general.h

   1 /* general.h -- defines that everybody likes to use. */
   2
   3 /* Copyright (C) 1993-2023 Free Software Foundation, Inc.
   4
   5    This file is part of GNU Bash, the Bourne Again SHell.
   6
   7    Bash is free software: you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation, either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    Bash is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with Bash.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #if !defined (_GENERAL_H_)
  22 #define _GENERAL_H_
  23
  24 #include "stdc.h"
  25
  26 #include "bashtypes.h"
  27 #include "chartypes.h"
  28
  29 #if defined (HAVE_SYS_RESOURCE_H) && defined (RLIMTYPE)
  30 #  if defined (HAVE_SYS_TIME_H)
  31 #    include <sys/time.h>
  32 #  endif
  33 #  include <sys/resource.h>
  34 #endif
  35
  36 #if defined (HAVE_STRING_H)
  37 #  include <string.h>
  38 #else
  39 #  include <strings.h>
  40 #endif /* !HAVE_STRING_H */
  41
  42 #if defined (HAVE_LIMITS_H)
  43 #  include <limits.h>
  44 #endif
  45
  46 #include "xmalloc.h"
  47
  48 /* Hardly used anymore */
  49 #define pointer_to_int(x)       (int)((char *)x - (char *)0)
  50
  51 #if !defined (strcpy) && (defined (HAVE_DECL_STRCPY) && !HAVE_DECL_STRCPY)
  52 extern char *strcpy (char *, const char *);
  53 #endif
  54
  55 #if !defined (savestring)
  56 #  define savestring(x) (char *)strcpy (xmalloc (1 + strlen (x)), (x))
  57 #endif
  58
  59 #ifndef member
  60 #  define member(c, s) ((c) ? ((char *)mbschr ((s), (c)) != (char *)NULL) : 0)
  61 #endif
  62
  63 #ifndef whitespace
  64 #define whitespace(c) (((c) == ' ') || ((c) == '\t'))
  65 #endif
  66
  67 #ifndef CHAR_MAX
  68 #  ifdef __CHAR_UNSIGNED__
  69 #    define CHAR_MAX    0xff
  70 #  else
  71 #    define CHAR_MAX    0x7f
  72 #  endif
  73 #endif
  74
  75 #ifndef CHAR_BIT
  76 #  define CHAR_BIT 8
  77 #endif
  78
  79 /* Nonzero if the integer type T is signed.  */
  80 #define TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
  81
  82 /* The width in bits of the integer type or expression T.
  83    Padding bits are not supported; this is checked at compile-time below.  */
  84 #define TYPE_WIDTH(t) (sizeof (t) * CHAR_BIT)
  85
  86 /* Bound on length of the string representing an unsigned integer
  87    value representable in B bits.  log10 (2.0) < 146/485.  The
  88       smallest value of B where this bound is not tight is 2621.  */
  89 #define INT_BITS_STRLEN_BOUND(b) (((b) * 146 + 484) / 485)
  90
  91 /* Bound on length of the string representing an integer value of type T.
  92    Subtract one for the sign bit if T is signed;
  93    302 / 1000 is log10 (2) rounded up;
  94    add one for integer division truncation;
  95    add one more for a minus sign if t is signed.  */
  96 #define INT_STRLEN_BOUND(t) \
  97   ((TYPE_WIDTH (t) - TYPE_SIGNED (t)) * 302 / 1000 \
  98    + 1 + TYPE_SIGNED (t))
  99
 100 /* Updated version adapted from gnulib/intprops.h, not used right now.
