gas/sb.c

   1 /* sb.c - string buffer manipulation routines
   2    Copyright 1994, 1995, 2000 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, 59 Temple Place - Suite 330, Boston, MA
  22    02111-1307, 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
  37 /* These routines are about manipulating strings.
  38
  39    They are managed in things called `sb's which is an abbreviation
  40    for string buffers.  An sb has to be created, things can be glued
  41    on to it, and at the end of it's life it should be freed.  The
  42    contents should never be pointed at whilst it is still growing,
  43    since it could be moved at any time
  44
  45    eg:
  46    sb_new (&foo);
  47    sb_grow... (&foo,...);
  48    use foo->ptr[*];
  49    sb_kill (&foo);
  50
  51 */
  52
  53 #define dsize 5
  54
  55 static void sb_check (sb *, int);
  56
  57 /* Statistics of sb structures.  */
  58
  59 int string_count[sb_max_power_two];
  60
  61 /* Free list of sb structures.  */
  62
  63 static sb_list_vector free_list;
  64
  65 /* initializes an sb.  */
  66
  67 void
  68 sb_build (sb *ptr, int size)
  69 {
  70   /* see if we can find one to allocate */
  71   sb_element *e;
  72
  73   if (size > sb_max_power_two)
  74     abort ();
  75
  76   e = free_list.size[size];
  77   if (!e)
  78     {
  79       /* nothing there, allocate one and stick into the free list */
  80       e = (sb_element *) xmalloc (sizeof (sb_element) + (1 << size));
  81       e->next = free_list.size[size];
  82       e->size = 1 << size;
  83       free_list.size[size] = e;
  84       string_count[size]++;
  85     }
  86
  87   /* remove from free list */
  88
  89   free_list.size[size] = e->next;
  90
  91   /* copy into callers world */
  92   ptr->ptr = e->data;
  93   ptr->pot = size;
  94   ptr->len = 0;
  95   ptr->item = e;
  96 }
  97
  98 void
  99 sb_new (sb *ptr)
 100 {
 101   sb_build (ptr, dsize);
 102 }
 103
 104 /* deallocate the sb at ptr */
 105
 106 void
 107 sb_kill (sb *ptr)
 108 {
 109   /* return item to free list */
 110   ptr->item->next = free_list.size[ptr->pot];
 111   free_list.size[ptr->pot] = ptr->item;
 112 }
 113
 114 /* add the sb at s to the end of the sb at ptr */
 115
 116 void
 117 sb_add_sb (sb *ptr, sb *s)
 118 {
 119   sb_check (ptr, s->len);
 120   memcpy (ptr->ptr + ptr->len, s->ptr, s->len);
 121   ptr->len += s->len;
 122 }
 123
 124 /* make sure that the sb at ptr has room for another len characters,
 125    and grow it if it doesn't.  */
 126
 127 static void
 128 sb_check (sb *ptr, int len)
 129 {
 130   if (ptr->len + len >= 1 << ptr->pot)
 131     {
 132       sb tmp;
 133       int pot = ptr->pot;
 134       while (ptr->len + len >= 1 << pot)
 135         pot++;
 136       sb_build (&tmp, pot);
 137       sb_add_sb (&tmp, ptr);
 138       sb_kill (ptr);
 139       *ptr = tmp;
 140     }
 141 }
 142
 143 /* make the sb at ptr point back to the beginning.  */
 144
 145 void
 146 sb_reset (sb *ptr)
 147 {
 148   ptr->len = 0;
 149 }
 150
 151 /* add character c to the end of the sb at ptr.  */
 152
 153 void
 154 sb_add_char (sb *ptr, int c)
 155 {
 156   sb_check (ptr, 1);
 157   ptr->ptr[ptr->len++] = c;
 158 }
 159
 160 /* add null terminated string s to the end of sb at ptr.  */
 161
 162 void
 163 sb_add_string (sb *ptr, const char *s)
 164 {
 165   int len = strlen (s);
 166   sb_check (ptr, len);
 167   memcpy (ptr->ptr + ptr->len, s, len);
 168   ptr->len += len;
 169 }
 170
 171 /* add string at s of length len to sb at ptr */
 172
 173 void
 174 sb_add_buffer (sb *ptr, const char *s, int len)
 175 {
 176   sb_check (ptr, len);
 177   memcpy (ptr->ptr + ptr->len, s, len);
 178   ptr->len += len;
 179 }
 180
 181 /* print the sb at ptr to the output file */
 182
 183 void
 184 sb_print (FILE *outfile, sb *ptr)
 185 {
 186   int i;
 187   int nc = 0;
 188
 189   for (i = 0; i < ptr->len; i++)
 190     {
 191       if (nc)
 192         {
 193           fprintf (outfile, ",");
 194         }
 195       fprintf (outfile, "%d", ptr->ptr[i]);
 196       nc = 1;
 197     }
 198 }
 199
 200 void
 201 sb_print_at (FILE *outfile, int idx, sb *ptr)
 202 {
 203   int i;
 204   for (i = idx; i < ptr->len; i++)
 205     putc (ptr->ptr[i], outfile);
 206 }
 207
 208 /* put a null at the end of the sb at in and return the start of the
 209    string, so that it can be used as an arg to printf %s.  */
 210
 211 char *
 212 sb_name (sb *in)
 213 {
 214   /* stick a null on the end of the string */
 215   sb_add_char (in, 0);
 216   return in->ptr;
 217 }
 218
 219 /* like sb_name, but don't include the null byte in the string.  */
 220
 221 char *
 222 sb_terminate (sb *in)
 223 {
 224   sb_add_char (in, 0);
 225   --in->len;
 226   return in->ptr;
 227 }
 228
 229 /* start at the index idx into the string in sb at ptr and skip
 230    whitespace. return the index of the first non whitespace character */
 231
 232 int
 233 sb_skip_white (int idx, sb *ptr)
 234 {
 235   while (idx < ptr->len
 236          && (ptr->ptr[idx] == ' '
 237              || ptr->ptr[idx] == '\t'))
 238     idx++;
 239   return idx;
 240 }
 241
 242 /* start at the index idx into the sb at ptr. skips whitespace,
 243    a comma and any following whitespace. returns the index of the
 244    next character.  */
 245
 246 int
 247 sb_skip_comma (int idx, sb *ptr)
 248 {
 249   while (idx < ptr->len
 250          && (ptr->ptr[idx] == ' '
 251              || ptr->ptr[idx] == '\t'))
 252     idx++;
 253
 254   if (idx < ptr->len
 255       && ptr->ptr[idx] == ',')
 256     idx++;
 257
 258   while (idx < ptr->len
 259          && (ptr->ptr[idx] == ' '
 260              || ptr->ptr[idx] == '\t'))
 261     idx++;
 262
 263   return idx;
 264 }