urlcache.c

winNT技术操作系统,国外开放的原代码和LIUX一样

			    }
			    else if (j >= 255)
			    {
				/* Give up. The most likely cause of this
				 * is a full disk, but whatever the cause
				 * is, it should be more than apparent that
				 * we won't succeed.
				 */
				dwError = GetLastError();
				break;
			    }
			}
		    }
		
		    UnmapViewOfFile(pHeader);
		}
		else
		{
		    dwError = GetLastError();
		}
		CloseHandle(hMapping);
	    }
	    else
	    {
		dwError = GetLastError();
	    }
	}

	if (dwError)
	{
	    CloseHandle(hFile);
	    DeleteFileW(wszFilePath);
	    ReleaseMutex(pContainer->hMutex);
	    SetLastError(dwError);
	    return FALSE;
	}

    }

    ReleaseMutex(pContainer->hMutex);

    wsprintfW(wszFilePath, wszMappingFormat, pContainer->path, wszIndex, dwFileSize);
    URLCache_PathToObjectName(wszFilePath, '_');
    pContainer->hMapping = OpenFileMappingW(FILE_MAP_WRITE, FALSE, wszFilePath);
    if (!pContainer->hMapping)
        pContainer->hMapping = CreateFileMappingW(hFile, NULL, PAGE_READWRITE, 0, 0, wszFilePath);
    CloseHandle(hFile);
    if (!pContainer->hMapping)
    {
        ERR("Couldn't create file mapping (error is %ld)\n", GetLastError());
        return FALSE;
    }

    return TRUE;
}

/***********************************************************************
 *           URLCacheContainer_CloseIndex (Internal)
 *
 *  Closes the index
 *
 * RETURNS
 *    nothing
 *
 */
static void URLCacheContainer_CloseIndex(URLCACHECONTAINER * pContainer)
{
    CloseHandle(pContainer->hMapping);
    pContainer->hMapping = NULL;
}

static BOOL URLCacheContainers_AddContainer(LPCWSTR cache_prefix, LPCWSTR path, LPWSTR mutex_name)
{
    URLCACHECONTAINER * pContainer = HeapAlloc(GetProcessHeap(), 0, sizeof(URLCACHECONTAINER));
    int path_len = strlenW(path);
    int cache_prefix_len = strlenW(cache_prefix);

    if (!pContainer)
    {
        return FALSE;
    }

    pContainer->hMapping = NULL;
    pContainer->file_size = 0;

    pContainer->path = HeapAlloc(GetProcessHeap(), 0, (path_len + 1) * sizeof(WCHAR));
    if (!pContainer->path)
    {
        HeapFree(GetProcessHeap(), 0, pContainer);
        return FALSE;
    }

    memcpy(pContainer->path, path, (path_len + 1) * sizeof(WCHAR));

    pContainer->cache_prefix = HeapAlloc(GetProcessHeap(), 0, (cache_prefix_len + 1) * sizeof(WCHAR));
    if (!pContainer->cache_prefix)
    {
        HeapFree(GetProcessHeap(), 0, pContainer->path);
        HeapFree(GetProcessHeap(), 0, pContainer);
        return FALSE;
    }

    memcpy(pContainer->cache_prefix, cache_prefix, (cache_prefix_len + 1) * sizeof(WCHAR));

    CharLowerW(mutex_name);
    URLCache_PathToObjectName(mutex_name, '!');

    if ((pContainer->hMutex = CreateMutexW(NULL, FALSE, mutex_name)) == NULL)
    {
        ERR("couldn't create mutex (error is %ld)\n", GetLastError());
        HeapFree(GetProcessHeap(), 0, pContainer->path);
        HeapFree(GetProcessHeap(), 0, pContainer);
        return FALSE;
    }

    list_add_head(&UrlContainers, &pContainer->entry);

    return TRUE;
}

static void URLCacheContainer_DeleteContainer(URLCACHECONTAINER * pContainer)
{
    list_remove(&pContainer->entry);

    URLCacheContainer_CloseIndex(pContainer);
    CloseHandle(pContainer->hMutex);
    HeapFree(GetProcessHeap(), 0, pContainer->path);
    HeapFree(GetProcessHeap(), 0, pContainer->cache_prefix);
    HeapFree(GetProcessHeap(), 0, pContainer);
}

void URLCacheContainers_CreateDefaults(void)
{
    static const WCHAR UrlSuffix[] = {'C','o','n','t','e','n','t','.','I','E','5',0};
    static const WCHAR UrlPrefix[] = {0};
    static const WCHAR HistorySuffix[] = {'H','i','s','t','o','r','y','.','I','E','5',0};
    static const WCHAR HistoryPrefix[] = {'V','i','s','i','t','e','d',':',0};
    static const WCHAR CookieSuffix[] = {0};
    static const WCHAR CookiePrefix[] = {'C','o','o','k','i','e',':',0};
    static const struct
    {
        int nFolder; /* CSIDL_* constant */
        const WCHAR * shpath_suffix; /* suffix on path returned by SHGetSpecialFolderPath */
        const WCHAR * cache_prefix; /* prefix used to reference the container */
    } DefaultContainerData[] = 
    {
        { CSIDL_INTERNET_CACHE, UrlSuffix, UrlPrefix },
        { CSIDL_HISTORY, HistorySuffix, HistoryPrefix },
        { CSIDL_COOKIES, CookieSuffix, CookiePrefix },
    };
    DWORD i;