 101    Changes the approximation of log10(2) from 302/1000 to 146/485. */
 102 #if 0
 103 #define INT_STRLEN_BOUND(t) \
 104   (INT_BITS_STRLEN_BOUND (TYPE_WIDTH (t) - TYPE_SIGNED (t)) + TYPE_SIGNED(t))
 105 #endif
 106
 107 /* Bound on buffer size needed to represent an integer type or expression T,
 108    including the terminating null.  */
 109 #define INT_BUFSIZE_BOUND(t) (INT_STRLEN_BOUND (t) + 1)
 110
 111 /* Define exactly what a legal shell identifier consists of. */
 112 #define legal_variable_starter(c) (ISALPHA(c) || (c == '_'))
 113 #define legal_variable_char(c)  (ISALNUM(c) || c == '_')
 114
 115 /* Definitions used in subst.c and by the `read' builtin for field
 116    splitting. */
 117 #define spctabnl(c)     ((c) == ' ' || (c) == '\t' || (c) == '\n')
 118
 119 /* All structs which contain a `next' field should have that field
 120    as the first field in the struct.  This means that functions
 121    can be written to handle the general case for linked lists. */
 122 typedef struct g_list {
 123   struct g_list *next;
 124 } GENERIC_LIST;
 125
 126 /* Here is a generic structure for associating character strings
 127    with integers.  It is used in the parser for shell tokenization. */
 128 typedef struct {
 129   char *word;
 130   int token;
 131 } STRING_INT_ALIST;
 132
 133 /* A macro to avoid making an unnecessary function call. */
 134 #define REVERSE_LIST(list, type) \
 135   ((list && list->next) ? (type)list_reverse ((GENERIC_LIST *)list) \
 136                         : (type)(list))
 137
 138 #if __GNUC__ > 1
 139 #  define FASTCOPY(s, d, n)  __builtin_memcpy ((d), (s), (n))
 140 #else /* !__GNUC__ */
 141 #  if !defined (HAVE_BCOPY)
 142 #    if !defined (HAVE_MEMMOVE)
 143 #      define FASTCOPY(s, d, n)  memcpy ((d), (s), (n))
 144 #    else
 145 #      define FASTCOPY(s, d, n)  memmove ((d), (s), (n))
 146 #    endif /* !HAVE_MEMMOVE */
 147 #  else /* HAVE_BCOPY */
 148 #    define FASTCOPY(s, d, n)  bcopy ((s), (d), (n))
 149 #  endif /* HAVE_BCOPY */
 150 #endif /* !__GNUC__ */
 151
 152 /* String comparisons that possibly save a function call each. */
 153 static inline int
 154 STREQ(const char *a, const char *b)
 155 {
 156   return ((a)[0] == (b)[0] && strcmp(a, b) == 0);
 157 }
 158
 159 static inline int
 160 STREQN(const char *a, const char *b, size_t n)
 161 {
 162   return ((n == 0) || ((a)[0] == (b)[0] && strncmp(a, b, n) == 0));
 163 }
 164
 165 /* More convenience definitions that possibly save system or libc calls. */
 166 #define STRLEN(s) (((s) && (s)[0]) ? ((s)[1] ? ((s)[2] ? strlen(s) : 2) : 1) : 0)
 167 #define FREE(s)  do { if (s) free (s); } while (0)
 168 #define MEMBER(c, s) (((c) && c == (s)[0] && !(s)[1]) || (member(c, s)))
 169
 170 /* A fairly hairy macro to check whether an allocated string has more room,
 171    and to resize it using xrealloc if it does not.
