ossp-pkg/sio/sio.c
1.1
/*
** OSSP sio -- stream I/O
** Copyright (c) 2002 The OSSP Project <http://www.ossp.org/>
** Copyright (c) 2002 Cable & Wireless Deutschland <http://www.cw.com/de/>
** Copyright (c) 2002 Ralf S. Engelschall <rse@engelschall.com>
** Copyright (c) 2002 Michael van Elst <mlelstv@dev.de.cw.net>
**
** This file is part of OSSP sio, a library implementing layered I/O
**
** Permission to use, copy, modify, and distribute this software for
** any purpose with or without fee is hereby granted, provided that
** the above copyright notice and this permission notice appear in all
** copies.
**
** THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
** WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
** MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
** IN NO EVENT SHALL THE AUTHORS AND COPYRIGHT HOLDERS AND THEIR
** CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
** USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
** ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
** OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
** OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
** SUCH DAMAGE.
**
** sio.c: stream I/O library implementation
*/
#include <stddef.h>
#include <stdlib.h>
#include "al.h"
#include "sio.h"
#include "sio_module.h"
#include "list.h"
/****************************************************************************/
/* unique library identifier */
const char sio_id[] = "OSSP sio";
/* support for OSSP ex based exception throwing */
#ifdef WITH_EX
#include "ex.h"
#define SIO_RC(rv) \
( (rv) != SIO_OK && (ex_catching && !ex_shielding) \
? (ex_throw(sio_id, NULL, (rv)), (rv)) : (rv) )
#else
#define SIO_RC(rv) (rv)
#endif /* WITH_EX */
struct sio_halfduplex_st;
typedef struct sio_halfduplex_st sio_halfduplex_t;
struct sio_halfduplex_st {
NODE(sio_halfduplex_t) hd;
sio_stage_t *stage;
sio_rc_t (*func)(sio_t *, al_t *, void *);
};
struct sio_st {
struct {
LIST(sio_halfduplex_t) hd;
al_t *al;
} readers;
struct {
LIST(sio_halfduplex_t) hd;
al_t *al;
} writers;
};
struct sio_stage_st {
sio_halfduplex_t reader;
sio_halfduplex_t writer;
void *userdata;
sio_module_t *module;
sio_mode_t rw;
};
/****************************************************************************/
static
sio_rc_t sio_strategy(sio_t *sio, sio_halfduplex_t *chain, al_t *al)
{
sio_rc_t rc;
sio_halfduplex_t *h;
h = chain;
while (h != NULL) {
rc = h->func(sio, al, h->stage->userdata);
if (rc == SIO_UPSTREAM)
h = NEXT(h,hd);
else if (rc == SIO_DOWNSTREAM)
h = NEXT(h,hd);
else
break;
}
return SIO_OK;
}
/**************************************************************************/
sio_rc_t sio_create(sio_t **siop)
{
sio_t *sio;
/* argument sanity check(s) */
if (siop == NULL)
return SIO_RC(SIO_ERR_ARG);
sio = (sio_t *)malloc(sizeof(sio_t));
if (sio == NULL)
return SIO_RC(SIO_ERR_MEM);
LISTINIT(&sio->readers,hd);
LISTINIT(&sio->writers,hd);
*siop = sio;
return SIO_OK;
}
sio_rc_t sio_destroy(sio_t *sio)
{
/* argument sanity check(s) */
if (sio == NULL)
return SIO_RC(SIO_ERR_ARG);
free(sio);
return SIO_OK;
}
sio_rc_t sio_create_stage(sio_t *sio, sio_module_t *siom, sio_stage_t **siosp)
{
sio_rc_t rc;
sio_stage_t *sios;
void *u;
/* argument sanity check(s) */
if (sio == NULL || siom == NULL || siosp == NULL)
return SIO_RC(SIO_ERR_ARG);
sios = (sio_stage_t *)malloc(sizeof(sio_stage_t));
if (sios == NULL)
return SIO_RC(SIO_ERR_MEM);
NODEINIT(&sios->reader,hd);
NODEINIT(&sios->writer,hd);
sios->module = siom;
sios->userdata = u;
sios->rw = SIO_MODE_INVALID;
sios->reader.func = siom->input;
sios->reader.stage = sios;
sios->writer.func = siom->output;
sios->writer.stage = sios;
rc = sios->module->init(sio, sios->userdata);
return SIO_RC(rc);
}
sio_rc_t sio_cofigure_stage(sio_t *sio, sio_stage_t *sios, void *obj, void *value)
{
sio_rc_t rc;
/* argument sanity check(s) */
if (sio == NULL || sios == NULL)
return SIO_RC(SIO_ERR_ARG);
rc = sios->module->configure(sio, sios->userdata, obj, value);
return SIO_RC(rc);
}
sio_rc_t sio_destroy_stage(sio_t *sio, sio_stage_t *sios)
{
sio_rc_t rc;
/* argument sanity check(s) */
if (sio == NULL || sios == NULL)
return SIO_RC(SIO_ERR_ARG);
