source3/utils/regedit_hexedit.c

   1 /*
   2  * Samba Unix/Linux SMB client library
   3  * Registry Editor
   4  * Copyright (C) Christopher Davis 2012
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 3 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include "includes.h"
  21 #include "regedit_hexedit.h"
  22
  23 /*
  24  offset    hex1         hex2         ascii
  25  00000000  FF FF FF FF  FF FF FF FF  ........
  26 */
  27
  28 #define HEX_COL1 10
  29 #define HEX_COL1_END 21
  30 #define HEX_COL2 23
  31 #define HEX_COL2_END 34
  32 #define ASCII_COL 36
  33 #define ASCII_COL_END LINE_WIDTH
  34 #define BYTES_PER_LINE 8
  35
  36 struct hexedit {
  37         size_t offset;
  38         size_t len;
  39         size_t alloc_size;
  40         int cursor_y;
  41         int cursor_x;
  42         size_t cursor_offset;
  43         size_t cursor_line_offset;
  44         int nibble;
  45         uint8_t *data;
  46         WINDOW *win;
  47 };
  48
  49 static int max_rows(WINDOW *win)
  50 {
  51         int maxy;
  52
  53         maxy = getmaxy(win);
  54
  55         return maxy - 1;
  56 }
  57
  58 struct hexedit *hexedit_new(TALLOC_CTX *ctx, WINDOW *parent, const void *data,
  59                             size_t sz)
  60 {
  61         WERROR rv;
  62         struct hexedit *buf;
  63
  64         buf = talloc_zero(ctx, struct hexedit);
  65         if (buf == NULL) {
  66                 return NULL;
  67         }
  68
  69         buf->win = parent;
  70
  71         rv = hexedit_set_buf(buf, data, sz);
  72         if (!W_ERROR_IS_OK(rv)) {
  73                 goto fail;
  74         }
  75
  76         return buf;
  77
  78 fail:
  79         talloc_free(buf);
  80
  81         return NULL;
  82 }
  83
  84 WERROR hexedit_set_buf(struct hexedit *buf, const void *data, size_t sz)
  85 {
  86         TALLOC_FREE(buf->data);
  87
  88         buf->data = talloc_zero_array(buf, uint8_t, sz);
  89         if (buf->data == NULL) {
  90                 return WERR_NOMEM;
  91         }
  92
  93         if (data != NULL) {
  94                 memcpy(buf->data, data, sz);
  95         }
  96
  97         buf->len = sz;
  98         buf->alloc_size = sz;
  99         buf->cursor_x = HEX_COL1;
 100         buf->cursor_y = 0;
 101         buf->cursor_offset = 0;
 102         buf->cursor_line_offset = 0;
 103         buf->nibble = 0;
 104
 105         return WERR_OK;
 106 }
 107
 108 const void *hexedit_get_buf(struct hexedit *buf)
 109 {
 110         return buf->data;
 111 }
 112
 113 size_t hexedit_get_buf_len(struct hexedit *buf)
 114 {
 115         return buf->len;
 116 }
 117
 118 static size_t bytes_per_screen(WINDOW *win)
 119 {
 120         return max_rows(win) * BYTES_PER_LINE;
 121 }
 122
 123 void hexedit_set_cursor(struct hexedit *buf)
 124 {
 125         wmove(buf->win, max_rows(buf->win), 0);
 126         wattron(buf->win, A_REVERSE | A_STANDOUT);
 127         wclrtoeol(buf->win);
 128         if (buf->cursor_offset < buf->len) {
 129                 wprintw(buf->win, "Len:%lu Off:%lu Val:0x%X", buf->len,
 130                         buf->cursor_offset, buf->data[buf->cursor_offset]);
 131         } else {
 132                 wprintw(buf->win, "Len:%lu Off:%lu", buf->len,
 133                         buf->cursor_offset);
 134         }
 135         wattroff(buf->win, A_REVERSE | A_STANDOUT);
 136         wmove(buf->win, buf->cursor_y, buf->cursor_x);
 137         wcursyncup(buf->win);
 138         wsyncup(buf->win);
 139         untouchwin(buf->win);
 140 }
 141
 142 void hexedit_refresh(struct hexedit *buf)
 143 {
 144         size_t end;
 145         size_t lineno;
 146         size_t off;
 147
 148         werase(buf->win);
 149         if (buf->len == 0) {
 150                 mvwprintw(buf->win, 0, 0, "%08X", 0);
 151                 return;
 152         }
 153
 154         end = buf->offset + bytes_per_screen(buf->win);
 155         if (end > buf->len) {
 156                 end = buf->len;
 157         }
 158
 159         for (off = buf->offset, lineno = 0;
 160              off < end;
 161              off += BYTES_PER_LINE, ++lineno) {
 162                 uint8_t *line = buf->data + off;
 163                 size_t i, endline;
 164
 165                 wmove(buf->win, lineno, 0);
 166                 wprintw(buf->win, "%08X  ", off);
 167
 168                 endline = BYTES_PER_LINE;
