diff options
| -rw-r--r-- | editor.c | 78 | ||||
| -rw-r--r-- | editor.h | 19 |
2 files changed, 68 insertions, 29 deletions
@@ -16,6 +16,9 @@ #define BUFFER_SIZE (1 << 20) +/* is c the start of a utf8 sequence? */ +#define isutf8(c) (((c)&0xC0)!=0x80) + /* Buffer holding the file content, either readonly mmap(2)-ed from the original * file or heap allocated to store the modifications. */ @@ -375,8 +378,14 @@ static void piece_init(Piece *p, Piece *prev, Piece *next, const char *data, siz p->len = len; } -/* returns the piece holding the text at byte offset pos. - * if pos is zero, then the begin sentinel piece is returned. */ +/* 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. + * + * in particular if pos is zero, the begin sentinel piece is returned. + */ static Location piece_get(Editor *ed, size_t pos) { Location loc = {}; size_t cur = 0; @@ -614,8 +623,8 @@ static void print_piece(Piece *p) { p->prev ? p->prev->index : -1, p->len, p->data); fflush(stderr); - write(1, p->data, p->len); - write(1, "\n", 1); + write(2, p->data, p->len); + write(2, "\n", 1); } void editor_debug(Editor *ed) { @@ -755,8 +764,9 @@ bool editor_modified(Editor *ed) { return ed->saved_action != ed->undo; } -static bool editor_iterator_init(Iterator *it, Piece *p, size_t off) { +static bool editor_iterator_init(Iterator *it, size_t pos, Piece *p, size_t off) { *it = (Iterator){ + .pos = pos, .piece = p, .start = p ? p->data : NULL, .end = p ? p->data + p->len : NULL, @@ -767,24 +777,34 @@ static bool editor_iterator_init(Iterator *it, Piece *p, size_t off) { Iterator editor_iterator_get(Editor *ed, size_t pos) { Iterator it; - Location loc = piece_get(ed, pos); - Piece *p = loc.piece; - editor_iterator_init(&it, p == &ed->begin ? p->next : p, loc.off); + 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; + } + + editor_iterator_init(&it, pos, p, off); return it; } -Iterator editor_iterator_byte_get(Editor *ed, size_t pos, char *b) { - Iterator it = editor_iterator_get(ed, pos); - editor_iterator_byte_peek(&it, b); - return it; +bool editor_iterator_byte_get(Iterator *it, char *b) { + if (editor_iterator_valid(it) && it->start <= it->text && it->text < it->end) { + *b = *it->text; + return true; + } + return false; } bool editor_iterator_next(Iterator *it) { - return editor_iterator_init(it, it->piece ? it->piece->next : NULL, 0); + return editor_iterator_init(it, it->pos, it->piece ? it->piece->next : NULL, 0); } bool editor_iterator_prev(Iterator *it) { - return editor_iterator_init(it, it->piece ? it->piece->prev : NULL, 0); + return editor_iterator_init(it, it->pos, it->piece ? it->piece->prev : NULL, 0); } bool editor_iterator_valid(const Iterator *it) { @@ -792,14 +812,6 @@ bool editor_iterator_valid(const Iterator *it) { return it->piece && it->piece->editor; } -bool editor_iterator_byte_peek(Iterator *it, char *b) { - if (editor_iterator_valid(it) && it->start <= it->text && it->text < it->end) { - *b = *it->text; - return true; - } - return false; -} - bool editor_iterator_byte_next(Iterator *it, char *b) { if (!editor_iterator_valid(it)) return false; @@ -809,6 +821,7 @@ bool editor_iterator_byte_next(Iterator *it, char *b) { return false; it->text = it->start; } + it->pos++; if (b) *b = *it->text; return true; @@ -823,11 +836,32 @@ bool editor_iterator_byte_prev(Iterator *it, char *b) { it->text = it->end; } --it->text; + --it->pos; if (b) *b = *it->text; return true; } +bool editor_iterator_char_next(Iterator *it, char *c) { + while (editor_iterator_byte_next(it, NULL)) { + if (isutf8(*it->text)) { + *c = *it->text; + return true; + } + } + return false; +} + +bool editor_iterator_char_prev(Iterator *it, char *c) { + while (editor_iterator_byte_prev(it, NULL)) { + if (isutf8(*it->text)) { + *c = *it->text; + return true; + } + } + return false; +} + size_t editor_bytes_get(Editor *ed, size_t pos, size_t len, char *buf) { if (!buf) return 0; @@ -4,10 +4,11 @@ typedef struct Editor Editor; typedef struct Piece Piece; typedef struct { - const char const *start; - const char const *end; - const char const *text; - const Piece const *piece; + const char const *start; /* begin of piece's data */ + const char const *end; /* pointer to the first byte after valid data i.e. [start, end) */ + const char const *text; /* current position within piece: start <= text < end */ + const Piece const *piece; /* internal state do not touch! */ + size_t pos; /* global position in bytes from start of file */ } Iterator; #define editor_iterate(ed, it, pos) \ @@ -26,14 +27,18 @@ bool editor_undo(Editor*); bool editor_redo(Editor*); size_t editor_bytes_get(Editor*, size_t pos, size_t len, char *buf); -bool editor_iterator_valid(const Iterator*); + Iterator editor_iterator_get(Editor*, size_t pos); +bool editor_iterator_valid(const Iterator*); bool editor_iterator_next(Iterator*); bool editor_iterator_prev(Iterator*); -Iterator editor_iterator_byte_get(Editor*, size_t pos, char *byte); + +bool editor_iterator_byte_get(Iterator *it, char *b); bool editor_iterator_byte_next(Iterator*, char *b); bool editor_iterator_byte_prev(Iterator*, char *b); -bool editor_iterator_byte_peek(Iterator *it, char *b); + +bool editor_iterator_char_next(Iterator *it, char *c); +bool editor_iterator_char_prev(Iterator *it, char *c); size_t editor_size(Editor*); bool editor_modified(Editor*); |