dlls/kernel32/format_msg.c

   1 /*
   2  * FormatMessage implementation
   3  *
   4  * Copyright 1996 Marcus Meissner
   5  * Copyright 2009 Alexandre Julliard
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  20  */
  21
  22 #include "config.h"
  23
  24 #include <stdarg.h>
  25 #include <stdio.h>
  26 #include <string.h>
  27
  28 #include "ntstatus.h"
  29 #define WIN32_NO_STATUS
  30 #include "windef.h"
  31 #include "winbase.h"
  32 #include "winerror.h"
  33 #include "winternl.h"
  34 #include "winuser.h"
  35 #include "winnls.h"
  36 #include "wine/unicode.h"
  37 #include "kernel_private.h"
  38 #include "wine/debug.h"
  39
  40 WINE_DEFAULT_DEBUG_CHANNEL(resource);
  41
  42 struct format_args
  43 {
  44     ULONG_PTR    *args;
  45     __ms_va_list *list;
  46     int           last;
  47 };
  48
  49 /* Messages used by FormatMessage
  50  *
  51  * They can be specified either directly or using a message ID and
  52  * loading them from the resource.
  53  *
  54  * The resourcedata has following format:
  55  * start:
  56  * 0: DWORD nrofentries
  57  * nrofentries * subentry:
  58  *      0: DWORD firstentry
  59  *      4: DWORD lastentry
  60  *      8: DWORD offset from start to the stringentries
  61  *
  62  * (lastentry-firstentry) * stringentry:
  63  * 0: WORD len (0 marks end)    [ includes the 4 byte header length ]
  64  * 2: WORD flags
  65  * 4: CHAR[len-4]
  66  *      (stringentry i of a subentry refers to the ID 'firstentry+i')
  67  *
  68  * Yes, ANSI strings in win32 resources. Go figure.
  69  */
  70
  71 static const WCHAR FMTWSTR[] = { '%','s',0 };
  72
  73 /**********************************************************************
  74  *      load_message    (internal)
  75  */
  76 static LPWSTR load_message( HMODULE module, UINT id, WORD lang )
  77 {
  78     const MESSAGE_RESOURCE_ENTRY *mre;
  79     WCHAR *buffer;
  80     NTSTATUS status;
  81
  82     TRACE("module = %p, id = %08x\n", module, id );
  83
  84     if (!module) module = GetModuleHandleW( NULL );
  85     if ((status = RtlFindMessage( module, RT_MESSAGETABLE, lang, id, &mre )) != STATUS_SUCCESS)
  86     {
  87         SetLastError( RtlNtStatusToDosError(status) );
  88         return NULL;
  89     }
  90
  91     if (mre->Flags & MESSAGE_RESOURCE_UNICODE)
  92     {
  93         int len = (strlenW( (const WCHAR *)mre->Text ) + 1) * sizeof(WCHAR);
  94         if (!(buffer = HeapAlloc( GetProcessHeap(), 0, len ))) return NULL;
  95         memcpy( buffer, mre->Text, len );
  96     }
  97     else
  98     {
  99         int len = MultiByteToWideChar( CP_ACP, 0, (const char *)mre->Text, -1, NULL, 0 );
 100         if (!(buffer = HeapAlloc( GetProcessHeap(), 0, len * sizeof(WCHAR) ))) return NULL;
 101         MultiByteToWideChar( CP_ACP, 0, (const char*)mre->Text, -1, buffer, len );
 102     }
 103     TRACE("returning %s\n", wine_dbgstr_w(buffer));
 104     return buffer;
 105 }
 106
 107 /**********************************************************************
 108  *      get_arg    (internal)
 109  */
 110 static ULONG_PTR get_arg( int nr, DWORD flags, struct format_args *args )
 111 {
 112     if (nr == -1) nr = args->last + 1;
 113     if (args->list)
 114     {
 115         if (!args->args) args->args = HeapAlloc( GetProcessHeap(), 0, 99 * sizeof(ULONG_PTR) );
 116         while (nr > args->last)
 117             args->args[args->last++] = va_arg( *args->list, ULONG_PTR );
 118     }
 119     if (nr > args->last) args->last = nr;
