/* SPDX-License-Identifier: BSD-2-Clause */ /* Copyright 1996-2025 The NASM Authors - All Rights Reserved */ /* * nasmlib.h header file for nasmlib.c */ #ifndef NASM_NASMLIB_H #define NASM_NASMLIB_H #include "compiler.h" #include "bytesex.h" /* * Useful construct for private values */ union intorptr { int64_t i; uint64_t u; size_t s; void *p; const void *cp; uintptr_t up; }; typedef union intorptr intorptr; /* * Handy macro to use as the base of shifts */ #define ONE ((uintmax_t)1) /* * Handy macros for defining and accessing enums of bitfields; * provides a set of standard-named parameters for each field. * * mk_field_mask() is indended to be used for non-contiguous fields. */ #define mk_field_mask(name,pos,width,basemask) \ name ## _POS = (pos), \ name ## _WIDTH = (width), \ name ## _BASEMASK = (basemask), \ name ## _MASK = name ## _BASEMASK << name ## _POS, \ name = name ## _MASK #define mk_field(name,pos,width) \ mk_field_mask(name,pos,width, \ (1 << name ## _WIDTH)-1) /* * Cast a value to a suitable type to represent the encoded * (post-shift) and extracted (pre-shift) values, respectively. */ #ifdef HAVE_TYPEOF # define fieldenc_cast(x,y) ((typeof(x ## _MASK))(y)) # define fieldval_cast(x,y) ((typeof(x ## _BASEMASK))(y)) #else /* * Using int here matches the strict ISO C before C23 which only allows * an enum to be in the range of "int". This also means that these macros * are only usable for bitfields up to 32 bits wide, which is extremely * unfortunate, but covers most of all the NASM use cases. * * The (int) should at least give a warning on overflow. */ # define fieldenc_cast(x,y) ((int)(y)) # define fieldval_cast(x,y) (y) #endif /* * Macros to get/set bitfield values (the set macro returns the * updated value, it does not change the input.) * * The fieldenc() macro produces the masked and shifted value * corresponding to a base value; it is equivalent to * setfield(field,0,val). */ #define getfield(field,from) \ fieldval_cast(field, \ (((from) >> field ## _POS) & \ field ## _BASEMASK)) #define fieldval(field,val) \ (((val) & fieldenc_cast(field,field ## _BASEMASK)) \ << field ## _POS) #define setfield(field,from,val) \ (((from) & ~(field ## _MASK)) + fieldval(field,val)) /* * Wrappers around malloc, realloc, free and a few more. nasm_malloc * will fatal-error and die rather than return NULL; nasm_realloc will * do likewise, and will also guarantee to work right on being passed * a NULL pointer; nasm_free will do nothing if it is passed a NULL * pointer. */ void * safe_malloc(1) nasm_malloc(size_t); void * safe_malloc(1) nasm_zalloc(size_t); void * safe_malloc2(1,2) nasm_calloc(size_t, size_t); void * safe_realloc(2) nasm_realloc(void *, size_t); void nasm_free(void *); char * safe_alloc nasm_strdup(const char *); char * safe_alloc nasm_strndup(const char *, size_t); char * safe_alloc nasm_strcat(const char *one, const char *two); char * safe_alloc end_with_null nasm_strcatn(const char *one, ...); /* * nasm_[v]asprintf() are variants of the semi-standard [v]asprintf() * functions, except that we return the pointer instead of a count. * The size of the string (including the final NUL!) is available * by calling nasm_last_string_size() afterwards. * * nasm_[v]axprintf() are similar, but allocates a user-defined amount * of storage before the string, and returns a pointer to the * allocated buffer. The value of nasm_last_string_size() does *not* include * this additional storage. */ char * safe_alloc printf_func(1, 2) nasm_asprintf(const char *fmt, ...); char * safe_alloc vprintf_func(1) nasm_vasprintf(const char *fmt, va_list ap); void * safe_alloc printf_func(2, 3) nasm_axprintf(size_t extra, const char *fmt, ...); void * safe_alloc vprintf_func(2) nasm_vaxprintf(size_t extra, const char *fmt, va_list ap); /* * nasm_last_string_len() returns the length of the last string allocated * by [v]asprintf, nasm_strdup, nasm_strcat, or