dosfslib.c

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#endif	/* _BYTE_ORDER == _BIG_ENDIAN */

/* Macros to set and get inode numbers for DOS files (used by NFS) */

				/* Get a cluster number from an inode # */
#define INODE_TO_CLUSTER(x) ((x) & 0x0000ffff)
				/* Get a generation number from an inode # */
#define INODE_TO_GENERATION(x) (((x) >> 16) & 0x0000ffff)

				/* Get a generation number from a dir entry */
#define GENERATION_GET(pDirEnt) (*((int *) & ((pDirEnt)->dosde_reserved)) \
				 & 0x0000ffff)

				/* Set a generation number for a dir entry */
#define GENERATION_SET(pDirEnt, newVal) (*((int *) ((pDirEnt)->dosde_reserved))\
					 = ((newVal) & 0x0000ffff))

/* to turn off warnings related to local implementation of malloc() etc. */

#define	malloc	malloc_lfn
#define	calloc	calloc_lfn
#define	free	free_lfn

/* DATA STRUCTURES */

/* dosFs file descriptor */

typedef struct		/* DOS_FILE_DESC */
    {
    NODE	dosfd_node;		/* linked list node info */
    SEM_ID	dosfd_semId;		/* semaphore for this file descriptor */
    short	dosfd_status;		/* file descriptor status (see below) */
    DOS_VOL_DESC *dosfd_vdptr;		/* ptr to dosFs volume descriptor */
    int		dosfd_cluster;		/* number of first cluster in file */
    short	dosfd_mode;		/* mode: O_RDONLY, O_WRONLY, O_RDWR */
    DOS_DIR_ENT	*dosfd_pDirEnt;		/* ptr to dir entry for this file */
    UINT	dosfd_curptr;		/* file byte ptr of I/O buffer byte 0 */
    UINT	dosfd_newptr;		/* file byte ptr for new read/writes */
    UINT	dosfd_endptr;		/* file byte ptr to end of file */
    BOOL	dosfd_rawMode;		/* TRUE = Fd describes raw disk */
    BOOL	dosfd_contig;		/* TRUE = contiguous file */
    BOOL	dosfd_modified;		/* TRUE = buffer has been modified */
    BOOL	dosfd_changed;		/* TRUE = file modified while open */
    char	*dosfd_buffer;		/* pointer to read/write buffer area */
    int		dosfd_bufClust;		/* number of cluster in I/O buffer */
    int		dosfd_bufSec;		/* number of sector in buffer (root) */
    } DOS_FILE_DESC;


/* File descriptor status values */

#define DOSFD_AVAILABLE		-1	/* file descriptor available */
#define DOSFD_IN_USE		0	/* file descriptor in-use */
#define DOSFD_OBSOLETE		1	/* file descriptor obsolete */
#define DOSFD_DELETED		2	/* file or dir was deleted while open */



/* GLOBALS */


int	dosFsDrvNum = ERROR;	  /* driver number assigned to dosFsLib */
char	*dosFsSysId = "VXDOS4.0"; /* ID put in boot sector during formatting */
char	*dosFsExtSysId = "VXEXT1.0"; /* ID string if using extended names */

					/* default mutex options */
int	dosFsVolMutexOptions    = (SEM_Q_PRIORITY | SEM_DELETE_SAFE);
int	dosFsFdListMutexOptions = (SEM_Q_PRIORITY | SEM_DELETE_SAFE);
int	dosFsFdMutexOptions     = (SEM_Q_PRIORITY | SEM_DELETE_SAFE);
int     dosFsUserId             = 65534; /* owner id for files */
int     dosFsGroupId            = 65534;
int     dosFsFileMode           = DOS_DEFAULT_MODE;
int     dosFsHashTblSize        = DOS_DEFAULT_HASH_SIZE; /* size of hashtable */


int	dosFsClustInitBytesMax	= 0x4000;	/* max buffer during clustInit*/


/* The following are used in dosFsLib's internal memory management.
 * dosFsMemPartIdOptions is used to initialize the error handling
 * strategy employed by memPartLib.  dosFsMemPartInitSize sets the
 * starting size of the dosFs memory pool. dosFsMemPartGrowSize is used
 * to set the minimum size dosFs will grow the pool by when allocation
 * errors occur. Both dosFsMemPartInitSize and dosFsMemPartGrowSize are
 * adjusted for memPartLib internal overhead. The global dosFsMemPartCap
 * is used to limit how large dosFsMemPart is alowed to grow, in bytes. 
 * -1 means no cap limit.
 */

