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-rw-r--r--buffer.c152
1 files changed, 97 insertions, 55 deletions
diff --git a/buffer.c b/buffer.c
index 39a25a5..7ede69d 100644
--- a/buffer.c
+++ b/buffer.c
@@ -4,6 +4,7 @@
#include "util.c"
#include "text.h"
#include "string32.c"
+#include "arr.c"
// a position in the buffer
typedef struct {
@@ -19,16 +20,15 @@ typedef struct {
typedef enum {
BUFFER_EDIT_DELETE_TEXT, // text = deleted text, text_len = length of text deleted, pos = where text was deleted (first character)
- BUFFER_EDIT_INSERT_TEXT // text unused, text_len = length of text inserted, pos = where text was inserted (first character)
+ BUFFER_EDIT_INSERT_TEXT // text = NULL, text_len = length of text inserted, pos = where text was inserted (first character)
// (we don't need to know what text was inserted for BUFFER_EDIT_INSERT_TEXT, since it'll be right there)
} BufferEditType;
typedef struct BufferEdit {
- struct BufferEdit *next;
BufferEditType type;
BufferPos pos;
- u32 text_len;
- char32_t text[];
+ size_t text_len;
+ char32_t *text;
} BufferEdit;
typedef struct {
@@ -42,8 +42,8 @@ typedef struct {
u32 lines_capacity;
Line *lines;
char error[128];
- BufferEdit *undo_history;
- BufferEdit *redo_history;
+ BufferEdit *undo_history; // dynamic array of undo history
+ BufferEdit *redo_history; // dynamic array of redo history
} TextBuffer;
@@ -91,15 +91,15 @@ static void buffer_out_of_mem(TextBuffer *buffer) {
}
// add this edit to the undo history
-static void buffer_append_edit(TextBuffer *buffer, BufferEdit *edit) {
- edit->next = buffer->undo_history;
- buffer->undo_history = edit;
+static void buffer_append_edit(TextBuffer *buffer, BufferEdit const *edit) {
+ arr_add(buffer->undo_history, *edit);
+ if (!buffer->undo_history) buffer_out_of_mem(buffer);
}
// add this edit to the redo history
-static void buffer_append_redo(TextBuffer *buffer, BufferEdit *edit) {
- edit->next = buffer->redo_history;
- buffer->redo_history = edit;
+static void buffer_append_redo(TextBuffer *buffer, BufferEdit const *edit) {
+ arr_add(buffer->redo_history, *edit);
+ if (!buffer->redo_history) buffer_out_of_mem(buffer);
}
@@ -130,12 +130,12 @@ static bool buffer_pos_valid(TextBuffer *buffer, BufferPos p) {
// get some number of characters of text from the given position in the buffer.
-static Status buffer_get_text_at_pos(TextBuffer *buffer, BufferPos pos, char32_t *text, u32 nchars) {
+static Status buffer_get_text_at_pos(TextBuffer *buffer, BufferPos pos, char32_t *text, size_t nchars) {
if (!buffer_pos_valid(buffer, pos)) {
return false;
}
char32_t *p = text;
- u32 chars_left = nchars;
+ size_t chars_left = nchars;
Line *line = &buffer->lines[pos.line], *end = buffer->lines + buffer->nlines;
u32 index = pos.index;
while (chars_left) {
@@ -154,7 +154,7 @@ static Status buffer_get_text_at_pos(TextBuffer *buffer, BufferPos pos, char32_t
++line;
if (chars_left && line == end) {
// reached end of file before getting full text... this isn't good
- buffer_seterr(buffer, "Failed to fetch " U32_FMT " characters at " U32_FMT ":" U32_FMT ".", nchars, pos.line+1, pos.index+1);
+ buffer_seterr(buffer, "Failed to fetch %zu characters at " U32_FMT ":" U32_FMT ".", nchars, pos.line+1, pos.index+1);
return false;
}
}
@@ -163,32 +163,44 @@ static Status buffer_get_text_at_pos(TextBuffer *buffer, BufferPos pos, char32_t
// functions for creating buffer edits:
// call these before you make an edit to create an undo event
-static WarnUnusedResult BufferEdit *buffer_create_edit_delete_text(TextBuffer *buffer, BufferPos start, u32 len) {
- BufferEdit *e = buffer_calloc(buffer, 1, sizeof *e + len * sizeof *e->text);
- if (e) {
- e->type = BUFFER_EDIT_DELETE_TEXT;
- e->pos = start;
- e->text_len = len;
- if (!buffer_get_text_at_pos(buffer, start, e->text, len)) {
- free(e);
- e = NULL;
+static Status buffer_create_edit_delete_text(TextBuffer *buffer, BufferEdit *edit, BufferPos start, size_t len) {
+ edit->text = calloc(1, len * sizeof *edit->text);
+ if (edit->text) {
+ edit->type = BUFFER_EDIT_DELETE_TEXT;
+ edit->pos = start;
+ edit->text_len = len;
+ if (!buffer_get_text_at_pos(buffer, start, edit->text, len)) {
+ free(edit->text);
+ return false;
}
+ return true;
+ } else {
+ return false;
}
- return e;
}
-static WarnUnusedResult BufferEdit *buffer_create_edit_insert_text(TextBuffer *buffer, BufferPos start, u32 len) {
- if (!buffer_pos_valid(buffer, start)) return NULL;
