diff options
Diffstat (limited to 'backend/escl/escl_devices.c')
| -rw-r--r-- | backend/escl/escl_devices.c | 185 |
1 files changed, 185 insertions, 0 deletions
diff --git a/backend/escl/escl_devices.c b/backend/escl/escl_devices.c new file mode 100644 index 0000000..7ecbe31 --- /dev/null +++ b/backend/escl/escl_devices.c @@ -0,0 +1,185 @@ +/* sane - Scanner Access Now Easy. + + Copyright (C) 2019 Touboul Nathane + Copyright (C) 2019 Thierry HUCHARD <thierry@ordissimo.com> + + This file is part of the SANE package. + + SANE 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 3 of the License, or (at your + option) any later version. + + SANE 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 sane; see the file COPYING. If not, write to the Free + Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + + This file implements a SANE backend for eSCL scanners. */ + +#define DEBUG_DECLARE_ONLY +#include "../include/sane/config.h" + +#include "escl.h" + +#include <assert.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include <avahi-client/lookup.h> +#include <avahi-common/error.h> +#include <avahi-common/simple-watch.h> + +#include "../include/sane/sanei.h" + +static AvahiSimplePoll *simple_poll = NULL; + +/** + * \fn static void resolve_callback(AvahiServiceResolver *r, AVAHI_GCC_UNUSED + * AvahiIfIndex interface, AVAHI_GCC_UNUSED AvahiProtocol protocol, + * AvahiResolverEvent event, const char *name, + * const char *type, const char *domain, const char *host_name, + * const AvahiAddress *address, uint16_t port, + * AvahiStringList *txt, AvahiLookupResultFlags flags, + * void *userdata) + * \brief Callback function that will check if the selected scanner follows the escl + * protocol or not. + */ +static void +resolve_callback(AvahiServiceResolver *r, AVAHI_GCC_UNUSED AvahiIfIndex interface, + AVAHI_GCC_UNUSED AvahiProtocol protocol, + AvahiResolverEvent event, const char *name, + const char __sane_unused__ *type, + const char __sane_unused__ *domain, + const char __sane_unused__ *host_name, + const AvahiAddress *address, uint16_t port, AvahiStringList *txt, + AvahiLookupResultFlags __sane_unused__ flags, + void __sane_unused__ *userdata) +{ + char a[AVAHI_ADDRESS_STR_MAX], *t; + assert(r); + switch (event) { + case AVAHI_RESOLVER_FAILURE: + break; + case AVAHI_RESOLVER_FOUND: + avahi_address_snprint(a, sizeof(a), address); + t = avahi_string_list_to_string(txt); + if (strstr(t, "\"rs=eSCL\"") || strstr(t, "\"rs=/eSCL\"")) + escl_device_add(port, name, a, (char*)type); + } +} + +/** + * \fn static void browse_callback(AvahiServiceBrowser *b, AvahiIfIndex interface, + * AvahiProtocol protocol, AvahiBrowserEvent event, const char *name, + * const char *type, const char *domain, + * AVAHI_GCC_UNUSED AvahiLookupResultFlags flags, void* userdata) + * \brief Callback function that will browse tanks to 'avahi' the scanners + * connected in network. + */ +static void +browse_callback(AvahiServiceBrowser *b, AvahiIfIndex interface, + AvahiProtocol protocol, AvahiBrowserEvent event, + const char *name, const char *type, + const char *domain, + AVAHI_GCC_UNUSED AvahiLookupResultFlags flags, + void* userdata) +{ + AvahiClient *c = userdata; + assert(b); + switch (event) { + case AVAHI_BROWSER_FAILURE: + avahi_simple_poll_quit(simple_poll); + return; + case AVAHI_BROWSER_NEW: + if (!(avahi_service_resolver_new(c, interface, protocol, name, + type, domain, + AVAHI_PROTO_UNSPEC, 0, + resolve_callback, c))) + break; + case AVAHI_BROWSER_REMOVE: + break; + case AVAHI_BROWSER_ALL_FOR_NOW: + case AVAHI_BROWSER_CACHE_EXHAUSTED: + if (event != AVAHI_BROWSER_CACHE_EXHAUSTED) + avahi_simple_poll_quit(simple_poll); + break; + } +} + +/** + * \fn static void client_callback(AvahiClient *c, AvahiClientState state, + * AVAHI_GCC_UNUSED void *userdata) + * \brief Callback Function that quit if it doesn't find a connected scanner, + * possible thanks the "Hello Protocol". + * --> Waiting for a answer by the scanner to continue the avahi process. + */ +static void +client_callback(AvahiClient *c, AvahiClientState state, + AVAHI_GCC_UNUSED void *userdata) +{ + assert(c); + if (state == AVAHI_CLIENT_FAILURE) + avahi_simple_poll_quit(simple_poll); +} + +/** + * \fn ESCL_Device *escl_devices(SANE_Status *status) + * \brief Function that calls all the avahi functions and then, recovers the + * connected eSCL devices. + * This function is called in the 'sane_get_devices' function. + * + * \return NULL (the eSCL devices found) + */ +ESCL_Device * +escl_devices(SANE_Status *status) +{ + AvahiClient *client = NULL; + AvahiServiceBrowser *sb = NULL; + int error; + + *status = SANE_STATUS_GOOD; + if (!(simple_poll = avahi_simple_poll_new())) { + DBG( 1, "Failed to create simple poll object.\n"); + *status = SANE_STATUS_INVAL; + goto fail; + } + client = avahi_client_new(avahi_simple_poll_get(simple_poll), 0, + client_callback, NULL, &error); + if (!client) { + DBG( 1, "Failed to create client: %s\n", avahi_strerror(error)); + *status = SANE_STATUS_INVAL; + goto fail; + } + if (!(sb = avahi_service_browser_new(client, AVAHI_IF_UNSPEC, + AVAHI_PROTO_UNSPEC, "_uscan._tcp", + NULL, 0, browse_callback, client))) { + DBG( 1, "Failed to create service browser: %s\n", + avahi_strerror(avahi_client_errno(client))); + *status = SANE_STATUS_INVAL; + goto fail; + } + if (!(sb = avahi_service_browser_new(client, AVAHI_IF_UNSPEC, + AVAHI_PROTO_UNSPEC, + "_uscans._tcp", NULL, 0, + browse_callback, client))) { + DBG( 1, "Failed to create service browser: %s\n", + avahi_strerror(avahi_client_errno(client))); + *status = SANE_STATUS_INVAL; + goto fail; + } + avahi_simple_poll_loop(simple_poll); +fail: + if (sb) + avahi_service_browser_free(sb); + if (client) + avahi_client_free(client); + if (simple_poll) + avahi_simple_poll_free(simple_poll); + return (NULL); +} |