642 lines
19 KiB
C
642 lines
19 KiB
C
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/***
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*heapinit.c - Initialze the heap
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*
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* Copyright (c) 1989-2001, Microsoft Corporation. All rights reserved.
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*
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*Purpose:
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*
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*Revision History:
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* 06-28-89 JCR Module created.
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* 06-30-89 JCR Added _heap_grow_emptylist
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* 11-13-89 GJF Fixed copyright
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* 11-15-89 JCR Moved _heap_abort routine to another module
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* 12-15-89 GJF Removed DEBUG286 stuff, did some tuning, changed header
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* file name to heap.h and made functions explicitly
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* _cdecl.
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* 12-19-89 GJF Removed plastdesc field from _heap_desc_ struct
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* 03-11-90 GJF Replaced _cdecl with _CALLTYPE1, added #include
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* <cruntime.h> and removed #include <register.h>.
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* 07-24-90 SBM Removed '32' from API names
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* 10-03-90 GJF New-style function declarators.
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* 12-04-90 SRW Changed to include <oscalls.h> instead of <doscalls.h>
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* 12-06-90 SRW Added _CRUISER_ and _WIN32 conditionals.
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* 02-01-91 SRW Changed for new VirtualAlloc interface (_WIN32_)
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* 03-05-91 GJF Added definition of _heap_resetsize (conditioned on
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* _OLDROVER_ not being #define-d).
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* 04-04-91 GJF Reduce _heap_regionsize to 1/2 a meg for Dosx32
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* (_WIN32_).
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* 04-05-91 GJF Temporary hack for Win32/DOS folks - special version
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* of _heap_init which calls HeapCreate. The change
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* conditioned on _WIN32DOS_.
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* 04-09-91 PNT Added _MAC_ conditional
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* 02-23-93 SKS Remove DOSX32 support under WIN32 ifdef
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* 04-06-93 SKS Replace _CRTAPI* with __cdecl
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* 04-26-93 SKS Add variable _heap_maxregsize (was _HEAP_MAXREGIONSIZE)
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* Initialize _heap_[max,]reg[,ion]size to Large defaults
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* heapinit() tests _osver to detect Small memory case
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* 05-06-93 SKS Add _heap_term() to return heap memory to the o.s.
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* 01-17-94 SKS Check _osver AND _winmajor to detect Small memory case.
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* 03-02-94 GJF Changed _heap_grow_emptylist so that it returns a
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* failure code rather than calling _heap_abort.
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* 03-30-94 GJF Made definitions/declarations of:
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* _heap_desc
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* _heap_descpages,
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* _heap_growsize (aka, _amblksiz),
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* _heap_maxregsize
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* _heap_regionsize
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* _heap_regions
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* conditional on ndef DLL_FOR_WIN32S.
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* 02-08-95 GJF Removed obsolete _OLDROVER_ support.
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* 02-14-95 GJF Appended Mac version of source file.
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* 04-30-95 GJF Spliced on winheap version.
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* 03-06-96 GJF Added initialization and termination code for the
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* small-block heap.
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* 04-22-97 GJF Changed _heap_init to return 1 for success, 0 for
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* failure.
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* 05-30-96 GJF Minor changes for latest version of small-block heap.
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* 05-22-97 RDK New small-block heap scheme implemented.
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* 07-23-97 GJF Changed _heap_init() slightly to accomodate optional
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* heap running directly on Win32 API (essentially the
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* scheme we used in VC++ 4.0 and 4.1).
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* 09-26-97 BWT Fix POSIX
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* 09-28-98 GJF Don't initialize the small-block heap on NT 5.
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* 11-18-98 GJF Merged in VC++ 5.0 small-block heap and a selection
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* scheme from James "Triple-Expresso" MacCalman and
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* Chairman Dan Spalding.
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* 05-01-99 PML Disable small-block heap for Win64.
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* 05-13-99 PML Remove Win32s
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* 05-17-99 PML Remove all Macintosh support.
