2009-10-30 Emmanuel Briot <briot@adacore.com>

	* make.adb, adaint.c, adaint.h, osint.adb, osint.ads, bcheck.adb
	(*_attr): new subprograms.
	(File_Length, File_Time_Stamp, Is_Writable_File): new subprograms
	(Read_Library_Info_From_Full, Full_Library_Info_Name,
	Full_Source_Name): Now benefit from a previous cache of the file
	attributes, to further save on system calls.
	(Smart_Find_File): now also cache the file attributes. This makes the
	package File_Stamp_Hash_Table useless, and it was removed.
	(Compile_Sources): create subprograms for the various steps of the main
	loop, for readibility and to avoid sharing variables between the
	various steps.

From-SVN: r153747

gcc/ada/ChangeLog

 2009-10-30  Emmanuel Briot  <briot@adacore.com>
 
+	* make.adb, adaint.c, adaint.h, osint.adb, osint.ads, bcheck.adb
+	(*_attr): new subprograms.
+	(File_Length, File_Time_Stamp, Is_Writable_File): new subprograms
+	(Read_Library_Info_From_Full, Full_Library_Info_Name,
+	Full_Source_Name): Now benefit from a previous cache of the file
+	attributes, to further save on system calls.
+	(Smart_Find_File): now also cache the file attributes. This makes the
+	package File_Stamp_Hash_Table useless, and it was removed.
+	(Compile_Sources): create subprograms for the various steps of the main
+	loop, for readibility and to avoid sharing variables between the
+	various steps.
+
+2009-10-30  Emmanuel Briot  <briot@adacore.com>
+
 	* make.adb, osint.adb, osint.ads (Library_File_Stamp): Removed, since
 	unused.
 	(Read_Library_Info_From_Full): New subprogram.

gcc/ada/adaint.h

@@ -68,6 +68,30 @@ typedef long long OS_Time;
 typedef long OS_Time;
 #endif
 
+/* A lazy cache for the attributes of a file. On some systems, a single call to
+   stat() will give all this information, so it is better than doing a system
+   call every time. On other systems this require several system calls.
+*/
+
+struct file_attributes {
+  short exists;
+
+  short writable;
+  short readable;
+  short executable;
+
+  short symbolic_link;
+  short regular;
+  short directory;
+
+  OS_Time timestamp;
+  long file_length;
+};
+/* WARNING: changing the size here might require changing the constant
+ * File_Attributes_Size in osint.ads (which should be big enough to
+ * fit the above struct on any system)
+ */
+
 extern int    __gnat_max_path_len;
 extern OS_Time __gnat_current_time		   (void);
 extern void   __gnat_current_time_string           (char *);
@@ -121,15 +145,28 @@ extern OS_Time __gnat_file_time_fd                  (int);
 
 extern void   __gnat_set_file_time_name		   (char *, time_t);
 
-extern int    __gnat_dup			   (int);
-extern int    __gnat_dup2			   (int, int);
-extern int    __gnat_file_exists		   (char *);
-extern int    __gnat_is_regular_file               (char *);
-extern int    __gnat_is_absolute_path              (char *,int);
-extern int    __gnat_is_directory		   (char *);
+extern int    __gnat_dup			            (int);
+extern int    __gnat_dup2			            (int, int);
+extern int    __gnat_file_exists		         (char *);
+extern int    __gnat_is_regular_file         (char *);
+extern int    __gnat_is_absolute_path        (char *,int);
+extern int    __gnat_is_directory		      (char *);
 extern int    __gnat_is_writable_file		   (char *);
 extern int    __gnat_is_readable_file		   (char *name);
-extern int    __gnat_is_executable_file            (char *name);
+extern int    __gnat_is_executable_file      (char *name);
+
+extern void reset_attributes (struct file_attributes* attr);
+extern long   __gnat_file_length_attr        (int, char *, struct file_attributes *);
+extern OS_Time __gnat_file_time_name_attr    (char *, struct file_attributes *);
+extern OS_Time __gnat_file_time_fd_attr      (int,    struct file_attributes *);
+extern int    __gnat_file_exists_attr        (char *, struct file_attributes *);
+extern int    __gnat_is_regular_file_attr    (char *, struct file_attributes *);
+extern int    __gnat_is_directory_attr       (char *, struct file_attributes *);
+extern int    __gnat_is_readable_file_attr   (char *, struct file_attributes *);
+extern int    __gnat_is_writable_file_attr   (char *, struct file_attributes *);
+extern int    __gnat_is_executable_file_attr (char *, struct file_attributes *);
+extern int    __gnat_is_symbolic_link_attr   (char *, struct file_attributes *);
+
 extern void   __gnat_set_non_writable              (char *name);
 extern void   __gnat_set_writable                  (char *name);
 extern void   __gnat_set_executable                (char *name);

gcc/ada/bcheck.adb

@@ -190,7 +190,7 @@ package body Bcheck is
 
                else
                   ALI_Path_Id :=
-                    Osint.Find_File ((ALIs.Table (A).Afile), Osint.Library);
+                    Osint.Full_Lib_File_Name (ALIs.Table (A).Afile);
                   if Osint.Is_Readonly_Library (ALI_Path_Id) then
                      if Tolerate_Consistency_Errors then
                         Error_Msg ("?{ should be recompiled");

gcc/ada/osint.ads

@@ -29,6 +29,7 @@
 with Namet; use Namet;
 with Types; use Types;
 
+with System.Storage_Elements;
 with System.OS_Lib; use System.OS_Lib;
 with System;        use System;
 
@@ -230,6 +231,47 @@ package Osint is
    --  this routine called with Name set to "gnat" will return "-lgnat-5.02"
    --  on UNIX and Windows and -lgnat_5_02 on VMS.
 
