include/nasmlib.h

   1 /* ----------------------------------------------------------------------- *
   2  *
   3  *   Copyright 1996-2017 The NASM Authors - All Rights Reserved
   4  *   See the file AUTHORS included with the NASM distribution for
   5  *   the specific copyright holders.
   6  *
   7  *   Redistribution and use in source and binary forms, with or without
   8  *   modification, are permitted provided that the following
   9  *   conditions are met:
  10  *
  11  *   * Redistributions of source code must retain the above copyright
  12  *     notice, this list of conditions and the following disclaimer.
  13  *   * Redistributions in binary form must reproduce the above
  14  *     copyright notice, this list of conditions and the following
  15  *     disclaimer in the documentation and/or other materials provided
  16  *     with the distribution.
  17  *
  18  *     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
  19  *     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
  20  *     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  21  *     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  22  *     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  23  *     CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  24  *     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  25  *     NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  26  *     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  *     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  28  *     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  29  *     OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
  30  *     EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  31  *
  32  * ----------------------------------------------------------------------- */
  33
  34 /*
  35  * nasmlib.h    header file for nasmlib.c
  36  */
  37
  38 #ifndef NASM_NASMLIB_H
  39 #define NASM_NASMLIB_H
  40
  41 #include "compiler.h"
  42
  43 #include <ctype.h>
  44 #include <stdio.h>
  45 #include <string.h>
  46 #ifdef HAVE_STRINGS_H
  47 # include <strings.h>
  48 #endif
  49
  50 /*
  51  * tolower table -- avoids a function call on some platforms.
  52  * NOTE: unlike the tolower() function in ctype, EOF is *NOT*
  53  * a permitted value, for obvious reasons.
  54  */
  55 void tolower_init(void);
  56 extern unsigned char nasm_tolower_tab[256];
  57 #define nasm_tolower(x) nasm_tolower_tab[(unsigned char)(x)]
  58
  59 /* Wrappers around <ctype.h> functions */
  60 /* These are only valid for values that cannot include EOF */
  61 #define nasm_isspace(x)  isspace((unsigned char)(x))
  62 #define nasm_isalpha(x)  isalpha((unsigned char)(x))
  63 #define nasm_isdigit(x)  isdigit((unsigned char)(x))
  64 #define nasm_isalnum(x)  isalnum((unsigned char)(x))
  65 #define nasm_isxdigit(x) isxdigit((unsigned char)(x))
  66
  67 /*
  68  * Wrappers around malloc, realloc and free. nasm_malloc will
  69  * fatal-error and die rather than return NULL; nasm_realloc will
  70  * do likewise, and will also guarantee to work right on being
  71  * passed a NULL pointer; nasm_free will do nothing if it is passed
  72  * a NULL pointer.
  73  */
  74 void * safe_malloc(1) nasm_malloc(size_t);
  75 void * safe_malloc(1) nasm_zalloc(size_t);
  76 void * safe_malloc2(1,2) nasm_calloc(size_t, size_t);
  77 void * safe_realloc(2) nasm_realloc(void *, size_t);
  78 void nasm_free(void *);
  79 char * safe_alloc nasm_strdup(const char *);
  80 char * safe_alloc nasm_strndup(const char *, size_t);
  81
  82 /* Assert the argument is a pointer without evaluating it */
  83 #define nasm_assert_pointer(p) ((void)sizeof(*(p)))
  84
  85 #define nasm_new(p) ((p) = nasm_zalloc(sizeof(*(p))))
  86 #define nasm_newn(p,n) ((p) = nasm_calloc(sizeof(*(p)),(n)))
  87 /*
  88  * This is broken on platforms where there are pointers which don't
  89  * match void * in their internal layout.  It unfortunately also
  90  * loses any "const" part of the argument, although hopefully the
  91  * compiler will warn in that case.
  92  */
  93 #define nasm_delete(p)                                          \
  94     do {                                                        \
  95         void **_pp = (void **)&(p);                             \
  96         nasm_assert_pointer(p);                                 \
  97         nasm_free(*_pp);                                        \
  98         *_pp = NULL;                                            \
  99     } while (0)
 100 #define nasm_zero(x) (memset(&(x), 0, sizeof(x)))
 101 #define nasm_zeron(p,n) (memset((p), 0, (n)*sizeof(*(p))))
 102
 103 /*
 104  * Wrappers around fread()/fwrite() which fatal-errors on failure.
