1 /* Copyright (C) 2010-2018 The RetroArch team 2 * 3 * --------------------------------------------------------------------------------------- 4 * The following license statement only applies to this file (nbio.h). 5 * --------------------------------------------------------------------------------------- 6 * 7 * Permission is hereby granted, free of charge, 8 * to any person obtaining a copy of this software and associated documentation files (the "Software"), 9 * to deal in the Software without restriction, including without limitation the rights to 10 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, 11 * and to permit persons to whom the Software is furnished to do so, subject to the following conditions: 12 * 13 * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, 16 * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. 18 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, 19 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 20 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 21 */ 22 23 #ifndef __LIBRETRO_SDK_NBIO_H 24 #define __LIBRETRO_SDK_NBIO_H 25 26 #include <stddef.h> 27 #include <boolean.h> 28 29 #include <retro_common_api.h> 30 31 RETRO_BEGIN_DECLS 32 33 #ifndef NBIO_READ 34 #define NBIO_READ 0 35 #endif 36 37 #ifndef NBIO_WRITE 38 #define NBIO_WRITE 1 39 #endif 40 41 #ifndef NBIO_UPDATE 42 #define NBIO_UPDATE 2 43 #endif 44 45 /* these two are blocking; nbio_iterate always returns true, but that operation (or something earlier) may take arbitrarily long */ 46 #ifndef BIO_READ 47 #define BIO_READ 3 48 #endif 49 50 #ifndef BIO_WRITE 51 #define BIO_WRITE 4 52 #endif 53 54 typedef struct nbio_intf 55 { 56 void *(*open)(const char * filename, unsigned mode); 57 58 void (*begin_read)(void *data); 59 60 void (*begin_write)(void *data); 61 62 bool (*iterate)(void *data); 63 64 void (*resize)(void *data, size_t len); 65 66 void *(*get_ptr)(void *data, size_t* len); 67 68 void (*cancel)(void *data); 69 70 void (*free)(void *data); 71 72 /* Human readable string. */ 73 const char *ident; 74 } nbio_intf_t; 75 76 /* 77 * Creates an nbio structure for performing the 78 * given operation on the given file. 79 */ 80 void *nbio_open(const char * filename, unsigned mode); 81 82 /* 83 * Starts reading the given file. When done, it will be available in nbio_get_ptr. 84 * Can not be done if the structure was created with {N,}BIO_WRITE. 85 */ 86 void nbio_begin_read(void *data); 87 88 /* 89 * Starts writing to the given file. Before this, you should've copied the data to nbio_get_ptr. 90 * Can not be done if the structure was created with {N,}BIO_READ. 91 */ 92 void nbio_begin_write(void *data); 93 94 /* 95 * Performs part of the requested operation, or checks how it's going. 96 * When it returns true, it's done. 97 */ 98 bool nbio_iterate(void *data); 99 100 /* 101 * Resizes the file up to the given size; cannot shrink. 102 * Can not be done if the structure was created with {N,}BIO_READ. 103 */ 104 void nbio_resize(void *data, size_t len); 105 106 /* 107 * Returns a pointer to the file data. Writable only if structure was not created with {N,}BIO_READ. 108 * If any operation is in progress, the pointer will be NULL, but len will still be correct. 109 */ 110 void* nbio_get_ptr(void *data, size_t* len); 111 112 /* 113 * Stops any pending operation, allowing the object to be freed. 114 */ 115 void nbio_cancel(void *data); 116 117 /* 118 * Deletes the nbio structure and its associated pointer. 119 */ 120 void nbio_free(void *data); 121 122 RETRO_END_DECLS 123 124 #endif 125