src/lib/cmdline_parse.c

   1 /*
   2  * Copyright (c) 2009, Olivier MATZ <zer0@droids-corp.org>
   3  * All rights reserved.
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions are met:
   6  *
   7  *     * Redistributions of source code must retain the above copyright
   8  *       notice, this list of conditions and the following disclaimer.
   9  *     * Redistributions in binary form must reproduce the above copyright
  10  *       notice, this list of conditions and the following disclaimer in the
  11  *       documentation and/or other materials provided with the distribution.
  12  *     * Neither the name of the University of California, Berkeley nor the
  13  *       names of its contributors may be used to endorse or promote products
  14  *       derived from this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND ANY
  17  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  18  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  19  * DISCLAIMED. IN NO EVENT SHALL THE REGENTS AND CONTRIBUTORS BE LIABLE FOR ANY
  20  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  21  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  22  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  23  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  25  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  */
  27
  28 #include <stdio.h>
  29 #include <string.h>
  30 #include <inttypes.h>
  31 #include <ctype.h>
  32
  33 #include <netinet/in.h>
  34
  35 #include "cmdline_parse.h"
  36 #include "cmdline.h"
  37
  38 //#define CMDLINE_DEBUG
  39 //#define debug_printf printf
  40 #define debug_printf(args...) do {} while(0)
  41
  42 /* isblank() needs _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE, so use our
  43  * own. */
  44 static int
  45 isblank2(char c)
  46 {
  47         if (c == ' ' ||
  48             c == '\t' )
  49                 return 1;
  50         return 0;
  51 }
  52
  53 static int
  54 isendofline(char c)
  55 {
  56         if (c == '\n' ||
  57             c == '\r' )
  58                 return 1;
  59         return 0;
  60 }
  61
  62 static int
  63 iscomment(char c)
  64 {
  65         if (c == '#')
  66                 return 1;
  67         return 0;
  68 }
  69
  70 int
  71 cmdline_isendoftoken(char c)
  72 {
  73         if (!c || iscomment(c) || isblank2(c) || isendofline(c))
  74                 return 1;
  75         return 0;
  76 }
  77
  78 static unsigned int
  79 nb_common_chars(const char * s1, const char * s2)
  80 {
  81         unsigned int i=0;
  82
  83         while (*s1==*s2 && *s1 && *s2) {
  84                 s1++;
  85                 s2++;
  86                 i++;
  87         }
  88         return i;
  89 }
  90
  91 /**
  92  * try to match the buffer with an instruction (only the first
  93  * nb_match_token tokens if != 0). Return 0 if we match all the
  94  * tokens, else the number of matched tokens, else -1.
  95  */
  96 static int
  97 match_inst(cmdline_parse_inst_t *inst, const char *buf, unsigned int nb_match_token,
  98            void * result_buf)
  99 {
 100         unsigned int token_num=0;
 101         cmdline_parse_token_hdr_t * token_p;
 102         unsigned int i=0;
 103         int n = 0;
 104         struct cmdline_token_hdr token_hdr;
 105
 106         token_p = inst->tokens[token_num];
 107         if (token_p)
 108                 memcpy(&token_hdr, token_p, sizeof(token_hdr));
 109
 110         /* check if we match all tokens of inst */
 111         while (token_p && (!nb_match_token || i<nb_match_token)) {
 112                 debug_printf("TK\n");
 113                 /* skip spaces */
 114                 while (isblank2(*buf)) {
 115                         buf++;
 116                 }
 117
 118                 /* end of buf */
 119                 if ( isendofline(*buf) || iscomment(*buf) )
 120                         break;
 121
 122                 n = token_hdr.ops->parse(token_p, buf, (result_buf ? result_buf+token_hdr.offset : NULL));
 123                 if ( n < 0 )
 124                         break;
 125                 debug_printf("TK parsed (len=%d)\n", n);
 126                 i++;
 127                 buf += n;
 128
 129                 token_num ++;
 130                 token_p = inst->tokens[token_num];
 131                 if (token_p)
 132                         memcpy(&token_hdr, token_p, sizeof(token_hdr));
 133         }
 134
 135         /* does not match */
 136         if (i==0)
 137                 return -1;
