forked from 0ad/0ad
1381 lines
37 KiB
C++
Executable File
1381 lines
37 KiB
C++
Executable File
// file layer on top of POSIX.
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// provides streaming support and caching.
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//
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// Copyright (c) 2004 Jan Wassenberg
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//
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// This file is free software; you can redistribute it and/or
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// modify it under the terms of the GNU General Public License as
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// published by the Free Software Foundation; either version 2 of the
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// License, or (at your option) any later version.
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//
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// This file is distributed in the hope that it will be useful, but
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// WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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// General Public License for more details.
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//
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// Contact info:
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// Jan.Wassenberg@stud.uni-karlsruhe.de
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// http://www.stud.uni-karlsruhe.de/~urkt/
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#include "precompiled.h"
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#include "lib.h"
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#include "../res.h"
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#include "file.h"
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#include "detect.h"
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#include "adts.h"
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#include "sysdep/sysdep.h"
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#include "byte_order.h"
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#include "lib/allocators.h"
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#include <vector>
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#include <algorithm>
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#include <string>
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// block := power-of-two sized chunk of a file.
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// all transfers are expanded to naturally aligned, whole blocks
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// (this makes caching parts of files feasible; it is also much faster
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// for some aio implementations, e.g. wposix).
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const size_t BLOCK_SIZE_LOG2 = 16; // 2**16 = 64 KiB
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const size_t BLOCK_SIZE = 1ul << BLOCK_SIZE_LOG2;
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const size_t SECTOR_SIZE = 4096;
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// reasonable guess. if too small, aio will do alignment.
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// rationale for aio, instead of only using mmap:
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// - parallelism: instead of just waiting for the transfer to complete,
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// other work can be done in the meantime.
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// example: decompressing from a Zip archive is practically free,
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// because we inflate one block while reading the next.
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// - throughput: with aio, the drive always has something to do, as opposed
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// to read requests triggered by the OS for mapped files, which come
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// in smaller chunks. this leads to much higher transfer rates.
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// - memory: when used with VFS, aio makes better use of a file cache.
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// data is generally compressed in an archive. a cache should store the
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// decompressed and decoded (e.g. TGA colour swapping) data; mmap would
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// keep the original, compressed data in memory, which doesn't help.
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// we bypass the OS file cache via aio, and store partial blocks here (*);
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// higher level routines will cache the actual useful data.
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// * requests for part of a block are usually followed by another.
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// convenience "class" that simplifies successively appending a filename to
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// its parent directory. this avoids needing to allocate memory and calling
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// strlen/strcat. used by wdetect and dir_next_ent.
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// we want to maintain C compatibility, so this isn't a C++ class.
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// write the given directory path into our buffer and set end/chars_left
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// accordingly. <dir> need and should not end with a directory separator.
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int pp_set_dir(PathPackage* pp, const char* dir)
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{
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// note: use / instead of DIR_SEP because pp->path is portable.
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const int len = snprintf(pp->path, ARRAY_SIZE(pp->path), "%s/", dir);
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// (need len below and must return an error code, not -1)
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if(len < 0)
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CHECK_ERR(ERR_PATH_LENGTH);
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pp->end = pp->path+len;
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pp->chars_left = ARRAY_SIZE(pp->path)-len;
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// check if <dir> actually did end with '/' (this will cause problems
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// when attempting to vfs_open the file).
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if(len >= 2) // protect against underrun
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debug_assert(pp->end[-2] != '/' && pp->end[-2] != DIR_SEP);
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return 0;
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}
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// append the given filename to the directory established by the last
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// pp_set_dir on this package. the whole path is accessible at pp->path.
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int pp_append_file(PathPackage* pp, const char* fn)
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{
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CHECK_ERR(strcpy_s(pp->end, pp->chars_left, fn));
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return 0;
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}
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//-----------------------------------------------------------------------------
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// is s2 a subpath of s1, or vice versa? used by VFS and wdir_watch.
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// works for portable and native paths.
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bool file_is_subpath(const char* s1, const char* s2)
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{
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// make sure s1 is the shorter string
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if(strlen(s1) > strlen(s2))
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std::swap(s1, s2);
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int c1 = 0, last_c1, c2;
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for(;;)
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{
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last_c1 = c1;
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c1 = *s1++, c2 = *s2++;
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// end of s1 reached:
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if(c1 == '\0')
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{
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// s1 matched s2 up until:
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if((c2 == '\0') || // its end (i.e. they're equal length)
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(c2 == '/' || c2 == DIR_SEP) || // start of next component
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(last_c1 == '/' || last_c1 == DIR_SEP)) // ", but both have a trailing slash
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// => is subpath
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return true;
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}
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// mismatch => is not subpath
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if(c1 != c2)
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return false;
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}
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}
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enum Conversion
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{
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TO_NATIVE,
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TO_PORTABLE
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};
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static int convert_path(char* dst, const char* src, Conversion conv = TO_NATIVE)
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{
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// DIR_SEP is assumed to be a single character!
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const char* s = src;
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char* d = dst;
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char from = DIR_SEP, to = '/';
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if(conv == TO_NATIVE)
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from = '/', to = DIR_SEP;
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size_t len = 0;
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for(;;)
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{
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len++;
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if(len >= PATH_MAX)
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CHECK_ERR(ERR_PATH_LENGTH);
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char c = *s++;
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if(c == from)
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c = to;
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*d++ = c;
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// end of string - done
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if(c == '\0')
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return 0;
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}
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}
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// set by file_set_root_dir
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static char n_root_dir[PATH_MAX];
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static size_t n_root_dir_len;
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// return the native equivalent of the given relative portable path
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// (i.e. convert all '/' to the platform's directory separator)
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// makes sure length < PATH_MAX.
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int file_make_native_path(const char* path, char* n_path)
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{
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return convert_path(n_path, path, TO_NATIVE);
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}
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// return the portable equivalent of the given relative native path
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// (i.e. convert the platform's directory separators to '/')
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// makes sure length < PATH_MAX.
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int file_make_portable_path(const char* n_path, char* path)
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{
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return convert_path(path, n_path, TO_PORTABLE);
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}
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// return the native equivalent of the given portable path
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// (i.e. convert all '/' to the platform's directory separator).
