path: root/camel/camel-mime-part.c

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8; fill-column: 160 -*- */
/* camelMimePart.c : Abstract class for a mime_part */

/* 
 * Authors: Bertrand Guiheneuf <bertrand@helixcode.com>
 *      Michael Zucchi <notzed@ximian.com>
 *
 * Copyright 1999, 2000 Ximian, Inc. (www.ximian.com)
 *
 * This program is free software; you can redistribute it and/or 
 * modify it under the terms of version 2 of the GNU General Public 
 * License as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
 * USA
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <string.h>
#include <stdio.h>
#include <ctype.h>

#include <errno.h>

#include <gal/util/e-iconv.h>

#include "hash-table-utils.h"
#include "camel-mime-parser.h"
#include "camel-stream-mem.h"
#include "camel-stream-filter.h"
#include "camel-mime-filter-basic.h"
#include "camel-mime-filter-crlf.h"
#include "camel-mime-filter-charset.h"
#include "camel-mime-part.h"
#include "camel-mime-part-utils.h"
#include "camel-exception.h"
#include "camel-charset-map.h"
#include "string-utils.h"

#define d(x) /*(printf("%s(%d): ", __FILE__, __LINE__),(x))*/

typedef enum {
    HEADER_UNKNOWN,
    HEADER_DESCRIPTION,
    HEADER_DISPOSITION,
    HEADER_CONTENT_ID,
    HEADER_ENCODING,
    HEADER_CONTENT_MD5,
    HEADER_CONTENT_LOCATION,
    HEADER_CONTENT_LANGUAGES,
    HEADER_CONTENT_TYPE
} CamelHeaderType;


static GHashTable *header_name_table;
static GHashTable *header_formatted_table;

static CamelMediumClass *parent_class=NULL;

/* Returns the class for a CamelMimePart */
#define CMP_CLASS(so) CAMEL_MIME_PART_CLASS (CAMEL_OBJECT_GET_CLASS(so))
#define CDW_CLASS(so) CAMEL_DATA_WRAPPER_CLASS (CAMEL_OBJECT_GET_CLASS(so))
#define CMD_CLASS(so) CAMEL_MEDIUM_CLASS (CAMEL_OBJECT_GET_CLASS(so))

/* from CamelDataWrapper */
static int             write_to_stream                 (CamelDataWrapper *data_wrapper, CamelStream *stream);
static int         construct_from_stream           (CamelDataWrapper *dw, CamelStream *s);

/* from CamelMedia */ 
static void            add_header                      (CamelMedium *medium, const char *header_name, const void *header_value);
static void            set_header                      (CamelMedium *medium, const char *header_name, const void *header_value);
static void            remove_header                   (CamelMedium *medium, const char *header_name);
static const void     *get_header                      (CamelMedium *medium, const char *header_name);
static GArray         *get_headers                     (CamelMedium *medium);
static void            free_headers                    (CamelMedium *medium, GArray *headers);

static void            set_content_object              (CamelMedium *medium, CamelDataWrapper *content);

/* from camel mime parser */
static int             construct_from_parser           (CamelMimePart *, CamelMimeParser *);

/* forward references */
static void set_disposition (CamelMimePart *mime_part, const gchar *disposition);


/* loads in a hash table the set of header names we */
/* recognize and associate them with a unique enum  */
/* identifier (see CamelHeaderType above)           */
static void
init_header_name_table()
{
    header_name_table = g_hash_table_new (g_strcase_hash, g_strcase_equal);
    g_hash_table_insert (header_name_table, "Content-Description", (gpointer)HEADER_DESCRIPTION);
    g_hash_table_insert (header_name_table, "Content-Disposition", (gpointer)HEADER_DISPOSITION);
    g_hash_table_insert (header_name_table, "Content-id", (gpointer)HEADER_CONTENT_ID);
    g_hash_table_insert (header_name_table, "Content-Transfer-Encoding", (gpointer)HEADER_ENCODING);
    g_hash_table_insert (header_name_table, "Content-MD5", (gpointer)HEADER_CONTENT_MD5);
    g_hash_table_insert (header_name_table, "Content-Location", (gpointer)HEADER_CONTENT_LOCATION);
    g_hash_table_insert (header_name_table, "Content-Type", (gpointer)HEADER_CONTENT_TYPE);

