From 6f84b07d939be6ef5e50c5468b95651fb4465500 Mon Sep 17 00:00:00 2001 From: Nicholas Noll Date: Fri, 12 Jun 2020 17:53:56 -0700 Subject: prototype of tinycurses --- sys/libterm/buffer.c | 326 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 326 insertions(+) create mode 100644 sys/libterm/buffer.c (limited to 'sys/libterm/buffer.c') diff --git a/sys/libterm/buffer.c b/sys/libterm/buffer.c new file mode 100644 index 0000000..b903e71 --- /dev/null +++ b/sys/libterm/buffer.c @@ -0,0 +1,326 @@ +#include "term.h" + +/* row operations */ +void +zero(Row *row, int start, int len) +{ + int i; + Cell cell = { + .r = L'\0', + .pen = {0}, + }; + + for (i = start; i < len + start; i++) + row->cells[i] = cell; + row->dirty = true; +} + +void +roll(Row *start, Row *end, int count) +{ + int n = end - start; + + count %= n; + if (count < 0) + count += n; + + if (count) { + char buf[count * sizeof(Row)]; + memcpy(buf, start, count * sizeof(Row)); + memmove(start, start + count, (n - count) * sizeof(Row)); + memcpy(end - count, buf, count * sizeof(Row)); + for (Row *row = start; row < end; row++) + row->dirty = true; + } +} + +/* buffer operations */ +void +bclear(Buffer *b) +{ + int i; + Cell cell = { + .r = L'\0', + .pen = { + .state = PenNormal, + .col.fg = -1, + .col.bg = -1, + }, + }; + + for (i = 0; i < b->nrow; i++) { + Row *row = b->row + i; + for (int j = 0; j < b->ncol; j++) { + row->cells[j] = cell; + row->dirty = true; + } + } +} + +void +bfree(Buffer *b) +{ + int i; + + for (i = 0; i < b->nrow; i++) + free(b->row[i].cells); + + free(b->row); + + for (i = 0; i < b->scroll.size; i++) + free(b->scroll.buf[i].cells); + + free(b->scroll.buf); + free(b->tabs); +} + +void +bscroll(Buffer *b, int s) +{ + /* work in screenfuls */ + int ssz = b->scroll.bot - b->scroll.top; + + if (s > ssz) { + bscroll(b, ssz); + bscroll(b, s - ssz); + return; + } + if (s < -ssz) { + bscroll(b, -ssz); + bscroll(b, s + ssz); + return; + } + + b->scroll.above += s; + if (b->scroll.above >= b->scroll.size) + b->scroll.above = b->scroll.size; + + if (s > 0 && b->scroll.size) { + for (int i = 0; i < s; i++) { + Row tmp = b->scroll.top[i]; + b->scroll.top[i] = b->scroll.buf[b->scroll.index]; + b->scroll.buf[b->scroll.index] = tmp; + + b->scroll.index++; + if (b->scroll.index == b->scroll.size) + b->scroll.index = 0; + } + } + roll(b->scroll.top, b->scroll.bot, s); + if (s < 0 && b->scroll.size) { + for (int i = (-s) - 1; i >= 0; i--) { + b->scroll.index--; + if (b->scroll.index == -1) + b->scroll.index = b->scroll.size - 1; + + Row tmp = b->scroll.top[i]; + b->scroll.top[i] = b->scroll.buf[b->scroll.index]; + b->scroll.buf[b->scroll.index] = tmp; + b->scroll.top[i].dirty = true; + } + } +} + +void +bresize(Buffer *b, int nrow, int ncol) +{ + Row *row = b->row; + + if (b->nrow != nrow) { + if (b->crow >= row + nrow) { + /* scroll up instead of simply chopping off bottom */ + bscroll(b, (b->crow - b->row) - nrow + 1); + } + while (b->nrow > nrow) { + free(row[b->nrow - 1].cells); + b->nrow--; + } + + row = realloc(row, sizeof(Row) * nrow); + } + + if (b->maxcols < ncol) { + for (int r = 0; r < b->nrow; r++) { + row[r].cells = realloc(row[r].cells, sizeof(Cell) * ncol); + if (b->ncol < ncol) + zero(row + r, b->ncol, ncol - b->ncol); + row[r].dirty = true; + } + Row *sbuf = b->scroll.buf; + for (int r = 0; r < b->scroll.size; r++) { + sbuf[r].cells = realloc(sbuf[r].cells, sizeof(Cell) * ncol); + if (b->ncol < ncol) + zero(sbuf + r, b->ncol, ncol - b->ncol); + } + b->tabs = realloc(b->tabs, sizeof(*b->tabs) * ncol); + for (int c = b->ncol; c < ncol; c++) + b->tabs[c] = !