|  | ------------------------------------------------------------------------------ | 
|  | --                                                                          -- | 
|  | --                         GNAT COMPILER COMPONENTS                         -- | 
|  | --                                                                          -- | 
|  | --                               S I N P U T                                -- | 
|  | --                                                                          -- | 
|  | --                                 S p e c                                  -- | 
|  | --                                                                          -- | 
|  | --          Copyright (C) 1992-2006, Free Software Foundation, Inc.         -- | 
|  | --                                                                          -- | 
|  | -- GNAT is free software;  you can  redistribute it  and/or modify it under -- | 
|  | -- terms of the  GNU General Public License as published  by the Free Soft- -- | 
|  | -- ware  Foundation;  either version 2,  or (at your option) any later ver- -- | 
|  | -- sion.  GNAT is distributed in the hope that it will be useful, but WITH- -- | 
|  | -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY -- | 
|  | -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License -- | 
|  | -- for  more details.  You should have  received  a copy of the GNU General -- | 
|  | -- Public License  distributed with GNAT;  see file COPYING.  If not, write -- | 
|  | -- to  the  Free Software Foundation,  51  Franklin  Street,  Fifth  Floor, -- | 
|  | -- Boston, MA 02110-1301, USA.                                              -- | 
|  | --                                                                          -- | 
|  | -- As a special exception,  if other files  instantiate  generics from this -- | 
|  | -- unit, or you link  this unit with other files  to produce an executable, -- | 
|  | -- this  unit  does not  by itself cause  the resulting  executable  to  be -- | 
|  | -- covered  by the  GNU  General  Public  License.  This exception does not -- | 
|  | -- however invalidate  any other reasons why  the executable file  might be -- | 
|  | -- covered by the  GNU Public License.                                      -- | 
|  | --                                                                          -- | 
|  | -- GNAT was originally developed  by the GNAT team at  New York University. -- | 
|  | -- Extensive contributions were provided by Ada Core Technologies Inc.      -- | 
|  | --                                                                          -- | 
|  | ------------------------------------------------------------------------------ | 
|  |  | 
|  | --  This package contains the input routines used for reading the | 
|  | --  input source file. The actual I/O routines are in OS_Interface, | 
|  | --  with this module containing only the system independent processing. | 
|  |  | 
|  | --  General Note: throughout the compiler, we use the term line or source | 
|  | --  line to refer to a physical line in the source, terminated by the end of | 
|  | --  physical line sequence. | 
|  |  | 
|  | --  There are two distinct concepts of line terminator in GNAT | 
|  |  | 
|  | --    A logical line terminator is what corresponds to the "end of a line" as | 
|  | --    described in RM 2.2 (13). Any of the characters FF, LF, CR or VT or any | 
|  | --    wide character that is a Line or Paragraph Separator acts as an end of | 
|  | --    logical line in this sense, and it is essentially irrelevant whether one | 
|  | --    or more appears in sequence (since if sequence of such characters is | 
|  | --    regarded as separate ends of line, then the intervening logical lines | 
|  | --    are null in any case). | 
|  |  | 
|  | --    A physical line terminator is a sequence of format effectors that is | 
|  | --    treated as ending a physical line. Physical lines have no Ada semantic | 
|  | --    significance, but they are significant for error reporting purposes, | 
|  | --    since errors are identified by line and column location. | 
|  |  | 
|  | --  In GNAT, a physical line is ended by any of the sequences LF, CR/LF, CR or | 
|  | --  LF/CR. LF is used in typical Unix systems, CR/LF in DOS systems, and CR | 
|  | --  alone in System 7. We don't know of any system using LF/CR, but it seems | 
|  | --  reasonable to include this case for consistency. In addition, we recognize | 
|  | --  any of these sequences in any of the operating systems, for better | 
|  | --  behavior in treating foreign files (e.g. a Unix file with LF terminators | 
|  | --  transferred to a DOS system). Finally, wide character codes in cagtegories | 
|  | --  Separator, Line and Separator, Paragraph are considered to be physical | 
|  | --  line terminators. | 
|  |  | 
|  | with Alloc; | 
|  | with Casing; use Casing; | 
|  | with Table; | 
|  | with Types;  use Types; | 
|  |  | 
|  | package Sinput is | 
