diff options
-rw-r--r-- | erts/configure.in | 37 | ||||
-rw-r--r-- | erts/emulator/drivers/common/efile_drv.c | 31 | ||||
-rw-r--r-- | erts/emulator/drivers/common/erl_efile.h | 1 | ||||
-rw-r--r-- | erts/emulator/drivers/common/ram_file_drv.c | 8 | ||||
-rw-r--r-- | erts/emulator/drivers/unix/unix_efile.c | 92 | ||||
-rw-r--r-- | erts/emulator/drivers/win32/win_efile.c | 10 | ||||
-rw-r--r-- | erts/preloaded/src/prim_file.erl | 8 | ||||
-rw-r--r-- | lib/kernel/doc/src/file.xml | 12 | ||||
-rw-r--r-- | lib/kernel/src/file.erl | 14 | ||||
-rw-r--r-- | lib/kernel/src/file_io_server.erl | 4 | ||||
-rw-r--r-- | lib/kernel/src/ram_file.erl | 7 | ||||
-rw-r--r-- | lib/kernel/test/file_SUITE.erl | 72 | ||||
-rw-r--r-- | lib/kernel/test/prim_file_SUITE.erl | 74 |
13 files changed, 363 insertions, 7 deletions
diff --git a/erts/configure.in b/erts/configure.in index 3256b0cb59..be9a753f7f 100644 --- a/erts/configure.in +++ b/erts/configure.in @@ -1075,8 +1075,43 @@ fi AC_SUBST(ERTS_BUILD_SMP_EMU) -AC_CHECK_FUNCS([posix_fadvise]) +AC_CHECK_FUNCS([posix_fadvise, fallocate]) +AC_CHECK_HEADERS([linux/falloc.h]) +dnl * Old glibcs have broken posix_fallocate(). Make sure not to use it. +dnl * It may also be broken in AIX. +AC_CACHE_CHECK([whether posix_fallocate() works],i_cv_posix_fallocate_works,[ + AC_TRY_RUN([ + #if !defined(__sun) && !defined(__sun__) + #define _XOPEN_SOURCE 600 + #endif + #include <stdio.h> + #include <stdlib.h> + #include <fcntl.h> + #include <unistd.h> + #if defined(__GLIBC__) && (__GLIBC__ < 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ < 7)) + possibly broken posix_fallocate + #endif + int main() { + int fd = creat("conftest.temp", 0600); + int ret; + if (-1 == fd) { + perror("creat()"); + return 2; + } + ret = posix_fallocate(fd, 1024, 1024) < 0 ? 1 : 0; + unlink("conftest.temp"); + return ret; + } + ], [ + i_cv_posix_fallocate_works=yes + ], [ + i_cv_posix_fallocate_works=no + ]) +]) +if test $i_cv_posix_fallocate_works = yes; then + AC_DEFINE(HAVE_POSIX_FALLOCATE,, Define if you have a working posix_fallocate()) +fi # # Figure out if the emulator should use threads. The default is set above diff --git a/erts/emulator/drivers/common/efile_drv.c b/erts/emulator/drivers/common/efile_drv.c index 912f5d3d8b..2c38e7256a 100644 --- a/erts/emulator/drivers/common/efile_drv.c +++ b/erts/emulator/drivers/common/efile_drv.c @@ -56,6 +56,7 @@ #define FILE_FDATASYNC 30 #define FILE_FADVISE 31 #define FILE_SENDFILE 32 +#define FILE_FALLOCATE 33 /* Return codes */ @@ -503,6 +504,10 @@ struct t_data Uint64 written; } sendfile; #endif /* HAVE_SENDFILE */ + struct { + Sint64 offset; + Sint64 length; + } fallocate; } c; char b[1]; }; @@ -1953,6 +1958,17 @@ static int flush_sendfile(file_descriptor *desc,void *_) { #endif /* HAVE_SENDFILE */ +static void invoke_fallocate(void *data) +{ + struct t_data *d = (struct t_data *) data; + int fd = (int) d->fd; + Sint64 offset = d->c.fallocate.offset; + Sint64 length = d->c.fallocate.length; + + d->again = 0; + d->result_ok = efile_fallocate(&d->errInfo, fd, offset, length); +} + static void free_readdir(void *data) { struct t_data *d = (struct t_data *) data; @@ -2348,6 +2364,7 @@ file_async_ready(ErlDrvData e, ErlDrvThreadData data) case FILE_RENAME: case FILE_WRITE_INFO: case FILE_FADVISE: + case FILE_FALLOCATE: reply(desc, d->result_ok, &d->errInfo); free_data(data); break; @@ -2958,6 +2975,20 @@ file_output(ErlDrvData