src/kits/app/LinkReceiver.cpp

   1 /*
   2  * Copyright 2001-2011, Haiku.
   3  * Distributed under the terms of the MIT License.
   4  *
   5  * Authors:
   6  *              Pahtz <pahtz@yahoo.com.au>
   7  *              Axel Dörfler
   8  *              Stephan Aßmus <superstippi@gmx.de>
   9  *              Artur Wyszynski <harakash@gmail.com>
  10  */
  11
  12
  13 /*! Class for low-overhead port-based messaging */
  14
  15
  16 #include <LinkReceiver.h>
  17
  18 #include <stdlib.h>
  19 #include <string.h>
  20 #include <new>
  21
  22 #include <ServerProtocol.h>
  23 #include <String.h>
  24 #include <Region.h>
  25 #include <GradientLinear.h>
  26 #include <GradientRadial.h>
  27 #include <GradientRadialFocus.h>
  28 #include <GradientDiamond.h>
  29 #include <GradientConic.h>
  30
  31 #include "link_message.h"
  32
  33 //#define DEBUG_BPORTLINK
  34 #ifdef DEBUG_BPORTLINK
  35 #       include <stdio.h>
  36 #       define STRACE(x) printf x
  37 #else
  38 #       define STRACE(x) ;
  39 #endif
  40
  41 //#define TRACE_LINK_RECEIVER_GRADIENTS
  42 #ifdef TRACE_LINK_RECEIVER_GRADIENTS
  43 #       include <OS.h>
  44 #       define GTRACE(x) debug_printf x
  45 #else
  46 #       define GTRACE(x) ;
  47 #endif
  48
  49
  50 namespace BPrivate {
  51
  52
  53 LinkReceiver::LinkReceiver(port_id port)
  54         :
  55         fReceivePort(port), fRecvBuffer(NULL), fRecvPosition(0), fRecvStart(0),
  56         fRecvBufferSize(0), fDataSize(0),
  57         fReplySize(0), fReadError(B_OK)
  58 {
  59 }
  60
  61
  62 LinkReceiver::~LinkReceiver()
  63 {
  64         free(fRecvBuffer);
  65 }
  66
  67
  68 void
  69 LinkReceiver::SetPort(port_id port)
  70 {
  71         fReceivePort = port;
  72 }
  73
  74
  75 status_t
  76 LinkReceiver::GetNextMessage(int32 &code, bigtime_t timeout)
  77 {
  78         fReadError = B_OK;
  79
  80         int32 remaining = fDataSize - (fRecvStart + fReplySize);
  81         STRACE(("info: LinkReceiver GetNextReply() reports %ld bytes remaining in buffer.\n", remaining));
  82
  83         // find the position of the next message header in the buffer
  84         message_header *header;
  85         if (remaining <= 0) {
  86                 status_t err = ReadFromPort(timeout);
  87                 if (err < B_OK)
  88                         return err;
  89                 remaining = fDataSize;
  90                 header = (message_header *)fRecvBuffer;
  91         } else {
  92                 fRecvStart += fReplySize;       // start of the next message
  93                 fRecvPosition = fRecvStart;
  94                 header = (message_header *)(fRecvBuffer + fRecvStart);
  95         }
  96
  97         // check we have a well-formed message
  98         if (remaining < (int32)sizeof(message_header)) {
  99                 // we don't have enough data for a complete header
 100                 STRACE(("error info: LinkReceiver remaining %ld bytes is less than header size.\n", remaining));
 101                 ResetBuffer();
 102                 return B_ERROR;
 103         }
 104
 105         fReplySize = header->size;
 106         if (fReplySize > remaining || fReplySize < (int32)sizeof(message_header)) {
 107                 STRACE(("error info: LinkReceiver message size of %ld bytes smaller than header size.\n", fReplySize));
 108                 ResetBuffer();
 109                 return B_ERROR;
 110         }
 111
 112         code = header->code;
 113         fRecvPosition += sizeof(message_header);
 114
 115         STRACE(("info: LinkReceiver got header %ld [%ld %ld %ld] from port %ld.\n",
 116                 header->code, fReplySize, header->code, header->flags, fReceivePort));
 117
 118         return B_OK;
 119 }
 120
 121
 122 bool
 123 LinkReceiver::HasMessages() const
 124 {
 125         return fDataSize - (fRecvStart + fReplySize) > 0
 126                 || port_count(fReceivePort) > 0;
 127 }
 128
 129
 130 bool
 131 LinkReceiver::NeedsReply() const
 132 {
 133         if (fReplySize == 0)
 134                 return false;
 135
 136         message_header *header = (message_header *)(fRecvBuffer + fRecvStart);