PART_ID	dosFsMemPartId	= NULL ;	/* where to get memory */
UINT    dosFsMemPartIdOptions = MEM_BLOCK_ERROR_LOG_FLAG;  /* SPR22406 */
						/* only log free errors */
int	dosFsMemPartInitSize = 8*1024;		/* start with 8 k */
int	dosFsMemPartGrowSize = 4 * 1024;	/* add this on failures */
UINT	dosFsMemPartCap      = -1;		/* no cap */

/* LOCALS */

LOCAL FUNCPTR 		dosDateTimeFunc = NULL;	/* user's date/time routine */
LOCAL LIST		dosFsFdActiveList;	/* linked list of in-use Fd's */
LOCAL LIST		dosFsFdFreeList;	/* linked list of avail. Fd's */
LOCAL SEM_ID 		dosFsFdSemId;		/* file descr list semaphore  */

LOCAL UINT		dosFsMkfsOptions = DEFAULT_OPTIONS;	
						/* options to use during mkfs */
LOCAL UINT		dosFsDevInitOptions = DEFAULT_OPTIONS;
						/* options during devInit */

LOCAL char		*pDotPadded    = DOT_PADDED;
LOCAL char		*pDotDotPadded = DOTDOT_PADDED;

LOCAL DOS_DATE_TIME	dosFsDateTime =
			{
			1980,			/* year, default = 1980       */
			1,			/* month, default = 1 (Jan.)  */
			1,			/* day, default = 1           */
			0,			/* hour, default is 0         */
			0,			/* minute, default is 0       */
			0			/* second, default is 0       */
			};



