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-rw-r--r--examples/dte/block-iter.c343
1 files changed, 0 insertions, 343 deletions
diff --git a/examples/dte/block-iter.c b/examples/dte/block-iter.c
deleted file mode 100644
index 73fc2ec..0000000
--- a/examples/dte/block-iter.c
+++ /dev/null
@@ -1,343 +0,0 @@
-#include <string.h>
-#include "block-iter.h"
-#include "util/debug.h"
-#include "util/utf8.h"
-#include "util/xmalloc.h"
-
-void block_iter_normalize(BlockIter *bi)
-{
- const Block *blk = bi->blk;
- if (bi->offset == blk->size && blk->node.next != bi->head) {
- bi->blk = BLOCK(blk->node.next);
- bi->offset = 0;
- }
-}
-
-/*
- * Move after next newline (beginning of next line or end of file).
- * Returns number of bytes iterator advanced.
- */
-size_t block_iter_eat_line(BlockIter *bi)
-{
- block_iter_normalize(bi);
- const size_t offset = bi->offset;
- if (unlikely(offset == bi->blk->size)) {
- return 0;
- }
-
- // There must be at least one newline
- if (bi->blk->nl == 1) {
- bi->offset = bi->blk->size;
- } else {
- const unsigned char *end;
- end = memchr(bi->blk->data + offset, '\n', bi->blk->size - offset);
- BUG_ON(!end);
- bi->offset = (size_t)(end + 1 - bi->blk->data);
- }
-
- return bi->offset - offset;
-}
-
-/*
- * Move to beginning of next line.
- * If there is no next line, iterator is not advanced.
- * Returns number of bytes iterator advanced.
- */
-size_t block_iter_next_line(BlockIter *bi)
-{
- block_iter_normalize(bi);
- const size_t offset = bi->offset;
- if (unlikely(offset == bi->blk->size)) {
- return 0;
- }
-
- // There must be at least one newline
- size_t new_offset;
- if (bi->blk->nl == 1) {
- new_offset = bi->blk->size;
- } else {
- const unsigned char *end;
- end = memchr(bi->blk->data + offset, '\n', bi->blk->size - offset);
- BUG_ON(!end);
- new_offset = (size_t)(end + 1 - bi->blk->data);
- }
- if (new_offset == bi->blk->size && bi->blk->node.next == bi->head) {
- return 0;
- }
-
- bi->offset = new_offset;
- return bi->offset - offset;
-}
-
-/*
- * Move to beginning of previous line.
- * Returns number of bytes moved, which is zero if there's no previous line.
- */
-size_t block_iter_prev_line(BlockIter *bi)
-{
- Block *blk = bi->blk;
- size_t offset = bi->offset;
- size_t start = offset;
-
- while (offset && blk->data[offset - 1] != '\n') {
- offset--;
- }
-
- if (!offset) {
- if (blk->node.prev == bi->head) {
- return 0;
- }
- bi->blk = blk = BLOCK(blk->node.prev);
- offset = blk->size;
- start += offset;
- }
-
- offset--;
- while (offset && blk->data[offset - 1] != '\n') {
- offset--;
- }
- bi->offset = offset;
- return start - offset;
-}
-
-size_t block_iter_get_char(const BlockIter *bi, CodePoint *up)
-{
- BlockIter tmp = *bi;
- return block_iter_next_char(&tmp, up);
-}
-
-size_t block_iter_next_char(BlockIter *bi, CodePoint *up)
-{
- size_t offset = bi->offset;
- if (unlikely(offset == bi->blk->size)) {
- if (unlikely(bi->blk->node.next == bi->head)) {
- return 0;
- }
- bi->blk = BLOCK(bi->blk->node.next);
- bi->offset = offset = 0;
- }
-
- // Note: this block can't be empty
- *up = bi->blk->data[offset];
- if (likely(*up < 0x80)) {
- bi->offset++;
- return 1;
- }
-
- *up = u_get_nonascii(bi->blk->data, bi->blk->size, &bi->offset);
- return bi->offset - offset;
-}
-
-size_t block_iter_prev_char(BlockIter *bi, CodePoint *up)
-{
- size_t offset = bi->offset;
- if (unlikely(offset == 0)) {
- if (unlikely(bi->blk->node.prev == bi->head)) {
- return 0;
- }
- bi->blk = BLOCK(bi->blk->node.prev);
- bi->offset = offset = bi->blk->size;
- }
-
- // Note: this block can't be empty
- *up = bi->blk->data[offset - 1];
- if (likely(*up < 0x80)) {
- bi->offset--;
- return 1;
- }
-
- *up = u_prev_char(bi->blk->data, &bi->offset);
- return offset - bi->offset;
-}
-
-size_t block_iter_next_column(BlockIter *bi)
-{
- CodePoint u;
- size_t size = block_iter_next_char(bi, &u);
- while (block_iter_get_char(bi, &u) && u_is_zero_width(u)) {
- size += block_iter_next_char(bi, &u);
- }