e, char* buf, ErlDrvSizeT count) goto done; } + case FILE_FALLOCATE: + { + d = EF_SAFE_ALLOC(sizeof(struct t_data)); + + d->fd = fd; + d->command = command; + d->invoke = invoke_fallocate; + d->free = free_data; + d->level = 2; + d->c.fallocate.offset = get_int64((uchar*) buf); + d->c.fallocate.length = get_int64(((uchar*) buf) + sizeof(Sint64)); + goto done; + } + } /* diff --git a/erts/emulator/drivers/common/erl_efile.h b/erts/emulator/drivers/common/erl_efile.h index 69ad02633c..b29b4f971c 100644 --- a/erts/emulator/drivers/common/erl_efile.h +++ b/erts/emulator/drivers/common/erl_efile.h @@ -185,3 +185,4 @@ int efile_fadvise(Efile_error* errInfo, int fd, Sint64 offset, Sint64 length, int efile_sendfile(Efile_error* errInfo, int in_fd, int out_fd, off_t *offset, Uint64 *nbytes, struct t_sendfile_hdtl *hdtl); #endif /* HAVE_SENDFILE */ +int efile_fallocate(Efile_error* errInfo, int fd, Sint64 offset, Sint64 length); diff --git a/erts/emulator/drivers/common/ram_file_drv.c b/erts/emulator/drivers/common/ram_file_drv.c index a109e40333..7f7cd7cd91 100644 --- a/erts/emulator/drivers/common/ram_file_drv.c +++ b/erts/emulator/drivers/common/ram_file_drv.c @@ -48,6 +48,7 @@ #define RAM_FILE_SIZE 37 /* get file size */ #define RAM_FILE_ADVISE 38 /* predeclare the access * pattern for file data */ +#define RAM_FILE_ALLOCATE 39 /* allocate space for a file */ /* possible new operations include: DES_ENCRYPT DES_DECRYPT @@ -720,6 +721,13 @@ static void rfile_command(ErlDrvData e, char* buf, ErlDrvSizeT count) else reply(f, 1, 0); break; + + case RAM_FILE_ALLOCATE: + if (f->flags == 0) + error_reply(f, EBADF); + else + reply(f, 1, 0); + break; } /* * Ignore anything else -- let the caller hang. diff --git a/erts/emulator/drivers/unix/unix_efile.c b/erts/emulator/drivers/unix/unix_efile.c index cf7af71b92..558651fff9 100644 --- a/erts/emulator/drivers/unix/unix_efile.c +++ b/erts/emulator/drivers/unix/unix_efile.c @@ -22,6 +22,12 @@ #ifdef HAVE_CONFIG_H # include "config.h" #endif +#if defined(HAVE_POSIX_FALLOCATE) && !defined(__sun) && !defined(__sun__) +#define _XOPEN_SOURCE 600 +#endif +#if !defined(_GNU_SOURCE) && defined(HAVE_LINUX_FALLOC_H) +#define _GNU_SOURCE +#endif #include "sys.h" #include "erl_driver.h" #include "erl_efile.h" @@ -41,9 +47,13 @@ #define DARWIN 1 #endif -#ifdef DARWIN +#if defined(DARWIN) || defined(HAVE_LINUX_FALLOC_H) || defined(HAVE_POSIX_FALLOCATE) #include <fcntl.h> -#endif /* DARWIN */ +#endif + +#ifdef HAVE_LINUX_FALLOC_H +#include <linux/falloc.h> +#endif #ifdef SUNOS4 # define getcwd(buf, size) getwd(buf) @@ -967,3 +977,81 @@ efile_sendfile(Efile_error* errInfo, int in_fd, int out_fd, return check_error(retval, errInfo); } #endif /* HAVE_SENDFILE */ + +#ifdef HAVE_POSIX_FALLOCATE +static int +call_posix_fallocate(int fd, Sint64 offset, Sint64 length) +{ + int ret; + + /* + * On Linux and Solaris for example, posix_fallocate() returns + * a positive error number on error and it does not set errno. + * On FreeBSD however (9.0 at least), it returns -1 on error + * and it sets errno. + */ + do { + ret = posix_fallocate(fd, (off_t) offset, (off_t) length); + if (ret > 0) { + errno = ret; + ret = -1; + } + } while (ret != 0 && errno == EINTR); + + return ret; +} +#endif /* HAVE_POSIX_FALLOCATE */ + +int +efile_fallocate(Efile_error* errInfo, int fd, Sint64 offset, Sint64 length) +{ +#if defined HAVE_FALLOCATE + /* Linux specific, more efficient