 105  * For fread(), only use this if EOF is supposed to be a fatal error!
 106  */
 107 void nasm_read(void *, size_t, FILE *);
 108 void nasm_write(const void *, size_t, FILE *);
 109
 110 /*
 111  * NASM assert failure
 112  */
 113 no_return nasm_assert_failed(const char *, int, const char *);
 114 #define nasm_assert(x)                                          \
 115     do {                                                        \
 116         if (unlikely(!(x)))                                     \
 117             nasm_assert_failed(__FILE__,__LINE__,#x);           \
 118     } while (0)
 119
 120 /*
 121  * NASM failure at build time if the argument is false
 122  */
 123 #ifdef static_assert
 124 # define nasm_static_assert(x) static_assert(x, #x)
 125 #elif defined(HAVE_FUNC_ATTRIBUTE_ERROR) && defined(__OPTIMIZE__)
 126 # define nasm_static_assert(x)                                           \
 127     if (!(x)) {                                                         \
 128         extern void __attribute__((error("assertion " #x " failed")))   \
 129             _nasm_static_fail(void);                                    \
 130         _nasm_static_fail();                                            \
 131     }
 132 #else
 133 /* See http://www.drdobbs.com/compile-time-assertions/184401873 */
 134 # define nasm_static_assert(x) \
 135     do { enum { _static_assert_failed = 1/(!!(x)) }; } while (0)
 136 #endif
 137
 138 /* Utility function to generate a string for an invalid enum */
 139 const char *invalid_enum_str(int);
 140
 141 /*
 142  * ANSI doesn't guarantee the presence of `stricmp' or
 143  * `strcasecmp'.
 144  */
 145 #if defined(HAVE_STRCASECMP)
 146 #define nasm_stricmp strcasecmp
 147 #elif defined(HAVE_STRICMP)
 148 #define nasm_stricmp stricmp
 149 #else
 150 int pure_func nasm_stricmp(const char *, const char *);
 151 #endif
 152
 153 #if defined(HAVE_STRNCASECMP)
 154 #define nasm_strnicmp strncasecmp
 155 #elif defined(HAVE_STRNICMP)
 156 #define nasm_strnicmp strnicmp
 157 #else
 158 int pure_func nasm_strnicmp(const char *, const char *, size_t);
 159 #endif
 160
 161 int pure_func nasm_memicmp(const char *, const char *, size_t);
 162
 163 #if defined(HAVE_STRSEP)
 164 #define nasm_strsep strsep
 165 #else
 166 char *nasm_strsep(char **stringp, const char *delim);
 167 #endif
 168
 169 #ifndef HAVE_DECL_STRNLEN
 170 size_t pure_func strnlen(const char *, size_t);
 171 #endif
 172
 173 /* This returns the numeric value of a given 'digit'. */
 174 #define numvalue(c)         ((c) >= 'a' ? (c) - 'a' + 10 : (c) >= 'A' ? (c) - 'A' + 10 : (c) - '0')
 175
 176 /*
 177  * Convert a string into a number, using NASM number rules. Sets
 178  * `*error' to true if an error occurs, and false otherwise.
 179  */
 180 int64_t readnum(char *str, bool *error);
 181
 182 /*
 183  * Convert a character constant into a number. Sets
 184  * `*warn' to true if an overflow occurs, and false otherwise.
 185  * str points to and length covers the middle of the string,
 186  * without the quotes.
 187  */
 188 int64_t readstrnum(char *str, int length, bool *warn);
 189
 190 /*
 191  * seg_init: Initialise the segment-number allocator.
 192  * seg_alloc: allocate a hitherto unused segment number.
 193  */
 194 void pure_func seg_init(void);
 195 int32_t pure_func seg_alloc(void);
 196
 197 /*
 198  * many output formats will be able to make use of this: a standard
 199  * function to add an extension to the name of the input file
 200  */
 201 void standard_extension(char *inname, char *outname, char *extension);
 202
 203 /*
 204  * Utility macros...