rc = sios->module->cleanup(sio, sios->userdata);
free(sios);
return SIO_OK;
}
sio_rc_t sio_attach(sio_t *sio, sio_stage_t *sios, sio_mode_t rw)
{
sio_rc_t rc;
/* argument sanity check(s) */
if (sio == NULL || sios == NULL)
return SIO_RC(SIO_ERR_ARG);
/* is module already attached ? */
if (sios->rw != SIO_MODE_INVALID)
return SIO_RC(SIO_ERR_ARG);
/* prepare module for being attached */
rc = sios->module->open(sio, sios->userdata);
if (rc != SIO_OK) return SIO_RC(rc);
switch (rw) {
case SIO_MODE_READ:
ADDTAIL(&sio->readers,hd,&sios->reader);
break;
case SIO_MODE_WRITE:
ADDTAIL(&sio->writers,hd,&sios->writer);
break;
case SIO_MODE_READWRITE:
ADDTAIL(&sio->readers,hd,&sios->reader);
ADDTAIL(&sio->writers,hd,&sios->writer);
break;
default:
return SIO_RC(SIO_ERR_ARG);
}
/* Remember the lists that sios has been attached to */
sios->rw = rw;
return SIO_OK;
}
sio_rc_t sio_detach(sio_t *sio, sio_stage_t *sios)
{
sio_rc_t rc;
/* argument sanity check(s) */
if (sio == NULL || sios == NULL)
return SIO_RC(SIO_ERR_ARG);
switch (sios->rw) {
case SIO_MODE_READ:
REMOVE(&sio->readers,hd,&sios->reader);
break;
case SIO_MODE_WRITE:
REMOVE(&sio->writers,hd,&sios->writer);
break;
case SIO_MODE_READWRITE:
REMOVE(&sio->readers,hd,&sios->reader);
REMOVE(&sio->writers,hd,&sios->writer);
break;
default:
return SIO_RC(SIO_ERR_ARG);
break;
}
rc = sios->module->close(sio, sios->userdata);
return SIO_RC(rc);
}
sio_rc_t sio_input(sio_t *sio, al_t *al, size_t limit)
{
sio_rc_t rc;
al_t *src = sio->readers.al;
size_t n;
/* argument sanity check(s) */
if (sio == NULL || al == NULL)
return SIO_RC(SIO_ERR_ARG);
n = al_bytes(src);
if (n == 0) {
rc = sio_strategy(sio, HEAD(&sio->readers,hd), src);
if (rc != SIO_OK) return SIO_RC(rc);
n = al_bytes(src);
if (n == 0)
return SIO_RC(SIO_ERR_EOF);
}
if (n > limit)
n = limit;
(void) al_splice(src, 0, n, NULL, al); /* XXX - error handling ? */
return SIO_OK;
}
sio_rc_t sio_discard(sio_t *sio)
{
sio_rc_t rc;
al_t *src = sio->readers.al;
size_t n;
/* argument sanity check(s) */
if (sio == NULL)
return SIO_RC(SIO_ERR_ARG);
while ((n = al_bytes(src)) > 0) {
rc = sio_strategy(sio, HEAD(&sio->readers,hd), src);
if (rc != SIO_OK)
break;
}
if (rc == SIO_ERR_EOF)
return SIO_OK;
return SIO_RC(rc);
}
sio_rc_t sio_output(sio_t *sio, al_t *al)
{
sio_rc_t rc;
al_t *dst = sio->writers.al;
size_t n;
/* argument sanity check(s) */
if (sio == NULL || al == NULL)
return SIO_RC(SIO_ERR_ARG);
n = al_bytes(dst);
al_splice(dst, n, 0, al, NULL);
rc = sio_strategy(sio, HEAD(&sio->writers,hd), dst);
return SIO_RC(rc);
}
sio_rc_t sio_flush(sio_t *sio)
{
sio_rc_t rc;
al_t *dst = sio->writers.al;
size_t n;
/* argument sanity check(s) */
if (sio == NULL)
return SIO_RC(SIO_ERR_ARG);
while ((n = al_bytes(dst)) > 0) {
rc = sio_strategy(sio, HEAD(&sio->writers,hd), sio->writers.al);
if (rc != SIO_OK)
break;
}
return SIO_RC(rc);
}
sio_rc_t sio_read(sio_t *sio, char *dst, size_t n, size_t *actualp)
{
al_rc_t arc;
sio_rc_t rc;
al_t *al;
arc = al_create(&al);
if (arc != AL_OK) return SIO_RC(SIO_ERR_INT);
rc = sio_input(sio, al, n);
if (rc == AL_OK) {
arc = al_flatten(al, 0, n, dst, actualp);
if (arc != AL_OK)
rc = SIO_ERR_INT;
}
arc = al_destroy(al);
if (arc != AL_OK) return SIO_RC(SIO_ERR_INT);
return SIO_RC(rc);
}
sio_rc_t sio_write(sio_t *sio, char *src, size_t n, size_t *actualp)
{
al_rc_t arc;
sio_rc_t rc;
al_t *al;
arc = al_create(&al);
if (arc != AL_OK) return SIO_RC(SIO_ERR_INT);
arc = al_append_bytes(al, src, n);
if (arc != AL_OK)
rc = SIO_ERR_INT;
else
rc = sio_output(sio, al);
arc = al_destroy(al);
if (arc != AL_OK) return SIO_RC(SIO_ERR_INT);
return SIO_RC(rc);
}
const char *sio_error(sio_rc_t rc)
{
const char *mess;
switch (rc) {
case SIO_OK: mess = "Everything Ok"; break;
case SIO_ERR_ARG: mess = "Invalid Argument"; break;
case SIO_ERR_MEM: mess = "Not Enough Memory"; break;
case SIO_ERR_EOF: mess = "End Of Data"; break;
case SIO_ERR_SYS: mess = "Operating System Error"; break;
case SIO_ERR_INT: mess = "Internal Error"; break;
case SIO_UPSTREAM: mess = "Invoke Upstream Stage"; break;
case SIO_DOWNSTREAM: mess = "Invoke Downstream Stage"; break;
default: mess = "Invalid Result Code"; break;
}
return mess;
}
