gas/input-scrub.c

   1 /* input_scrub.c - Break up input buffers into whole numbers of lines.
   2    Copyright (C) 1987, 1990, 1991, 1992 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 2, 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
  18    the Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
  19
  20 #include <errno.h>              /* Need this to make errno declaration right */
  21 #include "as.h"
  22 #include "input-file.h"
  23 #include "sb.h"
  24
  25 /*
  26  * O/S independent module to supply buffers of sanitised source code
  27  * to rest of assembler.  We get sanitised input data of arbitrary length.
  28  * We break these buffers on line boundaries, recombine pieces that
  29  * were broken across buffers, and return a buffer of full lines to
  30  * the caller.
  31  * The last partial line begins the next buffer we build and return to caller.
  32  * The buffer returned to caller is preceeded by BEFORE_STRING and followed
  33  * by AFTER_STRING, as sentinels. The last character before AFTER_STRING
  34  * is a newline.
  35  * Also looks after line numbers, for e.g. error messages.
  36  */
  37
  38 /*
  39  * We don't care how filthy our buffers are, but our callers assume
  40  * that the following sanitation has already been done.
  41  *
  42  * No comments, reduce a comment to a space.
  43  * Reduce a tab to a space unless it is 1st char of line.
  44  * All multiple tabs and spaces collapsed into 1 char. Tab only
  45  *   legal if 1st char of line.
  46  * # line file statements converted to .line x;.file y; statements.
  47  * Escaped newlines at end of line: remove them but add as many newlines
  48  *   to end of statement as you removed in the middle, to synch line numbers.
  49  */
  50 \f
  51 #define BEFORE_STRING ("\n")
  52 #define AFTER_STRING ("\0")     /* memcpy of 0 chars might choke. */
  53 #define BEFORE_SIZE (1)
  54 #define AFTER_SIZE  (1)
  55
  56 static char *buffer_start;      /*->1st char of full buffer area. */
  57 static char *partial_where;     /*->after last full line in buffer. */
  58 static int partial_size;        /* >=0. Number of chars in partial line in buffer. */
  59 static char save_source[AFTER_SIZE];
  60 /* Because we need AFTER_STRING just after last */
  61 /* full line, it clobbers 1st part of partial */
  62 /* line. So we preserve 1st part of partial */
  63 /* line here. */
  64 static unsigned int buffer_length;      /* What is the largest size buffer that */
  65 /* input_file_give_next_buffer() could */
  66 /* return to us? */
  67
  68 /* The index into an sb structure we are reading from.  -1 if none.  */
  69 static int sb_index = -1;
  70
  71 /* If we are reading from an sb structure, this is it.  */
  72 static sb from_sb;
  73
  74 /* The number of nested sb structures we have included.  */
  75 static int macro_nest;
  76
  77 /* We can have more than one source file open at once, though the info for all
  78    but the latest one are saved off in a struct input_save.  These files remain
  79    open, so we are limited by the number of open files allowed by the
  80    underlying OS. We may also sequentially read more than one source file in an
  81    assembly. */
  82
  83 /* We must track the physical file and line number for error messages. We also
  84    track a "logical" file and line number corresponding to (C?)  compiler
  85    source line numbers.  Whenever we open a file we must fill in
  86    physical_input_file. So if it is NULL we have not opened any files yet. */
  87
  88 static char *physical_input_file;
  89 static char *logical_input_file;
  90
  91 typedef unsigned int line_numberT;      /* 1-origin line number in a source file. */
  92 /* A line ends in '\n' or eof. */
  93
  94 static line_numberT physical_input_line;
  95 static int logical_input_line;
  96
  97 /* Struct used to save the state of the input handler during include files */
  98 struct input_save
  99   {
 100     char *buffer_start;
 101     char *partial_where;
 102     int partial_size;
 103     char save_source[AFTER_SIZE];
 104     unsigned int buffer_length;
 105     char *physical_input_file;
 106     char *logical_input_file;
 107     line_numberT physical_input_line;
 108     int logical_input_line;
 109     int sb_index;
 110     sb from_sb;
 111     struct input_save *next_saved_file; /* Chain of input_saves */
 112     char *input_file_save;      /* Saved state of input routines */
 113     char *saved_position;       /* Caller's saved position in buf */
 114   };
 115
 116 static struct input_save *input_scrub_push PARAMS ((char *saved_position));
 117 static char *input_scrub_pop PARAMS ((struct input_save *arg));
 118 static void as_1_char PARAMS ((unsigned int c, FILE * stream));
 119
 120 /* Saved information about the file that .include'd this one.  When we hit EOF,
 121    we automatically pop to that file. */
 122
 123 static struct input_save *next_saved_file;
 124
 125 /* Push the state of input reading and scrubbing so that we can #include.