nasm_strcatn. * * nasm_last_string_size() returns the equivalent size including the * final NUL. */ static inline size_t nasm_last_string_len(void) { extern size_t _nasm_last_string_size; return _nasm_last_string_size - 1; } static inline size_t nasm_last_string_size(void) { extern size_t _nasm_last_string_size; return _nasm_last_string_size; } /* Statically assert the argument is a pointer without evaluating it */ #define nasm_assert_pointer(p) ((void)sizeof(*(p))) #define nasm_new(p) ((p) = nasm_zalloc(sizeof(*(p)))) #define nasm_newn(p,n) ((p) = nasm_calloc((n), sizeof(*(p)))) /* * This is broken on platforms where there are pointers which don't * match void * in their internal layout. It unfortunately also * loses any "const" part of the argument, although hopefully the * compiler will warn in that case. */ #define nasm_delete(p) \ do { \ void **_pp = (void **)&(p); \ nasm_assert_pointer(p); \ nasm_free(*_pp); \ *_pp = NULL; \ } while (0) #define nasm_zero(x) (memset(&(x), 0, sizeof(x))) #define nasm_zeron(p,n) (memset((p), 0, (n)*sizeof(*(p)))) /* * Wrappers around fread()/fwrite() which fatal-errors on failure. * For fread(), only use this if EOF is supposed to be a fatal error! */ void nasm_read(void *, size_t, FILE *); void nasm_write(const void *, size_t, FILE *); /* * NASM failure at build time if the argument is false */ #ifdef static_assert # define nasm_static_assert(x) static_assert((x), #x) #elif defined(HAVE_FUNC_ATTRIBUTE_ERROR) && defined(__OPTIMIZE__) # define nasm_static_assert(x) \ do { \ if (!(x)) { \ extern void __attribute__((error("assertion " #x " failed"))) \ _nasm_static_fail(void); \ _nasm_static_fail(); \ } \ } while (0) #else /* See http://www.drdobbs.com/compile-time-assertions/184401873 */ # define nasm_static_assert(x) \ do { enum { _static_assert_failed = 1/(!!(x)) }; } while (0) #endif /* * conditional static assert, if we know it is possible to determine * the assert value at compile time. Since if_constant triggers * pedantic warnings on gcc, turn them off explicitly around this code. */ #ifdef static_assert # define nasm_try_static_assert(x) \ do { \ not_pedantic_start \ static_assert(if_constant(x, true), #x); \ not_pedantic_end \ } while (0) #elif defined(HAVE_FUNC_ATTRIBUTE_ERROR) && defined(__OPTIMIZE__) # define nasm_try_static_assert(x) \ do { \ if (!if_constant(x, true)) { \ extern void __attribute__((error("assertion " #x " failed"))) \ _nasm_static_fail(void); \ _nasm_static_fail(); \ } \ } while (0) #else # define nasm_try_static_assert(x) ((void)0) #endif /* * NASM assert failure */ fatal_func nasm_assert_failed(const char *msg, const char *func, const char *file, int line); /* Plain assert, gives the source location as an error message */ #define nasm_assert(x) \ do { \ nasm_try_static_assert(x); \ if (unlikely(!(x))) \ nasm_assert_failed(#x,NASM_FUNC,__FILE__,__LINE__); \ } while (0) /* Assert with custom message */ #define nasm_assert_msg(x,m) \ do { \ nasm_try_static_assert(x); \ if (unlikely(!(x))) \ nasm_panic("%s", m); \ } while (0) /* Utility function to generate a string for an invalid enum */ const char *invalid_enum_str(int); /* * ANSI doesn't guarantee the presence of `stricmp' or * `strcasecmp'. */ #if defined(HAVE_STRCASECMP) #define nasm_stricmp strcasecmp #elif defined(HAVE_STRICMP) #define nasm_stricmp stricmp #else int pure_func nasm_stricmp(const char *, const char *); #endif #if defined(HAVE_STRNCASECMP) #define nasm_strnicmp strncasecmp #elif defined(HAVE_STRNICMP) #define nasm_strnicmp strnicmp #else int pure_func nasm_strnicmp(const char *, const char *, size_t); #endif int pure_func nasm_memicmp(const char *, const char *, size_t); #if defined(HAVE_STRSEP) #define nasm_strsep strsep #else char *nasm_strsep(char **stringp, const char *delim); #endif #ifndef HAVE_DECL_STRNLEN size_t pure_func strnlen(const char *, size_t); #endif /* This returns the