 120     return args->args[nr - 1];
 121 }
 122
 123 /**********************************************************************
 124  *      format_insert    (internal)
 125  */
 126 static LPCWSTR format_insert( BOOL unicode_caller, int insert, LPCWSTR format,
 127                               DWORD flags, struct format_args *args,
 128                               LPWSTR *result )
 129 {
 130     static const WCHAR fmt_u[] = {'%','u',0};
 131     WCHAR *wstring = NULL, *p, fmt[256];
 132     ULONG_PTR arg;
 133     int size;
 134
 135     if (*format != '!')  /* simple string */
 136     {
 137         arg = get_arg( insert, flags, args );
 138         if (unicode_caller || !arg)
 139         {
 140             static const WCHAR nullW[] = {'(','n','u','l','l',')',0};
 141             const WCHAR *str = (const WCHAR *)arg;
 142
 143             if (!str) str = nullW;
 144             *result = HeapAlloc( GetProcessHeap(), 0, (strlenW(str) + 1) * sizeof(WCHAR) );
 145             strcpyW( *result, str );
 146         }
 147         else
 148         {
 149             const char *str = (const char *)arg;
 150             DWORD length = MultiByteToWideChar( CP_ACP, 0, str, -1, NULL, 0 );
 151             *result = HeapAlloc( GetProcessHeap(), 0, length * sizeof(WCHAR) );
 152             MultiByteToWideChar( CP_ACP, 0, str, -1, *result, length );
 153         }
 154         return format;
 155     }
 156
 157     format++;
 158     p = fmt;
 159     *p++ = '%';
 160
 161     while (*format == '0' ||
 162            *format == '+' ||
 163            *format == '-' ||
 164            *format == ' ' ||
 165            *format == '*' ||
 166            *format == '#')
 167     {
 168         if (*format == '*')
 169         {
 170             p += sprintfW( p, fmt_u, get_arg( insert, flags, args ));
 171             insert = -1;
 172             format++;
 173         }
 174         else *p++ = *format++;
 175     }
 176     while (isdigitW(*format)) *p++ = *format++;
 177
 178     if (*format == '.')
 179     {
 180         *p++ = *format++;
 181         if (*format == '*')
 182         {
 183             p += sprintfW( p, fmt_u, get_arg( insert, flags, args ));
 184             insert = -1;
 185             format++;
 186         }
 187         else
 188             while (isdigitW(*format)) *p++ = *format++;
 189     }
 190
 191     /* replicate MS bug: drop an argument when using va_list with width/precision */
 192     if (insert == -1 && args->list) args->last--;
 193     arg = get_arg( insert, flags, args );
 194
 195     /* check for ascii string format */
 196     if ((format[0] == 'h' && format[1] == 's') ||
 197         (format[0] == 'h' && format[1] == 'S') ||
 198         (unicode_caller && format[0] == 'S') ||
 199         (!unicode_caller && format[0] == 's'))
 200     {
 201         DWORD len = MultiByteToWideChar( CP_ACP, 0, (char *)arg, -1, NULL, 0 );
 202         wstring = HeapAlloc( GetProcessHeap(), 0, len * sizeof(WCHAR) );
 203         MultiByteToWideChar( CP_ACP, 0, (char *)arg, -1, wstring, len );
 204         arg = (ULONG_PTR)wstring;
 205         *p++ = 's';
 206     }
 207     /* check for ascii character format */
 208     else if ((format[0] == 'h' && format[1] == 'c') ||
 209              (format[0] == 'h' && format[1] == 'C') ||
 210              (unicode_caller && format[0] == 'C') ||
 211              (!unicode_caller && format[0] == 'c'))
 212     {
 213         char ch = arg;
