common/cli_simple.c

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