1------------------------------------------------------------------------------
2--                                                                          --
3--                         GNAT RUN-TIME COMPONENTS                         --
4--                                                                          --
5--    A D A . W I D E _ W I D E _ T E X T _ I O . G E N E R I C _ A U X     --
6--                                                                          --
7--                                 S p e c                                  --
8--                                                                          --
9--          Copyright (C) 1992-2019, Free Software Foundation, Inc.         --
10--                                                                          --
11-- GNAT is free software;  you can  redistribute it  and/or modify it under --
12-- terms of the  GNU General Public License as published  by the Free Soft- --
13-- ware  Foundation;  either version 3,  or (at your option) any later ver- --
14-- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
15-- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
16-- or FITNESS FOR A PARTICULAR PURPOSE.                                     --
17--                                                                          --
18-- As a special exception under Section 7 of GPL version 3, you are granted --
19-- additional permissions described in the GCC Runtime Library Exception,   --
20-- version 3.1, as published by the Free Software Foundation.               --
21--                                                                          --
22-- You should have received a copy of the GNU General Public License and    --
23-- a copy of the GCC Runtime Library Exception along with this program;     --
24-- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    --
25-- <http://www.gnu.org/licenses/>.                                          --
26--                                                                          --
27-- GNAT was originally developed  by the GNAT team at  New York University. --
28-- Extensive contributions were provided by Ada Core Technologies Inc.      --
29--                                                                          --
30------------------------------------------------------------------------------
31
32--  This package contains a set of auxiliary routines used by Wide_Wide_Text_IO
33--  generic children, including for reading and writing numeric strings.
34
35--  Note: although this is the Wide version of the package, the interface here
36--  is still in terms of Character and String rather than Wide_Wide_Character
37--  and Wide_Wide_String, since all numeric strings are composed entirely of
38--  characters in the range of type Standard.Character, and the basic
39--  conversion routines work with Character rather than Wide_Wide_Character.
40
41package Ada.Wide_Wide_Text_IO.Generic_Aux is
42
43   --  Note: for all the Load routines, File indicates the file to be read,
44   --  Buf is the string into which data is stored, Ptr is the index of the
45   --  last character stored so far, and is updated if additional characters
46   --  are stored. Data_Error is raised if the input overflows Buf. The only
47   --  Load routines that do a file status check are Load_Skip and Load_Width
48   --  so one of these two routines must be called first.
49
50   procedure Check_End_Of_Field
51     (Buf   : String;
52      Stop  : Integer;
53      Ptr   : Integer;
54      Width : Field);
55   --  This routine is used after doing a get operations on a numeric value.
56   --  Buf is the string being scanned, and Stop is the last character of
57   --  the field being scanned. Ptr is as set by the call to the scan routine
58   --  that scanned out the numeric value, i.e. it points one past the last
59   --  character scanned, and Width is the width parameter from the Get call.
60   --
61   --  There are two cases, if Width is non-zero, then a check is made that
62   --  the remainder of the field is all blanks. If Width is zero, then it
63   --  means that the scan routine scanned out only part of the field. We
64   --  have already scanned out the field that the ACVC tests seem to expect
65   --  us to read (even if it does not follow the syntax of the type being
66   --  scanned, e.g. allowing negative exponents in integers, and underscores
67   --  at the end of the string), so we just raise Data_Error.
68
69   procedure Check_On_One_Line (File : File_Type; Length : Integer);
70   --  Check to see if item of length Integer characters can fit on
71   --  current line. Call New_Line if not, first checking that the
72   --  line length can accommodate Length characters, raise Layout_Error
73   --  if item is too large for a single line.
74
75   function Is_Blank (C : Character) return Boolean;
76   --  Determines if C is a blank (space or tab)
77
78   procedure Load_Width
79     (File  : File_Type;
80      Width : Field;
81      Buf   : out String;
82      Ptr   : in out Integer);
83   --  Loads exactly Width characters, unless a line mark is encountered first
84
85   procedure Load_Skip (File  : File_Type);
86   --  Skips leading blanks and line and page marks, if the end of file is
87   --  read without finding a non-blank character, then End_Error is raised.
