dict_static.c

[詳解]

/*++
/* NAME
/*  dict_static 3
/* SUMMARY
/*  dictionary manager interface to static variables
/* SYNOPSIS
/*  #include <dict_static.h>
/*
/*  DICT    *dict_static_open(name, name, dict_flags)
/*  const char *name;
/*  int dummy;
/*  int dict_flags;
/* DESCRIPTION
/*  dict_static_open() implements a dummy dictionary that returns
/*  as lookup result the dictionary name, regardless of the lookup
/*  key value.
/* SEE ALSO
/*  dict(3) generic dictionary manager
/* LICENSE
/* .ad
/* .fi
/*  The Secure Mailer license must be distributed with this software.
/* AUTHOR(S)
/*  jeffm
/*  ghostgun.com
/*--*/

/* System library. */

#include "sys_defs.h"
#include <stdio.h>          /* sprintf() prototype */
#include <stdlib.h>
#include <unistd.h>
#include <string.h>

/* Utility library. */

#include "mymalloc.h"
#include "msg.h"
#include "stringops.h"
#include "dict.h"
#include "dict_static.h"

/* dict_static_lookup - access static value*/

static const char *dict_static_lookup(DICT *dict, const char *unused_name)
{
    DICT_ERR_VAL_RETURN(dict, DICT_ERR_NONE, dict->name);
}

/* dict_static_close - close static dictionary */

static void dict_static_close(DICT *dict)
{
    dict_free(dict);
}

/* dict_static_open - make association with static variable */

DICT   *dict_static_open(const char *name, int open_flags, int dict_flags)
{
    DICT   *dict;
    char   *err = 0;
    char   *cp, *saved_name = 0;

    /*
     * Let the optimizer worry about eliminating redundant code.
     */
#define DICT_STATIC_OPEN_RETURN(d) do { \
        DICT *__d = (d); \
        if (saved_name != 0) \
            myfree(saved_name); \
        if (err != 0) \
            myfree(err); \
        return (__d); \
    } while (0)

    /*
     * Optionally strip surrounding braces and whitespace.
     */
    if (name[0] == CHARS_BRACE[0]) {
    saved_name = cp = mystrdup(name);
    if ((err = extpar(&cp, CHARS_BRACE, EXTPAR_FLAG_STRIP)) != 0)
        DICT_STATIC_OPEN_RETURN(dict_surrogate(DICT_TYPE_STATIC, name,
                           open_flags, dict_flags,
                           "bad %s:name syntax: %s",
                           DICT_TYPE_STATIC, err));
    name = cp;
    }

    /*
     * Bundle up the request.
     */
    dict = dict_alloc(DICT_TYPE_STATIC, name, sizeof(*dict));
    dict->lookup = dict_static_lookup;
    dict->close = dict_static_close;
    dict->flags = dict_flags | DICT_FLAG_FIXED;
    dict->owner.status = DICT_OWNER_TRUSTED;
    DICT_STATIC_OPEN_RETURN(DICT_DEBUG (dict));
}