lib/cmdline/cmdline_parse.c

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright(c) 2010-2014 Intel Corporation.
   3  * Copyright (c) 2009, Olivier MATZ <zer0@droids-corp.org>
   4  * All rights reserved.
   5  */
   6
   7 #include <stdio.h>
   8 #include <errno.h>
   9 #include <string.h>
  10
  11 #include <rte_string_fns.h>
  12
  13 #include "cmdline_private.h"
  14
  15 #ifdef RTE_LIBRTE_CMDLINE_DEBUG
  16 #define debug_printf printf
  17 #else
  18 #define debug_printf(args...) do {} while(0)
  19 #endif
  20
  21 #define CMDLINE_BUFFER_SIZE 64
  22
  23 /* isblank() needs _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE, so use our
  24  * own. */
  25 static int
  26 isblank2(char c)
  27 {
  28         if (c == ' ' ||
  29             c == '\t' )
  30                 return 1;
  31         return 0;
  32 }
  33
  34 static int
  35 isendofline(char c)
  36 {
  37         if (c == '\n' ||
  38             c == '\r' )
  39                 return 1;
  40         return 0;
  41 }
  42
  43 static int
  44 iscomment(char c)
  45 {
  46         if (c == '#')
  47                 return 1;
  48         return 0;
  49 }
  50
  51 int
  52 cmdline_isendoftoken(char c)
  53 {
  54         if (!c || iscomment(c) || isblank2(c) || isendofline(c))
  55                 return 1;
  56         return 0;
  57 }
  58
  59 int
  60 cmdline_isendofcommand(char c)
  61 {
  62         if (!c || iscomment(c) || isendofline(c))
  63                 return 1;
  64         return 0;
  65 }
  66
  67 static unsigned int
  68 nb_common_chars(const char * s1, const char * s2)
  69 {
  70         unsigned int i=0;
  71
  72         while (*s1==*s2 && *s1) {
  73                 s1++;
  74                 s2++;
  75                 i++;
  76         }
  77         return i;
  78 }
  79
  80 /** Retrieve either static or dynamic token at a given index. */
  81 static cmdline_parse_token_hdr_t *
  82 get_token(cmdline_parse_inst_t *inst, unsigned int index)
  83 {
  84         cmdline_parse_token_hdr_t *token_p;
  85
  86         /* check presence of static tokens first */
  87         if (inst->tokens[0] || !inst->f)
  88                 return inst->tokens[index];
  89         /* generate dynamic token */
  90         token_p = NULL;
  91         inst->f(&token_p, NULL, &inst->tokens[index]);
  92         return token_p;
  93 }
  94
  95 /**
  96  * try to match the buffer with an instruction (only the first
  97  * nb_match_token tokens if != 0). Return 0 if we match all the
  98  * tokens, else the number of matched tokens, else -1.
  99  */
 100 static int
 101 match_inst(cmdline_parse_inst_t *inst, const char *buf,
 102            unsigned int nb_match_token, void *resbuf, unsigned resbuf_size)
 103 {
 104         cmdline_parse_token_hdr_t *token_p = NULL;
 105         unsigned int i=0;
 106         int n = 0;
 107         struct cmdline_token_hdr token_hdr;
 108
 109         if (resbuf != NULL)
 110                 memset(resbuf, 0, resbuf_size);
 111         /* check if we match all tokens of inst */
 112         while (!nb_match_token || i < nb_match_token) {
 113                 token_p = get_token(inst, i);
 114                 if (!token_p)
 115                         break;
 116                 memcpy(&token_hdr, token_p, sizeof(token_hdr));
 117
 118                 debug_printf("TK\n");
 119                 /* skip spaces */
 120                 while (isblank2(*buf)) {
 121                         buf++;
 122                 }
 123
 124                 /* end of buf */
 125                 if ( isendofline(*buf) || iscomment(*buf) )
 126                         break;
 127
 128                 if (resbuf == NULL) {
 129                         n = token_hdr.ops->parse(token_p, buf, NULL, 0);
 130                 } else {
 131                         unsigned rb_sz;
 132
 133                         if (token_hdr.offset > resbuf_size) {
 134                                 printf("Parse error(%s:%d): Token offset(%u) "
 135                                         "exceeds maximum size(%u)\n",
 136                                         __FILE__, __LINE__,
 137                                         token_hdr.offset, resbuf_size);
 138                                 return -ENOBUFS;
 139                         }
 140                         rb_sz = resbuf_size - token_hdr.offset;
 141
 142                         n = token_hdr.ops->parse(token_p, buf, (char *)resbuf +
 143                                 token_hdr.offset, rb_sz);
 144                 }
 145
 146                 if (n < 0)
 147                         break;
 148
 149                 debug_printf("TK parsed (len=%d)\n", n);
 150                 i++;
 151                 buf += n;
 152         }
 153
 154         /* does not match */
 155         if (i==0)
 156                 return -1;
 157
 158         /* in case we want to match a specific num of token */
 159         if (nb_match_token) {
 160                 if (i == nb_match_token) {
 161                         return 0;
 162                 }
 163                 return i;
 164         }
 165
 166         /* we don't match all the tokens */
 167         if (token_p) {
