1------------------------------------------------------------------------------ 2-- -- 3-- GNAT COMPILER COMPONENTS -- 4-- -- 5-- S T R I N G T -- 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 32with Namet; use Namet; 33with System; use System; 34with Types; use Types; 35 36package Stringt is 37 pragma Elaborate_Body; 38 -- This is to make sure Null_String_Id is properly initialized 39 40-- This package contains routines for handling the strings table which is 41-- used to store string constants encountered in the source, and also those 42-- additional string constants generated by compile time concatenation and 43-- other similar processing. 44 45-- WARNING: There is a C version of this package. Any changes to this 46-- source file must be properly reflected in the C header file stringt.h 47 48-- A string constant in this table consists of a series of Char_Code values, 49-- so that 16-bit character codes can be properly handled if this feature 50-- is implemented in the scanner. 51 52-- There is no guarantee that hashing is used in the implementation, although 53-- it may be. This means that the caller cannot count on having the same Id 54-- value for two identical strings stored separately and also cannot count on 55-- the two such Id values being different. 56 57 Null_String_Id : String_Id; 58 -- Gets set to a null string with length zero 59 60 -------------------------------------- 61 -- String Table Access Subprograms -- 62 -------------------------------------- 63 64 procedure Initialize; 65 -- Initializes the strings table for a new compilation. Note that 66 -- Initialize must not be called if Tree_Read is used. 67 68 procedure Lock; 69 -- Lock internal tables before calling back end 70 71 procedure Unlock; 72 -- Unlock internal tables, in case back end needs to modify them 73 74 procedure Mark; 75 -- Take a snapshot of the internal tables. Used in conjunction with Release 76 -- when computing temporary string values that need not be preserved. 77 78 procedure Release; 79 -- Restore the internal tables to the situation when Mark was last called. 80 -- If Release is called with no prior call to Mark, the entire string table 81 -- is cleared to its initial (empty) setting. 82 83 procedure Start_String; 84 -- Sets up for storing a new string in the table. To store a string, a 85 -- call is first made to Start_String, then successive calls are 86 -- made to Store_String_Character to store the characters of the string. 87 -- Finally, a call to End_String terminates the entry and returns it Id. 88 89 procedure Start_String (S : String_Id); 90 -- Like Start_String with no parameter, except that the contents of the 91 -- new string is initialized to be a copy of the given string. A test is 92 -- made to see if S is the last created string, and if so it is shared, 93 -- rather than copied, this can be particularly helpful for the case of 94 -- a continued concatenation of string constants. 95 96 procedure Store_String_Char (C : Char_Code); 97 procedure Store_String_Char (C : Character); 98 -- Store next character of string, see description above for Start_String 99 100 procedure Store_String_Chars (S : String); 101 procedure Store_String_Chars (S : String_Id); 102 -- Store character codes of given string in sequence 103 104 procedure Store_String_Int (N : Int); 105 -- Stored decimal representation of integer with possible leading minus 106 107 procedure Unstore_String_Char; 108 -- Undoes effect of previous Store_String_Char call, used in some error 109 -- situations of unterminated string constants. 110 111 function End_String return String_Id; 112 -- Terminates current string and returns its Id 113 114 function String_Length (Id : String_Id) return Nat; 115 -- Returns length of previously stored string 116 117 function Get_String_Char (Id : String_Id; Index : Int) return Char_Code; 118 pragma Inline (Get_String_Char); 119 -- Obtains the specified character from a stored string. The lower bound 120 -- of stored strings is always 1, so the range is 1 .. String_Length (Id). 121 122 function String_Equal (L, R : String_Id) return Boolean; 123 -- Determines if two string literals represent the same string 124 125 function String_To_Name (S : String_Id) return Name_Id; 126 -- Convert String_Id to Name_Id 127 128 procedure Append (Buf : in out Bounded_String; S : String_Id); 129 -- Append characters of given string to Buf. Error if any characters are 130 -- out of Character range. Does not attempt to do any encoding of 131 -- characters. 132 133 function To_String (S : String_Id) return String; 134 -- Return S as a String 135 136 procedure String_To_Name_Buffer (S : String_Id); 137 -- Place characters of given string in Name_Buffer, setting Name_Len. 138 -- Error if any characters are out of Character range. Does not attempt 139 -- to do any encoding of any characters. 140 141 function String_Chars_Address return System.Address; 142 -- Return address of String_Chars table (used by Back_End call to Gigi) 143 144 function String_From_Name_Buffer 145 (Buf : Bounded_String := Global_Name_Buffer) return String_Id; 146 -- Given a name stored in Buf, returns a string of the corresponding value. 147 148 function Strings_Address return System.Address; 149 -- Return address of Strings table (used by Back_End call to Gigi) 150 151 procedure Tree_Read; 152 -- Initializes internal tables from current tree file using the relevant 153 -- Table.Tree_Read routines. Note that Initialize should not be called if 154 -- Tree_Read is used. Tree_Read includes all necessary initialization. 155 156 procedure Tree_Write; 157 -- Writes out internal tables to current tree file using the relevant 158 -- Table.Tree_Write routines. 159 160 procedure Write_Char_Code (Code : Char_Code); 161 -- Procedure to write a character code value, used for debugging purposes 162 -- for writing character codes. If the character code is in the range 163 -- 16#20# .. 16#7E#, then the single graphic character corresponding to 164 -- the code is output. For any other codes in the range 16#00# .. 16#FF#, 165 -- the code is output as ["hh"] where hh is the two digit hex value for 166 -- the code. Codes greater than 16#FF# are output as ["hhhh"] where hhhh 167 -- is the four digit hex representation of the code value (high order 168 -- byte first). Hex letters are always in lower case. 169 170 procedure Write_String_Table_Entry (Id : String_Id); 171 -- Writes a string value with enclosing quotes to the current file using 172 -- routines in package Output. Does not write an end of line character. 173 -- This procedure is used for debug output purposes, and also for output 174 -- of strings specified by pragma Linker Option to the ali file. 7-bit 175 -- ASCII graphics (except for double quote) are output literally. 176 -- The double quote appears as two successive double quotes. 177 -- All other codes, are output as described for Write_Char_Code. For 178 -- example, the string created by folding "A" & ASCII.HT & "Hello" will 179 -- print as "A["09"]Hello". A No_String value prints simply as "no string" 180 -- without surrounding quote marks. 181 182private 183 pragma Inline (End_String); 184 pragma Inline (String_Length); 185 186end Stringt; 187