- return size;
-}
-
-size_t block_iter_prev_column(BlockIter *bi)
-{
- CodePoint u;
- size_t skip, total = 0;
- do {
- skip = block_iter_prev_char(bi, &u);
- total += skip;
- } while (skip && u_is_zero_width(u));
- return total;
-}
-
-size_t block_iter_bol(BlockIter *bi)
-{
- block_iter_normalize(bi);
- size_t offset = bi->offset;
- if (offset == 0 || offset == bi->blk->size) {
- return 0;
- }
-
- if (bi->blk->nl == 1) {
- offset = 0;
- } else {
- while (offset && bi->blk->data[offset - 1] != '\n') {
- offset--;
- }
- }
-
- const size_t ret = bi->offset - offset;
- bi->offset = offset;
- return ret;
-}
-
-size_t block_iter_eol(BlockIter *bi)
-{
- block_iter_normalize(bi);
- const Block *blk = bi->blk;
- const size_t offset = bi->offset;
- if (unlikely(offset == blk->size)) {
- // Cursor at end of last block
- return 0;
- }
- if (blk->nl == 1) {
- bi->offset = blk->size - 1;
- return bi->offset - offset;
- }
- const unsigned char *end = memchr(blk->data + offset, '\n', blk->size - offset);
- BUG_ON(!end);
- bi->offset = (size_t)(end - blk->data);
- return bi->offset - offset;
-}
-
-void block_iter_back_bytes(BlockIter *bi, size_t count)
-{
- while (count > bi->offset) {
- count -= bi->offset;
- bi->blk = BLOCK(bi->blk->node.prev);
- bi->offset = bi->blk->size;
- }
- bi->offset -= count;
-}
-
-void block_iter_skip_bytes(BlockIter *bi, size_t count)
-{
- size_t avail = bi->blk->size - bi->offset;
- while (count > avail) {
- count -= avail;
- bi->blk = BLOCK(bi->blk->node.next);
- bi->offset = 0;
- avail = bi->blk->size;
- }
- bi->offset += count;
-}
-
-void block_iter_goto_offset(BlockIter *bi, size_t offset)
-{
- Block *blk;
- block_for_each(blk, bi->head) {
- if (offset <= blk->size) {
- bi->blk = blk;
- bi->offset = offset;
- return;
- }
- offset -= blk->size;
- }
-}
-
-void block_iter_goto_line(BlockIter *bi, size_t line)
-{
- Block *blk = BLOCK(bi->head->next);
- size_t nl = 0;
- while (blk->node.next != bi->head && nl + blk->nl < line) {
- nl += blk->nl;
- blk = BLOCK(blk->node.next);
- }
-
- bi->blk = blk;
- bi->offset = 0;
- while (nl < line) {
- if (!block_iter_eat_line(bi)) {
- break;
- }
- nl++;
- }
-}
-
-size_t block_iter_get_offset(const BlockIter *bi)
-{
- const Block *blk;
- size_t offset = 0;
- block_for_each(blk, bi->head) {
- if (blk == bi->blk) {
- break;
- }
- offset += blk->size;
- }
- return offset + bi->offset;
-}
-
-char *block_iter_get_bytes(const BlockIter *bi, size_t len)
-{
- if (len == 0) {
- return NULL;
- }
-
- const Block *blk = bi->blk;
- size_t offset = bi->offset;
- size_t pos = 0;
- char *buf = xmalloc(len);
-
- while (pos < len) {
- const size_t avail = blk->size - offset;
- size_t count = MIN(len - pos, avail);
- memcpy(buf + pos, blk->data + offset, count);
- pos += count;
- BUG_ON(pos < len && blk->node.next == bi->head);
- blk = BLOCK(blk->node.next);
- offset = 0;
- }
-
- return buf;
-}
-
-// bi should be at bol
-void fill_line_nl_ref(BlockIter *bi, StringView *line)
-{
- block_iter_normalize(bi);
- line->data = bi->blk->data + bi->offset;
- const size_t max = bi->blk->size - bi->offset;
- if (unlikely(max == 0)) {
- // Cursor at end of last block
- line->length = 0;
- return;
- }
- if (bi->blk->nl == 1) {
- BUG_ON(line->data[max - 1] != '\n');
- line->length = max;
- return;
- }
- const unsigned char *nl = memchr(line->data, '\n', max);
- BUG_ON(!nl);
- line->length = (size_t)(nl - line->data + 1);
- BUG_ON(line->length == 0);
-}
-
-void fill_line_ref(BlockIter *bi, StringView *line)
-{
- fill_line_nl_ref(bi, line);
- // Trim the newline
- line->length -= (line->length > 0);
-}
-
-// Set the `line` argument to point to the current line and return
-// the offset of the cursor, relative to the start of the line
-// (zero means cursor is at bol)
-size_t fetch_this_line(const BlockIter *bi, StringView *line)
-{
- BlockIter tmp = *bi;
- size_t count = block_iter_bol(&tmp);
- fill_line_ref(&tmp, line);
- return count;
-}
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