|  |  | 
|  | type Type_Of_File is ( | 
|  | --  Indicates type of file being read | 
|  |  | 
|  | Src, | 
|  | --  Normal Ada source file | 
|  |  | 
|  | Config, | 
|  | --  Configuration pragma file | 
|  |  | 
|  | Def, | 
|  | --  Preprocessing definition file | 
|  |  | 
|  | Preproc); | 
|  | --  Source file with preprocessing commands to be preprocessed | 
|  |  | 
|  | ---------------------------- | 
|  | -- Source License Control -- | 
|  | ---------------------------- | 
|  |  | 
|  | --  The following type indicates the license state of a source if it | 
|  | --  is known. | 
|  |  | 
|  | type License_Type is | 
|  | (Unknown, | 
|  | --  Licensing status of this source unit is unknown | 
|  |  | 
|  | Restricted, | 
|  | --  This is a non-GPL'ed unit that is restricted from depending | 
|  | --  on GPL'ed units (e.g. proprietary code is in this category) | 
|  |  | 
|  | GPL, | 
|  | --  This file is licensed under the unmodified GPL. It is not allowed | 
|  | --  to depend on Non_GPL units, and Non_GPL units may not depend on | 
|  | --  this source unit. | 
|  |  | 
|  | Modified_GPL, | 
|  | --  This file is licensed under the GNAT modified GPL (see header of | 
|  | --  This file for wording of the modification). It may depend on other | 
|  | --  Modified_GPL units or on unrestricted units. | 
|  |  | 
|  | Unrestricted); | 
|  | --  The license on this file is permitted to depend on any other | 
|  | --  units, or have other units depend on it, without violating the | 
|  | --  license of this unit. Examples are public domain units, and | 
|  | --  units defined in the RM). | 
|  |  | 
|  | --  The above license status is checked when the appropriate check is | 
|  | --  activated and one source depends on another, and the licensing state | 
|  | --  of both files is known: | 
|  |  | 
|  | --  The prohibited combinations are: | 
|  |  | 
|  | --    Restricted file may not depend on GPL file | 
|  |  | 
|  | --    GPL file may not depend on Restricted file | 
|  |  | 
|  | --    Modified GPL file may not depend on Restricted file | 
|  | --    Modified_GPL file may not depend on GPL file | 
|  |  | 
|  | --  The reason for the last restriction here is that a client depending | 
|  | --  on a modified GPL file must be sure that the license condition is | 
|  | --  correct considered transitively. | 
|  |  | 
|  | --  The licensing status is determined either by the presence of a | 
|  | --  specific pragma License, or by scanning the header for a predefined | 
|  | --  file, or any file if compiling in -gnatg mode. | 
|  |  | 
|  | ----------------------- | 
|  | -- Source File Table -- | 
|  | ----------------------- | 
|  |  | 
|  | --  The source file table has an entry for each source file read in for | 
|  | --  this run of the compiler. This table is (default) initialized when | 
|  | --  the compiler is loaded, and simply accumulates entries as compilation | 
|  | --  proceeds and various routines in Sinput and its child packages are | 
|  | --  called to load required source files. | 
|  |  | 
|  | --  Virtual entries are also created for generic templates when they are | 
|  | --  instantiated, as described in a separate section later on. | 
|  |  | 
|  | --  In the case where there are multiple main units (e.g. in the case of | 
|  | --  the cross-reference tool), this table is not reset between these units, | 
|  | --  so that a given source file is only read once if it is used by two | 
|  | --  separate main units. | 
|  |  | 
|  | --  The entries in the table are accessed using a Source_File_Index that | 
|  | --  ranges from 1 to Last_Source_File. Each entry has the following fields | 
|  |  | 
|  | --  Note: fields marked read-only are set by Sinput or one of its child | 
|  | --  packages when a source file table entry is created, and cannot be | 
|  | --  subsqently modified, or alternatively are set only by very special | 
|  | --  circumstances, documented in the comments. | 
|  |  | 
|  | --  File_Name : File_Name_Type (read-only) | 
|  | --    Name of the source file (simple name with no directory information) | 
|  |  | 
|  | --  Full_File_Name : File_Name_Type (read-only) | 
|  | --    Full file name (full name with directory info), used for generation | 
|  | --    of error messages, etc. | 
|  |  | 
|  | --  File_Type : Type_Of_File (read-only) | 
|  | --    Indicates type of file (source file, configuration pragmas file, | 
|  | --    preprocessor definition file, preprocessor input file). | 
|  |  | 
|  | --  Reference_Name : File_Name_Type (read-only) | 
|  | --    Name to be used for source file references in error messages where | 
|  | --    only the simple name of the file is required. Identical to File_Name | 
|  | --    unless pragma Source_Reference is used to change it. Only processing | 
|  | --    for the Source_Reference pragma circuit may set this field. | 
|  |  | 
|  | --  Full_Ref_Name : File_Name_Type (read-only) | 
|  | --    Name to be used for source file references in error messages where | 