 214         wstring = HeapAlloc( GetProcessHeap(), 0, 2 * sizeof(WCHAR) );
 215         MultiByteToWideChar( CP_ACP, 0, &ch, 1, wstring, 1 );
 216         wstring[1] = 0;
 217         arg = (ULONG_PTR)wstring;
 218         *p++ = 's';
 219     }
 220     /* check for wide string format */
 221     else if ((format[0] == 'l' && format[1] == 's') ||
 222              (format[0] == 'l' && format[1] == 'S') ||
 223              (format[0] == 'w' && format[1] == 's') ||
 224              (!unicode_caller && format[0] == 'S'))
 225     {
 226         *p++ = 's';
 227     }
 228     /* check for wide character format */
 229     else if ((format[0] == 'l' && format[1] == 'c') ||
 230              (format[0] == 'l' && format[1] == 'C') ||
 231              (format[0] == 'w' && format[1] == 'c') ||
 232              (!unicode_caller && format[0] == 'C'))
 233     {
 234         *p++ = 'c';
 235     }
 236     /* FIXME: handle I64 etc. */
 237     else while (*format && *format != '!') *p++ = *format++;
 238
 239     *p = 0;
 240     size = 256;
 241     for (;;)
 242     {
 243         WCHAR *ret = HeapAlloc( GetProcessHeap(), 0, size * sizeof(WCHAR) );
 244         int needed = snprintfW( ret, size, fmt, arg );
 245         if (needed == -1 || needed >= size)
 246         {
 247             HeapFree( GetProcessHeap(), 0, ret );
 248             size = max( needed + 1, size * 2 );
 249         }
 250         else
 251         {
 252             *result = ret;
 253             break;
 254         }
 255     }
 256
 257     while (*format && *format != '!') format++;
 258     if (*format == '!') format++;
 259
 260     HeapFree( GetProcessHeap(), 0, wstring );
 261     return format;
 262 }
 263
 264 struct _format_message_data
 265 {
 266     LPWSTR formatted;
 267     DWORD size;
 268     LPWSTR t;
 269     LPWSTR space;
 270     BOOL inspace;
 271     DWORD width, w;
 272 };
 273
 274 static void format_add_char(struct _format_message_data *fmd, WCHAR c)
 275 {
 276     *fmd->t++ = c;
 277     if (fmd->width && fmd->width != FORMAT_MESSAGE_MAX_WIDTH_MASK)
 278     {
 279         switch (c) {
 280         case '\r':
 281         case '\n':
 282             fmd->space = NULL;
 283             fmd->inspace = FALSE;
 284             fmd->w = 0;
 285             break;
 286         case ' ':
 287             if (!fmd->inspace)
 288                 fmd->space = fmd->t - 1;
 289             fmd->inspace = TRUE;
 290             fmd->w++;
 291             break;
 292         default:
 293             fmd->inspace = FALSE;
 294             fmd->w++;
 295         }
 296         if (fmd->w == fmd->width) {
 297             LPWSTR notspace;
 298             if (fmd->space) {
 299                 notspace = fmd->space;
 300                 while (*notspace == ' ' && notspace != fmd->t)
 301                     notspace++;
 302             } else
 303                 notspace = fmd->space = fmd->t;
 304             fmd->w = fmd->t - notspace;
 305             memmove(fmd->space+2, notspace, fmd->w * sizeof(*fmd->t));
 306             *fmd->space++ = '\r';
 307             *fmd->space++ = '\n';
 308             fmd->t = fmd->space + fmd->w;
 309             fmd->space = NULL;
 310             fmd->inspace = FALSE;
 311         }
 312     }
 313     if ((DWORD)(fmd->t - fmd->formatted) == fmd->size) {
 314         DWORD_PTR ispace = fmd->space - fmd->formatted;
 315         /* Allocate two extra characters so we can insert a '\r\n' in
 316          * the middle of a word.