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// also prepends current directory => n_full_path is absolute.
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// makes sure length < PATH_MAX.
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int file_make_full_native_path(const char* path, char* n_full_path)
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{
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debug_assert(path != n_full_path); // doesn't work in-place
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strcpy_s(n_full_path, PATH_MAX, n_root_dir);
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return convert_path(n_full_path+n_root_dir_len, path, TO_NATIVE);
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}
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// return the portable equivalent of the given relative native path
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// (i.e. convert the platform's directory separators to '/')
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// n_full_path is absolute; if it doesn't match the current dir, fail.
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// (note: portable paths are always relative to the file root dir).
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// makes sure length < PATH_MAX.
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int file_make_full_portable_path(const char* n_full_path, char* path)
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{
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debug_assert(path != n_full_path); // doesn't work in-place
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if(strncmp(n_full_path, n_root_dir, n_root_dir_len) != 0)
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return -1;
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return convert_path(path, n_full_path+n_root_dir_len, TO_PORTABLE);
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}
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// establish the root directory from <rel_path>, which is treated as
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// relative to the executable's directory (determined via argv[0]).
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// all relative file paths passed to this module will be based from
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// this root dir.
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//
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// example: executable in "$install_dir/system"; desired root dir is
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// "$install_dir/data" => rel_path = "../data".
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//
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// argv[0] is necessary because the current directory is unknown at startup
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// (e.g. it isn't set when invoked via batch file), and this is the
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// easiest portable way to find our install directory.
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//
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// can only be called once, by design (see below). rel_path is trusted.
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int file_set_root_dir(const char* argv0, const char* rel_path)
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{
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const char* msg = 0;
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// security check: only allow attempting to chdir once, so that malicious
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// code cannot circumvent the VFS checks that disallow access to anything
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// above the current directory (set here).
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// this routine is called early at startup, so any subsequent attempts
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// are likely bogus.
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static bool already_attempted;
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if(already_attempted)
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{
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msg = "called more than once";
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goto fail;
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}
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already_attempted = true;
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{
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// get full path to executable
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char n_path[PATH_MAX];
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// .. first try safe, but system-dependent version
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if(get_executable_name(n_path, PATH_MAX) < 0)
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{
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// .. failed; use argv[0]
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if(!realpath(argv0, n_path))
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goto fail;
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}
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// make sure it's valid
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if(access(n_path, X_OK) < 0)
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goto fail;
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// strip executable name, append rel_path, convert to native
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char* fn = strrchr(n_path, DIR_SEP);
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if(!fn)
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{
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msg = "realpath returned an invalid path?";
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goto fail;
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}
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RETURN_ERR(file_make_native_path(rel_path, fn+1));
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// get actual root dir - previous n_path may include ".."
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// (slight optimization, speeds up path lookup)
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if(!realpath(n_path, n_root_dir))
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goto fail;
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// .. append DIR_SEP to simplify code that uses n_root_dir
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// (note: already 0-terminated, since it's static)
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n_root_dir_len = strlen(n_root_dir)+1; // +1 for trailing DIR_SEP
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n_root_dir[n_root_dir_len-1] = DIR_SEP;
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return 0;
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}
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fail:
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debug_warn("failed");
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if(msg)
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{
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debug_printf("%s: %s\n", __func__, msg);
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return -1;
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}
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return -errno;
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}
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//-----------------------------------------------------------------------------
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// layer on top of POSIX opendir/readdir/closedir that handles
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// portable -> native path conversion, ignores non-file/directory entries,
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// and additionally returns the file status (size and mtime).
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//
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// all functions return an int error code to allow CHECK_ERR.
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// rationale: see DirIterator definition in header.
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struct DirIterator_
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{
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DIR* os_dir;
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// to support stat(), we need to either chdir or store the complete path.
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// the former is unacceptable because it isn't thread-safe. therefore,
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// we latch dir_open's path and append entry name every dir_next_ent call.
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// this is also the storage to which DirEnt.name points!
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// PathPackage avoids repeated memory allocs and strlen() overhead.
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PathPackage pp;
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};
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cassert(sizeof(DirIterator_) <= sizeof(DirIterator));
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// prepare to iterate (once) over entries in the given directory.
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// returns a negative error code or 0 on success, in which case <d> is
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// ready for subsequent dir_next_ent calls and must be freed via dir_close.
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int dir_open(const char* P_path, DirIterator* d_)
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{
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DirIterator_* d = (DirIterator_*)d_;
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char n_path[PATH_MAX];
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// HACK: allow calling with a full (absolute) native path.
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// (required by wdetect).
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#if OS_WIN
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if(P_path[1] == ':' && P_path[2] == '\\')
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strcpy_s(n_path, ARRAY_SIZE(n_path), P_path);
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else
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#endif
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{
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// note: copying to n_path and then pp.path is inefficient but
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// more clear/robust. this is only called a few hundred times anyway.
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RETURN_ERR(file_make_full_native_path(P_path, n_path));
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}
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d->os_dir = opendir(n_path);
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if(!d->os_dir)
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{
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int err;
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switch(errno)
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{
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case ENOMEM:
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err = ERR_NO_MEM;
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break;
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case ENOENT:
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err = ERR_PATH_NOT_FOUND;
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break;
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default:
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err = -1;
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break;
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}
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CHECK_ERR(err);
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}
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RETURN_ERR(pp_set_dir(&d->pp, n_path));
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return 0;
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}
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// return ERR_DIR_END if all entries have already been returned once,
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// another negative error code, or 0 on success, in which case <ent>
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// describes the next (order is unspecified) directory entry.
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int dir_next_ent(DirIterator* d_, DirEnt* ent)
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{
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DirIterator_* d = (DirIterator_*)d_;
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get_another_entry:
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errno = 0;
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struct dirent* os_ent = readdir(d->os_dir);
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if(!os_ent)
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{
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if(errno)
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debug_warn("readdir failed");
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return ERR_DIR_END;
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}
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// copy os_ent.name[]; we need it for stat() #if !OS_WIN and
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// return it as ent.name (since os_ent.name[] is volatile).
