+static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
+{
+ if (!DIFF_FILE_VALID(one)) {
+ mf->ptr = (char *)""; /* does not matter */
+ mf->size = 0;
+ return 0;
+ }
+ else if (diff_populate_filespec(one, 0))
+ return -1;
+ mf->ptr = one->data;
+ mf->size = one->size;
+ return 0;
+}
+
+static int count_trailing_blank(mmfile_t *mf, unsigned ws_rule)
+{
+ char *ptr = mf->ptr;
+ long size = mf->size;
+ int cnt = 0;
+
+ if (!size)
+ return cnt;
+ ptr += size - 1; /* pointing at the very end */
+ if (*ptr != '\n')
+ ; /* incomplete line */
+ else
+ ptr--; /* skip the last LF */
+ while (mf->ptr < ptr) {
+ char *prev_eol;
+ for (prev_eol = ptr; mf->ptr <= prev_eol; prev_eol--)
+ if (*prev_eol == '\n')
+ break;
+ if (!ws_blank_line(prev_eol + 1, ptr - prev_eol, ws_rule))
+ break;
+ cnt++;
+ ptr = prev_eol - 1;
+ }
+ return cnt;
+}
+
+static void check_blank_at_eof(mmfile_t *mf1, mmfile_t *mf2,
+ struct emit_callback *ecbdata)
+{
+ int l1, l2, at;
+ unsigned ws_rule = ecbdata->ws_rule;
+ l1 = count_trailing_blank(mf1, ws_rule);
+ l2 = count_trailing_blank(mf2, ws_rule);
+ if (l2 <= l1) {
+ ecbdata->blank_at_eof_in_preimage = 0;
+ ecbdata->blank_at_eof_in_postimage = 0;
+ return;
+ }
+ at = count_lines(mf1->ptr, mf1->size);
+ ecbdata->blank_at_eof_in_preimage = (at - l1) + 1;
+
+ at = count_lines(mf2->ptr, mf2->size);
+ ecbdata->blank_at_eof_in_postimage = (at - l2) + 1;
+}
+
+static void emit_line(FILE *file, const char *set, const char *reset, const char *line, int len)
+{
+ int has_trailing_newline, has_trailing_carriage_return;
+
+ has_trailing_newline = (len > 0 && line[len-1] == '\n');
+ if (has_trailing_newline)
+ len--;
+ has_trailing_carriage_return = (len > 0 && line[len-1] == '\r');
+ if (has_trailing_carriage_return)
+ len--;
+
+ fputs(set, file);
+ fwrite(line, len, 1, file);
+ fputs(reset, file);
+ if (has_trailing_carriage_return)
+ fputc('\r', file);
+ if (has_trailing_newline)
+ fputc('\n', file);
+}
+
+static int new_blank_line_at_eof(struct emit_callback *ecbdata, const char *line, int len)
+{
+ if (!((ecbdata->ws_rule & WS_BLANK_AT_EOF) &&
+ ecbdata->blank_at_eof_in_preimage &&
+ ecbdata->blank_at_eof_in_postimage &&
+ ecbdata->blank_at_eof_in_preimage <= ecbdata->lno_in_preimage &&
+ ecbdata->blank_at_eof_in_postimage <= ecbdata->lno_in_postimage))
+ return 0;
+ return ws_blank_line(line + 1, len - 1, ecbdata->ws_rule);
+}
+
+static void emit_add_line(const char *reset, struct emit_callback *ecbdata, const char *line, int len)
+{
+ const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
+ const char *set = diff_get_color(ecbdata->color_diff, DIFF_FILE_NEW);
+
+ if (!*ws)
+ emit_line(ecbdata->file, set, reset, line, len);
+ else if (new_blank_line_at_eof(ecbdata, line, len))
+ /* Blank line at EOF - paint '+' as well */
+ emit_line(ecbdata->file, ws, reset, line, len);
+ else {
+ /* Emit just the prefix, then the rest. */
+ emit_line(ecbdata->file, set, reset, line, 1);
+ ws_check_emit(line + 1, len - 1, ecbdata->ws_rule,
+ ecbdata->file, set, reset, ws);
+ }
+}
+