than posix_fallocate. */ + int ret; + + do { + ret = fallocate(fd, FALLOC_FL_KEEP_SIZE, (off_t) offset, (off_t) length); + } while (ret != 0 && errno == EINTR); + +#if defined HAVE_POSIX_FALLOCATE + /* Fallback to posix_fallocate if available. */ + if (ret != 0) { + ret = call_posix_fallocate(fd, offset, length); + } +#endif + + return check_error(ret, errInfo); +#elif defined F_PREALLOCATE + /* Mac OS X specific, equivalent to posix_fallocate. */ + int ret; + fstore_t fs; + + memset(&fs, 0, sizeof(fs)); + fs.fst_flags = F_ALLOCATECONTIG; + fs.fst_posmode = F_VOLPOSMODE; + fs.fst_offset = (off_t) offset; + fs.fst_length = (off_t) length; + + ret = fcntl(fd, F_PREALLOCATE, &fs); + + if (-1 == ret) { + fs.fst_flags = F_ALLOCATEALL; + ret = fcntl(fd, F_PREALLOCATE, &fs); + +#if defined HAVE_POSIX_FALLOCATE + /* Fallback to posix_fallocate if available. */ + if (-1 == ret) { + ret = call_posix_fallocate(fd, offset, length); + } +#endif + } + + return check_error(ret, errInfo); +#elif defined HAVE_POSIX_FALLOCATE + /* Other Unixes, use posix_fallocate if available. */ + return check_error(call_posix_fallocate(fd, offset, length), errInfo); +#else + errno = ENOTSUP; + return check_error(-1, errInfo); +#endif +} diff --git a/erts/emulator/drivers/win32/win_efile.c b/erts/emulator/drivers/win32/win_efile.c index dc7add01f7..f5011d11a5 100644 --- a/erts/emulator/drivers/win32/win_efile.c +++ b/erts/emulator/drivers/win32/win_efile.c @@ -1558,3 +1558,13 @@ efile_fadvise(Efile_error* errInfo, int fd, Sint64 offset, errno = ERROR_SUCCESS; return check_error(0, errInfo); } + +int +efile_fallocate(Efile_error* errInfo, int fd, Sint64 offset, Sint64 length) +{ + /* No file preallocation method available in Windows. */ + errno = errno_map(ERROR_NOT_SUPPORTED); + SetLastError(ERROR_NOT_SUPPORTED); + + return check_error(-1, errInfo); +} diff --git a/erts/preloaded/src/prim_file.erl b/erts/preloaded/src/prim_file.erl index eafab1bae4..c412b7faf2 100644 --- a/erts/preloaded/src/prim_file.erl +++ b/erts/preloaded/src/prim_file.erl @@ -27,7 +27,7 @@ %% Generic file contents operations -export([open/2, close/1, datasync/1, sync/1, advise/4, position/2, truncate/1, write/2, pwrite/2, pwrite/3, read/2, read_line/1, pread/2, pread/3, - copy/3, sendfile/10]). + copy/3, sendfile/10, allocate/3]). %% Specialized file operations -export([open/1, open/3]). @@ -100,6 +100,7 @@ -define(FILE_FDATASYNC, 30). -define(FILE_ADVISE, 31). -define(FILE_SENDFILE, 32). +-define(FILE_ALLOCATE, 33). %% Driver responses -define(FILE_RESP_OK, 0). @@ -293,6 +294,11 @@ advise(#file_descriptor{module = ?MODULE, data = {Port, _}}, end. %% Returns {error, Reason} | ok. +allocate(#file_descriptor{module = ?MODULE, data = {Port, _}}, Offset, Length) -> + Cmd = <<?FILE_ALLOCATE, Offset:64/signed, Length:64/signed>>, + drv_command(Port, Cmd). + +%% Returns {error, Reason} | ok. write(#file_descriptor{module = ?MODULE, data = {Port, _}}, Bytes) -> case drv_command_nt(Port, [?FILE_WRITE,erlang:dt_prepend_vm_tag_data(Bytes)],undefined) of {ok, _Size} -> diff --git a/lib/kernel/doc/src/file.xml b/lib/kernel/doc/src/file.xml index 536b98b5f5..e30ade1bd2 100644 --- a/lib/kernel/doc/src/file.xml +++ b/lib/kernel/doc/src/file.xml @@ -170,6 +170,18 @@ </desc> </func> <func> + <name name="allocate" arity="3"/> + <fsummary>Allocate file space</fsummary> + <desc> + <p><c>allocate/3</c> can be used to preallocate space for a file.