mdw@git.distorted.org.uk Git - become/blob - src/utils.c

   1 /* -*-c-*-
   2  *
   3  * $Id: utils.c,v 1.6 1998/01/12 16:46:47 mdw Exp $
   4  *
   5  * Miscellaneous useful bits of code.
   6  *
   7  * (c) 1998 Mark Wooding
   8  */
   9
  10 /*----- Licensing notice --------------------------------------------------*
  11  *
  12  * This file is part of `become'
  13  *
  14  * `Become' is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2 of the License, or
  17  * (at your option) any later version.
  18  *
  19  * `Become' is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with `become'; if not, write to the Free Software Foundation,
  26  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  27  */
  28
  29 /*----- Revision history --------------------------------------------------*
  30  *
  31  * $Log: utils.c,v $
  32  * Revision 1.6  1998/01/12 16:46:47  mdw
  33  * Fix copyright date.
  34  *
  35  * Revision 1.5  1997/09/17  10:24:47  mdw
  36  * Flush output before and after writing memory tracking information.
  37  *
  38  * Revision 1.4  1997/09/08  13:43:54  mdw
  39  * Flush tracedump file after each `interesting' write.
  40  *
  41  * Revision 1.3  1997/08/20  16:25:37  mdw
  42  * Add some simple `malloc' tracking.
  43  *
  44  * Revision 1.2  1997/08/04 10:24:26  mdw
  45  * Sources placed under CVS control.
  46  *
  47  * Revision 1.1  1997/07/21  13:47:42  mdw
  48  * Initial revision
  49  *
  50  */
  51
  52 /*----- Header files ------------------------------------------------------*/
  53
  54 /* --- ANSI headers --- */
  55
  56 #include <ctype.h>
  57 #include <stdarg.h>
  58 #include <stdio.h>
  59 #include <stdlib.h>
  60 #include <string.h>
  61
  62 /* --- Local headers --- */
  63
  64 #include "config.h"
  65 #include "utils.h"
  66
  67 /*----- Program name handling ---------------------------------------------*/
  68
  69 /* --- Static data --- */
  70
  71 static const char *myname = 0;          /* What's my name? */
  72
  73 /* --- @quis@ --- *
  74  *
  75  * Arguments:   ---
  76  *
  77  * Returns:     Pointer to the program name.
  78  *
  79  * Use:         Returns the program name.
  80  */
  81
  82 const char *quis(void)
  83 {
  84   return (myname);
  85 }
  86
  87 /* --- @ego@ --- *
  88  *
  89  * Arguments:   @const char *p@ = pointer to program name
  90  *
  91  * Returns:     ---
  92  *
  93  * Use:         Tells the utils library what the program's name is.
  94  */
  95
  96 #ifndef PATHSEP
  97 #  if defined(__riscos)
  98 #    define PATHSEP '.'
  99 #  elif defined(__unix) || defined(unix)
 100 #    define PATHSEP '/'
 101 #  else
 102 #    define PATHSEP '\\'
 103 #  endif
 104 #endif
 105
 106 void ego(const char *p)
 107 {
 108   const char *q = p;
 109   while (*q) {
 110     if (*q++ == PATHSEP)
 111       p = q;
 112   }
 113   myname = p;
 114 }
 115
 116 /*----- Error reporting ---------------------------------------------------*/
 117
 118 /* --- @moan@ --- *
 119  *
 120  * Arguments:   @const char *f@ = a @printf@-style format string
 121  *              @...@ = other arguments
 122  *
 123  * Returns:     ---
 124  *
 125  * Use:         Reports an error.
 126  */
 127
 128 void moan(const char *f, ...)
 129 {
 130   va_list ap;
 131   va_start(ap, f);
 132   fprintf(stderr, "%s: ", myname);
 133   vfprintf(stderr, f, ap);
 134   va_end(ap);
 135   putc('\n', stderr);
 136 }
 137
 138 /* --- @die@ --- *
 139  *
 140  * Arguments:   @const char *f@ = a @printf@-style format string
 141  *              @...@ = other arguments
 142  *
 143  * Returns:     Never.
