Added thread mutex/release calls around the potentially contested regions of the code:

Mounting a file system
Unmounting a file system
Reading data from an archive file

The mutexes, as implemented, allow only one thread at a time access to the innards of ZipVfs. It does not try to handle the cases where two archives may be open by two different threads. (One will still have to wait until the other has finished.)

Removed all of the compiler warnings under Unix

(Still have to test the code under Windows.)

1 files changed, 39 insertions, 55 deletions

diff --git a/generic/tclZipVfs.c b/generic/tclZipVfs.c
index c9160ba..d4f8f68 100755
--- a/generic/tclZipVfs.c
+++ b/generic/tclZipVfs.c
@@ -57,6 +57,8 @@
 #include <stdlib.h>
 #include "tcl.h"
 
+TCL_DECLARE_MUTEX(ArchiveFileAccess)
+
 #undef ZIPVFSCRYPT
 #ifdef ZIPVFSCRYPT
 /* Some modifications to support encrypted files */
@@ -79,8 +81,9 @@ extern const unsigned long *crc_32_tab;
 */
 #define COMPR_BUF_SIZE   32768
 static int openarch = 0;	/* Set to 1 when opening archive. */
+#ifdef __WIN32__
 static int maptolower=0;
-
+#endif
 /*
 ** All static variables are collected into a structure named "local".
 ** That way, it is clear in the code when we are using a static
@@ -140,19 +143,6 @@ typedef struct ZvfsFile {
 #define INT16(B, N) (B[N] + (B[N+1]<<8))
 #define INT32(B, N) (INT16(B,N) + (B[N+2]<<16) + (B[N+3]<<24))
 
-/*
-** Write a 16- or 32-bit integer as little-endian into the given buffer.
-*/
-static void put16(char *z, int v){
-  z[0] = v & 0xff;
-  z[1] = (v>>8) & 0xff;
-}
-static void put32(char *z, int v){
-  z[0] = v & 0xff;
-  z[1] = (v>>8) & 0xff;
-  z[2] = (v>>16) & 0xff;
-  z[3] = (v>>24) & 0xff;
-}
 
 /* Convert DOS time to unix time. */
 static time_t DosTimeDate(int dosDate, int dosTime){
@@ -169,25 +159,6 @@ static time_t DosTimeDate(int dosDate, int dosTime){
   return mktime(tm);
 }
 
-/*
-** Translate a DOS time and date stamp into a human-readable string.
-*/
-static void translateDosTimeDate(char *zStr, int dosDate, int dosTime){
-  static char *zMonth[] = { "nil",
-    "Jan", "Feb", "Mar", "Apr", "May", "Jun",
-    "Jul", "Aug", "Sep", "Oct", "Nov", "Dec",
-  };
- 
-  sprintf(zStr, "%02d-%s-%d %02d:%02d:%02d", 
-    dosDate & 0x1f,
-    zMonth[ ((dosDate&0x1e0)>>5) ],
-    ((dosDate&0xfe00)>>9) + 1980,
-    (dosTime&0xf800)>>11,
-    (dosTime&0x7e)>>5,
-    dosTime&0x1f
-  );
-}
-
 /* Return count of char ch in str */
 int strchrcnt(char *str, char ch) {
   int cnt=0;
@@ -476,15 +447,17 @@ int Zvfs_Mount(
 	Tcl_Free((char *)zTrueName);
 	return TCL_OK;
     }
+    Tcl_MutexLock(&ArchiveFileAccess);
     chan = Tcl_OpenFileChannel(interp, zArchive, "r", 0);
     if (!chan) {
-	return TCL_ERROR;
+        Tcl_MutexUnlock(&ArchiveFileAccess);
+        return TCL_ERROR;
     }
     if (Tcl_SetChannelOption(interp, chan, "-translation", "binary") != TCL_OK){
-	return TCL_ERROR;
+	goto closeReleaseDie;
     }
     if (Tcl_SetChannelOption(interp, chan, "-encoding", "binary") != TCL_OK) {
-	return TCL_ERROR;
+	goto closeReleaseDie;
     }
 
