file.c

nedit 是一款linux下的开发源码的功能强大的编辑器

	wrapToggle = XtVaCreateManagedWidget("addWrap",
	    	xmToggleButtonWidgetClass, formatForm, XmNlabelString,
	    	s1=XmStringCreateSimple("Add line breaks where wrapped"),
    		XmNalignment, XmALIGNMENT_BEGINNING,
		XmNmnemonic, 'A',
		XmNtopAttachment, XmATTACH_WIDGET,
		XmNtopWidget, formatBtns,
		XmNleftAttachment, XmATTACH_FORM, NULL);
	XtAddCallback(wrapToggle, XmNvalueChangedCallback, addWrapCB,
    	    	addWrap);
	XmStringFree(s1);
    }
    *addWrap = False;
    XtVaSetValues(XmFileSelectionBoxGetChild(fileSB,
    	    XmDIALOG_FILTER_LABEL), XmNmnemonic, 'l', XmNuserData,
    	    XmFileSelectionBoxGetChild(fileSB, XmDIALOG_FILTER_TEXT), NULL);
    XtVaSetValues(XmFileSelectionBoxGetChild(fileSB,
    	    XmDIALOG_DIR_LIST_LABEL), XmNmnemonic, 'D', XmNuserData,
    	    XmFileSelectionBoxGetChild(fileSB, XmDIALOG_DIR_LIST), NULL);
    XtVaSetValues(XmFileSelectionBoxGetChild(fileSB,
    	    XmDIALOG_LIST_LABEL), XmNmnemonic, 'F', XmNuserData,
    	    XmFileSelectionBoxGetChild(fileSB, XmDIALOG_LIST), NULL);
    XtVaSetValues(XmFileSelectionBoxGetChild(fileSB,
    	    XmDIALOG_SELECTION_LABEL), XmNmnemonic,
    	    prompt[strspn(prompt, "lFD")], XmNuserData,
    	    XmFileSelectionBoxGetChild(fileSB, XmDIALOG_TEXT), NULL);
    AddDialogMnemonicHandler(fileSB, FALSE);
    RemapDeleteKey(XmFileSelectionBoxGetChild(fileSB, XmDIALOG_FILTER_TEXT));
    RemapDeleteKey(XmFileSelectionBoxGetChild(fileSB, XmDIALOG_TEXT));
    retVal = HandleCustomNewFileSB(fileSB, fullname,
    	    window->filenameSet ? window->filename : NULL);

    if (retVal != GFN_OK)
    	SetFileDialogDefaultDirectory(savedDefaultDir);
    if (savedDefaultDir != NULL)
    	XtFree(savedDefaultDir);
    return retVal;
}

/*
** Find a name for an untitled file, unique in the name space of in the opened
** files in this session, i.e. Untitled or Untitled_nn, and write it into
** the string "name".
*/
void UniqueUntitledName(char *name)
{
    WindowInfo *w;
    int i;

   for (i=0; i<INT_MAX; i++) {
    	if (i == 0)
    	    sprintf(name, "Untitled");
    	else
    	    sprintf(name, "Untitled_%d", i);
	for (w=WindowList; w!=NULL; w=w->next)
     	    if (!strcmp(w->filename, name))
    	    	break;
    	if (w == NULL)
    	    break;
    }
}

/*
** Check if the file in the window was changed by an external source.
** and put up a warning dialog if it has.
*/
void CheckForChangesToFile(WindowInfo *window)
{
    static WindowInfo *lastCheckWindow;
    static Time lastCheckTime = 0;
    char fullname[MAXPATHLEN];
    struct stat statbuf;
    Time timestamp;
    FILE *fp;
    int resp, silent = 0;
    XWindowAttributes winAttr;
    
    if(!window->filenameSet)
        return;

    /* If last check was very recent, don't impact performance */
    timestamp = XtLastTimestampProcessed(XtDisplay(window->shell));
    if (window == lastCheckWindow &&
            timestamp - lastCheckTime < MOD_CHECK_INTERVAL)
        return;
    lastCheckWindow = window;
    lastCheckTime = timestamp;

    /* Update the status, but don't pop up a dialog if we're called
       from a place where the window might be iconic (e.g., from the
       replace dialog) or on another desktop.
       
