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 3 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         struct jaylink_context *context;
  47
  48         if (!ctx)
  49                 return JAYLINK_ERR_ARG;
  50
  51         context = malloc(sizeof(struct jaylink_context));
  52
  53         if (!context)
  54                 return JAYLINK_ERR_MALLOC;
  55
  56         if (libusb_init(&context->usb_ctx) < 0) {
  57                 free(context);
  58                 return JAYLINK_ERR;
  59         }
  60
  61         context->devs = NULL;
  62
  63         /* Show error and warning messages by default. */
  64         context->log_level = JAYLINK_LOG_LEVEL_WARNING;
  65
  66         *ctx = context;
  67
  68         return JAYLINK_OK;
  69 }
  70
  71 /**
  72  * Shutdown libjaylink.
  73  *
  74  * @param[in,out] ctx libjaylink context.
  75  */
  76 JAYLINK_API void jaylink_exit(struct jaylink_context *ctx)
  77 {
  78         if (!ctx)
  79                 return;
  80
  81         list_free(ctx->devs);
  82         libusb_exit(ctx->usb_ctx);
  83         free(ctx);
  84 }