reactos/lib/rtl/env.c

   1 /* COPYRIGHT:       See COPYING in the top level directory
   2  * PROJECT:         ReactOS system libraries
   3  * FILE:            lib/rtl/env.c
   4  * PURPOSE:         Environment functions
   5  * PROGRAMMER:      Eric Kohl
   6  */
   7
   8 /* INCLUDES ******************************************************************/
   9
  10 #include <rtl.h>
  11
  12 #define NDEBUG
  13 #include <debug.h>
  14
  15 PPEB NTAPI RtlpCurrentPeb(VOID);
  16 /* FUNCTIONS *****************************************************************/
  17
  18 /*
  19  * @implemented
  20  */
  21 NTSTATUS NTAPI
  22 RtlCreateEnvironment(BOOLEAN Inherit,
  23                      PWSTR *Environment)
  24 {
  25    MEMORY_BASIC_INFORMATION MemInfo;
  26    PVOID EnvPtr = NULL;
  27    NTSTATUS Status = STATUS_SUCCESS;
  28    ULONG RegionSize = PAGE_SIZE;
  29
  30    if (Inherit == TRUE)
  31    {
  32       RtlAcquirePebLock();
  33
  34       if (NtCurrentPeb()->ProcessParameters->Environment != NULL)
  35       {
  36          Status = NtQueryVirtualMemory(NtCurrentProcess(),
  37                                        NtCurrentPeb()->ProcessParameters->Environment,
  38                                        MemoryBasicInformation,
  39                                        &MemInfo,
  40                                        sizeof(MEMORY_BASIC_INFORMATION),
  41                                        NULL);
  42          if (!NT_SUCCESS(Status))
  43          {
  44             RtlReleasePebLock();
  45             *Environment = NULL;
  46             return(Status);
  47          }
  48
  49          RegionSize = MemInfo.RegionSize;
  50          Status = NtAllocateVirtualMemory(NtCurrentProcess(),
  51                                           &EnvPtr,
  52                                           0,
  53                                           &RegionSize,
  54                                           MEM_RESERVE | MEM_COMMIT,
  55                                           PAGE_READWRITE);
  56          if (!NT_SUCCESS(Status))
  57          {
  58             RtlReleasePebLock();
  59             *Environment = NULL;
  60             return(Status);
  61          }
  62
  63          memmove(EnvPtr,
  64                  NtCurrentPeb ()->ProcessParameters->Environment,
  65                  MemInfo.RegionSize);
  66
  67          *Environment = EnvPtr;
  68       }
  69
  70       RtlReleasePebLock ();
  71    }
  72    else
  73    {
  74       Status = NtAllocateVirtualMemory(NtCurrentProcess(),
  75                                        &EnvPtr,
  76                                        0,
  77                                        &RegionSize,
  78                                        MEM_RESERVE | MEM_COMMIT,
  79                                        PAGE_READWRITE);
  80       if (NT_SUCCESS(Status))
  81       {
  82          memset(EnvPtr,
  83                 0,
  84                 RegionSize);
  85          *Environment = EnvPtr;
  86       }
  87    }
  88
  89    return(Status);
  90 }
  91
  92
  93 /*
  94  * @implemented
  95  */
  96 VOID NTAPI
  97 RtlDestroyEnvironment(PWSTR Environment)
  98 {
  99    ULONG Size = 0;
 100
 101    NtFreeVirtualMemory(NtCurrentProcess(),
 102                        (PVOID)&Environment,
 103                        &Size,
 104                        MEM_RELEASE);
 105 }
 106
 107
 108 /*
 109  * @implemented
 110  */
 111 NTSTATUS NTAPI
 112 RtlExpandEnvironmentStrings_U(PWSTR Environment,
 113                               PUNICODE_STRING Source,
 114                               PUNICODE_STRING Destination,
 115                               PULONG Length)
 116 {
 117    UNICODE_STRING Variable;
 118    UNICODE_STRING Value;
 119    NTSTATUS ReturnStatus = STATUS_SUCCESS;
 120    NTSTATUS Status;
 121    PWSTR SourceBuffer;
 122    PWSTR DestBuffer;
 123    PWSTR CopyBuffer;
 124    PWSTR VariableEnd;
 125    ULONG SourceLength;
 126    ULONG DestMax;
 127    ULONG CopyLength;
 128    ULONG Tail;
 129    ULONG TotalLength = 1; /* for terminating NULL */
 130
 131    DPRINT("RtlExpandEnvironmentStrings_U %p %wZ %p %p\n",
 132           Environment, Source, Destination, Length);
 133
 134    SourceLength = Source->Length / sizeof(WCHAR);
 135    SourceBuffer = Source->Buffer;
 136    DestMax = Destination->MaximumLength / sizeof(WCHAR);
 137    DestBuffer = Destination->Buffer;
 138
 139    while (SourceLength)
 140    {
