diff options
| -rw-r--r-- | text.c | 49 |
1 files changed, 29 insertions, 20 deletions
@@ -129,7 +129,8 @@ static bool cache_delete(Text *ed, Piece *p, size_t off, size_t len); static Piece *piece_alloc(Text *ed); static void piece_free(Piece *p); static void piece_init(Piece *p, Piece *prev, Piece *next, const char *data, size_t len); -static Location piece_get(Text *ed, size_t pos); +static Location piece_get_intern(Text *ed, size_t pos); +static Location piece_get_extern(Text *ed, size_t pos); /* span management */ static void span_init(Span *span, Piece *start, Piece *end); static void span_swap(Text *ed, Span *old, Span *new); @@ -396,21 +397,38 @@ static void piece_init(Piece *p, Piece *prev, Piece *next, const char *data, siz } /* returns the piece holding the text at byte offset pos. if pos happens to - * be at a piece boundry, the piece to the left is returned with an offset - * of piece->len this is convenient for modifications to the piece chain - * where both pieces (the returned one and the one following it) are needed, - * but unsuitable as a public interface. + * be at a piece boundry i.e. the first byte of a piece then the previous piece + * to the left is returned with an offset of piece->len. this is convenient for + * modifications to the piece chain where both pieces (the returned one and the + * one following it) are needed, but unsuitable as a public interface. * * in particular if pos is zero, the begin sentinel piece is returned. */ -static Location piece_get(Text *ed, size_t pos) { +static Location piece_get_intern(Text *ed, size_t pos) { Location loc = {}; size_t cur = 0; for (Piece *p = &ed->begin; p->next; p = p->next) { if (cur <= pos && pos <= cur + p->len) { loc.piece = p; loc.off = pos - cur; - return loc; + break; + } + cur += p->len; + } + + return loc; +} + +/* similiar to piece_get_intern but usable as a public API. returns the piece + * holding the text at byte offset pos. never returns a sentinel piece. */ +static Location piece_get_extern(Text *ed, size_t pos) { + Location loc = {}; + size_t cur = 0; + for (Piece *p = ed->begin.next; p->next; p = p->next) { + if (cur <= pos && pos < cur + p->len) { + loc.piece = p; + loc.off = pos - cur; + break; } cur += p->len; } @@ -480,7 +498,7 @@ bool text_insert_raw(Text *ed, size_t pos, const char *data, size_t len) { ed->marks[mark] += len; } - Location loc = piece_get(ed, pos); + Location loc = piece_get_intern(ed, pos); Piece *p = loc.piece; size_t off = loc.off; if (cache_insert(ed, p, off, data, len)) @@ -691,7 +709,7 @@ bool text_delete(Text *ed, size_t pos, size_t len) { } } - Location loc = piece_get(ed, pos); + Location loc = piece_get_intern(ed, pos); Piece *p = loc.piece; size_t off = loc.off; if (cache_delete(ed, p, off, len)) @@ -807,17 +825,8 @@ static bool text_iterator_init(Iterator *it, size_t pos, Piece *p, size_t off) { Iterator text_iterator_get(Text *ed, size_t pos) { Iterator it; - Piece *p; - size_t cur = 0, off = 0; - for (p = ed->begin.next; p->next; p = p->next) { - if (cur <= pos && pos < cur + p->len) { - off = pos - cur; - break; - } - cur += p->len; - } - - text_iterator_init(&it, pos, p, off); + Location loc = piece_get_extern(ed, pos); + text_iterator_init(&it, pos, loc.piece, loc.off); return it; } |