/* forward LOCAL functions */

LOCAL STATUS dosFsClose (DOS_FILE_DESC *pDosFd);
LOCAL int dosFsClustAdd (DOS_VOL_DESC *vdptr, int curClust);
LOCAL void dosFsClustChainFree (DOS_VOL_DESC *vdptr, int cluster);
LOCAL int dosFsClustContigCnt (DOS_VOL_DESC *vdptr, int startClust);
LOCAL int dosFsClustContigFind (DOS_VOL_DESC *vdptr, int totalClusts, 
				int initClust);
LOCAL int dosFsClustContigMax (DOS_VOL_DESC *vdptr, UINT *pCount,int initClust);
LOCAL int dosFsClustFind (DOS_FILE_DESC *pDosFd, int startClust, 
			  int clustOffset, BOOL doAlloc, BOOL doInit);
LOCAL void dosFsClustFree (DOS_VOL_DESC *vdptr, int cluster);
LOCAL int dosFsClustGet (DOS_VOL_DESC *vdptr, int curClust);
LOCAL STATUS dosFsClustInit (DOS_VOL_DESC * vdptr, int startClust,
			     int numClusts);
LOCAL int dosFsClustNew (DOS_FILE_DESC *pDosFd, int access);
LOCAL int dosFsClustNext (DOS_VOL_DESC *vdptr, int cluster);
LOCAL STATUS dosFsClustRd (DOS_VOL_DESC *vdptr, int startClust, int numClusts, 
			   char *pBuf);
LOCAL STATUS dosFsClustWrt (DOS_VOL_DESC *vdptr, int startClust, 
			    int numClusts, char *pBuf);
LOCAL DOS_FILE_DESC *dosFsCreate (DOS_VOL_DESC *vdptr, char *fullName, 
				  int flags);
LOCAL int dosFsDate (int year, int month, int day);
LOCAL void dosFsDateTimeFill (DOS_DIR_ENT *pDirEnt);
LOCAL STATUS dosFsDelete (DOS_VOL_DESC *vdptr, char *name);
LOCAL BOOL dosFsFileCmp (DOS_DIR_ENT * entry1, DOS_DIR_ENT * entry2);
LOCAL int dosFsInodeHash (int elements, DOS_DIR_ENT * pDirEnt, int seed);
LOCAL DOS_FILE_DESC *dosFsDirCreate (DOS_VOL_DESC *vdptr, char *name);
LOCAL STATUS dosFsDirEntAdd (DOS_VOL_DESC *vdptr, DOS_DIR_ENT *pNewEnt,
			     DOS_DIR_ENT *pParent);
LOCAL STATUS dosFsDirEntInit (DOS_DIR_ENT *pDirEnt, char *name, int clustNum, 
			      UINT8 attrib, BOOL longNames, BOOL lowerCase);
LOCAL STATUS dosFsDirFlush (DOS_VOL_DESC *vdptr, DOS_DIR_ENT *pDir);
LOCAL STATUS dosFsDirFree (DOS_VOL_DESC *vdptr, DOS_DIR_ENT *pDir);
LOCAL STATUS dosFsDirLoad (DOS_VOL_DESC *vdptr, DOS_DIR_ENT *pDir);
LOCAL DOS_DIR_ENT *dosFsDirMake (DOS_VOL_DESC *vdptr, char *name, 
				 BOOL nameExpanded);
LOCAL STATUS dosFsDirRead (DOS_FILE_DESC *pDosFd, DIR *pDir);
LOCAL void dosFsDiskEntryGet (DOS_DISK_DIR_ENT *pDiskEnt, 
			      DOS_DIR_ENT *pDirEnt, BOOL longNames);
LOCAL void dosFsDiskEntryPut (DOS_DIR_ENT *pDirEnt, DOS_DISK_DIR_ENT *pDiskEnt,
			      BOOL longNames);
LOCAL DOS_DIR_ENT *dosFsEntryFind (DOS_VOL_DESC *vdptr, char *name,
				   DOS_DIR_ENT *pParent);
LOCAL int dosFsFatEntGet (DOS_VOL_DESC *vdptr, int cluster);
LOCAL void dosFsFatEntPut (DOS_VOL_DESC *vdptr, int cluster, int value);
LOCAL STATUS dosFsFatFlush (DOS_VOL_DESC *vdptr);
LOCAL STATUS dosFsFatRd (DOS_VOL_DESC *vdptr);
LOCAL void dosFsFdFree (DOS_FILE_DESC *pDosFd);
LOCAL DOS_FILE_DESC *dosFsFdGet (void);
LOCAL STATUS dosFsFileAttribSet (DOS_FILE_DESC *pDosFd, UINT8 newAttrib);
LOCAL STATUS dosFsFileContigAlloc (DOS_FILE_DESC *pDosFd, int reqBytes);
LOCAL DOS_DIR_ENT *dosFsFileCreate (DOS_VOL_DESC *vdptr, DOS_FILE_DESC *pDosFd,
				    char *fullName);
LOCAL STATUS dosFsFileDelete (DOS_VOL_DESC *vdptr, char *name);
LOCAL DOS_DIR_ENT *dosFsFileFind (DOS_VOL_DESC *vdptr, char *pathName);
LOCAL STATUS dosFsFileFlush (DOS_FILE_DESC *pDosFd);
LOCAL int dosFsFileRead (DOS_FILE_DESC *pDosFd, char *pBuf, int maxBytes);
LOCAL STATUS dosFsFileStatGet (DOS_FILE_DESC *pDosFd, struct stat *pStat);
LOCAL STATUS dosFsFSStatGet (DOS_FILE_DESC *pDosFd, struct statfs *pStat);
LOCAL STATUS dosFsFileTrunc (DOS_FILE_DESC *pDosFd, int newLength);
LOCAL STATUS dosFsFlush (DOS_FILE_DESC *pDosFd);
LOCAL UINT dosFsFreeCountGet (DOS_VOL_DESC *vdptr);
LOCAL STATUS dosFsIoctl (DOS_FILE_DESC *pDosFd, int function, int arg);
LOCAL STATUS dosFsName (char *fullName, UINT8 *nameOnly, UINT8 *extOnly,
			BOOL longNames, BOOL lowerCase);
LOCAL void dosFsNameGet (char *pName, char *nameBuf, BOOL longNames);
LOCAL DOS_FILE_DESC *dosFsOpen (DOS_VOL_DESC *vdptr, char *name, int flags,
				int mode);
LOCAL int dosFsRead (DOS_FILE_DESC *pDosFd, char *pBuf, int maxBytes);
LOCAL STATUS dosFsRename (DOS_FILE_DESC *pDosFd, char *newName);
LOCAL STATUS dosFsReset (DOS_VOL_DESC *vdptr);
LOCAL STATUS dosFsSecRd (DOS_VOL_DESC *vdptr, int startSec, UINT numSecs,
			 char *pBuf);
LOCAL STATUS dosFsSecWrt (DOS_VOL_DESC *vdptr, int startSec, UINT numSecs,
			  char *pBuf);
LOCAL STATUS dosFsSeek (DOS_FILE_DESC *pDosFd, int position);
LOCAL STATUS dosFsSync (DOS_FILE_DESC *pDosFd);
LOCAL int dosFsTime (int hour, int minute, int second);
LOCAL time_t dosFsTimeDosToAnsi (USHORT dosTime, USHORT dosDate);
LOCAL USHORT dosFsTimeAnsiToDos (time_t ansiTime, USHORT * dosTime,
				 USHORT * dosDate);
LOCAL void dosFsParentTimeIncrement (DOS_DIR_ENT * pDirEnt);
LOCAL STATUS dosFsVolCheck (DOS_VOL_DESC *vdptr, BOOL doMount);
LOCAL void dosFsVolDescFill (DOS_VOL_DESC *vdptr);
LOCAL STATUS dosFsVolFlush (DOS_VOL_DESC *vdptr);
LOCAL STATUS dosFsVolInit (DOS_VOL_DESC *vdptr);
LOCAL DOS_DIR_ENT *dosFsVolLabelFind (DOS_VOL_DESC *vdptr);
LOCAL STATUS dosFsVolLabelGet (DOS_VOL_DESC *vdptr, char *pBuf);
LOCAL STATUS dosFsVolLabelSet (DOS_VOL_DESC *vdptr, char *pString);
LOCAL STATUS dosFsVolMount (DOS_VOL_DESC *vdptr);
LOCAL int dosFsWhere (DOS_FILE_DESC *pDosFd);
LOCAL int dosFsWrite (DOS_FILE_DESC *pDosFd, char *pBuf, int maxBytes);
LOCAL DOS_DIR_ENT * dosFsFindByInode (DOS_VOL_DESC * vdptr, DOS_DIR_ENT * pDir,
				      ULONG inode);
LOCAL STATUS dosFsDirentToStr (DOS_DIR_ENT * pDir, DOS_VOL_DESC * vdptr,
			       char * fileName);
LOCAL int dosFsGenerationGet (DOS_VOL_DESC * vdptr);