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pp_append_file(&d->pp, os_ent->d_name);
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const char* name = d->pp.end;
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// get file information (mode, size, mtime)
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struct stat s;
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#if OS_WIN
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// .. wposix readdir has enough information to return dirent
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// status directly (much faster than calling stat).
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CHECK_ERR(readdir_stat_np(d->os_dir, &s));
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#else
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// .. call regular stat().
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// we need the full pathname for this. don't use vfs_path_append because
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// it would unnecessarily call strlen.
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CHECK_ERR(stat(d->pp.path, &s));
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#endif
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// skip "undesirable" entries that POSIX readdir returns:
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if(S_ISDIR(s.st_mode))
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{
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// .. dummy directory entries ("." and "..")
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if(name[0] == '.' && (name[1] == '\0' || (name[1] == '.' && name[2] == '\0')))
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goto get_another_entry;
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s.st_size = -1; // our way of indicating it's a directory
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}
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// .. neither dir nor file
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else if(!S_ISREG(s.st_mode))
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goto get_another_entry;
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ent->size = s.st_size;
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ent->mtime = s.st_mtime;
|
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ent->name = name;
|
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return 0;
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}
|
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|
|
|
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// indicate the directory iterator is no longer needed; all resources it
|
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// held are freed.
|
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int dir_close(DirIterator* d_)
|
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{
|
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DirIterator_* d = (DirIterator_*)d_;
|
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WARN_ERR(closedir(d->os_dir));
|
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return 0;
|
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}
|
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|
|
|
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static bool dirent_less(const DirEnt* d1, const DirEnt* d2)
|
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{
|
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return strcmp(d1->name, d2->name) < 0;
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}
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|
|
|
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// call <cb> for each file and subdirectory in <dir> (alphabetical order),
|
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// passing the entry name (not full path!), stat info, and <user>.
|
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//
|
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// first builds a list of entries (sorted) and remembers if an error occurred.
|
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// if <cb> returns non-zero, abort immediately and return that; otherwise,
|
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// return first error encountered while listing files, or 0 on success.
|
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//
|
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// rationale:
|
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// this makes file_enum and zip_enum slightly incompatible, since zip_enum
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// returns the full path. that's necessary because VFS zip_cb
|
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// has no other way of determining what VFS dir a Zip file is in,
|
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// since zip_enum enumerates all files in the archive (not only those
|
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// in a given dir). no big deal though, since add_ent has to
|
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// special-case Zip files anyway.
|
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// the advantage here is simplicity, and sparing callbacks the trouble
|
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// of converting from/to native path (we just give 'em the dirent name).
|
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int file_enum(const char* P_path, const FileCB cb, const uintptr_t user)
|
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{
|
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// pointer to DirEnt: faster sorting, but more allocs.
|
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typedef std::vector<const DirEnt*> DirEnts;
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typedef DirEnts::const_iterator DirEntCIt;
|
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typedef DirEnts::reverse_iterator DirEntRIt;
|
|
// all entries are enumerated (adding to this container),
|
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// std::sort-ed, then all passed to cb.
|
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DirEnts dirents;
|
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dirents.reserve(125); // preallocate for efficiency
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|
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int stat_err = 0; // first error encountered by stat()
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int cb_err = 0; // first error returned by cb
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|
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DirIterator d;
|
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CHECK_ERR(dir_open(P_path, &d));
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|
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DirEnt ent;
|
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for(;;) // instead of while() to avoid warnings
|
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{
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int ret = dir_next_ent(&d, &ent);
|
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if(ret == ERR_DIR_END)
|
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break;
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if(!stat_err)
|
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stat_err = ret;
|
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|
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const size_t size = sizeof(DirEnt)+strlen(ent.name)+1;
|
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DirEnt* p_ent = (DirEnt*)malloc(size);
|
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if(!p_ent)
|
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{
|
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stat_err = ERR_NO_MEM;
|
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goto fail;
|
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}
|
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p_ent->size = ent.size;
|
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p_ent->mtime = ent.mtime;
|
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p_ent->name = (const char*)p_ent + sizeof(DirEnt);
|
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strcpy((char*)p_ent->name, ent.name); // safe
|
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dirents.push_back(p_ent);
|
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}
|
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|
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std::sort(dirents.begin(), dirents.end(), dirent_less);
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|
|
|
// call back for each entry (now sorted)
|
|
{
|
|
struct stat s;
|
|
memset(&s, 0, sizeof(s));
|
|
for(DirEntCIt it = dirents.begin(); it != dirents.end(); ++it)
|
|
{
|
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const DirEnt* ent = *it;
|
|
s.st_mode = (ent->size == -1)? S_IFDIR : S_IFREG;
|
|
s.st_size = ent->size;
|
|
s.st_mtime = ent->mtime;
|
|
int ret = cb(ent->name, &s, user);
|
|
if(ret != 0)
|
|
{
|
|
cb_err = ret; // first error (since we now abort)
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
fail:
|
|
WARN_ERR(dir_close(&d));
|
|
|
|
// free all memory (can't do in loop above because it may be aborted).
|
|
for(DirEntRIt rit = dirents.rbegin(); rit != dirents.rend(); ++rit)
|
|
free((void*)(*rit));
|
|
|
|
if(cb_err != 0)
|
|
return cb_err;
|
|
return stat_err;
|
|
}
|
|
|
|
|
|
// get file information. output param is zeroed on error.
|
|
int file_stat(const char* path, struct stat* s)
|
|
{
|
|
memset(s, 0, sizeof(struct stat));
|
|
|
|
char n_path[PATH_MAX+1];
|
|
CHECK_ERR(file_make_full_native_path(path, n_path));
|
|
|
|
return stat(n_path, s);
|
|
}
|
|
|
|
|
|
///////////////////////////////////////////////////////////////////////////////
|
|
//
|
|
// file open/close
|
|
// stores information about file (e.g. size) in File struct
|
|
//
|
|
///////////////////////////////////////////////////////////////////////////////
|
|
|
|
|
|
// interface rationale:
|
|
// - this module depends on the handle manager for IO management,
|
|
// but should be useable without the VFS (even if they are designed
|
|
// to work together).