</p> + <p>This function only succeeds in platforms that implement this + feature. When it succeeds, space is preallocated for the file but + the file size might not be updated. This behaviour depends on the + preallocation implementation. To guarantee the file size is updated + one must truncate the file to the new size.</p> + </desc> + </func> + <func> <name name="change_group" arity="2"/> <fsummary>Change group of a file</fsummary> <desc> diff --git a/lib/kernel/src/file.erl b/lib/kernel/src/file.erl index de3eaad5a1..16f2dde464 100644 --- a/lib/kernel/src/file.erl +++ b/lib/kernel/src/file.erl @@ -38,7 +38,7 @@ %% Specialized -export([ipread_s32bu_p32bu/3]). %% Generic file contents. --export([open/2, close/1, advise/4, +-export([open/2, close/1, advise/4, allocate/3, read/2, write/2, pread/2, pread/3, pwrite/2, pwrite/3, read_line/1, @@ -490,6 +490,18 @@ advise(#file_descriptor{module = Module} = Handle, Offset, Length, Advise) -> advise(_, _, _, _) -> {error, badarg}. +-spec allocate(File, Offset, Length) -> + 'ok' | {'error', posix()} when + File :: io_device(), + Offset :: non_neg_integer(), + Length :: non_neg_integer(). + +allocate(File, Offset, Length) when is_pid(File) -> + R = file_request(File, {allocate, Offset, Length}), + wait_file_reply(File, R); +allocate(#file_descriptor{module = Module} = Handle, Offset, Length) -> + Module:allocate(Handle, Offset, Length). + -spec read(IoDevice, Number) -> {ok, Data} | eof | {error, Reason} when IoDevice :: io_device() | atom(), Number :: non_neg_integer(), diff --git a/lib/kernel/src/file_io_server.erl b/lib/kernel/src/file_io_server.erl index acaffe1e41..fad2ed7fb3 100644 --- a/lib/kernel/src/file_io_server.erl +++ b/lib/kernel/src/file_io_server.erl @@ -211,6 +211,10 @@ file_request({advise,Offset,Length,Advise}, Reply -> {reply,Reply,State} end; +file_request({allocate, Offset, Length}, + #state{handle = Handle} = State) -> + Reply = ?PRIM_FILE:allocate(Handle, Offset, Length), + {reply, Reply, State}; file_request({pread,At,Sz}, #state{handle=Handle,buf=Buf,read_mode=ReadMode}=State) -> case position(Handle, At, Buf) of diff --git a/lib/kernel/src/ram_file.erl b/lib/kernel/src/ram_file.erl index 48ea871433..ca881ff8a4 100644 --- a/lib/kernel/src/ram_file.erl +++ b/lib/kernel/src/ram_file.erl @@ -29,6 +29,7 @@ %% Specialized file operations -export([get_size/1, get_file/1, set_file/2, get_file_close/1]). -export([compress/1, uncompress/1, uuencode/1, uudecode/1, advise/4]). +-export([allocate/3]). -export([open_mode/1]). %% used by ftp-file @@ -72,6 +73,7 @@ -define(RAM_FILE_UUDECODE, 36). -define(RAM_FILE_SIZE, 37). -define(RAM_FILE_ADVISE, 38). +-define(RAM_FILE_ALLOCATE, 39). %% Open modes for RAM_FILE_OPEN -define(RAM_FILE_MODE_READ, 1). @@ -383,6 +385,11 @@ advise(#file_descriptor{module = ?MODULE, data = Port}, Offset, advise(#file_descriptor{}, _Offset, _Length, _Advise) -> {error, enotsup}. +allocate(#file_descriptor{module = ?MODULE, data = Port}, Offset, Length) -> + call_port(Port, <<?RAM_FILE_ALLOCATE, Offset:64/signed, Length:64/signed>>); +allocate(#file_descriptor{}, _Offset, _Length) -> + {error, enotsup}. + %%%----------------------------------------------------------------- diff --git a/lib/kernel/test/file_SUITE.erl b/lib/kernel/test/file_SUITE.erl index 9c507fd437..914f0d6127 100644 --- a/lib/kernel/test/file_SUITE.erl +++ b/lib/kernel/test/file_SUITE.erl @@ -84,6 +84,8 @@ -export([advise/1]). +-export([allocate/1]). + -export([standard_io/1,mini_server/1]). %% Debug exports @@ -116,7 +118,7 @@ groups() -> {files, [], [{group, open}, {group, pos}, {group, file_info}, {group, consult}, {group, eval}, {group, script}, - truncate, sync, datasync, advise]}, + truncate, sync, datasync, advise, allocate]}, {open, [], [open1, old_modes, new_modes, path_open, close, access, read_write, pread_write, append, open_errors, @@ -1617,6 +1619,74 @@ advise(Config) when is_list(Config) -> ?line test_server:timetrap_cancel(Dog), ok. +allocate(suite) -> []; +allocate(doc) -> "Tests that ?FILE_MODULE:allocate/3 at least doesn't crash."; +allocate(Config) when is_list(Config) -> + ?line Dog = test_server:timetrap(test_server:seconds(5)), + ?line PrivDir = ?config(priv_dir, Config), + ?line Allocate = filename:join(PrivDir, + atom_to_list(?MODULE) + ++"_allocate.fil"), + + Line1 = "Hello\n", + Line2 = "World!\n", + + ?line {ok, Fd} = ?FILE_MODULE:open(Allocate, [write, binary]), + allocate_and_assert(Fd, 1, iolist_size([Line1, Line2])), + ?line ok = io:format(Fd, "~s", [Line1]), + ?line ok = io:format(Fd, "~s", [Line2]), + ?line ok = ?FILE_MODULE:close(Fd), + + ?line {ok, Fd2} = ?FILE_MODULE:open(Allocate, [write, binary]), + allocate_and_assert(Fd2, 1, iolist_size(Line1)), + ?line ok = io:format(Fd2, "~s", [Line1]), + ?line ok = io:format(Fd2, "~s", [Line2]), + ?line ok = ?FILE_MODULE:close(Fd2), + + ?line {ok, Fd3} = ?FILE_MODULE:open(Allocate, [write, binary]), + allocate_and_assert(Fd3, 1, iolist_size(Line1) + 1), + ?line ok = io:format(Fd3, "~s", [Line1]), + ?line ok = io:format(Fd3, "~s", [Line2]), + ?line ok = ?FILE_MODULE:close(Fd3), + + ?line {ok, Fd4} = ?FILE_MODULE:open(Allocate, [write, binary]), + allocate_and_assert(Fd4, 1, 4 * iolist_size([Line1, Line2])), + ?line ok = io:format(Fd4, "~s", [Line1]), + ?line ok = io:format(Fd4, "~s", [Line2]), + ?line ok = ?FILE_MODULE:close(Fd4), + + ?line [] = flush(), + ?line test_server:timetrap_cancel(Dog), + ok. + +allocate_and_assert(Fd, Offset, Length) -> + % Just verify that calls to ?PRIM_FILE:allocate/3 don't crash or have + % any other negative side effect. We can't really asssert against a + % specific return value, because support for file space pre-allocation + % depends on the OS, OS version and underlying filesystem. + % + % The Linux kernel added support for fallocate() in version 2.6.23, + % which currently works only for the ext4, ocfs2, xfs and btrfs file + % systems. posix_fallocate() is available in glibc as of version + % 2.1.94, but it was buggy until glibc version 2.7. + % + % Mac OS X, as of version 10.3, supports the fcntl operation F_PREALLOCATE. + % + % Solaris supports posix_fallocate() but only for the UFS file system + % apparently (not supported for ZFS). + % + % FreeBSD 9.0 is the first FreeBSD release supporting posix_fallocate(). + % + % For Windows there's apparently no way to pre-allocate file space, at + % least with same semantics as posix_fallocate(), fallocate() and + % fcntl F_PREALLOCATE. + Result = ?FILE_MODULE:allocate(Fd, Offset, Length), + case os:type() of + {win32, _} -> + ?line {error, enotsup} = Result; + _ -> + ?line _ = Result + end. