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 #include <stdbool.h>
  11
  12 #include <rte_string_fns.h>
  13
  14 #include "cmdline_private.h"
  15
  16 #ifdef RTE_LIBRTE_CMDLINE_DEBUG
  17 #define debug_printf printf
  18 #else
  19 #define debug_printf(args...) do {} while(0)
  20 #endif
  21
  22 #define CMDLINE_BUFFER_SIZE 64
  23
  24 /* isblank() needs _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE, so use our
  25  * own. */
  26 static int
  27 isblank2(char c)
  28 {
  29         if (c == ' ' ||
  30             c == '\t' )
  31                 return 1;
  32         return 0;
  33 }
  34
  35 static int
  36 isendofline(char c)
  37 {
  38         if (c == '\n' ||
  39             c == '\r' )
  40                 return 1;
  41         return 0;
  42 }
  43
  44 static int
  45 iscomment(char c)
  46 {
  47         if (c == '#')
  48                 return 1;
  49         return 0;
  50 }
  51
  52 int
  53 cmdline_isendoftoken(char c)
  54 {
  55         if (!c || iscomment(c) || isblank2(c) || isendofline(c))
  56                 return 1;
  57         return 0;
  58 }
  59
  60 int
  61 cmdline_isendofcommand(char c)
  62 {
  63         if (!c || iscomment(c) || isendofline(c))
  64                 return 1;
  65         return 0;
  66 }
  67
  68 static unsigned int
  69 nb_common_chars(const char * s1, const char * s2)
  70 {
  71         unsigned int i=0;
  72
  73         while (*s1==*s2 && *s1) {
  74                 s1++;
  75                 s2++;
  76                 i++;
  77         }
  78         return i;
  79 }
  80
  81 /** Retrieve either static or dynamic token at a given index. */
  82 static cmdline_parse_token_hdr_t *
  83 get_token(cmdline_parse_inst_t *inst, unsigned int index)
  84 {
  85         cmdline_parse_token_hdr_t *token_p;
  86
  87         /* check presence of static tokens first */
  88         if (inst->tokens[0] || !inst->f)
  89                 return inst->tokens[index];
  90         /* generate dynamic token */
  91         token_p = NULL;
  92         inst->f(&token_p, NULL, &inst->tokens[index]);
  93         return token_p;
  94 }
  95
  96 /**
  97  * try to match the buffer with an instruction (only the first
  98  * nb_match_token tokens if != 0). Return 0 if we match all the
  99  * tokens, else the number of matched tokens, else -1.
 100  */
 101 static int
 102 match_inst(cmdline_parse_inst_t *inst, const char *buf,
 103            unsigned int nb_match_token, void *resbuf, unsigned resbuf_size)
 104 {
 105         cmdline_parse_token_hdr_t *token_p = NULL;
 106         unsigned int i=0;
 107         int n = 0;
 108         struct cmdline_token_hdr token_hdr;
 109
 110         if (resbuf != NULL)
 111                 memset(resbuf, 0, resbuf_size);
 112         /* check if we match all tokens of inst */
 113         while (!nb_match_token || i < nb_match_token) {
 114                 token_p = get_token(inst, i);
 115                 if (!token_p)
 116                         break;
 117                 memcpy(&token_hdr, token_p, sizeof(token_hdr));
 118
 119                 debug_printf("TK\n");
 120                 /* skip spaces */
 121                 while (isblank2(*buf)) {
 122                         buf++;
 123                 }
 124
 125                 /* end of buf */
 126                 if ( isendofline(*buf) || iscomment(*buf) )
 127                         break;
 128
 129                 if (resbuf == NULL) {
 130                         n = token_hdr.ops->parse(token_p, buf, NULL, 0);
 131                 } else {
 132                         unsigned rb_sz;
 133
 134                         if (token_hdr.offset > resbuf_size) {
 135                                 printf("Parse error(%s:%d): Token offset(%u) "
 136                                         "exceeds maximum size(%u)\n",
 137                                         __FILE__, __LINE__,
 138                                         token_hdr.offset, resbuf_size);
 139                                 return -ENOBUFS;
 140                         }
 141                         rb_sz = resbuf_size - token_hdr.offset;
 142
 143                         n = token_hdr.ops->parse(token_p, buf, (char *)resbuf +
 144                                 token_hdr.offset, rb_sz);
 145                 }
 146
 147                 if (n < 0)
 148                         break;
 149
 150                 debug_printf("TK parsed (len=%d)\n", n);
 151                 i++;
 152                 buf += n;
 153         }
 154
 155         /* does not match */
 156         if (i==0)
 157                 return -1;
 158
 159         /* in case we want to match a specific num of token */
 160         if (nb_match_token) {
 161                 if (i == nb_match_token) {
 162                         return 0;
 163                 }
 164                 return i;
 165         }
 166
 167         /* we don't match all the tokens */
 168         if (token_p) {
 169                 return i;
 170         }
 171
 172         /* are there are some tokens more */
 173         while (isblank2(*buf)) {
 174                 buf++;
 175         }
 176
 177         /* end of buf */
 178         if ( isendofline(*buf) || iscomment(*buf) )
