diff options
Diffstat (limited to 'buffer.c')
| -rw-r--r-- | buffer.c | 75 |
1 files changed, 45 insertions, 30 deletions
@@ -536,26 +536,37 @@ static void buffer_remove_last_edit_if_empty(TextBuffer *buffer) { } } -// grow capacity of line to at least minimum_capacity // returns true if allocation was succesful -static Status buffer_line_set_min_capacity(TextBuffer *buffer, Line *line, u32 minimum_capacity) { - while (line->capacity < minimum_capacity) { - // double capacity of line - u32 new_capacity = line->capacity == 0 ? 4 : line->capacity * 2; - if (new_capacity < line->capacity) { - // this could only happen if line->capacity * 2 overflows. - buffer_seterr(buffer, "Line %td is too large.", line - buffer->lines); - return false; +static Status buffer_line_set_len(TextBuffer *buffer, Line *line, u32 new_len) { + if (new_len >= 8) { + u32 curr_capacity = (u32)1 << (32 - util_count_leading_zeroes(line->len)); + + if (new_len >= curr_capacity) { + u8 leading_zeroes = util_count_leading_zeroes(new_len); + if (leading_zeroes == 0) { + // this line is too big + return false; + } else { + u32 new_capacity = (u32)1 << (32 - leading_zeroes); + assert(new_capacity > new_len); + char32_t *new_str = buffer_realloc(buffer, line->str, new_capacity * sizeof *line->str); + if (!new_str) { + // allocation failed ): + return false; + } + // allocation successful + line->str = new_str; + } } - char32_t *new_str = buffer_realloc(buffer, line->str, new_capacity * sizeof *line->str); - if (!new_str) { - // allocation failed ): + } else if (line->len == 0) { + // start by allocating 8 code points + line->str = buffer_malloc(buffer, 8 * sizeof *line->str); + if (!line->str) { + // ): return false; } - // allocation successful - line->str = new_str; - line->capacity = new_capacity; } + line->len = new_len; return true; } @@ -579,8 +590,8 @@ static Status buffer_lines_set_min_capacity(TextBuffer *buffer, Line **lines, u3 } static void buffer_line_append_char(TextBuffer *buffer, Line *line, char32_t c) { - if (buffer_line_set_min_capacity(buffer, line, line->len + 1)) - line->str[line->len++] = c; + if (buffer_line_set_len(buffer, line, line->len + 1)) + line->str[line->len-1] = c; } static void buffer_line_free(Line *line) { @@ -695,7 +706,13 @@ void buffer_text_dimensions(TextBuffer *buffer, u32 *lines, u32 *columns) { *lines = buffer->nlines; } if (columns) { - *columns = buffer->longest_line_on_screen; + u32 longest_line = 0; + // which line on screen is the longest? + for (u32 l = buffer->first_line_on_screen; l <= buffer->last_line_on_screen && l < buffer->nlines; ++l) { + Line *line = &buffer->lines[l]; + longest_line = max_u32(longest_line, line->len); + } + *columns = longest_line; } } @@ -719,6 +736,7 @@ static void buffer_correct_scroll(TextBuffer *buffer) { u32 nlines, ncols; buffer_text_dimensions(buffer, &nlines, &ncols); double max_scroll_x = (double)ncols - buffer_display_cols(buffer); + max_scroll_x += 2; // allow "overscroll" (makes it so you can see the cursor when it's on the right side of the screen) double max_scroll_y = (double)nlines - buffer_display_lines(buffer); if (max_scroll_x <= 0) { buffer->scroll_x = 0; @@ -1225,10 +1243,9 @@ BufferPos buffer_insert_text_at_pos(TextBuffer *buffer, BufferPos pos, String32 Line *last_line = &buffer->lines[line_idx + n_added_lines]; u32 chars_moved = line->len - index; if (chars_moved) { - if (buffer_line_set_min_capacity(buffer, last_line, chars_moved)) { + if (buffer_line_set_len(buffer, last_line, chars_moved)) { memcpy(last_line->str, line->str + index, chars_moved * sizeof(char32_t)); line->len -= chars_moved; - last_line->len += chars_moved; } } } @@ -1240,15 +1257,13 @@ BufferPos buffer_insert_text_at_pos(TextBuffer *buffer, BufferPos pos, String32 u32 old_len = line->len; u32 new_len = old_len + text_line_len; if (new_len > old_len) { // handles both overflow and empty text lines - if (buffer_line_set_min_capacity(buffer, line, new_len)) { + if (buffer_line_set_len(buffer, line, new_len)) { // make space for text memmove(line->str + index + (new_len - old_len), line->str + index, (old_len - index) * sizeof(char32_t)); // insert text memcpy(line->str + index, str.str, text_line_len * sizeof(char32_t)); - - line->len = new_len; } str.str += text_line_len; @@ -1490,11 +1505,11 @@ void buffer_delete_chars_at_pos(TextBuffer *buffer, BufferPos pos, i64 nchars_) } buffer_shorten(buffer, line_idx + 1); } else { - // join last_line to line. + // join last_line[nchars:] to line. u32 last_line_chars_left = (u32)(last_line->len - nchars); - if (buffer_line_set_min_capacity(buffer, line, line->len + last_line_chars_left)) { - memcpy(line->str + line->len, last_line->str + nchars, last_line_chars_left * sizeof(char32_t)); - line->len += last_line_chars_left; + u32 old_len = line->len; + if (buffer_line_set_len(buffer, line, old_len + last_line_chars_left)) { + memcpy(line->str + old_len, last_line->str + nchars, last_line_chars_left * sizeof(char32_t)); } // remove all lines between line + 1 and last_line (inclusive). buffer_delete_lines(buffer, line_idx + 1, (u32)(last_line - line)); @@ -2139,8 +2154,6 @@ void buffer_render(TextBuffer *buffer, Rect r) { buffer->frame_earliest_line_modified = U32_MAX; buffer->frame_latest_line_modified = 0; - buffer->longest_line_on_screen = 0; - TextRenderState text_state = text_render_state_default; text_state.x = render_start_x; @@ -2151,9 +2164,10 @@ void buffer_render(TextBuffer *buffer, Rect r) { text_state.max_y = y2; if (!syntax_highlighting) rgba_u32_to_floats(colors[COLOR_TEXT], text_state.color); + + buffer->first_line_on_screen = start_line; for (u32 line_idx = start_line; line_idx < nlines; ++line_idx) { Line *line = &lines[line_idx]; - buffer->longest_line_on_screen = max_u32(buffer->longest_line_on_screen, line->len); if (arr_len(char_types) < line->len) { arr_set_len(char_types, line->len); } @@ -2187,6 +2201,7 @@ void buffer_render(TextBuffer *buffer, Rect r) { // next line text_state.x = render_start_x; if (text_state.y > text_state.max_y) { + buffer->last_line_on_screen = line_idx; // made it to the bottom of the buffer view. break; } |