|
|
// - allocating a Handle for the file info would solve several problems
|
|
// (see below), but we don't want to allocate 2..3 (VFS, file, Zip file)
|
|
// for every file opened - that'd add up quickly.
|
|
// the Files are always freed at exit though, since they're part of
|
|
// VFile handles in the VFS.
|
|
// - we want the VFS open logic to be triggered on file invalidate
|
|
// (if the dev. file is deleted, we should use what's in the archives).
|
|
// we don't want to make this module depend on VFS, so we don't
|
|
// have access to the file location DB; VFS needs to allocate the handle.
|
|
// - no problem exposing our internals via File struct -
|
|
// we're only used by the VFS and Zip modules. don't bother making
|
|
// an opaque struct - that'd have to be kept in sync with the real thing.
|
|
// - when Zip opens its archives via file_open, a handle isn't needed -
|
|
// the Zip module hides its File struct (required to close the file),
|
|
// and the Handle approach doesn't guard against some idiot calling
|
|
// close(our_fd_value) directly, either.
|
|
|
|
|
|
int file_validate(const File* f)
|
|
{
|
|
if(!f)
|
|
return ERR_INVALID_PARAM;
|
|
else if(f->fd < 0)
|
|
return -2;
|
|
// mapped but refcount is invalid
|
|
else if((f->mapping != 0) ^ (f->map_refs != 0))
|
|
return -3;
|
|
// fn_hash not set
|
|
#ifndef NDEBUG
|
|
else if(!f->fn_hash)
|
|
return -4;
|
|
#endif
|
|
|
|
return 0;
|
|
}
|
|
|
|
#define CHECK_FILE(f) CHECK_ERR(file_validate(f))
|
|
|
|
|
|
int file_open(const char* p_fn, const uint flags, File* f)
|
|
{
|
|
// zero output param in case we fail below.
|
|
memset(f, 0, sizeof(*f));
|
|
|
|
if(flags > FILE_FLAG_MAX)
|
|
return ERR_INVALID_PARAM;
|
|
|
|
char n_fn[PATH_MAX];
|
|
RETURN_ERR(file_make_full_native_path(p_fn, n_fn));
|
|
|
|
// don't stat if opening for writing - the file may not exist yet
|
|
off_t size = 0;
|
|
|
|
int oflag = O_RDONLY;
|
|
if(flags & FILE_WRITE)
|
|
oflag = O_WRONLY|O_CREAT|O_TRUNC;
|
|
// read access requested
|
|
else
|
|
{
|
|
// get file size
|
|
struct stat s;
|
|
if(stat(n_fn, &s) < 0)
|
|
return ERR_FILE_NOT_FOUND;
|
|
size = s.st_size;
|
|
|
|
// note: despite increased overhead, the AIO read method is still
|
|
// significantly faster, even with small files.
|
|
// we therefore don't automatically disable AIO.
|
|
// notes:
|
|
// - up to 32KB can be read by one SCSI request.
|
|
// - flags are stored below and will influence file_io.
|
|
//if(size <= 32*KiB)
|
|
// flags |= FILE_NO_AIO;
|
|
|
|
// make sure <n_fn> is a regular file
|
|
if(!S_ISREG(s.st_mode))
|
|
return ERR_NOT_FILE;
|
|
}
|
|
|
|
#if OS_WIN
|
|
if(flags & FILE_TEXT)
|
|
oflag |= O_TEXT_NP;
|
|
else
|
|
oflag |= O_BINARY_NP;
|
|
|
|
// if AIO is disabled (at user's behest or because the file is small),
|
|
// so inform wposix.
|
|
if(flags & FILE_NO_AIO)
|
|
oflag |= O_NO_AIO_NP;
|
|
#endif
|
|
|
|
int fd = open(n_fn, oflag, S_IRWXO|S_IRWXU|S_IRWXG);
|
|
if(fd < 0)
|
|
return ERR_FILE_ACCESS;
|
|
|
|
f->flags = flags;
|
|
f->size = size;
|
|
f->fn_hash = fnv_hash(n_fn); // copy filename instead?
|
|
f->mapping = 0;
|
|
f->map_refs = 0;
|
|
f->fd = fd;
|
|
CHECK_FILE(f);
|
|
return 0;
|
|
}
|
|
|
|
|
|
int file_close(File* f)
|
|
{
|
|
CHECK_FILE(f);
|
|
|
|
// make sure the mapping is actually freed,
|
|
// regardless of how many references remain.
|
|
if(f->map_refs > 1)
|
|
f->map_refs = 1;
|
|
if(f->mapping) // only free if necessary (unmap complains if not mapped)
|
|
file_unmap(f);
|
|
|
|
// return final file size (required by VFS after writing files).
|
|
// this is much easier than updating when writing, because we'd have
|
|
// to add accounting code to both (sync and async) paths.
|
|
f->size = lseek(f->fd, 0, SEEK_END);
|
|
|
|
// (check fd to avoid BoundsChecker warning about invalid close() param)
|
|
if(f->fd != -1)
|
|
{
|
|
close(f->fd);
|
|
f->fd = -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
///////////////////////////////////////////////////////////////////////////////
|
|
//
|
|
// async I/O
|
|
//
|
|
///////////////////////////////////////////////////////////////////////////////
|
|
|
|
|
|
// rationale:
|
|
// asynchronous IO routines don't cache; they're just a thin AIO wrapper.
|
|
// it's taken care of by file_io, which splits transfers into blocks
|
|
// and keeps temp buffers in memory (not user-allocated, because they
|
|
// might pull the rug out from under us at any time).
|
|
//
|
|
// doing so here would be more complicated: would have to handle "forwarding",
|
|
// i.e. recognizing that the desired block has been issued, but isn't yet
|
|
// complete. file_io also knows more about whether a block should be cached.
|
|
//
|
|
// disadvantages:
|
|
// - streamed data will always be read from disk. no problem, because
|
|
// such data (e.g. music, long speech) is unlikely to be used again soon.
|
|
// - prefetching (issuing the next few blocks from an archive during idle
|
|
// time, so that future out-of-order reads don't need to seek) isn't
|
|
// possible in the background (unless via thread, but that's discouraged).
