+\f
+/* Transpose the markers in two regions of the current buffer, and
+ adjust the ones between them if necessary (i.e.: if the regions
+ differ in size).
+
+ Traverses the entire marker list of the buffer to do so, adding an
+ appropriate amount to some, subtracting from some, and leaving the
+ rest untouched. Most of this is copied from adjust_markers in insdel.c.
+
+ It's the caller's job to see that (start1 <= end1 <= start2 <= end2). */
+
+void
+transpose_markers (start1, end1, start2, end2)
+ register int start1, end1, start2, end2;
+{
+ register int amt1, amt2, diff, mpos;
+ register Lisp_Object marker;
+
+ /* Update point as if it were a marker. */
+ if (PT < start1)
+ ;
+ else if (PT < end1)
+ TEMP_SET_PT (PT + (end2 - end1));
+ else if (PT < start2)
+ TEMP_SET_PT (PT + (end2 - start2) - (end1 - start1));
+ else if (PT < end2)
+ TEMP_SET_PT (PT - (start2 - start1));
+
+ /* We used to adjust the endpoints here to account for the gap, but that
+ isn't good enough. Even if we assume the caller has tried to move the
+ gap out of our way, it might still be at start1 exactly, for example;
+ and that places it `inside' the interval, for our purposes. The amount
+ of adjustment is nontrivial if there's a `denormalized' marker whose
+ position is between GPT and GPT + GAP_SIZE, so it's simpler to leave
+ the dirty work to Fmarker_position, below. */
+
+ /* The difference between the region's lengths */
+ diff = (end2 - start2) - (end1 - start1);
+
+ /* For shifting each marker in a region by the length of the other
+ * region plus the distance between the regions.
+ */
+ amt1 = (end2 - start2) + (start2 - end1);
+ amt2 = (end1 - start1) + (start2 - end1);
+
+ for (marker = current_buffer->markers; !NILP (marker);
+ marker = XMARKER (marker)->chain)
+ {
+ mpos = Fmarker_position (marker);
+ if (mpos >= start1 && mpos < end2)
+ {
+ if (mpos < end1)
+ mpos += amt1;
+ else if (mpos < start2)
+ mpos += diff;
+ else
+ mpos -= amt2;
+ if (mpos > GPT) mpos += GAP_SIZE;
+ XMARKER (marker)->bufpos = mpos;
+ }
+ }
+}
+
+DEFUN ("transpose-regions", Ftranspose_regions, Stranspose_regions, 4, 5, 0,
+ "Transpose region START1 to END1 with START2 to END2.\n\
+The regions may not be overlapping, because the size of the buffer is\n\
+never changed in a transposition.\n\
+\n\
+Optional fifth arg LEAVE_MARKERS, if non-nil, means don't transpose\n\
+any markers that happen to be located in the regions.\n\
+\n\
+Transposing beyond buffer boundaries is an error.")
+ (startr1, endr1, startr2, endr2, leave_markers)
+ Lisp_Object startr1, endr1, startr2, endr2, leave_markers;
+{
+ register int start1, end1, start2, end2,
+ gap, len1, len_mid, len2;
+ unsigned char *start1_addr, *start2_addr, *temp;
+
+#ifdef USE_TEXT_PROPERTIES
+ INTERVAL cur_intv, tmp_interval1, tmp_interval_mid, tmp_interval2;
+ cur_intv = current_buffer->intervals;
+#endif /* USE_TEXT_PROPERTIES */
+
+ validate_region (&startr1, &endr1);
+ validate_region (&startr2, &endr2);
+
+ start1 = XFASTINT (startr1);
+ end1 = XFASTINT (endr1);
+ start2 = XFASTINT (startr2);
+ end2 = XFASTINT (endr2);
+ gap = GPT;
+
+ /* Swap the regions if they're reversed. */
+ if (start2 < end1)
+ {
+ register int glumph = start1;
+ start1 = start2;
+ start2 = glumph;
+ glumph = end1;
+ end1 = end2;
+ end2 = glumph;
+ }
+
+ len1 = end1 - start1;
+ len2 = end2 - start2;
+
+ if (start2 < end1)
+ error ("transposed regions not properly ordered");
+ else if (start1 == end1 || start2 == end2)
+ error ("transposed region may not be of length 0");
+
+ /* The possibilities are:
+ 1. Adjacent (contiguous) regions, or separate but equal regions
+ (no, really equal, in this case!), or
+ 2. Separate regions of unequal size.
