1 /* input_scrub.c - Break up input buffers into whole numbers of lines. 2 Copyright (C) 1987-2014 Free Software Foundation, Inc. 3 4 This file is part of GAS, the GNU Assembler. 5 6 GAS 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, or (at your option) 9 any later version. 10 11 GAS 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 GAS; see the file COPYING. If not, write to the Free 18 Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA 19 02110-1301, USA. */ 20 21 #include "as.h" 22 #include "filenames.h" 23 #include "input-file.h" 24 #include "sb.h" 25 #include "listing.h" 26 27 /* 28 * O/S independent module to supply buffers of sanitised source code 29 * to rest of assembler. We get sanitised input data of arbitrary length. 30 * We break these buffers on line boundaries, recombine pieces that 31 * were broken across buffers, and return a buffer of full lines to 32 * the caller. 33 * The last partial line begins the next buffer we build and return to caller. 34 * The buffer returned to caller is preceded by BEFORE_STRING and followed 35 * by AFTER_STRING, as sentinels. The last character before AFTER_STRING 36 * is a newline. 37 * Also looks after line numbers, for e.g. error messages. 38 */ 39 40 /* 41 * We don't care how filthy our buffers are, but our callers assume 42 * that the following sanitation has already been done. 43 * 44 * No comments, reduce a comment to a space. 45 * Reduce a tab to a space unless it is 1st char of line. 46 * All multiple tabs and spaces collapsed into 1 char. Tab only 47 * legal if 1st char of line. 48 * # line file statements converted to .line x;.file y; statements. 49 * Escaped newlines at end of line: remove them but add as many newlines 50 * to end of statement as you removed in the middle, to synch line numbers. 51 */ 52 53 #define BEFORE_STRING ("\n") 55 #define AFTER_STRING ("\0") /* memcpy of 0 chars might choke. */ 56 #define BEFORE_SIZE (1) 57 #define AFTER_SIZE (1) 58 59 #ifndef TC_EOL_IN_INSN 60 #define TC_EOL_IN_INSN(P) 0 61 #endif 62 63 static char *buffer_start; /*->1st char of full buffer area. */ 64 static char *partial_where; /*->after last full line in buffer. */ 65 static int partial_size; /* >=0. Number of chars in partial line in buffer. */ 66 67 /* Because we need AFTER_STRING just after last full line, it clobbers 68 1st part of partial line. So we preserve 1st part of partial line 69 here. */ 70 static char save_source[AFTER_SIZE]; 71 72 /* What is the largest size buffer that input_file_give_next_buffer() 73 could return to us? */ 74 static unsigned int buffer_length; 75 76 /* The index into an sb structure we are reading from. -1 if none. */ 77 static size_t sb_index = -1; 78 79 /* If we are reading from an sb structure, this is it. */ 80 static sb from_sb; 81 82 /* Should we do a conditional check on from_sb? */ 83 static int from_sb_is_expansion = 1; 84 85 /* The number of nested sb structures we have included. */ 86 int macro_nest; 87 88 /* We can have more than one source file open at once, though the info for all 89 but the latest one are saved off in a struct input_save. These files remain 90 open, so we are limited by the number of open files allowed by the 91 underlying OS. We may also sequentially read more than one source file in an 92 assembly. */ 93 94 /* We must track the physical file and line number for error messages. We also 95 track a "logical" file and line number corresponding to (C?) compiler 96 source line numbers. Whenever we open a file we must fill in 97 physical_input_file. So if it is NULL we have not opened any files yet. */ 98 99 static char *physical_input_file; 100 static char *logical_input_file; 101 102 /* 1-origin line number in a source file. */ 103 /* A line ends in '\n' or eof. */ 104 static unsigned int physical_input_line; 105 static int logical_input_line; 106 107 /* Struct used to save