xnu-2050.7.9.tar.gz

[apple/xnu.git] / bsd / hfs / hfscommon / Misc / FileExtentMapping.c

diff --git a/bsd/hfs/hfscommon/Misc/FileExtentMapping.c b/bsd/hfs/hfscommon/Misc/FileExtentMapping.c
index 998f97fa930b04bf808cd011b091c16ec0b80988..cae3db8e2a602f39cbd295fbf9ff581447982a8d 100644 (file)
--- a/bsd/hfs/hfscommon/Misc/FileExtentMapping.c
+++ b/bsd/hfs/hfscommon/Misc/FileExtentMapping.c
@@ -225,7 +225,7 @@ static OSErr FindExtentRecord(
        u_int32_t                       *foundHint)
 {
        FCB *                           fcb;
-       BTreeIterator           btIterator;
+       struct BTreeIterator *btIterator = NULL;
        FSBufferDescriptor      btRecord;
        OSErr                           err;
        u_int16_t                       btRecordSize;
@@ -234,14 +234,18 @@ static OSErr FindExtentRecord(
        if (foundHint)
                *foundHint = 0;
        fcb = GetFileControlBlock(vcb->extentsRefNum);
-       
-       bzero(&btIterator, sizeof(btIterator));
+
+       MALLOC (btIterator, struct BTreeIterator*, sizeof(struct BTreeIterator), M_TEMP, M_WAITOK);
+       if (btIterator == NULL) {
+               return memFullErr;  // translates to ENOMEM
+       }
+       bzero(btIterator, sizeof(*btIterator));
 
        if (vcb->vcbSigWord == kHFSSigWord) {
                HFSExtentKey *          extentKeyPtr;
                HFSExtentRecord         extentData;
 
-               extentKeyPtr = (HFSExtentKey*) &btIterator.key;
+               extentKeyPtr = (HFSExtentKey*) &btIterator->key;
                extentKeyPtr->keyLength = kHFSExtentKeyMaximumLength;
                extentKeyPtr->forkType = forkType;
                extentKeyPtr->fileID = fileID;
@@ -251,10 +255,10 @@ static OSErr FindExtentRecord(
                btRecord.itemSize = sizeof(HFSExtentRecord);
                btRecord.itemCount = 1;
 
-               err = BTSearchRecord(fcb, &btIterator, &btRecord, &btRecordSize, &btIterator);
+               err = BTSearchRecord(fcb, btIterator, &btRecord, &btRecordSize, btIterator);
 
                if (err == btNotFound && allowPrevious) {
-                       err = BTIterateRecord(fcb, kBTreePrevRecord, &btIterator, &btRecord, &btRecordSize);
+                       err = BTIterateRecord(fcb, kBTreePrevRecord, btIterator, &btRecord, &btRecordSize);
 
                        //      A previous record may not exist, so just return btNotFound (like we would if
                        //      it was for the wrong file/fork).
@@ -298,7 +302,7 @@ static OSErr FindExtentRecord(
                HFSPlusExtentKey *      extentKeyPtr;
                HFSPlusExtentRecord     extentData;
 
-               extentKeyPtr = (HFSPlusExtentKey*) &btIterator.key;
+               extentKeyPtr = (HFSPlusExtentKey*) &btIterator->key;
                extentKeyPtr->keyLength  = kHFSPlusExtentKeyMaximumLength;
                extentKeyPtr->forkType   = forkType;
                extentKeyPtr->pad                = 0;
@@ -309,10 +313,10 @@ static OSErr FindExtentRecord(
                btRecord.itemSize = sizeof(HFSPlusExtentRecord);
                btRecord.itemCount = 1;
 
-               err = BTSearchRecord(fcb, &btIterator, &btRecord, &btRecordSize, &btIterator);
+               err = BTSearchRecord(fcb, btIterator, &btRecord, &btRecordSize, btIterator);
 
                if (err == btNotFound && allowPrevious) {
-                       err = BTIterateRecord(fcb, kBTreePrevRecord, &btIterator, &btRecord, &btRecordSize);
+                       err = BTIterateRecord(fcb, kBTreePrevRecord, btIterator, &btRecord, &btRecordSize);
 
                        //      A previous record may not exist, so just return btNotFound (like we would if
                        //      it was for the wrong file/fork).
@@ -336,7 +340,9 @@ static OSErr FindExtentRecord(
        }
 
        if (foundHint)
-               *foundHint = btIterator.hint.nodeNum;
+               *foundHint = btIterator->hint.nodeNum;
+
+       FREE(btIterator, M_TEMP);
        return err;
 }
 