 141       if (*SourceBuffer != L'%')
 142       {
 143          CopyBuffer = SourceBuffer;
 144          CopyLength = 0;
 145          while (SourceLength != 0 && *SourceBuffer != L'%')
 146          {
 147             SourceBuffer++;
 148             CopyLength++;
 149             SourceLength--;
 150          }
 151       }
 152       else
 153       {
 154          /* Process environment variable. */
 155
 156          VariableEnd = SourceBuffer + 1;
 157          Tail = SourceLength - 1;
 158          while (*VariableEnd != L'%' && Tail != 0)
 159          {
 160             VariableEnd++;
 161             Tail--;
 162          }
 163
 164          if (Tail != 0)
 165          {
 166             Variable.MaximumLength =
 167             Variable.Length = (VariableEnd - (SourceBuffer + 1)) * sizeof(WCHAR);
 168             Variable.Buffer = SourceBuffer + 1;
 169
 170             Value.Length = 0;
 171             Value.MaximumLength = DestMax * sizeof(WCHAR);
 172             Value.Buffer = DestBuffer;
 173
 174             Status = RtlQueryEnvironmentVariable_U(Environment, &Variable,
 175                                                    &Value);
 176             if (NT_SUCCESS(Status) || Status == STATUS_BUFFER_TOO_SMALL)
 177             {
 178                 SourceBuffer = VariableEnd + 1;
 179                 SourceLength = Tail - 1;
 180                 TotalLength += Value.Length / sizeof(WCHAR);
 181                 if (Status != STATUS_BUFFER_TOO_SMALL)
 182                 {
 183                    DestBuffer += Value.Length / sizeof(WCHAR);
 184                    DestMax -= Value.Length / sizeof(WCHAR);
 185                 }
 186                 else
 187                 {
 188                    DestMax = 0;
 189                    ReturnStatus = STATUS_BUFFER_TOO_SMALL;
 190                 }
 191                 continue;
 192             }
 193             else
 194             {
 195                /* Variable not found. */
 196                CopyBuffer = SourceBuffer;
 197                CopyLength = SourceLength - Tail + 1;
 198                SourceLength -= CopyLength;
 199                SourceBuffer += CopyLength;
 200             }
 201          }
 202          else
 203          {
 204             /* Unfinished variable name. */
 205             CopyBuffer = SourceBuffer;
 206             CopyLength = SourceLength;
 207             SourceLength = 0;
 208          }
 209       }
 210
 211       TotalLength += CopyLength;
 212       if (DestMax)
 213       {
 214          if (DestMax < CopyLength)
 215          {
 216             CopyLength = DestMax;
 217             ReturnStatus = STATUS_BUFFER_TOO_SMALL;
 218          }
 219          RtlCopyMemory(DestBuffer, CopyBuffer, CopyLength * sizeof(WCHAR));
 220          DestMax -= CopyLength;
 221          DestBuffer += CopyLength;
 222       }
 223    }
 224
 225    /* NULL-terminate the buffer. */
 226    if (DestMax)
 227       *DestBuffer = 0;
 228    else
 229       ReturnStatus = STATUS_BUFFER_TOO_SMALL;
 230
 231    Destination->Length = (DestBuffer - Destination->Buffer) * sizeof(WCHAR);
 232    if (Length != NULL)
 233       *Length = TotalLength * sizeof(WCHAR);
 234
 235    DPRINT("Destination %wZ\n", Destination);
 236
 237    return ReturnStatus;
 238 }
 239
 240
 241 /*
 242  * @implemented
 243  */
 244 VOID NTAPI
 245 RtlSetCurrentEnvironment(PWSTR NewEnvironment,
 246                          PWSTR *OldEnvironment)
 247 {
 248    PVOID EnvPtr;
 249
 250    DPRINT("NewEnvironment 0x%p OldEnvironment 0x%p\n",
 251           NewEnvironment, OldEnvironment);
 252
 253    RtlAcquirePebLock();
 254
 255    EnvPtr = NtCurrentPeb()->ProcessParameters->Environment;
 256    NtCurrentPeb()->ProcessParameters->Environment = NewEnvironment;
 257
 258    if (OldEnvironment != NULL)
 259       *OldEnvironment = EnvPtr;
 260
 261    RtlReleasePebLock();
 262 }
 263
 264
 265 /*
 266  * @implemented
 267  */
 268 NTSTATUS NTAPI
 269 RtlSetEnvironmentVariable(PWSTR *Environment,
 270                           PUNICODE_STRING Name,
 271                           PUNICODE_STRING Value)
 272 {
 273    MEMORY_BASIC_INFORMATION mbi;
 274    UNICODE_STRING var;
 275    int hole_len, new_len, env_len = 0;
 276    WCHAR *new_env = 0, *env_end = 0, *wcs, *env, *val = 0, *tail = 0, *hole = 0;
 277    PWSTR head = NULL;
 278    ULONG size = 0, new_size;
 279    LONG f = 1;
 280    NTSTATUS Status = STATUS_SUCCESS;
 281
 282    DPRINT("RtlSetEnvironmentVariable(Environment %p Name %wZ Value %wZ)\n",