 172    STR is the string (char *)
 173    CIND is the current index into the string (int)
 174    ROOM is the amount of additional room we need in the string (int)
 175    CSIZE is the currently-allocated size of STR (int)
 176    SINCR is how much to increment CSIZE before calling xrealloc (int) */
 177
 178 #define RESIZE_MALLOCED_BUFFER(str, cind, room, csize, sincr) \
 179   do { \
 180     if ((cind) + (room) >= csize) \
 181       { \
 182         while ((cind) + (room) >= csize) \
 183           csize += (sincr); \
 184         str = xrealloc (str, csize); \
 185       } \
 186   } while (0)
 187
 188 #ifndef SH_FUNCTION_TYPEDEF
 189 #  define SH_FUNCTION_TYPEDEF
 190
 191 /* Shell function typedefs with prototypes */
 192 /* `Generic' function pointer typedefs */
 193
 194 typedef int sh_intfunc_t (int);
 195 typedef int sh_ivoidfunc_t (void);
 196 typedef int sh_icpfunc_t (char *);
 197 typedef int sh_icppfunc_t (char **);
 198 typedef int sh_iptrfunc_t (PTR_T);
 199
 200 typedef void sh_voidfunc_t (void);
 201 typedef void sh_vintfunc_t (int);
 202 typedef void sh_vcpfunc_t (char *);
 203 typedef void sh_vcppfunc_t (char **);
 204 typedef void sh_vptrfunc_t (PTR_T);
 205
 206 typedef int sh_wdesc_func_t (WORD_DESC *);
 207 typedef int sh_wlist_func_t (WORD_LIST *);
 208
 209 typedef int sh_glist_func_t (GENERIC_LIST *);
 210 typedef int sh_gcp_func_t (GENERIC_LIST *, char *);
 211
 212 typedef char *sh_string_func_t (char *);        /* like savestring, et al. */
 213
 214 typedef int sh_msg_func_t (const char *, ...);  /* printf(3)-like */
 215 typedef void sh_vmsg_func_t (const char *, ...);        /* printf(3)-like */
 216
 217 /* Specific function pointer typedefs.  Most of these could be done
 218    with #defines. */
 219 typedef void sh_sv_func_t (const char *);
 220 typedef void sh_free_func_t (PTR_T);    /* sh_vptrfunc_t */
 221 typedef void sh_resetsig_func_t (int);  /* sh_vintfunc_t */
 222
 223 typedef int sh_ignore_func_t (const char *);    /* sh_icpfunc_t */
 224
 225 typedef int sh_assign_func_t (const char *);
 226 typedef int sh_wassign_func_t (const WORD_DESC *, int);
 227
 228 typedef int sh_load_func_t (char *);
 229 typedef void sh_unload_func_t (char *);
 230
 231 typedef int sh_builtin_func_t (WORD_LIST *); /* sh_wlist_func_t */
 232
 233 #endif /* SH_FUNCTION_TYPEDEF */
 234
 235 #define NOW     getnow()
 236 #define GETTIME(tv)     gettimeofday(&(tv), NULL)
 237
 238 /* Some defines for calling file status functions. */
 239 #define FS_EXISTS         0x1
 240 #define FS_EXECABLE       0x2
 241 #define FS_EXEC_PREFERRED 0x4
 242 #define FS_EXEC_ONLY      0x8
 243 #define FS_DIRECTORY      0x10
 244 #define FS_NODIRS         0x20
 245 #define FS_READABLE       0x40
 246
 247 /* Default maximum for move_to_high_fd */
 248 #define HIGH_FD_MAX     256
 249
 250 /* The type of function passed as the fourth argument to qsort(3). */
 251 typedef int QSFUNC (const void *, const void *);
 252
 253 /* Some useful definitions for Unix pathnames.  Argument convention:
 254    x == string, c == character */
 255
 256 #if !defined (__CYGWIN__)
 257 #  define ABSPATH(x)    ((x)[0] == '/')
 258 #  define RELPATH(x)    ((x)[0] != '/')
 259 #else /* __CYGWIN__ */
 260 #  define ABSPATH(x)    (((x)[0] && ISALPHA((unsigned char)(x)[0]) && (x)[1] == ':') || ISDIRSEP((x)[0]))
 261 #  define RELPATH(x)    (ABSPATH(x) == 0)
 262 #endif /* __CYGWIN__ */
 263
 264 #define ROOTEDPATH(x)   (ABSPATH(x))