 168                 return i;
 169         }
 170
 171         /* are there are some tokens more */
 172         while (isblank2(*buf)) {
 173                 buf++;
 174         }
 175
 176         /* end of buf */
 177         if ( isendofline(*buf) || iscomment(*buf) )
 178                 return 0;
 179
 180         /* garbage after inst */
 181         return i;
 182 }
 183
 184
 185 int
 186 cmdline_parse(struct cmdline *cl, const char * buf)
 187 {
 188         unsigned int inst_num=0;
 189         cmdline_parse_inst_t *inst;
 190         const char *curbuf;
 191         union {
 192                 char buf[CMDLINE_PARSE_RESULT_BUFSIZE];
 193                 long double align; /* strong alignment constraint for buf */
 194         } result, tmp_result;
 195         void (*f)(void *, struct cmdline *, void *) = NULL;
 196         void *data = NULL;
 197         int comment = 0;
 198         int linelen = 0;
 199         int parse_it = 0;
 200         int err = CMDLINE_PARSE_NOMATCH;
 201         int tok;
 202         cmdline_parse_ctx_t *ctx;
 203         char *result_buf = result.buf;
 204
 205         if (!cl || !buf)
 206                 return CMDLINE_PARSE_BAD_ARGS;
 207
 208         ctx = cl->ctx;
 209
 210         /*
 211          * - look if the buffer contains at least one line
 212          * - look if line contains only spaces or comments
 213          * - count line length
 214          */
 215         curbuf = buf;
 216         while (! isendofline(*curbuf)) {
 217                 if ( *curbuf == '\0' ) {
 218                         debug_printf("Incomplete buf (len=%d)\n", linelen);
 219                         return 0;
 220                 }
 221                 if ( iscomment(*curbuf) ) {
 222                         comment = 1;
 223                 }
 224                 if ( ! isblank2(*curbuf) && ! comment) {
 225                         parse_it = 1;
 226                 }
 227                 curbuf++;
 228                 linelen++;
 229         }
 230
 231         /* skip all endofline chars */
 232         while (isendofline(buf[linelen])) {
 233                 linelen++;
 234         }
 235
 236         /* empty line */
 237         if ( parse_it == 0 ) {
 238                 debug_printf("Empty line (len=%d)\n", linelen);
 239                 return linelen;
 240         }
 241
 242         debug_printf("Parse line : len=%d, <%.*s>\n",
 243                      linelen, linelen > 64 ? 64 : linelen, buf);
 244
 245         /* parse it !! */
 246         inst = ctx[inst_num];
 247         while (inst) {
 248                 debug_printf("INST %d\n", inst_num);
 249
 250                 /* fully parsed */
 251                 tok = match_inst(inst, buf, 0, result_buf,
 252                                  CMDLINE_PARSE_RESULT_BUFSIZE);
 253
 254                 if (tok > 0) /* we matched at least one token */
 255                         err = CMDLINE_PARSE_BAD_ARGS;
 256
 257                 else if (!tok) {
 258                         debug_printf("INST fully parsed\n");
 259                         /* skip spaces */
 260                         while (isblank2(*curbuf)) {
 261                                 curbuf++;
 262                         }
 263
 264                         /* if end of buf -> there is no garbage after inst */
 265                         if (isendofline(*curbuf) || iscomment(*curbuf)) {
 266                                 if (!f) {
 267                                         memcpy(&f, &inst->f, sizeof(f));
 268                                         memcpy(&data, &inst->data, sizeof(data));
 269                                         result_buf = tmp_result.buf;
 270                                 }
 271                                 else {
 272                                         /* more than 1 inst matches */
 273                                         err = CMDLINE_PARSE_AMBIGUOUS;
 274                                         f=NULL;
 275                                         debug_printf("Ambiguous cmd\n");
 276                                         break;
 277                                 }
 278                         }
 279                 }
 280
 281                 inst_num ++;
 282                 inst = ctx[inst_num];
 283         }
 284
 285         /* call func */
 286         if (f) {
 287                 f(result.buf, cl, data);
 288         }
 289
 290         /* no match */
 291         else {
 292                 debug_printf("No match err=%d\n", err);
 293                 return err;
 294         }
 295
 296         return linelen;
 297 }
 298
 299 int
 300 cmdline_complete(struct cmdline *cl, const char *buf, int *state,
 301                  char *dst, unsigned int size)
 302 {
 303         const char *partial_tok = buf;
 304         unsigned int inst_num = 0;
 305         cmdline_parse_inst_t *inst;
 306         cmdline_parse_token_hdr_t *token_p;
 307         struct cmdline_token_hdr token_hdr;
 308         char tmpbuf[CMDLINE_BUFFER_SIZE], comp_buf[CMDLINE_BUFFER_SIZE];
 309         unsigned int partial_tok_len;
 310         int comp_len = -1;
 311         int tmp_len = -1;
 312         int nb_token = 0;