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* 06-17-99 GJF Removed old small-block heap from static libs.
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* 09-28-99 PML Processing heap-select env var must not do anything
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* that uses the heap (vs7#44259). Also, check the env
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* var before checking for NT5.0 or better.
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* 03-28-01 PML Protect against GetModuleFileName overflow (vs7#231284)
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* 06-25-01 BWT Alloc heap select strings off the process heap instead of
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* the stack (ntbug: 423988)
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*
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*******************************************************************************/
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#ifdef WINHEAP
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#include <cruntime.h>
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#include <malloc.h>
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#include <stdlib.h>
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#include <winheap.h>
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HANDLE _crtheap;
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#if !defined(_NTSDK)
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/*
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* Dummy definition of _amblksiz. Included primarily so the dll will build
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* without having to change crtlib.c (there is an access function for _amblksiz
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* defined in crtlib.c).
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*/
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unsigned int _amblksiz = BYTES_PER_PARA;
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#endif
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#ifndef _WIN64
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int __active_heap;
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#ifdef CRTDLL
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void __cdecl _GetLinkerVersion(LinkerVersion * plv)
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{
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PIMAGE_DOS_HEADER pidh;
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PIMAGE_NT_HEADERS pinh;
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plv->dw = 0;
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pidh = (PIMAGE_DOS_HEADER) GetModuleHandle(NULL);
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if ( pidh->e_magic != IMAGE_DOS_SIGNATURE || pidh->e_lfanew == 0)
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return;
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pinh = (PIMAGE_NT_HEADERS)(((PBYTE)pidh) + pidh->e_lfanew);
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plv->bverMajor = pinh->OptionalHeader.MajorLinkerVersion;
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plv->bverMinor = pinh->OptionalHeader.MinorLinkerVersion;
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}
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#endif /* CRTDLL */
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/***
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*__heap_select() - Choose from the V6, V5 or system heaps
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*
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*Purpose:
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* Check OS, environment and build bits to determine appropriate
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* small-block heap for the app.
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*
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*Entry:
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* <void>
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*Exit:
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* Returns __V6_HEAP, __V5_HEAP or __SYSTEM_HEAP
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*
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*Exceptions:
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* none
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*
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*******************************************************************************/
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int __cdecl __heap_select(void)
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{
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char *env_heap_type = NULL;
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#ifdef CRTDLL
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DWORD HeapStringSize;
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char *cp, *env_heap_select_string = NULL;
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int heap_choice;
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LinkerVersion lv;
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#endif /* CRTDLL */
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#ifdef CRTDLL
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// First, check the environment variable override
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if (HeapStringSize = GetEnvironmentVariableA(__HEAP_ENV_STRING, env_heap_select_string, 0))
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{
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env_heap_select_string = HeapAlloc(GetProcessHeap(), 0, HeapStringSize);
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if (env_heap_select_string)
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{
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if (GetEnvironmentVariableA(__HEAP_ENV_STRING, env_heap_select_string, HeapStringSize))
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{
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for (cp = env_heap_select_string; *cp; ++cp)
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if ('a' <= *cp && *cp <= 'z')
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*cp += 'A' - 'a';
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if (!strncmp(__GLOBAL_HEAP_SELECTOR,env_heap_select_string,sizeof(__GLOBAL_HEAP_SELECTOR)-1))
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env_heap_type = env_heap_select_string;
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else
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{
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char *env_app_name = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, MAX_PATH+1);
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if (env_app_name) {
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GetModuleFileName(NULL,env_app_name,sizeof(env_app_name)-1);
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for (cp = env_app_name; *cp; ++cp)
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if ('a' <= *cp && *cp <= 'z')
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*cp += 'A' - 'a';
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env_heap_type = strstr(env_heap_select_string,env_app_name);
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HeapFree(GetProcessHeap(), 0, env_app_name);
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}
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}
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if (env_heap_type)
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{
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if (env_heap_type = strchr(env_heap_type,','))
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{
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// Convert ASCII heap code to integer inline, since
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// strtol would try to use the heap (for locale info).