the state of the input handler during include files */ 108 struct input_save { 109 char * buffer_start; 110 char * partial_where; 111 int partial_size; 112 char save_source[AFTER_SIZE]; 113 size_t buffer_length; 114 char * physical_input_file; 115 char * logical_input_file; 116 unsigned int physical_input_line; 117 int logical_input_line; 118 size_t sb_index; 119 sb from_sb; 120 int from_sb_is_expansion; /* Should we do a conditional check? */ 121 struct input_save * next_saved_file; /* Chain of input_saves. */ 122 char * input_file_save; /* Saved state of input routines. */ 123 char * saved_position; /* Caller's saved position in buf. */ 124 }; 125 126 static struct input_save *input_scrub_push (char *saved_position); 127 static char *input_scrub_pop (struct input_save *arg); 128 129 /* Saved information about the file that .include'd this one. When we hit EOF, 130 we automatically pop to that file. */ 131 132 static struct input_save *next_saved_file; 133 134 /* Push the state of input reading and scrubbing so that we can #include. 135 The return value is a 'void *' (fudged for old compilers) to a save 136 area, which can be restored by passing it to input_scrub_pop(). */ 137 138 static struct input_save * 139 input_scrub_push (char *saved_position) 140 { 141 struct input_save *saved; 142 143 saved = (struct input_save *) xmalloc (sizeof *saved); 144 145 saved->saved_position = saved_position; 146 saved->buffer_start = buffer_start; 147 saved->partial_where = partial_where; 148 saved->partial_size = partial_size; 149 saved->buffer_length = buffer_length; 150 saved->physical_input_file = physical_input_file; 151 saved->logical_input_file = logical_input_file; 152 saved->physical_input_line = physical_input_line; 153 saved->logical_input_line = logical_input_line; 154 saved->sb_index = sb_index; 155 saved->from_sb = from_sb; 156 saved->from_sb_is_expansion = from_sb_is_expansion; 157 memcpy (saved->save_source, save_source, sizeof (save_source)); 158 saved->next_saved_file = next_saved_file; 159 saved->input_file_save = input_file_push (); 160 161 input_file_begin (); /* Reinitialize! */ 162 logical_input_line = -1; 163 logical_input_file = (char *) NULL; 164 buffer_length = input_file_buffer_size (); 165 sb_index = -1; 166 167 buffer_start = (char *) xmalloc ((BEFORE_SIZE + buffer_length 168 + buffer_length + AFTER_SIZE)); 169 memcpy (buffer_start, BEFORE_STRING, (int) BEFORE_SIZE); 170 171 return saved; 172 } 173 174 static char * 175 input_scrub_pop (struct input_save *saved) 176 { 177 char *saved_position; 178 179 input_scrub_end (); /* Finish off old buffer */ 180 181 input_file_pop (saved->input_file_save); 182 saved_position = saved->saved_position; 183 buffer_start = saved->buffer_start; 184 buffer_length = saved->buffer_length; 185 physical_input_file = saved->physical_input_file; 186 logical_input_file = saved->logical_input_file; 187 physical_input_line = saved->physical_input_line; 188 logical_input_line = saved->logical_input_line; 189 sb_index = saved->sb_index; 190 from_sb = saved->from_sb; 191 from_sb_is_expansion = saved->from_sb_is_expansion; 192 partial_where = saved->partial_where; 193 partial_size = saved->partial_size; 194 next_saved_file = saved->next_saved_file; 195 memcpy (save_source, saved->save_source, sizeof (save_source)); 196 197 free (saved); 198 return saved_position; 199 } 200 201 void 203 input_scrub_begin (void) 204 { 205 know (strlen (BEFORE_STRING) == BEFORE_SIZE); 206 know (strlen (AFTER_STRING) == AFTER_SIZE 207 || (AFTER_STRING[0] == '\0' && AFTER_SIZE == 1)); 208 209 input_file_begin (); 210 211 buffer_length = input_file_buffer_size (); 212 213 buffer_start = (char *) xmalloc ((BEFORE_SIZE + buffer_length 214 + buffer_length + AFTER_SIZE)); 215 memcpy (buffer_start, BEFORE_STRING, (int) BEFORE_SIZE); 216 217 /* Line number things. */ 218 logical_input_line = -1; 