 317          */
 318         fmd->formatted = HeapReAlloc(GetProcessHeap(), 0, fmd->formatted, (fmd->size * 2 + 2) * sizeof(WCHAR));
 319         fmd->t = fmd->formatted + fmd->size;
 320         if (fmd->space)
 321             fmd->space = fmd->formatted + ispace;
 322         fmd->size *= 2;
 323     }
 324 }
 325
 326 /**********************************************************************
 327  *      format_message    (internal)
 328  */
 329 static LPWSTR format_message( BOOL unicode_caller, DWORD dwFlags, LPCWSTR fmtstr,
 330                               struct format_args *format_args )
 331 {
 332     struct _format_message_data fmd;
 333     LPCWSTR f;
 334     BOOL eos = FALSE;
 335
 336     fmd.size = 100;
 337     fmd.formatted = fmd.t = HeapAlloc( GetProcessHeap(), 0, (fmd.size + 2) * sizeof(WCHAR) );
 338
 339     fmd.width = dwFlags & FORMAT_MESSAGE_MAX_WIDTH_MASK;
 340     fmd.w = 0;
 341     fmd.inspace = FALSE;
 342     fmd.space = NULL;
 343     f = fmtstr;
 344     while (*f && !eos) {
 345         if (*f=='%') {
 346             int insertnr;
 347             WCHAR *str,*x;
 348
 349             f++;
 350             switch (*f) {
 351             case '1':case '2':case '3':case '4':case '5':
 352             case '6':case '7':case '8':case '9':
 353                 if (dwFlags & FORMAT_MESSAGE_IGNORE_INSERTS)
 354                     goto ignore_inserts;
 355                 else if (((dwFlags & FORMAT_MESSAGE_ARGUMENT_ARRAY) && !format_args->args) ||
 356                         (!(dwFlags & FORMAT_MESSAGE_ARGUMENT_ARRAY) && !format_args->list))
 357                 {
 358                     SetLastError(ERROR_INVALID_PARAMETER);
 359                     HeapFree(GetProcessHeap(), 0, fmd.formatted);
 360                     return NULL;
 361                 }
 362                 insertnr = *f-'0';
 363                 switch (f[1]) {
 364                 case '0':case '1':case '2':case '3':
 365                 case '4':case '5':case '6':case '7':
 366                 case '8':case '9':
 367                     f++;
 368                     insertnr = insertnr*10 + *f-'0';
 369                     f++;
 370                     break;
 371                 default:
 372                     f++;
 373                     break;
 374                 }
 375                 f = format_insert( unicode_caller, insertnr, f, dwFlags, format_args, &str );
 376                 for (x = str; *x; x++) format_add_char(&fmd, *x);
 377                 HeapFree( GetProcessHeap(), 0, str );
 378                 break;
 379             case 'n':
 380                 format_add_char(&fmd, '\r');
 381                 format_add_char(&fmd, '\n');
 382                 f++;
 383                 break;
 384             case 'r':
 385                 format_add_char(&fmd, '\r');
 386                 f++;
 387                 break;
 388             case 't':
 389                 format_add_char(&fmd, '\t');
 390                 f++;
 391                 break;
 392             case '0':
 393                 eos = TRUE;
 394                 f++;
 395                 break;
 396             case '\0':
 397                 SetLastError(ERROR_INVALID_PARAMETER);
 398                 HeapFree(GetProcessHeap(), 0, fmd.formatted);
 399                 return NULL;
 400             ignore_inserts:
 401             default:
 402                 if (dwFlags & FORMAT_MESSAGE_IGNORE_INSERTS)
 403                     format_add_char(&fmd, '%');
 404                 format_add_char(&fmd, *f++);
 405                 break;
 406             }
 407         } else {
 408             WCHAR ch = *f;
 409             f++;
 410             if (ch == '\r') {
 411                 if (*f == '\n')
 412                     f++;
 413                 if(fmd.width)
 414                     format_add_char(&fmd, ' ');
 415                 else
