1/* sb.c - 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#include "config.h"
25#include <stdio.h>
26#ifdef HAVE_STDLIB_H
27#include <stdlib.h>
28#endif
29#ifdef HAVE_STRING_H
30#include <string.h>
31#else
32#include <strings.h>
33#endif
34#include "libiberty.h"
35#include "sb.h"
36#include "as.h"
37
38/* These routines are about manipulating strings.
39
40   They are managed in things called `sb's which is an abbreviation
41   for string buffers.  An sb has to be created, things can be glued
42   on to it, and at the end of it's life it should be freed.  The
43   contents should never be pointed at whilst it is still growing,
44   since it could be moved at any time
45
46   eg:
47   sb_new (&foo);
48   sb_grow... (&foo,...);
49   use foo->ptr[*];
50   sb_kill (&foo);  */
51
52static int dsize = 5;
53static void sb_check (sb *, int);
54
55/* Statistics of sb structures.  */
56static int string_count[sb_max_power_two];
57
58/* Free list of sb structures.  */
59static sb_list_vector free_list;
60
61/* Initializes an sb.  */
62
63static void
64sb_build (sb *ptr, int size)
65{
66  /* See if we can find one to allocate.  */
67  sb_element *e;
68
69  if (size > sb_max_power_two)
70    abort ();
71
72  e = free_list.size[size];
73  if (!e)
74    {
75      /* Nothing there, allocate one and stick into the free list.  */
76      e = (sb_element *) xmalloc (sizeof (sb_element) + (1 << size));
77      e->next = free_list.size[size];
78      e->size = 1 << size;
79      free_list.size[size] = e;
80      string_count[size]++;
81    }
82
83  /* Remove from free list.  */
84  free_list.size[size] = e->next;
85
86  /* Copy into callers world.  */
87  ptr->ptr = e->data;
88  ptr->pot = size;
89  ptr->len = 0;
90  ptr->item = e;
91}
92
93void
94sb_new (sb *ptr)
95{
96  sb_build (ptr, dsize);
97}
98
99/* Deallocate the sb at ptr.  */
100
101void
102sb_kill (sb *ptr)
103{
104  /* Return item to free list.  */
105  ptr->item->next = free_list.size[ptr->pot];
106  free_list.size[ptr->pot] = ptr->item;
107}
108
109/* Add the sb at s to the end of the sb at ptr.  */
110
111void
112sb_add_sb (sb *ptr, sb *s)
113{
114  sb_check (ptr, s->len);
115  memcpy (ptr->ptr + ptr->len, s->ptr, s->len);
116  ptr->len += s->len;
117}
118
119/* Helper for sb_scrub_and_add_sb.  */
120
121static sb *sb_to_scrub;
122static char *scrub_position;
123static int
124scrub_from_sb (char *buf, int buflen)
125{
126  int copy;
127  copy = sb_to_scrub->len - (scrub_position - sb_to_scrub->ptr);
128  if (copy > buflen)
129    copy = buflen;
130  memcpy (buf, scrub_position, copy);
131  scrub_position += copy;
132  return copy;
133}
134
135/* Run the sb at s through do_scrub_chars and add the result to the sb
136   at ptr.  */
137
138void
139sb_scrub_and_add_sb (sb *ptr, sb *s)
140{
141  sb_to_scrub = s;
142  scrub_position = s->ptr;
143
144  sb_check (ptr, s->len);
145  ptr->len += do_scrub_chars (scrub_from_sb, ptr->ptr + ptr->len, s->len);
146
147  sb_to_scrub = 0;
148  scrub_position = 0;
149}
150
151/* Make sure that the sb at ptr has room for another len characters,
152   and grow it if it doesn't.  */
153
154static void
155sb_check (sb *ptr, int len)
156{
157  if (ptr->len + len >= 1 << ptr->pot)
158    {
159      sb tmp;
160      int pot = ptr->pot;
161
162      while (ptr->len + len >= 1 << pot)
163	pot++;
164      sb_build (&tmp, pot);
165      sb_add_sb (&tmp, ptr);
166      sb_kill (ptr);
167      *ptr = tmp;
168    }
169}
170
171/* Make the sb at ptr point back to the beginning.  */
172
173void
174sb_reset (sb *ptr)
175{
176  ptr->len = 0;
177}
178
179/* Add character c to the end of the sb at ptr.  */
180
181void
182sb_add_char (sb *ptr, int c)
183{
184  sb_check (ptr, 1);
185  ptr->ptr[ptr->len++] = c;
186}
187
188/* Add null terminated string s to the end of sb at ptr.  */
189
190void
191sb_add_string (sb *ptr, const char *s)
192{
193  int len = strlen (s);
194  sb_check (ptr, len);
195  memcpy (ptr->ptr + ptr->len, s, len);
196  ptr->len += len;
197}
198
199/* Add string at s of length len to sb at ptr */
200
201void
202sb_add_buffer (sb *ptr, const char *s, int len)
203{
204  sb_check (ptr, len);
205  memcpy (ptr->ptr + ptr->len, s, len);
206  ptr->len += len;
207}
208
209/* Like sb_name, but don't include the null byte in the string.  */
210
211char *
212sb_terminate (sb *in)
213{
214  sb_add_char (in, 0);
215  --in->len;
216  return in->ptr;
217}
218
219/* Start at the index idx into the string in sb at ptr and skip
220   whitespace. return the index of the first non whitespace character.  */
221
222int
223sb_skip_white (int idx, sb *ptr)
224{
225  while (idx < ptr->len
226	 && (ptr->ptr[idx] == ' '
227	     || ptr->ptr[idx] == '\t'))
228    idx++;
229  return idx;
230}
231
232/* Start at the index idx into the sb at ptr. skips whitespace,
233   a comma and any following whitespace. returns the index of the
234   next character.  */
235
236int
237sb_skip_comma (int idx, sb *ptr)
238{
239  while (idx < ptr->len
240	 && (ptr->ptr[idx] == ' '
241	     || ptr->ptr[idx] == '\t'))
242    idx++;
243
244  if (idx < ptr->len
245      && ptr->ptr[idx] == ',')
246    idx++;
247
248  while (idx < ptr->len
249	 && (ptr->ptr[idx] == ' '
250	     || ptr->ptr[idx] == '\t'))
251    idx++;
252
253  return idx;
254}
255