| 1 | /* sb.h - header file for string buffer manipulation routines |
| 2 | Copyright 1994, 1995, 2000, 2003, 2006 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 | /* String blocks |
| 29 | |
| 30 | I had a couple of choices when deciding upon this data structure. |
| 31 | gas uses null terminated strings for all its internal work. This |
| 32 | often means that parts of the program that want to examine |
| 33 | substrings have to manipulate the data in the string to do the |
| 34 | right thing (a common operation is to single out a bit of text by |
| 35 | saving away the character after it, nulling it out, operating on |
| 36 | the substring and then replacing the character which was under the |
| 37 | null). This is a pain and I remember a load of problems that I had with |
| 38 | code in gas which almost got this right. Also, it's harder to grow and |
| 39 | allocate null terminated strings efficiently. |
| 40 | |
| 41 | Obstacks provide all the functionality needed, but are too |
| 42 | complicated, hence the sb. |
| 43 | |
| 44 | An sb is allocated by the caller, and is initialized to point to an |
| 45 | sb_element. sb_elements are kept on a free lists, and used when |
| 46 | needed, replaced onto the free list when unused. */ |
| 47 | |
| 48 | #define sb_max_power_two 30 /* Don't allow strings more than |
| 49 | 2^sb_max_power_two long. */ |
| 50 | |
| 51 | typedef struct sb |
| 52 | { |
| 53 | char *ptr; /* Points to the current block. */ |
| 54 | int len; /* How much is used. */ |
| 55 | int pot; /* The maximum length is 1<<pot. */ |
| 56 | struct le *item; |
| 57 | } |
| 58 | sb; |
| 59 | |
| 60 | /* Structure of the free list object of a string block. */ |
| 61 | |
| 62 | typedef struct le |
| 63 | { |
| 64 | struct le *next; |
| 65 | int size; |
| 66 | char data[1]; |
| 67 | } |
| 68 | sb_element; |
| 69 | |
| 70 | extern void sb_new (sb *); |
| 71 | extern void sb_kill (sb *); |
| 72 | extern void sb_add_sb (sb *, sb *); |
| 73 | extern void sb_scrub_and_add_sb (sb *, sb *); |
| 74 | extern void sb_reset (sb *); |
| 75 | extern void sb_add_char (sb *, int); |
| 76 | extern void sb_add_string (sb *, const char *); |
| 77 | extern void sb_add_buffer (sb *, const char *, int); |
| 78 | extern char *sb_terminate (sb *); |
| 79 | extern int sb_skip_white (int, sb *); |
| 80 | extern int sb_skip_comma (int, sb *); |
| 81 | |
| 82 | /* Actually in input-scrub.c. */ |
| 83 | extern void input_scrub_include_sb (sb *, char *, int); |
| 84 | |
| 85 | #endif /* SB_H */ |