path: root/camel/providers/imap4/camel-imap4-stream.c

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/*  Camel
 *  Copyright (C) 1999-2004 Jeffrey Stedfast
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  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 Street #330, Boston, MA 02111-1307, USA.
 */


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

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

#include "camel-imap4-specials.h"

#include "camel-imap4-stream.h"

#define d(x) x

#define IMAP4_TOKEN_LEN  128

static void camel_imap4_stream_class_init (CamelIMAP4StreamClass *klass);
static void camel_imap4_stream_init (CamelIMAP4Stream *stream, CamelIMAP4StreamClass *klass);
static void camel_imap4_stream_finalize (CamelObject *object);

static ssize_t stream_read (CamelStream *stream, char *buffer, size_t n);
static ssize_t stream_write (CamelStream *stream, const char *buffer, size_t n);
static int stream_flush  (CamelStream *stream);
static int stream_close  (CamelStream *stream);
static gboolean stream_eos (CamelStream *stream);


static CamelStreamClass *parent_class = NULL;


CamelType
camel_imap4_stream_get_type (void)
{
    static CamelType type = 0;
    
    if (!type) {
        type = camel_type_register (CAMEL_STREAM_TYPE,
                        "CamelIMAP4Stream",
                        sizeof (CamelIMAP4Stream),
                        sizeof (CamelIMAP4StreamClass),
                        (CamelObjectClassInitFunc) camel_imap4_stream_class_init,
                        NULL,
                        (CamelObjectInitFunc) camel_imap4_stream_init,
                        (CamelObjectFinalizeFunc) camel_imap4_stream_finalize);
    }
    
    return type;
}

static void
camel_imap4_stream_class_init (CamelIMAP4StreamClass *klass)
{
    CamelStreamClass *stream_class = (CamelStreamClass *) klass;
    
    parent_class = (CamelStreamClass *) camel_type_get_global_classfuncs (CAMEL_STREAM_TYPE);
    
    /* virtual method overload */
    stream_class->read = stream_read;
    stream_class->write = stream_write;
    stream_class->flush = stream_flush;
    stream_class->close = stream_close;
    stream_class->eos = stream_eos;
}

static void
camel_imap4_stream_init (CamelIMAP4Stream *imap4, CamelIMAP4StreamClass *klass)
{
    imap4->stream = NULL;
    
    imap4->mode = CAMEL_IMAP4_STREAM_MODE_TOKEN;
    imap4->disconnected = FALSE;
    imap4->have_unget = FALSE;
    imap4->eol = FALSE;
    
    imap4->literal = 0;
    
    imap4->inbuf = imap4->realbuf + IMAP4_READ_PRELEN;
    imap4->inptr = imap4->inbuf;
    imap4->inend = imap4->inbuf;
    
    imap4->tokenbuf = g_malloc (IMAP4_TOKEN_LEN);
    imap4->tokenptr = imap4->tokenbuf;
    imap4->tokenleft = IMAP4_TOKEN_LEN;
}

static void
camel_imap4_stream_finalize (CamelObject *object)
{
    CamelIMAP4Stream *imap4 = (CamelIMAP4Stream *) object;
    
    if (imap4->stream)
        camel_object_unref (imap4->stream);
    
    g_free (imap4->tokenbuf);
}


static ssize_t
imap4_fill (CamelIMAP4Stream *imap4)
{
    unsigned char *inbuf, *inptr, *inend;
    ssize_t nread;
    size_t inlen;
    
    if (imap4->disconnected) {
        errno = EINVAL;
        return -1;
    }
    
    inbuf = imap4->inbuf;
    inptr = imap4->inptr;
    inend = imap4->inend;
    inlen = inend - inptr;
    
    g_assert (inptr <= inend);
    
