Merge branch 'fm/file-operations' into dev

* fm/file-operations:
  Update preloaded modules
  Add file:advise/4 - a wrapper to the POSIX syscall posix_fadvise
  Add file:datasync/1 for syncing file contents only
  sys.h: Correct the get_int64() macro

OTP-8637 fm/file-operations

The functions file:advise/4 and file:datasync/1 have been added. (Thanks to
Filipe David Manana.)

16 files changed, 188 insertions, 24 deletions

diff --git a/erts/configure.in b/erts/configure.in
index a14b10adbf..63bf548c89 100644
--- a/erts/configure.in
+++ b/erts/configure.in
@@ -1054,6 +1054,7 @@ fi
 
 AC_SUBST(ERTS_BUILD_SMP_EMU)
 
+AC_CHECK_FUNCS([posix_fadvise])
 
 
 #
@@ -1757,6 +1758,12 @@ fi
 dnl Need by run_erl.
 AC_CHECK_FUNCS([openpty])
 
+dnl fdatasync syscall (Unix only)
+AC_CHECK_FUNCS([fdatasync])
+
+dnl Find which C libraries are required to use fdatasync
+AC_SEARCH_LIBS(fdatasync, [rt])
+
 dnl ----------------------------------------------------------------------
 dnl Checks for features/quirks in the system that affects Erlang.
 dnl ----------------------------------------------------------------------
diff --git a/erts/emulator/beam/sys.h b/erts/emulator/beam/sys.h
index a1955235b7..0f20d36167 100644
--- a/erts/emulator/beam/sys.h
+++ b/erts/emulator/beam/sys.h
@@ -1173,14 +1173,14 @@ EXTERN_FUNCTION(void*, sys_calloc2, (Uint, Uint));
 
 /* Standard set of integer macros  .. */
 
-#define get_int64(s) ((((unsigned char*) (s))[0] << 56) | \
-                      (((unsigned char*) (s))[1] << 48) | \
-                      (((unsigned char*) (s))[2] << 40) | \
-                      (((unsigned char*) (s))[3] << 32) | \
-                      (((unsigned char*) (s))[4] << 24) | \
-                      (((unsigned char*) (s))[5] << 16) | \
-                      (((unsigned char*) (s))[6] << 8)  | \
-                      (((unsigned char*) (s))[7]))
+#define get_int64(s) (((Uint64)(((unsigned char*) (s))[0]) << 56) | \
+                      (((Uint64)((unsigned char*) (s))[1]) << 48) | \
+                      (((Uint64)((unsigned char*) (s))[2]) << 40) | \
+                      (((Uint64)((unsigned char*) (s))[3]) << 32) | \
+                      (((Uint64)((unsigned char*) (s))[4]) << 24) | \
+                      (((Uint64)((unsigned char*) (s))[5]) << 16) | \
+                      (((Uint64)((unsigned char*) (s))[6]) << 8)  | \
+                      (((Uint64)((unsigned char*) (s))[7])))
 
 #define put_int64(i, s) do {((char*)(s))[0] = (char)((Sint64)(i) >> 56) & 0xff;\
                             ((char*)(s))[1] = (char)((Sint64)(i) >> 48) & 0xff;\
diff --git a/erts/emulator/drivers/common/efile_drv.c b/erts/emulator/drivers/common/efile_drv.c
index d2b916000e..60ae4cb108 100644
--- a/erts/emulator/drivers/common/efile_drv.c
+++ b/erts/emulator/drivers/common/efile_drv.c
@@ -53,6 +53,8 @@
 #define FILE_IPREAD             27
 #define FILE_ALTNAME            28
 #define FILE_READ_LINE          29
+#define FILE_FDATASYNC          30
+#define FILE_FADVISE            31
 
 /* Return codes */
 
@@ -357,6 +359,11 @@ struct t_data
 	    struct t_readdir_buf *first_buf;
 	    struct t_readdir_buf *last_buf;
 	} read_dir;
+	struct {
+	    Sint64 offset;
+	    Sint64 length;
+	    int advise;
+	} fadvise;
     } c;
     char b[1];
 };
@@ -883,6 +890,15 @@ static void invoke_chdir(void *data)
     invoke_name(data, efile_chdir);
 }
 
