/* Copyright (C) 2012-2015 Mark Nunberg.
 *
 * See included LICENSE file for license details.
 */

#include "jsonsl.h"
#include <assert.h>
#include <limits.h>
#include <ctype.h>
#include <bson-memory.h>

#ifdef JSONSL_USE_METRICS
#define XMETRICS             \
   X (STRINGY_INSIGNIFICANT) \
   X (STRINGY_SLOWPATH)      \
   X (ALLOWED_WHITESPACE)    \
   X (QUOTE_FASTPATH)        \
   X (SPECIAL_FASTPATH)      \
   X (SPECIAL_WSPOP)         \
   X (SPECIAL_SLOWPATH)      \
   X (GENERIC)               \
   X (STRUCTURAL_TOKEN)      \
   X (SPECIAL_SWITCHFIRST)   \
   X (STRINGY_CATCH)         \
   X (NUMBER_FASTPATH)       \
   X (ESCAPES)               \
   X (TOTAL)

struct jsonsl_metrics_st {
#define X(m) unsigned long metric_##m;
   XMETRICS
#undef X
};

static struct jsonsl_metrics_st GlobalMetrics = {0};
static unsigned long GenericCounter[0x100] = {0};
static unsigned long StringyCatchCounter[0x100] = {0};

#define INCR_METRIC(m) GlobalMetrics.metric_##m++;

#define INCR_GENERIC(c)   \
   INCR_METRIC (GENERIC); \
   GenericCounter[c]++;

#define INCR_STRINGY_CATCH(c)   \
   INCR_METRIC (STRINGY_CATCH); \
   StringyCatchCounter[c]++;

JSONSL_API
void
jsonsl_dump_global_metrics (void)
{
   int ii;
   printf ("JSONSL Metrics:\n");
#define X(m)                                                        \
   printf ("\t%-30s %20lu (%0.2f%%)\n",                             \
           #m,                                                      \
           GlobalMetrics.metric_##m,                                \
           (float) ((float) (GlobalMetrics.metric_##m /             \
                             (float) GlobalMetrics.metric_TOTAL)) * \
              100);
   XMETRICS
#undef X
   printf ("Generic Characters:\n");
   for (ii = 0; ii < 0xff; ii++) {
      if (GenericCounter[ii]) {
         printf ("\t[ %c ] %lu\n", ii, GenericCounter[ii]);
      }
   }
   printf ("Weird string loop\n");
   for (ii = 0; ii < 0xff; ii++) {
      if (StringyCatchCounter[ii]) {
         printf ("\t[ %c ] %lu\n", ii, StringyCatchCounter[ii]);
      }
   }
}

#else
#define INCR_METRIC(m)
#define INCR_GENERIC(c)
#define INCR_STRINGY_CATCH(c)
JSONSL_API
void
jsonsl_dump_global_metrics (void)
{
}
#endif /* JSONSL_USE_METRICS */

#define CASE_DIGITS \
   case '1':        \
   case '2':        \
   case '3':        \
   case '4':        \
   case '5':        \
   case '6':        \
   case '7':        \
   case '8':        \
   case '9':        \
   case '0':

static unsigned
extract_special (unsigned);
static int
is_special_end (unsigned);
static int
is_allowed_whitespace (unsigned);
static int
is_allowed_escape (unsigned);
static int
is_simple_char (unsigned);
static char
get_escape_equiv (unsigned);

JSONSL_API
jsonsl_t
jsonsl_new (int nlevels)
{
   unsigned int ii;
   struct jsonsl_st *jsn = (struct jsonsl_st *) bson_malloc0 (
      sizeof (*jsn) + ((nlevels - 1) * sizeof (struct jsonsl_state_st)));

   if (nlevels < 0) {
      return NULL;
   }

   jsn->levels_max = (unsigned int) nlevels;
   jsn->max_callback_level = UINT_MAX;
   jsonsl_reset (jsn);
   for (ii = 0; ii < jsn->levels_max; ii++) {
      jsn->stack[ii].level = ii;
   }
   return jsn;
}

JSONSL_API
void
jsonsl_reset (jsonsl_t jsn)
{
   jsn->tok_last = 0;
   jsn->can_insert = 1;
   jsn->pos = 0;
   jsn->level = 0;
   jsn->stopfl = 0;
   jsn->in_escape = 0;
   jsn->expecting = 0;
}

JSONSL_API
void
jsonsl_destroy (jsonsl_t jsn)
{
   if (jsn) {
      bson_free (jsn);
   }
}


#define FASTPARSE_EXHAUSTED 1
#define FASTPARSE_BREAK 0

/*
 * This function is meant to accelerate string parsing, reducing the main loop's
 * check if we are indeed a string.
 *
 * @param jsn the parser
 * @param[in,out] bytes_p A pointer to the current buffer (i.e. current
 * position)
 * @param[in,out] nbytes_p A pointer to the current size of the buffer
 * @return true if all bytes have been exhausted (and thus the main loop can
 * return), false if a special character was examined which requires greater
 * examination.
 */
static int
jsonsl__str_fastparse (jsonsl_t jsn,
                       const jsonsl_uchar_t **bytes_p,
                       size_t *nbytes_p)
{
   const jsonsl_uchar_t *bytes = *bytes_p;
   const jsonsl_uchar_t *end;
   for (end = bytes + *nbytes_p; bytes != end; bytes++) {
      if (
#ifdef JSONSL_USE_WCHAR
         *bytes >= 0x100 ||
#endif /* JSONSL_USE_WCHAR */
         (is_simple_char (*bytes))) {
         INCR_METRIC (TOTAL);
         INCR_METRIC (STRINGY_INSIGNIFICANT);
      } else {
         /* Once we're done here, re-calculate the position variables */
         jsn->pos += (bytes - *bytes_p);
         *nbytes_p -= (bytes - *bytes_p);
         *bytes_p = bytes;
         return FASTPARSE_BREAK;
      }
   }

   /* Once we're done here, re-calculate the position variables */
   jsn->pos += (bytes - *bytes_p);
   return FASTPARSE_EXHAUSTED;
}

/* Functions exactly like str_fastparse, except it also accepts a 'state'
 * argument, since the number's value is updated in the state. */
static int
jsonsl__num_fastparse (jsonsl_t jsn,
                       const jsonsl_uchar_t **bytes_p,
                       size_t *nbytes_p,
                       struct jsonsl_state_st *state)
{
   int exhausted = 1;
   size_t nbytes = *nbytes_p;
   const jsonsl_uchar_t *bytes = *bytes_p;

   for (; nbytes; nbytes--, bytes++) {
      jsonsl_uchar_t c = *bytes;
      if (isdigit (c)) {
         INCR_METRIC (TOTAL);
         INCR_METRIC (NUMBER_FASTPATH);
         state->nelem = (state->nelem * 10) + (c - 0x30);
      } else {
         exhausted = 0;
         break;
      }
   }
   jsn->pos += (*nbytes_p - nbytes);
   if (exhausted) {
      return FASTPARSE_EXHAUSTED;
   }
   *nbytes_p = nbytes;
   *bytes_p = bytes;
   return FASTPARSE_BREAK;
}