 138
 139         /* in case we want to match a specific num of token */
 140         if (nb_match_token) {
 141                 if (i == nb_match_token) {
 142                         return 0;
 143                 }
 144                 return i;
 145         }
 146
 147         /* we don't match all the tokens */
 148         if (token_p) {
 149                 return i;
 150         }
 151
 152         /* are there are some tokens more */
 153         while (isblank2(*buf)) {
 154                 buf++;
 155         }
 156
 157         /* end of buf */
 158         if ( isendofline(*buf) || iscomment(*buf) )
 159                 return 0;
 160
 161         /* garbage after inst */
 162         return i;
 163 }
 164
 165
 166 int
 167 cmdline_parse(struct cmdline *cl, const char * buf)
 168 {
 169         unsigned int inst_num=0;
 170         cmdline_parse_inst_t *inst;
 171         const char *curbuf;
 172         char result_buf[BUFSIZ]; /* XXX align, size zé in broblém */
 173         void (*f)(void *, struct cmdline *, void *) = NULL;
 174         void *data = NULL;
 175         int comment = 0;
 176         int linelen = 0;
 177         int parse_it = 0;
 178         int err = CMDLINE_PARSE_NOMATCH;
 179         int tok;
 180         cmdline_parse_ctx_t *ctx = cl->ctx;
 181 #ifdef CMDLINE_DEBUG
 182         char debug_buf[BUFSIZ];
 183 #endif
 184
 185         /*
 186          * - look if the buffer contains at least one line
 187          * - look if line contains only spaces or comments
 188          * - count line length
 189          */
 190         curbuf = buf;
 191         while (! isendofline(*curbuf)) {
 192                 if ( *curbuf == '\0' ) {
 193                         debug_printf("Incomplete buf (len=%d)\n", linelen);
 194                         return 0;
 195                 }
 196                 if ( iscomment(*curbuf) ) {
 197                         comment = 1;
 198                 }
 199                 if ( ! isblank2(*curbuf) && ! comment) {
 200                         parse_it = 1;
 201                 }
 202                 curbuf++;
 203                 linelen++;
 204         }
 205
 206         /* skip all endofline chars */
 207         while (isendofline(buf[linelen])) {
 208                 linelen++;
 209         }
 210
 211         /* empty line */
 212         if ( parse_it == 0 ) {
 213                 debug_printf("Empty line (len=%d)\n", linelen);
 214                 return linelen;
 215         }
 216
 217 #ifdef CMDLINE_DEBUG
 218         snprintf(debug_buf, (linelen>64 ? 64 : linelen), "%s", buf);
 219         debug_printf("Parse line : len=%d, <%s>\n", linelen, debug_buf);
 220 #endif
 221
 222         /* parse it !! */
 223         inst = ctx[inst_num];
 224         while (inst) {
 225                 debug_printf("INST %d\n", inst_num);
 226
 227                 /* fully parsed */
 228                 tok = match_inst(inst, buf, 0, result_buf);
 229
 230                 if (tok > 0) /* we matched at least one token */
 231                         err = CMDLINE_PARSE_BAD_ARGS;
 232
 233                 else if (!tok) {
 234                         debug_printf("INST fully parsed\n");
 235                         /* skip spaces */
 236                         while (isblank2(*curbuf)) {
 237                                 curbuf++;
 238                         }
 239
 240                         /* if end of buf -> there is no garbage after inst */
 241                         if (isendofline(*curbuf) || iscomment(*curbuf)) {
 242                                 if (!f) {
 243                                         memcpy(&f, &inst->f, sizeof(f));
 244                                         memcpy(&data, &inst->data, sizeof(data));
 245                                 }
 246                                 else {
 247                                         /* more than 1 inst matches */
 248                                         err = CMDLINE_PARSE_AMBIGUOUS;
 249                                         f=NULL;
 250                                         debug_printf("Ambiguous cmd\n");
 251                                         break;
 252                                 }
 253                         }
 254                 }
 255
 256                 inst_num ++;
 257                 inst = ctx[inst_num];
 258         }
 259
 260         /* call func */
 261         if (f) {
 262                 f(result_buf, cl, data);
 263         }
 264
 265         /* no match */
 266         else {