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cp = ++env_heap_type;
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while (*cp == ' ')
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++cp;
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heap_choice = 0;
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while (*cp >= '0' && *cp <= '9')
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heap_choice = heap_choice * 10 + *cp++ - '0';
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if ( (heap_choice == __V5_HEAP) ||
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(heap_choice == __V6_HEAP) ||
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(heap_choice == __SYSTEM_HEAP) )
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{
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HeapFree(GetProcessHeap(), 0, env_heap_select_string);
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return heap_choice;
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}
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}
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}
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}
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HeapFree(GetProcessHeap(), 0, env_heap_select_string);
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}
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}
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#endif /* CRTDLL */
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// Second, check the OS for NT >= 5.0
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if ( (_osplatform == VER_PLATFORM_WIN32_NT) && (_winmajor >= 5) )
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return __SYSTEM_HEAP;
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#ifdef CRTDLL
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// Third, check the build bits in the app; apps built with tools >= VC++ 6.0
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// will get the V6 heap, apps built with older tools will get the V5 heap
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_GetLinkerVersion(&lv);
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if (lv.bverMajor >= 6)
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return __V6_HEAP;
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else
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return __V5_HEAP;
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#else /* ndef CRTDLL */
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return __V6_HEAP;
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#endif /* CRTDLL */
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}
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#endif /* ndef _WIN64 */
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/***
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*_heap_init() - Initialize the heap
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*
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*Purpose:
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* Setup the initial C library heap.
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*
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* NOTES:
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* (1) This routine should only be called once!
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* (2) This routine must be called before any other heap requests.
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*
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*Entry:
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* <void>
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*Exit:
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* Returns 1 if successful, 0 otherwise.
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*
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*Exceptions:
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* If heap cannot be initialized, the program will be terminated
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* with a fatal runtime error.
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*
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*******************************************************************************/
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int __cdecl _heap_init (
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int mtflag
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)
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{
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#ifdef _POSIX_
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_crtheap = GetProcessHeap();
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#else
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// Initialize the "big-block" heap first.
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if ( (_crtheap = HeapCreate( mtflag ? 0 : HEAP_NO_SERIALIZE,
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BYTES_PER_PAGE, 0 )) == NULL )
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return 0;
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#ifndef _WIN64
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// Pick a heap, any heap
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__active_heap = __heap_select();
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if ( __active_heap == __V6_HEAP )
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{
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// Initialize the small-block heap
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if (__sbh_heap_init(MAX_ALLOC_DATA_SIZE) == 0)
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{
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HeapDestroy(_crtheap);
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return 0;
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}
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}
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#ifdef CRTDLL
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else if ( __active_heap == __V5_HEAP )
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{
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if ( __old_sbh_new_region() == NULL )
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{
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HeapDestroy( _crtheap );
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return 0;
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}
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}
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#endif /* CRTDLL */
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#endif /* _ndef _WIN64 */
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#endif /* _POSIX_ */
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return 1;
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}
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/***
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*_heap_term() - return the heap to the OS
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*
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*Purpose:
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*
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* NOTES:
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* (1) This routine should only be called once!
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* (2) This routine must be called AFTER any other heap requests.