@@ -348,7 +354,7 @@ static OSErr CreateExtentRecord(
        HFSPlusExtentRecord     extents,
        u_int32_t                       *hint)
 {
-       BTreeIterator btIterator;
+       struct BTreeIterator *btIterator = NULL;
        FSBufferDescriptor      btRecord;
        u_int16_t  btRecordSize;
        int  lockflags;
@@ -357,7 +363,11 @@ static OSErr CreateExtentRecord(
        err = noErr;
        *hint = 0;
 
-       bzero(&btIterator, sizeof(btIterator));
+       MALLOC (btIterator, struct BTreeIterator*, sizeof(struct BTreeIterator), M_TEMP, M_WAITOK);
+       if (btIterator == NULL) {
+               return memFullErr;  // translates to ENOMEM
+       }
+       bzero(btIterator, sizeof(*btIterator));
 
        /*
         * The lock taken by callers of ExtendFileC is speculative and
@@ -377,7 +387,7 @@ static OSErr CreateExtentRecord(
                btRecord.itemSize = btRecordSize;
                btRecord.itemCount = 1;
 
-               keyPtr = (HFSExtentKey*) &btIterator.key;
+               keyPtr = (HFSExtentKey*) &btIterator->key;
                keyPtr->keyLength       = kHFSExtentKeyMaximumLength;
                keyPtr->forkType        = key->forkType;
                keyPtr->fileID          = key->fileID;
@@ -391,19 +401,20 @@ static OSErr CreateExtentRecord(
                btRecord.itemSize = btRecordSize;
                btRecord.itemCount = 1;
 
-               BlockMoveData(key, &btIterator.key, sizeof(HFSPlusExtentKey));
+               BlockMoveData(key, &btIterator->key, sizeof(HFSPlusExtentKey));
        }
 
        if (err == noErr)
-               err = BTInsertRecord(GetFileControlBlock(vcb->extentsRefNum), &btIterator, &btRecord, btRecordSize);
+               err = BTInsertRecord(GetFileControlBlock(vcb->extentsRefNum), btIterator, &btRecord, btRecordSize);
 
        if (err == noErr)
-               *hint = btIterator.hint.nodeNum;
+               *hint = btIterator->hint.nodeNum;
 
        (void) BTFlushPath(GetFileControlBlock(vcb->extentsRefNum));
        
        hfs_systemfile_unlock(vcb, lockflags);
-       
+
+       FREE (btIterator, M_TEMP);      
        return err;
 }
 
@@ -414,17 +425,21 @@ static OSErr DeleteExtentRecord(
        u_int32_t                       fileID,
        u_int32_t                       startBlock)
 {
-       BTreeIterator btIterator;
+       struct BTreeIterator *btIterator = NULL;
        OSErr                           err;
        
        err = noErr;
 
-       bzero(&btIterator, sizeof(btIterator));
+       MALLOC (btIterator, struct BTreeIterator*, sizeof(struct BTreeIterator), M_TEMP, M_WAITOK);
+       if (btIterator == NULL) {
+               return memFullErr;  // translates to ENOMEM
+       }
+       bzero(btIterator, sizeof(*btIterator));
        
        if (vcb->vcbSigWord == kHFSSigWord) {
                HFSExtentKey *  keyPtr;
 
-               keyPtr = (HFSExtentKey*) &btIterator.key;
+               keyPtr = (HFSExtentKey*) &btIterator->key;
                keyPtr->keyLength       = kHFSExtentKeyMaximumLength;
                keyPtr->forkType        = forkType;
                keyPtr->fileID          = fileID;
@@ -433,7 +448,7 @@ static OSErr DeleteExtentRecord(
        else {          //      HFS Plus volume
                HFSPlusExtentKey *      keyPtr;
 
-               keyPtr = (HFSPlusExtentKey*) &btIterator.key;
+               keyPtr = (HFSPlusExtentKey*) &btIterator->key;
                keyPtr->keyLength       = kHFSPlusExtentKeyMaximumLength;
                keyPtr->forkType        = forkType;
                keyPtr->pad                     = 0;
@@ -441,9 +456,11 @@ static OSErr DeleteExtentRecord(
                keyPtr->startBlock      = startBlock;
        }
 
-       err = BTDeleteRecord(GetFileControlBlock(vcb->extentsRefNum), &btIterator);
+       err = BTDeleteRecord(GetFileControlBlock(vcb->extentsRefNum), btIterator);
        (void) BTFlushPath(GetFileControlBlock(vcb->extentsRefNum));
        