JSONSL_API
void
jsonsl_feed (jsonsl_t jsn, const jsonsl_char_t *bytes, size_t nbytes)
{
#define INVOKE_ERROR(eb)                                                  \
   if (jsn->error_callback (jsn, JSONSL_ERROR_##eb, state, (char *) c)) { \
      goto GT_AGAIN;                                                      \
   }                                                                      \
   return;

#define STACK_PUSH                                                      \
   if (jsn->level >= (levels_max - 1)) {                                \
      jsn->error_callback (                                             \
         jsn, JSONSL_ERROR_LEVELS_EXCEEDED, state, (char *) c);         \
      return;                                                           \
   }                                                                    \
   state = jsn->stack + (++jsn->level);                                 \
   state->ignore_callback = jsn->stack[jsn->level - 1].ignore_callback; \
   state->pos_begin = jsn->pos;

#define STACK_POP_NOPOS       \
   state->pos_cur = jsn->pos; \
   state = jsn->stack + (--jsn->level);


#define STACK_POP   \
   STACK_POP_NOPOS; \
   state->pos_cur = jsn->pos;

#define CALLBACK_AND_POP_NOPOS(T) \
   state->pos_cur = jsn->pos;     \
   DO_CALLBACK (T, POP);          \
   state->nescapes = 0;           \
   state = jsn->stack + (--jsn->level);

#define CALLBACK_AND_POP(T)    \
   CALLBACK_AND_POP_NOPOS (T); \
   state->pos_cur = jsn->pos;

#define SPECIAL_POP            \
   CALLBACK_AND_POP (SPECIAL); \
   jsn->expecting = 0;         \
   jsn->tok_last = 0;

#define CUR_CHAR (*(jsonsl_uchar_t *) c)

#define DO_CALLBACK(T, action)                                        \
   if (jsn->call_##T && jsn->max_callback_level > state->level &&     \
       state->ignore_callback == 0) {                                 \
      if (jsn->action_callback_##action) {                            \
         jsn->action_callback_##action (                              \
            jsn, JSONSL_ACTION_##action, state, (jsonsl_char_t *) c); \
      } else if (jsn->action_callback) {                              \
         jsn->action_callback (                                       \
            jsn, JSONSL_ACTION_##action, state, (jsonsl_char_t *) c); \
      }                                                               \
      if (jsn->stopfl) {                                              \
         return;                                                      \
      }                                                               \
   }

/**
 * Verifies that we are able to insert the (non-string) item into a hash.
 */
#define ENSURE_HVAL                                               \
   if (state->nelem % 2 == 0 && state->type == JSONSL_T_OBJECT) { \
      INVOKE_ERROR (HKEY_EXPECTED);                               \
   }

#define VERIFY_SPECIAL(lit)                              \
   if (CUR_CHAR != (lit)[jsn->pos - state->pos_begin]) { \
      INVOKE_ERROR (SPECIAL_EXPECTED);                   \
   }

#define STATE_SPECIAL_LENGTH (state)->nescapes

#define IS_NORMAL_NUMBER                                  \
   ((state)->special_flags == JSONSL_SPECIALf_UNSIGNED || \
    (state)->special_flags == JSONSL_SPECIALf_SIGNED)

#define STATE_NUM_LAST jsn->tok_last

#define CONTINUE_NEXT_CHAR() continue

   const jsonsl_uchar_t *c = (jsonsl_uchar_t *) bytes;
   size_t levels_max = jsn->levels_max;
   struct jsonsl_state_st *state = jsn->stack + jsn->level;
   jsn->base = bytes;

   for (; nbytes; nbytes--, jsn->pos++, c++) {
      unsigned state_type;
      INCR_METRIC (TOTAL);

   GT_AGAIN:
      state_type = state->type;
      /* Most common type is typically a string: */
      if (state_type & JSONSL_Tf_STRINGY) {
         /* Special escape handling for some stuff */
         if (jsn->in_escape) {
            jsn->in_escape = 0;
            if (!is_allowed_escape (CUR_CHAR)) {
               INVOKE_ERROR (ESCAPE_INVALID);
            } else if (CUR_CHAR == 'u') {
               DO_CALLBACK (UESCAPE, UESCAPE);
               if (jsn->return_UESCAPE) {
                  return;
               }
            }
            CONTINUE_NEXT_CHAR ();
         }

         if (jsonsl__str_fastparse (jsn, &c, &nbytes) == FASTPARSE_EXHAUSTED) {
            /* No need to readjust variables as we've exhausted the iterator */
            return;
         } else {
            if (CUR_CHAR == '"') {
               goto GT_QUOTE;
            } else if (CUR_CHAR == '\\') {
               goto GT_ESCAPE;
            } else {
               INVOKE_ERROR (WEIRD_WHITESPACE);
            }
         }
         INCR_METRIC (STRINGY_SLOWPATH);

      } else if (state_type == JSONSL_T_SPECIAL) {
         /* Fast track for signed/unsigned */
         if (IS_NORMAL_NUMBER) {
            if (jsonsl__num_fastparse (jsn, &c, &nbytes, state) ==
                FASTPARSE_EXHAUSTED) {
               return;
            } else {
               goto GT_SPECIAL_NUMERIC;
            }
         } else if (state->special_flags == JSONSL_SPECIALf_DASH) {
            if (!isdigit (CUR_CHAR)) {
               INVOKE_ERROR (INVALID_NUMBER);
            }

            if (CUR_CHAR == '0') {
               state->special_flags =
                  JSONSL_SPECIALf_ZERO | JSONSL_SPECIALf_SIGNED;
            } else if (isdigit (CUR_CHAR)) {
               state->special_flags = JSONSL_SPECIALf_SIGNED;
               state->nelem = CUR_CHAR - 0x30;
            } else {
               INVOKE_ERROR (INVALID_NUMBER);
            }
            CONTINUE_NEXT_CHAR ();

         } else if (state->special_flags == JSONSL_SPECIALf_ZERO) {
            if (isdigit (CUR_CHAR)) {
               /* Following a zero! */
               INVOKE_ERROR (INVALID_NUMBER);
            }
            /* Unset the 'zero' flag: */
            if (state->special_flags & JSONSL_SPECIALf_SIGNED) {
               state->special_flags = JSONSL_SPECIALf_SIGNED;
            } else {
               state->special_flags = JSONSL_SPECIALf_UNSIGNED;
            }
            goto GT_SPECIAL_NUMERIC;
         }

         if (state->special_flags & JSONSL_SPECIALf_NUMERIC) {
         GT_SPECIAL_NUMERIC:
            switch (CUR_CHAR) {
               CASE_DIGITS
               STATE_NUM_LAST = '1';
               CONTINUE_NEXT_CHAR ();

            case '.':
               if (state->special_flags & JSONSL_SPECIALf_FLOAT) {
                  INVOKE_ERROR (INVALID_NUMBER);
               }
               state->special_flags |= JSONSL_SPECIALf_FLOAT;
               STATE_NUM_LAST = '.';
               CONTINUE_NEXT_CHAR ();

            case 'e':
            case 'E':
               if (state->special_flags & JSONSL_SPECIALf_EXPONENT) {
                  INVOKE_ERROR (INVALID_NUMBER);
               }
               state->special_flags |= JSONSL_SPECIALf_EXPONENT;
               STATE_NUM_LAST = 'e';
               CONTINUE_NEXT_CHAR ();

            case '-':
            case '+':
               if (STATE_NUM_LAST != 'e') {
                  INVOKE_ERROR (INVALID_NUMBER);
               }
               STATE_NUM_LAST = '-';
               CONTINUE_NEXT_CHAR ();

            default:
               if (is_special_end (CUR_CHAR)) {
                  goto GT_SPECIAL_POP;
               }
               INVOKE_ERROR (INVALID_NUMBER);
               break;
            }
         }
         /* else if (!NUMERIC) */
         if (!is_special_end (CUR_CHAR)) {
            STATE_SPECIAL_LENGTH++;