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*
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*Entry:
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* <void>
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*Exit:
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* <void>
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*
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*Exceptions:
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*
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*******************************************************************************/
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void __cdecl _heap_term (void)
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{
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#ifndef _POSIX_
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#ifndef _WIN64
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// if it has been initialized, destroy the small-block heap
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if ( __active_heap == __V6_HEAP )
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{
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PHEADER pHeader = __sbh_pHeaderList;
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int cntHeader;
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// scan through all the headers
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for (cntHeader = 0; cntHeader < __sbh_cntHeaderList; cntHeader++)
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{
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// decommit and release the address space for the region
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VirtualFree(pHeader->pHeapData, BYTES_PER_REGION, MEM_DECOMMIT);
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VirtualFree(pHeader->pHeapData, 0, MEM_RELEASE);
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// free the region data structure
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HeapFree(_crtheap, 0, pHeader->pRegion);
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pHeader++;
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}
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// free the header list
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HeapFree(_crtheap, 0, __sbh_pHeaderList);
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}
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#ifdef CRTDLL
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else if ( __active_heap == __V5_HEAP )
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{
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__old_sbh_region_t *preg = &__old_small_block_heap;
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// Release the regions of the small-block heap
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do
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{
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if ( preg->p_pages_begin != NULL )
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VirtualFree( preg->p_pages_begin, 0, MEM_RELEASE );
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}
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while ( (preg = preg->p_next_region) != &__old_small_block_heap );
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}
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#endif /* CRTDLL */
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#endif /* ndef _WIN64 */
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// destroy the large-block heap
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HeapDestroy(_crtheap);
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#endif /* _POSIX_ */
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}
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#else /* ndef WINHEAP */
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#include <cruntime.h>
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#include <oscalls.h>
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#include <dos.h>
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#include <heap.h>
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#include <stddef.h>
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#include <stdio.h>
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#include <stdlib.h>
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|
/*
|
||
|
|
* Heap descriptor
|
||
|
|
*/
|
||
|
|
|
||
|
|
struct _heap_desc_ _heap_desc = {
|
||
|
|
&_heap_desc.sentinel, /* pfirstdesc */
|
||
|
|
&_heap_desc.sentinel, /* proverdesc */
|
||
|
|
NULL, /* emptylist */
|
||
|
|
NULL, /* sentinel.pnextdesc */
|
||
|
|
NULL /* sentinel.pblock */
|
||
|
|
};
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Array of region structures
|
||
|
|
* [Note: We count on the fact that this is always initialized to zero
|
||
|
|
* by the compiler.]
|
||
|
|
*/
|
||
|
|
|
||
|
|
struct _heap_region_ _heap_regions[_HEAP_REGIONMAX];
|
||
|
|
|
||
|
|
void ** _heap_descpages; /* linked list of pages used for descriptors */
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Control parameter locations
|
||
|
|
*/
|
||
|
|
|
||
|
|
unsigned int _heap_resetsize = 0xffffffff;
|
||
|
|
|
||
|
|
/* NOTE: Currenlty, _heap_growsize is a #define to _amblksiz */
|
||
|
|
unsigned int _heap_growsize = _HEAP_GROWSIZE; /* region inc size */
|
||
|
|
unsigned int _heap_regionsize = _HEAP_REGIONSIZE_L; /* region size */
|
||
|
|
unsigned int _heap_maxregsize = _HEAP_MAXREGSIZE_L; /* max region size */
|
||
|
|
|
||
|
|
/***
|
||
|
|
*_heap_init() - Initialize the heap
|
||
|
|
*
|
||
|
|
*Purpose:
|
||
|
|
* Setup the initial C library heap. All necessary memory and
|
||
|
|
* data bases are init'd appropriately so future requests work
|
||
|
|
* correctly.
|
||
|
|
*
|
||
|
|
* NOTES:
|
||
|
|
* (1) This routine should only be called once!
|
||
|
|
* (2) This routine must be called before any other heap requests.
|
||
|
|
*
|
||
|
|
*
|
||
|
|
*Entry:
|
||
|
|
* <void>
|
||
|
|
*Exit:
|
||
|
|
* <void>
|
||
|
|
*
|
||
|
|
*Exceptions:
|
||
|
|
* If heap cannot be initialized, the program will be terminated
|
||
|
|
* with a fatal runtime error.
|
||
|
|
*
|
||
|
|
*******************************************************************************/
|
||
|
|
|
||
|
|
void __cdecl _heap_init (
|
||
|
|
void
|
||
|
|
)
|
||
|
|
{
|
||
|
|
/*
|
||
|
|
* Test for Win32S or Phar Lap TNT environment
|
||
|
|
* which cannot allocate uncommitted memory
|
||
|
|
* without actually allocating physical memory
|
||
|
|
*
|
||
|
|
* High bit of _osver is set for both of those environments
|
||
|
|
* -AND- the Windows version will be less than 4.0.