|
|
// the utility is questionable, though: how to prefetch so as not to delay
|
|
// real IOs? can't determine "idle time" without completion notification,
|
|
// which is hard.
|
|
// we could get the same effect by bridging small gaps in file_io,
|
|
// and rearranging files in the archive in order of access.
|
|
|
|
|
|
static Pool aiocb_pool;
|
|
|
|
static inline void aiocb_pool_init()
|
|
{
|
|
(void)pool_create(&aiocb_pool, 32*sizeof(aiocb), sizeof(aiocb));
|
|
}
|
|
|
|
static inline void aiocb_pool_shutdown()
|
|
{
|
|
(void)pool_destroy(&aiocb_pool);
|
|
}
|
|
|
|
static inline aiocb* aiocb_pool_alloc()
|
|
{
|
|
ONCE(aiocb_pool_init());
|
|
return (aiocb*)pool_alloc(&aiocb_pool);
|
|
}
|
|
|
|
static inline void aiocb_pool_free(void* cb)
|
|
{
|
|
pool_free(&aiocb_pool, cb);
|
|
}
|
|
|
|
|
|
// starts transferring to/from the given buffer.
|
|
// no attempt is made at aligning or padding the transfer.
|
|
int file_io_issue(File* f, off_t ofs, size_t size, void* p, FileIo* io)
|
|
{
|
|
// zero output param in case we fail below.
|
|
memset(io, 0, sizeof(FileIo));
|
|
|
|
debug_printf("FILE| issue ofs=%d size=%d\n", ofs, size);
|
|
|
|
|
|
//
|
|
// check params
|
|
//
|
|
|
|
CHECK_FILE(f);
|
|
|
|
if(!size || !p || !io)
|
|
return ERR_INVALID_PARAM;
|
|
|
|
const bool is_write = (f->flags & FILE_WRITE) != 0;
|
|
|
|
// cut off at EOF.
|
|
if(!is_write)
|
|
{
|
|
// avoid min() due to type conversion warnings.
|
|
const off_t bytes_left = f->size - ofs;
|
|
if(bytes_left < 0)
|
|
{
|
|
debug_warn("EOF");
|
|
return ERR_EOF;
|
|
}
|
|
if((off_t)size > bytes_left)
|
|
size = (size_t)bytes_left;
|
|
// guaranteed to fit, since size was > bytes_left
|
|
}
|
|
|
|
|
|
// (we can't store the whole aiocb directly - glibc's version is
|
|
// 144 bytes large)
|
|
aiocb* cb = aiocb_pool_alloc();
|
|
io->cb = cb;
|
|
if(!cb)
|
|
return ERR_NO_MEM;
|
|
memset(cb, 0, sizeof(aiocb));
|
|
|
|
// send off async read/write request
|
|
cb->aio_lio_opcode = is_write? LIO_WRITE : LIO_READ;
|
|
cb->aio_buf = p;
|
|
cb->aio_fildes = f->fd;
|
|
cb->aio_offset = ofs;
|
|
cb->aio_nbytes = size;
|
|
debug_printf("FILE| issue2 io=%p nbytes=%d\n", io, cb->aio_nbytes);
|
|
int err = lio_listio(LIO_NOWAIT, &cb, 1, (struct sigevent*)0);
|
|
if(err < 0)
|
|
{
|
|
debug_printf("lio_listio: %d, %d[%s]\n", err, errno, strerror(errno));
|
|
file_io_discard(io);
|
|
return err;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
// indicates if the IO referenced by <io> has completed.
|
|
// return value: 0 if pending, 1 if complete, < 0 on error.
|
|
int file_io_has_completed(FileIo* io)
|
|
{
|
|
aiocb* cb = (aiocb*)io->cb;
|
|
int ret = aio_error(cb);
|
|
if(ret == EINPROGRESS)
|
|
return 0;
|
|
if(ret == 0)
|
|
return 1;
|
|
|
|
debug_warn("unexpected aio_error return");
|
|
return -1;
|
|
}
|
|
|
|
|
|
int file_io_wait(FileIo* io, void*& p, size_t& size)
|
|
{
|
|
debug_printf("FILE| wait io=%p\n", io);
|
|
|
|
// zero output params in case something (e.g. H_DEREF) fails.
|
|
p = 0;
|
|
size = 0;
|
|
|
|
aiocb* cb = (aiocb*)io->cb;
|
|
|
|
// wait for transfer to complete.
|
|
const aiocb** cbs = (const aiocb**)&cb; // pass in an "array"
|
|
while(aio_error(cb) == EINPROGRESS)
|
|
aio_suspend(cbs, 1, (timespec*)0); // wait indefinitely
|
|
|
|
// query number of bytes transferred (-1 if the transfer failed)
|
|
const ssize_t bytes_transferred = aio_return(cb);
|
|
debug_printf("FILE| bytes_transferred=%d aio_nbytes=%d\n", bytes_transferred, cb->aio_nbytes);
|
|
// (size was clipped to EOF in file_io => this is an actual IO error)
|
|
if(bytes_transferred < (ssize_t)cb->aio_nbytes)
|
|
return ERR_IO;
|
|
|
|
p = (void*)cb->aio_buf; // cast from volatile void*
|
|
size = bytes_transferred;
|
|
return 0;
|
|
}
|
|
|
|
|
|
int file_io_discard(FileIo* io)
|
|
{
|
|
memset(io->cb, 0, sizeof(aiocb));
|
|
// discourage further use.
|
|
aiocb_pool_free(io->cb);
|
|
io->cb = 0;
|
|
return 0;
|
|
}
|
|
|
|
|
|
int file_io_validate(const FileIo* io)
|
|
{
|
|
const aiocb* cb = (const aiocb*)io->cb;
|
|
// >= 0x100 is not necessarily bogus, but suspicious.
|
|
// this also catches negative values.
|
|
if((uint)cb->aio_fildes >= 0x100)
|
|
return -2;
|
|
if(debug_is_pointer_bogus((void*)cb->aio_buf))
|
|
return -3;
|
|
if(cb->aio_lio_opcode != LIO_WRITE && cb->aio_lio_opcode != LIO_READ && cb->aio_lio_opcode != LIO_NOP)
|
|
return -4;
|
|
// all other aiocb fields have no invariants we could check.
