/* * tkClipboard.c -- * * This file manages the clipboard for the Tk toolkit, * maintaining a collection of data buffers that will be * supplied on demand to requesting applications. * * Copyright (c) 1994 The Regents of the University of California. * Copyright (c) 1994-1997 Sun Microsystems, Inc. * * See the file "license.terms" for information on usage and redistribution * of this file, and for a DISCLAIMER OF ALL WARRANTIES. * * RCS: @(#) $Id: tkClipboard.c,v 1.10 2002/06/19 19:37:54 mdejong Exp $ */ #include "tkInt.h" #include "tkPort.h" #include "tkSelect.h" /* * Prototypes for procedures used only in this file: */ static int ClipboardAppHandler _ANSI_ARGS_((ClientData clientData, int offset, char *buffer, int maxBytes)); static int ClipboardHandler _ANSI_ARGS_((ClientData clientData, int offset, char *buffer, int maxBytes)); static int ClipboardWindowHandler _ANSI_ARGS_(( ClientData clientData, int offset, char *buffer, int maxBytes)); static void ClipboardLostSel _ANSI_ARGS_((ClientData clientData)); static int ClipboardGetProc _ANSI_ARGS_((ClientData clientData, Tcl_Interp *interp, char *portion)); /* *---------------------------------------------------------------------- * * ClipboardHandler -- * * This procedure acts as selection handler for the * clipboard manager. It extracts the required chunk of * data from the buffer chain for a given selection target. * * Results: * The return value is a count of the number of bytes * actually stored at buffer. * * Side effects: * None. * *---------------------------------------------------------------------- */ static int ClipboardHandler(clientData, offset, buffer, maxBytes) ClientData clientData; /* Information about data to fetch. */ int offset; /* Return selection bytes starting at this * offset. */ char *buffer; /* Place to store converted selection. */ int maxBytes; /* Maximum # of bytes to store at buffer. */ { TkClipboardTarget *targetPtr = (TkClipboardTarget*) clientData; TkClipboardBuffer *cbPtr; char *srcPtr, *destPtr; int count = 0; int scanned = 0; size_t length, freeCount; /* * Skip to buffer containing offset byte */ for (cbPtr = targetPtr->firstBufferPtr; ; cbPtr = cbPtr->nextPtr) { if (cbPtr == NULL) { return 0; } if (scanned + cbPtr->length > offset) { break; } scanned += cbPtr->length; } /* * Copy up to maxBytes or end of list, switching buffers as needed. */ freeCount = maxBytes; srcPtr = cbPtr->buffer + (offset - scanned); destPtr = buffer; length = cbPtr->length - (offset - scanned); while (1) { if (length > freeCount) { strncpy(destPtr, srcPtr, freeCount); return maxBytes; } else { strncpy(destPtr, srcPtr, length); destPtr += length; count += length; freeCount -= length; } cbPtr = cbPtr->nextPtr; if (cbPtr == NULL) { break; } srcPtr = cbPtr->buffer; length = cbPtr->length; } return count; } /* *---------------------------------------------------------------------- * * ClipboardAppHandler -- * * This procedure acts as selection handler for retrievals of type * TK_APPLICATION. It returns the name of the application that * owns the clipboard. Note: we can't use the default Tk * selection handler for this selection type, because the clipboard * window isn't a "real" window and doesn't have the necessary * information. * * Results: * The return value is a count of the number of bytes * actually stored at buffer. * * Side effects: * None. * *---------------------------------------------------------------------- */ static int ClipboardAppHandler(clientData, offset, buffer, maxBytes) ClientData clientData; /* Pointer to TkDisplay structure. */ int offset; /* Return selection bytes starting at this * offset. */ char *buffer; /* Place to store converted selection. */ int maxBytes; /* Maximum # of bytes to store at buffer. */ { TkDisplay *dispPtr = (TkDisplay *) clientData; size_t length; char *p; p = dispPtr->clipboardAppPtr->winPtr->nameUid; length = strlen(p); length -= offset; if (length <= 0) { return 0; } if (length > (size_t) maxBytes) { length = maxBytes; } strncpy(buffer, p, length); return length; } /* *---------------------------------------------------------------------- * * ClipboardWindowHandler -- * * This procedure acts as selection handler for retrievals of * type TK_WINDOW. Since the clipboard doesn't correspond to * any particular window, we just return ".". We can't use Tk's * default handler for this selection type, because the clipboard * window isn't a valid window. * * Results: * The return value is 1, the number of non-null bytes stored * at buffer. * * Side effects: * None. * *---------------------------------------------------------------------- */ static int ClipboardWindowHandler(clientData, offset, buffer, maxBytes) ClientData clientData; /* Not used. */ int offset; /* Return selection bytes starting at this * offset. */ char *buffer; /* Place to store converted selection. */ int maxBytes; /* Maximum # of bytes to store at buffer. */ { buffer[0] = '.'; buffer[1] = 0; return 1; } /* *---------------------------------------------------------------------- * * ClipboardLostSel -- * * This procedure is invoked whenever clipboard ownership is * claimed by another window. It just sets a flag so that we * know the clipboard was taken away. * * Results: * None. * * Side effects: * The clipboard is marked as inactive. * *---------------------------------------------------------------------- */ static void ClipboardLostSel(clientData) ClientData clientData; /* Pointer to TkDisplay structure. */ { TkDisplay *dispPtr = (TkDisplay*) clientData; dispPtr->clipboardActive = 0; } /* *---------------------------------------------------------------------- * * Tk_ClipboardClear -- * * Take control of the clipboard and clear out the previous * contents. This procedure must be invoked before any * calls to Tk_ClipboardAppend. * * Results: * A standard Tcl result. If an error occurs, an error message is * left in the interp's result. * * Side effects: * From now on, requests for the CLIPBOARD selection will be * directed to the clipboard manager routines associated with * clipWindow for the display of tkwin. In order to guarantee * atomicity, no event handling should occur between * Tk_ClipboardClear and the following Tk_ClipboardAppend * calls. This procedure may cause a user-defined LostSel command * to be invoked when the CLIPBOARD is claimed, so any calling * function should be reentrant at the point Tk_ClipboardClear is * invoked. * *---------------------------------------------------------------------- */ int Tk_ClipboardClear(interp, tkwin) Tcl_Interp *interp; /* Interpreter to use for error reporting. */ Tk_Window tkwin; /* Window in application that is clearing * clipboard; identifies application and * display. */ { TkWindow *winPtr = (TkWindow *) tkwin; TkDisplay *dispPtr = winPtr->dispPtr; TkClipboardTarget *targetPtr, *nextTargetPtr; TkClipboardBuffer *cbPtr, *nextCbPtr; if (dispPtr->clipWindow == NULL) { int result; result = TkClipInit(interp, dispPtr); if (result != TCL_OK) { return result; } } /* * Discard any existing clipboard data and delete the selection * handler(s) associated with that data. */ for (targetPtr = dispPtr->clipTargetPtr; targetPtr != NULL; targetPtr = nextTargetPtr) { for (cbPtr = targetPtr->firstBufferPtr; cbPtr != NULL; cbPtr = nextCbPtr) { ckfree(cbPtr->buffer); nextCbPtr = cbPtr->nextPtr; ckfree((char *) cbPtr); } nextTargetPtr = targetPtr->nextPtr; Tk_DeleteSelHandler(dispPtr->clipWindow, dispPtr->clipboardAtom, targetPtr->type); ckfree((char *) targetPtr); } dispPtr->clipTargetPtr = NULL; /* * Reclaim the clipboard selection if we lost it. */ if (!dispPtr->clipboardActive) { Tk_OwnSelection(dispPtr->clipWindow, dispPtr->clipboardAtom, ClipboardLostSel, (ClientData) dispPtr); dispPtr->clipboardActive = 1; } dispPtr->clipboardAppPtr = winPtr->mainPtr; return TCL_OK; } /* *---------------------------------------------------------------------- * * Tk_ClipboardAppend -- * * Append a buffer of data to the clipboard. The