+
+ The worst case is usually No. 2. It means that (aside from
+ potential need for getting the gap out of the way), there also
+ needs to be a shifting of the text between the two regions. So
+ if they are spread far apart, we are that much slower... sigh. */
+
+ /* It must be pointed out that the really studly thing to do would
+ be not to move the gap at all, but to leave it in place and work
+ around it if necessary. This would be extremely efficient,
+ especially considering that people are likely to do
+ transpositions near where they are working interactively, which
+ is exactly where the gap would be found. However, such code
+ would be much harder to write and to read. So, if you are
+ reading this comment and are feeling squirrely, by all means have
+ a go! I just didn't feel like doing it, so I will simply move
+ the gap the minimum distance to get it out of the way, and then
+ deal with an unbroken array. */
+
+ /* Make sure the gap won't interfere, by moving it out of the text
+ we will operate on. */
+ if (start1 < gap && gap < end2)
+ {
+ if (gap - start1 < end2 - gap)
+ move_gap (start1);
+ else
+ move_gap (end2);
+ }
+
+ /* Hmmm... how about checking to see if the gap is large
+ enough to use as the temporary storage? That would avoid an
+ allocation... interesting. Later, don't fool with it now. */
+
+ /* Working without memmove, for portability (sigh), so must be
+ careful of overlapping subsections of the array... */
+
+ if (end1 == start2) /* adjacent regions */
+ {
+ modify_region (current_buffer, start1, end2);
+ record_change (start1, len1 + len2);
+
+#ifdef USE_TEXT_PROPERTIES
+ tmp_interval1 = copy_intervals (cur_intv, start1, len1);
+ tmp_interval2 = copy_intervals (cur_intv, start2, len2);
+ Fset_text_properties (start1, end2, Qnil, Qnil);
+#endif /* USE_TEXT_PROPERTIES */
+
+ /* First region smaller than second. */
+ if (len1 < len2)
+ {
+ /* We use alloca only if it is small,
+ because we want to avoid stack overflow. */
+ if (len2 > 20000)
+ temp = (unsigned char *) xmalloc (len2);
+ else
+ temp = (unsigned char *) alloca (len2);
+
+ /* Don't precompute these addresses. We have to compute them
+ at the last minute, because the relocating allocator might
+ have moved the buffer around during the xmalloc. */
+ start1_addr = BUF_CHAR_ADDRESS (current_buffer, start1);
+ start2_addr = BUF_CHAR_ADDRESS (current_buffer, start2);
+
+ bcopy (start2_addr, temp, len2);
+ bcopy (start1_addr, start1_addr + len2, len1);
+ bcopy (temp, start1_addr, len2);
+ if (len2 > 20000)
+ free (temp);
+ }
+ else
+ /* First region not smaller than second. */
+ {
+ if (len1 > 20000)
+ temp = (unsigned char *) xmalloc (len1);
+ else
+ temp = (unsigned char *) alloca (len1);
+ start1_addr = BUF_CHAR_ADDRESS (current_buffer, start1);
+ start2_addr = BUF_CHAR_ADDRESS (current_buffer, start2);
+ bcopy (start1_addr, temp, len1);
+ bcopy (start2_addr, start1_addr, len2);
+ bcopy (temp, start1_addr + len2, len1);
+ if (len1 > 20000)
+ free (temp);
+ }
+#ifdef USE_TEXT_PROPERTIES
+ graft_intervals_into_buffer (tmp_interval1, start1 + len2,
+ len1, current_buffer, 0);
+ graft_intervals_into_buffer (tmp_interval2, start1,
+ len2, current_buffer, 0);
+#endif /* USE_TEXT_PROPERTIES */
+ }
+ /* Non-adjacent regions, because end1 != start2, bleagh... */
+ else
+ {
+ if (len1 == len2)
+ /* Regions are same size, though, how nice. */
+ {
+ modify_region (current_buffer, start1, end1);
+ modify_region (current_buffer, start2, end2);
+ record_change (start1, len1);
+ record_change (start2, len2);
+#ifdef USE_TEXT_PROPERTIES
+ tmp_interval1 = copy_intervals (cur_intv, start1, len1);
+ tmp_interval2 = copy_intervals (cur_intv, start2, len2);
+ Fset_text_properties (start1, end1, Qnil, Qnil);
+ Fset_text_properties (start2, end2, Qnil, Qnil);
+#endif /* USE_TEXT_PROPERTIES */
+
+ if (len1 > 20000)