    /* attempt to align 'inend' with realbuf + SCAN_HEAD */
    if (inptr >= inbuf) {
        inbuf -= inlen < IMAP4_READ_PRELEN ? inlen : IMAP4_READ_PRELEN;
        memmove (inbuf, inptr, inlen);
        inptr = inbuf;
        inbuf += inlen;
    } else if (inptr > imap4->realbuf) {
        size_t shift;
        
        shift = MIN (inptr - imap4->realbuf, inend - inbuf);
        memmove (inptr - shift, inptr, inlen);
        inptr -= shift;
        inbuf = inptr + inlen;
    } else {
        /* we can't shift... */
        inbuf = inend;
    }
    
    imap4->inptr = inptr;
    imap4->inend = inbuf;
    inend = imap4->realbuf + IMAP4_READ_PRELEN + IMAP4_READ_BUFLEN - 1;
    
    if ((nread = camel_stream_read (imap4->stream, inbuf, inend - inbuf)) == -1)
        return -1;
    else if (nread == 0)
        imap4->disconnected = TRUE;
    
    imap4->inend += nread;
    
    return imap4->inend - imap4->inptr;
}

static ssize_t
stream_read (CamelStream *stream, char *buffer, size_t n)
{
    CamelIMAP4Stream *imap4 = (CamelIMAP4Stream *) stream;
    ssize_t len, nread = 0;
    
    if (imap4->mode == CAMEL_IMAP4_STREAM_MODE_LITERAL) {
        /* don't let our caller read past the end of the literal */
        n = MIN (n, imap4->literal);
    }
    
    if (imap4->inptr < imap4->inend) {
        len = MIN (n, imap4->inend - imap4->inptr);
        memcpy (buffer, imap4->inptr, len);
        imap4->inptr += len;
        nread = len;
    }
    
    if (nread < n) {
        if ((len = camel_stream_read (imap4->stream, buffer + nread, n - nread)) == 0)
            imap4->disconnected = TRUE;
        else if (len == -1)
            return -1;
        
        nread += len;
    }
    
    if (imap4->mode == CAMEL_IMAP4_STREAM_MODE_LITERAL) {
        imap4->literal -= nread;
        
        if (imap4->literal == 0) {
            imap4->mode = CAMEL_IMAP4_STREAM_MODE_TOKEN;
            imap4->eol = TRUE;
        }
    }
    
    return nread;
}

static ssize_t
stream_write (CamelStream *stream, const char *buffer, size_t n)
{
    CamelIMAP4Stream *imap4 = (CamelIMAP4Stream *) stream;
    ssize_t nwritten;
    
    if (imap4->disconnected) {
        errno = EINVAL;
        return -1;
    }
    
    if ((nwritten = camel_stream_write (imap4->stream, buffer, n)) == 0)
        imap4->disconnected = TRUE;
    
    return nwritten;
}

static int
stream_flush (CamelStream *stream)
{
    CamelIMAP4Stream *imap4 = (CamelIMAP4Stream *) stream;
    
    return camel_stream_flush (imap4->stream);
}

static int
stream_close (CamelStream *stream)
{
    CamelIMAP4Stream *imap4 = (CamelIMAP4Stream *) stream;
    
    if (camel_stream_close (imap4->stream) == -1)
        return -1;
    
    camel_object_unref (imap4->stream);
    imap4->stream = NULL;
    
    imap4->disconnected = TRUE;
    
    return 0;
}

static gboolean
stream_eos (CamelStream *stream)
{
    CamelIMAP4Stream *imap4 = (CamelIMAP4Stream *) stream;
    
    if (imap4->eol)
        return TRUE;
    
    if (imap4->disconnected && imap4->inptr == imap4->inend)
        return TRUE;
    
    if (camel_stream_eos (imap4->stream))
        return TRUE;
    
    return FALSE;
}


/**
 * camel_imap4_stream_new:
 * @stream: tcp stream
 *
 * Returns a new imap4 stream
 **/
CamelStream *
camel_imap4_stream_new (CamelStream *stream)
{
    CamelIMAP4Stream *imap4;
    
    g_return_val_if_fail (CAMEL_IS_STREAM (stream), NULL);
    
    imap4 = (CamelIMAP4Stream *) camel_object_new (CAMEL_TYPE_IMAP4_STREAM);
    camel_object_ref (stream);
    imap4->stream = stream;
    
    return (CamelStream *) imap4;
}



#define token_save(imap4, start, len) G_STMT_START {                         \
    if (imap4->tokenleft <= len) {                                       \
        unsigned int tlen, toff;                                    \
                                                                    \
        tlen = toff = imap4->tokenptr - imap4->tokenbuf;              \
        tlen = tlen ? tlen : 1;                                     \
                                                                    \
        while (tlen < toff + len)                                   \
            tlen <<= 1;                                         \
                                                                    \
        imap4->tokenbuf = g_realloc (imap4->tokenbuf, tlen + 1);      \
        imap4->tokenptr = imap4->tokenbuf + toff;                     \
        imap4->tokenleft = tlen - toff;                              \
    }                                                                   \
                                                                        \
    memcpy (imap4->tokenptr, start, len);                                \
    imap4->tokenptr += len;                                              \
    imap4->tokenleft -= len;                                             \
} G_STMT_END

