include/nasmlib.h

   1 /* ----------------------------------------------------------------------- *
   2  *
   3  *   Copyright 1996-2018 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 #include "bytesex.h"
  43
  44 #include <stdio.h>
  45 #include <string.h>
  46 #ifdef HAVE_STRINGS_H
  47 # include <strings.h>
  48 #endif
  49
  50 /*
  51  * Wrappers around malloc, realloc, free and a few more. nasm_malloc
  52  * will fatal-error and die rather than return NULL; nasm_realloc will
  53  * do likewise, and will also guarantee to work right on being passed
  54  * a NULL pointer; nasm_free will do nothing if it is passed a NULL
  55  * pointer.
  56  */
  57 void * safe_malloc(1) nasm_malloc(size_t);
  58 void * safe_malloc(1) nasm_zalloc(size_t);
  59 void * safe_malloc2(1,2) nasm_calloc(size_t, size_t);
  60 void * safe_realloc(2) nasm_realloc(void *, size_t);
  61 void nasm_free(void *);
  62 char * safe_alloc nasm_strdup(const char *);
  63 char * safe_alloc nasm_strndup(const char *, size_t);
  64 char * safe_alloc nasm_strcat(const char *one, const char *two);
  65 char * safe_alloc end_with_null nasm_strcatn(const char *one, ...);
  66
  67 /*
  68  * nasm_[v]asprintf() are variants of the semi-standard [v]asprintf()
  69  * functions, except that we return the pointer instead of a count.
  70  * The size of the string (including the final NUL!) is available
  71  * by calling nasm_aprintf_size() afterwards.
  72  *
  73  * nasm_[v]axprintf() are similar, but allocates a user-defined amount
  74  * of storage before the string, and returns a pointer to the
  75  * allocated buffer.
  76  */
  77 char * safe_alloc printf_func(1, 2) nasm_asprintf(const char *fmt, ...);
  78 char * safe_alloc nasm_vasprintf(const char *fmt, va_list ap);
  79 void * safe_alloc printf_func(2, 3) nasm_axprintf(size_t extra, const char *fmt, ...);
  80 void * safe_alloc nasm_vaxprintf(size_t extra, const char *fmt, va_list ap);
  81
  82 extern size_t _nasm_aprintf_size;
  83 static inline size_t nasm_aprintf_size(void)
  84 {
  85     return _nasm_aprintf_size;
  86 }
  87
  88 /* Assert the argument is a pointer without evaluating it */
  89 #define nasm_assert_pointer(p) ((void)sizeof(*(p)))
  90
  91 #define nasm_new(p) ((p) = nasm_zalloc(sizeof(*(p))))
  92 #define nasm_newn(p,n) ((p) = nasm_calloc(sizeof(*(p)),(n)))
  93 /*
  94  * This is broken on platforms where there are pointers which don't
  95  * match void * in their internal layout.  It unfortunately also
  96  * loses any "const" part of the argument, although hopefully the
  97  * compiler will warn in that case.
  98  */
  99 #define nasm_delete(p)                                          \
 100     do {                                                        \
 101         void **_pp = (void **)&(p);                             \
 102         nasm_assert_pointer(p);                                 \
 103         nasm_free(*_pp);                                        \
 104         *_pp = NULL;                                            \
 105     } while (0)
 106 #define nasm_zero(x) (memset(&(x), 0, sizeof(x)))
 107 #define nasm_zeron(p,n) (memset((p), 0, (n)*sizeof(*(p))))
 108
 109 /*
 110  * Wrappers around fread()/fwrite() which fatal-errors on failure.
 111  * For fread(), only use this if EOF is supposed to be a fatal error!