 205  *
 206  * This is a useful #define which I keep meaning to use more often:
 207  * the number of elements of a statically defined array.
 208  */
 209 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
 210
 211 /*
 212  * List handling
 213  *
 214  *  list_for_each - regular iterator over list
 215  *  list_for_each_safe - the same but safe against list items removal
 216  *  list_last - find the last element in a list
 217  */
 218 #define list_for_each(pos, head)                        \
 219     for (pos = head; pos; pos = pos->next)
 220 #define list_for_each_safe(pos, n, head)                \
 221     for (pos = head, n = (pos ? pos->next : NULL); pos; \
 222         pos = n, n = (n ? n->next : NULL))
 223 #define list_last(pos, head)                            \
 224     for (pos = head; pos && pos->next; pos = pos->next) \
 225         ;
 226 #define list_reverse(head, prev, next)                  \
 227     do {                                                \
 228         if (!head || !head->next)                       \
 229             break;                                      \
 230         prev = NULL;                                    \
 231         while (head) {                                  \
 232             next = head->next;                          \
 233             head->next = prev;                          \
 234             prev = head;                                \
 235             head = next;                                \
 236         }                                               \
 237         head = prev;                                    \
 238     } while (0)
 239
 240 /*
 241  * Power of 2 align helpers
 242  */
 243 #undef ALIGN_MASK               /* Some BSD flavors define these in system headers */
 244 #undef ALIGN
 245 #define ALIGN_MASK(v, mask)     (((v) + (mask)) & ~(mask))
 246 #define ALIGN(v, a)             ALIGN_MASK(v, (a) - 1)
 247 #define IS_ALIGNED(v, a)        (((v) & ((a) - 1)) == 0)
 248
 249 /*
 250  * some handy macros that will probably be of use in more than one
 251  * output format: convert integers into little-endian byte packed
 252  * format in memory
 253  */
 254
 255 #if X86_MEMORY
 256
 257 #define WRITECHAR(p,v)                          \
 258     do {                                        \
 259         *(uint8_t *)(p) = (v);                  \
 260         (p) += 1;                               \
 261     } while (0)
 262
 263 #define WRITESHORT(p,v)                         \
 264     do {                                        \
 265         *(uint16_t *)(p) = (v);                 \
 266         (p) += 2;                               \
 267     } while (0)
 268
 269 #define WRITELONG(p,v)                          \
 270     do {                                        \
 271         *(uint32_t *)(p) = (v);                 \
 272         (p) += 4;                               \
 273     } while (0)
 274
 275 #define WRITEDLONG(p,v)                         \
 276     do {                                        \
 277         *(uint64_t *)(p) = (v);                 \
 278         (p) += 8;                               \
 279     } while (0)
 280
 281 #define WRITEADDR(p,v,s)                        \
 282     do {                                        \
 283         uint64_t _wa_v = (v);                   \
 284         memcpy((p), &_wa_v, (s));               \
 285         (p) += (s);                             \
 286     } while (0)
 287
 288 #else /* !X86_MEMORY */
 289
 290 #define WRITECHAR(p,v)                          \
 291     do {                                        \
 292         uint8_t *_wc_p = (uint8_t *)(p);        \
 293         uint8_t _wc_v = (v);                    \
 294         _wc_p[0] = _wc_v;                       \
 295         (p) = (void *)(_wc_p + 1);              \
 296     } while (0)
 297
 298 #define WRITESHORT(p,v)                         \
 299     do {                                        \
