/* 16-bit Windows Selection processing for emacs on MS-Windows Copyright (C) 1996-1997, 2001-2023 Free Software Foundation, Inc. Author: Dale P. Smith This file is part of GNU Emacs. GNU Emacs is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. GNU Emacs is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GNU Emacs. If not, see . */ /* These functions work by using WinOldAp interface. WinOldAp (WINOLDAP.MOD) is a Microsoft Windows extension supporting "old" (character-mode) application access to Dynamic Data Exchange, menus, and the Windows clipboard. */ /* Adapted to DJGPP by Eli Zaretskii */ #ifdef MSDOS #include #include #include #include #include "lisp.h" #include "dispextern.h" /* frame.h seems to want this */ #include "frame.h" /* Need this to get the X window of selected_frame */ #include "blockinput.h" #include "character.h" #include "buffer.h" #include "coding.h" #include "composite.h" /* If ever some function outside this file will need to call any clipboard-related function, the following prototypes and constants should be put on a header file. Right now, nobody else uses them. */ #define CF_TEXT 0x01 #define CF_BITMAP 0x02 #define CF_METAFILE 0x03 #define CF_SYLK 0x04 #define CF_DIF 0x05 #define CF_TIFF 0x06 #define CF_OEMTEXT 0x07 #define CF_DIBBITMAP 0x08 #define CF_WINWRITE 0x80 #define CF_DSPTEXT 0x81 #define CF_DSPBITMAP 0x82 unsigned identify_winoldap_version (void); unsigned open_clipboard (void); unsigned empty_clipboard (void); unsigned set_clipboard_data (unsigned, void *, unsigned, int); unsigned get_clipboard_data_size (unsigned); unsigned get_clipboard_data (unsigned, void *, unsigned, int); unsigned close_clipboard (void); unsigned clipboard_compact (unsigned); /* The segment address and the size of the buffer in low memory used to move data between us and WinOldAp module. */ static struct { unsigned long size; unsigned short rm_segment; } clipboard_xfer_buf_info; /* The last text we put into the clipboard. This is used to prevent passing back our own text from the clipboard, instead of using the kill ring. The former is undesirable because the clipboard data could be MULEtilated by inappropriately chosen (next-)selection-coding-system. For this reason, we must store the text *after* it was encoded/Unix-to-DOS-converted. */ static unsigned char *last_clipboard_text; /* The size of allocated storage for storing the clipboard data. */ static size_t clipboard_storage_size; /* C functions to access the Windows 3.1x clipboard from DOS apps. The information was obtained from the Microsoft Knowledge Base, article Q67675 and can be found at: [broken link -- SK 2021-09-27] http://www.microsoft.com/kb/developr/win_dk/q67675.htm */ /* See also Ralf Brown's Interrupt List. I also seem to remember reading about this in Dr. Dobbs Journal a while ago, but if you knew my memory... :-) Dale P. Smith */ /* Return the WinOldAp support version, or 0x1700 if not supported. */ unsigned identify_winoldap_version (void) { __dpmi_regs regs; /* Calls Int 2Fh/AX=1700h Return Values AX == 1700H: Clipboard functions not available <> 1700H: AL = Major version number AH = Minor version number */ regs.x.ax = 0x1700; __dpmi_int (0x2f, ®s); return regs.x.ax; } /* Open the clipboard, return non-zero if successful. */ unsigned open_clipboard (void) { __dpmi_regs regs; /* Is WINOLDAP supported? */ /* Kludge alert!! If WinOldAp is not supported, we return a 0, which is the same as ``Clipboard already open''. Currently, this is taken as an error by all the functions that use `open_clipboard', but if somebody someday will use that ``open'' clipboard, they will have interesting time debugging it... */ if (identify_winoldap_version () == 0x1700) return 0; /* Calls Int 2Fh/AX=1701h Return Values AX == 0: Clipboard already open <> 0: Clipboard opened */ regs.x.ax = 0x1701; __dpmi_int (0x2f, ®s); return regs.x.ax; } /* Empty clipboard, return non-zero if successful. */ unsigned empty_clipboard (void) { __dpmi_regs regs; /* Calls Int 2Fh/AX=1702h Return Values AX == 0: Error occurred <> 0: OK, Clipboard emptied */ regs.x.ax = 0x1702; __dpmi_int (0x2f, ®s); return regs.x.ax; } /* Ensure we have a buffer in low memory with enough memory for data of size WANT_SIZE. Return the linear address of the buffer. */ static unsigned long alloc_xfer_buf (unsigned want_size) { __dpmi_regs regs; /* If the usual DJGPP transfer buffer is large enough, use that. */ if (want_size <= _go32_info_block.size_of_transfer_buffer) return __tb & 0xfffff; /* Don't even try to allocate more than 1MB of memory: DOS cannot possibly handle that (it will overflow the BX register below). */ if (want_size > 0xfffff) return 0; /* Need size rounded up to the nearest paragraph, and in paragraph units (1 paragraph = 16 bytes). */ clipboard_xfer_buf_info.size = (want_size + 15) >> 4; /* The NT DPMI host crashes us if we free DOS memory via the DPMI service. Work around by calling DOS allocate/free block. */ regs.h.ah = 0x48; regs.x.bx = clipboard_xfer_buf_info.size; __dpmi_int (0x21, ®s); if (regs.x.flags & 1) { clipboard_xfer_buf_info.size = 0; return 0; } clipboard_xfer_buf_info.rm_segment = regs.x.ax; return (((int)clipboard_xfer_buf_info.rm_segment) << 4) & 0xfffff; } /* Free our clipboard buffer. We always free it after use, because keeping it leaves less free conventional memory for subprocesses. The clipboard buffer tends to be large in size, because for small clipboard data sizes we use the DJGPP transfer buffer. */ static void free_xfer_buf (void) { /* If the size is 0, we used DJGPP transfer buffer, so don't free. */ if (clipboard_xfer_buf_info.size) { __dpmi_regs regs; /* The NT DPMI host crashes us if we free DOS memory via the DPMI service. Work around by calling DOS free block. */ regs.h.ah = 0x49; regs.x.es = clipboard_xfer_buf_info.rm_segment; __dpmi_int (0x21, ®s); clipboard_xfer_buf_info.size = 0; } } /* Copy data into the clipboard, return zero if successful. */ unsigned set_clipboard_data (unsigned Format, void *Data, unsigned Size, int Raw) { __dpmi_regs regs; unsigned truelen; unsigned long xbuf_addr, buf_offset; unsigned char *dp = Data, *dstart = dp; if (Format != CF_OEMTEXT) return 3; /* need to know final size after '\r' chars are inserted (the standard CF_OEMTEXT clipboard format uses CRLF line endings, while Emacs uses just LF internally). */ truelen = Size + 1; /* +1 for the terminating null */ if (!Raw) { /* avoid using strchr because it recomputes the length every time */ while ((dp = memchr (dp, '\n', Size - (dp - dstart))) != 0) { truelen++; dp++; } } if (clipboard_compact (truelen) < truelen) return 1; if ((xbuf_addr = alloc_xfer_buf (truelen)) == 0) return 1; /* Move the buffer into the low memory, convert LF into CR-LF if needed. */ if (Raw) { dosmemput (Data, Size, xbuf_addr); /* Terminate with a null, otherwise Windows does strange things when the text size is an integral multiple of 32 bytes. */ _farpokeb (_dos_ds, xbuf_addr + Size, '\0'); } else { dp = Data; buf_offset = xbuf_addr; _farsetsel (_dos_ds); while (Size--) { /* Don't allow them to put binary data into the clipboard, since it will cause yanked data to be truncated at the first null. */ if (*dp == '\0') return 2; if (*dp == '\n') _farnspokeb (buf_offset++, '\r'); _farnspokeb (buf_offset++, *dp++); } /* Terminate with a null, otherwise Windows does