 137         return (header->flags & kNeedsReply) != 0;
 138 }
 139
 140
 141 int32
 142 LinkReceiver::Code() const
 143 {
 144         if (fReplySize == 0)
 145                 return B_ERROR;
 146
 147         message_header *header = (message_header *)(fRecvBuffer + fRecvStart);
 148         return header->code;
 149 }
 150
 151
 152 void
 153 LinkReceiver::ResetBuffer()
 154 {
 155         fRecvPosition = 0;
 156         fRecvStart = 0;
 157         fDataSize = 0;
 158         fReplySize = 0;
 159 }
 160
 161
 162 status_t
 163 LinkReceiver::AdjustReplyBuffer(bigtime_t timeout)
 164 {
 165         // Here we take advantage of the compiler's dead-code elimination
 166         if (kInitialBufferSize == kMaxBufferSize) {
 167                 // fixed buffer size
 168
 169                 if (fRecvBuffer != NULL)
 170                         return B_OK;
 171
 172                 fRecvBuffer = (char *)malloc(kInitialBufferSize);
 173                 if (fRecvBuffer == NULL)
 174                         return B_NO_MEMORY;
 175
 176                 fRecvBufferSize = kInitialBufferSize;
 177         } else {
 178                 STRACE(("info: LinkReceiver getting port_buffer_size().\n"));
 179
 180                 ssize_t bufferSize;
 181                 do {
 182                         bufferSize = port_buffer_size_etc(fReceivePort,
 183                                 timeout == B_INFINITE_TIMEOUT ? B_RELATIVE_TIMEOUT : 0,
 184                                 timeout);
 185                 } while (bufferSize == B_INTERRUPTED);
 186
 187                 STRACE(("info: LinkReceiver got port_buffer_size() = %ld.\n", bufferSize));
 188
 189                 if (bufferSize < 0)
 190                         return (status_t)bufferSize;
 191
 192                 // make sure our receive buffer is large enough
 193                 if (bufferSize > fRecvBufferSize) {
 194                         if (bufferSize <= (ssize_t)kInitialBufferSize)
 195                                 bufferSize = (ssize_t)kInitialBufferSize;
 196                         else
 197                                 bufferSize = (bufferSize + B_PAGE_SIZE - 1) & ~(B_PAGE_SIZE - 1);
 198
 199                         if (bufferSize > (ssize_t)kMaxBufferSize)
 200                                 return B_ERROR; // we can't continue
 201
 202                         STRACE(("info: LinkReceiver setting receive buffersize to %ld.\n", bufferSize));
 203                         char *buffer = (char *)malloc(bufferSize);
 204                         if (buffer == NULL)
 205                                 return B_NO_MEMORY;
 206
 207                         free(fRecvBuffer);
 208                         fRecvBuffer = buffer;
 209                         fRecvBufferSize = bufferSize;
 210                 }
 211         }
 212
 213         return B_OK;
 214 }
 215
 216
 217 status_t
 218 LinkReceiver::ReadFromPort(bigtime_t timeout)
 219 {
 220         // we are here so it means we finished reading the buffer contents
 221         ResetBuffer();
 222
 223         status_t err = AdjustReplyBuffer(timeout);
 224         if (err < B_OK)
 225                 return err;
 226
 227         int32 code;
 228         ssize_t bytesRead;
 229
 230         STRACE(("info: LinkReceiver reading port %ld.\n", fReceivePort));
 231         while (true) {
 232                 if (timeout != B_INFINITE_TIMEOUT) {
 233                         do {
 234                                 bytesRead = read_port_etc(fReceivePort, &code, fRecvBuffer,
 235                                         fRecvBufferSize, B_TIMEOUT, timeout);
 236                         } while (bytesRead == B_INTERRUPTED);
 237                 } else {
 238                         do {
 239                                 bytesRead = read_port(fReceivePort, &code, fRecvBuffer,
 240                                         fRecvBufferSize);
 241                         } while (bytesRead == B_INTERRUPTED);
 242                 }
 243
 244                 STRACE(("info: LinkReceiver read %ld bytes.\n", bytesRead));
 245                 if (bytesRead < B_OK)
 246                         return bytesRead;