 416                 {
 417                     format_add_char(&fmd, '\r');
 418                     format_add_char(&fmd, '\n');
 419                 }
 420             } else {
 421                 if (ch == '\n')
 422                 {
 423                     if(fmd.width)
 424                         format_add_char(&fmd, ' ');
 425                     else
 426                     {
 427                         format_add_char(&fmd, '\r');
 428                         format_add_char(&fmd, '\n');
 429                     }
 430                 }
 431                 else
 432                     format_add_char(&fmd, ch);
 433             }
 434         }
 435     }
 436     *fmd.t = '\0';
 437
 438     return fmd.formatted;
 439 }
 440
 441 /***********************************************************************
 442  *           FormatMessageA   (KERNEL32.@)
 443  */
 444 DWORD WINAPI FormatMessageA(
 445         DWORD   dwFlags,
 446         LPCVOID lpSource,
 447         DWORD   dwMessageId,
 448         DWORD   dwLanguageId,
 449         LPSTR   lpBuffer,
 450         DWORD   nSize,
 451         __ms_va_list* args )
 452 {
 453     struct format_args format_args;
 454     DWORD ret = 0;
 455     LPWSTR      target;
 456     DWORD       destlength;
 457     LPWSTR      from;
 458
 459     TRACE("(0x%x,%p,%d,0x%x,%p,%d,%p)\n",
 460           dwFlags,lpSource,dwMessageId,dwLanguageId,lpBuffer,nSize,args);
 461
 462     if (dwFlags & FORMAT_MESSAGE_ALLOCATE_BUFFER)
 463     {
 464         if (!lpBuffer)
 465         {
 466             SetLastError(ERROR_NOT_ENOUGH_MEMORY);
 467             return 0;
 468         }
 469         else
 470             *(LPSTR *)lpBuffer = NULL;
 471     }
 472
 473     if (dwFlags & FORMAT_MESSAGE_ARGUMENT_ARRAY)
 474     {
 475         format_args.args = (ULONG_PTR *)args;
 476         format_args.list = NULL;
 477         format_args.last = 0;
 478     }
 479     else
 480     {
 481         format_args.args = NULL;
 482         format_args.list = args;
 483         format_args.last = 0;
 484     }
 485
 486     from = NULL;
 487     if (dwFlags & FORMAT_MESSAGE_FROM_STRING)
 488     {
 489         DWORD length = MultiByteToWideChar(CP_ACP, 0, lpSource, -1, NULL, 0);
 490         from = HeapAlloc( GetProcessHeap(), 0, length * sizeof(WCHAR) );
 491         MultiByteToWideChar(CP_ACP, 0, lpSource, -1, from, length);
 492     }
 493     else if (dwFlags & (FORMAT_MESSAGE_FROM_HMODULE | FORMAT_MESSAGE_FROM_SYSTEM))
 494     {
 495         if (dwFlags & FORMAT_MESSAGE_FROM_HMODULE)
 496             from = load_message( (HMODULE)lpSource, dwMessageId, dwLanguageId );
 497         if (!from && (dwFlags & FORMAT_MESSAGE_FROM_SYSTEM))
 498             from = load_message( kernel32_handle, dwMessageId, dwLanguageId );
 499         if (!from) return 0;
 500     }
 501     else
 502     {
 503         SetLastError(ERROR_INVALID_PARAMETER);
 504         return 0;
 505     }
 506
 507     target = format_message( FALSE, dwFlags, from, &format_args );
 508     if (!target)
 509         goto failure;
 510
 511     TRACE("-- %s\n", debugstr_w(target));
 512
 513     /* Only try writing to an output buffer if there are processed characters
 514      * in the temporary output buffer. */
 515     if (*target)
 516     {
 517         destlength = WideCharToMultiByte(CP_ACP, 0, target, -1, NULL, 0, NULL, NULL);
 518         if (dwFlags & FORMAT_MESSAGE_ALLOCATE_BUFFER)
 519         {
 520             LPSTR buf = LocalAlloc(LMEM_ZEROINIT, max(nSize, destlength));
 521             WideCharToMultiByte(CP_ACP, 0, target, -1, buf, destlength, NULL, NULL);
 522             *((LPSTR*)lpBuffer) = buf;
 523         }
 524         else
 525         {
 526             if (nSize < destlength)
 527             {
 528                 SetLastError(ERROR_INSUFFICIENT_BUFFER);