       This works, but I bet it costs a round-trip to the server.
       Might be better to capture MapNotify/Unmap events instead. */

    XGetWindowAttributes(XtDisplay(window->shell),
                         XtWindow(window->shell),
                         &winAttr);

    if (winAttr.map_state != IsViewable)
        silent = 1;

    /* Get the file mode and modification time */
    strcpy(fullname, window->path);
    strcat(fullname, window->filename);
    if (stat(fullname, &statbuf) != 0) {
        /* Return if we've already warned the user or we can't warn him now */
        if (window->fileMissing || silent)
            return;
        /* Can't stat the file -- maybe it's been deleted.
           The filename is now invalid */
        window->fileMissing = TRUE;
        window->lastModTime = 1;
        /* Warn the user, if they like to be warned (Maybe this should be its
            own preference setting: GetPrefWarnFileDeleted() ) */
        if (GetPrefWarnFileMods()) {
            /* See note below about pop-up timing and XUngrabPointer */
            XUngrabPointer(XtDisplay(window->shell), timestamp);
            if( errno == EACCES ) 
                resp = 1 + DialogF(DF_ERR, window->shell, 2,
                        "File not Accessible",
                        "You no longer have access to file \"%s\".\n"
                        "Another program may have changed the permissions one of\n"
                        "its parent directories.\nSave as a new file?",
                        "Save As...", "Dismiss", window->filename);
            else
                resp = DialogF(DF_ERR, window->shell, 3, "File not found",
                        "Error while checking the status of file \"%s\":\n"
                        "    \"%s\"\n"
                        "Another program may have deleted or moved it.\n"
                        "Re-Save file or Save as a new file?", "Re-Save",
                        "Save As...", "Dismiss", window->filename,
                        errorString());
            if (resp == 1)
                SaveWindow(window);
            else if (resp == 2)
                SaveWindowAs(window, NULL, 0);
        }
        /* A missing or (re-)saved file can't be read-only. */
        SET_PERM_LOCKED(window->lockReasons, False);
        UpdateWindowTitle(window);
        UpdateWindowReadOnly(window);
        return;
    }
    
    /* Check that the file's read-only status is still correct (but
       only if the file can still be opened successfully in read mode) */
    if (window->fileMode != statbuf.st_mode) {
        window->fileMode = statbuf.st_mode;
        if ((fp = fopen(fullname, "r")) != NULL) {
            int readOnly;
            fclose(fp);
#ifndef DONT_USE_ACCESS 
            readOnly = access(fullname, W_OK) != 0;
#else
            if (((fp = fopen(fullname, "r+")) != NULL)) {
                readOnly = FALSE;
                fclose(fp);
            } else
                readOnly = TRUE;
#endif
            if (IS_PERM_LOCKED(window->lockReasons) != readOnly) {
                SET_PERM_LOCKED(window->lockReasons, readOnly);
                UpdateWindowTitle(window);
                UpdateWindowReadOnly(window);
            }
        }
    }

    /* Warn the user if the file has been modified, unless checking is
       turned off or the user has already been warned.  Popping up a dialog
       from a focus callback (which is how this routine is usually called)
       seems to catch Motif off guard, and if the timing is just right, the
       dialog can be left with a still active pointer grab from a Motif menu
       which is still in the process of popping down.  The workaround, below,
       of calling XUngrabPointer is inelegant but seems to fix the problem. */
    if (!silent && 
            ((window->lastModTime != 0 && 
              window->lastModTime != statbuf.st_mtime) ||
             window->fileMissing)  ){
        window->lastModTime = 0;        /* Inhibit further warnings */
        window->fileMissing = FALSE;
        if (!GetPrefWarnFileMods())
            return;
        if (GetPrefWarnRealFileMods() &&
	    !cmpWinAgainstFile(window, fullname)) {
	    /* Contents hasn't changed. Update the modification time. */
	    window->lastModTime = statbuf.st_mtime;
	    return;
	}
        XUngrabPointer(XtDisplay(window->shell), timestamp);
        if (window->fileChanged)
            resp = DialogF(DF_WARN, window->shell, 2,
                    "File modified externally",
                    "%s has been modified by another program.  Reload?\n\n"
                    "WARNING: Reloading will discard changes made in this\n"
                    "editing session!", "Reload", "Dismiss", window->filename);
        else
            resp = DialogF(DF_WARN, window->shell, 2,
                    "File modified externally",
                    "%s has been modified by another\nprogram.  Reload?",
                    "Reload", "Dismiss", window->filename);
        if (resp == 1)
            RevertToSaved(window);
    }
}