     /*
@@ -496,7 +469,7 @@ int Zvfs_Mount(
     Tcl_Read(chan, (char *) zBuf, 22);
     if (memcmp(zBuf, "\120\113\05\06", 4)) {
 	if(interp) Tcl_AppendResult(interp, "not a ZIP archive", NULL);
-	return TCL_ERROR;
+        goto closeReleaseDie;
     }
 
     /*
@@ -510,9 +483,7 @@ int Zvfs_Mount(
 	if (interp) {
           Tcl_AppendResult(interp, "already mounted at ", pArchive->zMountPoint,0);
 	}
-	Tcl_Free(zArchiveName);
-	Tcl_Close(interp, chan);
-	return TCL_ERROR;
+        goto closeReleaseDie;
     }
 
     /*
@@ -641,11 +612,16 @@ int Zvfs_Mount(
 	Tcl_Seek(chan, lenExtra, SEEK_CUR);
     }
     Tcl_Close(interp, chan);
-
     if (zTrueName) {
 	Tcl_Free(zTrueName);
     }
+    Tcl_MutexUnlock(&ArchiveFileAccess);
     return TCL_OK;
+
+closeReleaseDie:
+  Tcl_Close(interp, chan);
+  Tcl_MutexUnlock(&ArchiveFileAccess);
+  return TCL_ERROR;
 }
 
 /*
@@ -682,6 +658,7 @@ static int Zvfs_Unmount(
     if (pEntry == 0) {
 	return 0;
     }
+    Tcl_MutexLock(&ArchiveFileAccess);
     pArchive = Tcl_GetHashValue(pEntry);
     Tcl_DeleteHashEntry(pEntry);
     Tcl_Free(pArchive->zName);
@@ -705,6 +682,7 @@ static int Zvfs_Unmount(
 	Tcl_Free(pFile->zName);
 	Tcl_Free((void *) pFile);
     }
+    Tcl_MutexUnlock(&ArchiveFileAccess);
     return 1;
 }
 
@@ -980,6 +958,7 @@ static int vfsClose(
     Tcl_Close(interp, pInfo->chan);
     Tcl_DeleteExitHandler(vfsExit, pInfo);
   }
+  Tcl_MutexUnlock(&ArchiveFileAccess);
   Tcl_Free((char*)pInfo);
   return TCL_OK;
 }
@@ -1019,12 +998,14 @@ static int vfsRead (
   int *pErrorCode          /* Location of error flag */
   ){ /* Read and decompress all data for the associated file into the specified buffer */
   ZvfsChannelInfo* pInfo = (ZvfsChannelInfo*) instanceData;
+  int len;
+#ifdef ZIPVFSCRYPT
   unsigned char encryptHdr[12];
   int C;
   int temp;
   int i;
-  int len;
   char pwdbuf[20];
+#endif
 
   if( (unsigned long)toRead > pInfo->nByte ){
     toRead = pInfo->nByte;
@@ -1054,7 +1035,7 @@ static int vfsRead (
   if( pInfo->isCompressed ){
     int err = Z_OK;
     z_stream *stream = &pInfo->stream;
-    stream->next_out = buf;
+    stream->next_out = (unsigned char *)buf;
     stream->avail_out = toRead;
     while (stream->avail_out) {
       if (!stream->avail_in) {
@@ -1062,7 +1043,7 @@ static int vfsRead (
         if (len > COMPR_BUF_SIZE) {
           len = COMPR_BUF_SIZE;
         }
-        len = Tcl_Read(pInfo->chan, pInfo->zBuf, len);
+        len = Tcl_Read(pInfo->chan, (char *)pInfo->zBuf, len);
 #ifdef ZIPVFSCRYPT
 
 		if (pInfo->isEncrypted) {
@@ -1224,6 +1205,8 @@ static Tcl_Channel ZvfsFileOpen(
     return NULL;
   }
   openarch = 1;
+  
+  Tcl_MutexLock(&ArchiveFileAccess);
   chan = Tcl_OpenFileChannel(interp, pFile->pArchive->zName, "r", 0);
   openarch = 0;
   