 300         uint8_t *_ws_p = (uint8_t *)(p);        \
 301         uint16_t _ws_v = (v);                   \
 302         _ws_p[0] = _ws_v;                       \
 303         _ws_p[1] = _ws_v >> 8;                  \
 304         (p) = (void *)(_ws_p + 2);              \
 305     } while (0)
 306
 307 #define WRITELONG(p,v)                          \
 308     do {                                        \
 309         uint8_t *_wl_p = (uint8_t *)(p);        \
 310         uint32_t _wl_v = (v);                   \
 311         _wl_p[0] = _wl_v;                       \
 312         _wl_p[1] = _wl_v >> 8;                  \
 313         _wl_p[2] = _wl_v >> 16;                 \
 314         _wl_p[3] = _wl_v >> 24;                 \
 315         (p) = (void *)(_wl_p + 4);              \
 316     } while (0)
 317
 318 #define WRITEDLONG(p,v)                         \
 319     do {                                        \
 320         uint8_t *_wq_p = (uint8_t *)(p);        \
 321         uint64_t _wq_v = (v);                   \
 322         _wq_p[0] = _wq_v;                       \
 323         _wq_p[1] = _wq_v >> 8;                  \
 324         _wq_p[2] = _wq_v >> 16;                 \
 325         _wq_p[3] = _wq_v >> 24;                 \
 326         _wq_p[4] = _wq_v >> 32;                 \
 327         _wq_p[5] = _wq_v >> 40;                 \
 328         _wq_p[6] = _wq_v >> 48;                 \
 329         _wq_p[7] = _wq_v >> 56;                 \
 330         (p) = (void *)(_wq_p + 8);              \
 331     } while (0)
 332
 333 #define WRITEADDR(p,v,s)                        \
 334     do {                                        \
 335         int _wa_s = (s);                        \
 336         uint64_t _wa_v = (v);                   \
 337         while (_wa_s--) {                       \
 338             WRITECHAR(p,_wa_v);                 \
 339             _wa_v >>= 8;                        \
 340         }                                       \
 341     } while(0)
 342
 343 #endif
 344
 345 /*
 346  * and routines to do the same thing to a file
 347  */
 348 #define fwriteint8_t(d,f) putc(d,f)
 349 void fwriteint16_t(uint16_t data, FILE * fp);
 350 void fwriteint32_t(uint32_t data, FILE * fp);
 351 void fwriteint64_t(uint64_t data, FILE * fp);
 352 void fwriteaddr(uint64_t data, int size, FILE * fp);
 353
 354 /*
 355  * Binary search routine. Returns index into `array' of an entry
 356  * matching `string', or <0 if no match. `array' is taken to
 357  * contain `size' elements.
 358  *
 359  * bsi() is case sensitive, bsii() is case insensitive.
 360  */
 361 int bsi(const char *string, const char **array, int size);
 362 int bsii(const char *string, const char **array, int size);
 363
 364 /*
 365  * These functions are used to keep track of the source code file and name.
 366  */
 367 void src_init(void);
 368 void src_free(void);
 369 const char *src_set_fname(const char *newname);
 370 const char *src_get_fname(void);
 371 int32_t src_set_linnum(int32_t newline);
 372 int32_t src_get_linnum(void);
 373 /* Can be used when there is no need for the old information */
 374 void src_set(int32_t line, const char *filename);
 375 /*
 376  * src_get gets both the source file name and line.
 377  * It is also used if you maintain private status about the source location
 378  * It return 0 if the information was the same as the last time you
 379  * checked, -2 if the name changed and (new-old) if just the line changed.
 380  */
 381 int32_t src_get(int32_t *xline, const char **xname);
 382
 383 char *nasm_strcat(const char *one, const char *two);
 384
 385 char *nasm_skip_spaces(const char *p);
 386 char *nasm_skip_word(const char *p);
 387 char *nasm_zap_spaces_fwd(char *p);
 388 char *nasm_zap_spaces_rev(char *p);
 389 char *nasm_trim_spaces(char *p);
 390 char *nasm_get_word(char *p, char **tail);
 391 char *nasm_opt_val(char *p, char **opt, char **val);
 392
 393 /*
 394  * Converts a relative pathname rel_path into an absolute path name.