 247
 248                 // we just ignore incorrect messages, and don't bother our caller
 249
 250                 if (code != kLinkCode) {
 251                         STRACE(("wrong port message %lx received.\n", code));
 252                         continue;
 253                 }
 254
 255                 // port read seems to be valid
 256                 break;
 257         }
 258
 259         fDataSize = bytesRead;
 260         return B_OK;
 261 }
 262
 263
 264 status_t
 265 LinkReceiver::Read(void *data, ssize_t passedSize)
 266 {
 267 //      STRACE(("info: LinkReceiver Read()ing %ld bytes...\n", size));
 268         ssize_t size = passedSize;
 269
 270         if (fReadError < B_OK)
 271                 return fReadError;
 272
 273         if (data == NULL || size < 1) {
 274                 fReadError = B_BAD_VALUE;
 275                 return B_BAD_VALUE;
 276         }
 277
 278         if (fDataSize == 0 || fReplySize == 0)
 279                 return B_NO_INIT;       // need to call GetNextReply() first
 280
 281         bool useArea = false;
 282         if ((size_t)size >= kMaxBufferSize) {
 283                 useArea = true;
 284                 size = sizeof(area_id);
 285         }
 286
 287         if (fRecvPosition + size > fRecvStart + fReplySize) {
 288                 // reading past the end of current message
 289                 fReadError = B_BAD_VALUE;
 290                 return B_BAD_VALUE;
 291         }
 292
 293         if (useArea) {
 294                 area_id sourceArea;
 295                 memcpy((void*)&sourceArea, fRecvBuffer + fRecvPosition, size);
 296
 297                 area_info areaInfo;
 298                 if (get_area_info(sourceArea, &areaInfo) < B_OK)
 299                         fReadError = B_BAD_VALUE;
 300
 301                 if (fReadError >= B_OK) {
 302                         void* areaAddress = areaInfo.address;
 303
 304                         if (areaAddress && sourceArea >= B_OK) {
 305                                 memcpy(data, areaAddress, passedSize);
 306                                 delete_area(sourceArea);
 307                         }
 308                 }
 309         } else {
 310                 memcpy(data, fRecvBuffer + fRecvPosition, size);
 311         }
 312         fRecvPosition += size;
 313         return fReadError;
 314 }
 315
 316
 317 status_t
 318 LinkReceiver::ReadString(char** _string, size_t* _length)
 319 {
 320         int32 length = 0;
 321         status_t status = Read<int32>(&length);
 322
 323         if (status < B_OK)
 324                 return status;
 325
 326         char *string;
 327         if (length < 0) {
 328                 status = B_ERROR;
 329                 goto err;
 330         }
 331
 332         string = (char *)malloc(length + 1);
 333         if (string == NULL) {
 334                 status = B_NO_MEMORY;
 335                 goto err;
 336         }
 337
 338         if (length > 0) {
 339                 status = Read(string, length);
 340                 if (status < B_OK) {
 341                         free(string);
 342                         return status;
 343                 }
 344         }
 345
 346         // make sure the string is null terminated
 347         string[length] = '\0';
 348
 349         if (_length)
 350                 *_length = length;
 351
 352         *_string = string;
 353
 354         return B_OK;
 355
 356 err:
 357         fRecvPosition -= sizeof(int32);
 358                 // rewind the transaction
 359         return status;
 360 }
 361
 362
 363 status_t
 364 LinkReceiver::ReadString(BString &string, size_t* _length)
 365 {
 366         int32 length = 0;
 367         status_t status = Read<int32>(&length);
 368
 369         if (status < B_OK)
 370                 return status;
 371
 372         if (length < 0) {
 373                 status = B_ERROR;
 374                 goto err;
 375         }
 376
 377         if (length > 0) {
 378                 char* buffer = string.LockBuffer(length + 1);
 379                 if (buffer == NULL) {
 380                         status = B_NO_MEMORY;
