regedit: Import hex editor.

This was tested separately editing files. It needs to be
connected to regedit's value editor.

Reviewed-by: Andreas Schneider <asn@samba.org>
Reviewed-by: Michael Adam <obnox@samba.org>

2 files changed, 456 insertions, 0 deletions

diff --git a/source3/utils/regedit_hexedit.c b/source3/utils/regedit_hexedit.c
new file mode 100644
index 0000000000..69ed622c7e
--- /dev/null
+++ b/source3/utils/regedit_hexedit.c
@@ -0,0 +1,406 @@
+#include "includes.h"
+#include "regedit_hexedit.h"
+
+static int max_rows(WINDOW *win)
+{
+	int maxy, maxx;
+
+	getmaxyx(win, maxy, maxx);
+
+	return maxy - 1;
+}
+
+static int hexedit_free(struct hexedit *buf)
+{
+	if (buf->status_line) {
+		delwin(buf->status_line);
+	}
+	if (buf->win) {
+		delwin(buf->win);
+	}
+
+	return 0;
+}
+
+struct hexedit *hexedit_new(TALLOC_CTX *ctx, WINDOW *parent, int nlines,
+			    int y, int x, size_t sz)
+{
+	struct hexedit *buf;
+
+	buf = talloc_zero(ctx, struct hexedit);
+	if (buf == NULL) {
+		return NULL;
+	}
+
+	talloc_set_destructor(buf, hexedit_free);
+
+	buf->data = talloc_zero_array(buf, uint8_t, sz);
+	if (buf->data == NULL) {
+		goto fail;
+	}
+
+	buf->len = sz;
+	buf->alloc_size = sz;
+	buf->win = derwin(parent, nlines, LINE_WIDTH, y, x);
+	if (buf->win == NULL) {
+		goto fail;
+	}
+	buf->cursor_x = HEX_COL1;
+
+	buf->status_line = derwin(buf->win, 1, LINE_WIDTH, max_rows(buf->win), 0);
+	if (buf->status_line == NULL) {
+		goto fail;
+	}
+	wattron(buf->status_line, A_REVERSE | A_STANDOUT);
+
+	return buf;
+
+fail:
+	talloc_free(buf);
+
+	return NULL;
+}
+
+static size_t bytes_per_screen(WINDOW *win)
+{
+	return max_rows(win) * BYTES_PER_LINE;
+}
+
+void hexedit_set_cursor(struct hexedit *buf)
+{
+	werase(buf->status_line);
+	wprintw(buf->status_line, "Len:%lu Off:%lu Val:0x%X", buf->len,
+		buf->cursor_offset, buf->data[buf->cursor_offset]);
+	wrefresh(buf->status_line);
+	wmove(buf->win, buf->cursor_y, buf->cursor_x);
+}
+
+void hexedit_refresh(struct hexedit *buf)
+{
+	size_t end;
+	size_t lineno;
+	size_t off;
+
+	werase(buf->win);
+
+	end = buf->offset + bytes_per_screen(buf->win);
+	if (end > buf->len) {
+		end = buf->len;
+	}
+
+	for (off = buf->offset, lineno = 0; off < end; off += BYTES_PER_LINE, ++lineno) {
+		uint8_t *line = buf->data + off;
+		size_t i, endline;
+
+		wmove(buf->win, lineno, 0);
+		wprintw(buf->win, "%08X  ", off);
+
+		endline = BYTES_PER_LINE;
+
+		if (off + BYTES_PER_LINE > buf->len) {
+			endline = buf->len - off;
+		}
+
+		for (i = 0; i < endline; ++i) {
+			wprintw(buf->win, "%02X", line[i]);
+			if (i + 1 < endline) {
+				if (i == 3) {
+					wprintw(buf->win, "  ");
+				} else {
+					wprintw(buf->win, " ");
+				}
+			}
+		}
+
+		wmove(buf->win, lineno, ASCII_COL);
+		for (i = 0; i < endline; ++i) {
+			if (isprint(line[i])) {
+				waddch(buf->win, line[i]);
+			} else {
+				waddch(buf->win, '.');
+			}
+		}
+	}
+}
+
+static void calc_cursor_offset(struct hexedit *buf)
+{
+	buf->cursor_offset = buf->offset + buf->cursor_y * BYTES_PER_LINE + buf->cursor_line_offset;
+}
+
+static int offset_to_hex_col(size_t pos)
+{
+	switch (pos) {
+	case 0:
+		return HEX_COL1;
+	case 1:
+		return HEX_COL1 + 3;
+	case 2:
+		return HEX_COL1 + 6;
+	case 3:
+		return HEX_COL1 + 9;
+
+	case 4:
+		return HEX_COL2;
+	case 5:
+		return HEX_COL2 + 3;
+	case 6:
+		return HEX_COL2 + 6;
+	case 7:
+		return HEX_COL2 + 9;
+	}
+
+	return -1;
+}
+
+static bool scroll_down(struct hexedit *buf)
+{
+	if (buf->offset + bytes_per_screen(buf->win) >= buf->len) {
+		return false;
+	}
+
+	buf->offset += BYTES_PER_LINE;
+
+	return true;
+}
+
+static bool scroll_up(struct hexedit *buf)
+{
+	if (buf->offset == 0) {
+		return false;
+	}
+
+	buf->offset -= BYTES_PER_LINE;
+
+	return true;
+}
+
+static void cursor_down(struct hexedit *buf)
+{
+	if (buf->cursor_y + 1 == max_rows(buf->win)) {
+		if (scroll_down(buf)) {
+			hexedit_refresh(buf);
+		}
+	} else {
+		if (buf->cursor_offset + BYTES_PER_LINE >= buf->len) {
+			return;
+		}
+		buf->cursor_y++;
+	}
+
+	calc_cursor_offset(buf);
+}
+
+static void cursor_up(struct hexedit *buf)
+{
+	if (buf->cursor_y == 0) {
+		if (scroll_up(buf)) {
+			hexedit_refresh(buf);
+		}
+	} else {
+		buf->cursor_y--;
+	}
+
+	calc_cursor_offset(buf);
+}
+
+static bool is_over_gap(struct hexedit *buf)
+{
+	int col;
+
+	if (buf->cursor_x < ASCII_COL) {
+		if (buf->cursor_x >= HEX_COL2) {
+			col = buf->cursor_x - HEX_COL2;
+		} else {
+			col = buf->cursor_x - HEX_COL1;
+		}
+
+		switch (col) {
+		case 2:
+		case 5:
+		case 8:
+			return true;
+		}
+	}
+
+	return false;
+}
+
+static void cursor_left(struct hexedit *buf)
+{
+	if (buf->cursor_x == HEX_COL1) {
+		return;
+	}
+	if (buf->cursor_x == HEX_COL2) {
+		buf->cursor_x = HEX_COL1_END - 1;
+		buf->cursor_line_offset = 3;
+		buf->nibble = 1;
+	} else if (buf->cursor_x == ASCII_COL) {
+		size_t off = buf->offset + buf->cursor_y * BYTES_PER_LINE;
+		if (off + 7 >= buf->len) {
+			size_t lastpos = buf->len - off - 1;
+			buf->cursor_x = offset_to_hex_col(lastpos) + 1;
+			buf->cursor_line_offset = lastpos;
+		} else {
+			buf->cursor_x = HEX_COL2_END - 1;
+			buf->cursor_line_offset = 7;
+		}
+		buf->nibble = 1;
+	} else {
+		if (buf->cursor_x > ASCII_COL || buf->nibble == 0) {
+			buf->cursor_line_offset--;
+		}
+		buf->cursor_x--;
+		buf->nibble = !buf->nibble;
+	}
+
+	if (is_over_gap(buf)) {
+		buf->cursor_x--;
+	}
+
+	calc_cursor_offset(buf);
+}
+
+static void cursor_right(struct hexedit *buf)
+{
+	int new_x = buf->cursor_x + 1;
+
+	if (new_x == ASCII_COL_END) {
+		return;
+	}
+	if ((buf->cursor_x >= ASCII_COL || buf->nibble == 1) &&
+	    buf->cursor_offset + 1 == buf->len) {
+		if (buf->cursor_x < ASCII_COL) {
+			new_x = ASCII_COL;
+			buf->cursor_line_offset = 0;
+			buf->nibble = 0;
+		} else {
+			return;
+		}
+	}
+	if (new_x == HEX_COL1_END) {
+		new_x = HEX_COL2;
+		buf->cursor_line_offset = 4;
+		buf->nibble = 0;
+	} else if (new_x == HEX_COL2_END) {
+		new_x = ASCII_COL;
+		buf->cursor_line_offset = 0;
+		buf->nibble = 0;
+	} else {
+		if (buf->cursor_x >= ASCII_COL || buf->nibble == 1) {
+			buf->cursor_line_offset++;
+		}
+		buf->nibble = !buf->nibble;
+	}
+
+	buf->cursor_x = new_x;
+
+	if (is_over_gap(buf)) {
+		buf->cursor_x++;
+	}
+
+	calc_cursor_offset(buf);
+}
+
+static void do_edit(struct hexedit *buf, int c)
+{
+	uint8_t *byte;
+
+	byte = buf->data + buf->cursor_offset;
+