+
+       FREE(btIterator, M_TEMP);
        return err;
 }
 
@@ -497,7 +514,6 @@ OSErr MapFileBlockC (
        //
        //      Determine the end of the available space.  It will either be the end of the extent,
        //      or the file's PEOF, whichever is smaller.
-       
        //
        dataEnd = (off_t)((off_t)(nextFABN) * (off_t)(allocBlockSize));   // Assume valid data through end of this extent
        if (((off_t)fcb->ff_blocks * (off_t)allocBlockSize) < dataEnd)    // Is PEOF shorter?
@@ -536,10 +552,13 @@ OSErr MapFileBlockC (
                if (tmpOff <= 0) {
                        return EINVAL;
                }
-               if (tmpOff > (off_t)(numberOfBytes))
+
+               if (tmpOff > (off_t)(numberOfBytes)) {
                        *availableBytes = numberOfBytes;  // more there than they asked for, so pin the output
-               else
+               }
+               else {
                        *availableBytes = tmpOff;
+               }
        }
 
        return noErr;
@@ -1890,7 +1909,7 @@ static OSErr UpdateExtentRecord (ExtendedVCB *vcb, FCB  *fcb, int deleted,
                }
        }
        else {
-               BTreeIterator btIterator;
+               struct BTreeIterator *btIterator = NULL;
                FSBufferDescriptor btRecord;
                u_int16_t btRecordSize;
                FCB * btFCB;
@@ -1900,8 +1919,12 @@ static OSErr UpdateExtentRecord (ExtendedVCB *vcb, FCB  *fcb, int deleted,
                //      Need to find and change a record in Extents BTree
                //
                btFCB = GetFileControlBlock(vcb->extentsRefNum);
-
-               bzero(&btIterator, sizeof(btIterator));
+               
+               MALLOC (btIterator, struct BTreeIterator*, sizeof(struct BTreeIterator), M_TEMP, M_WAITOK);
+               if (btIterator == NULL) {
+                       return memFullErr;  // translates to ENOMEM
+               }
+               bzero(btIterator, sizeof(*btIterator));
 
                /*
                 * The lock taken by callers of ExtendFileC/TruncateFileC is
@@ -1916,49 +1939,51 @@ static OSErr UpdateExtentRecord (ExtendedVCB *vcb, FCB  *fcb, int deleted,
                        HFSExtentKey *  key;                            // Actual extent key used on disk in HFS
                        HFSExtentRecord foundData;                      // The extent data actually found
 
-                       key = (HFSExtentKey*) &btIterator.key;
+                       key = (HFSExtentKey*) &btIterator->key;
                        key->keyLength  = kHFSExtentKeyMaximumLength;
                        key->forkType   = extentFileKey->forkType;
                        key->fileID             = extentFileKey->fileID;
                        key->startBlock = extentFileKey->startBlock;
 
-                       btIterator.hint.index = 0;
-                       btIterator.hint.nodeNum = extentBTreeHint;
+                       btIterator->hint.index = 0;
+                       btIterator->hint.nodeNum = extentBTreeHint;
 
                        btRecord.bufferAddress = &foundData;
                        btRecord.itemSize = sizeof(HFSExtentRecord);
                        btRecord.itemCount = 1;
 
-                       err = BTSearchRecord(btFCB, &btIterator, &btRecord, &btRecordSize, &btIterator);
+                       err = BTSearchRecord(btFCB, btIterator, &btRecord, &btRecordSize, btIterator);
                        
                        if (err == noErr)
                                err = HFSPlusToHFSExtents(extentData, (HFSExtentDescriptor *)&foundData);
 
                        if (err == noErr)
-                               err = BTReplaceRecord(btFCB, &btIterator, &btRecord, btRecordSize);
+                               err = BTReplaceRecord(btFCB, btIterator, &btRecord, btRecordSize);
                        (void) BTFlushPath(btFCB);
                }
                else {          //      HFS Plus volume
                        HFSPlusExtentRecord     foundData;              // The extent data actually found
 
-                       BlockMoveData(extentFileKey, &btIterator.key, sizeof(HFSPlusExtentKey));
+                       BlockMoveData(extentFileKey, &btIterator->key, sizeof(HFSPlusExtentKey));
 
-                       btIterator.hint.index = 0;
-                       btIterator.hint.nodeNum = extentBTreeHint;
+                       btIterator->hint.index = 0;
+                       btIterator->hint.nodeNum = extentBTreeHint;
 
                        btRecord.bufferAddress = &foundData;
                        btRecord.itemSize = sizeof(HFSPlusExtentRecord);
                        btRecord.itemCount = 1;
 
-                       err = BTSearchRecord(btFCB, &btIterator, &btRecord, &btRecordSize, &btIterator);
+                       err = BTSearchRecord(btFCB, btIterator, &btRecord, &btRecordSize, btIterator);
        
                        if (err == noErr) {
                                BlockMoveData(extentData, &foundData, sizeof(HFSPlusExtentRecord));
-                               err = BTReplaceRecord(btFCB, &btIterator, &btRecord, btRecordSize);
+                               err = BTReplaceRecord(btFCB, btIterator, &btRecord, btRecordSize);
                        }
                        (void) BTFlushPath(btFCB);
                }
                hfs_systemfile_unlock(vcb, lockflags);
+
+               FREE(btIterator, M_TEMP);
        }
        
        return err;