|  | --    the full name of the file is required. Identical to Full_File_Name | 
|  | --    unless pragma Source_Reference is used to change it. Only processing | 
|  | --    for the Source_Reference pragma may set this field. | 
|  |  | 
|  | --  Debug_Source_Name : File_Name_Type (read-only) | 
|  | --    Name to be used for source file references in debugging information | 
|  | --    where only the simple name of the file is required. Identical to | 
|  | --    Reference_Name unless the -gnatD (debug source file) switch is used. | 
|  | --    Only processing in Sprint that generates this file is permitted to | 
|  | --    set this field. | 
|  |  | 
|  | --  Full_Debug_Name : File_Name_Type (read-only) | 
|  | --    Name to be used for source file references in debugging information | 
|  | --    where the full name of the file is required. This is identical to | 
|  | --    Full_Ref_Name unless the -gnatD (debug source file) switch is used. | 
|  | --    Only processing in Sprint that generates this file is permitted to | 
|  | --    set this field. | 
|  |  | 
|  | --  License : License_Type; | 
|  | --    License status of source file | 
|  |  | 
|  | --  Num_SRef_Pragmas : Nat; | 
|  | --    Number of source reference pragmas present in source file | 
|  |  | 
|  | --  First_Mapped_Line : Logical_Line_Number; | 
|  | --    This field stores logical line number of the first line in the | 
|  | --    file that is not a Source_Reference pragma. If no source reference | 
|  | --    pragmas are used, then the value is set to No_Line_Number. | 
|  |  | 
|  | --  Source_Text : Source_Buffer_Ptr (read-only) | 
|  | --    Text of source file. Note that every source file has a distinct set | 
|  | --    of non-overlapping logical bounds, so it is possible to determine | 
|  | --    which file is referenced from a given subscript (Source_Ptr) value. | 
|  |  | 
|  | --  Source_First : Source_Ptr; (read-only) | 
|  | --    Subscript of first character in Source_Text. Note that this cannot | 
|  | --    be obtained as Source_Text'First, because we use virtual origin | 
|  | --    addressing. | 
|  |  | 
|  | --  Source_Last : Source_Ptr; (read-only) | 
|  | --    Subscript of last character in Source_Text. Note that this cannot | 
|  | --    be obtained as Source_Text'Last, because we use virtual origin | 
|  | --    addressing, so this value is always Source_Ptr'Last. | 
|  |  | 
|  | --  Time_Stamp : Time_Stamp_Type; (read-only) | 
|  | --    Time stamp of the source file | 
|  |  | 
|  | --  Source_Checksum : Word; | 
|  | --    Computed checksum for contents of source file. See separate section | 
|  | --    later on in this spec for a description of the checksum algorithm. | 
|  |  | 
|  | --  Last_Source_Line : Physical_Line_Number; | 
|  | --    Physical line number of last source line. Whlie a file is being | 
|  | --    read, this refers to the last line scanned. Once a file has been | 
|  | --    completely scanned, it is the number of the last line in the file, | 
|  | --    and hence also gives the number of source lines in the file. | 
|  |  | 
|  | --  Keyword_Casing : Casing_Type; | 
|  | --    Casing style used in file for keyword casing. This is initialized | 
|  | --    to Unknown, and then set from the first occurrence of a keyword. | 
|  | --    This value is used only for formatting of error messages. | 
|  |  | 
|  | --  Identifier_Casing : Casing_Type; | 
|  | --    Casing style used in file for identifier casing. This is initialized | 
|  | --    to Unknown, and then set from an identifier in the program as soon as | 
|  | --    one is found whose casing is sufficiently clear to make a decision. | 
|  | --    This value is used for formatting of error messages, and also is used | 
|  | --    in the detection of keywords misused as identifiers. | 
|  |  | 
|  | --  Instantiation : Source_Ptr; | 
|  | --    Source file location of the instantiation if this source file entry | 
|  | --    represents a generic instantiation. Set to No_Location for the case | 
|  | --    of a normal non-instantiation entry. See section below for details. | 
|  | --    This field is read-only for clients. | 
|  |  | 
|  | --  Inlined_Body : Boolean; | 
|  | --    This can only be set True if Instantiation has a value other than | 
|  | --    No_Location. If true it indicates that the instantiation is actually | 
|  | --    an instance of an inlined body. | 
|  |  | 
|  | --  Template : Source_File_Index; (read-only) | 
|  | --    Source file index of the source file containing the template if this | 
|  | --    is a generic instantiation. Set to No_Source_File for the normal case | 
|  | --    of a non-instantiation entry. See Sinput-L for details. | 
|  |  | 
|  | --  Unit : Unit_Number_Type; | 
|  | --    Identifies the unit contained in this source file. Set by | 
|  | --    Initialize_Scanner, must not be subsequently altered. | 
|  |  | 
|  | --  The source file table is accessed by clients using the following | 