|
||
|
|
*/
|
||
|
|
|
||
|
|
if ( ( _osver & 0x8000 ) && ( _winmajor < 4 ) )
|
||
|
|
{
|
||
|
|
_heap_regionsize = _HEAP_REGIONSIZE_S;
|
||
|
|
_heap_maxregsize = _HEAP_MAXREGSIZE_S;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
/***
|
||
|
|
*_heap_term() - Clean-up the heap
|
||
|
|
*
|
||
|
|
*Purpose:
|
||
|
|
* This routine will decommit and release ALL of the CRT heap.
|
||
|
|
* All memory malloc-ed by the CRT will then be invalid.
|
||
|
|
*
|
||
|
|
* NOTES:
|
||
|
|
* (1) This routine should only be called once!
|
||
|
|
* (2) This routine must be called AFTER any other heap requests.
|
||
|
|
*
|
||
|
|
*Entry:
|
||
|
|
* <void>
|
||
|
|
*Exit:
|
||
|
|
* <void>
|
||
|
|
*
|
||
|
|
*Exceptions:
|
||
|
|
*
|
||
|
|
*******************************************************************************/
|
||
|
|
|
||
|
|
void __cdecl _heap_term (
|
||
|
|
void
|
||
|
|
)
|
||
|
|
{
|
||
|
|
int index;
|
||
|
|
void **pageptr;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Loop through the region descriptor table, decommitting
|
||
|
|
* and releasing (freeing up) each region that is in use.
|
||
|
|
*/
|
||
|
|
|
||
|
|
for ( index=0 ; index < _HEAP_REGIONMAX ; index++ ) {
|
||
|
|
void * regbase ;
|
||
|
|
|
||
|
|
if ( (regbase = _heap_regions[index]._regbase)
|
||
|
|
&& VirtualFree(regbase, _heap_regions[index]._currsize, MEM_DECOMMIT)
|
||
|
|
&& VirtualFree(regbase, 0, MEM_RELEASE) )
|
||
|
|
regbase = _heap_regions[index]._regbase = NULL ;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Now we need to decommit and release the pages used for descriptors
|
||
|
|
* _heap_descpages points to the head of a singly-linked list of the pages.
|
||
|
|
*/
|
||
|
|
|
||
|
|
pageptr = _heap_descpages;
|
||
|
|
|
||
|
|
while ( pageptr ) {
|
||
|
|
void **nextpage;
|
||
|
|
|
||
|
|
nextpage = *pageptr;
|
||
|
|
|
||
|
|
if(!VirtualFree(pageptr, 0, MEM_RELEASE))
|
||
|
|
break; /* if the linked list is corrupted, give up */
|
||
|
|
|
||
|
|
pageptr = nextpage;
|
||
|
|
}
|
||
|
|
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
/***
|
||
|
|
* _heap_grow_emptylist() - Grow the empty heap descriptor list
|
||
|
|
*
|
||
|
|
*Purpose:
|
||
|
|
* (1) Get memory from OS
|
||
|
|
* (2) Form it into a linked list of empty heap descriptors
|
||
|
|
* (3) Attach it to the master empty list
|
||
|
|
*
|
||
|
|
* NOTE: This routine assumes that the emptylist is NULL
|
||
|
|
* when called (i.e., there are no available empty heap descriptors).
|
||
|
|
*
|
||
|
|
*Entry:
|
||
|
|
* (void)
|
||
|
|
*
|
||
|
|
*Exit:
|
||
|
|
* 1, if the empty heap descriptor list was grown
|
||
|
|
* 0, if the empty heap descriptor list could not be grown.