+static void invoke_fdatasync(void *data)
+{
+    struct t_data *d = (struct t_data *) data;
+    int fd = (int) d->fd;
+
+    d->again = 0;
+    d->result_ok = efile_fdatasync(&d->errInfo, fd);
+}
+
 static void invoke_fsync(void *data)
 {
     struct t_data *d = (struct t_data *) data;
@@ -1637,6 +1653,18 @@ static void invoke_open(void *data)
     d->result_ok = status;
 }
 
+static void invoke_fadvise(void *data)
+{
+    struct t_data *d = (struct t_data *) data;
+    int fd = (int) d->fd;
+    off_t offset = (off_t) d->c.fadvise.offset;
+    off_t length = (off_t) d->c.fadvise.length;
+    int advise = (int) d->c.fadvise.advise;
+
+    d->again = 0;
+    d->result_ok = efile_fadvise(&d->errInfo, fd, offset, length, advise);
+}
+
 static void free_readdir(void *data)
 {
     struct t_data *d = (struct t_data *) data;
@@ -1919,12 +1947,14 @@ file_async_ready(ErlDrvData e, ErlDrvThreadData data)
       case FILE_RMDIR:
       case FILE_CHDIR:
       case FILE_DELETE:
+      case FILE_FDATASYNC:
       case FILE_FSYNC:
       case FILE_TRUNCATE:
       case FILE_LINK:
       case FILE_SYMLINK:
       case FILE_RENAME:
       case FILE_WRITE_INFO:
+      case FILE_FADVISE:
 	reply(desc, d->result_ok, &d->errInfo);
 	free_data(data);
 	break;
@@ -2209,6 +2239,18 @@ file_output(ErlDrvData e, char* buf, int count)
 	    goto done;
 	}
 
+    case FILE_FDATASYNC:
+    {
+	    d = EF_SAFE_ALLOC(sizeof(struct t_data));
+
+	    d->fd = fd;
+	    d->command = command;
+	    d->invoke = invoke_fdatasync;
+	    d->free = free_data;
+	    d->level = 2;
+	    goto done;
+    }
+
     case FILE_FSYNC:
     {
 	d = EF_SAFE_ALLOC(sizeof(struct t_data));
@@ -2332,6 +2374,21 @@ file_output(ErlDrvData e, char* buf, int count)
 	    goto done;
 	}
 
+    case FILE_FADVISE:
+    {
+        d = EF_SAFE_ALLOC(sizeof(struct t_data));
+
+        d->fd = fd;
+        d->command = command;
+        d->invoke = invoke_fadvise;
+        d->free = free_data;
+        d->level = 2;
+        d->c.fadvise.offset = get_int64((uchar*) buf);
+        d->c.fadvise.length = get_int64(((uchar*) buf) + sizeof(Sint64));
+        d->c.fadvise.advise = get_int32(((uchar*) buf) + 2 * sizeof(Sint64));
+        goto done;
+    }
+
     }
 
     /*
diff --git a/erts/emulator/drivers/common/erl_efile.h b/erts/emulator/drivers/common/erl_efile.h
index 9aa941e550..bbc973d58b 100644
--- a/erts/emulator/drivers/common/erl_efile.h
+++ b/erts/emulator/drivers/common/erl_efile.h
@@ -1,19 +1,19 @@
 /*
  * %CopyrightBegin%
- * 
- * Copyright Ericsson AB 1997-2009. All Rights Reserved.
- * 
+ *
+ * Copyright Ericsson AB 1997-2010. All Rights Reserved.
+ *
  * The contents of this file are subject to the Erlang Public License,
  * Version 1.1, (the "License"); you may not use this file except in
  * compliance with the License. You should have received a copy of the
  * Erlang Public License along with this software. If not, it can be
  * retrieved online at http://www.erlang.org/.
- * 
+ *
  * Software distributed under the License is distributed on an "AS IS"
  * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
  * the License for the specific language governing rights and limitations
  * under the License.
- * 
+ *
  * %CopyrightEnd%
  */
 /*
@@ -126,6 +126,7 @@ int efile_readdir(Efile_error* errInfo, char* name,
 int efile_openfile(Efile_error* errInfo, char* name, int flags,
 		   int* pfd, Sint64* pSize);
 void efile_closefile(int fd);
+int efile_fdatasync(Efile_error* errInfo, int fd);
 int efile_fsync(Efile_error* errInfo, int fd);
 int efile_fileinfo(Efile_error* errInfo, Efile_info* pInfo,
 		   char *name, int info_for_link);
@@ -150,3 +151,5 @@ int efile_altname(Efile_error* errInfo, char *name,
 int efile_link(Efile_error* errInfo, char* old, char* new);
 int efile_symlink(Efile_error* errInfo, char* old, char* new);
 int efile_may_openfile(Efile_error* errInfo, char *name);
+int efile_fadvise(Efile_error* errInfo, int fd, Sint64 offset, Sint64 length,
+		  int advise);
diff --git a/erts/emulator/drivers/common/ram_file_drv.c b/erts/emulator/drivers/common/ram_file_drv.c
index 4a39a156e6..abedcc933a 100644
--- a/erts/emulator/drivers/common/ram_file_drv.c
+++ b/erts/emulator/drivers/common/ram_file_drv.c
@@ -35,6 +35,7 @@
 #define RAM_FILE_TRUNCATE      14
 #define RAM_FILE_PREAD         17
 #define RAM_FILE_PWRITE        18
+#define RAM_FILE_FDATASYNC     19
 