    for (i = 0; i < sizeof(DefaultContainerData) / sizeof(DefaultContainerData[0]); i++)
    {
        WCHAR wszCachePath[MAX_PATH];
        WCHAR wszMutexName[MAX_PATH];
        int path_len, suffix_len;

        if (FAILED(SHGetSpecialFolderPathW(NULL, wszCachePath, DefaultContainerData[i].nFolder, TRUE)))
        {
            ERR("Couldn't get path for default container %lu\n", i);
            continue;
        }
        path_len = strlenW(wszCachePath);
        suffix_len = strlenW(DefaultContainerData[i].shpath_suffix);

        if (path_len + suffix_len + 2 > MAX_PATH)
        {
            ERR("Path too long\n");
            continue;
        }

        wszCachePath[path_len] = '\\';

        strcpyW(wszMutexName, wszCachePath);
        
        if (suffix_len)
        {
            memcpy(wszCachePath + path_len + 1, DefaultContainerData[i].shpath_suffix, (suffix_len + 1) * sizeof(WCHAR));
            wszCachePath[path_len + suffix_len + 1] = '\\';
            wszCachePath[path_len + suffix_len + 2] = '\0';
        }

        URLCacheContainers_AddContainer(DefaultContainerData[i].cache_prefix, wszCachePath, wszMutexName);
    }
}

void URLCacheContainers_DeleteAll(void)
{
    while(!list_empty(&UrlContainers))
        URLCacheContainer_DeleteContainer(
            LIST_ENTRY(list_head(&UrlContainers), URLCACHECONTAINER, entry)
        );
}

static BOOL URLCacheContainers_FindContainerW(LPCWSTR lpwszUrl, URLCACHECONTAINER ** ppContainer)
{
    struct list * cursor;

    TRACE("searching for prefix for URL: %s\n", debugstr_w(lpwszUrl));

    LIST_FOR_EACH(cursor, &UrlContainers)
    {
        URLCACHECONTAINER * pContainer = LIST_ENTRY(cursor, URLCACHECONTAINER, entry);
        int prefix_len = strlenW(pContainer->cache_prefix);
        if (!strncmpW(pContainer->cache_prefix, lpwszUrl, prefix_len))
        {
            TRACE("found container with prefx %s for URL %s\n", debugstr_w(pContainer->cache_prefix), debugstr_w(lpwszUrl));
            *ppContainer = pContainer;
            return TRUE;
        }
    }
    ERR("no container found\n");
    SetLastError(ERROR_FILE_NOT_FOUND);
    return FALSE;
}

static BOOL URLCacheContainers_FindContainerA(LPCSTR lpszUrl, URLCACHECONTAINER ** ppContainer)
{
    BOOL ret;
    LPWSTR lpwszUrl;
    int url_len = MultiByteToWideChar(CP_ACP, 0, lpszUrl, -1, NULL, 0);
    if (url_len && (lpwszUrl = HeapAlloc(GetProcessHeap(), 0, url_len * sizeof(WCHAR))))
    {
        MultiByteToWideChar(CP_ACP, 0, lpszUrl, -1, lpwszUrl, url_len);
        ret = URLCacheContainers_FindContainerW(lpwszUrl, ppContainer);
        HeapFree(GetProcessHeap(), 0, lpwszUrl);
        return ret;
    }
    return FALSE;
}

/***********************************************************************
 *           URLCacheContainer_LockIndex (Internal)
 *
 */
static LPURLCACHE_HEADER URLCacheContainer_LockIndex(URLCACHECONTAINER * pContainer)
{
    BYTE index;
    LPVOID pIndexData;
    URLCACHE_HEADER * pHeader;

    /* acquire mutex */
    WaitForSingleObject(pContainer->hMutex, INFINITE);

    pIndexData = MapViewOfFile(pContainer->hMapping, FILE_MAP_WRITE, 0, 0, 0);

    if (!pIndexData)
    {
        ReleaseMutex(pContainer->hMutex);
        ERR("Couldn't MapViewOfFile. Error: %ld\n", GetLastError());
        return FALSE;
    }
    pHeader = (URLCACHE_HEADER *)pIndexData;

