midna_adomain.c

[詳解]

/*++
/* NAME
/*  midna_adomain 3
/* SUMMARY
/*  address domain part conversion
/* SYNOPSIS
/*  #include <midna_adomain.h>
/*
/*  char    *midna_adomain_to_ascii(
/*  VSTRING *dest,
/*  const char *name)
/*
/*  char    *midna_adomain_to_utf8(
/*  VSTRING *dest,
/*  const char *name)
/* DESCRIPTION
/*  The functions in this module transform the domain portion
/*  of an email address between ASCII and UTF-8 form.  Both
/*  functions tolerate a missing domain, and both functions
/*  return a copy of the input when the domain portion requires
/*  no conversion.
/*
/*  midna_adomain_to_ascii() converts an UTF-8 or ASCII domain
/*  portion to ASCII.  The result is a null pointer when
/*  conversion fails.  This function verifies that the resulting
/*  domain passes valid_hostname().
/*
/*  midna_adomain_to_utf8() converts an UTF-8 or ASCII domain
/*  name to UTF-8.  The result is a null pointer when conversion
/*  fails.  This function verifies that the resulting domain,
/*  after conversion to ASCII, passes valid_hostname().
/* SEE ALSO
/*  midna_domain(3), Postfix ASCII/UTF-8 domain name conversion
/* DIAGNOSTICS
/*  Fatal errors: memory allocation problem.
/*  Warnings: conversion error or result validation error.
/* 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>

#ifndef NO_EAI
#include <unicode/uidna.h>

 /*
  * Utility library.
  */
#include <vstring.h>
#include <stringops.h>
#include <midna_domain.h>

 /*
  * Global library.
  */
#include <midna_adomain.h>

#define STR(x)  vstring_str(x)

/* midna_adomain_to_utf8 - convert address domain portion to UTF8 */

char   *midna_adomain_to_utf8(VSTRING *dest, const char *src)
{
    const char *cp;
    const char *domain_utf8;

    if ((cp = strrchr(src, '@')) == 0) {
    vstring_strcpy(dest, src);
    } else {
    vstring_sprintf(dest, "%*s@", (int) (cp - src), src);
    if (*(cp += 1)) {
        if (allascii(cp) && strstr(cp, "--") == 0) {
        vstring_strcat(dest, cp);
        } else if ((domain_utf8 = midna_domain_to_utf8(cp)) == 0) {
        return (0);
        } else {
        vstring_strcat(dest, domain_utf8);
        }
    }
    }
    return (STR(dest));
}

/* midna_adomain_to_ascii - convert address domain portion to ASCII */

char   *midna_adomain_to_ascii(VSTRING *dest, const char *src)
{
    const char *cp;
    const char *domain_ascii;

    if ((cp = strrchr(src, '@')) == 0) {
    vstring_strcpy(dest, src);
    } else {
    vstring_sprintf(dest, "%*s@", (int) (cp - src), src);
    if (*(cp += 1)) {
        if (allascii(cp)) {
        vstring_strcat(dest, cp);
        } else if ((domain_ascii = midna_domain_to_ascii(cp + 1)) == 0) {
        return (0);
        } else {
        vstring_strcat(dest, domain_ascii);
        }
    }
    }
    return (STR(dest));
}

#endif                  /* NO_IDNA */