            /* Verify TRUE, FALSE, NULL */
            if (state->special_flags == JSONSL_SPECIALf_TRUE) {
               VERIFY_SPECIAL ("true");
            } else if (state->special_flags == JSONSL_SPECIALf_FALSE) {
               VERIFY_SPECIAL ("false");
            } else if (state->special_flags == JSONSL_SPECIALf_NULL) {
               VERIFY_SPECIAL ("null");
            }
            INCR_METRIC (SPECIAL_FASTPATH);
            CONTINUE_NEXT_CHAR ();
         }

      GT_SPECIAL_POP:
         jsn->can_insert = 0;
         if (IS_NORMAL_NUMBER) {
            /* Nothing */
         } else if (state->special_flags == JSONSL_SPECIALf_ZERO ||
                    state->special_flags ==
                       (JSONSL_SPECIALf_ZERO | JSONSL_SPECIALf_SIGNED)) {
            /* 0 is unsigned! */
            state->special_flags = JSONSL_SPECIALf_UNSIGNED;
         } else if (state->special_flags == JSONSL_SPECIALf_DASH) {
            /* Still in dash! */
            INVOKE_ERROR (INVALID_NUMBER);
         } else if (state->special_flags & JSONSL_SPECIALf_NUMERIC) {
            /* Check that we're not at the end of a token */
            if (STATE_NUM_LAST != '1') {
               INVOKE_ERROR (INVALID_NUMBER);
            }
         } else if (state->special_flags == JSONSL_SPECIALf_TRUE) {
            if (STATE_SPECIAL_LENGTH != 4) {
               INVOKE_ERROR (SPECIAL_INCOMPLETE);
            }
            state->nelem = 1;
         } else if (state->special_flags == JSONSL_SPECIALf_FALSE) {
            if (STATE_SPECIAL_LENGTH != 5) {
               INVOKE_ERROR (SPECIAL_INCOMPLETE);
            }
         } else if (state->special_flags == JSONSL_SPECIALf_NULL) {
            if (STATE_SPECIAL_LENGTH != 4) {
               INVOKE_ERROR (SPECIAL_INCOMPLETE);
            }
         }
         SPECIAL_POP;
         jsn->expecting = ',';
         if (is_allowed_whitespace (CUR_CHAR)) {
            CONTINUE_NEXT_CHAR ();
         }
         /**
          * This works because we have a non-whitespace token
          * which is not a special token. If this is a structural
          * character then it will be gracefully handled by the
          * switch statement. Otherwise it will default to the 'special'
          * state again,
          */
         goto GT_STRUCTURAL_TOKEN;
      } else if (is_allowed_whitespace (CUR_CHAR)) {
         INCR_METRIC (ALLOWED_WHITESPACE);
         /* So we're not special. Harmless insignificant whitespace
          * passthrough
          */
         CONTINUE_NEXT_CHAR ();
      } else if (extract_special (CUR_CHAR)) {
         /* not a string, whitespace, or structural token. must be special */
         goto GT_SPECIAL_BEGIN;
      }

      INCR_GENERIC (CUR_CHAR);

      if (CUR_CHAR == '"') {
      GT_QUOTE:
         jsn->can_insert = 0;
         switch (state_type) {
         /* the end of a string or hash key */
         case JSONSL_T_STRING:
            CALLBACK_AND_POP (STRING);
            CONTINUE_NEXT_CHAR ();
         case JSONSL_T_HKEY:
            CALLBACK_AND_POP (HKEY);
            CONTINUE_NEXT_CHAR ();

         case JSONSL_T_OBJECT:
            state->nelem++;
            if ((state->nelem - 1) % 2) {
               /* Odd, this must be a hash value */
               if (jsn->tok_last != ':') {
                  INVOKE_ERROR (MISSING_TOKEN);
               }
               jsn->expecting = ','; /* Can't figure out what to expect next */
               jsn->tok_last = 0;

               STACK_PUSH;
               state->type = JSONSL_T_STRING;
               DO_CALLBACK (STRING, PUSH);

            } else {
               /* hash key */
               if (jsn->expecting != '"') {
                  INVOKE_ERROR (STRAY_TOKEN);
               }
               jsn->tok_last = 0;
               jsn->expecting = ':';

               STACK_PUSH;
               state->type = JSONSL_T_HKEY;
               DO_CALLBACK (HKEY, PUSH);
            }
            CONTINUE_NEXT_CHAR ();

         case JSONSL_T_LIST:
            state->nelem++;
            STACK_PUSH;
            state->type = JSONSL_T_STRING;
            jsn->expecting = ',';
            jsn->tok_last = 0;
            DO_CALLBACK (STRING, PUSH);
            CONTINUE_NEXT_CHAR ();

         case JSONSL_T_SPECIAL:
            INVOKE_ERROR (STRAY_TOKEN);
            break;

         default:
            INVOKE_ERROR (STRING_OUTSIDE_CONTAINER);
            break;
         } /* switch(state->type) */
      } else if (CUR_CHAR == '\\') {
      GT_ESCAPE:
         INCR_METRIC (ESCAPES);
         /* Escape */
         if ((state->type & JSONSL_Tf_STRINGY) == 0) {
            INVOKE_ERROR (ESCAPE_OUTSIDE_STRING);
         }
         state->nescapes++;
         jsn->in_escape = 1;
         CONTINUE_NEXT_CHAR ();
      } /* " or \ */

   GT_STRUCTURAL_TOKEN:
      switch (CUR_CHAR) {
      case ':':
         INCR_METRIC (STRUCTURAL_TOKEN);
         if (jsn->expecting != CUR_CHAR) {
            INVOKE_ERROR (STRAY_TOKEN);
         }
         jsn->tok_last = ':';
         jsn->can_insert = 1;
         jsn->expecting = '"';
         CONTINUE_NEXT_CHAR ();

      case ',':
         INCR_METRIC (STRUCTURAL_TOKEN);
         /**
          * The comma is one of the more generic tokens.
          * In the context of an OBJECT, the can_insert flag
          * should never be set, and no other action is
          * necessary.
          */
         if (jsn->expecting != CUR_CHAR) {
            /* make this branch execute only when we haven't manually
             * just placed the ',' in the expecting register.
             */
            INVOKE_ERROR (STRAY_TOKEN);
         }

         if (state->type == JSONSL_T_OBJECT) {
            /* end of hash value, expect a string as a hash key */
            jsn->expecting = '"';
         } else {
            jsn->can_insert = 1;
         }

         jsn->tok_last = ',';
         jsn->expecting = '"';
         CONTINUE_NEXT_CHAR ();

      /* new list or object */
      /* hashes are more common */
      case '{':
      case '[':
         INCR_METRIC (STRUCTURAL_TOKEN);
         if (!jsn->can_insert) {
            INVOKE_ERROR (CANT_INSERT);
         }