 /* other operations */
 #define RAM_FILE_GET           30
@@ -45,6 +46,8 @@
 #define RAM_FILE_UUENCODE      35  /* uuencode file */
 #define RAM_FILE_UUDECODE      36  /* uudecode file */
 #define RAM_FILE_SIZE          37  /* get file size */
+#define RAM_FILE_ADVISE        38  /* predeclare the access
+                                    * pattern for file data */
 /* possible new operations include:
    DES_ENCRYPT
    DES_DECRYPT
@@ -558,6 +561,13 @@ static void rfile_command(ErlDrvData e, char* buf, int count)
 	    numeric_reply(f, 0); /* 0 is not used */
 	break;
 
+    case RAM_FILE_FDATASYNC:
+	if (f->flags == 0)
+	    error_reply(f, EBADF);
+	else
+	    reply(f, 1, 0);
+	break;
+
     case RAM_FILE_FSYNC:
 	if (f->flags == 0)
 	    error_reply(f, EBADF);
@@ -685,6 +695,13 @@ static void rfile_command(ErlDrvData e, char* buf, int count)
     case RAM_FILE_UUDECODE:   /* uudecode file */
 	ram_file_uudecode(f);
 	break;
+
+    case RAM_FILE_ADVISE:
+	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 1d094ee613..ea016526ef 100644
--- a/erts/emulator/drivers/unix/unix_efile.c
+++ b/erts/emulator/drivers/unix/unix_efile.c
@@ -774,6 +774,17 @@ efile_closefile(int fd)
 }
 
 int
+efile_fdatasync(Efile_error *errInfo, /* Where to return error codes. */
+	    int fd)               /* File descriptor for file to sync data. */
+{
+#ifdef HAVE_FDATASYNC
+    return check_error(fdatasync(fd), errInfo);
+#else
+    return efile_fsync(errInfo, fd);
+#endif
+}
+
+int
 efile_fsync(Efile_error *errInfo, /* Where to return error codes. */
 	    int fd)               /* File descriptor for file to sync. */
 {
@@ -1437,3 +1448,14 @@ efile_symlink(Efile_error* errInfo, char* old, char* new)
     return check_error(symlink(old, new), errInfo);
 #endif
 }
+
+int
+efile_fadvise(Efile_error* errInfo, int fd, Sint64 offset,
+		  Sint64 length, int advise)
+{
+#ifdef HAVE_POSIX_FADVISE
+    return check_error(posix_fadvise(fd, offset, length, advise), errInfo);
+#else
+    return check_error(0, errInfo);
+#endif
+}
diff --git a/erts/emulator/drivers/win32/win_efile.c b/erts/emulator/drivers/win32/win_efile.c
index 89aaad31da..d5f2b79706 100644
--- a/erts/emulator/drivers/win32/win_efile.c
+++ b/erts/emulator/drivers/win32/win_efile.c
@@ -1,19 +1,19 @@
 /*
  * %CopyrightBegin%
- * 
- * Copyright Ericsson AB 1997-2009. All Rights Reserved.
- * 
+ *
+ * Copyright Ericsson AB 1997-2010. All Rights Reserved.
+ *
  * The contents of this file are subject to the Erlang Public License,
  * Version 1.1, (the "License"); you may not use this file except in
  * compliance with the License. You should have received a copy of the
  * Erlang Public License along with this software. If not, it can be
  * retrieved online at http://www.erlang.org/.
- * 
+ *
  * Software distributed under the License is distributed on an "AS IS"
  * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
  * the License for the specific language governing rights and limitations
  * under the License.
- * 
+ *
  * %CopyrightEnd%
  */
 /*
@@ -764,6 +764,15 @@ int fd;				/* File descriptor for file to close. */
 }
 
