1 /* input_scrub.c - Break up input buffers into whole numbers of lines. 2 Copyright 1987, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 3 2000, 2001, 2003 4 Free Software Foundation, Inc. 5 6 This file is part of GAS, the GNU Assembler. 7 8 GAS is free software; you can redistribute it and/or modify 9 it under the terms of the GNU General Public License as published by 10 the Free Software Foundation; either version 2, or (at your option) 11 any later version. 12 13 GAS is distributed in the hope that it will be useful, 14 but WITHOUT ANY WARRANTY; without even the implied warranty of 15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 GNU General Public License for more details. 17 18 You should have received a copy of the GNU General Public License 19 along with GAS; see the file COPYING. If not, write to the Free 20 Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA 21 02110-1301, USA. */ 22 23 #include <errno.h> /* Need this to make errno declaration right */ 24 #include "as.h" 25 #include "input-file.h" 26 #include "sb.h" 27 #include "listing.h" 28 29 /* 30 * O/S independent module to supply buffers of sanitised source code 31 * to rest of assembler. We get sanitised input data of arbitrary length. 32 * We break these buffers on line boundaries, recombine pieces that 33 * were broken across buffers, and return a buffer of full lines to 34 * the caller. 35 * The last partial line begins the next buffer we build and return to caller. 36 * The buffer returned to caller is preceded by BEFORE_STRING and followed 37 * by AFTER_STRING, as sentinels. The last character before AFTER_STRING 38 * is a newline. 39 * Also looks after line numbers, for e.g. error messages. 40 */ 41 42 /* 43 * We don't care how filthy our buffers are, but our callers assume 44 * that the following sanitation has already been done. 45 * 46 * No comments, reduce a comment to a space. 47 * Reduce a tab to a space unless it is 1st char of line. 48 * All multiple tabs and spaces collapsed into 1 char. Tab only 49 * legal if 1st char of line. 50 * # line file statements converted to .line x;.file y; statements. 51 * Escaped newlines at end of line: remove them but add as many newlines 52 * to end of statement as you removed in the middle, to synch line numbers. 53 */ 54 55 #define BEFORE_STRING ("\n") 56 #define AFTER_STRING ("\0") /* memcpy of 0 chars might choke. */ 57 #define BEFORE_SIZE (1) 58 #define AFTER_SIZE (1) 59 60 static char *buffer_start; /*->1st char of full buffer area. */ 61 static char *partial_where; /*->after last full line in buffer. */ 62 static int partial_size; /* >=0. Number of chars in partial line in buffer. */ 63 64 /* Because we need AFTER_STRING just after last full line, it clobbers 65 1st part of partial line. So we preserve 1st part of partial line 66 here. */ 67 static char save_source[AFTER_SIZE]; 68 69 /* What is the largest size buffer that input_file_give_next_buffer() 70 could return to us? */ 71 static unsigned int buffer_length; 72 73 /* The index into an sb structure we are reading from. -1 if none. */ 74 static int sb_index = -1; 75 76 /* If we are reading from an sb structure, this is it. */ 77 static sb from_sb; 78 79 /* Should we do a conditional check on from_sb? */ 80 static int from_sb_is_expansion = 1; 81 82 /* The number of nested sb structures we have included. */ 83 int macro_nest; 84 85 /* We can have more than one source file open at once, though the info for all 86 but the latest one are saved off in a struct input_save. These files remain 87 open, so we are limited by the number of open files allowed by the 88 underlying OS. We may also sequentially read more than one source file in an 89 assembly. */ 