 179                 return 0;
 180
 181         /* garbage after inst */
 182         return i;
 183 }
 184
 185
 186 static inline int
 187 __cmdline_parse(struct cmdline *cl, const char *buf, bool call_fn)
 188 {
 189         unsigned int inst_num=0;
 190         cmdline_parse_inst_t *inst;
 191         const char *curbuf;
 192         union {
 193                 char buf[CMDLINE_PARSE_RESULT_BUFSIZE];
 194                 long double align; /* strong alignment constraint for buf */
 195         } result, tmp_result;
 196         void (*f)(void *, struct cmdline *, void *) = NULL;
 197         void *data = NULL;
 198         int comment = 0;
 199         int linelen = 0;
 200         int parse_it = 0;
 201         int err = CMDLINE_PARSE_NOMATCH;
 202         int tok;
 203         cmdline_parse_ctx_t *ctx;
 204         char *result_buf = result.buf;
 205
 206         if (!cl || !buf)
 207                 return CMDLINE_PARSE_BAD_ARGS;
 208
 209         ctx = cl->ctx;
 210
 211         /*
 212          * - look if the buffer contains at least one line
 213          * - look if line contains only spaces or comments
 214          * - count line length
 215          */
 216         curbuf = buf;
 217         while (! isendofline(*curbuf)) {
 218                 if ( *curbuf == '\0' ) {
 219                         debug_printf("Incomplete buf (len=%d)\n", linelen);
 220                         return 0;
 221                 }
 222                 if ( iscomment(*curbuf) ) {
 223                         comment = 1;
 224                 }
 225                 if ( ! isblank2(*curbuf) && ! comment) {
 226                         parse_it = 1;
 227                 }
 228                 curbuf++;
 229                 linelen++;
 230         }
 231
 232         /* skip all endofline chars */
 233         while (isendofline(buf[linelen])) {
 234                 linelen++;
 235         }
 236
 237         /* empty line */
 238         if ( parse_it == 0 ) {
 239                 debug_printf("Empty line (len=%d)\n", linelen);
 240                 return linelen;
 241         }
 242
 243         debug_printf("Parse line : len=%d, <%.*s>\n",
 244                      linelen, linelen > 64 ? 64 : linelen, buf);
 245
 246         /* parse it !! */
 247         inst = ctx[inst_num];
 248         while (inst) {
 249                 debug_printf("INST %d\n", inst_num);
 250
 251                 /* fully parsed */
 252                 tok = match_inst(inst, buf, 0, result_buf,
 253                                  CMDLINE_PARSE_RESULT_BUFSIZE);
 254
 255                 if (tok > 0) /* we matched at least one token */
 256                         err = CMDLINE_PARSE_BAD_ARGS;
 257
 258                 else if (!tok) {
 259                         debug_printf("INST fully parsed\n");
 260                         /* skip spaces */
 261                         while (isblank2(*curbuf)) {
 262                                 curbuf++;
 263                         }
 264
 265                         /* if end of buf -> there is no garbage after inst */
 266                         if (isendofline(*curbuf) || iscomment(*curbuf)) {
 267                                 if (!f) {
 268                                         memcpy(&f, &inst->f, sizeof(f));
 269                                         memcpy(&data, &inst->data, sizeof(data));
 270                                         result_buf = tmp_result.buf;
 271                                 }
 272                                 else {
 273                                         /* more than 1 inst matches */
 274                                         err = CMDLINE_PARSE_AMBIGUOUS;
 275                                         f=NULL;
 276                                         debug_printf("Ambiguous cmd\n");
 277                                         break;
 278                                 }
 279                         }
 280                 }
 281
 282                 inst_num ++;
 283                 inst = ctx[inst_num];
 284         }
 285
 286         /* no match */
 287         if (f == NULL) {
 288                 debug_printf("No match err=%d\n", err);
 289                 return err;
 290         }
 291
 292         /* call func if requested */
 293         if (call_fn)
 294                 f(result.buf, cl, data);
 295
 296         return linelen;
 297 }
 298
 299 int
 300 cmdline_parse(struct cmdline *cl, const char *buf)
 301 {
 302         return __cmdline_parse(cl, buf, true);
 303 }
 304
 305 int
 306 cmdline_parse_check(struct cmdline *cl, const char *buf)
 307 {
 308         return __cmdline_parse(cl, buf, false);
 309 }
 310
 311 int
 312 cmdline_complete(struct cmdline *cl, const char *buf, int *state,
 313                  char *dst, unsigned int size)
 314 {
 315         const char *partial_tok = buf;
 316         unsigned int inst_num = 0;
 317         cmdline_parse_inst_t *inst;
 318         cmdline_parse_token_hdr_t *token_p;
 319         struct cmdline_token_hdr token_hdr;
 320         char tmpbuf[CMDLINE_BUFFER_SIZE], comp_buf[CMDLINE_BUFFER_SIZE];
 321         unsigned int partial_tok_len;
 322         int comp_len = -1;
 323         int tmp_len = -1;
