lib/libusbhid/parse.c

   1 /*      $NetBSD: parse.c,v 1.5 2004/01/05 17:55:48 augustss Exp $       */
   2
   3 /*
   4  * Copyright (c) 1999, 2001 Lennart Augustsson <augustss@NetBSD.org>
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  */
  28
  29 #include <sys/cdefs.h>
  30 __RCSID("$NetBSD: parse.c,v 1.5 2004/01/05 17:55:48 augustss Exp $");
  31
  32 #include <assert.h>
  33 #include <stdlib.h>
  34 #include <string.h>
  35 #include <sys/time.h>
  36
  37 #include <dev/usb/usb.h>
  38 #include <dev/usb/usbhid.h>
  39
  40 #include "usbhid.h"
  41 #include "usbvar.h"
  42
  43 #define MAXUSAGE 100
  44 struct hid_data {
  45         u_char *start;
  46         u_char *end;
  47         u_char *p;
  48         hid_item_t cur;
  49         unsigned int usages[MAXUSAGE];
  50         int nusage;
  51         int minset;
  52         int logminsize;
  53         int multi;
  54         int multimax;
  55         int kindset;
  56         int reportid;
  57
  58         /*
  59          * The start of collection item has no report ID set, so save
  60          * it until we know the ID.
  61          */
  62         hid_item_t savedcoll;
  63         u_char hassavedcoll;
  64         /*
  65          * Absolute data position (bits) for input/output/feature.
  66          *  Assumes that hid_input, hid_output and hid_feature have
  67          *  values 0, 1 and 2.
  68          */
  69         unsigned int kindpos[3];
  70 };
  71
  72 static int min(int x, int y) { return x < y ? x : y; }
  73
  74 static int hid_get_item_raw(hid_data_t s, hid_item_t *h);
  75
  76 static void
  77 hid_clear_local(hid_item_t *c)
  78 {
  79
  80         _DIAGASSERT(c != NULL);
  81
  82         c->usage = 0;
  83         c->usage_minimum = 0;
  84         c->usage_maximum = 0;
  85         c->designator_index = 0;
  86         c->designator_minimum = 0;
  87         c->designator_maximum = 0;
  88         c->string_index = 0;
  89         c->string_minimum = 0;
  90         c->string_maximum = 0;
  91         c->set_delimiter = 0;
  92 }
  93
  94 hid_data_t
  95 hid_start_parse(report_desc_t d, int kindset, int id)
  96 {
  97         struct hid_data *s;
  98
  99         _DIAGASSERT(d != NULL);
 100
 101         s = malloc(sizeof *s);
 102         memset(s, 0, sizeof *s);
 103         s->start = s->p = d->data;
 104         s->end = d->data + d->size;
 105         s->kindset = kindset;
 106         s->reportid = id;
 107         s->hassavedcoll = 0;
 108         return (s);
 109 }
 110
 111 void
 112 hid_end_parse(hid_data_t s)
 113 {
 114
 115         _DIAGASSERT(s != NULL);
 116
 117         while (s->cur.next) {
 118                 hid_item_t *hi = s->cur.next->next;
 119                 free(s->cur.next);
 120                 s->cur.next = hi;
 121         }
 122         free(s);
 123 }
 124
 125 int
 126 hid_get_item(hid_data_t s, hid_item_t *h)
 127 {
 128         int r;
 129
 130         for (;;) {
 131                 r = hid_get_item_raw(s, h);
 132                 if (r <= 0)
 133                         break;
 134                 if (h->report_ID == s->reportid || s->reportid == -1)
 135                         break;
 136         }
 137         return (r);
 138 }
 139
 140 #define REPORT_SAVED_COLL \
 141         do { \
 142                 if (s->hassavedcoll) { \
 143                         *h = s->savedcoll; \
 144                         h->report_ID = c->report_ID; \
 145                         s->hassavedcoll = 0; \
 146                         return (1); \
 147                 } \
 148         } while(/*LINTED*/ 0)
 149
 150 static int
 151 hid_get_item_raw(hid_data_t s, hid_item_t *h)
 152 {
 153         hid_item_t *c;
 154         unsigned int bTag = 0, bType = 0, bSize;
 155         unsigned char *data;
 156         int dval;
 157         unsigned char *p;
 158         hid_item_t *hi;
 159         hid_item_t nc;
 160         int i;
 161         hid_kind_t retkind;
 162
 163         _DIAGASSERT(s != NULL);
 164         _DIAGASSERT(h != NULL);
 165
 166         c = &s->cur;
 167
 168  top:
 169         if (s->multimax) {
 170                 REPORT_SAVED_COLL;
 171                 if (c->logical_minimum >= c->logical_maximum) {
 172                         if (s->logminsize == 1)
 173                                 c->logical_minimum =(int8_t)c->logical_minimum;
 174                         else if (s->logminsize == 2)
 175                                 c->logical_minimum =(int16_t)c->logical_minimum;
 176                 }
 177                 if (s->multi < s->multimax) {
 178                         c->usage = s->usages[min(s->multi, s->nusage-1)];
 179                         s->multi++;
 180                         *h = *c;
 181                         /*
 182                          * 'multimax' is only non-zero if the current
 183                          *  item kind is input/output/feature
 184                          */
 185                         h->pos = s->kindpos[c->kind];
 186                         s->kindpos[c->kind] += c->report_size;
 187                         h->next = 0;
 188                         return (1);
 189                 } else {
 190                         c->report_count = s->multimax;
 191                         s->multimax = 0;
 192                         s->nusage = 0;
 193                         hid_clear_local(c);
 194                 }
 195         }
 196         for (;;) {
 197                 p = s->p;
 198                 if (p >= s->end)
 199                         return (0);
 200
 201                 bSize = *p++;
 202                 if (bSize == 0xfe) {
 203                         /* long item */
 204                         bSize = *p++;
 205                         bSize |= *p++ << 8;
 206                         bTag = *p++;
 207                         data = p;
 208                         p += bSize;
