libosmocore/src/usb/osmo_libusb.c

138 lines
3.9 KiB
C

/* libosmocore integration with libusb-1.0
*
* (C) 2019 by Harald Welte <laforge@gnumonks.org>
* All Rights Reserved.
*
* SPDX-License-Identifier: GPL-2.0+
*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#include <errno.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <poll.h>
#include <osmocom/core/utils.h>
#include <osmocom/core/logging.h>
#include <osmocom/core/select.h>
#include <osmocom/core/talloc.h>
#include <libusb.h>
/***********************************************************************
* logging integration
***********************************************************************/
#define DLUSB DLINP
#ifdef LIBUSB_LOG_CB_CONTEXT /* introduced in 1.0.23 */
static const int usb2logl[] = {
[LIBUSB_LOG_LEVEL_NONE] = LOGL_FATAL,
[LIBUSB_LOG_LEVEL_ERROR] = LOGL_ERROR,
[LIBUSB_LOG_LEVEL_WARNING] = LOGL_NOTICE,
[LIBUSB_LOG_LEVEL_INFO] = LOGL_INFO,
[LIBUSB_LOG_LEVEL_DEBUG] = LOGL_DEBUG,
};
/* called by libusb if it wants to log something */
static void libosmo_usb_log_cb(libusb_context *luctx, enum libusb_log_level level_usb, const char *str)
{
int level = LOGL_NOTICE;
if (level_usb < ARRAY_SIZE(usb2logl))
level = usb2logl[level_usb];
LOGP(DLUSB, level, "%s", str);
}
#endif /* LIBUSB_LOG_CB_CONTEXT */
/***********************************************************************
* select loop integration
***********************************************************************/
static int osmo_usb_fd_cb(struct osmo_fd *ofd, unsigned int what)
{
libusb_context *luctx = ofd->data;
/* we assume that we're running Linux v2.6.27 with timerfd support here
* and hence don't have to perform manual timeout handling. See
* "Notes on time-based events" at
* http://libusb.sourceforge.net/api-1.0/group__libusb__poll.html */
struct timeval zero_tv = { 0, 0 };
libusb_handle_events_timeout(luctx, &zero_tv);
return 0;
}
/* called by libusb if it wants to add a file-descriptor */
static void osmo_usb_added_cb(int fd, short events, void *user_data)
{
struct osmo_fd *ofd = talloc_zero(OTC_GLOBAL, struct osmo_fd);
libusb_context *luctx = user_data;
unsigned int when = 0;
if (events & POLLIN)
when |= OSMO_FD_READ;
if (events & POLLOUT)
when |= OSMO_FD_WRITE;
osmo_fd_setup(ofd, fd, when, osmo_usb_fd_cb, luctx, 0);
osmo_fd_register(ofd);
}
/* called by libusb if it wants to remove a file-descriptor */
static void osmo_usb_removed_cb(int fd, void *user_data)
{
struct osmo_fd *ofd = osmo_fd_get_by_fd(fd);
if (!fd)
return;
osmo_fd_unregister(ofd);
talloc_free(ofd);
}
/***********************************************************************
* initialization
***********************************************************************/
int osmo_libusb_init(libusb_context **pluctx)
{
libusb_context *luctx = NULL;
int rc;
rc = libusb_init(pluctx);
if (rc != 0)
return rc;
if (pluctx)
luctx = *pluctx;
#ifdef LIBUSB_LOG_CB_CONTEXT /* introduced in 1.0.23 */
libusb_set_log_cb(luctx, &libosmo_usb_log_cb, LIBUSB_LOG_CB_CONTEXT);
#endif
libusb_set_pollfd_notifiers(luctx, osmo_usb_added_cb, osmo_usb_removed_cb, luctx);
return 0;
}
void osmo_libusb_exit(libusb_context *luctx)
{
/* we just assume libusb is cleaning up all the osmo_Fd's we've allocated */
libusb_exit(luctx);
}