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[binutils.git] / gas / sb.h
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1 /* sb.h - header file for string buffer manipulation routines
2 Copyright 1994, 1995, 2000, 2003 Free Software Foundation, Inc.
4 Written by Steve and Judy Chamberlain of Cygnus Support,
5 sac@cygnus.com
7 This file is part of GAS, the GNU Assembler.
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.
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.
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. */
24 #ifndef SB_H
26 #define SB_H
28 #include <stdio.h>
29 #include "ansidecl.h"
31 /* String blocks
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.
44 Obstacks provide all the functionality needed, but are too
45 complicated, hence the sb.
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. */
51 #define sb_max_power_two 30 /* Don't allow strings more than
52 2^sb_max_power_two long. */
54 typedef struct sb
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;
61 sb;
63 /* Structure of the free list object of a string block. */
65 typedef struct le
67 struct le *next;
68 int size;
69 char data[1];
71 sb_element;
73 /* The free list. */
75 typedef struct
77 sb_element *size[sb_max_power_two];
79 sb_list_vector;
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 *);
93 /* Actually in input-scrub.c. */
94 extern void input_scrub_include_sb (sb *, char *, int);
96 #endif /* SB_H */