219 logical_input_file = (char *) NULL; 220 physical_input_file = NULL; /* No file read yet. */ 221 next_saved_file = NULL; /* At EOF, don't pop to any other file */ 222 do_scrub_begin (flag_m68k_mri); 223 } 224 225 void 226 input_scrub_end (void) 227 { 228 if (buffer_start) 229 { 230 free (buffer_start); 231 buffer_start = 0; 232 input_file_end (); 233 } 234 } 235 236 /* Start reading input from a new file. 237 Return start of caller's part of buffer. */ 238 239 char * 240 input_scrub_new_file (char *filename) 241 { 242 input_file_open (filename, !flag_no_comments); 243 physical_input_file = filename[0] ? filename : _("{standard input}"); 244 physical_input_line = 0; 245 246 partial_size = 0; 247 return (buffer_start + BEFORE_SIZE); 248 } 249 250 /* Include a file from the current file. Save our state, cause it to 251 be restored on EOF, and begin handling a new file. Same result as 252 input_scrub_new_file. */ 253 254 char * 255 input_scrub_include_file (char *filename, char *position) 256 { 257 next_saved_file = input_scrub_push (position); 258 return input_scrub_new_file (filename); 259 } 260 261 /* Start getting input from an sb structure. This is used when 262 expanding a macro. */ 263 264 void 265 input_scrub_include_sb (sb *from, char *position, int is_expansion) 266 { 267 int newline; 268 269 if (macro_nest > max_macro_nest) 270 as_fatal (_("macros nested too deeply")); 271 ++macro_nest; 272 273 #ifdef md_macro_start 274 if (is_expansion) 275 { 276 md_macro_start (); 277 } 278 #endif 279 280 next_saved_file = input_scrub_push (position); 281 282 /* Allocate sufficient space: from->len + optional newline. */ 283 newline = from->len >= 1 && from->ptr[0] != '\n'; 284 sb_build (&from_sb, from->len + newline); 285 from_sb_is_expansion = is_expansion; 286 if (newline) 287 { 288 /* Add the sentinel required by read.c. */ 289 sb_add_char (&from_sb, '\n'); 290 } 291 sb_scrub_and_add_sb (&from_sb, from); 292 293 /* Make sure the parser looks at defined contents when it scans for 294 e.g. end-of-line at the end of a macro. */ 295 sb_terminate (&from_sb); 296 297 sb_index = 1; 298 299 /* These variables are reset by input_scrub_push. Restore them 300 since we are, after all, still at the same point in the file. */ 301 logical_input_line = next_saved_file->logical_input_line; 302 logical_input_file = next_saved_file->logical_input_file; 303 } 304 305 void 306 input_scrub_close (void) 307 { 308 input_file_close (); 309 physical_input_line = 0; 310 logical_input_line = -1; 311 } 312 313 char * 314 input_scrub_next_buffer (char **bufp) 315 { 316 char *limit; /*->just after last char of buffer. */ 317 318 if (sb_index != (size_t) -1) 319 { 320 if (sb_index >= from_sb.len) 321 { 322 sb_kill (&from_sb); 323 if (from_sb_is_expansion) 324 { 325 cond_finish_check (macro_nest); 326 #ifdef md_macro_end 327 /* Allow the target to clean up per-macro expansion 328 data. */ 329 md_macro_end (); 330 #endif 331 } 332 --macro_nest; 333 partial_where = NULL; 334 if (next_saved_file != NULL) 335 *bufp = input_scrub_pop (next_saved_file); 336 return partial_where; 337 } 338 339 partial_where = from_sb.ptr + from_sb.len; 340 partial_size = 0; 341 *bufp = from_sb.ptr + sb_index; 342 sb_index = from_sb.len; 343 return partial_where; 344 } 345 346 *bufp = buffer_start + BEFORE_SIZE; 347 348 if (partial_size) 349 { 350 memmove (buffer_start + BEFORE_SIZE, partial_where, 351 (unsigned int) partial_size); 352 memcpy (buffer_start + BEFORE_SIZE, save_source, AFTER_SIZE); 353 } 354 limit = input_file_give_next_buffer (buffer_start 355 + BEFORE_SIZE 356 + partial_size); 357 if (limit) 358 { 359 char *p; /* Find last newline. */ 360 /* Terminate the buffer to avoid confusing TC_EOL_IN_INSN. */ 361 *limit = '\0'; 362 for (p = limit - 1; *p != '\n' || TC_EOL_IN_INSN (p); --p) 363 ; 364 ++p; 365 366 while (p <= buffer_start + BEFORE_SIZE) 367 { 368 int limoff; 369 370 limoff = limit - buffer_start; 371 buffer_length += input_file_buffer_size (); 372 buffer_start = (char *) xrealloc (buffer_start, 373 (BEFORE_SIZE 374 + 2 * buffer_length 375 + AFTER_SIZE)); 376 *bufp = buffer_start + BEFORE_SIZE; 377 limit = input_file_give_next_buffer (buffer_start + limoff); 378 379 if (limit == NULL) 380 { 381 as_warn (_("partial line at end of file ignored")); 382 partial_where = NULL; 383 if (next_saved_file) 384 *bufp = input_scrub_pop (next_saved_file); 385 return NULL; 386 } 387 388 /* Terminate the buffer to avoid confusing TC_EOL_IN_INSN. */ 389 *limit = '\0'; 390 for (p = limit - 1; *p != '\n' || TC_EOL_IN_INSN (p); --p) 391 ; 392 ++p; 393 } 394 395 partial_where = p; 396 partial_size = limit - p; 397 memcpy (save_source, partial_where, (int) AFTER_SIZE); 398 memcpy (partial_where, AFTER_STRING, (int) AFTER_SIZE); 399 } 400 else 401 { 402 partial_where = 0; 403 if (partial_size > 0) 404 { 405 as_warn (_("partial line at end of file ignored")); 406 } 407 408 /* Tell the listing we've finished the file. */ 409 LISTING_EOF (); 410 411 /* If we should pop to another file at EOF, do it. */ 412 if (next_saved_file) 413 { 414 *bufp = input_scrub_pop (next_saved_file); /* Pop state */ 415 /* partial_where is now correct to return, since we popped it. */ 416 } 417 } 418 return (partial_where); 419 } 420 421 /* The remaining part of this file deals with line numbers, error 423 messages and so on. Return TRUE if we opened any file. */ 424 425 int 426 seen_at_least_1_file (void) 427 { 428 return (physical_input_file != NULL); 429 } 430 431 void 432 bump_line_counters (void) 433 { 434 if (sb_index == (size_t) -1) 435 { 436 ++physical_input_line; 437 if (logical_input_line >= 0) 438 ++logical_input_line; 439 } 440 } 441 442 /* Tells us what the new logical line number and file are. 444 If the line_number is -1, we don't change the current logical line 445 number. If it is -2, we decrement the logical line number (this is 446 to support the .appfile pseudo-op inserted into the stream by 447 do_scrub_chars). 448 If the fname is NULL, we don't change the current logical file name. 449 Returns nonzero if the filename actually changes. */ 450 451 int 452 new_logical_line_flags (char *fname, /* DON'T destroy it! We point to it! */ 453 int line_number, 454 int flags) 455 { 456 switch (flags) 457 { 458 case 0: 459 break; 460 case 1: 461 if (line_number != -1) 462 abort (); 463 break; 464 case 1 << 1: 465 case 1 << 2: 466 /* FIXME: we could check that include nesting is correct. */ 467 break; 468 default: 469 abort (); 470 } 471 472 if (line_number >= 0) 473 logical_input_line = line_number; 474 else if (line_number == -1 && fname && !*fname && (flags & (1 << 2))) 475 { 476 logical_input_file = physical_input_file; 477 logical_input_line = physical_input_line; 478 fname = NULL; 479 } 480 481 if (fname 482 && (logical_input_file == NULL 483 || filename_cmp (logical_input_file, fname))) 484 { 485 logical_input_file = fname; 486 return 1; 487 } 488 else 489 return 0; 490 } 491 492 int 493 new_logical_line (char *fname, int line_number) 494 { 495 return new_logical_line_flags (fname, line_number, 0); 496 } 497 498 499 /* Return the current file name and line number. 501 namep should be char * const *, but there are compilers which screw 502 up declarations like that, and it's easier to avoid it. */ 503 504 void 505 as_where (char **namep, unsigned int *linep) 506 { 507 if (logical_input_file != NULL 508 && (linep == NULL || logical_input_line >= 0)) 509 { 510 *namep = logical_input_file; 511 if (linep != NULL) 512 *linep = logical_input_line; 513 } 514 else if (physical_input_file != NULL) 515 { 516 *namep = physical_input_file; 517 if (linep != NULL) 518 *linep = physical_input_line; 519 } 520 else 521 { 522 *namep = 0; 523 if (linep != NULL) 524 *linep = 0; 525 } 526 } 527
