/* flex - tool to generate fast lexical analyzers */

/* SPDX-License-Identifier: BSD-3-Clause-flex */

/*  Copyright (c) 1990 The Regents of the University of California. */

/*  All rights reserved. */

/*  This code is derived from software contributed to Berkeley by */

/*  Vern Paxson. */

/*  The United States Government has rights in this work pursuant */

/*  to contract no. DE-AC03-76SF00098 between the United States */

/*  Department of Energy and the University of California. */

/*  This file is part of flex. */

/*  Redistribution and use in source and binary forms, with or without */

/*  modification, are permitted provided that the following conditions */

/*  are met: */

/*  1. Redistributions of source code must retain the above copyright */

/*     notice, this list of conditions and the following disclaimer. */

/*  2. Redistributions in binary form must reproduce the above copyright */

/*     notice, this list of conditions and the following disclaimer in the */

/*     documentation and/or other materials provided with the distribution. */

/*  Neither the name of the University nor the names of its contributors */

/*  may be used to endorse or promote products derived from this software */

/*  without specific prior written permission. */

/*  THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR */

/*  IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED */

/*  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR */

/*  PURPOSE. */

#include "flexdef.h"

#include "scanopt.h"

/* Internal structures */

#define ARG_NONE 0x01

#define ARG_REQ  0x02

#define ARG_OPT  0x04

#define IS_LONG  0x08

struct _aux {

  int     flags;    /* The above hex flags. */

  int     namelen;  /* Length of the actual option word, e.g., "--file[=foo]" is 4 */

  int     printlen; /* Length of entire string, e.g., "--file[=foo]" is 12 */

};

struct _scanopt_t {

  const optspec_t *options; /* List of options. */

  struct _aux *aux; /* Auxiliary data about options. */

  int     optc;   /* Number of options. */

  int     argc;   /* Number of args. */

  char  **argv;   /* Array of strings. */

  int     index;    /* Used as: argv[index][subscript]. */

  int     subscript;

  char    no_err_msg; /* If true, do not print errors. */

  char    has_long;

  char    has_short;

};

/* Accessor functions. These WOULD be one-liners, but portability calls. */

static const char *NAME(struct _scanopt_t *, int);

static int PRINTLEN(struct _scanopt_t *, int);

static int RVAL(struct _scanopt_t *, int);

static int FLAGS(struct _scanopt_t *, int);

static const char *DESC(struct _scanopt_t *, int);

static void scanopt_err(struct _scanopt_t *, int, int);

static int matchlongopt(char *, char **, int *, char **, int *);

static int find_opt(struct _scanopt_t *, int, char *, int, int *, int *opt_offset);

static const char *NAME (struct _scanopt_t *s, int i)

{

  return s->options[i].opt_fmt +

    ((s->aux[i].flags & IS_LONG) ? 2 : 1);

}

static int PRINTLEN (struct _scanopt_t *s, int i)

{

  return s->aux[i].printlen;

}

static int RVAL (struct _scanopt_t *s, int i)

{

  return s->options[i].r_val;

}

static int FLAGS (struct _scanopt_t *s, int i)

{

  return s->aux[i].flags;

}

static const char *DESC (struct _scanopt_t *s, int i)

{

  return s->options[i].desc ? s->options[i].desc : "";

}

#ifndef NO_SCANOPT_USAGE

static int get_cols (void);

static int get_cols (void)

{

  char   *env;

  int     cols = 80;  /* default */

#ifdef HAVE_NCURSES_H

  initscr ();

  endwin ();

  if (COLS > 0)

    return COLS;

#endif

  if ((env = getenv ("COLUMNS")) != NULL)

    cols = atoi (env);

  return cols;

}

#endif

/* Macro to check for NULL before assigning a value. */

#define SAFE_ASSIGN(ptr,val) \

    do{                      \

        if((ptr)!=NULL)      \

            *(ptr) = val;    \

    }while(0)

/* Macro to assure we reset subscript whenever we adjust s->index.*/

#define INC_INDEX(s,n)     \

    do{                    \

       (s)->index += (n);  \

       (s)->subscript= 0;  \

    }while(0)

scanopt_t *scanopt_init (const optspec_t *options, int argc, char **argv, int flags)

{

  int     i;

  struct _scanopt_t *s;

  s = malloc(sizeof (struct _scanopt_t));

  s->options = options;

  s->optc = 0;

  s->argc = argc;

  s->argv = (char **) argv;

  s->index = 1;

  s->subscript = 0;

  s->no_err_msg = (flags & SCANOPT_NO_ERR_MSG);

  s->has_long = 0;

  s->has_short = 0;