 324         int nb_token = 0;
 325         unsigned int i, n;
 326         int l;
 327         unsigned int nb_completable;
 328         unsigned int nb_non_completable;
 329         int local_state = 0;
 330         const char *help_str;
 331         cmdline_parse_ctx_t *ctx;
 332
 333         if (!cl || !buf || !state || !dst)
 334                 return -1;
 335
 336         ctx = cl->ctx;
 337
 338         debug_printf("%s called\n", __func__);
 339         memset(&token_hdr, 0, sizeof(token_hdr));
 340
 341         /* count the number of complete token to parse */
 342         for (i=0 ; buf[i] ; i++) {
 343                 if (!isblank2(buf[i]) && isblank2(buf[i+1]))
 344                         nb_token++;
 345                 if (isblank2(buf[i]) && !isblank2(buf[i+1]))
 346                         partial_tok = buf+i+1;
 347         }
 348         partial_tok_len = strnlen(partial_tok, RDLINE_BUF_SIZE);
 349
 350         /* first call -> do a first pass */
 351         if (*state <= 0) {
 352                 debug_printf("try complete <%s>\n", buf);
 353                 debug_printf("there is %d complete tokens, <%s> is incomplete\n",
 354                              nb_token, partial_tok);
 355
 356                 nb_completable = 0;
 357                 nb_non_completable = 0;
 358
 359                 inst = ctx[inst_num];
 360                 while (inst) {
 361                         /* parse the first tokens of the inst */
 362                         if (nb_token &&
 363                             match_inst(inst, buf, nb_token, NULL, 0))
 364                                 goto next;
 365
 366                         debug_printf("instruction match\n");
 367                         token_p = get_token(inst, nb_token);
 368                         if (token_p)
 369                                 memcpy(&token_hdr, token_p, sizeof(token_hdr));
 370
 371                         /* non completable */
 372                         if (!token_p ||
 373                             !token_hdr.ops->complete_get_nb ||
 374                             !token_hdr.ops->complete_get_elt ||
 375                             (n = token_hdr.ops->complete_get_nb(token_p)) == 0) {
 376                                 nb_non_completable++;
 377                                 goto next;
 378                         }
 379
 380                         debug_printf("%d choices for this token\n", n);
 381                         for (i=0 ; i<n ; i++) {
 382                                 if (token_hdr.ops->complete_get_elt(token_p, i,
 383                                                                     tmpbuf,
 384                                                                     sizeof(tmpbuf)) < 0)
 385                                         continue;
 386
 387                                 /* we have at least room for one char */
 388                                 tmp_len = strnlen(tmpbuf, sizeof(tmpbuf));
 389                                 if (tmp_len < CMDLINE_BUFFER_SIZE - 1) {
 390                                         tmpbuf[tmp_len] = ' ';
 391                                         tmpbuf[tmp_len+1] = 0;
 392                                 }
 393
 394                                 debug_printf("   choice <%s>\n", tmpbuf);
 395
 396                                 /* does the completion match the
 397                                  * beginning of the word ? */
 398                                 if (!strncmp(partial_tok, tmpbuf,
 399                                              partial_tok_len)) {
 400                                         if (comp_len == -1) {
 401                                                 strlcpy(comp_buf,
 402                                                         tmpbuf + partial_tok_len,
 403                                                         sizeof(comp_buf));
 404                                                 comp_len =
 405                                                         strnlen(tmpbuf + partial_tok_len,
 406                                                                         sizeof(tmpbuf) - partial_tok_len);
 407
 408                                         }
 409                                         else {
 410                                                 comp_len =
 411                                                         nb_common_chars(comp_buf,
 412                                                                         tmpbuf+partial_tok_len);
 413                                                 comp_buf[comp_len] = 0;
 414                                         }
 415                                         nb_completable++;
 416                                 }
 417                         }
 418                 next:
 419                         debug_printf("next\n");
 420                         inst_num ++;
 421                         inst = ctx[inst_num];
 422                 }
 423
 424                 debug_printf("total choices %d for this completion\n",
 425                              nb_completable);
 426
 427                 /* no possible completion */
 428                 if (nb_completable == 0 && nb_non_completable == 0)