    header_formatted_table = g_hash_table_new(g_strcase_hash, g_strcase_equal);
    g_hash_table_insert(header_formatted_table, "Content-Type", (void *)1);
    g_hash_table_insert(header_formatted_table, "Content-Disposition", (void *)1);
    g_hash_table_insert(header_formatted_table, "To", (void *)1);
    g_hash_table_insert(header_formatted_table, "From", (void *)1);
    g_hash_table_insert(header_formatted_table, "Reply-To", (void *)1);
    g_hash_table_insert(header_formatted_table, "Cc", (void *)1);
    g_hash_table_insert(header_formatted_table, "Bcc", (void *)1);
    g_hash_table_insert(header_formatted_table, "Message-ID", (void *)1);
}

static void
camel_mime_part_class_init (CamelMimePartClass *camel_mime_part_class)
{
    CamelMediumClass *camel_medium_class = CAMEL_MEDIUM_CLASS (camel_mime_part_class);
    CamelDataWrapperClass *camel_data_wrapper_class = CAMEL_DATA_WRAPPER_CLASS (camel_mime_part_class);

    parent_class = CAMEL_MEDIUM_CLASS (camel_type_get_global_classfuncs (camel_medium_get_type ()));
    init_header_name_table();

    camel_mime_part_class->construct_from_parser = construct_from_parser;
    
    /* virtual method overload */   
    camel_medium_class->add_header                = add_header;
    camel_medium_class->set_header                = set_header;
    camel_medium_class->get_header                = get_header;
    camel_medium_class->remove_header             = remove_header;
    camel_medium_class->get_headers               = get_headers;
    camel_medium_class->free_headers              = free_headers;
    camel_medium_class->set_content_object        = set_content_object;

    camel_data_wrapper_class->write_to_stream     = write_to_stream;
    camel_data_wrapper_class->construct_from_stream= construct_from_stream;
}

static void
camel_mime_part_init (gpointer   object,  gpointer   klass)
{
    CamelMimePart *camel_mime_part = CAMEL_MIME_PART (object);
    
    camel_mime_part->content_type         = header_content_type_new ("text", "plain");
    camel_mime_part->description          = NULL;
    camel_mime_part->disposition          = NULL;
    camel_mime_part->content_id           = NULL;
    camel_mime_part->content_MD5          = NULL;
    camel_mime_part->content_location     = NULL;
    camel_mime_part->content_languages    = NULL;
    camel_mime_part->encoding             = CAMEL_MIME_PART_ENCODING_DEFAULT;
}


static void           
camel_mime_part_finalize (CamelObject *object)
{
    CamelMimePart *mime_part = CAMEL_MIME_PART (object);

    g_free (mime_part->description);
    g_free (mime_part->content_id);
    g_free (mime_part->content_MD5);
    g_free (mime_part->content_location);
    string_list_free (mime_part->content_languages);
    header_disposition_unref(mime_part->disposition);
    
    if (mime_part->content_type)
        header_content_type_unref (mime_part->content_type);

    header_raw_clear(&mime_part->headers);
}



CamelType
camel_mime_part_get_type (void)
{
    static CamelType camel_mime_part_type = CAMEL_INVALID_TYPE;
    
    if (camel_mime_part_type == CAMEL_INVALID_TYPE) {
        camel_mime_part_type = camel_type_register (CAMEL_MEDIUM_TYPE, "CamelMimePart",
                                sizeof (CamelMimePart),
                                sizeof (CamelMimePartClass),
                                (CamelObjectClassInitFunc) camel_mime_part_class_init,
                                NULL,
                                (CamelObjectInitFunc) camel_mime_part_init,
                                (CamelObjectFinalizeFunc) camel_mime_part_finalize);
    }
    
    return camel_mime_part_type;
}


/* **** */

static gboolean
process_header(CamelMedium *medium, const char *header_name, const char *header_value)
{
    CamelMimePart *mime_part = CAMEL_MIME_PART (medium);
    CamelHeaderType header_type;
    const char *charset;
    char *text;

