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Diffstat (limited to 'src/utils/storage.cc')
| -rw-r--r-- | src/utils/storage.cc | 175 |
1 files changed, 175 insertions, 0 deletions
diff --git a/src/utils/storage.cc b/src/utils/storage.cc new file mode 100644 index 00000000..4db7f302 --- /dev/null +++ b/src/utils/storage.cc @@ -0,0 +1,175 @@ +// Copyright (C) 2010, Gabriel Dos Reis. +// All rights reserved. +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// - Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// +// - Redistributions in binary form must reproduce the above copyright +// notice, this list of conditions and the following disclaimer in +// the documentation and/or other materials provided with the +// distribution. +// +// - Neither the name of The Numerical Algorithms Group Ltd. nor the +// names of its contributors may be used to endorse or promote products +// derived from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS +// IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED +// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A +// PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER +// OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, +// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, +// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR +// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF +// LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING +// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS +// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +#include "openaxiom-c-macros.h" + +#ifdef HAVE_SYS_TYPES_H +# include <sys/types.h> +#endif +#ifdef HAVE_SYS_STAT_H +# include <sys/stat.h> +#endif +#include <sys/types.h> +#ifdef HAVE_FCNTL_H +# include <fcntl.h> +#endif +#ifdef HAVE_UNISTD_H +# include <unistd.h> +#endif +#ifdef HAVE_SYS_MMAN_H +# include <sys/mman.h> +#endif +#ifdef OPENAXIOM_MS_WINDOWS_HOST +# include <windows.h> +#endif +#include <errno.h> +#include <stdlib.h> +#include <string.h> +#include "storage.H" + +namespace OpenAxiom { + // ---------------- + // -- SystemError -- + // ---------------- + SystemError::SystemError(std::string s) : text(s) { } + + SystemError::~SystemError() { } + + const std::string& + SystemError::message() const { + return text; + } + + void + filesystem_error(std::string s) { + throw SystemError(s); + } + + namespace Memory { + // Return storage page allocation unit in byte count. + size_t page_size() { +#if defined(OPENAXIOM_MS_WINDOWS_HOST) + SYSTEM_INFO si = { }; + GetSystemInfo(&si); + return si.dwPageSize; +#elif defined(HAVE_UNISTD_H) + return sysconf(_SC_PAGESIZE); +#else + // Well, we have to return a number. + return 4096; +#endif + } + + // Subroutine of os_acquire_raw_memory. Attempt to acquire + // storage from the host OS. Return null on failure. + static inline Pointer + os_allocate_read_write_raw_memory(size_t nbytes) { +#if defined(OPENAXIOM_MS_WINDOWS_HOST) + return VirtualAlloc(Pointer(), nbytes, + MEM_RESERVE | MEM_COMMIT, PAGE_READWRITE); +#elif defined(HAVE_SYS_MMAN_H) + Pointer p = mmap(Pointer(), nbytes, PROT_READ | PROT_WRITE, + MAP_PRIVATE | OPENAXIOM_MM_ANONYMOUS_MAP_FLAG, + -1, 0); + return p == MAP_FAILED ? Pointer() : p; +#else + return malloc(byte_count); +#endif + } + + Pointer + os_acquire_raw_memory(size_t nbytes) { + Pointer p = os_allocate_read_write_raw_memory(nbytes); + if (p == 0) + throw SystemError("cannot acquire more memory"); + return memset(p, nbytes, 0); + } + + void + os_release_raw_memory(Pointer p, size_t n) { +#if defined(OPENAXIOM_MS_WINDOWS_HOST) + VirtualFree(p, 0, MEM_RELEASE); +#elif defined(HAVE_SYS_MMAN_H) + munmap(p, n); +#else + free(p); +#endif + } + + // ----------------- + // -- FileMapping -- + // ----------------- + FileMapping::FileMapping(std::string path) + : start(), extent() { +#if defined(OPENAXIOM_MS_WINDOWS_HOST) + HANDLE file = CreateFile(path.c_str(), GENERIC_READ, 0, 0, + OPEN_EXISTING, + FILE_ATTRIBUTE_NORMAL, 0); + if (file == INVALID_HANDLE_VALUE) + filesystem_error("could not access file " + path); + HANDLE mapping = CreateFileMapping(file, 0, PAGE_READONLY, 0, 0, 0); + if (mapping == 0) + filesystem_error("could not map file " + path); + start = MapViewOfFile(mapping, FILE_MAP_READ, 0, 0, 0); + extent = GetFileSize(file, 0); + CloseHandle(mapping); + CloseHandle(file); +#elif defined(HAVE_SYS_STAT_H) && defined(HAVE_SYS_MMAN_H) && defined(HAVE_FCNTL_H) + struct stat s; + errno = 0; + if (stat(path.c_str(), &s) < 0) + filesystem_error("could not access file " + path); + else if (!S_ISREG(s.st_mode)) + filesystem_error(path + " is not a regular file"); + int fd = open(path.c_str(), O_RDONLY); + if (fd < 0) + filesystem_error("could not open " + path); + start = mmap(Pointer(), s.st_size, PROT_READ, MAP_PRIVATE, fd, 0); + close(fd); + if (start == MAP_FAILED) + filesystem_error("could not map file " + path); + extent = s.st_size; +#else +# error "Don't know how to map a file on this platform" +#endif // OPENAXIOM_MS_WINDOWS_HOST + } + + FileMapping::~FileMapping() { +#if defined(OPENAXIOM_MS_WINDOWS_HOST) + UnmapViewOfFile(start); +#elif defined(HAVE_SYS_MMAN_H) + munmap(start, extent); +#else +# error "Don't know how to unmap a file on this platform" +#endif + } + } +} |