|
|
return 0;
|
|
}
|
|
|
|
|
|
///////////////////////////////////////////////////////////////////////////////
|
|
|
|
|
|
|
|
ssize_t lowio(int fd, bool is_write, off_t ofs, size_t size, void* buf)
|
|
{
|
|
lseek(fd, ofs, SEEK_SET);
|
|
|
|
if(is_write)
|
|
return write(fd, buf, size);
|
|
else
|
|
return read (fd, buf, size);
|
|
}
|
|
|
|
|
|
|
|
|
|
// L3 cache: intended to cache raw compressed data, since files aren't aligned
|
|
// in the archive; alignment code would force a read of the whole block,
|
|
// which would be a slowdown unless we keep them in memory.
|
|
//
|
|
// keep out of async code (although extra work for sync: must not issue/wait
|
|
// if was cached) to simplify things. disadvantage: problems if same block
|
|
// is issued twice, before the first call completes (via wait_io).
|
|
// that won't happen though unless we have threaded file_ios =>
|
|
// rare enough not to worry about performance.
|
|
//
|
|
// since sync code allocates the (temp) buffer, it's guaranteed
|
|
// to remain valid.
|
|
//
|
|
|
|
|
|
|
|
// create an id for use with the Cache that uniquely identifies
|
|
// the block from the file <fn_hash> starting at <ofs> (aligned).
|
|
static u64 block_make_id(const u32 fn_hash, const off_t ofs)
|
|
{
|
|
// id format: filename hash | block number
|
|
// 63 32 31 0
|
|
//
|
|
// we assume the hash (currently: FNV) is unique for all filenames.
|
|
// chance of a collision is tiny, and a build tool will ensure
|
|
// filenames in the VFS archives are safe.
|
|
//
|
|
// block_num will always fit in 32 bits (assuming maximum file size
|
|
// = 2^32 * BLOCK_SIZE = 2^48 -- plenty); we check this, but don't
|
|
// include a workaround. we could return 0, and the caller would have
|
|
// to allocate their own buffer, but don't bother.
|
|
|
|
// make sure block_num fits in 32 bits
|
|
const size_t block_num = ofs / BLOCK_SIZE;
|
|
debug_assert(block_num <= 0xffffffff);
|
|
|
|
u64 id = fn_hash; // careful, don't shift a u32 32 bits left
|
|
id <<= 32;
|
|
id |= block_num;
|
|
return id;
|
|
}
|
|
|
|
|
|
typedef std::pair<u64, void*> BlockCacheEntry;
|
|
typedef std::map<u64, void*> BlockCache;
|
|
typedef BlockCache::iterator BlockIt;
|
|
static BlockCache block_cache;
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
struct IOSlot
|
|
{
|
|
FileIo io;
|
|
void* temp_buf;
|
|
|
|
u64 block_id;
|
|
// needed so that we can add the block to the cache when
|
|
// its IO is complete. if we add it when issuing, we'd no longer be
|
|
// thread-safe: someone else might find it in the cache before its
|
|
// transfer has completed. don't want to add an "is_complete" flag,
|
|
// because that'd be hard to update (on every wait_io).
|
|
|
|
void* cached_block;
|
|
// != 0 <==> data coming from cache and no IO issued.
|
|
|
|
|
|
// given buffer
|
|
// given buffer, will copy from cache
|
|
// temp buffer allocated here
|
|
// temp buffer taken from cache
|
|
};
|
|
|
|
|
|
// don't just use operator[], so that block_cache isn't cluttered
|
|
// with IDs associated with 0 (blocks that wouldn't be cached anyway).
|
|
static void* block_find(u64 block_id)
|
|
{
|
|
BlockIt it = block_cache.find(block_id);
|
|
if(it == block_cache.end())
|
|
return 0;
|
|
return it->second;
|
|
}
|
|
|
|
|
|
static void block_add(u64 block_id, void* block)
|
|
{
|
|
if(block_find(block_id))
|
|
debug_warn("already in cache");
|
|
else
|
|
block_cache[block_id] = block;
|
|
}
|
|
|
|
|
|
static ssize_t block_issue(File* f, IOSlot* slot, const off_t issue_ofs, void* buf)
|
|
{
|
|
memset(slot, 0, sizeof(IOSlot));
|
|
|
|
ssize_t issue_size = BLOCK_SIZE;
|
|
|
|
// check if in cache
|
|
slot->block_id = block_make_id(f->fn_hash, issue_ofs);
|
|
slot->cached_block = block_find(slot->block_id);
|
|
if(slot->cached_block)
|
|
goto skip_issue;
|
|
|
|
//debug_printf("%x miss\n", issue_ofs);
|
|
|
|
// allocate temp buffer
|
|
if(!buf)
|
|
buf = slot->temp_buf = mem_alloc(BLOCK_SIZE, BLOCK_SIZE);
|
|
|
|
|
|
// if using buffer, set position in it; otherwise, use temp buffer
|
|
CHECK_ERR(file_io_issue(f, issue_ofs, BLOCK_SIZE, buf, &slot->io));
|
|
|
|
skip_issue:
|
|
|
|
return issue_size;
|
|
}
|
|
|
|
|
|
static void block_shutdown()
|
|
{
|
|
for(BlockIt it = block_cache.begin(); it != block_cache.end(); ++it)
|
|
mem_free(it->second);
|
|
}
|
|
|
|
|
|
|
|
// remove all blocks loaded from the file <fn>. used when reloading the file.
|
|
int file_invalidate_cache(const char* fn)
|
|
{
|
|
// convert to native path to match fn_hash set by file_open
|
|
char n_fn[PATH_MAX];
|
|
file_make_full_native_path(fn, n_fn);
|
|
|
|
const u32 fn_hash = fnv_hash(fn);
|
|
// notes:
|
|
// - don't use remove_if, because std::pair doesn't have operator=.
|
|
// - erasing elements during loop is ok because map iterators aren't
|
|
// invalidated.
|
|
for(BlockIt it = block_cache.begin(); it != block_cache.end(); ++it)
|
|
if((it->first >> 32) == fn_hash)
|
|
block_cache.erase(it);
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
|
|
// the underlying aio implementation likes buffer and offset to be
|
|
// sector-aligned; if not, the transfer goes through an align buffer,
|
|
// and requires an extra memcpy2.