@@ -1231,23 +1214,22 @@ static Tcl_Channel ZvfsFileOpen(
 	local.firstMount = pFile->pArchive->zName;
   }
   if( chan==0 ){
+    Tcl_MutexUnlock(&ArchiveFileAccess);
     return 0;
   }
   if(  Tcl_SetChannelOption(interp, chan, "-translation", "binary")
     || Tcl_SetChannelOption(interp, chan, "-encoding", "binary")
   ){
     /* this should never happen */
-    Tcl_Close(0, chan);
-    return 0;
+    goto closeReleaseDie;
   }
   Tcl_Seek(chan, pFile->iOffset, SEEK_SET);
-  Tcl_Read(chan, zBuf, 30);
+  Tcl_Read(chan, (char *)zBuf, 30);
   if( memcmp(zBuf, "\120\113\03\04", 4) ){
     if( interp ){
       Tcl_AppendResult(interp, "local header mismatch: ", NULL);
     }
-    Tcl_Close(interp, chan);
-    return 0;
+    goto closeReleaseDie;
   }
   pInfo = (ZvfsChannelInfo*)Tcl_Alloc( sizeof(*pInfo) );
   pInfo->chan = chan;
@@ -1297,11 +1279,17 @@ static Tcl_Channel ZvfsFileOpen(
   /* Read and decompress the file contents */
   if (pInfo->uBuf) {
     pInfo->uBuf[0] = 0;
-    vfsRead(pInfo, pInfo->uBuf, pInfo->nByte, &errCode);
+    vfsRead(pInfo, (char *)pInfo->uBuf, pInfo->nByte, &errCode);
     pInfo->readSoFar = 0;
   }
 
   return chan;
+
+closeReleaseDie:
+  Tcl_Close(interp, chan);
+  Tcl_MutexUnlock(&ArchiveFileAccess);
+  return NULL;
+
 }
 
 Tcl_Channel Tobe_FSOpenFileChannelProc
@@ -1342,7 +1330,6 @@ int Tobe_FSStatProc _ANSI_ARGS_((Tcl_Obj *pathPtr, Tcl_StatBuf *buf)) {
 ** This routine does an access() system call for a ZVFS file.
 */
 int Tobe_FSAccessProc _ANSI_ARGS_((Tcl_Obj *pathPtr, int mode)) {
-  int len;
     char *path=Tcl_GetString(pathPtr);
     ZvfsFile *pFile;
 
@@ -1401,7 +1388,6 @@ int Tobe_FSMatchInDirectoryProc (
       Tcl_HashEntry *pEntry;     /* Hash table entry */
       Tcl_HashSearch zSearch;   /* Search all mount points */
       ZvfsArchive *pArchive;     /* The ZIP archive being mounted */
-      Tcl_Obj *pVols=0, *pVol;
       char mountpt[200];
       int i=1;
       mountpt[0]='/';
@@ -1474,7 +1460,7 @@ int Tobe_FSMatchInDirectoryProc (
           }
       }
     }
-done:
+
     if (zPattern) {
 	free(zPattern);
     }
@@ -1801,7 +1787,6 @@ int Zvfs_Common_Init(Tcl_Interp *interp) {
 }
 
 int Zvfs_Init(Tcl_Interp *interp){
-  int n;
 #ifdef USE_TCL_STUBS
   if( Tcl_InitStubs(interp,"8.0",0)==0 ){
     return TCL_ERROR;
@@ -1819,7 +1804,6 @@ int Zvfs_Init(Tcl_Interp *interp){
 }
 
 int Zvfs_SafeInit(Tcl_Interp *interp){
-  int n;
 #ifdef USE_TCL_STUBS
   if( Tcl_InitStubs(interp,"8.0",0)==0 ){
     return TCL_ERROR;