 209                 } else {
 210                         /* short item */
 211                         bTag = bSize >> 4;
 212                         bType = (bSize >> 2) & 3;
 213                         bSize &= 3;
 214                         if (bSize == 3) bSize = 4;
 215                         data = p;
 216                         p += bSize;
 217                 }
 218                 s->p = p;
 219                 /*
 220                  * The spec is unclear if the data is signed or unsigned.
 221                  */
 222                 switch(bSize) {
 223                 case 0:
 224                         dval = 0;
 225                         break;
 226                 case 1:
 227                         dval = /*(int8_t)*/*data++;
 228                         break;
 229                 case 2:
 230                         dval = *data++;
 231                         dval |= *data++ << 8;
 232                         dval = /*(int16_t)*/dval;
 233                         break;
 234                 case 4:
 235                         dval = *data++;
 236                         dval |= *data++ << 8;
 237                         dval |= *data++ << 16;
 238                         dval |= *data++ << 24;
 239                         break;
 240                 default:
 241                         return (-1);
 242                 }
 243
 244                 switch (bType) {
 245                 case 0:                 /* Main */
 246                         switch (bTag) {
 247                         case 8:         /* Input */
 248                                 retkind = hid_input;
 249                         ret:
 250                                 if (!(s->kindset & (1 << retkind))) {
 251                                         /* Drop the items of this kind */
 252                                         s->nusage = 0;
 253                                         continue;
 254                                 }
 255                                 c->kind = retkind;
 256                                 c->flags = dval;
 257                                 if (c->flags & HIO_VARIABLE) {
 258                                         s->multimax = c->report_count;
 259                                         s->multi = 0;
 260                                         c->report_count = 1;
 261                                         if (s->minset) {
 262                                                 for (i = c->usage_minimum;
 263                                                      i <= c->usage_maximum;
 264                                                      i++) {
 265                                                         s->usages[s->nusage] = i;
 266                                                         if (s->nusage < MAXUSAGE-1)
 267                                                                 s->nusage++;
 268                                                 }
 269                                                 c->usage_minimum = 0;
 270                                                 c->usage_maximum = 0;
 271                                                 s->minset = 0;
 272                                         }
 273                                         goto top;
 274                                 } else {
 275                                         if (s->minset)
 276                                                 c->usage = c->usage_minimum;
 277                                         *h = *c;
 278                                         h->next = 0;
 279                                         h->pos = s->kindpos[c->kind];
 280                                         s->kindpos[c->kind] +=
 281                                             c->report_size * c->report_count;
 282                                         hid_clear_local(c);
 283                                         s->minset = 0;
 284                                         return (1);
 285                                 }
 286                         case 9:         /* Output */
 287                                 retkind = hid_output;
 288                                 goto ret;
 289                         case 10:        /* Collection */
 290                                 c->kind = hid_collection;
 291                                 c->collection = dval;
 292                                 c->collevel++;
 293                                 nc = *c;
 294                                 hid_clear_local(c);
 295                                 /*c->report_ID = NO_REPORT_ID;*/
 296                                 s->nusage = 0;
 297                                 if (s->hassavedcoll) {
 298                                         *h = s->savedcoll;
 299                                         h->report_ID = nc.report_ID;
 300                                         s->savedcoll = nc;
 301                                         return (1);
 302                                 } else {
 303                                         s->hassavedcoll = 1;
 304                                         s->savedcoll = nc;
 305                                 }
 306                                 break;
 307                         case 11:        /* Feature */
 308                                 retkind = hid_feature;
 309                                 goto ret;
 310                         case 12:        /* End collection */
 311                                 REPORT_SAVED_COLL;
 312                                 c->kind = hid_endcollection;
 313                                 c->collevel--;
 314                                 *h = *c;
 315                                 /*hid_clear_local(c);*/
 316                                 s->nusage = 0;
 317                                 return (1);
 318                         default:
