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