 529                 goto failure;
 530             }
 531             WideCharToMultiByte(CP_ACP, 0, target, -1, lpBuffer, destlength, NULL, NULL);
 532         }
 533         ret = destlength - 1; /* null terminator */
 534     }
 535
 536 failure:
 537     HeapFree(GetProcessHeap(),0,target);
 538     HeapFree(GetProcessHeap(),0,from);
 539     if (!(dwFlags & FORMAT_MESSAGE_ARGUMENT_ARRAY)) HeapFree( GetProcessHeap(), 0, format_args.args );
 540     TRACE("-- returning %u\n", ret);
 541     return ret;
 542 }
 543
 544 /***********************************************************************
 545  *           FormatMessageW   (KERNEL32.@)
 546  */
 547 DWORD WINAPI FormatMessageW(
 548         DWORD   dwFlags,
 549         LPCVOID lpSource,
 550         DWORD   dwMessageId,
 551         DWORD   dwLanguageId,
 552         LPWSTR  lpBuffer,
 553         DWORD   nSize,
 554         __ms_va_list* args )
 555 {
 556     struct format_args format_args;
 557     DWORD ret = 0;
 558     LPWSTR target;
 559     DWORD talloced;
 560     LPWSTR from;
 561
 562     TRACE("(0x%x,%p,%d,0x%x,%p,%d,%p)\n",
 563           dwFlags,lpSource,dwMessageId,dwLanguageId,lpBuffer,nSize,args);
 564
 565     if (!lpBuffer)
 566     {
 567         SetLastError(ERROR_INVALID_PARAMETER);
 568         return 0;
 569     }
 570
 571     if (dwFlags & FORMAT_MESSAGE_ALLOCATE_BUFFER)
 572         *(LPWSTR *)lpBuffer = NULL;
 573
 574     if (dwFlags & FORMAT_MESSAGE_ARGUMENT_ARRAY)
 575     {
 576         format_args.args = (ULONG_PTR *)args;
 577         format_args.list = NULL;
 578         format_args.last = 0;
 579     }
 580     else
 581     {
 582         format_args.args = NULL;
 583         format_args.list = args;
 584         format_args.last = 0;
 585     }
 586
 587     from = NULL;
 588     if (dwFlags & FORMAT_MESSAGE_FROM_STRING) {
 589         from = HeapAlloc( GetProcessHeap(), 0, (strlenW(lpSource) + 1) *
 590             sizeof(WCHAR) );
 591         strcpyW( from, lpSource );
 592     }
 593     else if (dwFlags & (FORMAT_MESSAGE_FROM_HMODULE | FORMAT_MESSAGE_FROM_SYSTEM))
 594     {
 595         if (dwFlags & FORMAT_MESSAGE_FROM_HMODULE)
 596             from = load_message( (HMODULE)lpSource, dwMessageId, dwLanguageId );
 597         if (!from && (dwFlags & FORMAT_MESSAGE_FROM_SYSTEM))
 598             from = load_message( kernel32_handle, dwMessageId, dwLanguageId );
 599         if (!from) return 0;
 600     }
 601     else
 602     {
 603         SetLastError(ERROR_INVALID_PARAMETER);
 604         return 0;
 605     }
 606
 607     target = format_message( TRUE, dwFlags, from, &format_args );
 608     if (!target)
 609         goto failure;
 610
 611     talloced = strlenW(target)+1;
 612     TRACE("-- %s\n",debugstr_w(target));
 613
 614     /* Only allocate a buffer if there are processed characters in the
 615      * temporary output buffer. If a caller supplies the buffer, then
 616      * a null terminator will be written to it. */
 617     if (dwFlags & FORMAT_MESSAGE_ALLOCATE_BUFFER)
 618     {
 619         if (*target)
 620         {
 621             /* nSize is the MINIMUM size */
 622             *((LPVOID*)lpBuffer) = LocalAlloc(LMEM_ZEROINIT, max(nSize, talloced)*sizeof(WCHAR));
 623             strcpyW(*(LPWSTR*)lpBuffer, target);
 624         }
 625     }
 626     else
 627     {
 628         if (nSize < talloced)
 629         {
 630             SetLastError(ERROR_INSUFFICIENT_BUFFER);
 631             goto failure;
 632         }
 633         strcpyW(lpBuffer, target);
 634     }
 635
 636     ret = talloced - 1; /* null terminator */
 637 failure:
 638     HeapFree(GetProcessHeap(),0,target);
 639     HeapFree(GetProcessHeap(),0,from);
 640     if (!(dwFlags & FORMAT_MESSAGE_ARGUMENT_ARRAY)) HeapFree( GetProcessHeap(), 0, format_args.args );
 641     TRACE("-- returning %u\n", ret);
 642     return ret;
 643 }