libjaylink/core.c

   1 /*
   2  * This file is part of the libjaylink project.
   3  *
   4  * Copyright (C) 2014-2015 Marc Schink <jaylink-dev@marcschink.de>
   5  *
   6  * This program is free software: you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation, either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <stdlib.h>
  21 #include <libusb.h>
  22
  23 #include "libjaylink.h"
  24 #include "libjaylink-internal.h"
  25
  26 /**
  27  * @file
  28  *
  29  * Core library functions.
  30  */
  31
  32 /**
  33  * Initialize libjaylink.
  34  *
  35  * This function must be called before any other libjaylink function is called.
  36  *
  37  * @param[out] ctx Newly allocated libjaylink context on success, and undefined
  38  *                 on failure.
  39  *
  40  * @retval JAYLINK_OK Success.
  41  * @retval JAYLINK_ERR_ARG Invalid arguments.
  42  * @retval JAYLINK_ERR Other error conditions.
  43  */
  44 JAYLINK_API int jaylink_init(struct jaylink_context **ctx)
  45 {
  46         int ret;
  47         struct jaylink_context *context;
  48
  49         if (!ctx)
  50                 return JAYLINK_ERR_ARG;
  51
  52         context = malloc(sizeof(struct jaylink_context));
  53
  54         if (!context)
  55                 return JAYLINK_ERR_MALLOC;
  56
  57         if (libusb_init(&context->usb_ctx) < 0) {
  58                 free(context);
  59                 return JAYLINK_ERR;
  60         }
  61
  62         context->devs = NULL;
  63
  64         /* Show error and warning messages by default. */
  65         context->log_level = JAYLINK_LOG_LEVEL_WARNING;
  66
  67         context->log_callback = &log_vprintf;
  68         context->log_callback_data = NULL;
  69
  70         ret = jaylink_log_set_domain(context, JAYLINK_LOG_DOMAIN_DEFAULT);
  71
  72         if (ret != JAYLINK_OK) {
  73                 free(context);
  74                 return ret;
  75         }
  76
  77         *ctx = context;
  78
  79         return JAYLINK_OK;
  80 }
  81
  82 /**
  83  * Shutdown libjaylink.
  84  *
  85  * @param[in,out] ctx libjaylink context.
  86  */
  87 JAYLINK_API void jaylink_exit(struct jaylink_context *ctx)
  88 {
  89         if (!ctx)
  90                 return;
  91
  92         list_free(ctx->devs);
  93         libusb_exit(ctx->usb_ctx);
  94         free(ctx);
  95 }