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/*
Copyright (C) 2004, 2005 Stephen Bach
This file is part of the Viewglob package.
Viewglob 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.
Viewglob 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 Viewglob; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "common.h"
#include "connection.h"
#include "actions.h"
#include "hardened-io.h"
#include <string.h>
/* Initialize the given Connection. */
void connection_init(Connection* cnct, gchar* name, int fd_in, int fd_out,
gchar* buf, gsize buflen, enum process_level pl) {
g_return_if_fail(cnct != NULL);
g_return_if_fail(name != NULL);
g_return_if_fail(fd_in >= 0);
g_return_if_fail(fd_out >= 0);
g_return_if_fail(buf != NULL);
cnct->name = name;
cnct->fd_in = fd_in;
cnct->fd_out = fd_out;
cnct->buf = buf;
cnct->size = buflen;
cnct->filled = 0;
cnct->pos = 0;
cnct->seglen = 0;
cnct->pl = pl;
cnct->status = MS_NO_MATCH;
cnct->holdover = NULL;
cnct->ho_written = FALSE;
cnct->skip = 0;
/* The shell_status is of course only relevant to the user shell. */
cnct->ss = SS_EXECUTING;
}
/* Free the read/write and holdover buffers. */
void connection_free(Connection* cnct) {
g_return_if_fail(cnct != NULL);
if (cnct->holdover) {
g_free(cnct->holdover);
cnct->holdover = NULL;
}
}
/* Prepend the holdover from the last read onto the beginning
of the current buffer. If there is no holdover, just initialize the
offsets. */
void prepend_holdover(Connection* b) {
g_return_if_fail(b != NULL);
if (b->holdover) {
size_t ho_len;
ho_len = strlen(b->holdover);
/* Copy over the holdover and then free it. */
memcpy(b->buf, b->holdover, ho_len);
g_free(b->holdover);
b->holdover = NULL;
b->filled = ho_len;
b->pos = 0;
/* b->seglen has not changed since the create_holdover(). */
if (b->ho_written)
b->skip = ho_len;
else
b->skip = 0;
}
else {
b->filled = 0;
b->pos = 0;
b->seglen = 0;
b->skip = 0;
}
}
/* Cut the segment under investigation into a holdover, to be prepended to
a later buffer. */
void create_holdover(Connection* b, gboolean write_later) {
g_return_if_fail(b != NULL);
g_return_if_fail(b->holdover == NULL);
/* Copy as null-terminated string. */
b->holdover = g_strndup(b->buf + b->pos, b->seglen);
if (write_later) {
/* Writing of this segment is postponed until after the next buffer
read. */
b->filled -= b->seglen;
b->ho_written = FALSE;
}
else
b->ho_written = TRUE;
}
/* Remove the segment under investigation from the buffer. */
void eat_segment(Connection* b) {
g_return_if_fail(b != NULL);
char* start;
char* end;
size_t length;
start = b->buf + b->pos;
end = b->buf + b->pos + b->seglen + 1;
length = b->filled - (b->pos + b->seglen + 1);
memmove(start, end, length);
b->filled -= b->seglen + 1;
b->seglen = 0;
/* b->pos is in the right spot because of the eat. */
}
/* Skip the current segment. */
void pass_segment(Connection* b) {
g_return_if_fail(b != NULL);
b->pos += b->seglen + 1;
b->seglen = 0;
}
/* Read in from the connection. */
gboolean connection_read(Connection* cnct) {
g_return_val_if_fail(cnct != NULL, FALSE);
g_return_val_if_fail(cnct->filled < cnct->size, FALSE);
gssize nread;
gboolean ok = TRUE;
switch (hardened_read(cnct->fd_in, cnct->buf + cnct->filled,
cnct->size - cnct->filled, &nread)) {
case IOR_OK:
cnct->filled += nread;
break;
case IOR_ERROR:
if (errno == EIO) {
/* We often get an EIO here when the user shell exits. For
now we pretend it's a gentle error. FIXME, though, as
there's gotta be a side effect. */
action_queue(A_EXIT);
}
else {
g_critical("Read problem from %s: %s", cnct->name,
g_strerror(errno));
ok = FALSE;
}
break;
case IOR_EOF:
action_queue(A_EXIT);
break;
default:
g_return_val_if_reached(FALSE);
}
return ok;
}
/* Write out the full (filled) buffer. */
gboolean connection_write(Connection* cnct) {
g_return_val_if_fail(cnct != NULL, FALSE);
gboolean ok = TRUE;
if (cnct->filled) {
switch (write_all(cnct->fd_out, cnct->buf + cnct->skip,
cnct->filled - cnct->skip)) {
case IOR_OK:
break;
case IOR_ERROR:
g_critical("Problem writing for %s: %s", cnct->name,
g_strerror(errno));
ok = FALSE;
break;
default:
g_return_val_if_reached(FALSE);
}
}
return ok;
}
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