#define token_clear(imap4) G_STMT_START {                                    \
    imap4->tokenleft += imap4->tokenptr - imap4->tokenbuf;                 \
    imap4->tokenptr = imap4->tokenbuf;                                    \
    imap4->literal = 0;                                                  \
} G_STMT_END


/**
 * camel_imap4_stream_next_token:
 * @stream: imap4 stream
 * @token: imap4 token
 *
 * Reads the next token from the imap4 stream and saves it in @token.
 *
 * Returns 0 on success or -1 on fail.
 **/
int
camel_imap4_stream_next_token (CamelIMAP4Stream *stream, camel_imap4_token_t *token)
{
    register unsigned char *inptr;
    unsigned char *inend, *start, *p;
    gboolean escaped = FALSE;
    size_t literal = 0;
    guint32 nz_number;
    int ret;
    
    g_return_val_if_fail (CAMEL_IS_IMAP4_STREAM (stream), -1);
    g_return_val_if_fail (stream->mode != CAMEL_IMAP4_STREAM_MODE_LITERAL, -1);
    g_return_val_if_fail (token != NULL, -1);
    
    if (stream->have_unget) {
        memcpy (token, &stream->unget, sizeof (camel_imap4_token_t));
        stream->have_unget = FALSE;
        return 0;
    }
    
    token_clear (stream);
    
    inptr = stream->inptr;
    inend = stream->inend;
    *inend = '\0';
    
    do {
        if (inptr == inend) {
            if ((ret = imap4_fill (stream)) < 0) {
                token->token = CAMEL_IMAP4_TOKEN_ERROR;
                return -1;
            } else if (ret == 0) {
                token->token = CAMEL_IMAP4_TOKEN_NO_DATA;
                return 0;
            }
            
            inptr = stream->inptr;
            inend = stream->inend;
            *inend = '\0';
        }
        
        while (*inptr == ' ' || *inptr == '\r')
            inptr++;
    } while (inptr == inend);
    
    do {
        if (inptr < inend) {
            if (*inptr == '"') {
                /* qstring token */
                escaped = FALSE;
                start = inptr;
                
                /* eat the beginning " */
                inptr++;
                
                p = inptr;
                while (inptr < inend) {
                    if (*inptr == '"' && !escaped)
                        break;
                    
                    if (*inptr == '\\' && !escaped) {
                        token_save (stream, p, inptr - p);
                        escaped = TRUE;
                        inptr++;
                        p = inptr;
                    } else {
                        inptr++;
                        escaped = FALSE;
                    }
                }
                
                token_save (stream, p, inptr - p);
                
                if (inptr == inend) {
                    stream->inptr = start;
                    goto refill;
                }
                
                /* eat the ending " */
                inptr++;
                
                /* nul-terminate the atom token */
                token_save (stream, "", 1);
                
                token->token = CAMEL_IMAP4_TOKEN_QSTRING;
                token->v.qstring = stream->tokenbuf;
                
                d(fprintf (stderr, "token: \"%s\"\n", token->v.qstring));
                
                break;
            } else if (strchr ("+*()[]\n", *inptr)) {
                /* special character token */
                token->token = *inptr++;
#if d(!)0
                if (token->token != '\n')
                    fprintf (stderr, "token: %c\n", token->token);
                else
                    fprintf (stderr, "token: \\n\n");
#endif
                break;
            } else if (*inptr == '{') {
                /* literal identifier token */
                if ((p = strchr (inptr, '}')) && strchr (p, '\n')) {
                    inptr++;
                    
                    while (isdigit ((int) *inptr) && literal < UINT_MAX / 10)
                        literal = (literal * 10) + (*inptr++ - '0');
                    
                    if (*inptr != '}') {
                        if (isdigit ((int) *inptr))
                            g_warning ("illegal literal identifier: literal too large");
                        else if (*inptr != '+')
                            g_warning ("illegal literal identifier: garbage following size");
                        