|  | --  subprogram interface: | 
|  |  | 
|  | subtype SFI is Source_File_Index; | 
|  |  | 
|  | System_Source_File_Index : SFI; | 
|  | --  The file system.ads is always read by the compiler to determine the | 
|  | --  settings of the target parameters in the private part of System. This | 
|  | --  variable records the source file index of system.ads. Typically this | 
|  | --  will be 1 since system.ads is read first. | 
|  |  | 
|  | function Debug_Source_Name (S : SFI) return File_Name_Type; | 
|  | function File_Name         (S : SFI) return File_Name_Type; | 
|  | function File_Type         (S : SFI) return Type_Of_File; | 
|  | function First_Mapped_Line (S : SFI) return Logical_Line_Number; | 
|  | function Full_Debug_Name   (S : SFI) return File_Name_Type; | 
|  | function Full_File_Name    (S : SFI) return File_Name_Type; | 
|  | function Full_Ref_Name     (S : SFI) return File_Name_Type; | 
|  | function Identifier_Casing (S : SFI) return Casing_Type; | 
|  | function Inlined_Body      (S : SFI) return Boolean; | 
|  | function Instantiation     (S : SFI) return Source_Ptr; | 
|  | function Keyword_Casing    (S : SFI) return Casing_Type; | 
|  | function Last_Source_Line  (S : SFI) return Physical_Line_Number; | 
|  | function License           (S : SFI) return License_Type; | 
|  | function Num_SRef_Pragmas  (S : SFI) return Nat; | 
|  | function Reference_Name    (S : SFI) return File_Name_Type; | 
|  | function Source_Checksum   (S : SFI) return Word; | 
|  | function Source_First      (S : SFI) return Source_Ptr; | 
|  | function Source_Last       (S : SFI) return Source_Ptr; | 
|  | function Source_Text       (S : SFI) return Source_Buffer_Ptr; | 
|  | function Template          (S : SFI) return Source_File_Index; | 
|  | function Unit              (S : SFI) return Unit_Number_Type; | 
|  | function Time_Stamp        (S : SFI) return Time_Stamp_Type; | 
|  |  | 
|  | procedure Set_Keyword_Casing    (S : SFI; C : Casing_Type); | 
|  | procedure Set_Identifier_Casing (S : SFI; C : Casing_Type); | 
|  | procedure Set_License           (S : SFI; L : License_Type); | 
|  | procedure Set_Unit              (S : SFI; U : Unit_Number_Type); | 
|  |  | 
|  | function Last_Source_File return Source_File_Index; | 
|  | --  Index of last source file table entry | 
|  |  | 
|  | function Num_Source_Files return Nat; | 
|  | --  Number of source file table entries | 
|  |  | 
|  | procedure Initialize; | 
|  | --  Initialize internal tables | 
|  |  | 
|  | procedure Lock; | 
|  | --  Lock internal tables | 
|  |  | 
|  | Main_Source_File : Source_File_Index := No_Source_File; | 
|  | --  This is set to the source file index of the main unit | 
|  |  | 
|  | ----------------------------- | 
|  | -- Source_File_Index_Table -- | 
|  | ----------------------------- | 
|  |  | 
|  | --  The Get_Source_File_Index function is called very frequently. Earlier | 
|  | --  versions cached a single entry, but then reverted to a serial search, | 
|  | --  and this proved to be a significant source of inefficiency. To get | 
|  | --  around this, we use the following directly indexed array. The space | 
|  | --  of possible input values is a value of type Source_Ptr which is simply | 
|  | --  an Int value. The values in this space are allocated sequentially as | 
|  | --  new units are loaded. | 
|  |  | 
|  | --  The following table has an entry for each 4K range of possible | 
|  | --  Source_Ptr values. The value in the table is the lowest value | 
|  | --  Source_File_Index whose Source_Ptr range contains value in the | 
|  | --  range. | 
|  |  | 
|  | --  For example, the entry with index 4 in this table represents Source_Ptr | 
|  | --  values in the range 4*4096 .. 5*4096-1. The Source_File_Index value | 
|  | --  stored would be the lowest numbered source file with at least one byte | 
|  | --  in this range. | 
|  |  | 
|  | --  The algorithm used in Get_Source_File_Index is simply to access this | 
|  | --  table and then do a serial search starting at the given position. This | 
|  | --  will almost always terminate with one or two checks. | 
|  |  | 
|  | --  Note that this array is pretty large, but in most operating systems | 
|  | --  it will not be allocated in physical memory unless it is actually used. | 
|  |  | 
|  | Chunk_Power : constant := 12; | 
|  | Chunk_Size  : constant := 2 ** Chunk_Power; | 
|  | --  Change comments above if value changed. Note that Chunk_Size must | 
|  | --  be a power of 2 (to allow for efficient access to the table). | 
|  |  | 
|  | Source_File_Index_Table : | 
|  | array (Int range 0 .. Int'Last / Chunk_Size) of Source_File_Index; | 
|  |  | 
|  | procedure Set_Source_File_Index_Table (Xnew : Source_File_Index); | 
|  | --  Sets entries in the Source_File_Index_Table for the newly created | 
|  | --  Source_File table entry whose index is Xnew. The Source_First and | 
|  | --  Source_Last fields of this entry must be set before the call. | 
|  |  | 
|  | ----------------------- | 
