+ The basic method is to look at consecutive characters and see
+ if they can form a run that can be handled as one.
+
+ Returns -1 if successful, REG_ESPACE if ran out of space. */
+
+static int
+set_image_of_range_1 (work_area, start, end, translate)
+ RE_TRANSLATE_TYPE translate;
+ struct range_table_work_area *work_area;
+ re_wchar_t start, end;
+{
+ /* `one_case' indicates a character, or a run of characters,
+ each of which is an isolate (no case-equivalents).
+ This includes all ASCII non-letters.
+
+ `two_case' indicates a character, or a run of characters,
+ each of which has two case-equivalent forms.
+ This includes all ASCII letters.
+
+ `strange' indicates a character that has more than one
+ case-equivalent. */
+
+ enum case_type {one_case, two_case, strange};
+
+ /* Describe the run that is in progress,
+ which the next character can try to extend.
+ If run_type is strange, that means there really is no run.
+ If run_type is one_case, then run_start...run_end is the run.
+ If run_type is two_case, then the run is run_start...run_end,
+ and the case-equivalents end at run_eqv_end. */
+
+ enum case_type run_type = strange;
+ int run_start, run_end, run_eqv_end;
+
+ Lisp_Object eqv_table;
+
+ if (!RE_TRANSLATE_P (translate))
+ {
+ EXTEND_RANGE_TABLE (work_area, 2);
+ work_area->table[work_area->used++] = (start);
+ work_area->table[work_area->used++] = (end);
+ return -1;
+ }
+
+ eqv_table = XCHAR_TABLE (translate)->extras[2];
+
+ for (; start <= end; start++)
+ {
+ enum case_type this_type;
+ int eqv = RE_TRANSLATE (eqv_table, start);
+ int minchar, maxchar;
+
+ /* Classify this character */
+ if (eqv == start)
+ this_type = one_case;
+ else if (RE_TRANSLATE (eqv_table, eqv) == start)
+ this_type = two_case;
+ else
+ this_type = strange;
+
+ if (start < eqv)
+ minchar = start, maxchar = eqv;
+ else
+ minchar = eqv, maxchar = start;
+
+ /* Can this character extend the run in progress? */
+ if (this_type == strange || this_type != run_type
+ || !(minchar == run_end + 1
+ && (run_type == two_case
+ ? maxchar == run_eqv_end + 1 : 1)))
+ {
+ /* No, end the run.
+ Record each of its equivalent ranges. */
+ if (run_type == one_case)
+ {
+ EXTEND_RANGE_TABLE (work_area, 2);
+ work_area->table[work_area->used++] = run_start;
+ work_area->table[work_area->used++] = run_end;
+ }
+ else if (run_type == two_case)
+ {
+ EXTEND_RANGE_TABLE (work_area, 4);
+ work_area->table[work_area->used++] = run_start;
+ work_area->table[work_area->used++] = run_end;
+ work_area->table[work_area->used++]
+ = RE_TRANSLATE (eqv_table, run_start);
+ work_area->table[work_area->used++]
+ = RE_TRANSLATE (eqv_table, run_end);
+ }
+ run_type = strange;
+ }
+
+ if (this_type == strange)
+ {
+ /* For a strange character, add each of its equivalents, one
+ by one. Don't start a range. */
+ do
+ {
+ EXTEND_RANGE_TABLE (work_area, 2);
+ work_area->table[work_area->used++] = eqv;
+ work_area->table[work_area->used++] = eqv;
+ eqv = RE_TRANSLATE (eqv_table, eqv);
+ }
+ while (eqv != start);
+ }
+
+ /* Add this char to the run, or start a new run. */
+ else if (run_type == strange)
+ {
+ /* Initialize a new range. */
+ run_type = this_type;
+ run_start = start;
+ run_end = start;
+ run_eqv_end = RE_TRANSLATE (eqv_table, run_end);
+ }
+ else
+ {
+ /* Extend a running range. */
+ run_end = minchar;
+ run_eqv_end = RE_TRANSLATE (eqv_table, run_end);
+ }
+ }
+
+ /* If a run is still in progress at the end, finish it now
+ by recording its equivalent ranges. */
+ if (run_type == one_case)
+ {
+ EXTEND_RANGE_TABLE (work_area, 2);
+ work_area->table[work_area->used++] = run_start;
+ work_area->table[work_area->used++] = run_end;
+ }
+ else if (run_type == two_case)
+ {
+ EXTEND_RANGE_TABLE (work_area, 4);
+ work_area->table[work_area->used++] = run_start;
+ work_area->table[work_area->used++] = run_end;
+ work_area->table[work_area->used++]
+ = RE_TRANSLATE (eqv_table, run_start);
+ work_area->table[work_area->used++]
+ = RE_TRANSLATE (eqv_table, run_end);
+ }
+
+ return -1;
+}
+
+#endif /* emacs */
+
+/* Record the the image of the range start..end when passed through
projects / gnulib.git / blobdiff