    /* Try to parse the header pair. If it corresponds to something   */
    /* known, the job is done in the parsing routine. If not,         */
    /* we simply add the header in a raw fashion                      */

    header_type = (CamelHeaderType) g_hash_table_lookup (header_name_table, header_name);
    switch (header_type) {
    case HEADER_DESCRIPTION: /* raw header->utf8 conversion */
        g_free (mime_part->description);
        if (mime_part->content_type)
            charset = e_iconv_charset_name(header_content_type_param(mime_part->content_type, "charset"));
        else
            charset = NULL;
        mime_part->description = g_strstrip (header_decode_string (header_value, charset));
        break;
    case HEADER_DISPOSITION:
        set_disposition (mime_part, header_value);
        break;
    case HEADER_CONTENT_ID:
        g_free (mime_part->content_id);
        mime_part->content_id = header_msgid_decode (header_value);
        break;
    case HEADER_ENCODING:
        text = header_token_decode (header_value);
        mime_part->encoding = camel_mime_part_encoding_from_string (text);
        g_free (text);
        break;
    case HEADER_CONTENT_MD5:
        g_free (mime_part->content_MD5);
        mime_part->content_MD5 = g_strdup (header_value);
        break;
    case HEADER_CONTENT_LOCATION:
        g_free (mime_part->content_location);
        mime_part->content_location = header_location_decode (header_value);
        break;
    case HEADER_CONTENT_TYPE: 
        if (mime_part->content_type)
            header_content_type_unref (mime_part->content_type);
        mime_part->content_type = header_content_type_decode (header_value);
        break;
    default:
        return FALSE;
    }
    return TRUE;
}

static void
set_header (CamelMedium *medium, const char *header_name, const void *header_value)
{
    CamelMimePart *part = CAMEL_MIME_PART (medium);
    
    process_header(medium, header_name, header_value);
    header_raw_replace(&part->headers, header_name, header_value, -1);
}

static void
add_header (CamelMedium *medium, const char *header_name, const void *header_value)
{
    CamelMimePart *part = CAMEL_MIME_PART (medium);
    
    /* Try to parse the header pair. If it corresponds to something   */
    /* known, the job is done in the parsing routine. If not,         */
    /* we simply add the header in a raw fashion                      */

    /* If it was one of the headers we handled, it must be unique, set it instead of add */
    if (process_header(medium, header_name, header_value))
        header_raw_replace(&part->headers, header_name, header_value, -1);
    else
        header_raw_append(&part->headers, header_name, header_value, -1);
}

static void
remove_header (CamelMedium *medium, const char *header_name)
{
    CamelMimePart *part = (CamelMimePart *)medium;
    
    process_header(medium, header_name, NULL);
    header_raw_remove(&part->headers, header_name);
}

static const void *
get_header (CamelMedium *medium, const char *header_name)
{
    CamelMimePart *part = (CamelMimePart *)medium;

    return header_raw_find(&part->headers, header_name, NULL);
}

static GArray *
get_headers (CamelMedium *medium)
{
    CamelMimePart *part = (CamelMimePart *)medium;
    GArray *headers;
    CamelMediumHeader header;
    struct _header_raw *h;

    headers = g_array_new (FALSE, FALSE, sizeof (CamelMediumHeader));
    for (h = part->headers; h; h = h->next) {
        header.name = h->name;
        header.value = h->value;
        g_array_append_val (headers, header);
    }

    return headers;
}

static void
free_headers (CamelMedium *medium, GArray *gheaders)
{
    g_array_free (gheaders, TRUE);
}