 144  *
 145  * Use:         Reports an error and hari-kiris.  Like @moan@ above, only
 146  *              more permanent.
 147  */
 148
 149 void die(const char *f, ...)
 150 {
 151   va_list ap;
 152   va_start(ap, f);
 153   fprintf(stderr, "%s: ", myname);
 154   vfprintf(stderr, f, ap);
 155   va_end(ap);
 156   putc('\n', stderr);
 157   exit(EXIT_FAILURE);
 158 }
 159
 160 /*----- Trace messages ----------------------------------------------------*/
 161
 162 #if defined(TRACING) || !defined(NDEBUG)
 163
 164 /* --- Static data --- */
 165
 166 static FILE *tracefp = 0;               /* Where does debugging go? */
 167 static unsigned int tracelvl = 0;       /* How much tracing gets done? */
 168
 169 /* --- @trace@ --- *
 170  *
 171  * Arguments:   @unsigned int lvl@ = trace level for output
 172  *              @const char *f@ = a @printf@-style format string
 173  *              @...@ = other arguments
 174  *
 175  * Returns:     ---
 176  *
 177  * Use:         Reports a message to the trace output.
 178  */
 179
 180 void trace(unsigned int lvl, const char *f, ...)
 181 {
 182   va_list ap;
 183   if ((lvl & tracing()) == 0)
 184     return;
 185   va_start(ap, f);
 186   fprintf(tracefp, "*** %s: ", myname);
 187   vfprintf(tracefp, f, ap);
 188   va_end(ap);
 189   putc('\n', tracefp);
 190   fflush(tracefp);
 191 }
 192
 193 /* --- @traceblk@ --- *
 194  *
 195  * Arguments:   @unsigned int lvl@ = trace level for output
 196  *              @const char *hdr@ = some header string to write
 197  *              @const void *blk@ = pointer to a block of memory to dump
 198  *              @size_t sz@ = size of the block of memory
 199  *
 200  * Returns:     ---
 201  *
 202  * Use:         Dumps the contents of a block to the trace output.
 203  */
 204
 205 void traceblk(unsigned int lvl, const char *hdr, const void *blk, size_t sz)
 206 {
 207   const unsigned char *p = blk;
 208   size_t i;
 209   unsigned long o = 0;
 210   size_t c;
 211
 212   /* --- Skip if the trace level is too high --- */
 213
 214   if ((lvl & tracing()) == 0)
 215     return;
 216
 217   /* --- Now start work --- */
 218
 219   fprintf(tracefp, "*** %s: %s\n", myname, hdr);
 220
 221   while (sz) {
 222     fprintf(tracefp, "*** %s:   %08lu : ", myname, o);
 223     for (i = 0; i < 8; i++) {
 224       if (i < sz)
 225         fprintf(tracefp, "%02x ", p[i]);
 226       else
 227         fputs("** ", tracefp);
 228     }
 229     fputs(": ", tracefp);
 230     for (i = 0; i < 8; i++) {
 231       if (i < sz)
 232         fputc(isprint(p[i]) ? p[i] : '.', tracefp);
 233       else
 234         fputc('*', tracefp);
 235     }
 236     fputc('\n', tracefp);
 237     c = (sz >= 8) ? 8 : sz;
 238     sz -= c, p += c, o += c;
 239   }
 240   fflush(tracefp);
 241 }
 242
 243 /* --- @traceon@ --- *
 244  *
 245  * Arguments:   @FILE *fp@ = a file to trace on
 246  *              @unsigned int lvl@ = trace level to set
 247  *
 248  * Returns:     ---
 249  *
 250  * Use:         Enables tracing to a file.