 381                         goto err;
 382                 }
 383
 384                 status = Read(buffer, length);
 385                 if (status < B_OK) {
 386                         string.UnlockBuffer();
 387                         goto err;
 388                 }
 389
 390                 // make sure the string is null terminated
 391                 buffer[length] = '\0';
 392                 string.UnlockBuffer(length);
 393         } else
 394                 string = "";
 395
 396         if (_length)
 397                 *_length = length;
 398
 399         return B_OK;
 400
 401 err:
 402         fRecvPosition -= sizeof(int32);
 403                 // rewind the transaction
 404         return status;
 405 }
 406
 407
 408 status_t
 409 LinkReceiver::ReadString(char *buffer, size_t bufferLength)
 410 {
 411         int32 length = 0;
 412         status_t status = Read<int32>(&length);
 413
 414         if (status < B_OK)
 415                 return status;
 416
 417         if (length >= (int32)bufferLength) {
 418                 status = B_BUFFER_OVERFLOW;
 419                 goto err;
 420         }
 421
 422         if (length < 0) {
 423                 status = B_ERROR;
 424                 goto err;
 425         }
 426
 427         if (length > 0) {
 428                 status = Read(buffer, length);
 429                 if (status < B_OK)
 430                         goto err;
 431         }
 432
 433         // make sure the string is null terminated
 434         buffer[length] = '\0';
 435         return B_OK;
 436
 437 err:
 438         fRecvPosition -= sizeof(int32);
 439                 // rewind the transaction
 440         return status;
 441 }
 442
 443 status_t
 444 LinkReceiver::ReadRegion(BRegion* region)
 445 {
 446         status_t status = Read(&region->fCount, sizeof(int32));
 447         if (status >= B_OK)
 448                 status = Read(&region->fBounds, sizeof(clipping_rect));
 449         if (status >= B_OK) {
 450                 if (!region->_SetSize(region->fCount))
 451                         status = B_NO_MEMORY;
 452                 else {
 453                         status = Read(region->fData,
 454                                 region->fCount * sizeof(clipping_rect));
 455                 }
 456                 if (status < B_OK)
 457                         region->MakeEmpty();
 458         }
 459         return status;
 460 }
 461
 462
 463 static BGradient*
 464 gradient_for_type(BGradient::Type type)
 465 {
 466         switch (type) {
 467                 case BGradient::TYPE_LINEAR:
 468                         return new (std::nothrow) BGradientLinear();
 469                 case BGradient::TYPE_RADIAL:
 470                         return new (std::nothrow) BGradientRadial();
 471                 case BGradient::TYPE_RADIAL_FOCUS:
 472                         return new (std::nothrow) BGradientRadialFocus();
 473                 case BGradient::TYPE_DIAMOND:
 474                         return new (std::nothrow) BGradientDiamond();
 475                 case BGradient::TYPE_CONIC:
 476                         return new (std::nothrow) BGradientConic();
 477                 case BGradient::TYPE_NONE:
 478                         return new (std::nothrow) BGradient();
 479         }
 480         return NULL;
 481 }
 482
 483
 484 status_t
 485 LinkReceiver::ReadGradient(BGradient** _gradient)
 486 {
 487         GTRACE(("LinkReceiver::ReadGradient\n"));
 488
 489         BGradient::Type gradientType;
 490         int32 colorsCount;
 491         Read(&gradientType, sizeof(BGradient::Type));
 492         status_t status = Read(&colorsCount, sizeof(int32));
 493         if (status != B_OK)
 494                 return status;
 495
 496         BGradient* gradient = gradient_for_type(gradientType);
 497         if (!gradient)
 498                 return B_NO_MEMORY;
 499
 500         *_gradient = gradient;
 501
 502         if (colorsCount > 0) {
 503                 BGradient::ColorStop stop;
 504                 for (int i = 0; i < colorsCount; i++) {
 505                         if ((status = Read(&stop, sizeof(BGradient::ColorStop))) != B_OK)