88   --  Note: a blank is defined as a space or horizontal tab (RM A.10.6(5)).
89
90   procedure Load
91     (File   : File_Type;
92      Buf    : out String;
93      Ptr    : in out Integer;
94      Char   : Character;
95      Loaded : out Boolean);
96   --  If next character is Char, loads it, otherwise no characters are loaded
97   --  Loaded is set to indicate whether or not the character was found.
98
99   procedure Load
100     (File   : File_Type;
101      Buf    : out String;
102      Ptr    : in out Integer;
103      Char   : Character);
104   --  Same as above, but no indication if character is loaded
105
106   procedure Load
107     (File   : File_Type;
108      Buf    : out String;
109      Ptr    : in out Integer;
110      Char1  : Character;
111      Char2  : Character;
112      Loaded : out Boolean);
113   --  If next character is Char1 or Char2, loads it, otherwise no characters
114   --  are loaded. Loaded is set to indicate whether or not one of the two
115   --  characters was found.
116
117   procedure Load
118     (File   : File_Type;
119      Buf    : out String;
120      Ptr    : in out Integer;
121      Char1  : Character;
122      Char2  : Character);
123   --  Same as above, but no indication if character is loaded
124
125   procedure Load_Digits
126     (File   : File_Type;
127      Buf    : out String;
128      Ptr    : in out Integer;
129      Loaded : out Boolean);
130   --  Loads a sequence of zero or more decimal digits. Loaded is set if
131   --  at least one digit is loaded.
132
133   procedure Load_Digits
134     (File   : File_Type;
135      Buf    : out String;
136      Ptr    : in out Integer);
137   --  Same as above, but no indication if character is loaded
138
139   procedure Load_Extended_Digits
140     (File   : File_Type;
141      Buf    : out String;
142      Ptr    : in out Integer;
143      Loaded : out Boolean);
144   --  Like Load_Digits, but also allows extended digits a-f and A-F
145
146   procedure Load_Extended_Digits
147     (File   : File_Type;
148      Buf    : out String;
149      Ptr    : in out Integer);
150   --  Same as above, but no indication if character is loaded
151
152   procedure Put_Item (File : File_Type; Str : String);
153   --  This routine is like Wide_Wide_Text_IO.Put, except that it checks for
154   --  overflow of bounded lines, as described in (RM A.10.6(8)). It is used
155   --  for all output of numeric values and of enumeration values. Note that
156   --  the buffer is of type String. Put_Item deals with converting this to
157   --  Wide_Wide_Characters as required.
158
159   procedure Store_Char
160     (File : File_Type;
161      ch   : Integer;
162      Buf  : out String;
163      Ptr  : in out Integer);
164   --  Store a single character in buffer, checking for overflow and
165   --  adjusting the column number in the file to reflect the fact
166   --  that a character has been acquired from the input stream.
167   --  The pos value of the character to store is in ch on entry.
168
169   procedure String_Skip (Str : String; Ptr : out Integer);
170   --  Used in the Get from string procedures to skip leading blanks in the
171   --  string. Ptr is set to the index of the first non-blank. If the string
172   --  is all blanks, then the excption End_Error is raised, Note that blank
173   --  is defined as a space or horizontal tab (RM A.10.6(5)).
174
175   procedure Ungetc (ch : Integer; File : File_Type);
176   --  Pushes back character into stream, using ungetc. The caller has
177   --  checked that the file is in read status. Device_Error is raised
178   --  if the character cannot be pushed back. An attempt to push back
179   --  an end of file (EOF) is ignored.
180
181private
182   pragma Inline (Is_Blank);
183
184end Ada.Wide_Wide_Text_IO.Generic_Aux;
185