 251  */
 252
 253 void traceon(FILE *fp, unsigned int lvl)
 254 {
 255   tracefp = fp;
 256   if (!tracelvl)
 257     tracelvl = lvl;
 258 }
 259
 260 /* --- @tracesetlvl@ --- *
 261  *
 262  * Arguments:   @unsigned int lvl@ = trace level to set
 263  *
 264  * Returns:     ---
 265  *
 266  * Use:         Sets the tracing level.
 267  */
 268
 269 void tracesetlvl(unsigned int lvl) { tracelvl = lvl; }
 270
 271 /* --- @tracing@ --- *
 272  *
 273  * Arguments:   ---
 274  *
 275  * Returns:     Zero if not tracing, tracing level if tracing.
 276  *
 277  * Use:         Informs the caller whether tracing is enabled.
 278  */
 279
 280 unsigned int tracing(void) { return (tracefp ? tracelvl : 0u); }
 281
 282 #endif
 283
 284 /*----- Memory management functions ---------------------------------------*/
 285
 286 /* --- @xmalloc@ --- *
 287  *
 288  * Arguments:   @size_t sz@ = size of block to allocate
 289  *
 290  * Returns:     Pointer to allocated block.
 291  *
 292  * Use:         Allocates memory.  If the memory isn't available, we don't
 293  *              hang aroung long enough for a normal function return.
 294  */
 295
 296 void *xmalloc(size_t sz)
 297 {
 298   void *p = malloc(sz);
 299   if (!p)
 300     die("not enough memory");
 301   return (p);
 302 }
 303
 304 /* --- @xstrdup@ --- *
 305  *
 306  * Arguments:   @const char *s@ = pointer to a string
 307  *
 308  * Returns:     Pointer to a copy of the string.
 309  *
 310  * Use:         Copies a string (like @strdup@ would, if it existed).
 311  */
 312
 313 char *xstrdup(const char *s)
 314 {
 315   size_t sz = strlen(s) + 1;
 316   char *p = xmalloc(sz);
 317   memcpy(p, s, sz);
 318   return (p);
 319 }
 320
 321 /* --- @xrealloc@ --- *
 322  *
 323  * Arguments:   @void *p@ = pointer to a block of memory
 324  *              @size_t sz@ = new size desired for the block
 325  *
 326  * Returns:     Pointer to the resized memory block (which is almost
 327  *              certainly not in the same place any more).
 328  *
 329  * Use:         Resizes a memory block.
 330  */
 331
 332 void *xrealloc(void *p, size_t sz)
 333 {
 334   p = realloc(p, sz);
 335   if (!p)
 336     die("not enough memory");
 337   return (p);
 338 }
 339
 340 /*----- Simple memory use tracking ----------------------------------------*/
 341
 342 #ifdef TRACK_MALLOC
 343
 344 /*#define TRACK_VERBOSE*/
 345
 346 /* --- A type to record a size and have a nice alignment --- */
 347
 348 typedef union szblock {
 349   struct {
 350     union szblock *next;
 351     union szblock *prev;
 352     size_t sz;
 353   } x;
 354   long double _ld;
 355   void *_p;
 356 } szblock;
 357
 358 /* --- Static data --- */
 359
 360 static unsigned int memused = 0;
 361 static szblock *memlist;
 362
 363 /* --- @track_malloc@ --- *
 364  *
 365  * Arguments:   @size_t sz@ = size requested
 366  *
 367  * Returns:     Pointer to allocated space, or null
 368  *
 369  * Use:         Allocates memory, and tracks how much is allocated.
 370  */
 371
 372 void *track_malloc(size_t sz)
 373 {
 374   szblock *q = (malloc)(sz + sizeof(szblock));
 375   if (q) {
 376     memused += sz;
 377 #ifdef TRACK_VERBOSE
 378     fflush(0);
 379     printf("[%p] allocated %lu\n", (void *)(q + 1), (unsigned long)sz);
 380     fflush(stdout);
 381 #endif
 382     q->x.sz = sz;
 383     q->x.next = memlist;
 384     q->x.prev = 0;
 385     if (q->x.next)
 386       q->x.next->x.prev = q;
 387     memlist = q;
 388     return (q + 1);
 389   }
 390   return (0);
 391 }
 392
 393 /* --- @track_free@ --- *
 394  *
 395  * Arguments:   @void *p@ = pointer to an allocated block
 396  *
 397  * Returns:     ---
 398  *
 399  * Use:         Frees memory, and tracks how much is still allocated.
