diff options
Diffstat (limited to 'win/tclWinChan.c')
| -rw-r--r-- | win/tclWinChan.c | 88 |
1 files changed, 84 insertions, 4 deletions
diff --git a/win/tclWinChan.c b/win/tclWinChan.c index ad10251..530492d 100644 --- a/win/tclWinChan.c +++ b/win/tclWinChan.c @@ -9,7 +9,7 @@ * See the file "license.terms" for information on usage and redistribution * of this file, and for a DISCLAIMER OF ALL WARRANTIES. * - * RCS: @(#) $Id: tclWinChan.c,v 1.22 2002/05/13 13:20:00 vincentdarley Exp $ + * RCS: @(#) $Id: tclWinChan.c,v 1.23 2002/05/24 21:19:09 dkf Exp $ */ #include "tclWinInt.h" @@ -89,7 +89,9 @@ static int FileInputProc _ANSI_ARGS_((ClientData instanceData, char *buf, int toRead, int *errorCode)); static int FileOutputProc _ANSI_ARGS_((ClientData instanceData, CONST char *buf, int toWrite, int *errorCode)); -static Tcl_WideInt FileSeekProc _ANSI_ARGS_((ClientData instanceData, +static int FileSeekProc _ANSI_ARGS_((ClientData instanceData, + long offset, int mode, int *errorCode)); +static Tcl_WideInt FileWideSeekProc _ANSI_ARGS_((ClientData instanceData, Tcl_WideInt offset, int mode, int *errorCode)); static void FileSetupProc _ANSI_ARGS_((ClientData clientData, int flags)); @@ -103,7 +105,7 @@ static void FileWatchProc _ANSI_ARGS_((ClientData instanceData, static Tcl_ChannelType fileChannelType = { "file", /* Type name. */ - TCL_CHANNEL_VERSION_2, /* v2 channel */ + TCL_CHANNEL_VERSION_3, /* v3 channel */ FileCloseProc, /* Close proc. */ FileInputProc, /* Input proc. */ FileOutputProc, /* Output proc. */ @@ -116,6 +118,7 @@ static Tcl_ChannelType fileChannelType = { FileBlockProc, /* Set blocking or non-blocking mode.*/ NULL, /* flush proc. */ NULL, /* handler proc. */ + FileWideSeekProc, /* Wide seek proc. */ }; #ifdef HAVE_NO_SEH @@ -436,9 +439,86 @@ FileCloseProc(instanceData, interp) *---------------------------------------------------------------------- */ -static Tcl_WideInt +static int FileSeekProc(instanceData, offset, mode, errorCodePtr) ClientData instanceData; /* File state. */ + long offset; /* Offset to seek to. */ + int mode; /* Relative to where should we seek? */ + int *errorCodePtr; /* To store error code. */ +{ + FileInfo *infoPtr = (FileInfo *) instanceData; + DWORD moveMethod; + DWORD newPos, newPosHigh; + DWORD oldPos, oldPosHigh; + + *errorCodePtr = 0; + if (mode == SEEK_SET) { + moveMethod = FILE_BEGIN; + } else if (mode == SEEK_CUR) { + moveMethod = FILE_CURRENT; + } else { + moveMethod = FILE_END; + } + + /* + * Save our current place in case we need to roll-back the seek. + */ + oldPosHigh = (DWORD)0; + oldPos = SetFilePointer(infoPtr->handle, (LONG)0, &oldPosHigh, + FILE_CURRENT); + if (oldPos == INVALID_SET_FILE_POINTER) { + int winError = GetLastError(); + if (winError != NO_ERROR) { + TclWinConvertError(winError); + *errorCodePtr = errno; + return -1; + } + } + + newPosHigh = (DWORD)(offset < 0 ? -1 : 0); + newPos = SetFilePointer(infoPtr->handle, (LONG) offset, &newPosHigh, + moveMethod); + if (newPos == INVALID_SET_FILE_POINTER) { + int winError = GetLastError(); + if (winError != NO_ERROR) { + TclWinConvertError(winError); + *errorCodePtr = errno; + return -1; + } + } + + /* + * Check for expressability in our return type, and roll-back otherwise. + */ + if (newPosHigh != 0) { + *errorCodePtr = EOVERFLOW; + SetFilePointer(infoPtr->handle, (LONG)oldPos, &oldPosHigh, FILE_BEGIN); + return -1; + } + return (int) newPos; +} + +/* + *---------------------------------------------------------------------- + * + * FileWideSeekProc -- + * + * Seeks on a file-based channel. Returns the new position. + * + * Results: + * -1 if failed, the new position if successful. If failed, it + * also sets *errorCodePtr to the error code. + * + * Side effects: + * Moves the location at which the channel will be accessed in + * future operations. + * + *---------------------------------------------------------------------- + */ + +static Tcl_WideInt +FileWideSeekProc(instanceData, offset, mode, errorCodePtr) + ClientData instanceData; /* File state. */ Tcl_WideInt offset; /* Offset to seek to. */ int mode; /* Relative to where should we seek? */ int *errorCodePtr; /* To store error code. */ |