  /* Determine option count. (Find entry with all zeros). */

  s->optc = 0;

  while (options[s->optc].opt_fmt

         || options[s->optc].r_val || options[s->optc].desc)

    s->optc++;

  /* Build auxiliary data */

  s->aux = malloc((size_t) s->optc * sizeof (struct _aux));

  for (i = 0; i < s->optc; i++) {

    const unsigned char *p, *pname;

    const struct optspec_t *opt;

    struct _aux *aux;

    opt = s->options + i;

    aux = s->aux + i;

    aux->flags = ARG_NONE;

    if (opt->opt_fmt[0] == '-' && opt->opt_fmt[1] == '-') {

      aux->flags |= IS_LONG;

      pname = (const unsigned char *)(opt->opt_fmt + 2);

      s->has_long = 1;

    }

    else {

      pname = (const unsigned char *)(opt->opt_fmt + 1);

      s->has_short = 1;

    }

    aux->printlen = (int) strlen (opt->opt_fmt);

    aux->namelen = 0;

    for (p = pname + 1; *p; p++) {

      /* detect required arg */

      if (*p == '=' || isspace ((unsigned char)*p)

          || !(aux->flags & IS_LONG)) {

        if (aux->namelen == 0)

          aux->namelen = (int) (p - pname);

        aux->flags |= ARG_REQ;

        aux->flags &= ~ARG_NONE;

      }

      /* detect optional arg. This overrides required arg. */

      if (*p == '[') {

        if (aux->namelen == 0)

          aux->namelen = (int) (p - pname);

        aux->flags &= ~(ARG_REQ | ARG_NONE);

        aux->flags |= ARG_OPT;

        break;

      }

    }

    if (aux->namelen == 0)

      aux->namelen = (int) (p - pname);

  }

  return (scanopt_t *) s;

}

#ifndef NO_SCANOPT_USAGE

/* these structs are for scanopt_usage(). */

struct usg_elem {

  int     idx;

  struct usg_elem *next;

  struct usg_elem *alias;

};

typedef struct usg_elem usg_elem;

/* Prints a usage message based on contents of optlist.

 * Parameters:

 *   scanner  - The scanner, already initialized with scanopt_init().

 *   fp       - The file stream to write to.

 *   usage    - Text to be prepended to option list.

 * Return:  Always returns 0 (zero).

 * The output looks something like this:

[indent][option, alias1, alias2...][indent][description line1

                                            description line2...]

 */

int     scanopt_usage (scanopt_t *scanner, FILE *fp, const char *usage)

{

  struct _scanopt_t *s;

  int     i, columns;

  const int indent = 2;

  usg_elem *byr_val = NULL; /* option indices sorted by r_val */

  usg_elem *store;  /* array of preallocated elements. */

  int     store_idx = 0;

  usg_elem *ue;

  int     opt_col_width = 0, desc_col_width = 0;

  int     desccol;

  int     print_run = 0;

  s = (struct _scanopt_t *) scanner;

  if (usage) {

    fprintf (fp, "%s\n", usage);

  }

  else {

    fprintf (fp, _("Usage: %s [OPTIONS]...\n"), s->argv[0]);

  }

  fprintf (fp, "\n");

  /* Sort by r_val and string. Yes, this is O(n*n), but n is small. */

  store = malloc((size_t) s->optc * sizeof (usg_elem));

  for (i = 0; i < s->optc; i++) {

    /* grab the next preallocate node. */

    ue = store + store_idx++;

    ue->idx = i;

    ue->next = ue->alias = NULL;

    /* insert into list. */

    if (!byr_val)

      byr_val = ue;

    else {

      int     found_alias = 0;

      usg_elem **ue_curr, **ptr_if_no_alias = NULL;

      ue_curr = &byr_val;

      while (*ue_curr) {

        if (RVAL (s, (*ue_curr)->idx) ==

            RVAL (s, ue->idx)) {

          /* push onto the alias list. */

          ue_curr = &((*ue_curr)->alias);

          found_alias = 1;

          break;

        }

        if (!ptr_if_no_alias

            &&

            strcasecmp (NAME (s, (*ue_curr)->idx),

            NAME (s, ue->idx)) > 0) {

          ptr_if_no_alias = ue_curr;

        }

        ue_curr = &((*ue_curr)->next);

      }

      if (!found_alias && ptr_if_no_alias)

        ue_curr = ptr_if_no_alias;

      ue->next = *ue_curr;