 400  */
 401
 402 void track_free(void *p)
 403 {
 404   szblock *q;
 405
 406   if (!p)
 407     return;
 408   q = (szblock *)p - 1;
 409 #ifdef TRACK_VERBOSE
 410   fflush(0);
 411   printf("[%p] freed %lu\n", (void *)(q + 1), (unsigned long)q->x.sz);
 412   fflush(stdout);
 413 #endif
 414   if (q->x.next)
 415     q->x.next->x.prev = q->x.prev;
 416   if (q->x.prev)
 417     q->x.prev->x.next = q->x.next;
 418   else
 419     memlist = q->x.next;
 420   memused -= q->x.sz;
 421   (free)(q);
 422 }
 423
 424 /* --- @track_realloc@ --- *
 425  *
 426  * Arguments:   @void *p@ = pointer to an allocated block
 427  *              @size_t sz@ = how big it wants to be
 428  *
 429  * Returns:     Pointer to the new block.
 430  *
 431  * Use:         Reallocates a block, tracking how much memory is still
 432  *              available.
 433  */
 434
 435 void *track_realloc(void *p, size_t sz)
 436 {
 437   size_t osz;
 438   szblock *q, *qq;
 439   if (p) {
 440     q = (szblock *)p - 1;
 441     osz = q->x.sz;
 442     if (q->x.next)
 443       q->x.next->x.prev = q->x.prev;
 444     if (q->x.prev)
 445       q->x.prev->x.next = q->x.next;
 446     else
 447       memlist = q->x.next;
 448   } else {
 449     q = 0;
 450     osz = 0;
 451   }
 452   qq = (realloc)(q, sz + sizeof(szblock));
 453   if (qq) {
 454 #ifdef TRACK_VERBOSE
 455     fflush(0);
 456     printf("[%p->%p] reallocated %lu -> %lu\n",
 457            (void *)(q + 1), (void *)(qq + 1),
 458            (unsigned long)osz, (unsigned long)sz);
 459     fflush(stdout);
 460 #endif
 461     qq->x.sz = sz;
 462     qq->x.next = memlist;
 463     qq->x.prev = 0;
 464     if (qq->x.next)
 465       qq->x.next->x.prev = qq;
 466     memlist = qq;
 467     memused += sz - osz;
 468     qq->x.sz = sz;
 469     return (qq + 1);
 470   }
 471   return (0);
 472 }
 473
 474 /* --- @track_memused@ --- *
 475  *
 476  * Arguments:   ---
 477  *
 478  * Returns:     A count of how much memory is used currently.
 479  *
 480  * Use:         Returns the amount of memory which the @track_@-functions
 481  *              above have counted as being currently allocated.
 482  */
 483
 484 unsigned long track_memused(void)
 485 {
 486   return (memused);
 487 }
 488
 489 /* --- @track_memlist@ --- *
 490  *
 491  * Arguments:   ---
 492  *
 493  * Returns:     ---
 494  *
 495  * Use:         Dumps a list of allocated blocks to standard output.
 496  */
 497
 498 void track_memlist(void)
 499 {
 500   szblock *q = memlist;
 501   fflush(0);
 502   printf("listing blocks:\n");
 503   while (q) {
 504     printf("... [%p] %lu\n", (void *)(q + 1), (unsigned long)q->x.sz);
 505     q = q->x.next;
 506   }
 507   printf("done\n");
 508   fflush(stdout);
 509 }
 510
 511 #endif
 512
 513 /*----- That's all, folks -------------------------------------------------*/