 112  */
 113 void nasm_read(void *, size_t, FILE *);
 114 void nasm_write(const void *, size_t, FILE *);
 115
 116 /*
 117  * NASM failure at build time if the argument is false
 118  */
 119 #ifdef static_assert
 120 # define nasm_static_assert(x) static_assert((x), #x)
 121 #elif defined(HAVE_FUNC_ATTRIBUTE_ERROR) && defined(__OPTIMIZE__)
 122 # define nasm_static_assert(x)                                          \
 123     do {                                                                \
 124         if (!(x)) {                                                     \
 125             extern void __attribute__((error("assertion " #x " failed")))   \
 126                 _nasm_static_fail(void);                                \
 127             _nasm_static_fail();                                        \
 128         }                                                               \
 129     } while (0)
 130 #else
 131 /* See http://www.drdobbs.com/compile-time-assertions/184401873 */
 132 # define nasm_static_assert(x) \
 133     do { enum { _static_assert_failed = 1/(!!(x)) }; } while (0)
 134 #endif
 135
 136 /*
 137  * conditional static assert, if we know it is possible to determine
 138  * the assert value at compile time. Since if_constant triggers
 139  * pedantic warnings on gcc, turn them off explicitly around this code.
 140  */
 141 #ifdef static_assert
 142 # define nasm_try_static_assert(x)                                      \
 143     do {                                                                \
 144         not_pedantic_start                                              \
 145         static_assert(if_constant(x, true), #x);                        \
 146         not_pedantic_end                                                \
 147     } while (0)
 148 #elif defined(HAVE_FUNC_ATTRIBUTE_ERROR) && defined(__OPTIMIZE__)
 149 # define nasm_try_static_assert(x)                                      \
 150     do {                                                                \
 151         if (!if_constant(x, true)) {                                    \
 152             extern void __attribute__((error("assertion " #x " failed"))) \
 153                 _nasm_static_fail(void);                                \
 154             _nasm_static_fail();                                        \
 155         }                                                               \
 156     } while (0)
 157 #else
 158 # define nasm_try_static_assert(x) ((void)0)
 159 #endif
 160
 161 /*
 162  * NASM assert failure
 163  */
 164 fatal_func nasm_assert_failed(const char *, int, const char *);
 165 #define nasm_assert(x)                                          \
 166     do {                                                        \
 167         nasm_try_static_assert(x);                              \
 168         if (unlikely(!(x)))                                     \
 169             nasm_assert_failed(__FILE__,__LINE__,#x);           \
 170     } while (0)
 171
 172 /* Utility function to generate a string for an invalid enum */
 173 const char *invalid_enum_str(int);
 174
 175 /*
 176  * ANSI doesn't guarantee the presence of `stricmp' or
 177  * `strcasecmp'.
 178  */
 179 #if defined(HAVE_STRCASECMP)
 180 #define nasm_stricmp strcasecmp
 181 #elif defined(HAVE_STRICMP)
 182 #define nasm_stricmp stricmp
 183 #else
 184 int pure_func nasm_stricmp(const char *, const char *);
 185 #endif
 186
 187 #if defined(HAVE_STRNCASECMP)
 188 #define nasm_strnicmp strncasecmp
 189 #elif defined(HAVE_STRNICMP)
 190 #define nasm_strnicmp strnicmp
 191 #else
 192 int pure_func nasm_strnicmp(const char *, const char *, size_t);
 193 #endif
 194
 195 int pure_func nasm_memicmp(const char *, const char *, size_t);
 196
 197 #if defined(HAVE_STRSEP)
 198 #define nasm_strsep strsep
 199 #else
 200 char *nasm_strsep(char **stringp, const char *delim);
 201 #endif
 202
 203 #ifndef HAVE_DECL_STRNLEN
 204 size_t pure_func strnlen(const char *, size_t);
 205 #endif
 206
 207 /* This returns the numeric value of a given 'digit'. */
 208 #define numvalue(c)         ((c) >= 'a' ? (c) - 'a' + 10 : (c) >= 'A' ? (c) - 'A' + 10 : (c) - '0')
 209
 210 /*
 211  * Convert a string into a number, using NASM number rules. Sets
 212  * `*error' to true if an error occurs, and false otherwise.
 213  */
 214 int64_t readnum(const char *str, bool *error);
 215
 216 /*
 217  * Convert a character constant into a number. Sets
 218  * `*warn' to true if an overflow occurs, and false otherwise.
