gas/sb.c

   1 /* sb.c - string buffer manipulation routines
   2    Copyright (C) 1994, 1995 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 PARAMS ((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 (ptr, size)
  69      sb *ptr;
  70      int size;
  71 {
  72   /* see if we can find one to allocate */
  73   sb_element *e;
  74
  75   if (size > sb_max_power_two)
  76     abort ();
  77
  78   e = free_list.size[size];
  79   if (!e)
  80     {
  81       /* nothing there, allocate one and stick into the free list */
  82       e = (sb_element *) xmalloc (sizeof (sb_element) + (1 << size));
  83       e->next = free_list.size[size];
  84       e->size = 1 << size;
  85       free_list.size[size] = e;
  86       string_count[size]++;
  87     }
  88
  89   /* remove from free list */
  90
  91   free_list.size[size] = e->next;
  92
  93   /* copy into callers world */
  94   ptr->ptr = e->data;
  95   ptr->pot = size;
  96   ptr->len = 0;
  97   ptr->item = e;
  98 }
  99
 100
 101 void
 102 sb_new (ptr)
 103      sb *ptr;
 104 {
 105   sb_build (ptr, dsize);
 106 }
 107
 108 /* deallocate the sb at ptr */
 109
 110 void
 111 sb_kill (ptr)
 112      sb *ptr;
 113 {
 114   /* return item to free list */
 115   ptr->item->next = free_list.size[ptr->pot];
 116   free_list.size[ptr->pot] = ptr->item;
 117 }
 118
 119 /* add the sb at s to the end of the sb at ptr */
 120
 121 void
 122 sb_add_sb (ptr, s)
 123      sb *ptr;
 124      sb *s;
 125 {
 126   sb_check (ptr, s->len);
 127   memcpy (ptr->ptr + ptr->len, s->ptr, s->len);
 128   ptr->len += s->len;
 129 }
 130
 131 /* make sure that the sb at ptr has room for another len characters,
 132    and grow it if it doesn't. */
 133
 134 static void
 135 sb_check (ptr, len)
 136      sb *ptr;
 137      int len;
 138 {
 139   if (ptr->len + len >= 1 << ptr->pot)
 140     {
 141       sb tmp;
 142       int pot = ptr->pot;
 143       while (ptr->len + len >= 1 << pot)
 144         pot++;
 145       sb_build (&tmp, pot);
 146       sb_add_sb (&tmp, ptr);
 147       sb_kill (ptr);
 148       *ptr = tmp;
 149     }
 150 }
 151
 152 /* make the sb at ptr point back to the beginning.  */
 153
 154 void
 155 sb_reset (ptr)
 156      sb *ptr;
 157 {
 158   ptr->len = 0;
 159 }
 160
 161 /* add character c to the end of the sb at ptr. */
 162
 163 void
 164 sb_add_char (ptr, c)
 165      sb *ptr;
 166      int c;
 167 {
 168   sb_check (ptr, 1);
 169   ptr->ptr[ptr->len++] = c;
 170 }
 171
 172 /* add null terminated string s to the end of sb at ptr. */
 173
 174 void
 175 sb_add_string (ptr, s)
 176      sb *ptr;
 177      const char *s;
 178 {
 179   int len = strlen (s);
 180   sb_check (ptr, len);
 181   memcpy (ptr->ptr + ptr->len, s, len);
 182   ptr->len += len;
 183 }
 184
 185 /* add string at s of length len to sb at ptr */
 186
 187 void
 188 sb_add_buffer (ptr, s, len)
 189      sb *ptr;
 190      const char *s;
 191      int len;
 192 {
 193   sb_check (ptr, len);
 194   memcpy (ptr->ptr + ptr->len, s, len);
 195   ptr->len += len;
 196 }
 197
 198 /* print the sb at ptr to the output file */
 199
 200 void
 201 sb_print (outfile, ptr)
 202      FILE *outfile;
 203      sb *ptr;
 204 {
 205   int i;
 206   int nc = 0;
 207
 208   for (i = 0; i < ptr->len; i++)
 209     {
 210       if (nc)
 211         {
 212           fprintf (outfile, ",");
 213         }
 214       fprintf (outfile, "%d", ptr->ptr[i]);
 215       nc = 1;
 216     }
 217 }
 218
 219 void
 220 sb_print_at (outfile, idx, ptr)
 221      FILE *outfile;
 222      int idx;
 223      sb *ptr;
 224 {
 225   int i;
 226   for (i = idx; i < ptr->len; i++)
 227     putc (ptr->ptr[i], outfile);
 228 }
 229
 230 /* put a null at the end of the sb at in and return the start of the
 231    string, so that it can be used as an arg to printf %s. */
 232
 233 char *
 234 sb_name (in)
 235      sb *in;
 236 {
 237   /* stick a null on the end of the string */
 238   sb_add_char (in, 0);
 239   return in->ptr;
 240 }
 241
 242 /* like sb_name, but don't include the null byte in the string.  */
 243
 244 char *
 245 sb_terminate (in)
 246      sb *in;
 247 {
 248   sb_add_char (in, 0);
 249   --in->len;
 250   return in->ptr;
 251 }
 252
 253 /* start at the index idx into the string in sb at ptr and skip
 254    whitespace. return the index of the first non whitespace character */
 255
 256 int
 257 sb_skip_white (idx, ptr)
 258      int idx;
 259      sb *ptr;
 260 {
 261   while (idx < ptr->len
 262          && (ptr->ptr[idx] == ' '
 263              || ptr->ptr[idx] == '\t'))
 264     idx++;
 265   return idx;
 266 }
 267
 268 /* start at the index idx into the sb at ptr. skips whitespace,
 269    a comma and any following whitespace. returnes the index of the
 270    next character. */
 271
 272 int
 273 sb_skip_comma (idx, ptr)
 274      int idx;
 275      sb *ptr;
 276 {
 277   while (idx < ptr->len
 278          && (ptr->ptr[idx] == ' '
 279              || ptr->ptr[idx] == '\t'))
 280     idx++;
 281
 282   if (idx < ptr->len
 283       && ptr->ptr[idx] == ',')
 284     idx++;
 285
 286   while (idx < ptr->len
 287          && (ptr->ptr[idx] == ' '
 288              || ptr->ptr[idx] == '\t'))
 289     idx++;
 290
 291   return idx;
 292 }