Added workaround for malformed HFS option lists.

Added support for skipping junk found at the start of an archive file.

nufxlib-0/Archive.c

@@ -39,6 +39,7 @@ static const uchar kNuSHKSEAID[] =
 #define kNuSEALength1       11946   /* length of archive (4B?) */
 #define kNuSEALength2       12001   /* length of archive (4B?) */
 
+#define kDefaultJunkSkipMax 1024    /* default junk scan size */
 
 static void Nu_CloseAndFree(NuArchive* pArchive);
 
@@ -93,6 +94,8 @@ Nu_NuArchiveNew(NuArchive** ppArchive)
     (*ppArchive)->valMimicSHK = false;
     (*ppArchive)->valMaskDataless = false;
     (*ppArchive)->valStripHighASCII = false;
+    /* bug: this can't be set by application! */
+    (*ppArchive)->valJunkSkipMax = kDefaultJunkSkipMax;
 
     (*ppArchive)->messageHandlerFunc = gNuGlobalErrorMessageHandler;
 
@@ -231,6 +234,7 @@ bail:
  * assumed to start at offset 0.
  *
  * Wrappers must appear in this order:
+ *  Leading junk
  *  Binary II
  *  ShrinkIt SEA (Self-Extracting Archive)
  *
@@ -266,7 +270,9 @@ Nu_UpdateWrapper(NuArchive* pArchive, FILE* fp)
         hasBinary2 = hasSea = true;
         break;
     default:
-        if (pArchive->headerOffset) {
+        if (pArchive->headerOffset != 0 &&
+            pArchive->headerOffset != pArchive->junkOffset)
+        {
             Nu_ReportError(NU_BLOB, kNuErrNone, "Can't fix the wrapper??");
             err = kNuErrInternal;
             goto bail;
@@ -274,7 +280,7 @@ Nu_UpdateWrapper(NuArchive* pArchive, FILE* fp)
             goto bail;
     }
 
-    err = Nu_FSeek(fp, 0, SEEK_SET);
+    err = Nu_FSeek(fp, pArchive->junkOffset, SEEK_SET);
     BailError(err);
 
     if (hasBinary2) {
@@ -290,9 +296,10 @@ Nu_UpdateWrapper(NuArchive* pArchive, FILE* fp)
             goto bail;
         }
 
-        /* archiveLen includes the SEA wrapper, if any */
+        /* archiveLen includes the SEA wrapper, if any, but excludes junk */
         archiveLen = pArchive->newMasterHeader.mhMasterEOF +
-                        (pArchive->headerOffset - kNuBinary2BlockSize);
+                        (pArchive->headerOffset - pArchive->junkOffset) -
+                        kNuBinary2BlockSize;
         archiveLen512 = (archiveLen + 511) / 512;
 
         err = Nu_FSeek(fp, kNuBNYFileSizeLo - kNufileIDLen, SEEK_CUR);
@@ -411,7 +418,9 @@ Nu_AdjustWrapperPadding(NuArchive* pArchive, FILE* fp)
         hasBinary2 = hasSea = true;
         break;
     default:
-        if (pArchive->headerOffset) {
+        if (pArchive->headerOffset != 0 &&
+            pArchive->headerOffset != pArchive->junkOffset)
+        {
             Nu_ReportError(NU_BLOB, kNuErrNone, "Can't check the padding??");
             err = kNuErrInternal;
             goto bail;
@@ -433,7 +442,9 @@ Nu_AdjustWrapperPadding(NuArchive* pArchive, FILE* fp)
 
         err = Nu_FTell(fp, &curOffset);
         BailError(err);
+        curOffset -= pArchive->junkOffset;  /* don't factor junk into account */
 
+        DBUG(("+++ BNY needs %ld bytes of padding\n", curOffset & 0x7f));
         if (curOffset & 0x7f) {
             int i;
 
@@ -473,6 +484,13 @@ bail:
  * also interested in related formats, we try to return a meaningful error
  * code for stuff we recognize (especially Binary II).
  *
+ * If at first we don't succeed, we keep trying further along until we
+ * find something we recognize.  We don't want to just scan for the
+ * NuFile ID, because that might prevent this from working properly with
+ * SEA archives which push the NuFX start out about 12K.  We also wouldn't
+ * be able to update the BNY/SEA wrappers correctly.  So, we inch our way
+ * along until we find something we recognize or get bored.
+ *
  * On exit, the stream will be positioned just past the master header.
  */
 static NuError
@@ -490,7 +508,10 @@ Nu_ReadMasterHeader(NuArchive* pArchive)
     fp = pArchive->archiveFp;       /* saves typing */
     pHeader = &pArchive->masterHeader;
 