      *ue_curr = ue;

    }

  }

#if 0

  if (1) {

    printf ("ORIGINAL:\n");

    for (i = 0; i < s->optc; i++)

      printf ("%2d: %s\n", i, NAME (s, i));

    printf ("SORTED:\n");

    ue = byr_val;

    while (ue) {

      usg_elem *ue2;

      printf ("%2d: %s\n", ue->idx, NAME (s, ue->idx));

      for (ue2 = ue->alias; ue2; ue2 = ue2->next)

        printf ("  +---> %2d: %s\n", ue2->idx,

          NAME (s, ue2->idx));

      ue = ue->next;

    }

  }

#endif

  /* Now build each row of output. */

  /* first pass calculate how much room we need. */

  for (ue = byr_val; ue; ue = ue->next) {

    usg_elem *ap;

    int     len;

    len = PRINTLEN(s, ue->idx);

    for (ap = ue->alias; ap; ap = ap->next) {

      len += PRINTLEN(s, ap->idx) + (int) strlen(", ");

    }

    if (len > opt_col_width)

      opt_col_width = len;

    /* It's much easier to calculate length for description column! */

    len = (int) strlen (DESC (s, ue->idx));

    if (len > desc_col_width)

      desc_col_width = len;

  }

  /* Determine how much room we have, and how much we will allocate to each col.

   * Do not address pathological cases. Output will just be ugly. */

  columns = get_cols () - 1;

  if (opt_col_width + desc_col_width + indent * 2 > columns) {

    /* opt col gets whatever it wants. we'll wrap the desc col. */

    desc_col_width = columns - (opt_col_width + indent * 2);

    if (desc_col_width < 14) /* 14 is arbitrary lower limit on desc width. */

      desc_col_width = INT_MAX;

  }

  desccol = opt_col_width + indent * 2;

#define PRINT_SPACES(fp,n) \

  fprintf((fp), "%*s", (n), "")

  /* Second pass (same as above loop), this time we print. */

  /* Sloppy hack: We iterate twice. The first time we print short and long options.

     The second time we print those lines that have ONLY long options. */

  while (print_run++ < 2) {

    for (ue = byr_val; ue; ue = ue->next) {

      usg_elem *ap;

      int     nwords = 0, nchars = 0, has_short = 0;

/* TODO: get has_short schtick to work */

      has_short = !(FLAGS (s, ue->idx) & IS_LONG);

      for (ap = ue->alias; ap; ap = ap->next) {

        if (!(FLAGS (s, ap->idx) & IS_LONG)) {

          has_short = 1;

          break;

        }

      }

      if ((print_run == 1 && !has_short) ||

          (print_run == 2 && has_short))

        continue;

      PRINT_SPACES (fp, indent);

      nchars += indent;

/* Print, adding a ", " between aliases. */

#define PRINT_IT(i) do{\

                  if(nwords++)\

                      nchars+=fprintf(fp,", ");\

                  nchars+=fprintf(fp,"%s",s->options[i].opt_fmt);\

            }while(0)

      if (!(FLAGS (s, ue->idx) & IS_LONG))

        PRINT_IT (ue->idx);

      /* print short aliases first. */

      for (ap = ue->alias; ap; ap = ap->next) {

        if (!(FLAGS (s, ap->idx) & IS_LONG))

          PRINT_IT (ap->idx);

      }

      if (FLAGS (s, ue->idx) & IS_LONG)

        PRINT_IT (ue->idx);

      /* repeat the above loop, this time for long aliases. */

      for (ap = ue->alias; ap; ap = ap->next) {

        if (FLAGS (s, ap->idx) & IS_LONG)

          PRINT_IT (ap->idx);

      }

      /* pad to desccol */

      PRINT_SPACES (fp, desccol - nchars);

      /* Print description, wrapped to desc_col_width columns. */

      if (1) {

        const char *pstart;

        pstart = DESC (s, ue->idx);

        while (1) {

          int     n = 0;

          const char *lastws = NULL, *p;

          p = pstart;

          while (*p && n < desc_col_width

                 && *p != '\n') {

            if (isspace ((unsigned char)(*p))

                || *p == '-') lastws =

                p;

            n++;

            p++;

          }

          if (!*p) { /* hit end of desc. done. */

            fprintf (fp, "%s\n",

               pstart);

            break;

          }

          else if (*p == '\n') { /* print everything up to here then wrap. */

            fprintf (fp, "%.*s\n", n,

               pstart);

            PRINT_SPACES (fp, desccol);

            pstart = p + 1;

            continue;