         ENSURE_HVAL;
         state->nelem++;

         STACK_PUSH;
         /* because the constants match the opening delimiters, we can do this:
          */
         state->type = CUR_CHAR;
         state->nelem = 0;
         jsn->can_insert = 1;
         if (CUR_CHAR == '{') {
            /* If we're a hash, we expect a key first, which is quouted */
            jsn->expecting = '"';
         }
         if (CUR_CHAR == JSONSL_T_OBJECT) {
            DO_CALLBACK (OBJECT, PUSH);
         } else {
            DO_CALLBACK (LIST, PUSH);
         }
         jsn->tok_last = 0;
         CONTINUE_NEXT_CHAR ();

      /* closing of list or object */
      case '}':
      case ']':
         INCR_METRIC (STRUCTURAL_TOKEN);
         if (jsn->tok_last == ',' && jsn->options.allow_trailing_comma == 0) {
            INVOKE_ERROR (TRAILING_COMMA);
         }

         jsn->can_insert = 0;
         jsn->level--;
         jsn->expecting = ',';
         jsn->tok_last = 0;
         if (CUR_CHAR == ']') {
            if (state->type != '[') {
               INVOKE_ERROR (BRACKET_MISMATCH);
            }
            DO_CALLBACK (LIST, POP);
         } else {
            if (state->type != '{') {
               INVOKE_ERROR (BRACKET_MISMATCH);
            } else if (state->nelem && state->nelem % 2 != 0) {
               INVOKE_ERROR (VALUE_EXPECTED);
            }
            DO_CALLBACK (OBJECT, POP);
         }
         state = jsn->stack + jsn->level;
         state->pos_cur = jsn->pos;
         CONTINUE_NEXT_CHAR ();

      default:
      GT_SPECIAL_BEGIN:
         /**
          * Not a string, not a structural token, and not benign whitespace.
          * Technically we should iterate over the character always, but since
          * we are not doing full numerical/value decoding anyway (but only
          * hinting),
          * we only check upon entry.
          */
         if (state->type != JSONSL_T_SPECIAL) {
            int special_flags = extract_special (CUR_CHAR);
            if (!special_flags) {
               /**
                * Try to do some heuristics here anyway to figure out what kind
                * of
                * error this is. The 'special' case is a fallback scenario
                * anyway.
                */
               if (CUR_CHAR == '\0') {
                  INVOKE_ERROR (FOUND_NULL_BYTE);
               } else if (CUR_CHAR < 0x20) {
                  INVOKE_ERROR (WEIRD_WHITESPACE);
               } else {
                  INVOKE_ERROR (SPECIAL_EXPECTED);
               }
            }
            ENSURE_HVAL;
            state->nelem++;
            if (!jsn->can_insert) {
               INVOKE_ERROR (CANT_INSERT);
            }
            STACK_PUSH;
            state->type = JSONSL_T_SPECIAL;
            state->special_flags = special_flags;
            STATE_SPECIAL_LENGTH = 1;

            if (special_flags == JSONSL_SPECIALf_UNSIGNED) {
               state->nelem = CUR_CHAR - 0x30;
               STATE_NUM_LAST = '1';
            } else {
               STATE_NUM_LAST = '-';
               state->nelem = 0;
            }
            DO_CALLBACK (SPECIAL, PUSH);
         }
         CONTINUE_NEXT_CHAR ();
      }
   }
}

JSONSL_API
const char *
jsonsl_strerror (jsonsl_error_t err)
{
   if (err == JSONSL_ERROR_SUCCESS) {
      return "SUCCESS";
   }
#define X(t)                    \
   if (err == JSONSL_ERROR_##t) \
      return #t;
   JSONSL_XERR;
#undef X
   return "<UNKNOWN_ERROR>";
}

JSONSL_API
const char *
jsonsl_strtype (jsonsl_type_t type)
{
#define X(o, c)              \
   if (type == JSONSL_T_##o) \
      return #o;
   JSONSL_XTYPE
#undef X
   return "UNKNOWN TYPE";
}

/*
 *
 * JPR/JSONPointer functions
 *
 *
 */
#ifndef JSONSL_NO_JPR
static jsonsl_jpr_type_t
populate_component (char *in,
                    struct jsonsl_jpr_component_st *component,
                    char **next,
                    jsonsl_error_t *errp)
{
   unsigned long pctval;
   char *c = NULL, *outp = NULL, *end = NULL;
   size_t input_len;
   jsonsl_jpr_type_t ret = JSONSL_PATH_NONE;

   if (*next == NULL || *(*next) == '\0') {
      return JSONSL_PATH_NONE;
   }

   /* Replace the next / with a NULL */
   *next = strstr (in, "/");
   if (*next != NULL) {
      *(*next) = '\0'; /* drop the forward slash */
      input_len = *next - in;
      end = *next;
      *next += 1; /* next character after the '/' */
   } else {
      input_len = strlen (in);
      end = in + input_len + 1;
   }

   component->pstr = in;

   /* Check for special components of interest */
   if (*in == JSONSL_PATH_WILDCARD_CHAR && input_len == 1) {
      /* Lone wildcard */
      ret = JSONSL_PATH_WILDCARD;
      goto GT_RET;
   } else if (isdigit (*in)) {
      /* ASCII Numeric */
      char *endptr;
      component->idx = strtoul (in, &endptr, 10);
      if (endptr && *endptr == '\0') {
         ret = JSONSL_PATH_NUMERIC;
         goto GT_RET;
      }
   }

   /* Default, it's a string */
   ret = JSONSL_PATH_STRING;
   for (c = outp = in; c < end; c++, outp++) {
      char origc;
      if (*c != '%') {
         goto GT_ASSIGN;
      }
      /*
       * c = { [+0] = '%', [+1] = 'b', [+2] = 'e', [+3] = '\0' }
       */

      /* Need %XX */
      if (c + 2 >= end) {
         *errp = JSONSL_ERROR_PERCENT_BADHEX;
         return JSONSL_PATH_INVALID;
      }
      if (!(isxdigit (*(c + 1)) && isxdigit (*(c + 2)))) {
         *errp = JSONSL_ERROR_PERCENT_BADHEX;
         return JSONSL_PATH_INVALID;
      }

      /* Temporarily null-terminate the characters */
      origc = *(c + 3);
      *(c + 3) = '\0';
      pctval = strtoul (c + 1, NULL, 16);
      *(c + 3) = origc;

      *outp = (char) pctval;
      c += 2;
      continue;

   GT_ASSIGN:
      *outp = *c;
   }
   /* Null-terminate the string */
   for (; outp < c; outp++) {
      *outp = '\0';
   }

GT_RET:
   component->ptype = ret;
   if (ret != JSONSL_PATH_WILDCARD) {
      component->len = strlen (component->pstr);
   }
   return ret;
}

JSONSL_API
jsonsl_jpr_t
jsonsl_jpr_new (const char *path, jsonsl_error_t *errp)
{
   char *my_copy = NULL;
   int count, curidx;
   struct jsonsl_jpr_st *ret = NULL;
   struct jsonsl_jpr_component_st *components = NULL;
   size_t origlen;
   jsonsl_error_t errstacked;