/* **** Content-Description */
void
camel_mime_part_set_description (CamelMimePart *mime_part, const gchar *description)
{
    char *text = header_encode_string (description);
    
    camel_medium_set_header (CAMEL_MEDIUM (mime_part),
                 "Content-Description", text);
    g_free (text);
}

const gchar *
camel_mime_part_get_description (CamelMimePart *mime_part)
{
    return mime_part->description;
}

/* **** Content-Disposition */

static void
set_disposition (CamelMimePart *mime_part, const gchar *disposition)
{
    header_disposition_unref(mime_part->disposition);
    if (disposition)
        mime_part->disposition = header_disposition_decode(disposition);
    else
        mime_part->disposition = NULL;
}


void
camel_mime_part_set_disposition (CamelMimePart *mime_part, const gchar *disposition)
{
    char *text;

    /* we poke in a new disposition (so we dont lose 'filename', etc) */
    if (mime_part->disposition == NULL) {
        set_disposition(mime_part, disposition);
    }
    if (mime_part->disposition != NULL) {
        g_free(mime_part->disposition->disposition);
        mime_part->disposition->disposition = g_strdup(disposition);
    }
    text = header_disposition_format(mime_part->disposition);

    camel_medium_set_header (CAMEL_MEDIUM (mime_part),
                 "Content-Disposition", text);

    g_free(text);
}

const gchar *
camel_mime_part_get_disposition (CamelMimePart *mime_part)
{
    if (mime_part->disposition)
        return (mime_part->disposition)->disposition;
    else
        return NULL;
}


/* **** Content-Disposition: filename="xxx" */

void
camel_mime_part_set_filename (CamelMimePart *mime_part, const gchar *filename)
{
    char *str;
    if (mime_part->disposition == NULL)
        mime_part->disposition = header_disposition_decode("attachment");

    header_set_param(&mime_part->disposition->params, "filename", filename);
    str = header_disposition_format(mime_part->disposition);

    camel_medium_set_header (CAMEL_MEDIUM (mime_part),
                 "Content-Disposition", str);
    g_free(str);
}

const gchar *
camel_mime_part_get_filename (CamelMimePart *mime_part)
{
    if (mime_part->disposition) {
        const gchar *name = header_param (mime_part->disposition->params, "filename");
        if (name)
            return name;
    }

    return header_content_type_param (mime_part->content_type, "name");
}


/* **** Content-ID: */

void
camel_mime_part_set_content_id (CamelMimePart *mime_part, const char *contentid)
{
    char *cid, *id;
    
    if (contentid)
        id = g_strstrip (g_strdup (contentid));
    else
        id = header_msgid_generate ();
    
    cid = g_strdup_printf ("<%s>", id);
    g_free (id);
    camel_medium_set_header (CAMEL_MEDIUM (mime_part), "Content-ID", cid);
    g_free (cid);
}

const gchar *
camel_mime_part_get_content_id (CamelMimePart *mime_part)
{
    return mime_part->content_id;
}

/* **** Content-MD5: */

void
camel_mime_part_set_content_MD5 (CamelMimePart *mime_part, const char *md5)
{
    camel_medium_set_header (CAMEL_MEDIUM (mime_part), "Content-MD5", md5);
}

const gchar *
camel_mime_part_get_content_MD5 (CamelMimePart *mime_part)
{
    return mime_part->content_MD5;
}

/* **** Content-MD5: */

void
camel_mime_part_set_content_location (CamelMimePart *mime_part, const char *location)
{
    camel_medium_set_header (CAMEL_MEDIUM (mime_part), "Content-Location", location);
}

const gchar *
camel_mime_part_get_content_location (CamelMimePart *mime_part)
{
    return mime_part->content_location;
}