numeric value of a given 'digit'; no check for validity */ static inline unsigned int numvalue(unsigned char c) { c |= 0x20; return c >= 'a' ? c - 'a' + 10 : c - '0'; } /* * Convert a string into a number, using NASM number rules. Sets * `*error' to true if an error occurs, and false otherwise. */ int64_t readnum(const char *str, bool *error); /* * Warn for the use of $ as a hexadecimal prefix */ void warn_dollar_hex(void); /* * Get the numeric base corresponding to a character */ static inline unsigned int radix_letter(char c) { switch (c) { case 'b': case 'B': case 'y': case 'Y': return 2; /* Binary */ case 'o': case 'O': case 'q': case 'Q': return 8; /* Octal */ case 'h': case 'H': case 'x': case 'X': return 16; /* Hexadecimal */ case 'd': case 'D': case 't': case 'T': return 10; /* Decimal */ default: return 0; /* Not a known radix letter */ } } /* * Convert a character constant into a number. Sets * `*warn' to true if an overflow occurs, and false otherwise. * str points to and length covers the middle of the string, * without the quotes. */ int64_t readstrnum(char *str, int length, bool *warn); /* * Produce an unsigned integer string from a number with a specified * base, digits and signedness */ #define NUMSTR_MAXBASE 64 int numstr(char *buf, size_t buflen, uint64_t n, int digits, unsigned int base, bool ucase); extern const char * const nasmlib_digit_chars[2]; static inline const char *nasm_digit_chars(bool ucase) { return nasmlib_digit_chars[ucase]; } /* * seg_alloc: allocate a hitherto unused segment number. */ int32_t seg_alloc(void); /* * Add/replace or remove an extension to the end of a filename */ const char *filename_set_extension(const char *inname, const char *extension); /* * Utility macros... * * This is a useful #define which I keep meaning to use more often: * the number of elements of a statically defined array. */ #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0])) #define ARRAY_END(arr) (&(arr)[ARRAY_SIZE(arr)]) #define array_for_each(var,arr) \ for ((var) = (arr); (var) < ARRAY_END(arr); (var)++) /* * List handling * * list_for_each - regular iterator over list * list_for_each_safe - the same but safe against list items removal * list_last - find the last element in a list * list_reverse - reverse the order of a list * * Arguments named with _ + single letter should be temp variables * of the appropriate pointer type. */ #define list_for_each(pos, head) \ for (pos = head; pos; pos = pos->next) #define list_for_each_safe(pos, _n, head) \ for (pos = head, _n = (pos ? pos->next : NULL); pos; \ pos = _n, _n = (_n ? _n->next : NULL)) #define list_last(pos, head) \ do { \ for (pos = head; pos && pos->next; pos = pos->next) \ ; \ } while (0) #define list_reverse(head) \ do { \ void *_p, *_n; \ if (!head || !head->next) \ break; \ _p = NULL; \ while (head) { \ _n = head->next; \ head->next = _p; \ _p = head; \ head = _n; \ } \ head = _p; \ } while (0) /* * Power of 2 align helpers */ #undef ALIGN_MASK /* Some BSD flavors define these in system headers */ #undef ALIGN #define ALIGN_MASK(v, mask) (((v) + (mask)) & ~(mask)) #define ALIGN(v, a) ALIGN_MASK(v, (a) - 1) #define IS_ALIGNED(v, a) (((v) & ((a) - 1)) == 0) /* * Routines to write littleendian data to a file */ #define fwriteint8_t(d,f) putc(d,f) void fwriteint16_t(uint16_t data, FILE * fp); void fwriteint32_t(uint32_t data, FILE * fp); void fwriteint64_t(uint64_t data, FILE * fp); void fwriteaddr(uint64_t data, int size, FILE * fp); /* * Binary search routine. Returns index into `array' of an entry * matching `string', or <0 if no match. `array' is taken to * contain `size' elements. * * bsi() is case sensitive, bsii() is case insensitive. */ int pure_func bsi(const char *string, const char **array, int size); int pure_func bsii(const char *string, const char **array, int size); /* * Convenient string processing helper routines */ char * pure_func