/*******************************************************************************
*
* malloc_lfn - local substitute for this ANSI function
*
* This local function is substantially the same as its ANSI counterpart
* except that it uses a private memory partition to manage its memory
* needs, in order to minimize fragmentation.
* If the private partition does not have sufficient free memory,
* then additional memory will be added into this partition from
* the general system partition.
*
*/
LOCAL void * malloc_lfn(size_t size )
    {
    void * ptr  ;
    size_t addSize ;

    /* mem part mutex is needed to avoid race condition */

    semTake (&dosFsMemPartId->sem, WAIT_FOREVER);	/* spr22406 */

    /* allocated, test for error and handle error - spr 22406 */


    if ( ((ptr = memPartAlloc( dosFsMemPartId, size )) == NULL ) 
       && ((UINT)( (int)(dosFsMemPartId->totalWords * 2)) < 
	  (UINT) (dosFsMemPartCap)) )

        {

	/* Add more memory to private partition; alloc from 
	 * sysMemPool, add to ours, and handle errors.
	 */

	addSize = max( size + 64, dosFsMemPartGrowSize + 64 );
	ptr = memPartAlloc( memSysPartId, addSize );

	if( ptr != NULL )
	    {
	    if( memPartAddToPool( dosFsMemPartId, ptr, addSize ) != ERROR )
		{
		if ((ptr = memPartAlloc( dosFsMemPartId, size )) != NULL)
		     errno = OK;
		}
	    else
		{
		memPartFree( memSysPartId, ptr );
		ptr = NULL ;
		}
	    }
	}

    semGive (&dosFsMemPartId->sem);			/* spr22406 */
    return( ptr );
    }


/************************