first buffer of * a given type determines the format for that type. Any successive * appends to that type must have the same format or an error will * be returned. Tk_ClipboardClear must be called before a sequence * of Tk_ClipboardAppend calls can be issued. In order to guarantee * atomicity, no event handling should occur between Tk_ClipboardClear * and the following Tk_ClipboardAppend calls. * * Results: * A standard Tcl result. If an error is returned, an error message * is left in the interp's result. * * Side effects: * The specified buffer will be copied onto the end of the clipboard. * The clipboard maintains a list of buffers which will be used to * supply the data for a selection get request. The first time a given * type is appended, Tk_ClipboardAppend will register a selection * handler of the appropriate type. * *---------------------------------------------------------------------- */ int Tk_ClipboardAppend(interp, tkwin, type, format, buffer) Tcl_Interp *interp; /* Used for error reporting. */ Tk_Window tkwin; /* Window that selects a display. */ Atom type; /* The desired conversion type for this * clipboard item, e.g. STRING or LENGTH. */ Atom format; /* Format in which the selection * information should be returned to * the requestor. */ char* buffer; /* NULL terminated string containing the data * to be added to the clipboard. */ { TkWindow *winPtr = (TkWindow *) tkwin; TkDisplay *dispPtr = winPtr->dispPtr; TkClipboardTarget *targetPtr; TkClipboardBuffer *cbPtr; /* * If this application doesn't already own the clipboard, clear * the clipboard. If we don't own the clipboard selection, claim it. */ if (dispPtr->clipboardAppPtr != winPtr->mainPtr) { Tk_ClipboardClear(interp, tkwin); } else if (!dispPtr->clipboardActive) { Tk_OwnSelection(dispPtr->clipWindow, dispPtr->clipboardAtom, ClipboardLostSel, (ClientData) dispPtr); dispPtr->clipboardActive = 1; } /* * Check to see if the specified target is already present on the * clipboard. If it isn't, we need to create a new target; otherwise, * we just append the new buffer to the clipboard list. */ for (targetPtr = dispPtr->clipTargetPtr; targetPtr != NULL; targetPtr = targetPtr->nextPtr) { if (targetPtr->type == type) break; } if (targetPtr == NULL) { targetPtr = (TkClipboardTarget*) ckalloc(sizeof(TkClipboardTarget)); targetPtr->type = type; targetPtr->format = format; targetPtr->firstBufferPtr = targetPtr->lastBufferPtr = NULL; targetPtr->nextPtr = dispPtr->clipTargetPtr; dispPtr->clipTargetPtr = targetPtr; Tk_CreateSelHandler(dispPtr->clipWindow, dispPtr->clipboardAtom, type, ClipboardHandler, (ClientData) targetPtr, format); } else if (targetPtr->format != format) { Tcl_AppendResult(interp, "format \"", Tk_GetAtomName(tkwin, format), "\" does not match current format \"", Tk_GetAtomName(tkwin, targetPtr->format),"\" for ", Tk_GetAtomName(tkwin, type), (char *) NULL); return TCL_ERROR; } /* * Append a new buffer to the buffer chain. */ cbPtr = (TkClipboardBuffer*) ckalloc(sizeof(TkClipboardBuffer)); cbPtr->nextPtr = NULL; if (targetPtr->lastBufferPtr != NULL) { targetPtr->lastBufferPtr->nextPtr = cbPtr; } else { targetPtr->firstBufferPtr = cbPtr; } targetPtr->lastBufferPtr = cbPtr; cbPtr->length = strlen(buffer); cbPtr->buffer = (char *) ckalloc((unsigned) (cbPtr->length + 1)); strcpy(cbPtr->buffer, buffer); TkSelUpdateClipboard((TkWindow*)(dispPtr->clipWindow), targetPtr); return TCL_OK; } /* *---------------------------------------------------------------------- * * Tk_ClipboardObjCmd -- * * This procedure is invoked to process the "clipboard" Tcl * command. See the user documentation for details on what * it does. * * Results: * A standard Tcl result. * * Side effects: * See the user documentation. * *---------------------------------------------------------------------- */ int Tk_ClipboardObjCmd(clientData, interp, objc, objv) ClientData clientData; /* Main window associated with * interpreter. */ Tcl_Interp *interp; /* Current interpreter. */ int