 313         unsigned int i, n;
 314         int l;
 315         unsigned int nb_completable;
 316         unsigned int nb_non_completable;
 317         int local_state = 0;
 318         const char *help_str;
 319         cmdline_parse_ctx_t *ctx;
 320
 321         if (!cl || !buf || !state || !dst)
 322                 return -1;
 323
 324         ctx = cl->ctx;
 325
 326         debug_printf("%s called\n", __func__);
 327         memset(&token_hdr, 0, sizeof(token_hdr));
 328
 329         /* count the number of complete token to parse */
 330         for (i=0 ; buf[i] ; i++) {
 331                 if (!isblank2(buf[i]) && isblank2(buf[i+1]))
 332                         nb_token++;
 333                 if (isblank2(buf[i]) && !isblank2(buf[i+1]))
 334                         partial_tok = buf+i+1;
 335         }
 336         partial_tok_len = strnlen(partial_tok, RDLINE_BUF_SIZE);
 337
 338         /* first call -> do a first pass */
 339         if (*state <= 0) {
 340                 debug_printf("try complete <%s>\n", buf);
 341                 debug_printf("there is %d complete tokens, <%s> is incomplete\n",
 342                              nb_token, partial_tok);
 343
 344                 nb_completable = 0;
 345                 nb_non_completable = 0;
 346
 347                 inst = ctx[inst_num];
 348                 while (inst) {
 349                         /* parse the first tokens of the inst */
 350                         if (nb_token &&
 351                             match_inst(inst, buf, nb_token, NULL, 0))
 352                                 goto next;
 353
 354                         debug_printf("instruction match\n");
 355                         token_p = get_token(inst, nb_token);
 356                         if (token_p)
 357                                 memcpy(&token_hdr, token_p, sizeof(token_hdr));
 358
 359                         /* non completable */
 360                         if (!token_p ||
 361                             !token_hdr.ops->complete_get_nb ||
 362                             !token_hdr.ops->complete_get_elt ||
 363                             (n = token_hdr.ops->complete_get_nb(token_p)) == 0) {
 364                                 nb_non_completable++;
 365                                 goto next;
 366                         }
 367
 368                         debug_printf("%d choices for this token\n", n);
 369                         for (i=0 ; i<n ; i++) {
 370                                 if (token_hdr.ops->complete_get_elt(token_p, i,
 371                                                                     tmpbuf,
 372                                                                     sizeof(tmpbuf)) < 0)
 373                                         continue;
 374
 375                                 /* we have at least room for one char */
 376                                 tmp_len = strnlen(tmpbuf, sizeof(tmpbuf));
 377                                 if (tmp_len < CMDLINE_BUFFER_SIZE - 1) {
 378                                         tmpbuf[tmp_len] = ' ';
 379                                         tmpbuf[tmp_len+1] = 0;
 380                                 }
 381
 382                                 debug_printf("   choice <%s>\n", tmpbuf);
 383
 384                                 /* does the completion match the
 385                                  * beginning of the word ? */
 386                                 if (!strncmp(partial_tok, tmpbuf,
 387                                              partial_tok_len)) {
 388                                         if (comp_len == -1) {
 389                                                 strlcpy(comp_buf,
 390                                                         tmpbuf + partial_tok_len,
 391                                                         sizeof(comp_buf));
 392                                                 comp_len =
 393                                                         strnlen(tmpbuf + partial_tok_len,
 394                                                                         sizeof(tmpbuf) - partial_tok_len);
 395
 396                                         }
 397                                         else {
 398                                                 comp_len =
 399                                                         nb_common_chars(comp_buf,
 400                                                                         tmpbuf+partial_tok_len);
 401                                                 comp_buf[comp_len] = 0;
 402                                         }
 403                                         nb_completable++;
 404                                 }
 405                         }
 406                 next:
 407                         debug_printf("next\n");
 408                         inst_num ++;
 409                         inst = ctx[inst_num];
 410                 }
 411
 412                 debug_printf("total choices %d for this completion\n",
 413                              nb_completable);
 414
 415                 /* no possible completion */
 416                 if (nb_completable == 0 && nb_non_completable == 0)
