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