 219  * str points to and length covers the middle of the string,
 220  * without the quotes.
 221  */
 222 int64_t readstrnum(char *str, int length, bool *warn);
 223
 224 /*
 225  * seg_alloc: allocate a hitherto unused segment number.
 226  */
 227 int32_t seg_alloc(void);
 228
 229 /*
 230  * Add/replace or remove an extension to the end of a filename
 231  */
 232 const char *filename_set_extension(const char *inname, const char *extension);
 233
 234 /*
 235  * Utility macros...
 236  *
 237  * This is a useful #define which I keep meaning to use more often:
 238  * the number of elements of a statically defined array.
 239  */
 240 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
 241
 242 /*
 243  * List handling
 244  *
 245  *  list_for_each - regular iterator over list
 246  *  list_for_each_safe - the same but safe against list items removal
 247  *  list_last - find the last element in a list
 248  */
 249 #define list_for_each(pos, head)                        \
 250     for (pos = head; pos; pos = pos->next)
 251 #define list_for_each_safe(pos, n, head)                \
 252     for (pos = head, n = (pos ? pos->next : NULL); pos; \
 253         pos = n, n = (n ? n->next : NULL))
 254 #define list_last(pos, head)                            \
 255     for (pos = head; pos && pos->next; pos = pos->next) \
 256         ;
 257 #define list_reverse(head, prev, next)                  \
 258     do {                                                \
 259         if (!head || !head->next)                       \
 260             break;                                      \
 261         prev = NULL;                                    \
 262         while (head) {                                  \
 263             next = head->next;                          \
 264             head->next = prev;                          \
 265             prev = head;                                \
 266             head = next;                                \
 267         }                                               \
 268         head = prev;                                    \
 269     } while (0)
 270
 271 /*
 272  * Power of 2 align helpers
 273  */
 274 #undef ALIGN_MASK               /* Some BSD flavors define these in system headers */
 275 #undef ALIGN
 276 #define ALIGN_MASK(v, mask)     (((v) + (mask)) & ~(mask))
 277 #define ALIGN(v, a)             ALIGN_MASK(v, (a) - 1)
 278 #define IS_ALIGNED(v, a)        (((v) & ((a) - 1)) == 0)
 279
 280 /*
 281  * Routines to write littleendian data to a file
 282  */
 283 #define fwriteint8_t(d,f) putc(d,f)
 284 void fwriteint16_t(uint16_t data, FILE * fp);
 285 void fwriteint32_t(uint32_t data, FILE * fp);
 286 void fwriteint64_t(uint64_t data, FILE * fp);
 287 void fwriteaddr(uint64_t data, int size, FILE * fp);
 288
 289 /*
 290  * Binary search routine. Returns index into `array' of an entry
 291  * matching `string', or <0 if no match. `array' is taken to
 292  * contain `size' elements.
 293  *
 294  * bsi() is case sensitive, bsii() is case insensitive.
 295  */
 296 int bsi(const char *string, const char **array, int size);
 297 int bsii(const char *string, const char **array, int size);
 298
 299 /*
 300  * Convenient string processing helper routines
 301  */
 302 char *nasm_skip_spaces(const char *p);
 303 char *nasm_skip_word(const char *p);
 304 char *nasm_zap_spaces_fwd(char *p);
 305 char *nasm_zap_spaces_rev(char *p);
 306 char *nasm_trim_spaces(char *p);
 307 char *nasm_get_word(char *p, char **tail);
 308 char *nasm_opt_val(char *p, char **opt, char **val);
 309
 310 /*
 311  * Converts a relative pathname rel_path into an absolute path name.