#define JPR_BAIL(err) \
   *errp = err;       \
   goto GT_ERROR;

   if (errp == NULL) {
      errp = &errstacked;
   }

   if (path == NULL || *path != '/') {
      JPR_BAIL (JSONSL_ERROR_JPR_NOROOT);
   }

   count = 1;
   path++;
   {
      const char *c = path;
      for (; *c; c++) {
         if (*c == '/') {
            count++;
            if (*(c + 1) == '/') {
               JPR_BAIL (JSONSL_ERROR_JPR_DUPSLASH);
            }
         }
      }
   }
   if (*path) {
      count++;
   }

   components =
      (struct jsonsl_jpr_component_st *) malloc (sizeof (*components) * count);
   if (!components) {
      JPR_BAIL (JSONSL_ERROR_ENOMEM);
   }

   my_copy = (char *) malloc (strlen (path) + 1);
   if (!my_copy) {
      JPR_BAIL (JSONSL_ERROR_ENOMEM);
   }

   strcpy (my_copy, path);

   components[0].ptype = JSONSL_PATH_ROOT;

   if (*my_copy) {
      char *cur = my_copy;
      int pathret = JSONSL_PATH_STRING;
      curidx = 1;
      while (pathret > 0 && curidx < count) {
         pathret = populate_component (cur, components + curidx, &cur, errp);
         if (pathret > 0) {
            curidx++;
         } else {
            break;
         }
      }

      if (pathret == JSONSL_PATH_INVALID) {
         JPR_BAIL (JSONSL_ERROR_JPR_BADPATH);
      }
   } else {
      curidx = 1;
   }

   path--; /*revert path to leading '/' */
   origlen = strlen (path) + 1;
   ret = (struct jsonsl_jpr_st *) malloc (sizeof (*ret));
   if (!ret) {
      JPR_BAIL (JSONSL_ERROR_ENOMEM);
   }
   ret->orig = (char *) malloc (origlen);
   if (!ret->orig) {
      JPR_BAIL (JSONSL_ERROR_ENOMEM);
   }
   ret->components = components;
   ret->ncomponents = curidx;
   ret->basestr = my_copy;
   ret->norig = origlen - 1;
   strcpy (ret->orig, path);

   return ret;

GT_ERROR:
   free (my_copy);
   free (components);
   if (ret) {
      free (ret->orig);
   }
   free (ret);
   return NULL;
#undef JPR_BAIL
}

void
jsonsl_jpr_destroy (jsonsl_jpr_t jpr)
{
   free (jpr->components);
   free (jpr->basestr);
   free (jpr->orig);
   free (jpr);
}

/**
 * Call when there is a possibility of a match, either as a final match or
 * as a path within a match
 * @param jpr The JPR path
 * @param component Component corresponding to the current element
 * @param prlevel The level of the *parent*
 * @param chtype The type of the child
 * @return Match status
 */
static jsonsl_jpr_match_t
jsonsl__match_continue (jsonsl_jpr_t jpr,
                        const struct jsonsl_jpr_component_st *component,
                        unsigned prlevel,
                        unsigned chtype)
{
   const struct jsonsl_jpr_component_st *next_comp = component + 1;
   if (prlevel == jpr->ncomponents - 1) {
      /* This is the match. Check the expected type of the match against
       * the child */
      if (jpr->match_type == 0 || jpr->match_type == chtype) {
         return JSONSL_MATCH_COMPLETE;
      } else {
         return JSONSL_MATCH_TYPE_MISMATCH;
      }
   }
   if (chtype == JSONSL_T_LIST) {
      if (next_comp->ptype == JSONSL_PATH_NUMERIC) {
         return JSONSL_MATCH_POSSIBLE;
      } else {
         return JSONSL_MATCH_TYPE_MISMATCH;
      }
   } else if (chtype == JSONSL_T_OBJECT) {
      if (next_comp->ptype == JSONSL_PATH_NUMERIC) {
         return JSONSL_MATCH_TYPE_MISMATCH;
      } else {
         return JSONSL_MATCH_POSSIBLE;
      }
   } else {
      return JSONSL_MATCH_TYPE_MISMATCH;
   }
}

JSONSL_API
jsonsl_jpr_match_t
jsonsl_path_match (jsonsl_jpr_t jpr,
                   const struct jsonsl_state_st *parent,
                   const struct jsonsl_state_st *child,
                   const char *key,
                   size_t nkey)
{
   const struct jsonsl_jpr_component_st *comp;
   if (!parent) {
      /* No parent. Return immediately since it's always a match */
      return jsonsl__match_continue (jpr, jpr->components, 0, child->type);
   }

   comp = jpr->components + parent->level;

   /* note that we don't need to verify the type of the match, this is
    * always done through the previous call to jsonsl__match_continue.
    * If we are in a POSSIBLE tree then we can be certain the types (at
    * least at this level) are correct */
   if (parent->type == JSONSL_T_OBJECT) {
      if (comp->len != nkey || strncmp (key, comp->pstr, nkey) != 0) {
         return JSONSL_MATCH_NOMATCH;
      }
   } else {
      if (comp->idx != parent->nelem - 1) {
         return JSONSL_MATCH_NOMATCH;
      }
   }
   return jsonsl__match_continue (jpr, comp, parent->level, child->type);
}

JSONSL_API
jsonsl_jpr_match_t
jsonsl_jpr_match (jsonsl_jpr_t jpr,
                  unsigned int parent_type,
                  unsigned int parent_level,
                  const char *key,
                  size_t nkey)
{
   /* find our current component. This is the child level */
   int cmpret;
   struct jsonsl_jpr_component_st *p_component;
   p_component = jpr->components + parent_level;

   if (parent_level >= jpr->ncomponents) {
      return JSONSL_MATCH_NOMATCH;
   }

   /* Lone query for 'root' element. Always matches */
   if (parent_level == 0) {
      if (jpr->ncomponents == 1) {
         return JSONSL_MATCH_COMPLETE;
      } else {
         return JSONSL_MATCH_POSSIBLE;
      }
   }

   /* Wildcard, always matches */
   if (p_component->ptype == JSONSL_PATH_WILDCARD) {
      if (parent_level == jpr->ncomponents - 1) {
         return JSONSL_MATCH_COMPLETE;
      } else {
         return JSONSL_MATCH_POSSIBLE;
      }
   }

   /* Check numeric array index. This gets its special block so we can avoid
    * string comparisons */
   if (p_component->ptype == JSONSL_PATH_NUMERIC) {
      if (parent_type == JSONSL_T_LIST) {
         if (p_component->idx != nkey) {
            /* Wrong index */
            return JSONSL_MATCH_NOMATCH;
         } else {
            if (parent_level == jpr->ncomponents - 1) {
               /* This is the last element of the path */
               return JSONSL_MATCH_COMPLETE;
            } else {
               /* Intermediate element */
               return JSONSL_MATCH_POSSIBLE;
            }
         }
      } else if (p_component->is_arridx) {
         /* Numeric and an array index (set explicitly by user). But not
          * a list for a parent */
         return JSONSL_MATCH_TYPE_MISMATCH;
      }
   } else if (parent_type == JSONSL_T_LIST) {
      return JSONSL_MATCH_TYPE_MISMATCH;
   }

   /* Check lengths */
   if (p_component->len != nkey) {
      return JSONSL_MATCH_NOMATCH;
   }