/* **** Content-Transfer-Encoding: */

void
camel_mime_part_set_encoding (CamelMimePart *mime_part,
                  CamelMimePartEncodingType encoding)
{
    const char *text;

    text = camel_mime_part_encoding_to_string (encoding);
    camel_medium_set_header (CAMEL_MEDIUM (mime_part),
                 "Content-Transfer-Encoding", text);
}

const CamelMimePartEncodingType
camel_mime_part_get_encoding (CamelMimePart *mime_part)
{
    return mime_part->encoding;
}

/* FIXME: do something with this stuff ... */

void
camel_mime_part_set_content_languages (CamelMimePart *mime_part, GList *content_languages)
{
    if (mime_part->content_languages) string_list_free (mime_part->content_languages);
    mime_part->content_languages = content_languages;

    /* FIXME: translate to a header and set it */
}

const GList *
camel_mime_part_get_content_languages (CamelMimePart *mime_part)
{
    return mime_part->content_languages;
}


/* **** */

/* **** Content-Type: */

void 
camel_mime_part_set_content_type (CamelMimePart *mime_part, gchar *content_type)
{
    camel_medium_set_header (CAMEL_MEDIUM (mime_part),
                 "Content-Type", content_type);
}

CamelContentType *
camel_mime_part_get_content_type (CamelMimePart *mime_part)
{
    return mime_part->content_type;
}

/*********/



static void
set_content_object (CamelMedium *medium, CamelDataWrapper *content)
{
    CamelMimePart *mime_part = CAMEL_MIME_PART (medium);
    CamelContentType *object_content_type;

    parent_class->set_content_object (medium, content);

    object_content_type = camel_data_wrapper_get_mime_type_field (content);
    if (mime_part->content_type != object_content_type) {
        char *txt;

        txt = header_content_type_format (object_content_type);
        camel_medium_set_header (CAMEL_MEDIUM (mime_part), "Content-Type", txt);
        g_free(txt);
    }
}

/**********************************************************************/

static int
write_to_stream(CamelDataWrapper *data_wrapper, CamelStream *stream)
{
    CamelMimePart *mp = CAMEL_MIME_PART(data_wrapper);
    CamelMedium *medium = CAMEL_MEDIUM(data_wrapper);
    CamelStream *ostream = stream;
    CamelDataWrapper *content;
    int total = 0;
    int count;

    d(printf("mime_part::write_to_stream\n"));

    /* FIXME: something needs to be done about this ... */
    /* FIXME: need to count these bytes too */
#ifndef NO_WARNINGS
#warning content-languages should be stored as a header
#endif
    
    if (mp->headers) {
        struct _header_raw *h = mp->headers;
        char *val;
        
        /* fold/write the headers.   But dont fold headers that are already formatted
           (e.g. ones with parameter-lists, that we know about, and have created) */
        while (h) {
            val = h->value;
            if (val == NULL) {
                g_warning("h->value is NULL here for %s", h->name);
                count = 0;
            } else if (g_hash_table_lookup(header_formatted_table, h->name) == NULL) {
                val = header_fold(val, strlen(h->name));
                count = camel_stream_printf(stream, "%s%s%s\n", h->name, isspace(val[0]) ? ":" : ": ", val);
                g_free(val);
            } else {
                count = camel_stream_printf(stream, "%s%s%s\n", h->name, isspace(val[0]) ? ":" : ": ", val);
            }
            if (count == -1)
                return -1;
            total += count;
            h = h->next;
        }
    }
    
    count = camel_stream_write(stream, "\n", 1);
    if (count == -1)
        return -1;
    total += count;
    
    content = camel_medium_get_content_object(medium);
    if (content) {
        /* I dont really like this here, but i dont know where else it might go ... */
#define CAN_THIS_GO_ELSEWHERE
#ifdef CAN_THIS_GO_ELSEWHERE
        CamelMimeFilter *filter = NULL;
        CamelStreamFilter *filter_stream = NULL;
        CamelMimeFilter *charenc = NULL;
        const char *filename;
        const char *charset;
        