+   ---------------------
+   -- File attributes --
+   ---------------------
+   --  The following subprograms offer services similar to those found in
+   --  System.OS_Lib, but with the ability to extra multiple information from
+   --  a single system call, depending on the system. This can result in fewer
+   --  system calls when reused.
+   --  In all these subprograms, the requested value is either read from the
+   --  File_Attributes parameter (resulting in no system call), or computed
+   --  from the disk and then cached in the File_Attributes parameter (possibly
+   --  along with other values).
+
+   type File_Attributes is private;
+   Unknown_Attributes : constant File_Attributes;
+   --  A cache for various attributes for a file (length, accessibility,...)
+   --  This must be initialized to Unknown_Attributes prior to the first call.
+
+   function Is_Directory
+     (Name : C_File_Name; Attr : access File_Attributes) return Boolean;
+   function Is_Regular_File
+     (Name : C_File_Name; Attr : access File_Attributes) return Boolean;
+   function Is_Symbolic_Link
+     (Name : C_File_Name; Attr : access File_Attributes) return Boolean;
+   --  Return the type of the file,
+
+   function File_Length
+     (Name : C_File_Name; Attr : access File_Attributes) return Long_Integer;
+   --  Return the length (number of bytes) of the file
+
+   function File_Time_Stamp
+     (Name : C_File_Name; Attr : access File_Attributes) return OS_Time;
+   --  Return the time stamp of the file
+
+   function Is_Readable_File
+     (Name : C_File_Name; Attr : access File_Attributes) return Boolean;
+   function Is_Executable_File
+     (Name : C_File_Name; Attr : access File_Attributes) return Boolean;
+   function Is_Writable_File
+     (Name : C_File_Name; Attr : access File_Attributes) return Boolean;
+   --  Return the access rights for the file
+
    -------------------------
    -- Search Dir Routines --
    -------------------------
@@ -380,6 +422,10 @@ package Osint is
    --  using Read_Source_File. Calling this routine entails no source file
    --  directory lookup penalty.
 
+   procedure Full_Source_Name
+     (N         : File_Name_Type;
+      Full_File : out File_Name_Type;
+      Attr      : access File_Attributes);
    function Full_Source_Name (N : File_Name_Type) return File_Name_Type;
    function Source_File_Stamp (N : File_Name_Type) return Time_Stamp_Type;
    --  Returns the full name/time stamp of the source file whose simple name
@@ -390,6 +436,8 @@ package Osint is
    --  The source file directory lookup penalty is incurred every single time
    --  the routines are called unless you have previously called
    --  Source_File_Data (Cache => True). See below.
+   --  The procedural version also returns some file attributes for the ALI
+   --  file (to save on system calls later on).
 
    function Current_File_Index return Int;
    --  Return the index in its source file of the current main unit
@@ -488,10 +536,14 @@ package Osint is
 
    function Read_Library_Info_From_Full
      (Full_Lib_File : File_Name_Type;
+      Lib_File_Attr : access File_Attributes;
       Fatal_Err     : Boolean := False) return Text_Buffer_Ptr;
    --  Same as Read_Library_Info, except Full_Lib_File must contains the full
    --  path to the library file (instead of having Read_Library_Info recompute
-   --  it)
+   --  it).
+   --  Lib_File_Attr should be an initialized set of attributes for the
+   --  library file (it can be initialized to Unknown_Attributes, but in
+   --  general will have been initialized by a previous call to Find_File).
 
    function Full_Library_Info_Name return File_Name_Type;
    function Full_Object_File_Name return File_Name_Type;
@@ -508,6 +560,10 @@ package Osint is
    --  It is an error to call Current_Object_File_Stamp if
    --  Opt.Check_Object_Consistency is set to False.
 
+   procedure Full_Lib_File_Name
+     (N        : File_Name_Type;
+      Lib_File : out File_Name_Type;
+      Attr     : out File_Attributes);
    function Full_Lib_File_Name (N : File_Name_Type) return File_Name_Type;
    --  Returns the full name of library file N. N should not include
    --  path information. Note that if the file cannot be located No_File is
@@ -515,6 +571,8 @@ package Osint is
    --  for the second (this is not an error situation). The full name includes
    --  the appropriate directory information. The library file directory lookup
    --  penalty is incurred every single time this routine is called.
+   --  The procedural version also returns some file attributes for the ALI
+   --  file (to save on system calls later on).
 
    function Lib_File_Name
      (Source_File : File_Name_Type;
@@ -660,4 +718,18 @@ private
    --  detected, the file being written is deleted, and a fatal error is
    --  signalled.
 
+   File_Attributes_Size : constant Integer := 50;
+   --  This should be big enough to fit a "struct file_attributes" on any
+   --  system. It doesn't matter if it is too big (which avoids the need for
+   --  either mapping the struct exactly or importing the sizeof from C, which
+   --  would result in dynamic code)
+
+   type File_Attributes is
+     array (1 .. File_Attributes_Size)
+     of System.Storage_Elements.Storage_Element;
+
+   Unknown_Attributes : constant File_Attributes := (others => 0);
+   --  Will be initialized properly at elaboration (for efficiency later on,
+   --  avoid function calls every time we want to reset the attributes).
+
 end Osint;