name_code.c

[詳解]

/*++
/* NAME
/*  name_code 3
/* SUMMARY
/*  name to number table mapping
/* SYNOPSIS
/*  #include <name_code.h>
/*
/*  typedef struct {
/* .in +4
/*      const char *name;
/*      int code;
/* .in -4
/*  } NAME_CODE;
/*
/*  int name_code(table, flags, name)
/*  const NAME_CODE *table;
/*  int flags;
/*  const char *name;
/*
/*  const char *str_name_code(table, code)
/*  const NAME_CODE *table;
/*  int code;
/* DESCRIPTION
/*  This module does simple name<->number mapping. The process
/*  is controlled by a table of (name, code) values.
/*  The table is terminated with a null pointer and a code that
/*  corresponds to "name not found".
/*
/*  name_code() looks up the code that corresponds with the name.
/*  The lookup is case insensitive. The flags argument specifies
/*  zero or more of the following:
/* .IP NAME_CODE_FLAG_STRICT_CASE
/*  String lookups are case sensitive.
/* .PP
/*  For convenience the constant NAME_CODE_FLAG_NONE requests
/*  no special processing.
/*
/*  str_name_code() translates a number to its equivalent string.
/* DIAGNOSTICS
/*  When the search fails, the result is the "name not found" code
/*  or the null pointer, respectively.
/* LICENSE
/* .ad
/* .fi
/*  The Secure Mailer license must be distributed with this software.
/* AUTHOR(S)
/*  Wietse Venema
/*  IBM T.J. Watson Research
/*  P.O. Box 704
/*  Yorktown Heights, NY 10598, USA
/*--*/

/* System library. */

#include <sys_defs.h>
#include <string.h>

/* Utility library. */

#include <name_code.h>

/* name_code - look up code by name */

int     name_code(const NAME_CODE *table, int flags, const char *name)
{
    const NAME_CODE *np;
    int     (*lookup) (const char *, const char *);

    if (flags & NAME_CODE_FLAG_STRICT_CASE)
    lookup = strcmp;
    else
    lookup = strcasecmp;

    for (np = table; np->name; np++)
    if (lookup(name, np->name) == 0)
        break;
    return (np->code);
}

/* str_name_code - look up name by code */

const char *str_name_code(const NAME_CODE *table, int code)
{
    const NAME_CODE *np;

    for (np = table; np->name; np++)
    if (code == np->code)
        break;
    return (np->name);
}