 429                         return 0;
 430
 431                 /* if multichoice is not required */
 432                 if (*state == 0 && partial_tok_len > 0) {
 433                         /* one or several choices starting with the
 434                            same chars */
 435                         if (comp_len > 0) {
 436                                 if ((unsigned)(comp_len + 1) > size)
 437                                         return 0;
 438
 439                                 strlcpy(dst, comp_buf, size);
 440                                 dst[comp_len] = 0;
 441                                 return 2;
 442                         }
 443                 }
 444         }
 445
 446         /* init state correctly */
 447         if (*state == -1)
 448                 *state = 0;
 449
 450         debug_printf("Multiple choice STATE=%d\n", *state);
 451
 452         inst_num = 0;
 453         inst = ctx[inst_num];
 454         while (inst) {
 455                 /* we need to redo it */
 456                 inst = ctx[inst_num];
 457
 458                 if (nb_token &&
 459                     match_inst(inst, buf, nb_token, NULL, 0))
 460                         goto next2;
 461
 462                 token_p = get_token(inst, nb_token);
 463                 if (token_p)
 464                         memcpy(&token_hdr, token_p, sizeof(token_hdr));
 465
 466                 /* one choice for this token */
 467                 if (!token_p ||
 468                     !token_hdr.ops->complete_get_nb ||
 469                     !token_hdr.ops->complete_get_elt ||
 470                     (n = token_hdr.ops->complete_get_nb(token_p)) == 0) {
 471                         if (local_state < *state) {
 472                                 local_state++;
 473                                 goto next2;
 474                         }
 475                         (*state)++;
 476                         if (token_p && token_hdr.ops->get_help) {
 477                                 token_hdr.ops->get_help(token_p, tmpbuf,
 478                                                         sizeof(tmpbuf));
 479                                 help_str = inst->help_str;
 480                                 if (help_str)
 481                                         snprintf(dst, size, "[%s]: %s", tmpbuf,
 482                                                  help_str);
 483                                 else
 484                                         snprintf(dst, size, "[%s]: No help",
 485                                                  tmpbuf);
 486                         }
 487                         else {
 488                                 snprintf(dst, size, "[RETURN]");
 489                         }
 490                         return 1;
 491                 }
 492
 493                 /* several choices */
 494                 for (i=0 ; i<n ; i++) {
 495                         if (token_hdr.ops->complete_get_elt(token_p, i, tmpbuf,
 496                                                             sizeof(tmpbuf)) < 0)
 497                                 continue;
 498                         /* we have at least room for one char */
 499                         tmp_len = strnlen(tmpbuf, sizeof(tmpbuf));
 500                         if (tmp_len < CMDLINE_BUFFER_SIZE - 1) {
 501                                 tmpbuf[tmp_len] = ' ';
 502                                 tmpbuf[tmp_len + 1] = 0;
 503                         }
 504
 505                         debug_printf("   choice <%s>\n", tmpbuf);
 506
 507                         /* does the completion match the beginning of
 508                          * the word ? */
 509                         if (!strncmp(partial_tok, tmpbuf,
 510                                      partial_tok_len)) {
 511                                 if (local_state < *state) {
 512                                         local_state++;
 513                                         continue;
 514                                 }
 515                                 (*state)++;
 516                                 l=strlcpy(dst, tmpbuf, size);
 517                                 if (l>=0 && token_hdr.ops->get_help) {
 518                                         token_hdr.ops->get_help(token_p, tmpbuf,
 519                                                                 sizeof(tmpbuf));
 520                                         help_str = inst->help_str;
 521                                         if (help_str)
 522                                                 snprintf(dst+l, size-l, "[%s]: %s",
 523                                                          tmpbuf, help_str);
 524                                         else
 525                                                 snprintf(dst+l, size-l,
 526                                                          "[%s]: No help", tmpbuf);
 527                                 }
 528
 529                                 return 1;
 530                         }
 531                 }
 532         next2:
 533                 inst_num ++;
 534                 inst = ctx[inst_num];
 535         }
 536         return 0;
 537 }