From 6c2963f91b90f73da862ac9feac25cdcc1266869 Mon Sep 17 00:00:00 2001 From: Leo Tenenbaum Date: Tue, 15 Dec 2020 14:03:49 -0500 Subject: text insertion working very well! --- buffer.c | 119 ++++++++++++++++++++++++++++++++++++++++++++++++--------------- 1 file changed, 92 insertions(+), 27 deletions(-) (limited to 'buffer.c') diff --git a/buffer.c b/buffer.c index 42c5ee3..47fd1ba 100644 --- a/buffer.c +++ b/buffer.c @@ -2,6 +2,7 @@ #include "unicode.h" #include "util.c" #include "text.h" +#include "string32.c" // a position in the buffer typedef struct { @@ -11,6 +12,7 @@ typedef struct { typedef struct { u32 len; + u32 capacity; char32_t *str; } Line; @@ -19,6 +21,7 @@ typedef struct { Font *font; BufferPos cursor_pos; u8 tab_width; + bool out_of_mem; // set to true if an allocation fails float x1, y1, x2, y2; u32 nlines; Line *lines; @@ -30,19 +33,49 @@ void buffer_create(TextBuffer *buffer, Font *font) { buffer->tab_width = 4; } -static Status buffer_line_append_char(Line *line, char32_t c) { - if (line->len == 0 || util_is_power_of_2(line->len)) { - // when the length of a line gets to a power of 2, double its allocated size - size_t new_size = line->len == 0 ? 1 : line->len * 2; - line->str = realloc(line->str, new_size * sizeof *line->str); - if (!line->str) { +// grow capacity of line to at least minimum_capacity +// returns true if allocation was succesful +static Status buffer_line_grow(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) { + // overflow. this could only happen with an extremely long line, so we + // treat it as + buffer->out_of_mem = true; return false; } + char32_t *new_str = realloc(line->str, new_capacity * sizeof *line->str); + if (!new_str) { + // allocation failed ): + buffer->out_of_mem = true; + return false; + } + // allocation successful + line->str = new_str; + line->capacity = new_capacity; } - line->str[line->len++] = c; return true; } +static void buffer_line_append_char(TextBuffer *buffer, Line *line, char32_t c) { + if (buffer_line_grow(buffer, line, line->len + 1)) + line->str[line->len++] = c; +} + +// Does not free the pointer `buffer` (buffer might not have even been allocated with malloc) +void buffer_free(TextBuffer *buffer) { + Line *lines = buffer->lines; + u32 nlines = buffer->nlines; + for (u32 i = 0; i < nlines; ++i) { + free(lines[i].str); + } + free(lines); + buffer->nlines = 0; + buffer->lines = NULL; +} + + // fp should be a binary file Status buffer_load_file(TextBuffer *buffer, FILE *fp) { assert(fp); @@ -97,10 +130,7 @@ Status buffer_load_file(TextBuffer *buffer, FILE *fp) { u32 line_idx = buffer->nlines - 1; Line *line = &buffer->lines[line_idx]; - if (!buffer_line_append_char(line, c)) { - success = false; - break; - } + buffer_line_append_char(buffer, line, c); } } } @@ -108,10 +138,7 @@ Status buffer_load_file(TextBuffer *buffer, FILE *fp) { } if (ferror(fp)) success = false; if (!success) { - for (u32 i = 0; i < buffer->nlines; ++i) - free(buffer->lines[i].str); - free(buffer->lines); - buffer->nlines = 0; + buffer_free(buffer); } return success; @@ -134,18 +161,6 @@ static void buffer_print(TextBuffer const *buffer) { fflush(stdout); } -// Does not free the pointer `buffer` (buffer might not have even been allocated with malloc) -void buffer_free(TextBuffer *buffer) { - Line *lines = buffer->lines; - u32 nlines = buffer->nlines; - for (u32 i = 0; i < nlines; ++i) { - free(lines[i].str); - } - free(lines); - buffer->nlines = 0; - buffer->lines = NULL; -} - static u32 buffer_index_to_column(TextBuffer *buffer, u32 line, u32 index) { char32_t *str = buffer->lines[line].str; u32 col = 0; @@ -469,6 +484,56 @@ static void buffer_scroll_to_cursor(TextBuffer *buffer) { buffer_correct_scroll(buffer); // it's possible that min/max_scroll_x/y go too far } +void buffer_insert_text_at_cursor(TextBuffer *buffer, char32_t const *text, size_t len) { + u32 cur_line_idx = buffer->cursor_pos.line; + u32 cur_index = buffer->cursor_pos.index; + char32_t const *end = text + len; + + // `text` could consist of multiple lines, e.g. U"line 1\nline 2", + // so we need to go through them one by one + while (text != end) { + char32_t const *end_of_line = util_mem32chr_const(text, U'\n', len); + if (!end_of_line) end_of_line = end; + + u32 text_line_len = (u32)(end_of_line - text); + Line *cur_line = &buffer->lines[cur_line_idx]; + u32 old_len = cur_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_grow(buffer, cur_line, new_len)) { + // make space for text + memmove(cur_line->str + cur_index + (new_len - old_len), + cur_line->str + cur_index, + (old_len - cur_index) * sizeof *text); + // insert text + memcpy(cur_line->str + cur_index, text, text_line_len * sizeof *text); + + cur_line->len = new_len; + } + + text += text_line_len; + len -= text_line_len; + cur_index = buffer->cursor_pos.index += text_line_len; + } + + // @TODO: deal with multiple lines + } + + buffer_scroll_to_cursor(buffer); +} + +void buffer_insert_char_at_cursor(TextBuffer *buffer, char32_t c) { + buffer_insert_text_at_cursor(buffer, &c, 1); +} + +void buffer_insert_utf8_at_cursor(TextBuffer *buffer, char const *utf8) { + String32 s32 = s32_from_utf8(utf8); + if (s32.str) { + buffer_insert_text_at_cursor(buffer, s32.str, s32.len); + s32_free(&s32); + } +} + bool buffer_cursor_move_left(TextBuffer *buffer) { if (buffer_pos_move_left(buffer, &buffer->cursor_pos)) { buffer_scroll_to_cursor(buffer); -- cgit v1.2.3