 506                                 return status;
 507                         if (!gradient->AddColorStop(stop, i))
 508                                 return B_NO_MEMORY;
 509                 }
 510         }
 511
 512         switch (gradientType) {
 513                 case BGradient::TYPE_LINEAR:
 514                 {
 515                         GTRACE(("LinkReceiver::ReadGradient> type == TYPE_LINEAR\n"));
 516                         BGradientLinear* linear = (BGradientLinear*)gradient;
 517                         BPoint start;
 518                         BPoint end;
 519                         Read(&start, sizeof(BPoint));
 520                         if ((status = Read(&end, sizeof(BPoint))) != B_OK)
 521                                 return status;
 522                         linear->SetStart(start);
 523                         linear->SetEnd(end);
 524                         return B_OK;
 525                 }
 526                 case BGradient::TYPE_RADIAL:
 527                 {
 528                         GTRACE(("LinkReceiver::ReadGradient> type == TYPE_RADIAL\n"));
 529                         BGradientRadial* radial = (BGradientRadial*)gradient;
 530                         BPoint center;
 531                         float radius;
 532                         Read(&center, sizeof(BPoint));
 533                         if ((status = Read(&radius, sizeof(float))) != B_OK)
 534                                 return status;
 535                         radial->SetCenter(center);
 536                         radial->SetRadius(radius);
 537                         return B_OK;
 538                 }
 539                 case BGradient::TYPE_RADIAL_FOCUS:
 540                 {
 541                         GTRACE(("LinkReceiver::ReadGradient> type == TYPE_RADIAL_FOCUS\n"));
 542                         BGradientRadialFocus* radialFocus =
 543                                 (BGradientRadialFocus*)gradient;
 544                         BPoint center;
 545                         BPoint focal;
 546                         float radius;
 547                         Read(&center, sizeof(BPoint));
 548                         Read(&focal, sizeof(BPoint));
 549                         if ((status = Read(&radius, sizeof(float))) != B_OK)
 550                                 return status;
 551                         radialFocus->SetCenter(center);
 552                         radialFocus->SetFocal(focal);
 553                         radialFocus->SetRadius(radius);
 554                         return B_OK;
 555                 }
 556                 case BGradient::TYPE_DIAMOND:
 557                 {
 558                         GTRACE(("LinkReceiver::ReadGradient> type == TYPE_DIAMOND\n"));
 559                         BGradientDiamond* diamond = (BGradientDiamond*)gradient;
 560                         BPoint center;
 561                         if ((status = Read(&center, sizeof(BPoint))) != B_OK)
 562                                 return status;
 563                         diamond->SetCenter(center);
 564                         return B_OK;
 565                 }
 566                 case BGradient::TYPE_CONIC:
 567                 {
 568                         GTRACE(("LinkReceiver::ReadGradient> type == TYPE_CONIC\n"));
 569                         BGradientConic* conic = (BGradientConic*)gradient;
 570                         BPoint center;
 571                         float angle;
 572                         Read(&center, sizeof(BPoint));
 573                         if ((status = Read(&angle, sizeof(float))) != B_OK)
 574                                 return status;
 575                         conic->SetCenter(center);
 576                         conic->SetAngle(angle);
 577                         return B_OK;
 578                 }
 579                 case BGradient::TYPE_NONE:
 580                 {
 581                         GTRACE(("LinkReceiver::ReadGradient> type == TYPE_NONE\n"));
 582                         break;
 583                 }
 584         }
 585
 586         return B_ERROR;
 587 }
 588
 589
 590 }       // namespace BPrivate