   /* Check string comparison */
   cmpret = strncmp (p_component->pstr, key, nkey);
   if (cmpret == 0) {
      if (parent_level == jpr->ncomponents - 1) {
         return JSONSL_MATCH_COMPLETE;
      } else {
         return JSONSL_MATCH_POSSIBLE;
      }
   }

   return JSONSL_MATCH_NOMATCH;
}

JSONSL_API
void
jsonsl_jpr_match_state_init (jsonsl_t jsn, jsonsl_jpr_t *jprs, size_t njprs)
{
   size_t ii, *firstjmp;
   if (njprs == 0) {
      return;
   }
   jsn->jprs = (jsonsl_jpr_t *) malloc (sizeof (jsonsl_jpr_t) * njprs);
   jsn->jpr_count = njprs;
   jsn->jpr_root =
      (size_t *) calloc (1, sizeof (size_t) * njprs * jsn->levels_max);
   memcpy (jsn->jprs, jprs, sizeof (jsonsl_jpr_t) * njprs);
   /* Set the initial jump table values */

   firstjmp = jsn->jpr_root;
   for (ii = 0; ii < njprs; ii++) {
      firstjmp[ii] = ii + 1;
   }
}

JSONSL_API
void
jsonsl_jpr_match_state_cleanup (jsonsl_t jsn)
{
   if (jsn->jpr_count == 0) {
      return;
   }

   free (jsn->jpr_root);
   free (jsn->jprs);
   jsn->jprs = NULL;
   jsn->jpr_root = NULL;
   jsn->jpr_count = 0;
}

/**
 * This function should be called exactly once on each element...
 * This should also be called in recursive order, since we rely
 * on the parent having been initalized for a match.
 *
 * Since the parent is checked for a match as well, we maintain a 'serial'
 * counter.
 * Whenever we traverse an element, we expect the serial to be the same as a
 * global
 * integer. If they do not match, we re-initialize the context, and set the
 * serial.
 *
 * This ensures a type of consistency without having a proactive reset by the
 * main lexer itself.
 *
 */
JSONSL_API
jsonsl_jpr_t
jsonsl_jpr_match_state (jsonsl_t jsn,
                        struct jsonsl_state_st *state,
                        const char *key,
                        size_t nkey,
                        jsonsl_jpr_match_t *out)
{
   struct jsonsl_state_st *parent_state;
   jsonsl_jpr_t ret = NULL;

   /* Jump and JPR tables for our own state and the parent state */
   size_t *jmptable, *pjmptable;
   size_t jmp_cur, ii, ourjmpidx;

   if (!jsn->jpr_root) {
      *out = JSONSL_MATCH_NOMATCH;
      return NULL;
   }

   pjmptable = jsn->jpr_root + (jsn->jpr_count * (state->level - 1));
   jmptable = pjmptable + jsn->jpr_count;

   /* If the parent cannot match, then invalidate it */
   if (*pjmptable == 0) {
      *jmptable = 0;
      *out = JSONSL_MATCH_NOMATCH;
      return NULL;
   }

   parent_state = jsn->stack + state->level - 1;

   if (parent_state->type == JSONSL_T_LIST) {
      nkey = (size_t) parent_state->nelem;
   }

   *jmptable = 0;
   ourjmpidx = 0;
   memset (jmptable, 0, sizeof (int) * jsn->jpr_count);

   for (ii = 0; ii < jsn->jpr_count; ii++) {
      jmp_cur = pjmptable[ii];
      if (jmp_cur) {
         jsonsl_jpr_t jpr = jsn->jprs[jmp_cur - 1];
         *out = jsonsl_jpr_match (
            jpr, parent_state->type, parent_state->level, key, nkey);
         if (*out == JSONSL_MATCH_COMPLETE) {
            ret = jpr;
            *jmptable = 0;
            return ret;
         } else if (*out == JSONSL_MATCH_POSSIBLE) {
            jmptable[ourjmpidx] = ii + 1;
            ourjmpidx++;
         }
      } else {
         break;
      }
   }
   if (!*jmptable) {
      *out = JSONSL_MATCH_NOMATCH;
   }
   return NULL;
}

JSONSL_API
const char *
jsonsl_strmatchtype (jsonsl_jpr_match_t match)
{
#define X(T, v)                   \
   if (match == JSONSL_MATCH_##T) \
      return #T;
   JSONSL_XMATCH
#undef X
   return "<UNKNOWN>";
}

#endif /* JSONSL_WITH_JPR */

static char *
jsonsl__writeutf8 (uint32_t pt, char *out)
{
#define ADD_OUTPUT(c) \
   *out = (char) (c); \
   out++;

   if (pt < 0x80) {
      ADD_OUTPUT (pt);
   } else if (pt < 0x800) {
      ADD_OUTPUT ((pt >> 6) | 0xC0);
      ADD_OUTPUT ((pt & 0x3F) | 0x80);
   } else if (pt < 0x10000) {
      ADD_OUTPUT ((pt >> 12) | 0xE0);
      ADD_OUTPUT (((pt >> 6) & 0x3F) | 0x80);
      ADD_OUTPUT ((pt & 0x3F) | 0x80);
   } else {
      ADD_OUTPUT ((pt >> 18) | 0xF0);
      ADD_OUTPUT (((pt >> 12) & 0x3F) | 0x80);
      ADD_OUTPUT (((pt >> 6) & 0x3F) | 0x80);
      ADD_OUTPUT ((pt & 0x3F) | 0x80);
   }
   return out;
#undef ADD_OUTPUT
}

/* Thanks snej (https://github.com/mnunberg/jsonsl/issues/9) */
static int
jsonsl__digit2int (char ch)
{
   int d = ch - '0';
   if ((unsigned) d < 10) {
      return d;
   }
   d = ch - 'a';
   if ((unsigned) d < 6) {
      return d + 10;
   }
   d = ch - 'A';
   if ((unsigned) d < 6) {
      return d + 10;
   }
   return -1;
}

/* Assume 's' is at least 4 bytes long */
static int
jsonsl__get_uescape_16 (const char *s)
{
   int ret = 0;
   int cur;

#define GET_DIGIT(off)               \
   cur = jsonsl__digit2int (s[off]); \
   if (cur == -1) {                  \
      return -1;                     \
   }                                 \
   ret |= (cur << (12 - (off * 4)));

   GET_DIGIT (0);
   GET_DIGIT (1);
   GET_DIGIT (2);
   GET_DIGIT (3);
#undef GET_DIGIT
   return ret;
}

/**
 * Utility function to convert escape sequences
 */
JSONSL_API
size_t
jsonsl_util_unescape_ex (const char *in,
                         char *out,
                         size_t len,
                         const int toEscape[128],
                         unsigned *oflags,
                         jsonsl_error_t *err,
                         const char **errat)
{
   const unsigned char *c = (const unsigned char *) in;
   char *begin_p = out;
   unsigned oflags_s;
   uint16_t last_codepoint = 0;

   if (!oflags) {
      oflags = &oflags_s;
   }
   *oflags = 0;