 319                                 return (-2);
 320                         }
 321                         break;
 322
 323                 case 1:         /* Global */
 324                         switch (bTag) {
 325                         case 0:
 326                                 c->_usage_page = dval << 16;
 327                                 break;
 328                         case 1:
 329                                 c->logical_minimum = dval;
 330                                 s->logminsize = bSize;
 331                                 break;
 332                         case 2:
 333                                 c->logical_maximum = dval;
 334                                 break;
 335                         case 3:
 336                                 c->physical_minimum = dval;
 337                                 break;
 338                         case 4:
 339                                 c->physical_maximum = dval;
 340                                 break;
 341                         case 5:
 342                                 c->unit_exponent = dval;
 343                                 break;
 344                         case 6:
 345                                 c->unit = dval;
 346                                 break;
 347                         case 7:
 348                                 c->report_size = dval;
 349                                 break;
 350                         case 8:
 351                                 c->report_ID = dval;
 352                                 s->kindpos[hid_input] =
 353                                     s->kindpos[hid_output] =
 354                                     s->kindpos[hid_feature] = 0;
 355                                 break;
 356                         case 9:
 357                                 c->report_count = dval;
 358                                 break;
 359                         case 10: /* Push */
 360                                 hi = malloc(sizeof *hi);
 361                                 *hi = s->cur;
 362                                 c->next = hi;
 363                                 break;
 364                         case 11: /* Pop */
 365                                 hi = c->next;
 366                                 s->cur = *hi;
 367                                 free(hi);
 368                                 break;
 369                         default:
 370                                 return (-3);
 371                         }
 372                         break;
 373                 case 2:         /* Local */
 374                         switch (bTag) {
 375                         case 0:
 376                                 c->usage = c->_usage_page | dval;
 377                                 if (s->nusage < MAXUSAGE)
 378                                         s->usages[s->nusage++] = c->usage;
 379                                 /* else XXX */
 380                                 break;
 381                         case 1:
 382                                 s->minset = 1;
 383                                 c->usage_minimum = c->_usage_page | dval;
 384                                 break;
 385                         case 2:
 386                                 c->usage_maximum = c->_usage_page | dval;
 387                                 break;
 388                         case 3:
 389                                 c->designator_index = dval;
 390                                 break;
 391                         case 4:
 392                                 c->designator_minimum = dval;
 393                                 break;
 394                         case 5:
 395                                 c->designator_maximum = dval;
 396                                 break;
 397                         case 7:
 398                                 c->string_index = dval;
 399                                 break;
 400                         case 8:
 401                                 c->string_minimum = dval;
 402                                 break;
 403                         case 9:
 404                                 c->string_maximum = dval;
 405                                 break;
 406                         case 10:
 407                                 c->set_delimiter = dval;
 408                                 break;
 409                         default:
 410                                 return (-4);
 411                         }
 412                         break;
 413                 default:
 414                         return (-5);
 415                 }
 416         }
 417 }
 418
 419 int
 420 hid_report_size(report_desc_t r, enum hid_kind k, int id)
 421 {
 422         struct hid_data *d;
 423         hid_item_t h;
 424         int size;
 425
 426         _DIAGASSERT(r != NULL);
 427
 428         memset(&h, 0, sizeof h);
 429         size = 0;
 430         for (d = hid_start_parse(r, 1<<k, id); hid_get_item(d, &h); ) {
 431                 if (h.report_ID == id && h.kind == k) {
 432                         size = d->kindpos[k];
 433                 }
 434         }
 435         hid_end_parse(d);
 436         return ((size + 7) / 8);
 437 }
 438
 439 int
 440 hid_locate(report_desc_t desc, unsigned int u, enum hid_kind k,
 441            hid_item_t *h, int id)
 442 {
 443         hid_data_t d;
 444
 445         _DIAGASSERT(desc != NULL);
 446         _DIAGASSERT(h != NULL);
 447
 448         for (d = hid_start_parse(desc, 1<<k, id); hid_get_item(d, h); ) {
 449                 if (h->kind == k && !(h->flags & HIO_CONST) && h->usage == u) {
 450                         hid_end_parse(d);
 451                         return (1);
 452                 }
 453         }
 454         hid_end_parse(d);
 455         h->report_size = 0;
 456         return (0);
 457 }