    /* file has grown - we need to remap to prevent us getting
     * access violations when we try and access beyond the end
     * of the memory mapped file */
    if (pHeader->dwFileSize != pContainer->file_size)
    {
        URLCacheContainer_CloseIndex(pContainer);
        if (!URLCacheContainer_OpenIndex(pContainer))
        {
            ReleaseMutex(pContainer->hMutex);
            return FALSE;
        }
        pIndexData = MapViewOfFile(pContainer->hMapping, FILE_MAP_WRITE, 0, 0, 0);

        if (!pIndexData)
        {
            ReleaseMutex(pContainer->hMutex);
            ERR("Couldn't MapViewOfFile. Error: %ld\n", GetLastError());
            return FALSE;
        }
        pHeader = (URLCACHE_HEADER *)pIndexData;
    }

    TRACE("Signature: %s, file size: %ld bytes\n", pHeader->szSignature, pHeader->dwFileSize);

    for (index = 0; index < pHeader->DirectoryCount; index++)
    {
        TRACE("Directory[%d] = \"%.8s\"\n", index, pHeader->directory_data[index].filename);
    }
    
    return pHeader;
}

/***********************************************************************
 *           URLCacheContainer_UnlockIndex (Internal)
 *
 */
static BOOL URLCacheContainer_UnlockIndex(URLCACHECONTAINER * pContainer, LPURLCACHE_HEADER pHeader)
{
    /* release mutex */
    ReleaseMutex(pContainer->hMutex);
    return UnmapViewOfFile(pHeader);
}


#ifndef CHAR_BIT
#define CHAR_BIT    (8 * sizeof(CHAR))
#endif

/***********************************************************************
 *           URLCache_Allocation_BlockIsFree (Internal)
 *
 *  Is the specified block number free?
 *
 * RETURNS
 *    zero if free
 *    non-zero otherwise
 *
 */
static inline BYTE URLCache_Allocation_BlockIsFree(BYTE * AllocationTable, DWORD dwBlockNumber)
{
    BYTE mask = 1 << (dwBlockNumber % CHAR_BIT);
    return (AllocationTable[dwBlockNumber / CHAR_BIT] & mask) == 0;
}

/***********************************************************************
 *           URLCache_Allocation_BlockFree (Internal)
 *
 *  Marks the specified block as free
 *
 * RETURNS
 *    nothing
 *
 */
static inline void URLCache_Allocation_BlockFree(BYTE * AllocationTable, DWORD dwBlockNumber)
{
    BYTE mask = ~(1 << (dwBlockNumber % CHAR_BIT));
    AllocationTable[dwBlockNumber / CHAR_BIT] &= mask;
}

/***********************************************************************
 *           URLCache_Allocation_BlockAllocate (Internal)
 *
 *  Marks the specified block as allocated
 *
 * RETURNS
 *    nothing
 *
 */
static inline void URLCache_Allocation_BlockAllocate(BYTE * AllocationTable, DWORD dwBlockNumber)
{
    BYTE mask = 1 << (dwBlockNumber % CHAR_BIT);
    AllocationTable[dwBlockNumber / CHAR_BIT] |= mask;
}

/***********************************************************************
 *           URLCache_FindFirstFreeEntry (Internal)
 *
 *  Finds and allocates the first block of free space big enough and
 * sets ppEntry to point to it.
 *
 * RETURNS
 *    TRUE if it had enough space
 *    FALSE if it couldn't find enough space
 *
 */
static BOOL URLCache_FindFirstFreeEntry(URLCACHE_HEADER * pHeader, DWORD dwBlocksNeeded, CACHEFILE_ENTRY ** ppEntry)
{
    LPBYTE AllocationTable = (LPBYTE)pHeader + ALLOCATION_TABLE_OFFSET;
    DWORD dwBlockNumber;
    DWORD dwFreeCounter;
    for (dwBlockNumber = 0; dwBlockNumber < pHeader->dwIndexCapacityInBlocks; dwBlockNumber++)
    {
        for (dwFreeCounter = 0; 
            dwFreeCounter < dwBlocksNeeded &&
              dwFreeCounter + dwBlockNumber < pHeader->dwIndexCapacityInBlocks &&
              URLCache_Allocation_BlockIsFree(AllocationTable, dwBlockNumber + dwFreeCounter);
            dwFreeCounter++)
                TRACE("Found free block at no. %ld (0x%lx)\n", dwBlockNumber, ENTRY_START_OFFSET + dwBlockNumber * BLOCKSIZE);

        if (dwFreeCounter == dwBlocksNeeded)
        {
            DWORD index;
            TRACE("Found free blocks starting at no. %ld (0x%lx)\n", dwBlockNumber, ENTRY_START_OFFSET + dwBlockNumber * BLOCKSIZE);
            for (index = 0; index < dwBlocksNeeded; index++)
                URLCache_Allocation_BlockAllocate(AllocationTable, dwBlockNumber + index);
            *ppEntry = (CACHEFILE_ENTRY *)((LPBYTE)pHeader + ENTRY_START_OFFSET + dwBlockNumber * BLOCKSIZE);
            (*ppEntry)->dwBlocksUsed = dwBlocksNeeded;
            return TRUE;
        }
    }
    FIXME("Grow file\n");
    return FALSE;
}