          }

          else { /* we hit the edge of the screen. wrap at space if possible. */

            if (lastws) {

              fprintf (fp,

                 "%.*s\n",

                 (int)(lastws - pstart),

                 pstart);

              pstart =

                lastws + 1;

            }

            else {

              fprintf (fp,

                 "%.*s\n",

                 n,

                 pstart);

              pstart = p + 1;

            }

            PRINT_SPACES (fp, desccol);

            continue;

          }

        }

      }

    }

  }     /* end while */

  free (store);

  return 0;

}

#endif /* no scanopt_usage */

static void scanopt_err(struct _scanopt_t *s, int is_short, int err)

{

  const char *optname = "";

  char    optchar[2];

  if (!s->no_err_msg) {

    if (s->index > 0 && s->index < s->argc) {

      if (is_short) {

        optchar[0] =

          s->argv[s->index][s->subscript];

        optchar[1] = '\0';

        optname = optchar;

      }

      else {

        optname = s->argv[s->index];

      }

    }

    fprintf (stderr, "%s: ", s->argv[0]);

    switch (err) {

    case SCANOPT_ERR_ARG_NOT_ALLOWED:

      fprintf (stderr,

         _

         ("option `%s' doesn't allow an argument\n"),

         optname);

      break;

    case SCANOPT_ERR_ARG_NOT_FOUND:

      fprintf (stderr,

         _("option `%s' requires an argument\n"),

         optname);

      break;

    case SCANOPT_ERR_OPT_AMBIGUOUS:

      fprintf (stderr, _("option `%s' is ambiguous\n"),

         optname);

      break;

    case SCANOPT_ERR_OPT_UNRECOGNIZED:

      fprintf (stderr, _("Unrecognized option `%s'\n"),

         optname);

      break;

    default:

      fprintf (stderr, _("Unknown error=(%d)\n"), err);

      break;

    }

  }

}

/* Internal. Match str against the regex  ^--([^=]+)(=(.*))?

 * return 1 if *looks* like a long option.

 * 'str' is the only input argument, the rest of the arguments are output only.

 * optname will point to str + 2

 *

 */

static int matchlongopt (char *str, char **optname, int *optlen, char **arg, int *arglen)

{

  char   *p;

  *optname = *arg = NULL;

  *optlen = *arglen = 0;

  /* Match regex /--./   */

  p = str;

  if (p[0] != '-' || p[1] != '-' || !p[2])

    return 0;

  p += 2;

  *optname = p;

  /* find the end of optname */

  while (*p && *p != '=')

    ++p;

  *optlen = (int) (p - *optname);

  if (!*p)

    /* an option with no '=...' part. */

    return 1;

  /* We saw an '=' char. The rest of p is the arg. */

  p++;

  *arg = p;

  while (*p)

    ++p;

  *arglen = (int) (p - *arg);

  return 1;

}

/* Internal. Look up long or short option by name.

 * Long options must match a non-ambiguous prefix, or exact match.

 * Short options must be exact.

 * Return boolean true if found and no error.

 * Error stored in err_code or zero if no error. */

static int find_opt (struct _scanopt_t *s, int lookup_long, char *optstart, int

  len, int *err_code, int *opt_offset)

{

  int     nmatch = 0, lastr_val = 0, i;

  *err_code = 0;

  *opt_offset = -1;

  if (!optstart)

    return 0;

  for (i = 0; i < s->optc; i++) {

    const char   *optname;

    optname = s->options[i].opt_fmt + (lookup_long ? 2 : 1);

    if (lookup_long && (s->aux[i].flags & IS_LONG)) {

      if (len > s->aux[i].namelen)

        continue;

      if (strncmp (optname, optstart, (size_t) len) == 0) {

        nmatch++;

        *opt_offset = i;

        /* exact match overrides all. */

        if (len == s->aux[i].namelen) {

          nmatch = 1;

          break;

        }

        /* ambiguity is ok between aliases. */

        if (lastr_val

            && lastr_val ==

            s->options[i].r_val) nmatch--;

        lastr_val = s->options[i].r_val;

      }

    }

    else if (!lookup_long && !(s->aux[i].flags & IS_LONG)) {

      if (optname[0] == optstart[0]) {

        nmatch++;

        *opt_offset = i;

      }

    }

  }

  if (nmatch == 0) {

    *err_code = SCANOPT_ERR_OPT_UNRECOGNIZED;

    *opt_offset = -1;

  }

  else if (nmatch > 1) {

    *err_code = SCANOPT_ERR_OPT_AMBIGUOUS;