#define UNESCAPE_BAIL(e, offset)                          \
   *err = JSONSL_ERROR_##e;                               \
   if (errat) {                                           \
      *errat = (const char *) (c + (ptrdiff_t) (offset)); \
   }                                                      \
   return 0;

   for (; len; len--, c++, out++) {
      int uescval;
      if (*c != '\\') {
         /* Not an escape, so we don't care about this */
         goto GT_ASSIGN;
      }

      if (len < 2) {
         UNESCAPE_BAIL (ESCAPE_INVALID, 0);
      }
      if (!is_allowed_escape (c[1])) {
         UNESCAPE_BAIL (ESCAPE_INVALID, 1)
      }
      if ((toEscape && toEscape[(unsigned char) c[1] & 0x7f] == 0 &&
           c[1] != '\\' && c[1] != '"')) {
         /* if we don't want to unescape this string, write the escape sequence
          * to the output */
         *out++ = *c++;
         if (--len == 0)
            break;
         goto GT_ASSIGN;
      }

      if (c[1] != 'u') {
         /* simple skip-and-replace using pre-defined maps.
          * TODO: should the maps actually reflect the desired
          * replacement character in toEscape?
          */
         char esctmp = get_escape_equiv (c[1]);
         if (esctmp) {
            /* Check if there is a corresponding replacement */
            *out = esctmp;
         } else {
            /* Just gobble up the 'reverse-solidus' */
            *out = c[1];
         }
         len--;
         c++;
         /* do not assign, just continue */
         continue;
      }

      /* next == 'u' */
      if (len < 6) {
         /* Need at least six characters.. */
         UNESCAPE_BAIL (UESCAPE_TOOSHORT, 2);
      }

      uescval = jsonsl__get_uescape_16 ((const char *) c + 2);
      if (uescval == -1) {
         UNESCAPE_BAIL (PERCENT_BADHEX, -1);
      }

      if (last_codepoint) {
         uint16_t w1 = last_codepoint, w2 = (uint16_t) uescval;
         uint32_t cp;

         if (uescval < 0xDC00 || uescval > 0xDFFF) {
            UNESCAPE_BAIL (INVALID_CODEPOINT, -1);
         }

         cp = (w1 & 0x3FF) << 10;
         cp |= (w2 & 0x3FF);
         cp += 0x10000;

         out = jsonsl__writeutf8 (cp, out) - 1;
         last_codepoint = 0;

      } else if (uescval < 0xD800 || uescval > 0xDFFF) {
         *oflags |= JSONSL_SPECIALf_NONASCII;
         out = jsonsl__writeutf8 (uescval, out) - 1;

      } else if (uescval > 0xD7FF && uescval < 0xDC00) {
         *oflags |= JSONSL_SPECIALf_NONASCII;
         last_codepoint = (uint16_t) uescval;
         out--;
      } else {
         UNESCAPE_BAIL (INVALID_CODEPOINT, 2);
      }

      /* Post uescape cleanup */
      len -= 5; /* Gobble up 5 chars after 'u' */
      c += 5;
      continue;

   /* Only reached by previous branches */
   GT_ASSIGN:
      *out = *c;
   }

   if (last_codepoint) {
      *err = JSONSL_ERROR_INVALID_CODEPOINT;
      return 0;
   }

   *err = JSONSL_ERROR_SUCCESS;
   return out - begin_p;
}

/**
 * Character Table definitions.
 * These were all generated via srcutil/genchartables.pl
 */

/**
 * This table contains the beginnings of non-string
 * allowable (bareword) values.
 */
static unsigned short Special_Table[0x100] = {
   /* 0x00 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0x1f */
   /* 0x20 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,                                         /* 0x2c */
   /* 0x2d */ JSONSL_SPECIALf_DASH /* <-> */, /* 0x2d */
   /* 0x2e */ 0,
   0,                                             /* 0x2f */
   /* 0x30 */ JSONSL_SPECIALf_ZERO /* <0> */,     /* 0x30 */
   /* 0x31 */ JSONSL_SPECIALf_UNSIGNED /* <1> */, /* 0x31 */
   /* 0x32 */ JSONSL_SPECIALf_UNSIGNED /* <2> */, /* 0x32 */
   /* 0x33 */ JSONSL_SPECIALf_UNSIGNED /* <3> */, /* 0x33 */
   /* 0x34 */ JSONSL_SPECIALf_UNSIGNED /* <4> */, /* 0x34 */
   /* 0x35 */ JSONSL_SPECIALf_UNSIGNED /* <5> */, /* 0x35 */
   /* 0x36 */ JSONSL_SPECIALf_UNSIGNED /* <6> */, /* 0x36 */
   /* 0x37 */ JSONSL_SPECIALf_UNSIGNED /* <7> */, /* 0x37 */
   /* 0x38 */ JSONSL_SPECIALf_UNSIGNED /* <8> */, /* 0x38 */
   /* 0x39 */ JSONSL_SPECIALf_UNSIGNED /* <9> */, /* 0x39 */
   /* 0x3a */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0x59 */
   /* 0x5a */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,                                          /* 0x65 */
   /* 0x66 */ JSONSL_SPECIALf_FALSE /* <f> */, /* 0x66 */
   /* 0x67 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,                                         /* 0x6d */
   /* 0x6e */ JSONSL_SPECIALf_NULL /* <n> */, /* 0x6e */
   /* 0x6f */ 0,
   0,
   0,
   0,
   0,                                         /* 0x73 */
   /* 0x74 */ JSONSL_SPECIALf_TRUE /* <t> */, /* 0x74 */
   /* 0x75 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0x94 */
   /* 0x95 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0xb4 */
   /* 0xb5 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0xd4 */
   /* 0xd5 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0xf4 */
   /* 0xf5 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0xfe */
};

/**
 * Contains characters which signal the termination of any of the 'special'
 * bareword
 * values.
 */
static int Special_Endings[0x100] = {
   /* 0x00 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,                        /* 0x08 */
   /* 0x09 */ 1 /* <TAB> */, /* 0x09 */
   /* 0x0a */ 1 /* <LF> */,  /* 0x0a */
   /* 0x0b */ 0,
   0,                       /* 0x0c */
   /* 0x0d */ 1 /* <CR> */, /* 0x0d */
   /* 0x0e */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,                       /* 0x1f */
   /* 0x20 */ 1 /* <SP> */, /* 0x20 */
   /* 0x21 */ 0,            /* 0x21 */
   /* 0x22 */ 1 /* " */,    /* 0x22 */
   /* 0x23 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,                    /* 0x2b */
   /* 0x2c */ 1 /* , */, /* 0x2c */
   /* 0x2d */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,                    /* 0x39 */
   /* 0x3a */ 1 /* : */, /* 0x3a */
   /* 0x3b */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,                    /* 0x5a */
   /* 0x5b */ 1 /* [ */, /* 0x5b */
   /* 0x5c */ 1 /* \ */, /* 0x5c */
   /* 0x5d */ 1 /* ] */, /* 0x5d */
   /* 0x5e */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,                    /* 0x7a */
   /* 0x7b */ 1 /* { */, /* 0x7b */
   /* 0x7c */ 0,         /* 0x7c */
   /* 0x7d */ 1 /* } */, /* 0x7d */
   /* 0x7e */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0x9d */
   /* 0x9e */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0xbd */
   /* 0xbe */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0xdd */
   /* 0xde */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,           /* 0xfd */
   /* 0xfe */ 0 /* 0xfe */
};