 169
 170                 if (off + BYTES_PER_LINE > buf->len) {
 171                         endline = buf->len - off;
 172                 }
 173
 174                 for (i = 0; i < endline; ++i) {
 175                         wprintw(buf->win, "%02X", line[i]);
 176                         if (i + 1 < endline) {
 177                                 if (i == 3) {
 178                                         wprintw(buf->win, "  ");
 179                                 } else {
 180                                         wprintw(buf->win, " ");
 181                                 }
 182                         }
 183                 }
 184
 185                 wmove(buf->win, lineno, ASCII_COL);
 186                 for (i = 0; i < endline; ++i) {
 187                         if (isprint(line[i])) {
 188                                 waddch(buf->win, line[i]);
 189                         } else {
 190                                 waddch(buf->win, '.');
 191                         }
 192                 }
 193         }
 194 }
 195
 196 static void calc_cursor_offset(struct hexedit *buf)
 197 {
 198         buf->cursor_offset = buf->offset + buf->cursor_y * BYTES_PER_LINE +
 199                                 buf->cursor_line_offset;
 200 }
 201
 202 static int offset_to_hex_col(size_t pos)
 203 {
 204         switch (pos) {
 205         case 0:
 206                 return HEX_COL1;
 207         case 1:
 208                 return HEX_COL1 + 3;
 209         case 2:
 210                 return HEX_COL1 + 6;
 211         case 3:
 212                 return HEX_COL1 + 9;
 213
 214         case 4:
 215                 return HEX_COL2;
 216         case 5:
 217                 return HEX_COL2 + 3;
 218         case 6:
 219                 return HEX_COL2 + 6;
 220         case 7:
 221                 return HEX_COL2 + 9;
 222         }
 223
 224         return -1;
 225 }
 226
 227 static bool scroll_up(struct hexedit *buf)
 228 {
 229         if (buf->offset == 0) {
 230                 return false;
 231         }
 232
 233         buf->offset -= BYTES_PER_LINE;
 234
 235         return true;
 236 }
 237
 238 static void cursor_down(struct hexedit *buf)
 239 {
 240         size_t space;
 241         bool need_refresh = false;
 242
 243         space = buf->offset + (buf->cursor_y + 1) * BYTES_PER_LINE;
 244         if (space > buf->len) {
 245                 return;
 246         }
 247
 248         if (buf->cursor_y + 1 == max_rows(buf->win)) {
 249                 buf->offset += BYTES_PER_LINE;
 250                 need_refresh = true;
 251         } else {
 252                 buf->cursor_y++;
 253         }
 254
 255         if (buf->cursor_offset + BYTES_PER_LINE > buf->len) {
 256                 buf->nibble = 0;
 257                 buf->cursor_offset = buf->len;
 258                 buf->cursor_line_offset = buf->len - space;
 259                 if (buf->cursor_x >= ASCII_COL) {
 260                         buf->cursor_x = ASCII_COL + buf->cursor_line_offset;
 261                 } else {
 262                         buf->cursor_x = offset_to_hex_col(buf->cursor_line_offset);
 263                 }
 264         }
 265         if (need_refresh) {
 266                 hexedit_refresh(buf);
 267         }
 268         calc_cursor_offset(buf);
 269 }
 270
 271 static void cursor_up(struct hexedit *buf)
 272 {
 273         if (buf->cursor_y == 0) {
 274                 if (scroll_up(buf)) {
 275                         hexedit_refresh(buf);
 276                 }
 277         } else {
 278                 buf->cursor_y--;
 279         }
 280
 281         calc_cursor_offset(buf);
 282 }
 283
 284 static bool is_over_gap(struct hexedit *buf)
 285 {
 286         int col;
 287
 288         if (buf->cursor_x < ASCII_COL) {
 289                 if (buf->cursor_x >= HEX_COL2) {
 290                         col = buf->cursor_x - HEX_COL2;
 291                 } else {
 292                         col = buf->cursor_x - HEX_COL1;
 293                 }
 294
 295                 switch (col) {
 296                 case 2:
 297                 case 5:
 298                 case 8:
 299                         return true;
 300                 }
 301         }
 302
 303         return false;
 304 }
 305
 306 static void cursor_left(struct hexedit *buf)
 307 {
 308         if (buf->cursor_x == HEX_COL1) {
 309                 return;