strange things when the text size is an integral multiple of 32 bytes. */ _farnspokeb (buf_offset, '\0'); } /* Stash away the data we are about to put into the clipboard, so we could later check inside get_clipboard_data whether the clipboard still holds our data. */ if (clipboard_storage_size < truelen) { clipboard_storage_size = truelen + 100; last_clipboard_text = (char *) xrealloc (last_clipboard_text, clipboard_storage_size); } if (last_clipboard_text) dosmemget (xbuf_addr, truelen, last_clipboard_text); /* Calls Int 2Fh/AX=1703h with: DX = WinOldAp-Supported Clipboard format ES:BX = Pointer to data SI:CX = Size of data in bytes Return Values AX == 0: Error occurred <> 0: OK. Data copied into the Clipboard. */ regs.x.ax = 0x1703; regs.x.dx = Format; regs.x.si = truelen >> 16; regs.x.cx = truelen & 0xffff; regs.x.es = xbuf_addr >> 4; regs.x.bx = xbuf_addr & 15; __dpmi_int (0x2f, ®s); free_xfer_buf (); /* If the above failed, invalidate the local copy of the clipboard. */ if (regs.x.ax == 0) *last_clipboard_text = '\0'; /* Zero means success, otherwise (1, 2, or 3) it's an error. */ return regs.x.ax > 0 ? 0 : 3; } /* Return the size of the clipboard data of format FORMAT. */ unsigned get_clipboard_data_size (unsigned Format) { __dpmi_regs regs; /* Calls Int 2Fh/AX=1704h with: DX = WinOldAp-Supported Clipboard format Return Values DX:AX == Size of the data in bytes, including any headers. == 0 If data in this format is not in the clipboard. */ regs.x.ax = 0x1704; regs.x.dx = Format; __dpmi_int (0x2f, ®s); return ( (((unsigned)regs.x.dx) << 16) | regs.x.ax); } /* Get clipboard data, return its length. Warning: this doesn't check whether DATA has enough space to hold SIZE bytes. */ unsigned get_clipboard_data (unsigned Format, void *Data, unsigned Size, int Raw) { __dpmi_regs regs; unsigned long xbuf_addr; unsigned char *dp = Data; if (Format != CF_OEMTEXT) return 0; if (Size == 0) return 0; if ((xbuf_addr = alloc_xfer_buf (Size)) == 0) return 0; /* Calls Int 2Fh/AX=1705h with: DX = WinOldAp-Supported Clipboard format ES:BX = Pointer to data buffer to hold data Return Values AX == 0: Error occurred (or data in this format is not in the clipboard) <> 0: OK */ regs.x.ax = 0x1705; regs.x.dx = Format; regs.x.es = xbuf_addr >> 4; regs.x.bx = xbuf_addr & 15; __dpmi_int (0x2f, ®s); if (regs.x.ax != 0) { unsigned char null_char = '\0'; unsigned long xbuf_beg = xbuf_addr; /* If last_clipboard_text is NULL, we don't want to slow down the next loop by an additional test. */ register unsigned char *lcdp = last_clipboard_text == NULL ? &null_char : last_clipboard_text; /* Copy data from low memory, remove CR characters before LF if needed. */ _farsetsel (_dos_ds); while (Size--) { register unsigned char c = _farnspeekb (xbuf_addr++); if (*lcdp == c) lcdp++; if ((*dp++ = c) == '\r' && !Raw && _farnspeekb (xbuf_addr) == '\n') { dp--; *dp++ = '\n'; xbuf_addr++; if (*lcdp == '\n') lcdp++; } /* Windows reportedly rounds up the size of clipboard data (passed in SIZE) to a multiple of 32, and removes trailing spaces from each line without updating SIZE. We therefore bail out when we see the first null character. */ else if (c == '\0') break; } /* If the text in clipboard is identical to what we put there last time set_clipboard_data was called, pretend there's no data in the clipboard. This is so we don't pass our own text from the clipboard (which might be troublesome if the killed text includes null characters). */ if (last_clipboard_text && xbuf_addr - xbuf_beg == (long)(lcdp - last_clipboard_text)) dp = (unsigned char *)Data + 1; } free_xfer_buf (); return (unsigned) (dp - (unsigned char *)Data - 1); } /* Close