/**
 * This table contains entries for the allowed whitespace as per RFC 4627
 */
static int Allowed_Whitespace[0x100] = {
   /* 0x00 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,                        /* 0x08 */
   /* 0x09 */ 1 /* <TAB> */, /* 0x09 */
   /* 0x0a */ 1 /* <LF> */,  /* 0x0a */
   /* 0x0b */ 0,
   0,                       /* 0x0c */
   /* 0x0d */ 1 /* <CR> */, /* 0x0d */
   /* 0x0e */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,                       /* 0x1f */
   /* 0x20 */ 1 /* <SP> */, /* 0x20 */
   /* 0x21 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0x40 */
   /* 0x41 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0x60 */
   /* 0x61 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0x80 */
   /* 0x81 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0xa0 */
   /* 0xa1 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0xc0 */
   /* 0xc1 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0xe0 */
   /* 0xe1 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0 /* 0xfe */
};

static const int String_No_Passthrough[0x100] = {
   /* 0x00 */ 1 /* <NUL> */, /* 0x00 */
   /* 0x01 */ 1 /* <SOH> */, /* 0x01 */
   /* 0x02 */ 1 /* <STX> */, /* 0x02 */
   /* 0x03 */ 1 /* <ETX> */, /* 0x03 */
   /* 0x04 */ 1 /* <EOT> */, /* 0x04 */
   /* 0x05 */ 1 /* <ENQ> */, /* 0x05 */
   /* 0x06 */ 1 /* <ACK> */, /* 0x06 */
   /* 0x07 */ 1 /* <BEL> */, /* 0x07 */
   /* 0x08 */ 1 /* <BS> */,  /* 0x08 */
   /* 0x09 */ 1 /* <HT> */,  /* 0x09 */
   /* 0x0a */ 1 /* <LF> */,  /* 0x0a */
   /* 0x0b */ 1 /* <VT> */,  /* 0x0b */
   /* 0x0c */ 1 /* <FF> */,  /* 0x0c */
   /* 0x0d */ 1 /* <CR> */,  /* 0x0d */
   /* 0x0e */ 1 /* <SO> */,  /* 0x0e */
   /* 0x0f */ 1 /* <SI> */,  /* 0x0f */
   /* 0x10 */ 1 /* <DLE> */, /* 0x10 */
   /* 0x11 */ 1 /* <DC1> */, /* 0x11 */
   /* 0x12 */ 1 /* <DC2> */, /* 0x12 */
   /* 0x13 */ 1 /* <DC3> */, /* 0x13 */
   /* 0x14 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,                      /* 0x21 */
   /* 0x22 */ 1 /* <"> */, /* 0x22 */
   /* 0x23 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0x42 */
   /* 0x43 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,                      /* 0x5b */
   /* 0x5c */ 1 /* <\> */, /* 0x5c */
   /* 0x5d */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0x7c */
   /* 0x7d */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0x9c */
   /* 0x9d */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0xbc */
   /* 0xbd */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0xdc */
   /* 0xdd */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0xfc */
   /* 0xfd */ 0,
   0, /* 0xfe */
};

/**
 * Allowable two-character 'common' escapes:
 */
static int Allowed_Escapes[0x100] = {
   /* 0x00 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0x1f */
   /* 0x20 */ 0,
   0,                      /* 0x21 */
   /* 0x22 */ 1 /* <"> */, /* 0x22 */
   /* 0x23 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,                      /* 0x2e */
   /* 0x2f */ 1 /* </> */, /* 0x2f */
   /* 0x30 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0x4f */
   /* 0x50 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,                      /* 0x5b */
   /* 0x5c */ 1 /* <\> */, /* 0x5c */
   /* 0x5d */ 0,
   0,
   0,
   0,
   0,                      /* 0x61 */
   /* 0x62 */ 1 /* <b> */, /* 0x62 */
   /* 0x63 */ 0,
   0,
   0,                      /* 0x65 */
   /* 0x66 */ 1 /* <f> */, /* 0x66 */
   /* 0x67 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,                      /* 0x6d */
   /* 0x6e */ 1 /* <n> */, /* 0x6e */
   /* 0x6f */ 0,
   0,
   0,                      /* 0x71 */
   /* 0x72 */ 1 /* <r> */, /* 0x72 */
   /* 0x73 */ 0,           /* 0x73 */
   /* 0x74 */ 1 /* <t> */, /* 0x74 */
   /* 0x75 */ 1 /* <u> */, /* 0x75 */
   /* 0x76 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0x95 */
   /* 0x96 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0xb5 */
   /* 0xb6 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0xd5 */
   /* 0xd6 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0xf5 */
   /* 0xf6 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0xfe */
};

/**
 * This table contains the _values_ for a given (single) escaped character.
 */
static unsigned char Escape_Equivs[0x100] = {
   /* 0x00 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0x1f */
   /* 0x20 */ 0,
   0,
   34 /* <"> */,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0x3f */
   /* 0x40 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   92 /* <\> */,
   0,
   0,
   0, /* 0x5f */
   /* 0x60 */ 0,
   0,                      /* 0x61 */
   /* 0x62 */ 8 /* <b> */, /* 0x62 */
   /* 0x63 */ 0,
   0,
   0,                       /* 0x65 */
   /* 0x66 */ 12 /* <f> */, /* 0x66 */
   /* 0x67 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,                       /* 0x6d */
   /* 0x6e */ 10 /* <n> */, /* 0x6e */
   /* 0x6f */ 0,
   0,
   0,                       /* 0x71 */
   /* 0x72 */ 13 /* <r> */, /* 0x72 */
   /* 0x73 */ 0,            /* 0x73 */
   /* 0x74 */ 9 /* <t> */,  /* 0x74 */
   /* 0x75 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0x94 */
   /* 0x95 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0xb4 */
   /* 0xb5 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0xd4 */
   /* 0xd5 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0, /* 0xf4 */
   /* 0xf5 */ 0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0 /* 0xfe */
};

/* Definitions of above-declared static functions */
static char
get_escape_equiv (unsigned c)
{
   return Escape_Equivs[c & 0xff];
}
static unsigned
extract_special (unsigned c)
{
   return Special_Table[c & 0xff];
}
static int
is_special_end (unsigned c)
{
   return Special_Endings[c & 0xff];
}
static int
is_allowed_whitespace (unsigned c)
{
   return c == ' ' || Allowed_Whitespace[c & 0xff];
}
static int
is_allowed_escape (unsigned c)
{
   return Allowed_Escapes[c & 0xff];
}
static int
is_simple_char (unsigned c)
{
   return !String_No_Passthrough[c & 0xff];
}

/* Clean up all our macros! */
#undef INCR_METRIC
#undef INCR_GENERIC
#undef INCR_STRINGY_CATCH
#undef CASE_DIGITS
#undef INVOKE_ERROR
#undef STACK_PUSH
#undef STACK_POP_NOPOS
#undef STACK_POP
#undef CALLBACK_AND_POP_NOPOS
#undef CALLBACK_AND_POP
#undef SPECIAL_POP
#undef CUR_CHAR
#undef DO_CALLBACK
#undef ENSURE_HVAL
#undef VERIFY_SPECIAL
#undef STATE_SPECIAL_LENGTH
#undef IS_NORMAL_NUMBER
#undef STATE_NUM_LAST
#undef FASTPARSE_EXHAUSTED
#undef FASTPARSE_BREAK