(c & 7); + b->maxcols = ncol; + b->ncol = ncol; + } else if (b->ncol != ncol) { + for (int r = 0; r < b->nrow; r++) + row[r].dirty = true; + b->ncol = ncol; + } + + int deltarows = 0; + if (b->nrow < nrow) { + while (b->nrow < nrow) { + row[b->nrow].cells = calloc(b->maxcols, sizeof(Cell)); + zero(row + b->nrow, 0, b->maxcols); + b->nrow++; + } + + /* prepare for backfill */ + if (b->crow >= b->scroll.bot - 1) { + deltarows = b->row + nrow - b->crow - 1; + if (deltarows > b->scroll.above) + deltarows = b->scroll.above; + } + } + + b->crow += row - b->row; + b->scroll.top = row; + b->scroll.bot = row + nrow; + b->row = row; + + /* perform backfill */ + if (deltarows > 0) { + bscroll(b, -deltarows); + b->crow += deltarows; + } +} + +bool +binit(Buffer *b, int rows, int cols, int size) +{ + b->pen.state = PenNormal; + b->pen.col.fg = b->pen.col.fg = -1; + + if (size < 0) + size = 0; + if (size && !(b->scroll.buf = calloc(size, sizeof(Row)))) + return false; + + b->scroll.size = size; + bresize(b, rows, cols); + return true; +} + +void +bboundary(Buffer *b, Row **bs, Row **be, Row **as, Row **ae) +{ + if (bs) + *bs = nil; + if (be) + *be = nil; + if (as) + *as = nil; + if (ae) + *ae = nil; + if (!b->scroll.size) + return; + + if (b->scroll.above) { + if (bs) + *bs = &b->scroll.buf[(b->scroll.index - b->scroll.above + b->scroll.size) % b->scroll.size]; + if (be) + *be = &b->scroll.buf[(b->scroll.index-1 + b->scroll.size) % b->scroll.size]; + } + if (b->scroll.below) { + if (as) + *as = &b->scroll.buf[b->scroll.index]; + if (ae) + *ae = &b->scroll.buf[(b->scroll.index + b->scroll.below-1) % b->scroll.size]; + } +} + +Row * +browfirst(Buffer *b) +{ + Row *bstart; + if (!b->scroll.size || !b->scroll.above) + return b->row; + bboundary(b, &bstart, nil, nil, nil); + return bstart; +} + +Row * +browlast(Buffer *b) +{ + Row *aend; + if (!b->scroll.size || !b->scroll.below) + return b->row + b->nrow - 1; + bboundary(b, nil, nil, nil, &aend); + return aend; +} + +Row * +brownext(Buffer *b, Row *row) +{ + Row *before_start, *before_end, *after_start, *after_end; + Row *first = b->row, *last = b->row + b->nrow - 1; + + if (!row) + return nil; + + bboundary(b, &before_start, &before_end, &after_start, &after_end); + + if (row >= first && row < last) + return ++row; + if (row == last) + return after_start; + if (row == before_end) + return first; + if (row == after_end) + return nil; + if (row == &b->scroll.buf[b->scroll.size - 1]) + return b->scroll.buf; + return ++row; +} + +Row * +bprevrow(Buffer *b, Row *row) +{ + Row *before_start, *before_end, *after_start, *after_end; + Row *first = b->row, *last = b->row + b->nrow - 1; + + if (!row) + return nil; + + bboundary(b, &before_start, &before_end, &after_start, &after_end); + + if (row > first && row <= last) + return --row; + if (row == first) + return before_end; + if (row == before_start) + return nil; + if (row == after_start) + return last; + if (row == b->scroll.buf) + return &b->scroll.buf[b->scroll.size - 1]; + return --row; +} + +void +brender(Buffer *b, Term *t) +{ + int r, c, n; + char u[UTFmax+1]; + Row *row; + Cell *cell; + + for (r = 0; r < b->nrow; r++) { + row = b->row + r; + if (!row->dirty) + continue; + + for (c = 0; c < b->ncol; c++) { + cell = row->cells + c; + tsetpen(t, cell->pen); + n = utf8·runetobyte(u, &cell->r); + twrite(t, n, u); + } + } +} -- cgit v1.2.1