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