1 /* sb.h - header file for string buffer manipulation routines 2 Copyright 1994, 1995, 2000, 2003 Free Software Foundation, Inc. 3 4 Written by Steve and Judy Chamberlain of Cygnus Support, 5 sac@cygnus.com 6 7 This file is part of GAS, the GNU Assembler. 8 9 GAS is free software; you can redistribute it and/or modify 10 it under the terms of the GNU General Public License as published by 11 the Free Software Foundation; either version 2, or (at your option) 12 any later version. 13 14 GAS is distributed in the hope that it will be useful, 15 but WITHOUT ANY WARRANTY; without even the implied warranty of 16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 GNU General Public License for more details. 18 19 You should have received a copy of the GNU General Public License 20 along with GAS; see the file COPYING. If not, write to the Free 21 Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA 22 02110-1301, USA. */ 23 24 #ifndef SB_H 25 26 #define SB_H 27 28 #include <stdio.h> 29 #include "ansidecl.h" 30 31 /* String blocks 32 33 I had a couple of choices when deciding upon this data structure. 34 gas uses null terminated strings for all its internal work. This 35 often means that parts of the program that want to examine 36 substrings have to manipulate the data in the string to do the 37 right thing (a common operation is to single out a bit of text by 38 saving away the character after it, nulling it out, operating on 39 the substring and then replacing the character which was under the 40 null). This is a pain and I remember a load of problems that I had with 41 code in gas which almost got this right. Also, it's harder to grow and 42 allocate null terminated strings efficiently. 43 44 Obstacks provide all the functionality needed, but are too 45 complicated, hence the sb. 46 47 An sb is allocated by the caller, and is initialized to point to an 48 sb_element. sb_elements are kept on a free lists, and used when 49 needed, replaced onto the free list when unused. */ 50 51 #define sb_max_power_two 30 /* Don't allow strings more than 52 2^sb_max_power_two long. */ 53 54 typedef struct sb 55 { 56 char *ptr; /* Points to the current block. */ 57 int len; /* How much is used. */ 58 int pot; /* The maximum length is 1<<pot. */ 59 struct le *item; 60 } 61 sb; 62 63 /* Structure of the free list object of a string block. */ 64 65 typedef struct le 66 { 67 struct le *next; 68 int size; 69 char data[1]; 70 } 71 sb_element; 72 73 /* The free list. */ 74 75 typedef struct 76 { 77 sb_element *size[sb_max_power_two]; 78 } 79 sb_list_vector; 80 81 extern void sb_new (sb *); 82 extern void sb_kill (sb *); 83 extern void sb_add_sb (sb *, sb *); 84 extern void sb_scrub_and_add_sb (sb *, sb *); 85 extern void sb_reset (sb *); 86 extern void sb_add_char (sb *, int); 87 extern void sb_add_string (sb *, const char *); 88 extern void sb_add_buffer (sb *, const char *, int); 89 extern char *sb_terminate (sb *); 90 extern int sb_skip_white (int, sb *); 91 extern int sb_skip_comma (int, sb *); 92 93 /* Actually in input-scrub.c. */ 94 extern void input_scrub_include_sb (sb *, char *, int); 95 96 #endif /* SB_H */ 97