/* * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include "config.h"#include "error.h"#include "file.h"#include "file_open.h"#include "internal.h"#include "log.h"#include "mem.h"#include <fcntl.h>#include <sys/stat.h>#if HAVE_UNISTD_H#include <unistd.h>#endif#if HAVE_IO_H#include <io.h>#endif#if HAVE_MMAP#include <sys/mman.h>#elif HAVE_MAPVIEWOFFILE#include <windows.h>#endif typedef struct FileLogContext {    const AVClass *class;    int   log_offset;    void *log_ctx;} FileLogContext; static const AVClass file_log_ctx_class = {    .class_name                = "FILE",    .item_name                 = av_default_item_name,    .option                    = NULL,    .version                   = LIBAVUTIL_VERSION_INT,    .log_level_offset_offset   = offsetof(FileLogContext, log_offset),    .parent_log_context_offset = offsetof(FileLogContext, log_ctx),}; int av_file_map(const char *filename, uint8_t **bufptr, size_t *size,                int log_offset, void *log_ctx){    FileLogContext file_log_ctx = { &file_log_ctx_class, log_offset, log_ctx };    int err, fd = avpriv_open(filename, O_RDONLY);    struct stat st;    av_unused void *ptr;    off_t off_size;    *bufptr = NULL;    *size = 0;     if (fd < 0) {        err = AVERROR(errno);        av_log(&file_log_ctx, AV_LOG_ERROR, "Cannot read file '%s': %s\n", filename, av_err2str(err));        return err;    }     if (fstat(fd, &st) < 0) {        err = AVERROR(errno);        av_log(&file_log_ctx, AV_LOG_ERROR, "Error occurred in fstat(): %s\n", av_err2str(err));        close(fd);        return err;    }     off_size = st.st_size;    if (off_size > SIZE_MAX) {        av_log(&file_log_ctx, AV_LOG_ERROR,               "File size for file '%s' is too big\n", filename);        close(fd);        return AVERROR(EINVAL);    }    *size = off_size;     if (!*size) {        *bufptr = NULL;        goto out;    } #if HAVE_MMAP    ptr = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);    if (ptr == MAP_FAILED) {        err = AVERROR(errno);        av_log(&file_log_ctx, AV_LOG_ERROR, "Error occurred in mmap(): %s\n", av_err2str(err));        close(fd);        *size = 0;        return err;    }    *bufptr = ptr;#elif HAVE_MAPVIEWOFFILE    {        HANDLE mh, fh = (HANDLE)_get_osfhandle(fd);         mh = CreateFileMapping(fh, NULL, PAGE_READONLY, 0, 0, NULL);        if (!mh) {            av_log(&file_log_ctx, AV_LOG_ERROR, "Error occurred in CreateFileMapping()\n");            close(fd);            *size = 0;            return -1;        }         ptr = MapViewOfFile(mh, FILE_MAP_COPY, 0, 0, *size);        CloseHandle(mh);        if (!ptr) {            av_log(&file_log_ctx, AV_LOG_ERROR, "Error occurred in MapViewOfFile()\n");            close(fd);            *size = 0;            return -1;        }         *bufptr = ptr;    }#else    *bufptr = av_malloc(*size);    if (!*bufptr) {        av_log(&file_log_ctx, AV_LOG_ERROR, "Memory allocation error occurred\n");        close(fd);        *size = 0;        return AVERROR(ENOMEM);    }    read(fd, *bufptr, *size);#endif out:    close(fd);    return 0;} void av_file_unmap(uint8_t *bufptr, size_t size){    if (!size || !bufptr)        return;#if HAVE_MMAP    munmap(bufptr, size);#elif HAVE_MAPVIEWOFFILE    UnmapViewOfFile(bufptr);#else    av_free(bufptr);#endif}