objc; /* Number of arguments. */ Tcl_Obj *CONST objv[]; /* Argument strings. */ { Tk_Window tkwin = (Tk_Window) clientData; char *path = NULL; Atom selection; static CONST char *optionStrings[] = { "append", "clear", "get", NULL }; enum options { CLIPBOARD_APPEND, CLIPBOARD_CLEAR, CLIPBOARD_GET }; int index, i; if (objc < 2) { Tcl_WrongNumArgs(interp, 1, objv, "option ?arg arg ...?"); return TCL_ERROR; } if (Tcl_GetIndexFromObj(interp, objv[1], optionStrings, "option", 0, &index) != TCL_OK) { return TCL_ERROR; } switch ((enum options) index) { case CLIPBOARD_APPEND: { Atom target, format; char *targetName = NULL; char *formatName = NULL; char *string; static CONST char *appendOptionStrings[] = { "-displayof", "-format", "-type", NULL }; enum appendOptions { APPEND_DISPLAYOF, APPEND_FORMAT, APPEND_TYPE }; int subIndex, length; for (i = 2; i < objc - 1; i++) { string = Tcl_GetStringFromObj(objv[i], &length); if (string[0] != '-') { break; } /* * If the argument is "--", it signifies the end of arguments. */ if (string[1] == '-' && length == 2) { i++; break; } if (Tcl_GetIndexFromObj(interp, objv[i], appendOptionStrings, "option", 0, &subIndex) != TCL_OK) { return TCL_ERROR; } /* * Increment i so that it points to the value for the flag * instead of the flag itself. */ i++; if (i >= objc) { Tcl_AppendResult(interp, "value for \"", string, "\" missing", (char *) NULL); return TCL_ERROR; } switch ((enum appendOptions) subIndex) { case APPEND_DISPLAYOF: path = Tcl_GetString(objv[i]); break; case APPEND_FORMAT: formatName = Tcl_GetString(objv[i]); break; case APPEND_TYPE: targetName = Tcl_GetString(objv[i]); break; } } if (objc - i != 1) { Tcl_WrongNumArgs(interp, 2, objv, "?options? data"); return TCL_ERROR; } if (path != NULL) { tkwin = Tk_NameToWindow(interp, path, tkwin); } if (tkwin == NULL) { return TCL_ERROR; } if (targetName != NULL) { target = Tk_InternAtom(tkwin, targetName); } else { target = XA_STRING; } if (formatName != NULL) { format = Tk_InternAtom(tkwin, formatName); } else { format = XA_STRING; } return Tk_ClipboardAppend(interp, tkwin, target, format, Tcl_GetString(objv[i])); } case CLIPBOARD_CLEAR: { static CONST char *clearOptionStrings[] = { "-displayof", NULL }; enum clearOptions { CLEAR_DISPLAYOF }; int subIndex; if (objc != 2 && objc != 4) { Tcl_WrongNumArgs(interp, 2, objv, "?-displayof window?"); return TCL_ERROR; } if (objc == 4) { if (Tcl_GetIndexFromObj(interp, objv[2], clearOptionStrings, "option", 0, &subIndex) != TCL_OK) { return TCL_ERROR; } if ((enum clearOptions) subIndex == CLEAR_DISPLAYOF) { path = Tcl_GetString(objv[3]); } } if (path != NULL) { tkwin = Tk_NameToWindow(interp, path, tkwin); } if (tkwin == NULL) { return TCL_ERROR; } return Tk_ClipboardClear(interp, tkwin); } case CLIPBOARD_GET: { Atom target; char *targetName = NULL; Tcl_DString selBytes; int result; char *string; static CONST char *getOptionStrings[] = { "-displayof", "-type", NULL }; enum getOptions { APPEND_DISPLAYOF, APPEND_TYPE }; int subIndex; for (i = 2; i < objc; i++) { string = Tcl_GetString(objv[i]); if (string[0] != '-') { break; } if (Tcl_GetIndexFromObj(interp, objv[i], getOptionStrings, "option", 0, &subIndex) != TCL_OK) { return TCL_ERROR; } i++; if (i >= objc) { Tcl_AppendResult(interp, "value for \"", string, "\" missing", (char *) NULL); return TCL_ERROR; } switch ((enum getOptions) subIndex) { case APPEND_DISPLAYOF: path = Tcl_GetString(objv[i]); break; case APPEND_TYPE: targetName = Tcl_GetString(objv[i]); break; } } if (path != NULL) { tkwin = Tk_NameToWindow(interp, path, tkwin); } if (tkwin == NULL) { return TCL_ERROR; } selection = Tk_InternAtom(tkwin, "CLIPBOARD"); if (objc - i > 1) { Tcl_WrongNumArgs(interp, 2, objv, "?options?"); return TCL_ERROR; } else if (objc - i == 1) { target = Tk_InternAtom(tkwin, Tcl_GetString(objv[i])); } else if (targetName != NULL) { target = Tk_InternAtom(tkwin, targetName); } else { target = XA_STRING; } Tcl_DStringInit(&selBytes); result = Tk_GetSelection(interp, tkwin, selection, target, ClipboardGetProc, (ClientData) &selBytes); if (result == TCL_OK) { Tcl_DStringResult(interp, &selBytes); } else { Tcl_DStringFree(&selBytes); } return result; } } return TCL_OK; } /* *---------------------------------------------------------------------- * * TkClipCleanup -- * * This procedure is called to cleanup resources associated with * claiming clipboard ownership and for receiving selection get * results. This function is called in tkWindow.c. This has to be * called by the display cleanup function because we still need the * access display elements. * * Results: * None. * * Side effects: * Resources are freed - the clipboard may no longer be used. * *---------------------------------------------------------------------- */ void TkClipCleanup(dispPtr) TkDisplay *dispPtr; /* display associated with clipboard */ { if (dispPtr->clipWindow != NULL) { Tk_DeleteSelHandler(dispPtr->clipWindow, dispPtr->clipboardAtom, dispPtr->applicationAtom); Tk_DeleteSelHandler(dispPtr->clipWindow, dispPtr->clipboardAtom, dispPtr->windowAtom); Tk_DestroyWindow(dispPtr->clipWindow); Tcl_Release((ClientData) dispPtr->clipWindow); } } /* *---------------------------------------------------------------------- * * TkClipInit -- * * This procedure is called to initialize the window for claiming * clipboard ownership and for receiving selection get results. This * function is called from tkSelect.c as well as tkClipboard.c. * * Results: * The result is a standard Tcl return value, which is normally TCL_OK. * If an error occurs then an error message is left in the interp's * result and TCL_ERROR is returned. * * Side effects: * Sets up the clipWindow and related data structures. * *---------------------------------------------------------------------- */ int TkClipInit(interp, dispPtr) Tcl_Interp *interp; /* Interpreter to use for error * reporting. */ register TkDisplay *dispPtr;/* Display to initialize. */ { XSetWindowAttributes atts; dispPtr->clipTargetPtr = NULL; dispPtr->clipboardActive = 0; dispPtr->clipboardAppPtr = NULL; /* * Create the window used for clipboard ownership and selection retrieval, * and set up an event handler for it. */ dispPtr->clipWindow = Tk_CreateWindow(interp, (Tk_Window) NULL, "_clip", DisplayString(dispPtr->display)); if (dispPtr->clipWindow == NULL) { return TCL_ERROR; } Tcl_Preserve((ClientData) dispPtr->clipWindow); atts.override_redirect = True; Tk_ChangeWindowAttributes(dispPtr->clipWindow, CWOverrideRedirect, &atts); Tk_MakeWindowExist(dispPtr->clipWindow); if (dispPtr->multipleAtom == None) { /* * Need to invoke selection initialization to make sure that * atoms we depend on below are defined. */ TkSelInit(dispPtr->clipWindow); } /* * Create selection handlers for types TK_APPLICATION and TK_WINDOW * on this window. Can't use the default handlers for these types * because this isn't a full-fledged window. */ Tk_CreateSelHandler(dispPtr->clipWindow, dispPtr->clipboardAtom, dispPtr->applicationAtom, ClipboardAppHandler, (ClientData) dispPtr, XA_STRING); Tk_CreateSelHandler(dispPtr->clipWindow, dispPtr->clipboardAtom, dispPtr->windowAtom, ClipboardWindowHandler, (ClientData) dispPtr, XA_STRING); return TCL_OK; } /* *-------------------------------------------------------------- * * ClipboardGetProc -- * * This procedure is invoked to process pieces of the selection * as they arrive during "clipboard get" commands. * * Results: * Always returns TCL_OK. * * Side effects: * Bytes get appended to the dynamic string pointed to by the * clientData argument. * *-------------------------------------------------------------- */ /* ARGSUSED */ static int ClipboardGetProc(clientData, interp, portion) ClientData clientData; /* Dynamic string holding partially * assembled selection. */ Tcl_Interp *interp; /* Interpreter used for error * reporting (not used). */ char *portion; /* New information to be appended. */ { Tcl_DStringAppend((Tcl_DString *) clientData, portion, -1); return TCL_OK; }