+ temp = (unsigned char *) xmalloc (len1);
+ else
+ temp = (unsigned char *) alloca (len1);
+ start1_addr = BUF_CHAR_ADDRESS (current_buffer, start1);
+ start2_addr = BUF_CHAR_ADDRESS (current_buffer, start2);
+ bcopy (start1_addr, temp, len1);
+ bcopy (start2_addr, start1_addr, len2);
+ bcopy (temp, start2_addr, len1);
+ if (len1 > 20000)
+ free (temp);
+#ifdef USE_TEXT_PROPERTIES
+ graft_intervals_into_buffer (tmp_interval1, start2,
+ len1, current_buffer, 0);
+ graft_intervals_into_buffer (tmp_interval2, start1,
+ len2, current_buffer, 0);
+#endif /* USE_TEXT_PROPERTIES */
+ }
+
+ else if (len1 < len2) /* Second region larger than first */
+ /* Non-adjacent & unequal size, area between must also be shifted. */
+ {
+ len_mid = start2 - end1;
+ modify_region (current_buffer, start1, end2);
+ record_change (start1, (end2 - start1));
+#ifdef USE_TEXT_PROPERTIES
+ tmp_interval1 = copy_intervals (cur_intv, start1, len1);
+ tmp_interval_mid = copy_intervals (cur_intv, end1, len_mid);
+ tmp_interval2 = copy_intervals (cur_intv, start2, len2);
+ Fset_text_properties (start1, end2, Qnil, Qnil);
+#endif /* USE_TEXT_PROPERTIES */
+
+ /* holds region 2 */
+ if (len2 > 20000)
+ temp = (unsigned char *) xmalloc (len2);
+ else
+ temp = (unsigned char *) alloca (len2);
+ start1_addr = BUF_CHAR_ADDRESS (current_buffer, start1);
+ start2_addr = BUF_CHAR_ADDRESS (current_buffer, start2);
+ bcopy (start2_addr, temp, len2);
+ bcopy (start1_addr, start1_addr + len_mid + len2, len1);
+ safe_bcopy (start1_addr + len1, start1_addr + len2, len_mid);
+ bcopy (temp, start1_addr, len2);
+ if (len2 > 20000)
+ free (temp);
+#ifdef USE_TEXT_PROPERTIES
+ graft_intervals_into_buffer (tmp_interval1, end2 - len1,
+ len1, current_buffer, 0);
+ graft_intervals_into_buffer (tmp_interval_mid, start1 + len2,
+ len_mid, current_buffer, 0);
+ graft_intervals_into_buffer (tmp_interval2, start1,
+ len2, current_buffer, 0);
+#endif /* USE_TEXT_PROPERTIES */
+ }
+ else
+ /* Second region smaller than first. */
+ {
+ len_mid = start2 - end1;
+ record_change (start1, (end2 - start1));
+ modify_region (current_buffer, start1, end2);
+
+#ifdef USE_TEXT_PROPERTIES
+ tmp_interval1 = copy_intervals (cur_intv, start1, len1);
+ tmp_interval_mid = copy_intervals (cur_intv, end1, len_mid);
+ tmp_interval2 = copy_intervals (cur_intv, start2, len2);
+ Fset_text_properties (start1, end2, Qnil, Qnil);
+#endif /* USE_TEXT_PROPERTIES */
+
+ /* holds region 1 */
+ if (len1 > 20000)
+ temp = (unsigned char *) xmalloc (len1);
+ else
+ temp = (unsigned char *) alloca (len1);
+ start1_addr = BUF_CHAR_ADDRESS (current_buffer, start1);
+ start2_addr = BUF_CHAR_ADDRESS (current_buffer, start2);
+ bcopy (start1_addr, temp, len1);
+ bcopy (start2_addr, start1_addr, len2);
+ bcopy (start1_addr + len1, start1_addr + len2, len_mid);
+ bcopy (temp, start1_addr + len2 + len_mid, len1);
+ if (len1 > 20000)
+ free (temp);
+#ifdef USE_TEXT_PROPERTIES
+ graft_intervals_into_buffer (tmp_interval1, end2 - len1,
+ len1, current_buffer, 0);
+ graft_intervals_into_buffer (tmp_interval_mid, start1 + len2,
+ len_mid, current_buffer, 0);
+ graft_intervals_into_buffer (tmp_interval2, start1,
+ len2, current_buffer, 0);
+#endif /* USE_TEXT_PROPERTIES */
+ }
+ }
+
+ /* todo: this will be slow, because for every transposition, we
+ traverse the whole friggin marker list. Possible solutions:
+ somehow get a list of *all* the markers across multiple
+ transpositions and do it all in one swell phoop. Or maybe modify
+ Emacs' marker code to keep an ordered list or tree. This might
+ be nicer, and more beneficial in the long run, but would be a
+ bunch of work. Plus the way they're arranged now is nice. */
+ if (NILP (leave_markers))
+ {
+ transpose_markers (start1, end1, start2, end2);
+ fix_overlays_in_range (start1, end2);
+ }
+
+ return Qnil;
+}
HCoop / bpt / emacs.git / blobdiff