xref: /openbmc/u-boot/common/cli_simple.c (revision e1bf824dfd6881f6f633238c275bfa1e5d83c433)
1 /*
2  * (C) Copyright 2000
3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4  *
5  * Add to readline cmdline-editing by
6  * (C) Copyright 2005
7  * JinHua Luo, GuangDong Linux Center, <luo.jinhua@gd-linux.com>
8  *
9  * SPDX-License-Identifier:	GPL-2.0+
10  */
11 
12 #include <common.h>
13 #include <cli.h>
14 #include <linux/ctype.h>
15 
16 #define DEBUG_PARSER	0	/* set to 1 to debug */
17 
18 #define debug_parser(fmt, args...)		\
19 	debug_cond(DEBUG_PARSER, fmt, ##args)
20 
21 
22 int cli_simple_parse_line(char *line, char *argv[])
23 {
24 	int nargs = 0;
25 
26 	debug_parser("%s: \"%s\"\n", __func__, line);
27 	while (nargs < CONFIG_SYS_MAXARGS) {
28 		/* skip any white space */
29 		while (isblank(*line))
30 			++line;
31 
32 		if (*line == '\0') {	/* end of line, no more args	*/
33 			argv[nargs] = NULL;
34 			debug_parser("%s: nargs=%d\n", __func__, nargs);
35 			return nargs;
36 		}
37 
38 		argv[nargs++] = line;	/* begin of argument string	*/
39 
40 		/* find end of string */
41 		while (*line && !isblank(*line))
42 			++line;
43 
44 		if (*line == '\0') {	/* end of line, no more args	*/
45 			argv[nargs] = NULL;
46 			debug_parser("parse_line: nargs=%d\n", nargs);
47 			return nargs;
48 		}
49 
50 		*line++ = '\0';		/* terminate current arg	 */
51 	}
52 
53 	printf("** Too many args (max. %d) **\n", CONFIG_SYS_MAXARGS);
54 
55 	debug_parser("%s: nargs=%d\n", __func__, nargs);
56 	return nargs;
57 }
58 
59 static void process_macros(const char *input, char *output)
60 {
61 	char c, prev;
62 	const char *varname_start = NULL;
63 	int inputcnt = strlen(input);
64 	int outputcnt = CONFIG_SYS_CBSIZE;
65 	int state = 0;		/* 0 = waiting for '$'  */
66 
67 	/* 1 = waiting for '(' or '{' */
68 	/* 2 = waiting for ')' or '}' */
69 	/* 3 = waiting for '''  */
70 	char *output_start = output;
71 
72 	debug_parser("[PROCESS_MACROS] INPUT len %zd: \"%s\"\n", strlen(input),
73 		     input);
74 
75 	prev = '\0';		/* previous character   */
76 
77 	while (inputcnt && outputcnt) {
78 		c = *input++;
79 		inputcnt--;
80 
81 		if (state != 3) {
82 			/* remove one level of escape characters */
83 			if ((c == '\\') && (prev != '\\')) {
84 				if (inputcnt-- == 0)
85 					break;
86 				prev = c;
87 				c = *input++;
88 			}
89 		}
90 
91 		switch (state) {
92 		case 0:	/* Waiting for (unescaped) $    */
93 			if ((c == '\'') && (prev != '\\')) {
94 				state = 3;
95 				break;
96 			}
97 			if ((c == '$') && (prev != '\\')) {
98 				state++;
99 			} else {
100 				*(output++) = c;
101 				outputcnt--;
102 			}
103 			break;
104 		case 1:	/* Waiting for (        */
105 			if (c == '(' || c == '{') {
106 				state++;
107 				varname_start = input;
108 			} else {
109 				state = 0;
110 				*(output++) = '$';
111 				outputcnt--;
112 
113 				if (outputcnt) {
114 					*(output++) = c;
115 					outputcnt--;
116 				}
117 			}
118 			break;
119 		case 2:	/* Waiting for )        */
120 			if (c == ')' || c == '}') {
121 				int i;
122 				char envname[CONFIG_SYS_CBSIZE], *envval;
123 				/* Varname # of chars */
124 				int envcnt = input - varname_start - 1;
125 
126 				/* Get the varname */
127 				for (i = 0; i < envcnt; i++)
128 					envname[i] = varname_start[i];
129 				envname[i] = 0;
130 
131 				/* Get its value */
132 				envval = getenv(envname);
133 
134 				/* Copy into the line if it exists */
135 				if (envval != NULL)
136 					while ((*envval) && outputcnt) {
137 						*(output++) = *(envval++);
138 						outputcnt--;
139 					}
140 				/* Look for another '$' */
141 				state = 0;
142 			}
143 			break;
144 		case 3:	/* Waiting for '        */
145 			if ((c == '\'') && (prev != '\\')) {
146 				state = 0;
147 			} else {
148 				*(output++) = c;
149 				outputcnt--;
150 			}
151 			break;
152 		}
153 		prev = c;
154 	}
155 
156 	if (outputcnt)
157 		*output = 0;
158 	else
159 		*(output - 1) = 0;
160 
161 	debug_parser("[PROCESS_MACROS] OUTPUT len %zd: \"%s\"\n",
162 		     strlen(output_start), output_start);
163 }
164 
165  /*
166  * WARNING:
167  *
168  * We must create a temporary copy of the command since the command we get
169  * may be the result from getenv(), which returns a pointer directly to
170  * the environment data, which may change magicly when the command we run
171  * creates or modifies environment variables (like "bootp" does).