 126    The return value is a 'void *' (fudged for old compilers) to a save
 127    area, which can be restored by passing it to input_scrub_pop(). */
 128 static struct input_save *
 129 input_scrub_push (saved_position)
 130      char *saved_position;
 131 {
 132   register struct input_save *saved;
 133
 134   saved = (struct input_save *) xmalloc (sizeof *saved);
 135
 136   saved->saved_position = saved_position;
 137   saved->buffer_start = buffer_start;
 138   saved->partial_where = partial_where;
 139   saved->partial_size = partial_size;
 140   saved->buffer_length = buffer_length;
 141   saved->physical_input_file = physical_input_file;
 142   saved->logical_input_file = logical_input_file;
 143   saved->physical_input_line = physical_input_line;
 144   saved->logical_input_line = logical_input_line;
 145   saved->sb_index = sb_index;
 146   saved->from_sb = from_sb;
 147   memcpy (saved->save_source, save_source, sizeof (save_source));
 148   saved->next_saved_file = next_saved_file;
 149   saved->input_file_save = input_file_push ();
 150
 151   input_file_begin ();          /* Reinitialize! */
 152   logical_input_line = -1;
 153   logical_input_file = (char *) NULL;
 154   buffer_length = input_file_buffer_size ();
 155
 156   buffer_start = xmalloc ((BEFORE_SIZE + buffer_length + buffer_length + AFTER_SIZE));
 157   memcpy (buffer_start, BEFORE_STRING, (int) BEFORE_SIZE);
 158
 159   return saved;
 160 }                               /* input_scrub_push() */
 161
 162 static char *
 163 input_scrub_pop (saved)
 164      struct input_save *saved;
 165 {
 166   char *saved_position;
 167
 168   input_scrub_end ();           /* Finish off old buffer */
 169
 170   input_file_pop (saved->input_file_save);
 171   saved_position = saved->saved_position;
 172   buffer_start = saved->buffer_start;
 173   buffer_length = saved->buffer_length;
 174   physical_input_file = saved->physical_input_file;
 175   logical_input_file = saved->logical_input_file;
 176   physical_input_line = saved->physical_input_line;
 177   logical_input_line = saved->logical_input_line;
 178   sb_index = saved->sb_index;
 179   from_sb = saved->from_sb;
 180   partial_where = saved->partial_where;
 181   partial_size = saved->partial_size;
 182   next_saved_file = saved->next_saved_file;
 183   memcpy (save_source, saved->save_source, sizeof (save_source));
 184
 185   free (saved);
 186   return saved_position;
 187 }
 188 \f
 189
 190 void
 191 input_scrub_begin ()
 192 {
 193   know (strlen (BEFORE_STRING) == BEFORE_SIZE);
 194   know (strlen (AFTER_STRING) == AFTER_SIZE || (AFTER_STRING[0] == '\0' && AFTER_SIZE == 1));
 195
 196   input_file_begin ();
 197
 198   buffer_length = input_file_buffer_size ();
 199
 200   buffer_start = xmalloc ((BEFORE_SIZE + buffer_length + buffer_length + AFTER_SIZE));
 201   memcpy (buffer_start, BEFORE_STRING, (int) BEFORE_SIZE);
 202
 203   /* Line number things. */
 204   logical_input_line = -1;
 205   logical_input_file = (char *) NULL;
 206   physical_input_file = NULL;   /* No file read yet. */
 207   next_saved_file = NULL;       /* At EOF, don't pop to any other file */
 208   do_scrub_begin ();
 209 }
 210
 211 void
 212 input_scrub_end ()
 213 {
 214   if (buffer_start)
 215     {
 216       free (buffer_start);
 217       buffer_start = 0;
 218       input_file_end ();
 219     }
 220 }
 221
 222 /* Start reading input from a new file. */
 223
 224 char *                          /* Return start of caller's part of buffer. */
 225 input_scrub_new_file (filename)
 226      char *filename;
 227 {
 228   input_file_open (filename, !flag_no_comments);
 229   physical_input_file = filename[0] ? filename : "{standard input}";
 230   physical_input_line = 0;
 231
 232   partial_size = 0;
 233   return (buffer_start + BEFORE_SIZE);