                        while (*inptr != '}')
                            inptr++;
                    }
                    
                    /* skip over '}' */
                    inptr++;
                    
                    /* skip over any trailing whitespace */
                    while (*inptr == ' ' || *inptr == '\r')
                        inptr++;
                    
                    if (*inptr != '\n') {
                        g_warning ("illegal token following literal identifier: %s", inptr);
                        
                        /* skip ahead to the eoln */
                        inptr = strchr (inptr, '\n');
                    }
                    
                    /* skip over '\n' */
                    inptr++;
                    
                    token->token = CAMEL_IMAP4_TOKEN_LITERAL;
                    token->v.literal = literal;
                    
                    d(fprintf (stderr, "token: {%u}\n", literal));
                    
                    stream->mode = CAMEL_IMAP4_STREAM_MODE_LITERAL;
                    stream->literal = literal;
                    stream->eol = FALSE;
                    
                    break;
                } else {
                    stream->inptr = inptr;
                    goto refill;
                }
            } else if (*inptr >= '0' && *inptr <= '9') {
                /* number token */
                *inend = '\0';
                nz_number = strtoul ((char *) inptr, (char **) &start, 10);
                if (start == inend)
                    goto refill;
                
                if (*start == ':' || *start == ',') {
                    /* workaround for 'set' tokens (APPENDUID / COPYUID) */
                    goto atom_token;
                }
                
                inptr = start;
                token->token = CAMEL_IMAP4_TOKEN_NUMBER;
                token->v.number = nz_number;
                
                d(fprintf (stderr, "token: %u\n", nz_number));
                
                break;
            } else if (is_atom (*inptr)) {
            atom_token:
                /* simple atom token */
                start = inptr;
                
                while (inptr < inend && is_atom (*inptr))
                    inptr++;
                
                if (inptr == inend) {
                    stream->inptr = start;
                    goto refill;
                }
                
                token_save (stream, start, inptr - start);
                
                /* nul-terminate the atom token */
                token_save (stream, "", 1);
                
                if (!strcmp (stream->tokenbuf, "NIL")) {
                    /* special atom token */
                    token->token = CAMEL_IMAP4_TOKEN_NIL;
                    d(fprintf (stderr, "token: NIL\n"));
                } else {
                    token->token = CAMEL_IMAP4_TOKEN_ATOM;
                    token->v.atom = stream->tokenbuf;
                    d(fprintf (stderr, "token: %s\n", token->v.atom));
                }
                
                break;
            } else if (*inptr == '\\') {
                /* possible flag token ("\" atom) */
                start = inptr++;
                
                while (inptr < inend && is_atom (*inptr))
                    inptr++;
                
                if (inptr == inend) {
                    stream->inptr = start;
                    goto refill;
                }
                
                /* handle the \* case */
                if ((inptr - start) == 1 && *inptr == '*')
                    inptr++;
                
                if ((inptr - start) > 1) {
                    token_save (stream, start, inptr - start);
                    
                    /* nul-terminate the flag token */
                    token_save (stream, "", 1);
                    
                    token->token = CAMEL_IMAP4_TOKEN_FLAG;
                    token->v.atom = stream->tokenbuf;
                    d(fprintf (stderr, "token: %s\n", token->v.atom));
                } else {
                    token->token = '\\';
                    d(fprintf (stderr, "token: %c\n", token->token));
                }
                break;
            } else if (is_lwsp (*inptr)) {
                inptr++;
            } else {
                /* unknown character token? */
                token->token = *inptr++;
                d(fprintf (stderr, "token: %c\n", token->token));
                break;
            }
        } else {
        refill:
            token_clear (stream);
            
            if (imap4_fill (stream) <= 0) {
                token->token = CAMEL_IMAP4_TOKEN_ERROR;
                return -1;
            }
            
            inptr = stream->inptr;
            inend = stream->inend;
            *inend = '\0';
        }
    } while (inptr < inend);
    
    stream->inptr = inptr;
    