 267                 debug_printf("No match err=%d\n", err);
 268                 return err;
 269         }
 270
 271         return linelen;
 272 }
 273
 274 int
 275 cmdline_complete(struct cmdline *cl, const char *buf, int *state,
 276                  char *dst, unsigned int size)
 277 {
 278         const char *incomplete_token = buf;
 279         unsigned int inst_num = 0;
 280         cmdline_parse_inst_t *inst;
 281         cmdline_parse_token_hdr_t *token_p;
 282         struct cmdline_token_hdr token_hdr;
 283         char tmpbuf[64], completion_buf[64];
 284         unsigned int incomplete_token_len;
 285         int completion_len = -1;
 286         int nb_token = 0;
 287         unsigned int i, n;
 288         int l;
 289         unsigned int nb_completable;
 290         unsigned int nb_non_completable;
 291         unsigned int local_state=0;
 292         char *help_str;
 293         cmdline_parse_ctx_t *ctx = cl->ctx;
 294
 295         debug_printf("%s called\n", __FUNCTION__);
 296         /* count the number of complete token to parse */
 297         for (i=0 ; buf[i] ; i++) {
 298                 if (!isblank2(buf[i]) && isblank2(buf[i+1]))
 299                         nb_token++;
 300                 if (isblank2(buf[i]) && !isblank2(buf[i+1]))
 301                         incomplete_token = buf+i+1;
 302         }
 303         incomplete_token_len = strlen(incomplete_token);
 304
 305         /* first call -> do a first pass */
 306         if (*state <= 0) {
 307                 debug_printf("try complete <%s>\n", buf);
 308                 debug_printf("there is %d complete tokens, <%s> is incomplete\n", nb_token, incomplete_token);
 309
 310                 nb_completable = 0;
 311                 nb_non_completable = 0;
 312
 313                 inst = ctx[inst_num];
 314                 while (inst) {
 315                         /* parse the first tokens of the inst */
 316                         if (nb_token && match_inst(inst, buf, nb_token, NULL))
 317                                 goto next;
 318
 319                         debug_printf("instruction match \n");
 320                         token_p = inst->tokens[nb_token];
 321                         if (token_p)
 322                                 memcpy(&token_hdr, token_p, sizeof(token_hdr));
 323
 324                         /* non completable */
 325                         if (!token_p ||
 326                             !token_hdr.ops->complete_get_nb ||
 327                             !token_hdr.ops->complete_get_elt ||
 328                             (n = token_hdr.ops->complete_get_nb(token_p)) == 0) {
 329                                 nb_non_completable++;
 330                                 goto next;
 331                         }
 332
 333                         debug_printf("%d choices for this token\n", n);
 334                         for (i=0 ; i<n ; i++) {
 335                                 if (token_hdr.ops->complete_get_elt(token_p, i, tmpbuf, sizeof(tmpbuf)) < 0)
 336                                         continue;
 337                                 strcat(tmpbuf, " "); /* we have at least room for one char */
 338                                 debug_printf("   choice <%s>\n", tmpbuf);
 339                                 /* does the completion match the beginning of the word ? */
 340                                 if (!strncmp(incomplete_token, tmpbuf, incomplete_token_len)) {
 341                                         if (completion_len == -1) {
 342                                                 strcpy(completion_buf, tmpbuf+incomplete_token_len);
 343                                                 completion_len = strlen(tmpbuf+incomplete_token_len);
 344
 345                                         }
 346                                         else {
 347                                                 completion_len = nb_common_chars(completion_buf,
 348                                                                                  tmpbuf+incomplete_token_len);
 349                                                 completion_buf[completion_len] = 0;
 350                                         }
 351                                         nb_completable++;
 352                                 }
 353                         }
 354                 next:
 355                         inst_num ++;
 356                         inst = ctx[inst_num];
 357                 }
 358
 359                 debug_printf("total choices %d for this completion\n", nb_completable);