 234 }
 235
 236
 237 /* Include a file from the current file.  Save our state, cause it to
 238    be restored on EOF, and begin handling a new file.  Same result as
 239    input_scrub_new_file. */
 240
 241 char *
 242 input_scrub_include_file (filename, position)
 243      char *filename;
 244      char *position;
 245 {
 246   next_saved_file = input_scrub_push (position);
 247   return input_scrub_new_file (filename);
 248 }
 249
 250 /* Start getting input from an sb structure.  This is used when
 251    expanding a macro.  */
 252
 253 void
 254 input_scrub_include_sb (from, position)
 255      sb *from;
 256      char *position;
 257 {
 258   if (macro_nest > max_macro_nest)
 259     as_fatal ("macros nested too deeply");
 260   ++macro_nest;
 261
 262   next_saved_file = input_scrub_push (position);
 263
 264   sb_new (&from_sb);
 265   /* Add the sentinel required by read.c.  */
 266   sb_add_char (&from_sb, '\n');
 267   sb_add_sb (&from_sb, from);
 268   sb_index = 1;
 269
 270   /* These variables are reset by input_scrub_push.  Restore them
 271      since we are, after all, still at the same point in the file.  */
 272   logical_input_line = next_saved_file->logical_input_line;
 273   logical_input_file = next_saved_file->logical_input_file;
 274 }
 275
 276 void
 277 input_scrub_close ()
 278 {
 279   input_file_close ();
 280 }
 281
 282 char *
 283 input_scrub_next_buffer (bufp)
 284      char **bufp;
 285 {
 286   register char *limit;         /*->just after last char of buffer. */
 287
 288   if (sb_index >= 0)
 289     {
 290       if (sb_index >= from_sb.len)
 291         {
 292           sb_kill (&from_sb);
 293           --macro_nest;
 294           partial_where = NULL;
 295           if (next_saved_file != NULL)
 296             *bufp = input_scrub_pop (next_saved_file);
 297           return partial_where;
 298         }
 299
 300       partial_where = from_sb.ptr + from_sb.len;
 301       partial_size = 0;
 302       *bufp = from_sb.ptr + sb_index;
 303       sb_index = from_sb.len;
 304       return partial_where;
 305     }
 306
 307   *bufp = buffer_start + BEFORE_SIZE;
 308
 309   if (partial_size)
 310     {
 311       memcpy (buffer_start + BEFORE_SIZE, partial_where,
 312               (unsigned int) partial_size);
 313       memcpy (buffer_start + BEFORE_SIZE, save_source, AFTER_SIZE);
 314     }
 315   limit = input_file_give_next_buffer (buffer_start
 316                                        + BEFORE_SIZE
 317                                        + partial_size);
 318   if (limit)
 319     {
 320       register char *p;         /* Find last newline. */
 321
 322       for (p = limit; *--p != '\n';);;
 323       ++p;
 324       if (p <= buffer_start + BEFORE_SIZE)
 325         {
 326           as_fatal ("Source line too long. Please change file %s then rebuild assembler.", __FILE__);
 327         }
 328       partial_where = p;
 329       partial_size = limit - p;
 330       memcpy (save_source, partial_where, (int) AFTER_SIZE);
 331       memcpy (partial_where, AFTER_STRING, (int) AFTER_SIZE);
 332     }
 333   else
 334     {
 335       partial_where = 0;
 336       if (partial_size > 0)
 337         {
 338           as_warn ("Partial line at end of file ignored");
 339         }
 340       /* If we should pop to another file at EOF, do it. */
 341       if (next_saved_file)
 342         {
 343           *bufp = input_scrub_pop (next_saved_file);    /* Pop state */
 344           /* partial_where is now correct to return, since we popped it. */
 345         }
 346     }
 347   return (partial_where);
 348 }                               /* input_scrub_next_buffer() */
 349 \f
 350 /*
 351  * The remaining part of this file deals with line numbers, error
 352  * messages and so on.