 310         }
 311         if (buf->cursor_x == HEX_COL2) {
 312                 buf->cursor_x = HEX_COL1_END - 1;
 313                 buf->cursor_line_offset = 3;
 314                 buf->nibble = 1;
 315         } else if (buf->cursor_x == ASCII_COL) {
 316                 size_t off = buf->offset + buf->cursor_y * BYTES_PER_LINE;
 317                 if (off + 7 >= buf->len) {
 318                         size_t lastpos = buf->len - off;
 319                         buf->cursor_x = offset_to_hex_col(lastpos) + 1;
 320                         buf->cursor_line_offset = lastpos;
 321                 } else {
 322                         buf->cursor_x = HEX_COL2_END - 1;
 323                         buf->cursor_line_offset = 7;
 324                 }
 325                 buf->nibble = 1;
 326         } else {
 327                 if (buf->cursor_x > ASCII_COL || buf->nibble == 0) {
 328                         buf->cursor_line_offset--;
 329                 }
 330                 buf->cursor_x--;
 331                 buf->nibble = !buf->nibble;
 332         }
 333
 334         if (is_over_gap(buf)) {
 335                 buf->cursor_x--;
 336         }
 337
 338         calc_cursor_offset(buf);
 339 }
 340
 341 static void cursor_right(struct hexedit *buf)
 342 {
 343         int new_x = buf->cursor_x + 1;
 344
 345         if (new_x == ASCII_COL_END) {
 346                 return;
 347         }
 348         if ((buf->cursor_x >= ASCII_COL || buf->nibble == 1) &&
 349             buf->cursor_offset == buf->len) {
 350                 if (buf->cursor_x < ASCII_COL) {
 351                         new_x = ASCII_COL;
 352                         buf->cursor_line_offset = 0;
 353                         buf->nibble = 0;
 354                 } else {
 355                         return;
 356                 }
 357         }
 358         if (new_x == HEX_COL1_END) {
 359                 new_x = HEX_COL2;
 360                 buf->cursor_line_offset = 4;
 361                 buf->nibble = 0;
 362         } else if (new_x == HEX_COL2_END) {
 363                 new_x = ASCII_COL;
 364                 buf->cursor_line_offset = 0;
 365                 buf->nibble = 0;
 366         } else {
 367                 if (buf->cursor_x >= ASCII_COL || buf->nibble == 1) {
 368                         buf->cursor_line_offset++;
 369                 }
 370                 buf->nibble = !buf->nibble;
 371         }
 372
 373         buf->cursor_x = new_x;
 374
 375         if (is_over_gap(buf)) {
 376                 buf->cursor_x++;
 377         }
 378
 379         calc_cursor_offset(buf);
 380 }
 381
 382 static void do_edit(struct hexedit *buf, int c)
 383 {
 384         uint8_t *byte;
 385
 386         if (buf->cursor_offset == buf->len) {
 387                 hexedit_resize_buffer(buf, buf->len + 1);
 388         }
 389
 390         byte = buf->data + buf->cursor_offset;
 391
 392         if (buf->cursor_x >= ASCII_COL) {
 393                 *byte = (uint8_t)c;
 394
 395                 mvwprintw(buf->win, buf->cursor_y,
 396                           offset_to_hex_col(buf->cursor_line_offset), "%X", c);
 397                 if (!isprint(c)) {
 398                         c = '.';
 399                 }
 400                 mvwaddch(buf->win, buf->cursor_y,
 401                          ASCII_COL + buf->cursor_line_offset, c);
 402                 if (buf->cursor_x + 1 != ASCII_COL_END) {
 403                         cursor_right(buf);
 404                 } else {
 405                         cursor_down(buf);
 406                 }
 407         } else {
 408                 if (!isxdigit(c)) {
 409                         return;
 410                 }
 411                 c = toupper(c);
 412                 waddch(buf->win, c);
 413
 414                 if (isdigit(c)) {
 415                         c = c - '0';
 416                 } else {
 417                         c = c - 'A' + 10;
 418                 }
 419                 if (buf->nibble == 0) {
 420                         *byte = (*byte & 0x0f) | c << 4;
 421                 } else {
 422                         *byte = (*byte & 0xf0) | c;
 423                 }
 424
 425                 c = *byte;
 426                 if (!isprint(c)) {
 427                         c = '.';
 428                 }
 429                 mvwaddch(buf->win, buf->cursor_y,
