scrypt-1.2.1/libcperciva/util/getopt.h

   1 #ifndef _GETOPT_H_
   2 #define _GETOPT_H_
   3
   4 #include <setjmp.h>
   5 #include <stddef.h>
   6
   7 /**
   8  * This getopt implementation parses options of the following forms:
   9  * -a -b -c foo         (single-character options)
  10  * -abc foo             (packed single-character options)
  11  * -abcfoo              (packed single-character options and an argument)
  12  * --foo bar            (long option)
  13  * --foo=bar            (long option and argument separated by '=')
  14  *
  15  * It does not support abbreviated options (e.g., interpreting --foo as
  16  * --foobar when there are no other --foo* options) since that misfeature
  17  * results in breakage when new options are added.  It also does not support
  18  * options appearing after non-options (e.g., "cp foo bar -R") since that is
  19  * a horrible GNU perversion.
  20  */
  21
  22 /* Work around LLVM bug. */
  23 #ifdef __clang__
  24 #warning Working around bug in LLVM optimizer
  25 #warning For more details see https://llvm.org/bugs/show_bug.cgi?id=27190
  26 #define DO_SETJMP _DO_SETJMP(__LINE__)
  27 #define _DO_SETJMP(x) __DO_SETJMP(x)
  28 #define __DO_SETJMP(x)                                                  \
  29         void * getopt_initloop = && getopt_initloop_ ## x;              \
  30         getopt_initloop_ ## x:
  31 #define DO_LONGJMP                                                      \
  32         goto *getopt_initloop
  33 #else
  34 #define DO_SETJMP                                                       \
  35         sigjmp_buf getopt_initloop;                                     \
  36         if (!getopt_initialized)                                        \
  37                 sigsetjmp(getopt_initloop, 0)
  38 #define DO_LONGJMP                                                      \
  39         siglongjmp(getopt_initloop, 1)
  40 #endif
  41
  42 /* Avoid namespace collisions with libc getopt. */
  43 #define getopt  libcperciva_getopt
  44 #define optarg  libcperciva_optarg
  45 #define optind  libcperciva_optind
  46 #define opterr  libcperciva_opterr
  47 #define optreset        libcperciva_optreset
  48
  49 /* Standard getopt global variables. */
  50 extern const char * optarg;
  51 extern int optind, opterr, optreset;
  52
  53 /* Dummy option string, equal to "(dummy)". */
  54 #define GETOPT_DUMMY getopt_dummy
  55
  56 /**
  57  * GETOPT(argc, argv):
  58  * When called for the first time (or the first time after optreset is set to
  59  * a nonzero value), return GETOPT_DUMMY, aka. "(dummy)".  Thereafter, return
  60  * the next option string and set optarg / optind appropriately; abort if not
  61  * properly initialized when not being called for the first time.
  62  */
  63 #define GETOPT(argc, argv) getopt(argc, argv)
  64
  65 /**
  66  * GETOPT_SWITCH(ch):
  67  * Jump to the appropriate GETOPT_OPT, GETOPT_OPTARG, GETOPT_MISSING_ARG, or
  68  * GETOPT_DEFAULT based on the option string ${ch}.  When called for the first
  69  * time, perform magic to index the options.
  70  *
  71  * GETOPT_SWITCH(ch) is equivalent to "switch (ch)" in a standard getopt loop.
  72  */
  73 #define GETOPT_SWITCH(ch)                                               \
  74         volatile size_t getopt_ln_min = __LINE__;                       \
  75         volatile size_t getopt_ln = getopt_ln_min - 1;          \
  76         volatile int getopt_default_missing = 0;                        \
  77         DO_SETJMP;                                              \
  78         switch (getopt_initialized ? getopt_lookup(ch) + getopt_ln_min : getopt_ln++)
  79
  80 /**
  81  * GETOPT_OPT(os):
  82  * Jump to this point when the option string ${os} is passed to GETOPT_SWITCH.
  83  *
  84  * GETOPT_OPT("-x") is equivalent to "case 'x'" in a standard getopt loop
  85  * which has an optstring containing "x".