 417                         return 0;
 418
 419                 /* if multichoice is not required */
 420                 if (*state == 0 && partial_tok_len > 0) {
 421                         /* one or several choices starting with the
 422                            same chars */
 423                         if (comp_len > 0) {
 424                                 if ((unsigned)(comp_len + 1) > size)
 425                                         return 0;
 426
 427                                 strlcpy(dst, comp_buf, size);
 428                                 dst[comp_len] = 0;
 429                                 return 2;
 430                         }
 431                 }
 432         }
 433
 434         /* init state correctly */
 435         if (*state == -1)
 436                 *state = 0;
 437
 438         debug_printf("Multiple choice STATE=%d\n", *state);
 439
 440         inst_num = 0;
 441         inst = ctx[inst_num];
 442         while (inst) {
 443                 /* we need to redo it */
 444                 inst = ctx[inst_num];
 445
 446                 if (nb_token &&
 447                     match_inst(inst, buf, nb_token, NULL, 0))
 448                         goto next2;
 449
 450                 token_p = get_token(inst, nb_token);
 451                 if (token_p)
 452                         memcpy(&token_hdr, token_p, sizeof(token_hdr));
 453
 454                 /* one choice for this token */
 455                 if (!token_p ||
 456                     !token_hdr.ops->complete_get_nb ||
 457                     !token_hdr.ops->complete_get_elt ||
 458                     (n = token_hdr.ops->complete_get_nb(token_p)) == 0) {
 459                         if (local_state < *state) {
 460                                 local_state++;
 461                                 goto next2;
 462                         }
 463                         (*state)++;
 464                         if (token_p && token_hdr.ops->get_help) {
 465                                 token_hdr.ops->get_help(token_p, tmpbuf,
 466                                                         sizeof(tmpbuf));
 467                                 help_str = inst->help_str;
 468                                 if (help_str)
 469                                         snprintf(dst, size, "[%s]: %s", tmpbuf,
 470                                                  help_str);
 471                                 else
 472                                         snprintf(dst, size, "[%s]: No help",
 473                                                  tmpbuf);
 474                         }
 475                         else {
 476                                 snprintf(dst, size, "[RETURN]");
 477                         }
 478                         return 1;
 479                 }
 480
 481                 /* several choices */
 482                 for (i=0 ; i<n ; i++) {
 483                         if (token_hdr.ops->complete_get_elt(token_p, i, tmpbuf,
 484                                                             sizeof(tmpbuf)) < 0)
 485                                 continue;
 486                         /* we have at least room for one char */
 487                         tmp_len = strnlen(tmpbuf, sizeof(tmpbuf));
 488                         if (tmp_len < CMDLINE_BUFFER_SIZE - 1) {
 489                                 tmpbuf[tmp_len] = ' ';
 490                                 tmpbuf[tmp_len + 1] = 0;
 491                         }
 492
 493                         debug_printf("   choice <%s>\n", tmpbuf);
 494
 495                         /* does the completion match the beginning of
 496                          * the word ? */
 497                         if (!strncmp(partial_tok, tmpbuf,
 498                                      partial_tok_len)) {
 499                                 if (local_state < *state) {
 500                                         local_state++;
 501                                         continue;
 502                                 }
 503                                 (*state)++;
 504                                 l=strlcpy(dst, tmpbuf, size);
 505                                 if (l>=0 && token_hdr.ops->get_help) {
 506                                         token_hdr.ops->get_help(token_p, tmpbuf,
 507                                                                 sizeof(tmpbuf));
 508                                         help_str = inst->help_str;
 509                                         if (help_str)
 510                                                 snprintf(dst+l, size-l, "[%s]: %s",
 511                                                          tmpbuf, help_str);
 512                                         else
 513                                                 snprintf(dst+l, size-l,
 514                                                          "[%s]: No help", tmpbuf);
 515                                 }
 516
 517                                 return 1;
 518                         }
 519                 }
 520         next2:
 521                 inst_num ++;
 522                 inst = ctx[inst_num];
 523         }
 524         return 0;
 525 }