        switch (mp->encoding) {
        case CAMEL_MIME_PART_ENCODING_BASE64:
            filter = (CamelMimeFilter *)camel_mime_filter_basic_new_type(CAMEL_MIME_FILTER_BASIC_BASE64_ENC);
            break;
        case CAMEL_MIME_PART_ENCODING_QUOTEDPRINTABLE:
            filter = (CamelMimeFilter *)camel_mime_filter_basic_new_type(CAMEL_MIME_FILTER_BASIC_QP_ENC);
            break;
        case CAMEL_MIME_PART_ENCODING_UUENCODE:
            filename = camel_mime_part_get_filename (mp);
            count = camel_stream_printf (ostream, "begin 644 %s\n", filename ? filename : "untitled");
            if (count == -1)
                return -1;
            total += count;
            filter = (CamelMimeFilter *)camel_mime_filter_basic_new_type(CAMEL_MIME_FILTER_BASIC_UU_ENC);
            break;
        default:
            break;
        }
        
        if (!data_wrapper->rawtext && header_content_type_is(mp->content_type, "text", "*")) {
            charset = header_content_type_param(mp->content_type, "charset");
            if (charset && !(!strcasecmp(charset, "us-ascii") || !strcasecmp(charset, "utf-8"))) {
                charenc = (CamelMimeFilter *)camel_mime_filter_charset_new_convert("UTF-8", charset);
            } 
        }
        
        if (filter || charenc) {
            filter_stream = camel_stream_filter_new_with_stream(stream);
            
            /* if we have a character encoder, add that always */
            if (charenc) {
                camel_stream_filter_add(filter_stream, charenc);
                camel_object_unref((CamelObject *)charenc);
            }
            
            /* we only re-do crlf on encoded blocks */
            if (filter && header_content_type_is(mp->content_type, "text", "*")) {
                CamelMimeFilter *crlf = camel_mime_filter_crlf_new(CAMEL_MIME_FILTER_CRLF_ENCODE,
                                           CAMEL_MIME_FILTER_CRLF_MODE_CRLF_ONLY);
                
                camel_stream_filter_add(filter_stream, crlf);
                camel_object_unref((CamelObject *)crlf);
            }
            
            if (filter) {
                camel_stream_filter_add(filter_stream, filter);
                camel_object_unref((CamelObject *)filter);
            }
            
            stream = (CamelStream *)filter_stream;
        }

#endif
        
        count = camel_data_wrapper_write_to_stream(content, stream);
        
        if (filter_stream) {
            camel_stream_flush((CamelStream *)filter_stream);
            camel_object_unref((CamelObject *)filter_stream);
        }
        if (count == -1)
            return -1;
        total += count;
        
        if (mp->encoding == CAMEL_MIME_PART_ENCODING_UUENCODE) {
            count = camel_stream_write (ostream, "end\n", 4);
            if (count == -1)
                return -1;
            total += count;
        }
    } else {
        g_warning("No content for medium, nothing to write");
    }
    
    return total;
}

/* mime_part */
static int
construct_from_parser(CamelMimePart *dw, CamelMimeParser *mp)
{
    struct _header_raw *headers;
    const char *content;
    char *buf;
    int len;
    int err;

    d(printf("mime_part::construct_from_parser()\n"));

    switch (camel_mime_parser_step(mp, &buf, &len)) {
    case HSCAN_MESSAGE:
        /* set the default type of a message always */
        if (dw->content_type)
            header_content_type_unref (dw->content_type);
        dw->content_type = header_content_type_decode ("message/rfc822");
    case HSCAN_HEADER:
    case HSCAN_MULTIPART:
        /* we have the headers, build them into 'us' */
        headers = camel_mime_parser_headers_raw(mp);