|
|
//
|
|
// if the user specifies an unaligned buffer, there's not much we can
|
|
// do - we can't assume the buffer contains padding. therefore,
|
|
// callers should let us allocate the buffer if possible.
|
|
//
|
|
// if ofs misalign = buffer, only the first and last blocks will need
|
|
// to be copied by aio, since we read up to the next block boundary.
|
|
// otherwise, everything will have to be copied; at least we split
|
|
// the read into blocks, so aio's buffer won't have to cover the
|
|
// whole file.
|
|
|
|
|
|
|
|
// transfer <size> bytes, starting at <ofs>, to/from the given file.
|
|
// (read or write access was chosen at file-open time).
|
|
//
|
|
// if non-NULL, <cb> is called for each block transferred, passing <ctx>.
|
|
// it returns how much data was actually transferred, or a negative error
|
|
// code (in which case we abort the transfer and return that value).
|
|
// the callback mechanism is useful for user progress notification or
|
|
// processing data while waiting for the next I/O to complete
|
|
// (quasi-parallel, without the complexity of threads).
|
|
//
|
|
// return number of bytes transferred (see above), or a negative error code.
|
|
ssize_t file_io(File* f, off_t data_ofs, size_t data_size, void* data_buf,
|
|
FileIOCB cb, uintptr_t ctx) // optional
|
|
{
|
|
debug_printf("FILE| io: fd=%d size=%d ofs=%d\n", f->fd, data_size, data_ofs);
|
|
|
|
CHECK_FILE(f);
|
|
|
|
const bool is_write = !!(f->flags & FILE_WRITE);
|
|
const bool no_aio = !!(f->flags & FILE_NO_AIO);
|
|
|
|
// when reading:
|
|
if(!is_write)
|
|
{
|
|
// cut data_size off at EOF
|
|
const ssize_t bytes_left = f->size - data_ofs;
|
|
if(bytes_left < 0)
|
|
return ERR_EOF;
|
|
data_size = MIN(data_size, (size_t)bytes_left);
|
|
}
|
|
|
|
bool temp = (data_buf == 0);
|
|
|
|
// sanity checks:
|
|
// .. temp blocks requested AND
|
|
// (not reading OR using lowio OR no callback)
|
|
if(temp && (is_write || no_aio || !cb))
|
|
{
|
|
debug_warn("invalid parameter");
|
|
return ERR_INVALID_PARAM;
|
|
}
|
|
|
|
|
|
// only align if we allocate the buffer and in AIO mode
|
|
const bool do_align = temp;
|
|
|
|
|
|
//
|
|
// calculate aligned transfer size (no change if !do_align)
|
|
//
|
|
|
|
off_t actual_ofs = data_ofs;
|
|
size_t actual_size = data_size;
|
|
void* actual_buf = data_buf;
|
|
|
|
// note: we go to the trouble of aligning the first block (instead of
|
|
// just reading up to the next block and letting aio realign it),
|
|
// so that it can be taken from the cache.
|
|
// this is not possible if !do_align, since we have to allocate
|
|
// extra buffer space for the padding.
|
|
|
|
const size_t ofs_misalign = data_ofs % BLOCK_SIZE;
|
|
const size_t lead_padding = do_align? ofs_misalign : 0;
|
|
// for convenience; used below.
|
|
actual_ofs -= (off_t)lead_padding;
|
|
actual_size = round_up(lead_padding + data_size, BLOCK_SIZE);
|
|
|
|
|
|
// skip aio code, use lowio
|
|
if(no_aio)
|
|
return lowio(f->fd, is_write, data_ofs, data_size, data_buf);
|
|
|
|
|
|
//
|
|
// now we read the file in 64 KiB chunks, N-buffered.
|
|
// if reading from Zip, inflate while reading the next block.
|
|
//
|
|
|
|
const int MAX_IOS = 4;
|
|
IOSlot ios[MAX_IOS] = { {0} };
|
|
|
|
|
|
int head = 0;
|
|
int tail = 0;
|
|
int pending_ios = 0;
|
|
|
|
bool all_issued = false;
|
|
|
|
// (useful, raw data: possibly compressed, but doesn't count padding)
|
|
size_t raw_transferred_cnt = 0;
|
|
size_t issue_cnt = 0;
|
|
|
|
// if callback, what it reports; otherwise, = raw_transferred_cnt
|
|
// this is what we'll return
|
|
size_t actual_transferred_cnt = 0;
|
|
|
|
ssize_t err = +1; // loop terminates if <= 0
|
|
|
|
for(;;)
|
|
{
|
|
// queue not full, data remaining to transfer, and no error:
|
|
// start transferring next block.
|
|
if(pending_ios < MAX_IOS && !all_issued && err > 0)
|
|
{
|
|
// get next free IO slot in ring buffer
|
|
IOSlot* slot = &ios[head];
|
|
memset(slot, 0, sizeof(IOSlot));
|
|
head = (head + 1) % MAX_IOS;
|
|
pending_ios++;
|
|
|
|
off_t issue_ofs = (off_t)(actual_ofs + issue_cnt);
|
|
|
|
void* buf = (temp)? 0 : (char*)actual_buf + issue_cnt;
|
|
ssize_t issued = block_issue(f, slot, issue_ofs, buf);
|
|
debug_printf("FILE| io2: block_issue: %d\n", issued);
|
|
if(issued < 0)
|
|
err = issued;
|
|
// transfer failed - loop will now terminate after
|
|
// waiting for all pending transfers to complete.
|
|
|
|
issue_cnt += issued;
|
|
if(issue_cnt >= actual_size)
|
|
all_issued = true;
|
|
|
|
}
|
|
// IO pending: wait for it to complete, and process it.
