sc/memory-map/sc_mmap.h
2021-02-14 16:19:26 +03:00

119 lines
3.4 KiB
C

/*
* MIT License
*
* Copyright (c) 2021 Ozan Tezcan
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#ifndef SC_MMAP_H
#define SC_MMAP_H
#include <fcntl.h>
#include <stdbool.h>
#include <stdlib.h>
#define SC_MMAP_VERSION "1.0.0"
#if defined(_WIN32)
#include <windows.h>
#include <memoryapi.h>
#define PROT_READ FILE_MAP_READ
#define PROT_WRITE FILE_MAP_WRITE
#define MAP_FIXED 0x01
#define MAP_ANONYMOUS 0x02
#define MAP_SHARED 0x04
#else /*POSIX*/
#include <sys/mman.h>
#endif
struct sc_mmap
{
int fd;
unsigned char* ptr; // memory map start address
size_t len; // memory map length
char err[128];
};
/**
* Initializes mmap structure, opens file and maps into memory. If file is
* smaller than 'offset + len' and PROT_WRITE flag is provided, then the file
* will be expanded to 'offset + len' bytes.
*
* @param m mmap
* @param name file name
* @param file_flags flags for open(), e.g : O_RDWR | O_CREAT
* @param prot prot flags, e.g : PROT_READ | PROT_WRITE
* @param map_flags mmap flags, e.g : MAP_SHARED
* @param offset offset
* @param len len
* @return '0' on success, negative on failure,
* call sc_mmap_err() for error string.
*/
int sc_mmap_init(struct sc_mmap* m, const char* name, int file_flags, int prot,
int map_flags, size_t offset, size_t len);
/**
* @param m mmap
* @return '0' on success, '-1' on error, call sc_mmap_err() for details.
*/
int sc_mmap_term(struct sc_mmap* m);
/**
* @param m mmap
* @param offset offset
* @param len len
* @return '0' on success, negative on failure,
* call sc_mmap_err() for error string.
*/
int sc_mmap_msync(struct sc_mmap* m, size_t offset, size_t len);
/**
* @param m mmap
* @param offset offset
* @param len len
* @return '0' on success, negative on failure,
* call sc_mmap_err() for error string.
*/
int sc_mmap_mlock(struct sc_mmap* m, size_t offset, size_t len);
/**
* @param m mmap
* @param offset offset
* @param len len
* @return '0' on success, negative on failure,
* call sc_mmap_err() for error string.
*/
int sc_mmap_munlock(struct sc_mmap* m, size_t offset, size_t len);
/**
* @param m mmap
* @return last error string.
*/
const char *sc_mmap_err(struct sc_mmap *m);
#endif