 312  *
 313  * The buffer returned must be freed by the caller
 314  */
 315 char * safe_alloc nasm_realpath(const char *rel_path);
 316
 317 /*
 318  * Path-splitting and merging functions
 319  */
 320 char * safe_alloc nasm_dirname(const char *path);
 321 char * safe_alloc nasm_basename(const char *path);
 322 char * safe_alloc nasm_catfile(const char *dir, const char *path);
 323
 324 const char * pure_func prefix_name(int);
 325
 326 /*
 327  * Wrappers around fopen()... for future change to a dedicated structure
 328  */
 329 enum file_flags {
 330     NF_BINARY   = 0x00000000,   /* Binary file (default) */
 331     NF_TEXT     = 0x00000001,   /* Text file */
 332     NF_NONFATAL = 0x00000000,   /* Don't die on open failure (default) */
 333     NF_FATAL    = 0x00000002,   /* Die on open failure */
 334     NF_FORMAP   = 0x00000004    /* Intended to use nasm_map_file() */
 335 };
 336
 337 FILE *nasm_open_read(const char *filename, enum file_flags flags);
 338 FILE *nasm_open_write(const char *filename, enum file_flags flags);
 339
 340 /* Probe for existence of a file */
 341 bool nasm_file_exists(const char *filename);
 342
 343 #define ZERO_BUF_SIZE 65536     /* Default value */
 344 #if defined(BUFSIZ) && (BUFSIZ > ZERO_BUF_SIZE)
 345 # undef ZERO_BUF_SIZE
 346 # define ZERO_BUF_SIZE BUFSIZ
 347 #endif
 348 extern const uint8_t zero_buffer[ZERO_BUF_SIZE];
 349
 350 /* Missing fseeko/ftello */
 351 #ifndef HAVE_FSEEKO
 352 # undef off_t                   /* Just in case it is a macro */
 353 # ifdef HAVE__FSEEKI64
 354 #  define fseeko _fseeki64
 355 #  define ftello _ftelli64
 356 #  define off_t  int64_t
 357 # else
 358 #  define fseeko fseek
 359 #  define ftello ftell
 360 #  define off_t  long
 361 # endif
 362 #endif
 363
 364 const void *nasm_map_file(FILE *fp, off_t start, off_t len);
 365 void nasm_unmap_file(const void *p, size_t len);
 366 off_t nasm_file_size(FILE *f);
 367 off_t nasm_file_size_by_path(const char *pathname);
 368 bool nasm_file_time(time_t *t, const char *pathname);
 369 void fwritezero(off_t bytes, FILE *fp);
 370
 371 static inline bool const_func overflow_general(int64_t value, int bytes)
 372 {
 373     int sbit;
 374     int64_t vmax, vmin;
 375
 376     if (bytes >= 8)
 377         return false;
 378
 379     sbit = (bytes << 3) - 1;
 380     vmax =  ((int64_t)2 << sbit) - 1;
 381     vmin = -((int64_t)2 << sbit);
 382
 383     return value < vmin || value > vmax;
 384 }
 385
 386 static inline bool const_func overflow_signed(int64_t value, int bytes)
 387 {
 388     int sbit;
 389     int64_t vmax, vmin;
 390
 391     if (bytes >= 8)
 392         return false;
 393
 394     sbit = (bytes << 3) - 1;
 395     vmax =  ((int64_t)1 << sbit) - 1;
 396     vmin = -((int64_t)1 << sbit);
 397
 398     return value < vmin || value > vmax;
 399 }
 400
 401 static inline bool const_func overflow_unsigned(int64_t value, int bytes)
 402 {
 403     int sbit;
 404     int64_t vmax, vmin;
 405
 406     if (bytes >= 8)
 407         return false;
 408
 409     sbit = (bytes << 3) - 1;
 410     vmax = ((int64_t)2 << sbit) - 1;
 411     vmin = 0;
 412
 413     return value < vmin || value > vmax;
 414 }
 415
 416 static inline int64_t const_func signed_bits(int64_t value, int bits)
 417 {
 418     if (bits < 64) {
 419         value &= ((int64_t)1 << bits) - 1;
 420         if (value & (int64_t)1 << (bits - 1))
 421             value |= (int64_t)((uint64_t)-1 << bits);
 422     }
 423     return value;
 424 }
 425
 426 /* check if value is power of 2 */
 427 #define is_power2(v)   ((v) && ((v) & ((v) - 1)) == 0)
 428
 429 #endif