nasm_skip_spaces(const char *p); char * pure_func nasm_skip_word(const char *p); char *nasm_zap_spaces_fwd(char *p); char *nasm_zap_spaces_rev(char *p); char *nasm_trim_spaces(char *p); char *nasm_get_word(char *p, char **tail); char *nasm_opt_val(char *p, char **opt, char **val); /* * Converts a relative pathname rel_path into an absolute path name. * * The buffer returned must be freed by the caller */ char * safe_alloc nasm_realpath(const char *rel_path); /* * Path-splitting and merging functions */ char * safe_alloc nasm_dirname(const char *path); char * safe_alloc nasm_basename(const char *path); char * safe_alloc nasm_catfile(const char *dir, const char *path); /* * Various tokens to readable strings, with limit checking */ const char * const_func register_name(int); const char * const_func prefix_name(int); bool const_func is_hint_nop(uint64_t); /* * Wrappers around fopen()... for future change to a dedicated structure */ enum file_flags { NF_BINARY = 0x00000000, /* Binary file (default) */ NF_TEXT = 0x00000001, /* Text file */ NF_NONFATAL = 0x00000000, /* Don't die on open failure (default) */ NF_FATAL = 0x00000002, /* Die on open failure */ NF_FORMAP = 0x00000004, /* Intended to use nasm_map_file() */ NF_IONBF = 0x00000010, /* Force unbuffered stdio */ NF_IOLBF = 0x00000020, /* Force line buffered stdio */ NF_IOFBF = 0000000030 /* Force fully buffered stdio */ }; #define NF_BUF_MASK 0x30 FILE *nasm_open_read(const char *filename, enum file_flags flags); FILE *nasm_open_write(const char *filename, enum file_flags flags); void nasm_set_binary_mode(FILE *f); /* Probe for existence of a file */ bool nasm_file_exists(const char *filename); #define ZERO_BUF_SIZE 65536 /* Default value */ #if defined(BUFSIZ) && (BUFSIZ > ZERO_BUF_SIZE) # undef ZERO_BUF_SIZE # define ZERO_BUF_SIZE BUFSIZ #endif extern const uint8_t zero_buffer[ZERO_BUF_SIZE]; /* Missing fseeko/ftello */ #ifndef HAVE_FSEEKO # undef off_t /* Just in case it is a macro */ # ifdef HAVE__FSEEKI64 # define fseeko _fseeki64 # define ftello _ftelli64 # define off_t int64_t # else # define fseeko fseek # define ftello ftell # define off_t long # endif #endif const void *nasm_map_file(FILE *fp, off_t start, off_t len); void nasm_unmap_file(const void *p, size_t len); off_t nasm_file_size(FILE *f); off_t nasm_file_size_by_path(const char *pathname); bool nasm_file_time(time_t *t, const char *pathname); void fwritezero(off_t bytes, FILE *fp); /* Sign-extend a value to an arbitrary number of bits */ static inline int64_t const_func sext(int64_t value, unsigned int bits) { if (is_constant(bits)) { switch (bits) { case 8: return (int8_t)value; case 16: return (int16_t)value; case 32: return (int32_t)value; default: break; } } if (bits >= 64) return value; /* sext(foo,0) == sext(foo,1) */ bits = bits ? 64-bits : 63; return value << bits >> bits; } /* Zero-extend a value to an arbitrary number of bits */ static inline uint64_t const_func zext(uint64_t value, unsigned int bits) { if (is_constant(bits)) { switch (bits) { case 8: return (uint8_t)value; case 16: return (uint16_t)value; case 32: return (uint32_t)value; default: break; } } if (bits >= 64) return value; if (!bits) return 0; bits = 64-bits; return value << bits >> bits; } static inline bool const_func overflow_signed(int64_t value, unsigned int bytes) { return sext(value, bytes << 3) != value; } static inline bool const_func overflow_unsigned(uint64_t value, unsigned int bytes) { return zext(value, bytes << 3) != value; } /* This is very conservative, but otherwise things like ~0x80 break */ static inline bool const_func overflow_general(int64_t value, unsigned int bytes) { return overflow_unsigned(value, bytes) && overflow_unsigned(-value, bytes); } /* check if value is power of 2 */ #define is_power2(v) ((v) && ((v) & ((v) - 1)) == 0) /* try to get the system stack size */ extern size_t nasm_get_stack_size_limit(void); #endif