+	if (buf->cursor_x >= ASCII_COL) {
+		*byte = (uint8_t)c;
+
+		mvwprintw(buf->win, buf->cursor_y,
+			  offset_to_hex_col(buf->cursor_line_offset), "%X", c);
+		if (!isprint(c)) {
+			c = '.';
+		}
+		mvwaddch(buf->win, buf->cursor_y, ASCII_COL + buf->cursor_line_offset, c);
+		cursor_right(buf);
+	} else {
+		if (!isxdigit(c)) {
+			return;
+		}
+		c = toupper(c);
+		waddch(buf->win, c);
+
+		if (isdigit(c)) {
+			c = c - '0';
+		} else {
+			c = c - 'A' + 10;
+		}
+		if (buf->nibble == 0) {
+			*byte = (*byte & 0x0f) | c << 4;
+		} else {
+			*byte = (*byte & 0xf0) | c;
+		}
+
+		c = *byte;
+		if (!isprint(c)) {
+			c = '.';
+		}
+		mvwaddch(buf->win, buf->cursor_y, ASCII_COL + buf->cursor_line_offset, c);
+
+		if (buf->cursor_x + 1 != HEX_COL2_END) {
+			cursor_right(buf);
+		}
+	}
+}
+
+void hexedit_driver(struct hexedit *buf, int c)
+{
+	switch (c) {
+	case HE_CURSOR_UP:
+		cursor_up(buf);
+		break;
+	case HE_CURSOR_DOWN:
+		cursor_down(buf);
+		break;
+	case HE_CURSOR_LEFT:
+		cursor_left(buf);
+		break;
+	case HE_CURSOR_RIGHT:
+		cursor_right(buf);
+		break;
+	case HE_CURSOR_PGUP:
+		break;
+	case HE_CURSOR_PGDN:
+		break;
+	default:
+		do_edit(buf, c & 0xff);
+		break;
+	}
+}
+
+WERROR hexedit_resize_buffer(struct hexedit *buf, size_t newsz)
+{
+	/* reset the cursor if it'll be out of bounds
+	   after the resize */
+	if (buf->cursor_offset >= newsz) {
+		buf->cursor_y = 0;
+		buf->cursor_x = HEX_COL1;
+		buf->offset = 0;
+		buf->cursor_offset = 0;
+		buf->cursor_line_offset = 0;
+		buf->nibble = 0;
+	}
+
+	if (newsz > buf->len) {
+		if (newsz > buf->alloc_size) {
+			uint8_t *d;
+			d = talloc_realloc(buf, buf->data, uint8_t, newsz);
+			if (d == NULL) {
+				return WERR_NOMEM;
+			}
+			buf->data = d;
+			buf->alloc_size = newsz;
+		}
+		memset(buf->data + buf->len, '\0', newsz - buf->len);
+		buf->len = newsz;
+	} else {
+		buf->len = newsz;
+	}
+
+	return WERR_OK;
+}
diff --git a/source3/utils/regedit_hexedit.h b/source3/utils/regedit_hexedit.h
new file mode 100644
index 0000000000..1a2db912be
--- /dev/null
+++ b/source3/utils/regedit_hexedit.h
@@ -0,0 +1,50 @@
+#ifndef _HEXEDIT_H_
+#define _HEXEDIT_H_
+
+#include <ncurses.h>
+
+enum {
+	HE_CURSOR_UP = 0x1000,
+	HE_CURSOR_DOWN = 0x1100,
+	HE_CURSOR_LEFT = 0x1200,
+	HE_CURSOR_RIGHT = 0x1300,
+	HE_CURSOR_PGUP = 0x1400,
+	HE_CURSOR_PGDN = 0x1500
+};
+
+/*
+ offset    hex1         hex2         ascii
+ 00000000  FF FF FF FF  FF FF FF FF  ........
+*/
+
+#define LINE_WIDTH 44
+#define HEX_COL1 10
+#define HEX_COL1_END 21
+#define HEX_COL2 23
+#define HEX_COL2_END 34
+#define ASCII_COL 36
+#define ASCII_COL_END LINE_WIDTH
+#define BYTES_PER_LINE 8
+
+struct hexedit {
+	size_t offset;
+	size_t len;
+	size_t alloc_size;
+	int cursor_y;
+	int cursor_x;
+	size_t cursor_offset;
+	size_t cursor_line_offset;
+	int nibble;
+	uint8_t *data;
+	WINDOW *win;
+	WINDOW *status_line;
+};
+
+struct hexedit *hexedit_new(TALLOC_CTX *ctx, WINDOW *parent, int nlines,
+			    int y, int x, size_t sz);
+void hexedit_set_cursor(struct hexedit *buf);
+void hexedit_refresh(struct hexedit *buf);
+void hexedit_driver(struct hexedit *buf, int c);
+WERROR hexedit_resize_buffer(struct hexedit *buf, size_t newsz);
+
+#endif