- BufferEdit *e = buffer_calloc(buffer, 1, sizeof *e);
- if (e) {
- e->type = BUFFER_EDIT_INSERT_TEXT;
- e->pos = start;
- e->text_len = len;
- }
- return e;
+static Status buffer_create_edit_insert_text(TextBuffer *buffer, BufferEdit *edit, BufferPos start, size_t len) {
+ if (!buffer_pos_valid(buffer, start)) return false;
+ edit->type = BUFFER_EDIT_INSERT_TEXT;
+ edit->pos = start;
+ edit->text_len = len;
+ edit->text = NULL;
+ return true;
}
+static void buffer_edit_delete_text(TextBuffer *buffer, BufferPos start, size_t len) {
+ BufferEdit edit = {0};
+ if (buffer_create_edit_delete_text(buffer, &edit, start, len)) {
+ buffer_append_edit(buffer, &edit);
+ }
+}
+static void buffer_edit_insert_text(TextBuffer *buffer, BufferPos start, size_t len) {
+ BufferEdit edit = {0};
+ if (buffer_create_edit_insert_text(buffer, &edit, start, len)) {
+ buffer_append_edit(buffer, &edit);
+ }
+}
// grow capacity of line to at least minimum_capacity
// returns true if allocation was succesful
@@ -251,6 +263,9 @@ void buffer_free(TextBuffer *buffer) {
}
free(lines);
+ arr_free(buffer->undo_history);
+ arr_free(buffer->redo_history);
+
// zero buffer, except for error
char error[sizeof buffer->error];
memcpy(error, buffer->error, sizeof error);
@@ -913,6 +928,8 @@ static void buffer_insert_lines(TextBuffer *buffer, u32 where, u32 number) {
// inserts the given text, returning the position of the end of the text
BufferPos buffer_insert_text_at_pos(TextBuffer *buffer, BufferPos pos, String32 str) {
+ buffer_edit_insert_text(buffer, pos, str.len);
+
u32 line_idx = pos.line;
u32 index = pos.index;
Line *line = &buffer->lines[line_idx];
@@ -1012,6 +1029,11 @@ void buffer_delete_lines(TextBuffer *buffer, u32 first_line_idx, u32 nlines) {
}
void buffer_delete_chars_at_pos(TextBuffer *buffer, BufferPos pos, i64 nchars) {
+ assert(nchars >= 0);
+ if (nchars <= 0) return;
+
+ buffer_edit_delete_text(buffer, pos, (size_t)nchars);
+
u32 line_idx = pos.line;
u32 index = pos.index;
Line *line = &buffer->lines[line_idx], *lines_end = &buffer->lines[buffer->nlines];
@@ -1099,31 +1121,51 @@ void buffer_backspace_words_at_cursor(TextBuffer *buffer, i64 nwords) {
buffer_backspace_words_at_pos(buffer, &buffer->cursor_pos, nwords);
}
+// returns the inverse edit
+static Status buffer_undo_edit(TextBuffer *buffer, BufferEdit const *edit, BufferEdit *inverse) {
+ switch (edit->type) {
+ case BUFFER_EDIT_INSERT_TEXT:
+ // the inverse edit is the deletion of this text
+ if (!buffer_create_edit_delete_text(buffer, inverse, edit->pos, edit->text_len))
+ return false;
+ // delete the text
+ buffer_delete_chars_at_pos(buffer, edit->pos, (i64)edit->text_len);
+ break;
+ case BUFFER_EDIT_DELETE_TEXT: {
+ // the inverse edit is the insertion of this text
+ if (!buffer_create_edit_insert_text(buffer, inverse, edit->pos, edit->text_len))
+ return false;
+ // insert the text
+ String32 str = {edit->text_len, edit->text};
+ buffer_insert_text_at_pos(buffer, edit->pos, str);
+ } break;
+ }
+
+ return true;
+}
+
void buffer_undo(TextBuffer *buffer, i64 ntimes) {
for (i64 i = 0; i < ntimes; ++i) {
- BufferEdit *edit = buffer->undo_history;
- BufferEdit *inverse = NULL;
-
- switch (edit->type) {
- case BUFFER_EDIT_INSERT_TEXT:
- // the inverse edit is the deletion of this text
- inverse = buffer_create_edit_delete_text(buffer, edit->pos, edit->text_len);
- // delete the text
- buffer_delete_chars_at_pos(buffer, edit->pos, edit->text_len);
- break;
- case BUFFER_EDIT_DELETE_TEXT: {
- // the inverse edit is the insertion of this text
- inverse = buffer_create_edit_insert_text(buffer, edit->pos, edit->text_len);
- // insert the text
- String32 str = {edit->text_len, edit->text};
- buffer_insert_text_at_pos(buffer, edit->pos, str);
- } break;
+ BufferEdit *edit = arr_lastp(buffer->undo_history);
+ if (edit) {
+ BufferEdit inverse = {0};
+ if (buffer_undo_edit(buffer, edit, &inverse)) {
+ buffer_append_redo(buffer, &inverse);
+ arr_remove_last(buffer->undo_history);
+ }
}
+ }
+}
- if (inverse) {
- buffer_append_redo(buffer, inverse);
+void buffer_redo(TextBuffer *buffer, i64 ntimes) {
+ for (i64 i = 0; i < ntimes; ++i) {
+ BufferEdit *edit = arr_lastp(buffer->redo_history);
+ if (edit) {
+ BufferEdit inverse = {0};
+ if (buffer_undo_edit(buffer, edit, &inverse)) {
+ buffer_append_edit(buffer, &inverse);
+ arr_remove_last(buffer->redo_history);
+ }
}
-
- free(edit);
}
}