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