 353  */
 354
 355
 356 int
 357 seen_at_least_1_file ()         /* TRUE if we opened any file. */
 358 {
 359   return (physical_input_file != NULL);
 360 }
 361
 362 void
 363 bump_line_counters ()
 364 {
 365   if (sb_index < 0)
 366     {
 367       ++physical_input_line;
 368       if (logical_input_line >= 0)
 369         ++logical_input_line;
 370     }
 371 }
 372 \f
 373 /*
 374  *                      new_logical_line()
 375  *
 376  * Tells us what the new logical line number and file are.
 377  * If the line_number is -1, we don't change the current logical line
 378  * number.  If it is -2, we decrement the logical line number (this is
 379  * to support the .appfile pseudo-op inserted into the stream by
 380  * do_scrub_chars).
 381  * If the fname is NULL, we don't change the current logical file name.
 382  */
 383 void
 384 new_logical_line (fname, line_number)
 385      char *fname;               /* DON'T destroy it! We point to it! */
 386      int line_number;
 387 {
 388   if (fname)
 389     {
 390       logical_input_file = fname;
 391     }                           /* if we have a file name */
 392
 393   if (line_number >= 0)
 394     logical_input_line = line_number;
 395   else if (line_number == -2 && logical_input_line > 0)
 396     --logical_input_line;
 397 }                               /* new_logical_line() */
 398 \f
 399 /*
 400  *                      a s _ w h e r e ()
 401  *
 402  * Return the current file name and line number.
 403  * namep should be char * const *, but there are compilers which screw
 404  * up declarations like that, and it's easier to avoid it.
 405  */
 406 void
 407 as_where (namep, linep)
 408      char **namep;
 409      unsigned int *linep;
 410 {
 411   if (logical_input_file != NULL
 412       && (linep == NULL || logical_input_line >= 0))
 413     {
 414       *namep = logical_input_file;
 415       if (linep != NULL)
 416         *linep = logical_input_line;
 417     }
 418   else if (physical_input_file != NULL)
 419     {
 420       *namep = physical_input_file;
 421       if (linep != NULL)
 422         *linep = physical_input_line;
 423     }
 424   else
 425     {
 426       *namep = 0;
 427       if (linep != NULL)
 428         *linep = 0;
 429     }
 430 }                               /* as_where() */
 431 \f
 432
 433
 434
 435 /*
 436  *                      a s _ h o w m u c h ()
 437  *
 438  * Output to given stream how much of line we have scanned so far.
 439  * Assumes we have scanned up to and including input_line_pointer.
 440  * No free '\n' at end of line.
 441  */
 442 void
 443 as_howmuch (stream)
 444      FILE *stream;              /* Opened for write please. */
 445 {
 446   register char *p;             /* Scan input line. */
 447   /* register char c; JF unused */
 448
 449   for (p = input_line_pointer - 1; *p != '\n'; --p)
 450     {
 451     }
 452   ++p;                          /* p->1st char of line. */
 453   for (; p <= input_line_pointer; p++)
 454     {
 455       /* Assume ASCII. EBCDIC & other micro-computer char sets ignored. */
 456       as_1_char ((unsigned char) *p, stream);
 457     }
 458 }
 459
 460 static void
 461 as_1_char (c, stream)
 462      unsigned int c;
 463      FILE *stream;
 464 {
 465   if (c > 127)
 466     {
 467       (void) putc ('%', stream);
 468       c -= 128;
 469     }
 470   if (c < 32)
 471     {
 472       (void) putc ('^', stream);
 473       c += '@';
 474     }
 475   (void) putc (c, stream);
 476 }
 477
 478 /* end of input_scrub.c */