172  */
173 int cli_simple_run_command(const char *cmd, int flag)
174 {
175 	char cmdbuf[CONFIG_SYS_CBSIZE];	/* working copy of cmd		*/
176 	char *token;			/* start of token in cmdbuf	*/
177 	char *sep;			/* end of token (separator) in cmdbuf */
178 	char finaltoken[CONFIG_SYS_CBSIZE];
179 	char *str = cmdbuf;
180 	char *argv[CONFIG_SYS_MAXARGS + 1];	/* NULL terminated	*/
181 	int argc, inquotes;
182 	int repeatable = 1;
183 	int rc = 0;
184 
185 	debug_parser("[RUN_COMMAND] cmd[%p]=\"", cmd);
186 	if (DEBUG_PARSER) {
187 		/* use puts - string may be loooong */
188 		puts(cmd ? cmd : "NULL");
189 		puts("\"\n");
190 	}
191 	clear_ctrlc();		/* forget any previous Control C */
192 
193 	if (!cmd || !*cmd)
194 		return -1;	/* empty command */
195 
196 	if (strlen(cmd) >= CONFIG_SYS_CBSIZE) {
197 		puts("## Command too long!\n");
198 		return -1;
199 	}
200 
201 	strcpy(cmdbuf, cmd);
202 
203 	/* Process separators and check for invalid
204 	 * repeatable commands
205 	 */
206 
207 	debug_parser("[PROCESS_SEPARATORS] %s\n", cmd);
208 	while (*str) {
209 		/*
210 		 * Find separator, or string end
211 		 * Allow simple escape of ';' by writing "\;"
212 		 */
213 		for (inquotes = 0, sep = str; *sep; sep++) {
214 			if ((*sep == '\'') &&
215 			    (*(sep - 1) != '\\'))
216 				inquotes = !inquotes;
217 
218 			if (!inquotes &&
219 			    (*sep == ';') &&	/* separator		*/
220 			    (sep != str) &&	/* past string start	*/
221 			    (*(sep - 1) != '\\'))	/* and NOT escaped */
222 				break;
223 		}
224 
225 		/*
226 		 * Limit the token to data between separators
227 		 */
228 		token = str;
229 		if (*sep) {
230 			str = sep + 1;	/* start of command for next pass */
231 			*sep = '\0';
232 		} else {
233 			str = sep;	/* no more commands for next pass */
234 		}
235 		debug_parser("token: \"%s\"\n", token);
236 
237 		/* find macros in this token and replace them */
238 		process_macros(token, finaltoken);
239 
240 		/* Extract arguments */
241 		argc = cli_simple_parse_line(finaltoken, argv);
242 		if (argc == 0) {
243 			rc = -1;	/* no command at all */
244 			continue;
245 		}
246 
247 		if (cmd_process(flag, argc, argv, &repeatable, NULL))
248 			rc = -1;
249 
250 		/* Did the user stop this? */
251 		if (had_ctrlc())
252 			return -1;	/* if stopped then not repeatable */
253 	}
254 
255 	return rc ? rc : repeatable;
256 }
257 
258 void cli_loop(void)
259 {
260 	static char lastcommand[CONFIG_SYS_CBSIZE] = { 0, };
261 
262 	int len;
263 	int flag;
264 	int rc = 1;
265 
266 	for (;;) {
267 #ifdef CONFIG_BOOT_RETRY_TIME
268 		if (rc >= 0) {
269 			/* Saw enough of a valid command to
270 			 * restart the timeout.
271 			 */
272 			reset_cmd_timeout();
273 		}
274 #endif
275 		len = cli_readline(CONFIG_SYS_PROMPT);
276 
277 		flag = 0;	/* assume no special flags for now */
278 		if (len > 0)
279 			strcpy(lastcommand, console_buffer);
280 		else if (len == 0)
281 			flag |= CMD_FLAG_REPEAT;
282 #ifdef CONFIG_BOOT_RETRY_TIME
283 		else if (len == -2) {
284 			/* -2 means timed out, retry autoboot
285 			 */
286 			puts("\nTimed out waiting for command\n");
287 # ifdef CONFIG_RESET_TO_RETRY
288 			/* Reinit board to run initialization code again */
289 			do_reset(NULL, 0, 0, NULL);
290 # else
291 			return;		/* retry autoboot */
292 # endif
293 		}
294 #endif
295 
296 		if (len == -1)
297 			puts("<INTERRUPT>\n");
298 		else
299 			rc = run_command(lastcommand, flag);
300 
301 		if (rc <= 0) {
302 			/* invalid command or not repeatable, forget it */
303 			lastcommand[0] = 0;
304 		}
305 	}
306 }
307 
308 int cli_simple_run_command_list(char *cmd, int flag)
309 {
310 	char *line, *next;
311 	int rcode = 0;
312 
313 	/*
314 	 * Break into individual lines, and execute each line; terminate on
315 	 * error.
316 	 */
317 	next = cmd;
318 	line = cmd;
319 	while (*next) {
320 		if (*next == '\n') {
321 			*next = '\0';
322 			/* run only non-empty commands */
323 			if (*line) {
324 				debug("** exec: \"%s\"\n", line);
325 				if (cli_simple_run_command(line, 0) < 0) {
326 					rcode = 1;
327 					break;
328 				}
329 			}
330 			line = next + 1;
331 		}
332 		++next;
333 	}
334 	if (rcode == 0 && *line)
335 		rcode = (cli_simple_run_command(line, 0) >= 0);
336 
337 	return rcode;
338 }
339