 283           Environment, Name, Value);
 284
 285    /* Variable names can't contain a '=' except as a first character. */
 286    for (wcs = Name->Buffer + 1;
 287         wcs < Name->Buffer + (Name->Length / sizeof(WCHAR));
 288         wcs++)
 289    {
 290       if (*wcs == L'=')
 291           return STATUS_INVALID_PARAMETER;
 292    }
 293
 294    if (Environment)
 295    {
 296       env = *Environment;
 297    }
 298    else
 299    {
 300       RtlAcquirePebLock();
 301       env = NtCurrentPeb()->ProcessParameters->Environment;
 302    }
 303
 304    if (env)
 305    {
 306       /* get environment length */
 307       wcs = env_end = env;
 308       do
 309       {
 310          env_end += wcslen(env_end) + 1;
 311       }
 312       while (*env_end);
 313       env_end++;
 314       env_len = env_end - env;
 315       DPRINT("environment length %ld characters\n", env_len);
 316
 317       /* find where to insert */
 318       while (*wcs)
 319       {
 320          var.Buffer = wcs++;
 321          wcs = wcschr(wcs, L'=');
 322          if (wcs == NULL)
 323          {
 324             wcs = var.Buffer + wcslen(var.Buffer);
 325          }
 326          if (*wcs)
 327          {
 328             var.Length = (wcs - var.Buffer) * sizeof(WCHAR);
 329             var.MaximumLength = var.Length;
 330             val = ++wcs;
 331             wcs += wcslen(wcs);
 332             f = RtlCompareUnicodeString(&var, Name, TRUE);
 333             if (f >= 0)
 334             {
 335                if (f) /* Insert before found */
 336                {
 337                   hole = tail = var.Buffer;
 338                }
 339                else /* Exact match */
 340                {
 341                   head = var.Buffer;
 342                   tail = ++wcs;
 343                   hole = val;
 344                }
 345                goto found;
 346             }
 347          }
 348          wcs++;
 349       }
 350       hole = tail = wcs; /* Append to environment */
 351    }
 352
 353 found:
 354    if (Value != NULL && Value->Length > 0)
 355    {
 356       hole_len = tail - hole;
 357       /* calculate new environment size */
 358       new_size = Value->Length + sizeof(WCHAR);
 359       /* adding new variable */
 360       if (f)
 361          new_size += Name->Length + sizeof(WCHAR);
 362       new_len = new_size / sizeof(WCHAR);
 363       if (hole_len < new_len)
 364       {
 365          /* enlarge environment size */
 366          /* check the size of available memory */
 367          new_size += (env_len - hole_len) * sizeof(WCHAR);
 368          new_size = ROUNDUP(new_size, PAGE_SIZE);
 369          mbi.RegionSize = 0;
 370          DPRINT("new_size %lu\n", new_size);
 371
 372          if (env)
 373          {
 374             Status = NtQueryVirtualMemory(NtCurrentProcess(),
 375                                           env,
 376                                           MemoryBasicInformation,
 377                                           &mbi,
 378                                           sizeof(MEMORY_BASIC_INFORMATION),
 379                                           NULL);
 380             if (!NT_SUCCESS(Status))
 381             {
 382                if (Environment == NULL)
 383                {
 384                   RtlReleasePebLock();
 385                }
 386                return(Status);
 387             }
 388          }
 389
 390          if (new_size > mbi.RegionSize)
 391          {
 392             /* reallocate memory area */
 393             Status = NtAllocateVirtualMemory(NtCurrentProcess(),
 394                                              (PVOID)&new_env,
 395                                              0,
 396                                              &new_size,
 397                                              MEM_RESERVE | MEM_COMMIT,
 398                                              PAGE_READWRITE);
 399             if (!NT_SUCCESS(Status))
 400             {
 401                if (Environment == NULL)
 402                {
 403                   RtlReleasePebLock();
 404                }
 405                return(Status);
 406             }
 407
 408             if (env)
 409             {
 410                memmove(new_env,
 411                        env,
 412                        (hole - env) * sizeof(WCHAR));
 413                hole = new_env + (hole - env);
 414             }
 415             else