 int
+efile_fdatasync(errInfo, fd)
+Efile_error* errInfo;		/* Where to return error codes. */
+int fd;				/* File descriptor for file to sync. */
+{
+    /* Not available in Windows, just call regular fsync */
+    return efile_fsync(errInfo, fd);
+}
+
+int
 efile_fsync(errInfo, fd)
 Efile_error* errInfo;		/* Where to return error codes. */
 int fd;				/* File descriptor for file to sync. */
@@ -1424,3 +1433,12 @@ efile_symlink(Efile_error* errInfo, char* old, char* new)
     errno = ENOTSUP;
     return check_error(-1, errInfo);
 }
+
+int
+efile_fadvise(Efile_error* errInfo, int fd, Sint64 offset,
+	    Sint64 length, int advise)
+{
+    /* posix_fadvise is not available on Windows, do nothing */
+    errno = ERROR_SUCCESS;
+    return check_error(0, errInfo);
+}
diff --git a/erts/preloaded/ebin/erl_prim_loader.beam b/erts/preloaded/ebin/erl_prim_loader.beam
index afd8a90b3f..fe3cee1c56 100644
--- a/erts/preloaded/ebin/erl_prim_loader.beam
+++ b/erts/preloaded/ebin/erl_prim_loader.beam
diff --git a/erts/preloaded/ebin/erlang.beam b/erts/preloaded/ebin/erlang.beam
index 4ec84948d8..5a4c5e9d1e 100644
--- a/erts/preloaded/ebin/erlang.beam
+++ b/erts/preloaded/ebin/erlang.beam
diff --git a/erts/preloaded/ebin/init.beam b/erts/preloaded/ebin/init.beam
index c3e746f3ee..cfe2c36cee 100644
--- a/erts/preloaded/ebin/init.beam
+++ b/erts/preloaded/ebin/init.beam
diff --git a/erts/preloaded/ebin/otp_ring0.beam b/erts/preloaded/ebin/otp_ring0.beam
index 4b2d8bb2de..74587de26b 100644
--- a/erts/preloaded/ebin/otp_ring0.beam
+++ b/erts/preloaded/ebin/otp_ring0.beam
diff --git a/erts/preloaded/ebin/prim_file.beam b/erts/preloaded/ebin/prim_file.beam
index 2916baaa77..c6610b71e6 100644
--- a/erts/preloaded/ebin/prim_file.beam
+++ b/erts/preloaded/ebin/prim_file.beam
diff --git a/erts/preloaded/ebin/prim_inet.beam b/erts/preloaded/ebin/prim_inet.beam
index 46912e2bea..8d19923281 100644
--- a/erts/preloaded/ebin/prim_inet.beam
+++ b/erts/preloaded/ebin/prim_inet.beam
diff --git a/erts/preloaded/ebin/prim_zip.beam b/erts/preloaded/ebin/prim_zip.beam
index ccf8aff6f6..cd41f36413 100644
--- a/erts/preloaded/ebin/prim_zip.beam
+++ b/erts/preloaded/ebin/prim_zip.beam
diff --git a/erts/preloaded/ebin/zlib.beam b/erts/preloaded/ebin/zlib.beam
index ccd597ba68..ce1163d260 100644
--- a/erts/preloaded/ebin/zlib.beam
+++ b/erts/preloaded/ebin/zlib.beam
diff --git a/erts/preloaded/src/prim_file.erl b/erts/preloaded/src/prim_file.erl
index 43e6f6cd88..2d177bf80e 100644
--- a/erts/preloaded/src/prim_file.erl
+++ b/erts/preloaded/src/prim_file.erl
@@ -1,19 +1,19 @@
 %%
 %% %CopyrightBegin%
-%% 
-%% Copyright Ericsson AB 2000-2009. All Rights Reserved.
-%% 
+%%
+%% Copyright Ericsson AB 2000-2010. All Rights Reserved.
+%%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
 %% compliance with the License. You should have received a copy of the
 %% Erlang Public License along with this software. If not, it can be
 %% retrieved online at http://www.erlang.org/.
-%% 
+%%
 %% Software distributed under the License is distributed on an "AS IS"
 %% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
 %% the License for the specific language governing rights and limitations
 %% under the License.
-%% 
+%%
 %% %CopyrightEnd%
 %%
 -module(prim_file).
@@ -25,7 +25,7 @@
 %%% Interface towards a single file's contents. Uses ?FD_DRV.
 