/*
** Return true if the file displayed in window has been modified externally
** to nedit.  This should return FALSE if the file has been deleted or is
** unavailable.
*/
static int fileWasModifiedExternally(WindowInfo *window)
{    
    char fullname[MAXPATHLEN];
    struct stat statbuf;
    
    if(!window->filenameSet)
        return FALSE;
    /* if (window->lastModTime == 0)
	return FALSE; */
    strcpy(fullname, window->path);
    strcat(fullname, window->filename);
    if (stat(fullname, &statbuf) != 0)
        return FALSE;
    if (window->lastModTime == statbuf.st_mtime)
	return FALSE;
    if (GetPrefWarnRealFileMods() &&
	!cmpWinAgainstFile(window, fullname)) {
	return FALSE;
    }
    return TRUE;
}

/*
** Check the read-only or locked status of the window and beep and return
** false if the window should not be written in.
*/
int CheckReadOnly(WindowInfo *window)
{
    if (IS_ANY_LOCKED(window->lockReasons)) {
    	XBell(TheDisplay, 0);
	return True;
    }
    return False;
}

/*
** Wrapper for strerror so all the calls don't have to be ifdef'd for VMS.
*/
static const char *errorString(void)
{
#ifdef VMS
    return strerror(errno, vaxc$errno);
#else
    return strerror(errno);
#endif
}

#ifdef VMS
/*
** Removing the VMS version number from a file name (if has one).
*/
void removeVersionNumber(char *fileName)
{
    char *versionStart;
    
    versionStart = strrchr(fileName, ';');
    if (versionStart != NULL)
    	*versionStart = '\0';
}
#endif /*VMS*/

/*
** Callback procedure for File Format toggle buttons.  Format is stored
** in userData field of widget button
*/
static void setFormatCB(Widget w, XtPointer clientData, XtPointer callData)
{
    if (XmToggleButtonGetState(w))
	XtVaGetValues(w, XmNuserData, clientData, NULL);
}

/*
** Callback procedure for toggle button requesting newlines to be inserted
** to emulate continuous wrapping.
*/
static void addWrapCB(Widget w, XtPointer clientData, XtPointer callData)
{
    int resp;
    int *addWrap = (int *)clientData;
    
    if (XmToggleButtonGetState(w))
    {
        resp = DialogF(DF_WARN, w, 2, "Add Wrap",
                "This operation adds permanent line breaks to\n"
                "match the automatic wrapping done by the\n"
                "Continuous Wrap mode Preferences Option.\n\n"
                "*** This Option is Irreversable ***\n\n"
                "Once newlines are inserted, continuous wrapping\n"
                "will no longer work automatically on these lines", "OK",
                "Cancel");
        if (resp == 2)
        {
            XmToggleButtonSetState(w, False, False);
            *addWrap = False;
        } else
        {
            *addWrap = True;
        }
    } else
    {
        *addWrap = False;
    }
}

/*
** Change a window created in NEdit's continuous wrap mode to the more
** conventional Unix format of embedded newlines.  Indicate to the user
** by turning off Continuous Wrap mode.
*/
static void addWrapNewlines(WindowInfo *window)
{
    int fileLen, i, insertPositions[MAX_PANES], topLines[MAX_PANES];
    int horizOffset;
    Widget text;
    char *fileString;
	
    /* save the insert and scroll positions of each pane */
    for (i=0; i<=window->nPanes; i++) {
    	text = i==0 ? window->textArea : window->textPanes[i-1];
    	insertPositions[i] = TextGetCursorPos(text);
    	TextGetScroll(text, &topLines[i], &horizOffset);
    }