90 91 /* We must track the physical file and line number for error messages. We also 92 track a "logical" file and line number corresponding to (C?) compiler 93 source line numbers. Whenever we open a file we must fill in 94 physical_input_file. So if it is NULL we have not opened any files yet. */ 95 96 static char *physical_input_file; 97 static char *logical_input_file; 98 99 typedef unsigned int line_numberT; /* 1-origin line number in a source file. */ 100 /* A line ends in '\n' or eof. */ 101 102 static line_numberT physical_input_line; 103 static int logical_input_line; 104 105 /* Struct used to save the state of the input handler during include files */ 106 struct input_save { 107 char * buffer_start; 108 char * partial_where; 109 int partial_size; 110 char save_source[AFTER_SIZE]; 111 unsigned int buffer_length; 112 char * physical_input_file; 113 char * logical_input_file; 114 line_numberT physical_input_line; 115 int logical_input_line; 116 int sb_index; 117 sb from_sb; 118 int from_sb_is_expansion; /* Should we do a conditional check? */ 119 struct input_save * next_saved_file; /* Chain of input_saves. */ 120 char * input_file_save; /* Saved state of input routines. */ 121 char * saved_position; /* Caller's saved position in buf. */ 122 }; 123 124 static struct input_save *input_scrub_push (char *saved_position); 125 static char *input_scrub_pop (struct input_save *arg); 126 127 /* Saved information about the file that .include'd this one. When we hit EOF, 128 we automatically pop to that file. */ 129 130 static struct input_save *next_saved_file; 131 132 /* Push the state of input reading and scrubbing so that we can #include. 133 The return value is a 'void *' (fudged for old compilers) to a save 134 area, which can be restored by passing it to input_scrub_pop(). */ 135 136 static struct input_save * 137 input_scrub_push (char *saved_position) 138 { 139 register struct input_save *saved; 140 141 saved = (struct input_save *) xmalloc (sizeof *saved); 142 143 saved->saved_position = saved_position; 144 saved->buffer_start = buffer_start; 145 saved->partial_where = partial_where; 146 saved->partial_size = partial_size; 147 saved->buffer_length = buffer_length; 148 saved->physical_input_file = physical_input_file; 149 saved->logical_input_file = logical_input_file; 150 saved->physical_input_line = physical_input_line; 151 saved->logical_input_line = logical_input_line; 152 saved->sb_index = sb_index; 153 saved->from_sb = from_sb; 154 saved->from_sb_is_expansion = from_sb_is_expansion; 155 memcpy (saved->save_source, save_source, sizeof (save_source)); 156 saved->next_saved_file = next_saved_file; 157 saved->input_file_save = input_file_push (); 158 159 input_file_begin (); /* Reinitialize! */ 160 logical_input_line = -1; 161 logical_input_file = (char *) NULL; 162 buffer_length = input_file_buffer_size (); 163 sb_index = -1; 164 165 buffer_start = xmalloc ((BEFORE_SIZE + buffer_length + buffer_length + AFTER_SIZE)); 166 memcpy (buffer_start, BEFORE_STRING, (int) BEFORE_SIZE); 167 168 return saved; 169 } 170 171 static char * 172 input_scrub_pop (struct input_save *saved) 173 { 174 char *saved_position; 175 176 input_scrub_end (); /* Finish off old buffer */ 177 178 input_file_pop (saved->input_file_save); 179 saved_position = saved->saved_position; 180 buffer_start = saved->buffer_start; 181 buffer_length = saved->buffer_length; 182 physical_input_file = saved->physical_input_file; 183 logical_input_file = saved->logical_input_file; 184 physical_input_line = saved->physical_input_line; 185 logical_input_line = saved->logical_input_line; 186 sb_index = saved->sb_index; 187 from_sb = saved->from_sb; 188 from_sb_is_expansion = saved->from_sb_is_expansion; 189 partial_where = saved->partial_where; 190 partial_size = saved->partial_size; 191 next_saved_file = saved->next_saved_file; 192 memcpy (save_source, saved->save_source, sizeof (save_source)); 193 194 free (saved); 195 return saved_position; 196 } 197 198 void 199 input_scrub_begin (void) 200 { 201 know (strlen (BEFORE_STRING) == BEFORE_SIZE); 202 know (strlen (AFTER_STRING) == AFTER_SIZE 203 || (AFTER_STRING[0] == '\0' && AFTER_SIZE == 1)); 204 205 input_file_begin (); 206 207 buffer_length = input_file_buffer_size (); 208 209 buffer_start = xmalloc ((BEFORE_SIZE + buffer_length + buffer_length + AFTER_SIZE)); 210 memcpy (buffer_start, BEFORE_STRING, (int) BEFORE_SIZE); 211 212 /* Line number things. */ 213 logical_input_line = -1; 214 logical_input_file = (char *) NULL; 215 physical_input_file = NULL; /* No file read yet. */ 216 next_saved_file = NULL; /* At EOF, don't pop to any other file */ 217 do_scrub_begin (flag_m68k_mri); 218 } 219 220 void 221 input_scrub_end (void) 222 { 223 if (buffer_start) 224 { 225 free (buffer_start); 226 buffer_start = 0; 227 input_file_end (); 228 } 229 } 230 231 /* Start reading input from a new file. 232 Return start of caller's part of buffer. */ 233 234 char * 235 input_scrub_new_file (char *filename) 236 { 237 input_file_open (filename, !flag_no_comments); 238 physical_input_file = filename[0] ? filename : _("{standard input}"); 239 physical_input_line = 0; 240 241 partial_size = 0; 242 return (buffer_start + BEFORE_SIZE); 243 } 244 245 /* Include a file from the current file. Save our state, cause it to 246 be restored on EOF, and begin handling a new file. Same result as 247 input_scrub_new_file. */ 248 249 char * 250 input_scrub_include_file (char *filename, char *position) 251 { 252 next_saved_file = input_scrub_push (position); 253 return input_scrub_new_file (filename); 254 } 255 256 /* Start getting input from an sb structure. This is used when 257 expanding a macro. */ 258 259 void 260 input_scrub_include_sb (sb *from, char *position, int is_expansion) 261 { 262 if (macro_nest > max_macro_nest) 263 as_fatal (_("macros nested too deeply")); 264 ++macro_nest; 265 266 #ifdef md_macro_start 267 if (is_expansion) 268 { 269 md_macro_start (); 270 } 271 #endif 272 273 next_saved_file = input_scrub_push (position); 274 275 sb_new (&from_sb); 276 from_sb_is_expansion = is_expansion; 277 if (from->len >= 1 && from->ptr[0] != '\n') 278 { 279 /* Add the sentinel required by read.c. */ 280 sb_add_char (&from_sb, '\n'); 281 } 282 sb_scrub_and_add_sb (&from_sb, from); 283 sb_index = 1; 284 285 /* These variables are reset by input_scrub_push. Restore them 286 since we are, after all, still at the same point in the file. */ 287 logical_input_line = next_saved_file->logical_input_line; 288 logical_input_file = next_saved_file->logical_input_file; 289 } 290 291 void 292 input_scrub_close (void) 293 { 294 input_file_close (); 295 } 296 297 char * 298 input_scrub_next_buffer (char **bufp) 299 { 300 register char *limit; /*->just after last char of buffer. */ 301 302 if (sb_index >= 0) 303 { 304 if (sb_index >= from_sb.len) 305 { 306 sb_kill (&from_sb); 307 if (from_sb_is_expansion 308 ) 309 { 310 cond_finish_check (macro_nest); 311 #ifdef md_macro_end 312 /* Allow the target to clean up per-macro expansion 313 data. */ 314 md_macro_end (); 315 #endif 316 } 317 --macro_nest; 318 partial_where = NULL; 319 if (next_saved_file != NULL) 320 *bufp = input_scrub_pop (next_saved_file); 321 return partial_where; 322 } 323 324 partial_where = from_sb.ptr + from_sb.len; 325 partial_size = 0; 326 *bufp = from_sb.ptr + sb_index; 327 sb_index = from_sb.len; 328 return partial_where; 329 } 330 331 *bufp = buffer_start + BEFORE_SIZE; 332 333 if (partial_size) 334 { 335 memmove (buffer_start + BEFORE_SIZE, partial_where, 336 (unsigned int) partial_size); 337 memcpy (buffer_start + BEFORE_SIZE, save_source, AFTER_SIZE); 338 } 339 limit = input_file_give_next_buffer (buffer_start 340 + BEFORE_SIZE 341 + partial_size); 342 if (limit) 343 { 344 register char *p; /* Find last newline. */ 345 346 for (p = limit - 1; *p != '\n'; --p) 347 ; 348 ++p; 349 350 while (p <= buffer_start + BEFORE_SIZE) 351 { 352 int limoff; 353 354 limoff = limit - buffer_start; 355 buffer_length += input_file_buffer_size (); 356 buffer_start = xrealloc (buffer_start, 357 (BEFORE_SIZE 358 + 2 * buffer_length 359 + AFTER_SIZE)); 360 *bufp = buffer_start + BEFORE_SIZE; 361 limit = input_file_give_next_buffer (buffer_start + limoff); 362 363 if (limit == NULL) 364 { 365 as_warn (_("partial line at end of file ignored")); 366 partial_where = NULL; 367 if (next_saved_file) 368 *bufp = input_scrub_pop (next_saved_file); 369 return NULL; 370 } 371 372 for (p = limit - 1; *p != '\n'; --p) 373 ; 374 ++p; 375 } 376 377 partial_where = p; 378 partial_size = limit - p; 379 memcpy (save_source, partial_where, (int) AFTER_SIZE); 380 memcpy (partial_where, AFTER_STRING, (int) AFTER_SIZE); 381 } 382 else 383 { 384 partial_where = 0; 385 if (partial_size > 0) 386 { 387 as_warn (_("partial line at end of file ignored")); 388 } 389 390 /* Tell the listing we've finished the file. */ 391 LISTING_EOF (); 392 393 /* If we should pop to another file at EOF, do it. */ 394 if (next_saved_file) 395 { 396 *bufp = input_scrub_pop (next_saved_file); /* Pop state */ 397 /* partial_where is now correct to return, since we popped it. */ 398 } 399 } 400 return (partial_where); 401 } 402 403 /* The remaining part of this file deals with line numbers, error 404 messages and so on. Return TRUE if we opened any file. */ 405 406 int 407 seen_at_least_1_file (void) 408 { 409 return (physical_input_file != NULL); 410 } 411 412 void 413 bump_line_counters (void) 414 { 415 if (sb_index < 0) 416 { 417 ++physical_input_line; 418 if (logical_input_line >= 0) 419 ++logical_input_line; 420 } 421 } 422 423 /* Tells us what the new logical line number and file are. 424 If the line_number is -1, we don't change the current logical line 425 number. If it is -2, we decrement the logical line number (this is 426 to support the .appfile pseudo-op inserted into the stream by 427 do_scrub_chars). 428 If the fname is NULL, we don't change the current logical file name. 429 Returns nonzero if the filename actually changes. */ 430 431 int 432 new_logical_line (char *fname, /* DON'T destroy it! We point to it! */ 433 int line_number) 434 { 435 if (line_number >= 0) 436 logical_input_line = line_number; 437 else if (line_number == -2 && logical_input_line > 0) 438 --logical_input_line; 439 440 if (fname 441 && (logical_input_file == NULL 442 || strcmp (logical_input_file, fname))) 443 { 444 logical_input_file = fname; 445 return 1; 446 } 447 else 448 return 0; 449 } 450 451 /* Return the current file name and line number. 452 namep should be char * const *, but there are compilers which screw 453 up declarations like that, and it's easier to avoid it. */ 454 455 void 456 as_where (char **namep, unsigned int *linep) 457 { 458 if (logical_input_file != NULL 459 && (linep == NULL || logical_input_line >= 0)) 460 { 461 *namep = logical_input_file; 462 if (linep != NULL) 463 *linep = logical_input_line; 464 } 465 else if (physical_input_file != NULL) 466 { 467 *namep = physical_input_file; 468 if (linep != NULL) 469 *linep = physical_input_line; 470 } 471 else 472 { 473 *namep = 0; 474 if (linep != NULL) 475 *linep = 0; 476 } 477 } 478