 %% Generic file contents operations
--export([open/2, close/1, sync/1, position/2, truncate/1,
+-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]).
 
 %% Specialized file operations
@@ -96,6 +96,8 @@
 -define(FILE_IPREAD,           27).
 -define(FILE_ALTNAME,          28).
 -define(FILE_READ_LINE,        29).
+-define(FILE_FDATASYNC,        30).
+-define(FILE_ADVISE,           31).
 
 %% Driver responses
 -define(FILE_RESP_OK,          0).
@@ -130,6 +132,13 @@
 %% IPREAD variants
 -define(IPREAD_S32BU_P32BU, 0).
 
+%% POSIX file advises
+-define(POSIX_FADV_NORMAL,     0).
+-define(POSIX_FADV_RANDOM,     1).
+-define(POSIX_FADV_SEQUENTIAL, 2).
+-define(POSIX_FADV_WILLNEED,   3).
+-define(POSIX_FADV_DONTNEED,   4).
+-define(POSIX_FADV_NOREUSE,    5).
 
 
 %%%-----------------------------------------------------------------
@@ -220,7 +229,35 @@ close(#file_descriptor{module = ?MODULE, data = {Port, _}}) ->
 close(Port) when is_port(Port) ->
     drv_close(Port).
 
+-define(ADVISE(Offs, Len, Adv),
+	<<?FILE_ADVISE, Offs:64/signed, Len:64/signed,
+	  Adv:32/signed>>).
 
+%% Returns {error, Reason} | ok.
+advise(#file_descriptor{module = ?MODULE, data = {Port, _}},
+       Offset, Length, Advise) ->
+    case Advise of
+	normal ->
+	    Cmd = ?ADVISE(Offset, Length, ?POSIX_FADV_NORMAL),
+	    drv_command(Port, Cmd);
+	random ->
+	    Cmd = ?ADVISE(Offset, Length, ?POSIX_FADV_RANDOM),
+	    drv_command(Port, Cmd);
+	sequential ->
+	    Cmd = ?ADVISE(Offset, Length, ?POSIX_FADV_SEQUENTIAL),
+	    drv_command(Port, Cmd);
+	will_need ->
+	    Cmd = ?ADVISE(Offset, Length, ?POSIX_FADV_WILLNEED),
+	    drv_command(Port, Cmd);
+	dont_need ->
+	    Cmd = ?ADVISE(Offset, Length, ?POSIX_FADV_DONTNEED),
+	    drv_command(Port, Cmd);
+	no_reuse ->
+	    Cmd = ?ADVISE(Offset, Length, ?POSIX_FADV_NOREUSE),
+	    drv_command(Port, Cmd);
+	_ ->
+	    {error, einval}
+    end.
 
 %% Returns {error, Reason} | ok.
 write(#file_descriptor{module = ?MODULE, data = {Port, _}}, Bytes) ->
@@ -292,6 +329,9 @@ pwrite(#file_descriptor{module = ?MODULE}, _, _) ->
     {error, badarg}.
 
 
+%% Returns {error, Reason} | ok.
+datasync(#file_descriptor{module = ?MODULE, data = {Port, _}}) ->
+    drv_command(Port, [?FILE_FDATASYNC]).
 
 %% Returns {error, Reason} | ok.
 sync(#file_descriptor{module = ?MODULE, data = {Port, _}}) ->