|
|
else if(pending_ios)
|
|
{
|
|
IOSlot* slot = &ios[tail];
|
|
tail = (tail + 1) % MAX_IOS;
|
|
pending_ios--;
|
|
|
|
void* block = slot->cached_block;
|
|
size_t size = BLOCK_SIZE;
|
|
// wasn't in cache; it was issued, so wait for it
|
|
bool from_cache;
|
|
if(block)
|
|
from_cache = true;
|
|
else
|
|
{
|
|
from_cache = false;
|
|
|
|
int ret = file_io_wait(&slot->io, block, size);
|
|
if(ret < 0)
|
|
err = (ssize_t)ret;
|
|
}
|
|
|
|
// first time; skip past padding
|
|
void* data = block;
|
|
if(raw_transferred_cnt == 0)
|
|
{
|
|
(char*&)data += lead_padding;
|
|
size -= lead_padding;
|
|
}
|
|
|
|
// don't include trailing padding
|
|
if(raw_transferred_cnt + size > data_size)
|
|
size = data_size - raw_transferred_cnt;
|
|
|
|
|
|
|
|
// we have useable data from a previous temp buffer,
|
|
// but it needs to be copied into the user's buffer
|
|
if(from_cache && !temp)
|
|
memcpy2((char*)data_buf+raw_transferred_cnt, data, size);
|
|
|
|
|
|
//// if size comes out short, we must be at EOF
|
|
|
|
raw_transferred_cnt += size;
|
|
|
|
if(cb && !(err <= 0))
|
|
{
|
|
ssize_t ret = cb(ctx, data, size);
|
|
// if negative: processing failed.
|
|
// loop will now terminate after waiting for all
|
|
// pending transfers to complete.
|
|
// note: don't abort if = 0: zip callback may not actually
|
|
// output anything if passed very little data.
|
|
if(ret < 0)
|
|
err = ret;
|
|
else
|
|
actual_transferred_cnt += ret;
|
|
}
|
|
// no callback to process data: raw = actual
|
|
else
|
|
actual_transferred_cnt += size;
|
|
|
|
if(!from_cache)
|
|
file_io_discard(&slot->io);
|
|
|
|
if(temp)
|
|
{
|
|
// adding is allowed and we didn't take this from the cache already: add
|
|
if(!slot->cached_block)
|
|
block_add(slot->block_id, slot->temp_buf);
|
|
}
|
|
|
|
}
|
|
// (all issued OR error) AND no pending transfers - done.
|
|
else
|
|
break;
|
|
}
|
|
|
|
debug_printf("FILE| err=%d, actual_transferred_cnt=%d\n", err, actual_transferred_cnt);
|
|
|
|
// failed (0 means callback reports it's finished)
|
|
if(err < 0)
|
|
return err;
|
|
|
|
debug_assert(issue_cnt >= raw_transferred_cnt && raw_transferred_cnt >= data_size);
|
|
|
|
return (ssize_t)actual_transferred_cnt;
|
|
}
|
|
|
|
|
|
///////////////////////////////////////////////////////////////////////////////
|
|
//
|
|
// memory mapping
|
|
//
|
|
///////////////////////////////////////////////////////////////////////////////
|
|
|
|
|
|
// no significance aside from preventing uint overflow.
|
|
static const uint MAX_MAP_REFS = 255;
|
|
|
|
|
|
// map the entire file <f> into memory. if already currently mapped,
|
|
// return the previous mapping (reference-counted).
|
|
// output parameters are zeroed on failure.
|
|
//
|
|
// the mapping will be removed (if still open) when its file is closed.
|
|
// however, map/unmap calls should still be paired so that the mapping
|
|
// may be removed when no longer needed.
|
|
//
|
|
// rationale: reference counting is required for zip_map: several
|
|
// Zip "mappings" each reference one ZArchive's actual file mapping.
|
|
// implement it here so that we also get refcounting for normal files.
|
|
int file_map(File* f, void*& p, size_t& size)
|
|
{
|
|
p = 0;
|
|
size = 0;
|
|
|
|
CHECK_FILE(f);
|
|
|
|
const int prot = (f->flags & FILE_WRITE)? PROT_WRITE : PROT_READ;
|
|
|
|
// already mapped - increase refcount and return previous mapping.
|
|
if(f->mapping)
|
|
{
|
|
// prevent overflow; if we have this many refs, should find out why.
|
|
if(f->map_refs >= MAX_MAP_REFS)
|
|
{
|
|
debug_warn("too many references to mapping");
|
|
return -1;
|
|
}
|
|
f->map_refs++;
|
|
goto have_mapping;
|
|
}
|
|
|
|
// don't allow mapping zero-length files (doesn't make sense,
|
|
// and BoundsChecker warns about wposix mmap failing).
|
|
// then again, don't complain, because this might happen when mounting
|
|
// a dir containing empty files; each is opened as a Zip file.
|
|
if(f->size == 0)
|
|
return -1;
|
|
|
|
f->mapping = mmap((void*)0, f->size, prot, MAP_PRIVATE, f->fd, (off_t)0);
|
|
if(!f->mapping)
|
|
return ERR_NO_MEM;
|
|
|
|
f->map_refs = 1;
|
|
|
|
have_mapping:
|
|
p = f->mapping;
|
|
size = f->size;
|
|
return 0;
|
|
}
|
|
|
|
|
|
// decrement the reference count for the mapping belonging to file <f>.
|
|
// fail if there are no references; remove the mapping if the count reaches 0.
|
|
//
|
|
// the mapping will be removed (if still open) when its file is closed.
|
|
// however, map/unmap calls should still be paired so that the mapping
|
|
// may be removed when no longer needed.
|
|
int file_unmap(File* f)
|
|
{
|
|
CHECK_FILE(f);
|
|
|
|
// file is not currently mapped
|
|
if(f->map_refs == 0)
|
|
{
|
|
debug_warn("not currently mapped");
|
|
return -1;
|
|
}
|
|
|
|
// still more than one reference remaining - done.
|
|
if(--f->map_refs > 0)
|
|
return 0;
|
|
|
|
// no more references: remove the mapping
|
|
void* p = f->mapping;
|
|
f->mapping = 0;
|
|
// don't clear f->size - the file is still open.
|
|
|
|
return munmap(p, f->size);
|
|
}
|
|
|
|
|
|
int file_shutdown()
|
|
{
|
|
aiocb_pool_shutdown();
|
|
block_shutdown();
|
|
return 0;
|
|
}
|