-    pArchive->headerOffset = 0;
+    pArchive->junkOffset = 0;
+
+retry:
+    pArchive->headerOffset = pArchive->junkOffset;
     Nu_ReadBytes(pArchive, fp, pHeader->mhNufileID, kNufileIDLen);
     /* may have read fewer than kNufileIDLen; that's okay */
 
@@ -548,6 +569,22 @@ Nu_ReadMasterHeader(NuArchive* pArchive)
     }
 
     if (memcmp(kNuMasterID, pHeader->mhNufileID, kNufileIDLen) != 0) {
+        /*
+         * Doesn't look like a NuFX archive.  Scan forward and see if we
+         * can find the start past some leading junk.  MacBinary headers
+         * and chunks of HTTP seem popular on FTP sites.
+         */
+        if ((pArchive->openMode == kNuOpenRO ||
+             pArchive->openMode == kNuOpenRW) &&
+            pArchive->junkOffset < (long)pArchive->valJunkSkipMax)
+        {
+            pArchive->junkOffset++;
+            DBUG(("+++ scanning from offset %ld\n", pArchive->junkOffset));
+            err = Nu_SeekArchive(pArchive, fp, pArchive->junkOffset, SEEK_SET);
+            BailError(err);
+            goto retry;
+        }
+
         err = kNuErrNotNuFX;
 
         if (isBinary2) {

nufxlib-0/ArchiveIO.c

@@ -24,7 +24,7 @@
  */
 
 /*
- * Read one little-endian bytes, optionally computing a CRC.
+ * Read one byte, optionally computing a CRC.
  */
 uchar
 Nu_ReadOneC(NuArchive* pArchive, FILE* fp, ushort* pCrc)
@@ -38,7 +38,7 @@ Nu_ReadOneC(NuArchive* pArchive, FILE* fp, ushort* pCrc)
     ic = getc(fp);
     *pCrc = Nu_UpdateCRC16((uchar)ic, *pCrc);
 
-    return ic;
+    return (uchar) ic;
 }
 
 uchar

nufxlib-0/ChangeLog.txt

@@ -1,3 +1,11 @@
+2003/10/16  ***** v2.0.1 shipped *****
+
+2003/10/16  fadden
+    - Added workaround for bad HFS option lists created by GSHK.
+    - Added junk-skipping feature.  Up to 1024 bytes of crud (e.g.
+      MacBinary headers or HTTP remnants) will be searched for evidence
+      of an archive.
+
 2003/06/19  sheppy
     - Added support for resource forks and file and aux types when built
       for Mac OS X.

nufxlib-0/Debug.c

@@ -366,7 +366,8 @@ Nu_DebugDumpAll(NuArchive* pArchive)
 
     printf("*Archive pathname: '%s'\n", pArchive->archivePathname);
     printf("*Archive type: %d\n", pArchive->archiveType);
-    printf("*Header offset: %ld\n", pArchive->headerOffset);
+    printf("*Header offset: %ld (junk offset=%ld)\n",
+		pArchive->headerOffset, pArchive->junkOffset);
     printf("*Num records: %ld orig, %ld copy, %ld new\n",
         Nu_RecordSet_GetNumRecords(&pArchive->origRecordSet),
         Nu_RecordSet_GetNumRecords(&pArchive->copyRecordSet),

nufxlib-0/Deferred.c

@@ -2351,6 +2351,8 @@ Nu_Flush(NuArchive* pArchive, long* pStatusFlags)
      * assumption is invalid, we'd need to adjust "headerOffset" earlier,
      * or do lots of data copying.  Looks like Binary II and SEA headers
      * are both fixed size, so we should be okay.
+     *
+     * We also carry forward any unrecognized junk.
      */
     if (pArchive->headerOffset) {
         if (writeToTemp) {

nufxlib-0/NufxLib.h

@@ -33,7 +33,7 @@ extern "C" {
  */
 #define kNuVersionMajor     2
 #define kNuVersionMinor     0
-#define kNuVersionBug       0
+#define kNuVersionBug       1
 