clipboard, return non-zero if successful. */ unsigned close_clipboard (void) { __dpmi_regs regs; /* Calls Int 2Fh/AX=1708h Return Values AX == 0: Error occurred <> 0: OK */ regs.x.ax = 0x1708; __dpmi_int (0x2f, ®s); return regs.x.ax; } /* Compact clipboard data so that at least SIZE bytes is available. */ unsigned clipboard_compact (unsigned Size) { __dpmi_regs regs; /* Calls Int 2Fh/AX=1709H with: SI:CX = Desired memory size in bytes. Return Values DX:AX == Number of bytes of largest block of free memory. == 0 if error or no memory */ regs.x.ax = 0x1709; regs.x.si = Size >> 16; regs.x.cx = Size & 0xffff; __dpmi_int (0x2f, ®s); return ((unsigned)regs.x.dx << 16) | regs.x.ax; } static char no_mem_msg[] = "(Not enough DOS memory to put saved text into clipboard.)"; static char binary_msg[] = "(Binary characters in saved text; clipboard data not set.)"; static char system_error_msg[] = "(Clipboard interface failure; clipboard data not set.)"; DEFUN ("w16-set-clipboard-data", Fw16_set_clipboard_data, Sw16_set_clipboard_data, 1, 2, 0, doc: /* This sets the clipboard data to the given text. */) (Lisp_Object string, Lisp_Object frame) { unsigned ok = 1, put_status = 0; int nbytes, no_crlf_conversion; unsigned char *src, *dst = NULL; CHECK_STRING (string); if (!FRAME_MSDOS_P (decode_live_frame (frame))) goto done; block_input (); if (!open_clipboard ()) goto error; nbytes = SBYTES (string); src = SDATA (string); /* Do we need to encode this text? */ for (dst = src; dst < src + nbytes; dst++) { if (*dst == '\0' || *dst >= 0x80) break; } if (dst >= src + nbytes) { /* No multibyte characters in text. We need not encode it, but we will have to convert it to DOS CR-LF style. */ no_crlf_conversion = 0; Vlast_coding_system_used = Qraw_text; dst = NULL; /* so we don't try to free a random pointer */ } else { /* We must encode contents of STRING according to what clipboard-coding-system specifies. */ struct coding_system coding; Lisp_Object coding_system = NILP (Vnext_selection_coding_system) ? Vselection_coding_system : Vnext_selection_coding_system; setup_coding_system (Fcheck_coding_system (coding_system), &coding); coding.dst_bytes = nbytes * 4; coding.destination = xmalloc (coding.dst_bytes); Vnext_selection_coding_system = Qnil; coding.mode |= CODING_MODE_LAST_BLOCK; dst = coding.destination; encode_coding_object (&coding, string, 0, 0, SCHARS (string), nbytes, Qnil); no_crlf_conversion = 1; nbytes = coding.produced; Vlast_coding_system_used = CODING_ID_NAME (coding.id); src = dst; } ok = empty_clipboard () && ((put_status = set_clipboard_data (CF_OEMTEXT, src, nbytes, no_crlf_conversion)) == 0); if (!no_crlf_conversion) close_clipboard (); if (ok) goto unblock; error: ok = 0; unblock: xfree (dst); unblock_input (); /* Notify user if the text is too large to fit into DOS memory. (This will happen somewhere after 600K bytes (470K in DJGPP v1.x), depending on user system configuration.) If we just silently fail the function, people might wonder why their text sometimes doesn't make it to the clipboard. */ if (put_status) { switch (put_status) { case 1: message3 (make_unibyte_string (no_mem_msg, sizeof (no_mem_msg) - 1)); break; case 2: message3 (make_unibyte_string (binary_msg, sizeof (binary_msg) - 1)); break; case 3: message3 (make_unibyte_string (system_error_msg, sizeof (system_error_msg) - 1)); break; } sit_for (make_fixnum (2), 0, 2); } done: return (ok && put_status == 0 ? string : Qnil); } DEFUN ("w16-get-clipboard-data", Fw16_get_clipboard_data, Sw16_get_clipboard_data, 0, 1, 0, doc: /* This gets the clipboard data in text format. */) (Lisp_Object frame) { unsigned data_size, truelen; unsigned char *htext = NULL; Lisp_Object ret = Qnil; int require_decoding = 0; if (!FRAME_MSDOS_P (decode_live_frame (frame))) goto done; block_input (); if (!open_clipboard ()) goto unblock; if ((data_size = get_clipboard_data_size (CF_OEMTEXT)) == 0 || (htext = xmalloc (data_size)) == 0) goto closeclip; /* need to know final size after '\r' chars are removed because we can't change the string size manually, and doing an extra copy is silly */ if ((truelen = get_clipboard_data (CF_OEMTEXT, htext, data_size, 0)) == 0) goto closeclip; /* Do we need to decode it? */ { /* If the clipboard data contains any 8-bit Latin-1 code, we need to decode it. */ int i; for (i = 0; i < truelen; i++) { if (htext[i] >= 0x80) { require_decoding = 1; break; } } } if (require_decoding) { struct coding_system coding; Lisp_Object coding_system = Vnext_selection_coding_system; truelen = get_clipboard_data (CF_OEMTEXT, htext, data_size, 1); if (NILP (coding_system)) coding_system = Vselection_coding_system; setup_coding_system (Fcheck_coding_system (coding_system), &coding); coding.source = htext; coding.mode |= CODING_MODE_LAST_BLOCK; /* We explicitly disable composition handling because selection data should not contain any composition sequence. */ coding.common_flags &= ~CODING_ANNOTATION_MASK; decode_coding_object (&coding, Qnil, 0, 0, truelen, truelen, Qt); ret = coding.dst_object; Vlast_coding_system_used = CODING_ID_NAME (coding.id); } else { ret = make_unibyte_string ((char *) htext, truelen); Vlast_coding_system_used = Qraw_text; } xfree (htext); Vnext_selection_coding_system = Qnil; closeclip: close_clipboard (); unblock: unblock_input (); done: return (ret); } /* Support checking for a clipboard selection. */ DEFUN ("w16-selection-exists-p", Fw16_selection_exists_p, Sw16_selection_exists_p, 0, 2, 0, doc: /* Whether there is an owner for the given X selection. SELECTION should be the name of the selection in question, typically one of the symbols `PRIMARY', `SECONDARY', or `CLIPBOARD'. (X expects these literal upper-case names.) The symbol nil is the same as `PRIMARY', and t is the same as `SECONDARY'. TERMINAL should be a terminal object or a frame specifying the X server to query. If omitted or nil, that stands for the selected frame's display, or the first available X display. */) (Lisp_Object selection, Lisp_Object terminal) { CHECK_SYMBOL (selection); /* Return nil for SECONDARY selection. For PRIMARY (or nil) selection, check if there is some text on the kill-ring; for CLIPBOARD, check if the clipboard currently has valid text format contents. The test for killed text on the kill-ring emulates the Emacs behavior on X, where killed text is also put into X selection by the X interface code. (On MSDOS, killed text is only put into the clipboard if we run under Windows, so we cannot check the clipboard alone.) */ if ((NILP (selection) || EQ (selection, QPRIMARY)) && ! NILP (Fsymbol_value (Fintern_soft (build_string ("kill-ring"), Qnil)))) return Qt; if (EQ (selection, QCLIPBOARD)) { Lisp_Object val = Qnil; if (open_clipboard ()) { if (get_clipboard_data_size (CF_OEMTEXT)) val = Qt; close_clipboard (); } return val; } return Qnil; } void syms_of_win16select (void) { defsubr (&Sw16_set_clipboard_data); defsubr (&Sw16_get_clipboard_data); defsubr (&Sw16_selection_exists_p); DEFVAR_LISP ("selection-coding-system", Vselection_coding_system, doc: /* SKIP: real doc in select.el. */); Vselection_coding_system = intern ("iso-latin-1-dos"); DEFVAR_LISP ("next-selection-coding-system", Vnext_selection_coding_system, doc: /* SKIP: real doc in select.el. */); Vnext_selection_coding_system = Qnil; DEFSYM (QCLIPBOARD, "CLIPBOARD"); } #endif /* MSDOS */