|  | -- Checksum Handling -- | 
|  | ----------------------- | 
|  |  | 
|  | --  As a source file is scanned, a checksum is computed by taking all the | 
|  | --  non-blank characters in the file, excluding comment characters, the | 
|  | --  minus-minus sequence starting a comment, and all control characters | 
|  | --  except ESC. | 
|  |  | 
|  | --  The checksum algorithm used is the standard CRC-32 algorithm, as | 
|  | --  implemented by System.CRC32, except that we do not bother with the | 
|  | --  final XOR with all 1 bits. | 
|  |  | 
|  | --  This algorithm ensures that the checksum includes all semantically | 
|  | --  significant aspects of the program represented by the source file, | 
|  | --  but is insensitive to layout, presence or contents of comments, wide | 
|  | --  character representation method, or casing conventions outside strings. | 
|  |  | 
|  | --  Scans.Checksum is initialized appropriately at the start of scanning | 
|  | --  a file, and copied into the Source_Checksum field of the file table | 
|  | --  entry when the end of file is encountered. | 
|  |  | 
|  | ------------------------------------- | 
|  | -- Handling Generic Instantiations -- | 
|  | ------------------------------------- | 
|  |  | 
|  | --  As described in Sem_Ch12, a generic instantiation involves making a | 
|  | --  copy of the tree of the generic template. The source locations in | 
|  | --  this tree directly reference the source of the template. However it | 
|  | --  is also possible to find the location of the instantiation. | 
|  |  | 
|  | --  This is achieved as follows. When an instantiation occurs, a new entry | 
|  | --  is made in the source file table. This entry points to the same source | 
|  | --  text, i.e. the file that contains the instantiation, but has a distinct | 
|  | --  set of Source_Ptr index values. The separate range of Sloc values avoids | 
|  | --  confusion, and means that the Sloc values can still be used to uniquely | 
|  | --  identify the source file table entry. It is possible for both entries | 
|  | --  to point to the same text, because of the virtual origin pointers used | 
|  | --  in the source table. | 
|  |  | 
|  | --  The Instantiation field of this source file index entry, usually set | 
|  | --  to No_Source_File, instead contains the Sloc of the instantiation. In | 
|  | --  the case of nested instantiations, this Sloc may itself refer to an | 
|  | --  instantiation, so the complete chain can be traced. | 
|  |  | 
|  | --  Two routines are used to build these special entries in the source | 
|  | --  file table. Create_Instantiation_Source is first called to build | 
|  | --  the virtual source table entry for the instantiation, and then the | 
|  | --  Sloc values in the copy are adjusted using Adjust_Instantiation_Sloc. | 
|  | --  See child unit Sinput.L for details on these two routines. | 
|  |  | 
|  | ----------------- | 
|  | -- Global Data -- | 
|  | ----------------- | 
|  |  | 
|  | Current_Source_File : Source_File_Index; | 
|  | --  Source_File table index of source file currently being scanned | 
|  |  | 
|  | Current_Source_Unit : Unit_Number_Type; | 
|  | --  Unit number of source file currently being scanned. The special value | 
|  | --  of No_Unit indicates that the configuration pragma file is currently | 
|  | --  being scanned (this has no entry in the unit table). | 
|  |  | 
|  | Source_gnat_adc : Source_File_Index := No_Source_File; | 
|  | --  This is set if a gnat.adc file is present to reference this file | 
|  |  | 
|  | Source : Source_Buffer_Ptr; | 
|  | --  Current source (copy of Source_File.Table (Current_Source_Unit).Source) | 
|  |  | 
|  | Internal_Source : aliased Source_Buffer (1 .. 81); | 
|  | --  This buffer is used internally in the compiler when the lexical analyzer | 
|  | --  is used to scan a string from within the compiler. The procedure is to | 
|  | --  establish Internal_Source_Ptr as the value of Source, set the string to | 
|  | --  be scanned, appropriately terminated, in this buffer, and set Scan_Ptr | 
|  | --  to point to the start of the buffer. It is a fatal error if the scanner | 
|  | --  signals an error while scanning a token in this internal buffer. | 
|  |  | 
|  | Internal_Source_Ptr : constant Source_Buffer_Ptr := | 
|  | Internal_Source'Unrestricted_Access; | 
|  | --  Pointer to internal source buffer | 
|  |  | 
|  | ----------------- | 
|  | -- Subprograms -- | 
|  | ----------------- | 
|  |  | 
|  | procedure Backup_Line (P : in out Source_Ptr); | 
|  | --  Back up the argument pointer to the start of the previous line. On | 
|  | --  entry, P points to the start of a physical line in the source buffer. | 
|  | --  On return, P is updated to point to the start of the previous line. | 
|  | --  The caller has checked that a Line_Terminator character precedes P so | 
|  | --  that there definitely is a previous line in the source buffer. | 
|  |  | 
|  | procedure Build_Location_String (Loc : Source_Ptr); | 