  86  */
  87 #define GETOPT_OPT(os)  _GETOPT_OPT(os, __LINE__)
  88 #define _GETOPT_OPT(os, ln)     __GETOPT_OPT(os, ln)
  89 #define __GETOPT_OPT(os, ln)                                            \
  90         case ln:                                                        \
  91                 if (getopt_initialized)                                 \
  92                         goto getopt_skip_ ## ln;                        \
  93                 getopt_register_opt(os, ln - getopt_ln_min, 0);         \
  94                 DO_LONGJMP;                                             \
  95         getopt_skip_ ## ln
  96
  97 /**
  98  * GETOPT_OPTARG(os):
  99  * Jump to this point when the option string ${os} is passed to GETOPT_SWITCH,
 100  * unless no argument is available, in which case jump to GETOPT_MISSING_ARG
 101  * (if present) or GETOPT_DEFAULT (if not).
 102  *
 103  * GETOPT_OPTARG("-x") is equivalent to "case 'x'" in a standard getopt loop
 104  * which has an optstring containing "x:".
 105  */
 106 #define GETOPT_OPTARG(os)       _GETOPT_OPTARG(os, __LINE__)
 107 #define _GETOPT_OPTARG(os, ln)  __GETOPT_OPTARG(os, ln)
 108 #define __GETOPT_OPTARG(os, ln)                                         \
 109         case ln:                                                        \
 110                 if (getopt_initialized)                                 \
 111                         goto getopt_skip_ ## ln;                        \
 112                 getopt_register_opt(os, ln - getopt_ln_min, 1);         \
 113                 DO_LONGJMP;                                             \
 114         getopt_skip_ ## ln
 115
 116 /**
 117  * GETOPT_MISSING_ARG:
 118  * Jump to this point if an option string specified in GETOPT_OPTARG is seen
 119  * but no argument is available.
 120  *
 121  * GETOPT_MISSING_ARG is equivalent to "case ':'" in a standard getopt loop
 122  * which has an optstring starting with ":".  As such, it also has the effect
 123  * of disabling warnings about invalid options, as if opterr had been zeroed.
 124  */
 125 #define GETOPT_MISSING_ARG      _GETOPT_MISSING_ARG(__LINE__)
 126 #define _GETOPT_MISSING_ARG(ln) __GETOPT_MISSING_ARG(ln)
 127 #define __GETOPT_MISSING_ARG(ln)                                        \
 128         case ln:                                                        \
 129                 if (getopt_initialized)                                 \
 130                         goto getopt_skip_ ## ln;                        \
 131                 getopt_register_missing(ln - getopt_ln_min);            \
 132                 DO_LONGJMP;                                             \
 133         getopt_skip_ ## ln
 134
 135 /**
 136  * GETOPT_DEFAULT:
 137  * Jump to this point if an unrecognized option is seen or if an option
 138  * specified in GETOPT_OPTARG is seen, no argument is available, and there is
 139  * no GETOPT_MISSING_ARG label.
 140  *
 141  * GETOPT_DEFAULT is equivalent to "case '?'" in a standard getopt loop.
 142  *
 143  * NOTE: This MUST be present in the GETOPT_SWITCH statement, and MUST occur
 144  * after all other GETOPT_* labels.
 145  */
 146 #define GETOPT_DEFAULT          _GETOPT_DEFAULT(__LINE__)
 147 #define _GETOPT_DEFAULT(ln)     __GETOPT_DEFAULT(ln)
 148 #define __GETOPT_DEFAULT(ln)                                            \
 149                 goto getopt_skip_ ## ln;                                \
 150         case ln:                                                        \
 151                 getopt_initialized = 1;                                 \
 152                 break;                                                  \
 153         default:                                                        \
 154                 if (getopt_initialized)                                 \
 155                         goto getopt_skip_ ## ln;                        \
 156                 if (!getopt_default_missing) {                          \
 157                         getopt_setrange(ln - getopt_ln_min);            \
 158                         getopt_default_missing = 1;                     \
 159                 }                                                       \
 160                 DO_LONGJMP;                                             \
 161         getopt_skip_ ## ln
 162
 163 /*
 164  * The back-end implementation.  These should be considered internal
 165  * interfaces and not used directly.
 166  */
 167 const char * getopt(int, char * const []);
 168 size_t getopt_lookup(const char *);
 169 void getopt_register_opt(const char *, size_t, int);
 170 void getopt_register_missing(size_t);
 171 void getopt_setrange(size_t);
 172 extern const char * getopt_dummy;
 173 extern int getopt_initialized;
 174
 175 #endif /* !_GETOPT_H_ */