 
 /*
@@ -268,7 +268,8 @@ typedef enum NuValueID {
     kNuValueModifyOrig          = 9,
     kNuValueMimicSHK            = 10,
     kNuValueMaskDataless        = 11,
-    kNuValueStripHighASCII      = 12
+    kNuValueStripHighASCII      = 12,
+    kNuValueJunkSkipMax         = 13
 } NuValueID;
 typedef unsigned long NuValue;
 

nufxlib-0/NufxLibPriv.h

@@ -103,6 +103,9 @@ struct NuArchive {
     char*           archivePathname;        /* pathname or "(stream)" */
     FILE*           archiveFp;
     NuArchiveType   archiveType;
+
+    /* stuff before NuFX; both offsets are from 0, i.e. hdrOff includes junk */
+    long            junkOffset;             /* skip past leading junk */
     long            headerOffset;           /* adjustment for BXY/SEA/BSE */
 
     char*           tmpPathname;            /* temp file, for writes */
@@ -152,6 +155,7 @@ struct NuArchive {
     NuValue         valModifyOrig;          /* modify original arc in place? */
     NuValue         valOnlyUpdateOlder;     /* modify original arc in place? */
     NuValue         valStripHighASCII;      /* during EOL conv, strip hi bit? */
+    NuValue         valJunkSkipMax;         /* scan this far for header */
 
     /* callback functions */
     NuCallback      selectionFilterFunc;

nufxlib-0/Record.c

@@ -953,11 +953,29 @@ Nu_ReadRecordHeader(NuArchive* pArchive, NuRecord* pRecord)
         pRecord->recOptionSize = Nu_ReadTwoC(pArchive, fp, &crc);
         bytesRead += 2;
 
+        /*
+         * It appears GS/ShrinkIt is creating bad option lists, claiming
+         * 36 bytes of data when there's only room for 18.  Since we don't
+         * really pay attention to the option list
+         */
+        if (pRecord->recOptionSize + bytesRead > pRecord->recAttribCount -2) {
+            DBUG(("--- truncating option list from %d to %d\n",
+                pRecord->recOptionSize,
+                pRecord->recAttribCount -2 - bytesRead));
+            if (pRecord->recAttribCount -2 > bytesRead)
+                pRecord->recOptionSize = pRecord->recAttribCount -2 - bytesRead;
+            else
+                pRecord->recOptionSize = 0;
+        }
+
+        /* this is the older test, which rejected funky archives */
         if (pRecord->recOptionSize + bytesRead > pRecord->recAttribCount -2) {
             /* option size exceeds the total attribute area */
             err = kNuErrBadRecord;
             Nu_ReportError(NU_BLOB, kNuErrBadRecord,
-                "Option size exceeds attribs (%u)", pRecord->recOptionSize);
+                "Option size (%u) exceeds attribs (%u,%u-2)",
+                    pRecord->recOptionSize, bytesRead,
+                    pRecord->recAttribCount);
             goto bail;
         }
 

nufxlib-0/Value.c

@@ -8,6 +8,8 @@
  */
 #include "NufxLibPriv.h"
 
+#define kMaxJunkSkipMax 8192
+
 
 /*
  * Get a configurable parameter.
@@ -57,6 +59,9 @@ Nu_GetValue(NuArchive* pArchive, NuValueID ident, NuValue* pValue)
     case kNuValueStripHighASCII:
         *pValue = pArchive->valStripHighASCII;
         break;
+    case kNuValueJunkSkipMax:
+        *pValue = pArchive->valJunkSkipMax;
+        break;
     default:
         err = kNuErrInvalidArg;
         Nu_ReportError(NU_BLOB, err, "Unknown ValueID %d requested", ident);
@@ -168,11 +173,19 @@ Nu_SetValue(NuArchive* pArchive, NuValueID ident, NuValue value)
     case kNuValueStripHighASCII:
         if (value != true && value != false) {
             Nu_ReportError(NU_BLOB, err,
-                "Invalid kNuStripHighASCII value %ld", value);
+                "Invalid kNuValueStripHighASCII value %ld", value);
             goto bail;
         }
         pArchive->valStripHighASCII = value;
         break;
+    case kNuValueJunkSkipMax:
+        if (value > kMaxJunkSkipMax) {
+            Nu_ReportError(NU_BLOB, err,
+                "Invalid kNuValueJunkSkipMax value %ld", value);
+            goto bail;
+        }
+        pArchive->valJunkSkipMax = value;
+        break;
     default:
         Nu_ReportError(NU_BLOB, err, "Unknown ValueID %d requested", ident);
         goto bail;