|  | --  This function builds a string literal of the form "name:line", | 
|  | --  where name is the file name corresponding to Loc, and line is | 
|  | --  the line number. In the event that instantiations are involved, | 
|  | --  additional suffixes of the same form are appended after the | 
|  | --  separating string " instantiated at ". The returned string is | 
|  | --  stored in Name_Buffer, terminated by ASCII.Nul, with Name_Length | 
|  | --  indicating the length not including the terminating Nul. | 
|  |  | 
|  | function Get_Column_Number (P : Source_Ptr) return Column_Number; | 
|  | --  The ones-origin column number of the specified Source_Ptr value is | 
|  | --  determined and returned. Tab characters if present are assumed to | 
|  | --  represent the standard 1,9,17.. spacing pattern. | 
|  |  | 
|  | function Get_Logical_Line_Number | 
|  | (P : Source_Ptr) return Logical_Line_Number; | 
|  | --  The line number of the specified source position is obtained by | 
|  | --  doing a binary search on the source positions in the lines table | 
|  | --  for the unit containing the given source position. The returned | 
|  | --  value is the logical line number, already adjusted for the effect | 
|  | --  of source reference pragmas. If P refers to the line of a source | 
|  | --  reference pragma itself, then No_Line is returned. If no source | 
|  | --  reference pragmas have been encountered, the value returned is | 
|  | --  the same as the physical line number. | 
|  |  | 
|  | function Get_Physical_Line_Number | 
|  | (P : Source_Ptr) return Physical_Line_Number; | 
|  | --  The line number of the specified source position is obtained by | 
|  | --  doing a binary search on the source positions in the lines table | 
|  | --  for the unit containing the given source position. The returned | 
|  | --  value is the physical line number in the source being compiled. | 
|  |  | 
|  | function Get_Source_File_Index (S : Source_Ptr) return Source_File_Index; | 
|  | --  Return file table index of file identified by given source pointer | 
|  | --  value. This call must always succeed, since any valid source pointer | 
|  | --  value belongs to some previously loaded source file. | 
|  |  | 
|  | function Instantiation_Depth (S : Source_Ptr) return Nat; | 
|  | --  Determine instantiation depth for given Sloc value. A value of | 
|  | --  zero means that the given Sloc is not in an instantiation. | 
|  |  | 
|  | function Line_Start (P : Source_Ptr) return Source_Ptr; | 
|  | --  Finds the source position of the start of the line containing the | 
|  | --  given source location. | 
|  |  | 
|  | function Line_Start | 
|  | (L : Physical_Line_Number; | 
|  | S : Source_File_Index) return Source_Ptr; | 
|  | --  Finds the source position of the start of the given line in the | 
|  | --  given source file, using a physical line number to identify the line. | 
|  |  | 
|  | function Num_Source_Lines (S : Source_File_Index) return Nat; | 
|  | --  Returns the number of source lines (this is equivalent to reading | 
|  | --  the value of Last_Source_Line, but returns Nat rathern than a | 
|  | --  physical line number. | 
|  |  | 
|  | procedure Register_Source_Ref_Pragma | 
|  | (File_Name          : Name_Id; | 
|  | Stripped_File_Name : Name_Id; | 
|  | Mapped_Line        : Nat; | 
|  | Line_After_Pragma  : Physical_Line_Number); | 
|  | --  Register a source reference pragma, the parameter File_Name is the | 
|  | --  file name from the pragma, and Stripped_File_Name is this name with | 
|  | --  the directory information stripped. Both these parameters are set | 
|  | --  to No_Name if no file name parameter was given in the pragma. | 
|  | --  (which can only happen for the second and subsequent pragmas). | 
|  | --  Mapped_Line is the line number parameter from the pragma, and | 
|  | --  Line_After_Pragma is the physical line number of the line that | 
|  | --  follows the line containing the Source_Reference pragma. | 
|  |  | 
|  | function Original_Location (S : Source_Ptr) return Source_Ptr; | 
|  | --  Given a source pointer S, returns the corresponding source pointer | 
|  | --  value ignoring instantiation copies. For locations that do not | 
|  | --  correspond to instantiation copies of templates, the argument is | 
|  | --  returned unchanged. For locations that do correspond to copies of | 
|  | --  templates from instantiations, the location within the original | 
|  | --  template is returned. This is useful in canonicalizing locations. | 
|  |  | 
|  | function Instantiation_Location (S : Source_Ptr) return Source_Ptr; | 
|  | pragma Inline (Instantiation_Location); | 
|  | --  Given a source pointer S, returns the corresponding source pointer | 
|  | --  value of the instantiation if this location is within an instance. | 
|  | --  If S is not within an instance, then this returns No_Location. | 
|  |  | 
|  | function Top_Level_Location (S : Source_Ptr) return Source_Ptr; | 
|  | --  Given a source pointer S, returns the argument unchanged if it is | 
