istream-attachment-connector.c revision 204ee6ed414f5e4eeb6f6c10763b55daf56f11ac
/* Copyright (c) 2003-2017 Dovecot authors, see the included COPYING file */
#include "lib.h"
#include "array.h"
#include "istream.h"
#include "istream-concat.h"
#include "istream-sized.h"
#include "istream-base64.h"
#include "istream-attachment-connector.h"
struct istream_attachment_connector {
pool_t pool;
struct istream *base_input;
uoff_t base_input_offset, msg_size;
uoff_t encoded_offset;
ARRAY(struct istream *) streams;
};
struct istream_attachment_connector *
istream_attachment_connector_begin(struct istream *base_input, uoff_t msg_size)
{
struct istream_attachment_connector *conn;
pool_t pool;
pool = pool_alloconly_create("istream-attachment-connector", 1024);
conn = p_new(pool, struct istream_attachment_connector, 1);
conn->pool = pool;
conn->base_input = base_input;
conn->base_input_offset = base_input->v_offset;
conn->msg_size = msg_size;
p_array_init(&conn->streams, pool, 8);
i_stream_ref(conn->base_input);
return conn;
}
int istream_attachment_connector_add(struct istream_attachment_connector *conn,
struct istream *decoded_input,
uoff_t start_offset, uoff_t encoded_size,
unsigned int base64_blocks_per_line,
bool base64_have_crlf,
const char **error_r)
{
struct istream *input, *input2;
uoff_t base_prefix_size;
if (start_offset < conn->encoded_offset) {
*error_r = t_strdup_printf(
"Attachment %s points before the previous attachment "
"(%"PRIuUOFF_T" < %"PRIuUOFF_T")",
i_stream_get_name(decoded_input),
start_offset, conn->encoded_offset);
return -1;
}
base_prefix_size = start_offset - conn->encoded_offset;
if (start_offset + encoded_size > conn->msg_size) {
*error_r = t_strdup_printf(
"Attachment %s points outside message "
"(%"PRIuUOFF_T" + %"PRIuUOFF_T" > %"PRIuUOFF_T")",
i_stream_get_name(decoded_input),
start_offset, encoded_size,
conn->msg_size);
return -1;
}
if (base_prefix_size > 0) {
/* add a part of the base message before the attachment */
input = i_stream_create_min_sized_range(conn->base_input,
conn->base_input_offset, base_prefix_size);
i_stream_set_name(input, t_strdup_printf("%s middle",
i_stream_get_name(conn->base_input)));
array_append(&conn->streams, &input, 1);
conn->base_input_offset += base_prefix_size;
conn->encoded_offset += base_prefix_size;
}
conn->encoded_offset += encoded_size;
if (base64_blocks_per_line == 0) {
input = decoded_input;
i_stream_ref(input);
} else {
input = i_stream_create_base64_encoder(decoded_input,
base64_blocks_per_line*4,
base64_have_crlf);
i_stream_set_name(input, t_strdup_printf("%s[base64:%u b/l%s]",
i_stream_get_name(decoded_input),
base64_blocks_per_line,
base64_have_crlf ? ",crlf" : ""));
}
input2 = i_stream_create_sized(input, encoded_size);
array_append(&conn->streams, &input2, 1);
i_stream_unref(&input);
return 0;
}
static void
istream_attachment_connector_free(struct istream_attachment_connector *conn)
{
struct istream *const *streamp, *stream;
array_foreach(&conn->streams, streamp) {
stream = *streamp;
i_stream_unref(&stream);
}
i_stream_unref(&conn->base_input);
pool_unref(&conn->pool);
}
struct istream *
istream_attachment_connector_finish(struct istream_attachment_connector **_conn)
{
struct istream_attachment_connector *conn = *_conn;
struct istream **inputs, *input;
uoff_t trailer_size;
*_conn = NULL;
if (conn->base_input_offset != conn->msg_size) {
i_assert(conn->base_input_offset < conn->msg_size);
if (conn->msg_size != (uoff_t)-1) {
trailer_size = conn->msg_size - conn->encoded_offset;
input = i_stream_create_sized_range(conn->base_input,
conn->base_input_offset,
trailer_size);
i_stream_set_name(input, t_strdup_printf(
"%s trailer", i_stream_get_name(conn->base_input)));
} else {
input = i_stream_create_range(conn->base_input,
conn->base_input_offset,
(uoff_t)-1);
}
array_append(&conn->streams, &input, 1);
}
array_append_zero(&conn->streams);
inputs = array_idx_modifiable(&conn->streams, 0);
input = i_stream_create_concat(inputs);
istream_attachment_connector_free(conn);
return input;
}
void istream_attachment_connector_abort(struct istream_attachment_connector **_conn)
{
struct istream_attachment_connector *conn = *_conn;
*_conn = NULL;
istream_attachment_connector_free(conn);
}