returns 0. If we are in
215 * the middle of an escape sequence, the character is processed and may result
216 * in returning 0 (if more characters are needed) or a valid character (if
217 * @ichar finishes the sequence).
218 *
219 * If @ichar is a valid character and there is no escape sequence in progress,
220 * then it is returned as is.
221 *
222 * If the Enter key is pressed, '\n' is returned.
223 *
224 * Usage should be like this::
225 *
226 *    struct cli_ch_state cch;
227 *
228 *    cli_ch_init(cch);
229 *    do
230 *       {
231 *       int ichar, ch;
232 *
233 *       ichar = cli_ch_process(cch, 0);
234 *       if (!ichar) {
235 *          ch = getchar();
236 *          ichar = cli_ch_process(cch, ch);
237 *       }
238 *       (handle the ichar character)
239 *    } while (!done)
240 *
241 * If tstc() is used to look for keypresses, this function can be called with
242 * @ichar set to -ETIMEDOUT if there is no character after 5-10ms. This allows
243 * the ambgiuity between the Escape key and the arrow keys (which generate an
244 * escape character followed by other characters) to be resolved.
245 *
246 * @cch: Current state
247 * @ichar: Input character to process, or 0 if none, or -ETIMEDOUT if no
248 * character has been received within a small number of milliseconds (this
249 * cancels any existing escape sequence and allows pressing the Escape key to
250 * work)
251 * Returns: Resulting input character after processing, 0 if none, '\e' if
252 * an existing escape sequence was cancelled
253 */
254int cli_ch_process(struct cli_ch_state *cch, int ichar);
255
256/**
257 * cread_line_process_ch() - Process a character for line input
258 *
259 * @cls: CLI line state
260 * @ichar: Character to process
261 * Return: 0 if input is complete, with line in cls->buf, -EINTR if input was
262 * cancelled with Ctrl-C, -EAGAIN if more characters are needed
263 */
264int cread_line_process_ch(struct cli_line_state *cls, char ichar);
265
266/**
267 * cli_cread_init() - Set up a new cread struct
268 *
269 * Sets up a new cread state, with history and cmd_complete set to false
270 *
271 * After calling this, you can use cread_line_process_ch() to process characters
272 * received from the user.
273 *
274 * @cls: CLI line state
275 * @buf: Text buffer containing the initial text
276 * @buf_size: Buffer size, including nul terminator
277 */
278void cli_cread_init(struct cli_line_state *cls, char *buf, uint buf_size);
279
280/** cread_print_hist_list() - Print the command-line history list */
281void cread_print_hist_list(void);
282
283#endif
284