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% diff --git a/lib/kernel/test/prim_file_SUITE.erl b/lib/kernel/test/prim_file_SUITE.erl index a56746bbc4..4e93a593b3 100644 --- a/lib/kernel/test/prim_file_SUITE.erl +++ b/lib/kernel/test/prim_file_SUITE.erl @@ -57,6 +57,8 @@ %% System probe functions that might be handy to check from the shell -export([unix_free/1]). +-export([allocate/1]). + -include_lib("test_server/include/test_server.hrl"). -include_lib("kernel/include/file.hrl"). @@ -87,7 +89,7 @@ groups() -> cur_dir_1a, cur_dir_1b]}, {files, [], [{group, open}, {group, pos}, {group, file_info}, - truncate, sync, datasync, advise, large_write]}, + truncate, sync, datasync, advise, large_write, allocate]}, {open, [], [open1, modes, close, access, read_write, pread_write, append, exclusive]}, @@ -1359,6 +1361,76 @@ check_large_write(Dog, Fd, _, _, []) -> %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +allocate(suite) -> []; +allocate(doc) -> "Tests that ?PRIM_FILE:allocate/3 at least doesn't crash."; +allocate(Config) when is_list(Config) -> + ?line Dog = test_server:timetrap(test_server:seconds(5)), + ?line PrivDir = ?config(priv_dir, Config), + ?line Allocate = filename:join(PrivDir, + atom_to_list(?MODULE) + ++"_allocate.fil"), + + Line1 = "Hello\n", + Line2 = "World!\n", + + ?line {ok, Fd} = ?PRIM_FILE:open(Allocate, [write, binary]), + allocate_and_assert(Fd, 1, iolist_size([Line1, Line2])), + ?line ok = ?PRIM_FILE:write(Fd, Line1), + ?line ok = ?PRIM_FILE:write(Fd, Line2), + ?line ok = ?PRIM_FILE:close(Fd), + + ?line {ok, Fd2} = ?PRIM_FILE:open(Allocate, [write, binary]), + allocate_and_assert(Fd2, 1, iolist_size(Line1)), + ?line ok = ?PRIM_FILE:write(Fd2, Line1), + ?line ok = ?PRIM_FILE:write(Fd2, Line2), + ?line ok = ?PRIM_FILE:close(Fd2), + + ?line {ok, Fd3} = ?PRIM_FILE:open(Allocate, [write, binary]), + allocate_and_assert(Fd3, 1, iolist_size(Line1) + 1), + ?line ok = ?PRIM_FILE:write(Fd3, Line1), + ?line ok = ?PRIM_FILE:write(Fd3, Line2), + ?line ok = ?PRIM_FILE:close(Fd3), + + ?line {ok, Fd4} = ?PRIM_FILE:open(Allocate, [write, binary]), + allocate_and_assert(Fd4, 1, 4 * iolist_size([Line1, Line2])), + ?line ok = ?PRIM_FILE:write(Fd4, Line1), + ?line ok = ?PRIM_FILE:write(Fd4, Line2), + ?line ok = ?PRIM_FILE:close(Fd4), + + ?line test_server:timetrap_cancel(Dog), + ok. + +allocate_and_assert(Fd, Offset, Length) -> + % Just verify that calls to ?PRIM_FILE:allocate/3 don't crash or have + % any other negative side effect. We can't really asssert against a + % specific return value, because support for file space pre-allocation + % depends on the OS, OS version and underlying filesystem. + % + % The Linux kernel added support for fallocate() in version 2.6.23, + % which currently works only for the ext4, ocfs2, xfs and btrfs file + % systems. posix_fallocate() is available in glibc as of version + % 2.1.94, but it was buggy until glibc version 2.7. + % + % Mac OS X, as of version 10.3, supports the fcntl operation F_PREALLOCATE. + % + % Solaris supports posix_fallocate() but only for the UFS file system + % apparently (not supported for ZFS). + % + % FreeBSD 9.0 is the first FreeBSD release supporting posix_fallocate(). + % + % For Windows there's apparently no way to pre-allocate file space, at + % least with similar API/semantics as posix_fallocate(), fallocate() or + % fcntl F_PREALLOCATE. + Result = ?PRIM_FILE:allocate(Fd, Offset, Length), + case os:type() of + {win32, _} -> + ?line {error, enotsup} = Result; + _ -> + ?line _ = Result + end. + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + delete_a(suite) -> []; delete_a(doc) -> []; delete_a(Config) when is_list(Config) -> |