|  | --  not in an instantiation. If S is in an instantiation, then it returns | 
|  | --  the location of the top level instantiation, i.e. the outer level | 
|  | --  instantiation in the nested case. | 
|  |  | 
|  | function Physical_To_Logical | 
|  | (Line : Physical_Line_Number; | 
|  | S    : Source_File_Index) return Logical_Line_Number; | 
|  | --  Given a physical line number in source file whose source index is S, | 
|  | --  return the corresponding logical line number. If the physical line | 
|  | --  number is one containing a Source_Reference pragma, the result will | 
|  | --  be No_Line_Number. | 
|  |  | 
|  | procedure Skip_Line_Terminators | 
|  | (P        : in out Source_Ptr; | 
|  | Physical : out Boolean); | 
|  | --  On entry, P points to a line terminator that has been encountered, | 
|  | --  which is one of FF,LF,VT,CR or a wide character sequence whose value is | 
|  | --  in category Separator,Line or Separator,Paragraph. The purpose of this | 
|  | --  P points just past the character that was scanned. The purpose of this | 
|  | --  routine is to distinguish physical and logical line endings. A physical | 
|  | --  line ending is one of: | 
|  | -- | 
|  | --     CR on its own (MAC System 7) | 
|  | --     LF on its own (Unix and unix-like systems) | 
|  | --     CR/LF (DOS, Windows) | 
|  | --     LF/CR (not used, but recognized in any case) | 
|  | --     Wide character in Separator,Line or Separator,Paragraph category | 
|  | -- | 
|  | --  A logical line ending (that is not a physical line ending) is one of: | 
|  | -- | 
|  | --     VT on its own | 
|  | --     FF on its own | 
|  | -- | 
|  | --  On return, P is bumped past the line ending sequence (one of the above | 
|  | --  seven possibilities). Physical is set to True to indicate that a | 
|  | --  physical end of line was encountered, in which case this routine also | 
|  | --  makes sure that the lines table for the current source file has an | 
|  | --  appropriate entry for the start of the new physical line. | 
|  |  | 
|  | function Source_Offset (S : Source_Ptr) return Nat; | 
|  | --  Returns the zero-origin offset of the given source location from the | 
|  | --  start of its corresponding unit. This is used for creating canonical | 
|  | --  names in some situations. | 
|  |  | 
|  | procedure Write_Location (P : Source_Ptr); | 
|  | --  Writes out a string of the form fff:nn:cc, where fff, nn, cc are the | 
|  | --  file name, line number and column corresponding to the given source | 
|  | --  location. No_Location and Standard_Location appear as the strings | 
|  | --  <no location> and <standard location>. If the location is within an | 
|  | --  instantiation, then the instance location is appended, enclosed in | 
|  | --  square brackets (which can nest if necessary). Note that this routine | 
|  | --  is used only for internal compiler debugging output purposes (which | 
|  | --  is why the somewhat cryptic use of brackets is acceptable). | 
|  |  | 
|  | procedure wl (P : Source_Ptr); | 
|  | pragma Export (Ada, wl); | 
|  | --  Equivalent to Write_Location (P); Write_Eol; for calls from GDB | 
|  |  | 
|  | procedure Write_Time_Stamp (S : Source_File_Index); | 
|  | --  Writes time stamp of specified file in YY-MM-DD HH:MM.SS format | 
|  |  | 
|  | procedure Tree_Read; | 
|  | --  Initializes internal tables from current tree file using the relevant | 
|  | --  Table.Tree_Read routines. | 
|  |  | 
|  | procedure Tree_Write; | 
|  | --  Writes out internal tables to current tree file using the relevant | 
|  | --  Table.Tree_Write routines. | 
|  |  | 
|  | private | 
|  | pragma Inline (File_Name); | 
|  | pragma Inline (First_Mapped_Line); | 
|  | pragma Inline (Full_File_Name); | 
|  | pragma Inline (Identifier_Casing); | 
|  | pragma Inline (Instantiation); | 
|  | pragma Inline (Keyword_Casing); | 
|  | pragma Inline (Last_Source_Line); | 
|  | pragma Inline (Last_Source_File); | 
|  | pragma Inline (License); | 
|  | pragma Inline (Num_SRef_Pragmas); | 
|  | pragma Inline (Num_Source_Files); | 
|  | pragma Inline (Num_Source_Lines); | 
|  | pragma Inline (Reference_Name); | 
|  | pragma Inline (Set_Keyword_Casing); | 
|  | pragma Inline (Set_Identifier_Casing); | 
|  | pragma Inline (Source_First); | 
|  | pragma Inline (Source_Last); | 
|  | pragma Inline (Source_Text); | 
|  | pragma Inline (Template); | 
|  | pragma Inline (Time_Stamp); | 
|  |  | 
|  | ------------------------- | 
|  | -- Source_Lines Tables -- | 
|  | ------------------------- | 
|  |  | 
|  | type Lines_Table_Type is | 
|  | array (Physical_Line_Number) of Source_Ptr; | 
|  | --  Type used for lines table. The entries are indexed by physical line | 
|  | --  numbers. The values are the starting Source_Ptr values for the start | 
|  | --  of the corresponding physical line. Note that we make this a bogus | 
|  | --  big array, sized as required, so that we avoid the use of fat pointers. | 
|  |  | 