 265
 266 #define DIRSEP  '/'
 267 #if !defined (__CYGWIN__)
 268 #  define ISDIRSEP(c)   ((c) == '/')
 269 #else
 270 #  define ISDIRSEP(c)   ((c) == '/' || (c) == '\\')
 271 #endif /* __CYGWIN__ */
 272 #define PATHSEP(c)      (ISDIRSEP(c) || (c) == 0)
 273
 274 #define DOT_OR_DOTDOT(s)        (s[0] == '.' && (s[1] == 0 || (s[1] == '.' && s[2] == 0)))
 275
 276 #if defined (HANDLE_MULTIBYTE)
 277 #define WDOT_OR_DOTDOT(w)       (w[0] == L'.' && (w[1] == L'\0' || (w[1] == L'.' && w[2] == L'\0')))
 278 #endif
 279
 280 #if 0
 281 /* Declarations for functions defined in xmalloc.c */
 282 extern PTR_T xmalloc (size_t);
 283 extern PTR_T xrealloc (void *, size_t);
 284 extern void xfree (void *);
 285 #endif
 286
 287 /* Declarations for functions defined in general.c */
 288 extern void posix_initialize (int);
 289
 290 extern size_t num_posix_options (void);
 291 extern char *get_posix_options (char *);
 292 extern void set_posix_options (const char *);
 293
 294 extern void save_posix_options (void);
 295
 296 #if defined (RLIMTYPE)
 297 extern RLIMTYPE string_to_rlimtype (char *);
 298 extern void print_rlimtype (RLIMTYPE, int);
 299 #endif
 300
 301 extern int all_digits (const char *);
 302 extern int legal_number (const char *, intmax_t *);
 303 extern int legal_identifier (const char *);
 304 extern int importable_function_name (const char *, size_t);
 305 extern int exportable_function_name (const char *);
 306 extern int check_identifier (WORD_DESC *, int);
 307 extern int valid_nameref_value (const char *, int);
 308 extern int check_selfref (const char *, char *, int);
 309 extern int legal_alias_name (const char *, int);
 310 extern int valid_function_name (const char *, int);
 311 extern int valid_function_word (WORD_DESC *, int);
 312 extern int line_isblank (const char *);
 313 extern int assignment (const char *, int);
 314
 315 extern int sh_unset_nodelay_mode (int);
 316 extern int sh_setclexec (int);
 317 extern int sh_validfd (int);
 318 extern int fd_ispipe (int);
 319 extern void check_dev_tty (void);
 320 extern int move_to_high_fd (int, int, int);
 321 extern int check_binary_file (const char *, int);
 322
 323 #ifdef _POSIXSTAT_H_
 324 extern int same_file (const char *, const char *, struct stat *, struct stat *);
 325 #endif
 326
 327 extern int sh_openpipe (int *);
 328 extern int sh_closepipe (int *);
 329
 330 extern int file_exists (const char *);
 331 extern int file_isdir (const char  *);
 332 extern int file_iswdir (const char  *);
 333 extern int path_dot_or_dotdot (const char *);
 334 extern int absolute_pathname (const char *);
 335 extern int absolute_program (const char *);
 336
 337 extern char *make_absolute (const char *, const char *);
 338 extern char *base_pathname (char *);
 339 extern char *full_pathname (char *);
 340 extern char *polite_directory_format (char *);
 341 extern char *trim_pathname (char *, int);
 342 extern char *printable_filename (char *, int);
 343
 344 extern char *extract_colon_unit (char *, int *);
 345
 346 extern void tilde_initialize (void);
 347 extern char *bash_tilde_find_word (const char *, int, int *);
 348 extern char *bash_tilde_expand (const char *, int);
 349
 350 extern int group_member (gid_t);
 351 extern char **get_group_list (int *);
 352 extern int *get_group_array (int *);
 353
 354 extern char *conf_standard_path (void);
 355 extern int default_columns (void);
 356
 357 #endif  /* _GENERAL_H_ */