    /* Modify the buffer to add wrapping */
    fileString = TextGetWrapped(window->textArea, 0,
    	    window->buffer->length, &fileLen);
    BufSetAll(window->buffer, fileString);
    XtFree(fileString);

    /* restore the insert and scroll positions of each pane */
    for (i=0; i<=window->nPanes; i++) {
    	text = i==0 ? window->textArea : window->textPanes[i-1];
	TextSetCursorPos(text, insertPositions[i]);
	TextSetScroll(text, topLines[i], 0);
    }

    /* Show the user that something has happened by turning off
       Continuous Wrap mode */
    XmToggleButtonSetState(window->continuousWrapItem, False, True);
}

/* 
 * Number of bytes read at once by cmpWinAgainstFile
 */
#define PREFERRED_CMPBUF_LEN 32768

/* 
 * Check if the contens of the textBuffer *buf is equal 
 * the contens of the file named fileName. The format of
 * the file (UNIX/DOS/MAC) is handled properly.
 *
 * Return values
 *   0: no difference found
 *  !0: difference found or could not compare contents.
 */
static int cmpWinAgainstFile(WindowInfo *window, const char *fileName)
{
    char    fileString[PREFERRED_CMPBUF_LEN + 2];
    struct  stat statbuf;
    int     fileLen, restLen, nRead, bufPos, rv, offset, filePos;
    char    pendingCR = 0;
    int	    fileFormat = window->fileFormat;
    char    message[MAXPATHLEN+50];
    textBuffer *buf = window->buffer;
    FILE   *fp;

    fp = fopen(fileName, "r");
    if (!fp)
        return (1);
    if (fstat(fileno(fp), &statbuf) != 0) {
        fclose(fp);
        return (1);
    }

    fileLen = statbuf.st_size;
    /* For DOS files, we can't simply check the length */
    if (fileFormat != DOS_FILE_FORMAT) {
	if (fileLen != buf->length) {
	    fclose(fp);
	    return (1);
        }
    } else {
	/* If a DOS file is smaller on disk, it's certainly different */
	if (fileLen < buf->length) {
	    fclose(fp);
	    return (1);
	}
    }
    
    /* For large files, the comparison can take a while. If it takes too long,
       the user should be given a clue about what is happening. */
    sprintf(message, "Comparing externally modified %s ...", window->filename);
    restLen = min(PREFERRED_CMPBUF_LEN, fileLen);
    bufPos = 0;
    filePos = 0;
    while (restLen > 0) {
        AllWindowsBusy(message);
        if (pendingCR) {
           fileString[0] = pendingCR;
           offset = 1;
        } else {
           offset = 0;
        }

        nRead = fread(fileString+offset, sizeof(char), restLen, fp);
        if (nRead != restLen) {
            fclose(fp);
            AllWindowsUnbusy();
            return (1);
        }
        filePos += nRead;
        
        nRead += offset;

        if (fileFormat == MAC_FILE_FORMAT)
            ConvertFromMacFileString(fileString, nRead);
        else if (fileFormat == DOS_FILE_FORMAT)
            ConvertFromDosFileString(fileString, &nRead, &pendingCR);

        /* Beware of 0 chars ! */
        BufSubstituteNullChars(fileString, nRead, buf);
        rv = BufCmp(buf, bufPos, nRead, fileString);
        if (rv) {
            fclose(fp);
            AllWindowsUnbusy();
            return (rv);
        }
        bufPos += nRead;
        restLen = min(fileLen - filePos, PREFERRED_CMPBUF_LEN);
    }
    AllWindowsUnbusy();
    fclose(fp);
    if (pendingCR) {
	rv = BufCmp(buf, bufPos, 1, &pendingCR);
	if (rv) {
	    return (rv);
	}
	bufPos += 1;
    }
    if (bufPos != buf->length) { 
	return (1);
    }
    return (0);
}

static int min(int i1, int i2)
{
    return i1 <= i2 ? i1 : i2;
}