 430                          ASCII_COL + buf->cursor_line_offset, c);
 431
 432                 if (buf->cursor_x + 1 != HEX_COL2_END) {
 433                         cursor_right(buf);
 434                 } else {
 435                         cursor_down(buf);
 436                 }
 437         }
 438
 439         hexedit_refresh(buf);
 440 }
 441
 442 static void erase_at(struct hexedit *buf, size_t pos)
 443 {
 444         if (pos >= buf->len) {
 445                 return;
 446         }
 447
 448         if (pos < buf->len - 1) {
 449                 /* squeeze the character out of the buffer */
 450                 uint8_t *p = buf->data + pos;
 451                 uint8_t *end = buf->data + buf->len;
 452                 memmove(p, p + 1, end - p - 1);
 453         }
 454
 455         buf->len--;
 456         hexedit_refresh(buf);
 457 }
 458
 459 static void do_backspace(struct hexedit *buf)
 460 {
 461         size_t off;
 462         bool do_erase = true;
 463
 464         if (buf->cursor_offset == 0) {
 465                 return;
 466         }
 467
 468         off = buf->cursor_offset;
 469         if (buf->cursor_x == ASCII_COL) {
 470                 cursor_up(buf);
 471                 buf->cursor_line_offset = 7;
 472                 buf->cursor_x = ASCII_COL_END - 1;
 473                 calc_cursor_offset(buf);
 474         } else if (buf->cursor_x == HEX_COL1) {
 475                 cursor_up(buf);
 476                 buf->cursor_line_offset = 7;
 477                 buf->cursor_x = HEX_COL2_END - 1;
 478                 buf->nibble = 1;
 479                 calc_cursor_offset(buf);
 480         } else {
 481                 if (buf->cursor_x < ASCII_COL && buf->nibble) {
 482                         do_erase = false;
 483                 }
 484                 cursor_left(buf);
 485         }
 486         if (do_erase) {
 487                 erase_at(buf, off - 1);
 488         }
 489 }
 490
 491 static void do_delete(struct hexedit *buf)
 492 {
 493         erase_at(buf, buf->cursor_offset);
 494 }
 495
 496 void hexedit_driver(struct hexedit *buf, int c)
 497 {
 498         switch (c) {
 499         case HE_CURSOR_UP:
 500                 cursor_up(buf);
 501                 break;
 502         case HE_CURSOR_DOWN:
 503                 cursor_down(buf);
 504                 break;
 505         case HE_CURSOR_LEFT:
 506                 cursor_left(buf);
 507                 break;
 508         case HE_CURSOR_RIGHT:
 509                 cursor_right(buf);
 510                 break;
 511         case HE_CURSOR_PGUP:
 512                 break;
 513         case HE_CURSOR_PGDN:
 514                 break;
 515         case HE_BACKSPACE:
 516                 do_backspace(buf);
 517                 break;
 518         case HE_DELETE:
 519                 do_delete(buf);
 520                 break;
 521         default:
 522                 do_edit(buf, c & 0xff);
 523                 break;
 524         }
 525
 526         hexedit_set_cursor(buf);
 527 }
 528
 529 WERROR hexedit_resize_buffer(struct hexedit *buf, size_t newsz)
 530 {
 531         /* reset the cursor if it'll be out of bounds
 532            after the resize */
 533         if (buf->cursor_offset > newsz) {
 534                 buf->cursor_y = 0;
 535                 buf->cursor_x = HEX_COL1;
 536                 buf->offset = 0;
 537                 buf->cursor_offset = 0;
 538                 buf->cursor_line_offset = 0;
 539                 buf->nibble = 0;
 540         }
 541
 542         if (newsz > buf->len) {
 543                 if (newsz > buf->alloc_size) {
 544                         uint8_t *d;
 545                         buf->alloc_size *= 2;
 546                         if (newsz > buf->alloc_size) {
 547                                 buf->alloc_size = newsz;
 548                         }
 549                         d = talloc_realloc(buf, buf->data, uint8_t,
 550                                            buf->alloc_size);
 551                         if (d == NULL) {
 552                                 return WERR_NOMEM;
 553                         }
 554                         buf->data = d;
 555                 }
 556                 memset(buf->data + buf->len, '\0', newsz - buf->len);
 557                 buf->len = newsz;
 558         } else {
 559                 buf->len = newsz;
 560         }
 561
 562         return WERR_OK;
 563 }