 395  *
 396  * The buffer returned must be freed by the caller
 397  */
 398 char * safe_alloc nasm_realpath(const char *rel_path);
 399
 400 /*
 401  * Path-splitting and merging functions
 402  */
 403 char * safe_alloc nasm_dirname(const char *path);
 404 char * safe_alloc nasm_basename(const char *path);
 405 char * safe_alloc nasm_catfile(const char *dir, const char *path);
 406
 407 const char * pure_func prefix_name(int);
 408
 409 /*
 410  * Wrappers around fopen()... for future change to a dedicated structure
 411  */
 412 enum file_flags {
 413     NF_BINARY   = 0x00000000,   /* Binary file (default) */
 414     NF_TEXT     = 0x00000001,   /* Text file */
 415     NF_NONFATAL = 0x00000000,   /* Don't die on open failure (default) */
 416     NF_FATAL    = 0x00000002,   /* Die on open failure */
 417     NF_FORMAP   = 0x00000004    /* Intended to use nasm_map_file() */
 418 };
 419
 420 FILE *nasm_open_read(const char *filename, enum file_flags flags);
 421 FILE *nasm_open_write(const char *filename, enum file_flags flags);
 422
 423 /* Probe for existence of a file */
 424 bool nasm_file_exists(const char *filename);
 425
 426 #define ZERO_BUF_SIZE 65536     /* Default value */
 427 #if defined(BUFSIZ) && (BUFSIZ > ZERO_BUF_SIZE)
 428 # undef ZERO_BUF_SIZE
 429 # define ZERO_BUF_SIZE BUFSIZ
 430 #endif
 431 extern const uint8_t zero_buffer[ZERO_BUF_SIZE];
 432
 433 /* Missing fseeko/ftello */
 434 #ifndef HAVE_FSEEKO
 435 # undef off_t                   /* Just in case it is a macro */
 436 # ifdef HAVE__FSEEKI64
 437 #  define fseeko _fseeki64
 438 #  define ftello _ftelli64
 439 #  define off_t  int64_t
 440 # else
 441 #  define fseeko fseek
 442 #  define ftello ftell
 443 #  define off_t  long
 444 # endif
 445 #endif
 446
 447 const void *nasm_map_file(FILE *fp, off_t start, off_t len);
 448 void nasm_unmap_file(const void *p, size_t len);
 449 off_t nasm_file_size(FILE *f);
 450 off_t nasm_file_size_by_path(const char *pathname);
 451 bool nasm_file_time(time_t *t, const char *pathname);
 452 void fwritezero(off_t bytes, FILE *fp);
 453
 454 static inline bool const_func overflow_general(int64_t value, int bytes)
 455 {
 456     int sbit;
 457     int64_t vmax, vmin;
 458
 459     if (bytes >= 8)
 460         return false;
 461
 462     sbit = (bytes << 3) - 1;
 463     vmax =  ((int64_t)2 << sbit) - 1;
 464     vmin = -((int64_t)1 << sbit);
 465
 466     return value < vmin || value > vmax;
 467 }
 468
 469 static inline bool const_func overflow_signed(int64_t value, int bytes)
 470 {
 471     int sbit;
 472     int64_t vmax, vmin;
 473
 474     if (bytes >= 8)
 475         return false;
 476
 477     sbit = (bytes << 3) - 1;
 478     vmax =  ((int64_t)1 << sbit) - 1;
 479     vmin = -((int64_t)1 << sbit);
 480
 481     return value < vmin || value > vmax;
 482 }
 483
 484 static inline bool const_func overflow_unsigned(int64_t value, int bytes)
 485 {
 486     int sbit;
 487     int64_t vmax, vmin;
 488
 489     if (bytes >= 8)
 490         return false;
 491
 492     sbit = (bytes << 3) - 1;
 493     vmax = ((int64_t)2 << sbit) - 1;
 494     vmin = 0;
 495
 496     return value < vmin || value > vmax;
 497 }
 498
 499 static inline int64_t const_func signed_bits(int64_t value, int bits)
 500 {
 501     if (bits < 64) {
 502         value &= ((int64_t)1 << bits) - 1;
 503         if (value & (int64_t)1 << (bits - 1))
 504             value |= (int64_t)((uint64_t)-1 << bits);
 505     }
 506     return value;
 507 }
 508
 509 /* check if value is power of 2 */
 510 #define is_power2(v)   ((v) && ((v) & ((v) - 1)) == 0)
 511
 512 /*
 513  * floor(log2(v))
 514  */
 515 int const_func ilog2_32(uint32_t v);
 516 int const_func ilog2_64(uint64_t v);
 517
 518 /*
 519  * v == 0 ? 0 : is_power2(x) ? ilog2_X(v) : -1
 520  */
 521 int const_func alignlog2_32(uint32_t v);
 522 int const_func alignlog2_64(uint64_t v);
 523
 524 #endif