 360
 361                 /* no possible completion */
 362                 if (nb_completable == 0 && nb_non_completable == 0)
 363                         return 0;
 364
 365                 /* if multichoice is not required */
 366                 if (*state == 0 && incomplete_token_len > 0) {
 367                         /* one or several choices starting with the
 368                            same chars */
 369                         if (completion_len > 0) {
 370                                 if (completion_len + 1 > size)
 371                                         return 0;
 372
 373                                 strcpy(dst, completion_buf);
 374                                 return 2;
 375                         }
 376                 }
 377         }
 378
 379         /* init state correctly */
 380         if (*state == -1)
 381                 *state = 0;
 382
 383         debug_printf("Multiple choice STATE=%d\n", *state);
 384
 385         inst_num = 0;
 386         inst = ctx[inst_num];
 387         while (inst) {
 388                 /* we need to redo it */
 389                 inst = ctx[inst_num];
 390
 391                 if (nb_token && match_inst(inst, buf, nb_token, NULL))
 392                         goto next2;
 393
 394                 token_p = inst->tokens[nb_token];
 395                 if (token_p)
 396                         memcpy(&token_hdr, token_p, sizeof(token_hdr));
 397
 398                 /* one choice for this token */
 399                 if (!token_p ||
 400                     !token_hdr.ops->complete_get_nb ||
 401                     !token_hdr.ops->complete_get_elt ||
 402                     (n = token_hdr.ops->complete_get_nb(token_p)) == 0) {
 403                         if (local_state < *state) {
 404                                 local_state++;
 405                                 goto next2;
 406                         }
 407                         (*state)++;
 408                         if (token_p && token_hdr.ops->get_help) {
 409                                 token_hdr.ops->get_help(token_p, tmpbuf, sizeof(tmpbuf));
 410                                 help_str = inst->help_str;
 411                                 if (help_str)
 412                                         snprintf(dst, size, "[%s]: %s", tmpbuf, help_str);
 413                                 else
 414                                         snprintf(dst, size, "[%s]: No help", tmpbuf);
 415                         }
 416                         else {
 417                                 snprintf(dst, size, "[RETURN]");
 418                         }
 419                         return 1;
 420                 }
 421
 422                 /* several choices */
 423                 for (i=0 ; i<n ; i++) {
 424                         if (token_hdr.ops->complete_get_elt(token_p, i, tmpbuf, sizeof(tmpbuf)) < 0)
 425                                 continue;
 426                         strcat(tmpbuf, " "); /* we have at least room for one char */
 427                         debug_printf("   choice <%s>\n", tmpbuf);
 428                         /* does the completion match the beginning of the word ? */
 429                         if (!strncmp(incomplete_token, tmpbuf, incomplete_token_len)) {
 430                                 if (local_state < *state) {
 431                                         local_state++;
 432                                         continue;
 433                                 }
 434                                 (*state)++;
 435                                 l=snprintf(dst, size, "%s", tmpbuf);
 436                                 if (l>=0 && token_hdr.ops->get_help) {
 437                                         token_hdr.ops->get_help(token_p, tmpbuf, sizeof(tmpbuf));
 438                                         help_str = inst->help_str;
 439                                         if (help_str)
 440                                                 snprintf(dst+l, size-l, "[%s]: %s", tmpbuf, help_str);
 441                                         else
 442                                                 snprintf(dst+l, size-l, "[%s]: No help", tmpbuf);
 443                                 }
 444
 445                                 return 1;
 446                         }
 447                 }
 448         next2:
 449                 inst_num ++;
 450                 inst = ctx[inst_num];
 451         }
 452         return 0;
 453 }
 454