        /* if content-type exists, process it first, set for fallback charset in headers */
        content = header_raw_find(&headers, "content-type", NULL);
        if (content)
            process_header((CamelMedium *)dw, "content-type", content);

        while (headers) {
            camel_medium_add_header((CamelMedium *)dw, headers->name, headers->value);
            headers = headers->next;
        }
        camel_mime_part_construct_content_from_parser(dw, mp);
        break;
    default:
        g_warning("Invalid state encountered???: %d", camel_mime_parser_state(mp));
    }

    d(printf("mime_part::construct_from_parser() leaving\n"));
#ifndef NO_WARNINGS
#warning "Need to work out how to detect a (fatally) bad parse in the parser"
#endif

    err = camel_mime_parser_errno(mp);
    if (err != 0) {
        errno = err;
        return -1;
    }

    return 0;
}

/**
 * camel_mime_part_construct_from_parser:
 * @mime_part: 
 * @mp: 
 * 
 * 
 * 
 * Return value: 
 **/
int
camel_mime_part_construct_from_parser(CamelMimePart *mime_part, CamelMimeParser *mp)
{
    return CMP_CLASS (mime_part)->construct_from_parser (mime_part, mp);
}

static int
construct_from_stream(CamelDataWrapper *dw, CamelStream *s)
{
    CamelMimeParser *mp;
    int ret;

    d(printf("mime_part::construct_from_stream()\n"));

    mp = camel_mime_parser_new();
    if (camel_mime_parser_init_with_stream(mp, s) == -1) {
        g_warning("Cannot create parser for stream");
        ret = -1;
    } else {
        ret = camel_mime_part_construct_from_parser((CamelMimePart *)dw, mp);
    }
    camel_object_unref((CamelObject *)mp);
    return ret;
}

/* this must be kept in sync with the header */
static const char *encodings[] = {
    "",
    "7bit",
    "8bit",
    "base64",
    "quoted-printable",
    "binary",
    "x-uuencode",
};

const char *
camel_mime_part_encoding_to_string (CamelMimePartEncodingType encoding)
{
    if (encoding >= sizeof(encodings)/sizeof(encodings[0]))
        encoding = 0;

    return encodings[encoding];
}

/* FIXME I am not sure this is the correct way to do this.  */
CamelMimePartEncodingType
camel_mime_part_encoding_from_string (const gchar *string)
{
    int i;

    if (string != NULL) {
        for (i=0;i<sizeof(encodings)/sizeof(encodings[0]);i++)
            if (!strcasecmp(string, encodings[i]))
                return i;
    }

    return CAMEL_MIME_PART_ENCODING_DEFAULT;
}


/******************************/
/**  Misc utility functions  **/

/**
 * camel_mime_part_new:
 *
 * Return value: a new CamelMimePart
 **/
CamelMimePart *
camel_mime_part_new (void)
{
    return (CamelMimePart *)camel_object_new (CAMEL_MIME_PART_TYPE);
}

/**
 * camel_mime_part_set_content:
 * @camel_mime_part: Mime part
 * @data: data to put into the part
 * @length: length of @data
 * @type: Content-Type of the data
 * 
 * Utility function used to set the content of a mime part object to 
 * be the provided data. If @length is 0, this routine can be used as
 * a way to remove old content (in which case @data and @type are
 * ignored and may be %NULL).
 **/
void 
camel_mime_part_set_content (CamelMimePart *camel_mime_part,
                 const char *data, int length,
                 const char *type) /* why on earth is the type last? */
{
    CamelMedium *medium = CAMEL_MEDIUM (camel_mime_part);

    if (length) {
        CamelDataWrapper *dw;
        CamelStream *stream;

        dw = camel_data_wrapper_new ();
        camel_data_wrapper_set_mime_type (dw, type);
        stream = camel_stream_mem_new_with_buffer (data, length);
        camel_data_wrapper_construct_from_stream (dw, stream);
        camel_object_unref (CAMEL_OBJECT (stream));
        camel_medium_set_content_object (medium, dw);
        camel_object_unref (CAMEL_OBJECT (dw));
    } else {
        if (medium->content)
            camel_object_unref (CAMEL_OBJECT (medium->content));
        medium->content = NULL;
    }
}