|
||
|
|
*
|
||
|
|
*Exceptions:
|
||
|
|
*
|
||
|
|
*******************************************************************************/
|
||
|
|
|
||
|
|
static int __cdecl _heap_grow_emptylist (
|
||
|
|
void
|
||
|
|
)
|
||
|
|
{
|
||
|
|
REG1 _PBLKDESC first;
|
||
|
|
REG2 _PBLKDESC next;
|
||
|
|
_PBLKDESC last;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Get memory for the new empty heap descriptors
|
||
|
|
*
|
||
|
|
* Note that last is used to hold the returned pointer because
|
||
|
|
* first (and next) are register class.
|
||
|
|
*/
|
||
|
|
|
||
|
|
if ( !(last = VirtualAlloc(NULL,
|
||
|
|
_HEAP_EMPTYLIST_SIZE,
|
||
|
|
MEM_COMMIT,
|
||
|
|
PAGE_READWRITE)) )
|
||
|
|
return 0;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Add this descriptor block to the front of the list
|
||
|
|
*
|
||
|
|
* Advance "last" to skip over the
|
||
|
|
*/
|
||
|
|
|
||
|
|
*(void **)last = _heap_descpages;
|
||
|
|
_heap_descpages = (void **)(last++);
|
||
|
|
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Init the empty heap descriptor list.
|
||
|
|
*/
|
||
|
|
|
||
|
|
_heap_desc.emptylist = first = last;
|
||
|
|
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Carve the memory into an empty list
|
||
|
|
*/
|
||
|
|
|
||
|
|
last = (_PBLKDESC) ((char *) first + _HEAP_EMPTYLIST_SIZE - 2 * sizeof(_BLKDESC));
|
||
|
|
next = (_PBLKDESC) ((char *) first + sizeof(_BLKDESC));
|
||
|
|
|
||
|
|
while ( first < last ) {
|
||
|
|
|
||
|
|
/* Init this descriptor */
|
||
|
|
#ifdef DEBUG
|
||
|
|
first->pblock = NULL;
|
||
|
|
#endif
|
||
|
|
first->pnextdesc = next;
|
||
|
|
|
||
|
|
/* onto the next block */
|
||
|
|
|
||
|
|
first = next++;
|
||
|
|
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Take care of the last descriptor (end of the empty list)
|
||
|
|
*/
|
||
|
|
|
||
|
|
last->pnextdesc = NULL;
|
||
|
|
|
||
|
|
#ifdef DEBUG
|
||
|
|
last->pblock = NULL;
|
||
|
|
#endif
|
||
|
|
|
||
|
|
return 1;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
/***
|
||
|
|
*__getempty() - get an empty heap descriptor
|
||
|
|
*
|
||
|
|
*Purpose:
|
||
|
|
* Get a descriptor from the list of empty heap descriptors. If the list
|
||
|
|
* is empty, call _heap_grow_emptylist.
|
||
|
|
*
|
||
|
|
*Entry:
|
||
|
|
* no arguments
|
||
|
|
*
|
||
|
|
*Exit:
|
||
|
|
* If successful, a pointer to the descriptor is returned.
|
||
|
|
* Otherwise, NULL is returned.
|
||
|
|
*
|
||
|
|
*Exceptions:
|
||
|
|
*
|
||
|
|
*******************************************************************************/
|
||
|
|
|
||
|
|
_PBLKDESC __cdecl __getempty(
|
||
|
|
void
|
||
|
|
)
|
||
|
|
{
|
||
|
|
_PBLKDESC pdesc;
|
||
|
|
|
||
|
|
if ( (_heap_desc.emptylist == NULL) && (_heap_grow_emptylist()
|
||
|
|
== 0) )
|
||
|
|
return NULL;
|
||
|
|
|
||
|
|
pdesc = _heap_desc.emptylist;
|
||
|
|
|
||
|
|
_heap_desc.emptylist = pdesc->pnextdesc;
|
||
|
|
|
||
|
|
return pdesc;
|
||
|
|
}
|
||
|
|
|
||
|
|
#endif /* WINHEAP */
|