    *opt_offset = -1;

  }

  return *err_code ? 0 : 1;

}

int     scanopt (scanopt_t *svoid, char **arg, int *optindex)

{

  char   *optname = NULL, *optarg = NULL, *pstart;

  int     namelen = 0, arglen = 0;

  int     errcode = 0, has_next;

  const optspec_t *optp;

  struct _scanopt_t *s;

  struct _aux *auxp;

  int     is_short;

  int     opt_offset = -1;

  s = (struct _scanopt_t *) svoid;

  /* Normalize return-parameters. */

  SAFE_ASSIGN (arg, NULL);

  SAFE_ASSIGN (optindex, s->index);

  if (s->index >= s->argc)

    return 0;

  /* pstart always points to the start of our current scan. */

  pstart = s->argv[s->index] + s->subscript;

  if (!pstart)

    return 0;

  if (s->subscript == 0) {

    /* test for exact match of "--" */

    if (pstart[0] == '-' && pstart[1] == '-' && !pstart[2]) {

      SAFE_ASSIGN (optindex, s->index + 1);

      INC_INDEX (s, 1);

      return 0;

    }

    /* Match an opt. */

    if (matchlongopt

        (pstart, &optname, &namelen, &optarg, &arglen)) {

      /* it LOOKS like an opt, but is it one?! */

      if (!find_opt

          (s, 1, optname, namelen, &errcode,

           &opt_offset)) {

        scanopt_err (s, 0, errcode);

        return errcode;

      }

      /* We handle this below. */

      is_short = 0;

      /* Check for short opt.  */

    }

    else if (pstart[0] == '-' && pstart[1]) {

      /* Pass through to below. */

      is_short = 1;

      s->subscript++;

      pstart++;

    }

    else {

      /* It's not an option. We're done. */

      return 0;

    }

  }

  /* We have to re-check the subscript status because it

   * may have changed above. */

  if (s->subscript != 0) {

    /* we are somewhere in a run of short opts,

     * e.g., at the 'z' in `tar -xzf` */

    optname = pstart;

    namelen = 1;

    is_short = 1;

    if (!find_opt

        (s, 0, pstart, namelen, &errcode, &opt_offset)) {

      scanopt_err(s, 1, errcode);

      return errcode;

    }

    optarg = pstart + 1;

    if (!*optarg) {

      optarg = NULL;

      arglen = 0;

    }

    else

      arglen = (int) strlen (optarg);

  }

  /* At this point, we have a long or short option matched at opt_offset into

   * the s->options array (and corresponding aux array).

   * A trailing argument is in {optarg,arglen}, if any.

   */

  /* Look ahead in argv[] to see if there is something

   * that we can use as an argument (if needed). */

  has_next = s->index + 1 < s->argc;

  optp = s->options + opt_offset;

  auxp = s->aux + opt_offset;

  /* case: no args allowed */

  if (auxp->flags & ARG_NONE) {

    if (optarg && !is_short) {

      scanopt_err(s, is_short, SCANOPT_ERR_ARG_NOT_ALLOWED);

      INC_INDEX (s, 1);

      return SCANOPT_ERR_ARG_NOT_ALLOWED;

    }

    else if (!optarg)

      INC_INDEX (s, 1);

    else

      s->subscript++;

    return optp->r_val;

  }

  /* case: required */

  if (auxp->flags & ARG_REQ) {

    if (!optarg && !has_next) {

      scanopt_err(s, is_short, SCANOPT_ERR_ARG_NOT_FOUND);

      return SCANOPT_ERR_ARG_NOT_FOUND;

    }

    if (!optarg) {

      /* Let the next argv element become the argument. */

      SAFE_ASSIGN (arg, s->argv[s->index + 1]);

      INC_INDEX (s, 2);

    }

    else {

      SAFE_ASSIGN (arg, (char *) optarg);

      INC_INDEX (s, 1);

    }

    return optp->r_val;

  }

  /* case: optional */

  if (auxp->flags & ARG_OPT) {

    SAFE_ASSIGN (arg, optarg);

    INC_INDEX (s, 1);

    return optp->r_val;

  }

  /* Should not reach here. */

  return 0;

}

int     scanopt_destroy (scanopt_t *svoid)

{

  struct _scanopt_t *s;

  s = (struct _scanopt_t *) svoid;

  if (s != NULL) {

    free(s->aux);

    free(s);

  }

  return 0;

}

/* vim:set tabstop=8 softtabstop=4 shiftwidth=4: */