 416             {
 417                /* absolutely new environment */
 418                tail = hole = new_env;
 419                *hole = 0;
 420                env_end = hole + 1;
 421             }
 422          }
 423       }
 424
 425       /* move tail */
 426       memmove (hole + new_len, tail, (env_end - tail) * sizeof(WCHAR));
 427
 428       if (new_env)
 429       {
 430          /* we reallocated environment, let's free the old one */
 431          if (Environment)
 432             *Environment = new_env;
 433          else
 434             NtCurrentPeb()->ProcessParameters->Environment = new_env;
 435
 436          if (env)
 437          {
 438             size = 0;
 439             NtFreeVirtualMemory(NtCurrentProcess(),
 440                                 (PVOID)&env,
 441                                 &size,
 442                                 MEM_RELEASE);
 443          }
 444       }
 445
 446       /* and now copy given stuff */
 447       if (f)
 448       {
 449          /* copy variable name and '=' character */
 450          memmove(hole,
 451                  Name->Buffer,
 452                  Name->Length);
 453          hole += Name->Length / sizeof(WCHAR);
 454          *hole++ = L'=';
 455       }
 456
 457       /* copy value */
 458       memmove(hole,
 459               Value->Buffer,
 460               Value->Length);
 461       hole += Value->Length / sizeof(WCHAR);
 462       *hole = 0;
 463    }
 464    else
 465    {
 466       /* remove the environment variable */
 467       if (f == 0)
 468       {
 469          memmove(head,
 470                  tail,
 471                  (env_end - tail) * sizeof(WCHAR));
 472       }
 473       else
 474       {
 475          Status = STATUS_VARIABLE_NOT_FOUND;
 476       }
 477    }
 478
 479    if (Environment == NULL)
 480    {
 481       RtlReleasePebLock();
 482    }
 483
 484    return(Status);
 485 }
 486
 487
 488 /*
 489  * @implemented
 490  */
 491 NTSTATUS NTAPI
 492 RtlQueryEnvironmentVariable_U(PWSTR Environment,
 493                               PUNICODE_STRING Name,
 494                               PUNICODE_STRING Value)
 495 {
 496    NTSTATUS Status;
 497    PWSTR wcs;
 498    UNICODE_STRING var;
 499    PWSTR val;
 500    BOOLEAN SysEnvUsed = FALSE;
 501
 502    DPRINT("RtlQueryEnvironmentVariable_U Environment %p Variable %wZ Value %p\n",
 503           Environment, Name, Value);
 504
 505    if (Environment == NULL)
 506    {
 507       PPEB Peb = RtlpCurrentPeb();
 508       if (Peb) {
 509           Environment = Peb->ProcessParameters->Environment;
 510           SysEnvUsed = TRUE;
 511       }
 512    }
 513
 514    if (Environment == NULL)
 515    {
 516       return(STATUS_VARIABLE_NOT_FOUND);
 517    }
 518
 519    Value->Length = 0;
 520    if (SysEnvUsed == TRUE)
 521       RtlAcquirePebLock();
 522
 523    wcs = Environment;
 524    DPRINT("Starting search at :%p\n", wcs);
 525    while (*wcs)
 526    {
 527       var.Buffer = wcs++;
 528       wcs = wcschr(wcs, L'=');
 529       if (wcs == NULL)
 530       {
 531          wcs = var.Buffer + wcslen(var.Buffer);
 532          DPRINT("Search at :%S\n", wcs);
 533       }
 534       if (*wcs)
 535       {
 536          var.Length = var.MaximumLength = (wcs - var.Buffer) * sizeof(WCHAR);
 537          val = ++wcs;
 538          wcs += wcslen(wcs);
 539          DPRINT("Search at :%S\n", wcs);
 540
 541          if (RtlEqualUnicodeString(&var, Name, TRUE))
 542          {
 543             Value->Length = (wcs - val) * sizeof(WCHAR);
 544             if (Value->Length <= Value->MaximumLength)
 545             {
 546                memcpy(Value->Buffer, val,
 547                       min(Value->Length + sizeof(WCHAR), Value->MaximumLength));
 548                DPRINT("Value %S\n", val);
 549                DPRINT("Return STATUS_SUCCESS\n");
 550                Status = STATUS_SUCCESS;
 551             }
 552             else
 553             {
 554                DPRINT("Return STATUS_BUFFER_TOO_SMALL\n");
 555                Status = STATUS_BUFFER_TOO_SMALL;
 556             }
 557
 558             if (SysEnvUsed == TRUE)
 559                RtlReleasePebLock();
 560
 561             return(Status);
 562          }
 563       }
 564       wcs++;
 565    }
 566
 567    if (SysEnvUsed == TRUE)
 568       RtlReleasePebLock();
 569
 570    DPRINT("Return STATUS_VARIABLE_NOT_FOUND: %wZ\n", Name);
 571    return(STATUS_VARIABLE_NOT_FOUND);
 572 }
 573
 574 /* EOF */