|  | type Lines_Table_Ptr is access all Lines_Table_Type; | 
|  | --  Type used for pointers to line tables | 
|  |  | 
|  | type Logical_Lines_Table_Type is | 
|  | array (Physical_Line_Number) of Logical_Line_Number; | 
|  | --  Type used for logical lines table. This table is used if a source | 
|  | --  reference pragma is present. It is indexed by physical line numbers, | 
|  | --  and contains the corresponding logical line numbers. An entry that | 
|  | --  corresponds to a source reference pragma is set to No_Line_Number. | 
|  | --  Note that we make this a bogus big array, sized as required, so that | 
|  | --  we avoid the use of fat pointers. | 
|  |  | 
|  | type Logical_Lines_Table_Ptr is access all Logical_Lines_Table_Type; | 
|  | --  Type used for pointers to logical line tables | 
|  |  | 
|  | ----------------------- | 
|  | -- Source_File Table -- | 
|  | ----------------------- | 
|  |  | 
|  | --  See earlier descriptions for meanings of public fields | 
|  |  | 
|  | type Source_File_Record is record | 
|  |  | 
|  | File_Name         : File_Name_Type; | 
|  | File_Type         : Type_Of_File; | 
|  | Reference_Name    : File_Name_Type; | 
|  | Debug_Source_Name : File_Name_Type; | 
|  | Full_Debug_Name   : File_Name_Type; | 
|  | Full_File_Name    : File_Name_Type; | 
|  | Full_Ref_Name     : File_Name_Type; | 
|  | Inlined_Body      : Boolean; | 
|  | License           : License_Type; | 
|  | Num_SRef_Pragmas  : Nat; | 
|  | First_Mapped_Line : Logical_Line_Number; | 
|  | Source_Text       : Source_Buffer_Ptr; | 
|  | Source_First      : Source_Ptr; | 
|  | Source_Last       : Source_Ptr; | 
|  | Time_Stamp        : Time_Stamp_Type; | 
|  | Source_Checksum   : Word; | 
|  | Last_Source_Line  : Physical_Line_Number; | 
|  | Keyword_Casing    : Casing_Type; | 
|  | Identifier_Casing : Casing_Type; | 
|  | Instantiation     : Source_Ptr; | 
|  | Template          : Source_File_Index; | 
|  | Unit              : Unit_Number_Type; | 
|  |  | 
|  | --  The following fields are for internal use only (i.e. only in the | 
|  | --  body of Sinput or its children, with no direct access by clients). | 
|  |  | 
|  | Sloc_Adjust : Source_Ptr; | 
|  | --  A value to be added to Sloc values for this file to reference the | 
|  | --  corresponding lines table. This is zero for the non-instantiation | 
|  | --  case, and set so that the adition references the ultimate template | 
|  | --  for the instantiation case. See Sinput-L for further details. | 
|  |  | 
|  | Lines_Table : Lines_Table_Ptr; | 
|  | --  Pointer to lines table for this source. Updated as additional | 
|  | --  lines are accessed using the Skip_Line_Terminators procedure. | 
|  | --  Note: the lines table for an instantiation entry refers to the | 
|  | --  original line numbers of the template see Sinput-L for details. | 
|  |  | 
|  | Logical_Lines_Table : Logical_Lines_Table_Ptr; | 
|  | --  Pointer to logical lines table for this source. Non-null only if | 
|  | --  a source reference pragma has been processed. Updated as lines | 
|  | --  are accessed using the Skip_Line_Terminators procedure. | 
|  |  | 
|  | Lines_Table_Max : Physical_Line_Number; | 
|  | --  Maximum subscript values for currently allocated Lines_Table | 
|  | --  and (if present) the allocated Logical_Lines_Table. The value | 
|  | --  Max_Source_Line gives the maximum used value, this gives the | 
|  | --  maximum allocated value. | 
|  |  | 
|  | end record; | 
|  |  | 
|  | package Source_File is new Table.Table ( | 
|  | Table_Component_Type => Source_File_Record, | 
|  | Table_Index_Type     => Source_File_Index, | 
|  | Table_Low_Bound      => 1, | 
|  | Table_Initial        => Alloc.Source_File_Initial, | 
|  | Table_Increment      => Alloc.Source_File_Increment, | 
|  | Table_Name           => "Source_File"); | 
|  |  | 
|  | ----------------- | 
|  | -- Subprograms -- | 
|  | ----------------- | 
|  |  | 
|  | procedure Alloc_Line_Tables | 
|  | (S       : in out Source_File_Record; | 
|  | New_Max : Nat); | 
|  | --  Allocate or reallocate the lines table for the given source file so | 
|  | --  that it can accommodate at least New_Max lines. Also allocates or | 
|  | --  reallocates logical lines table if source ref pragmas are present. | 
|  |  | 
|  | procedure Add_Line_Tables_Entry | 
|  | (S : in out Source_File_Record; | 
|  | P : Source_Ptr); | 
|  | --  Increment line table size by one (reallocating the lines table if | 
|  | --  needed) and set the new entry to contain the value P. Also bumps | 
|  | --  the Source_Line_Count field. If source reference pragmas are | 
|  | --  present, also increments logical lines table size by one, and | 
|  | --  sets new entry. | 
|  |  | 
|  | procedure Trim_Lines_Table (S : Source_File_Index); | 
|  | --  Set lines table size for entry S in the source file table to | 
|  | --  correspond to the current value of Num_Source_Lines, releasing | 
|  | --  any unused storage. This is used by Sinput.L and Sinput.D. | 
|  |  | 
|  | end Sinput; |