summaryrefslogtreecommitdiff
path: root/gcc/ada/stringt.ads
blob: 92b74e2c049e7e46a2afbff3895aad7dcb9c1f78 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
------------------------------------------------------------------------------
--                                                                          --
--                         GNAT COMPILER COMPONENTS                         --
--                                                                          --
--                              S T R I N G T                               --
--                                                                          --
--                                 S p e c                                  --
--                                                                          --
--          Copyright (C) 1992-2013, 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 3,  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.                                     --
--                                                                          --
-- As a special exception under Section 7 of GPL version 3, you are granted --
-- additional permissions described in the GCC Runtime Library Exception,   --
-- version 3.1, as published by the Free Software Foundation.               --
--                                                                          --
-- You should have received a copy of the GNU General Public License and    --
-- a copy of the GCC Runtime Library Exception along with this program;     --
-- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    --
-- <http://www.gnu.org/licenses/>.                                          --
--                                                                          --
-- GNAT was originally developed  by the GNAT team at  New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc.      --
--                                                                          --
------------------------------------------------------------------------------

with System; use System;
with Types;  use Types;

package Stringt is
   pragma Elaborate_Body;
   --  This is to make sure Null_String_Id is properly initialized

--  This package contains routines for handling the strings table which is
--  used to store string constants encountered in the source, and also those
--  additional string constants generated by compile time concatenation and
--  other similar processing.

--  A string constant in this table consists of a series of Char_Code values,
--  so that 16-bit character codes can be properly handled if this feature
--  is implemented in the scanner.

--  There is no guarantee that hashing is used in the implementation, although
--  it maybe. This means that the caller cannot count on having the same Id
--  value for two identical strings stored separately and also cannot count on
--  the two Id values being different.

   Null_String_Id : String_Id;
   --  Gets set to a null string with length zero

   --------------------------------------
   -- String Table Access Subprograms --
   --------------------------------------

   procedure Initialize;
   --  Initializes the strings table for a new compilation. Note that
   --  Initialize must not be called if Tree_Read is used.

   procedure Lock;
   --  Lock internal tables before calling back end

   procedure Unlock;
   --  Unlock internal tables, in case back end needs to modify them

   procedure Mark;
   --  Take a snapshot of the internal tables. Used in conjunction with Release
   --  when computing temporary string values that need not be preserved.

   procedure Release;
   --  Restore the internal tables to the situation when Mark was last called.
   --  If Release is called with no prior call to Mark, the entire string table
   --  is cleared to its initial (empty) setting.

   procedure Start_String;
   --  Sets up for storing a new string in the table. To store a string, a
   --  call is first made to Start_String, then successive calls are
   --  made to Store_String_Character to store the characters of the string.
   --  Finally, a call to End_String terminates the entry and returns it Id.

   procedure Start_String (S : String_Id);
   --  Like Start_String with no parameter, except that the contents of the
   --  new string is initialized to be a copy of the given string. A test is
   --  made to see if S is the last created string, and if so it is shared,
   --  rather than copied, this can be particularly helpful for the case of
   --  a continued concatenation of string constants.

   procedure Store_String_Char (C : Char_Code);
   procedure Store_String_Char (C : Character);
   --  Store next character of string, see description above for Start_String

   procedure Store_String_Chars (S : String);
   procedure Store_String_Chars (S : String_Id);
   --  Store character codes of given string in sequence

   procedure Store_String_Int (N : Int);
   --  Stored decimal representation of integer with possible leading minus

   procedure Unstore_String_Char;
   --  Undoes effect of previous Store_String_Char call, used in some error
   --  situations of unterminated string constants.

   function End_String return String_Id;
   --  Terminates current string and returns its Id

   function String_Length (Id : String_Id) return Nat;
   --  Returns length of previously stored string

   function Get_String_Char (Id : String_Id; Index : Int) return Char_Code;
   pragma Inline (Get_String_Char);
   --  Obtains the specified character from a stored string. The lower bound
   --  of stored strings is always 1, so the range is 1 .. String_Length (Id).

   function String_Equal (L, R : String_Id) return Boolean;
   --  Determines if two string literals represent the same string

   procedure String_To_Name_Buffer (S : String_Id);
   --  Place characters of given string in Name_Buffer, setting Name_Len.
   --  Error if any characters are out of Character range. Does not attempt
   --  to do any encoding of any characters.

   procedure Add_String_To_Name_Buffer (S : String_Id);
   --  Append characters of given string to Name_Buffer, updating Name_Len.
   --  Error if any characters are out of Character range. Does not attempt
   --  to do any encoding of any characters.

   function String_Chars_Address return System.Address;
   --  Return address of String_Chars table (used by Back_End call to Gigi)

   function String_From_Name_Buffer return String_Id;
   --  Given a name stored in Namet.Name_Buffer (length in Namet.Name_Len),
   --  returns a string of the corresponding value. The value in Name_Buffer
   --  is unchanged, and the cases of letters are unchanged.

   function Strings_Address return System.Address;
   --  Return address of Strings table (used by Back_End call to Gigi)

   procedure Tree_Read;
   --  Initializes internal tables from current tree file using the relevant
   --  Table.Tree_Read routines. Note that Initialize should not be called if
   --  Tree_Read is used. Tree_Read includes all necessary initialization.

   procedure Tree_Write;
   --  Writes out internal tables to current tree file using the relevant
   --  Table.Tree_Write routines.

   procedure Write_Char_Code (Code : Char_Code);
   --  Procedure to write a character code value, used for debugging purposes
   --  for writing character codes. If the character code is in the range
   --  16#20# .. 16#7E#, then the single graphic character corresponding to
   --  the code is output. For any other codes in the range 16#00# .. 16#FF#,
   --  the code is output as ["hh"] where hh is the two digit hex value for
   --  the code. Codes greater than 16#FF# are output as ["hhhh"] where hhhh
   --  is the four digit hex representation of the code value (high order
   --  byte first). Hex letters are always in lower case.

   procedure Write_String_Table_Entry (Id : String_Id);
   --  Writes a string value with enclosing quotes to the current file using
   --  routines in package Output. Does not write an end of line character.
   --  This procedure is used for debug output purposes, and also for output
   --  of strings specified by pragma Linker Option to the ali file. 7-bit
   --  ASCII graphics (except for double quote) are output literally.
   --  The double quote appears as two successive double quotes.
   --  All other codes, are output as described for Write_Char_Code. For
   --  example, the string created by folding "A" & ASCII.HT & "Hello" will
   --  print as "A["09"]Hello". A No_String value prints simply as "no string"
   --  without surrounding quote marks.

private
   pragma Inline (End_String);
   pragma Inline (String_Length);

end Stringt;