    return 0;
}


/**
 * camel_imap4_stream_unget_token:
 * @stream: imap4 stream
 * @token: token to 'unget'
 *
 * Ungets an imap4 token (as in ungetc()).
 *
 * Note: you may *ONLY* unget a single token. Trying to unget another
 * token will fail.
 *
 * Returns 0 on success or -1 on fail.
 **/
int
camel_imap4_stream_unget_token (CamelIMAP4Stream *stream, camel_imap4_token_t *token)
{
    if (stream->have_unget)
        return -1;
    
    if (token->token != CAMEL_IMAP4_TOKEN_NO_DATA) {
        memcpy (&stream->unget, token, sizeof (camel_imap4_token_t));
        stream->have_unget = TRUE;
    }
    
    return 0;
}


/**
 * camel_imap4_stream_line:
 * @stream: imap4 stream
 * @line: line pointer
 * @len: line length
 *
 * Reads a single line from the imap4 stream and points @line at an
 * internal buffer containing the line read and sets @len to the
 * length of the line buffer.
 *
 * Returns -1 on error, 0 if the line read is complete, or 1 if the
 * read is incomplete.
 **/
int
camel_imap4_stream_line (CamelIMAP4Stream *stream, unsigned char **line, size_t *len)
{
    register unsigned char *inptr;
    unsigned char *inend;
    
    g_return_val_if_fail (CAMEL_IS_IMAP4_STREAM (stream), -1);
    g_return_val_if_fail (stream->mode != CAMEL_IMAP4_STREAM_MODE_LITERAL, -1);
    g_return_val_if_fail (line != NULL, -1);
    g_return_val_if_fail (len != NULL, -1);
    
    inptr = stream->inptr;
    inend = stream->inend;
    
    if (inptr == inend || ((inend - inptr) < 2 && *inptr != '\n')) {
        if (imap4_fill (stream) == -1 && stream->inptr == stream->inend)
            return -1;
    }
    
    *line = stream->inptr;
    inptr = stream->inptr;
    inend = stream->inend;
    *inend = '\n';
    
    while (*inptr != '\n')
        inptr++;
    
    *len = (inptr - stream->inptr);
    
    if (inptr > stream->inptr && inptr[-1] == '\r')
        inptr[-1] = '\0';
    
    if (inptr < inend) {
        /* got the eoln */
        inptr[0] = '\0';
        *len += 1;
        
        stream->inptr = inptr + 1;
        
        return 0;
    }
    
    stream->inptr = inptr;
    
    return 1;
}


/**
 * camel_imap4_stream_literal:
 * @stream: IMAP stream
 * @literal: literal pointer
 * @len: literal length
 *
 * Sets @literal to the beginning of the next chunk of the literal
 * buffer from the IMAP stream and sets @len to the length of the
 * @literal buffer.
 *
 * Returns >0 if more literal data exists, 0 if the end of the literal
 * has been reached or -1 on fail.
 **/
int
camel_imap4_stream_literal (CamelIMAP4Stream *stream, unsigned char **literal, size_t *len)
{
    unsigned char *inptr, *inend;
    size_t nread;
    
    g_return_val_if_fail (CAMEL_IS_IMAP4_STREAM (stream), -1);
    g_return_val_if_fail (stream->mode == CAMEL_IMAP4_STREAM_MODE_LITERAL, -1);
    g_return_val_if_fail (literal != NULL, -1);
    g_return_val_if_fail (len != NULL, -1);
    
    if (stream->eol) {
        *len = 0;
        return 0;
    }
    
    if ((stream->inend - stream->inptr) < 1) {
        /* keep our buffer full to the optimal size */
        if (imap4_fill (stream) == -1 && stream->inptr == stream->inend)
            return -1;
    }
    
    *literal = inptr = stream->inptr;
    inend = stream->inend;
    if ((inend - inptr) > stream->literal)
        inend = inptr + stream->literal;
    else
        inend = stream->inend;
    
    *len = nread = inend - inptr;
    
    stream->literal -= nread;
    stream->inptr += nread;
    
    if (stream->literal == 0) {
        stream->mode = CAMEL_IMAP4_STREAM_MODE_TOKEN;
        stream->eol = TRUE;
        return 0;
    }
    
    return 1;
}