gcc/gcov-io.h

   1 /* Machine-independent I/O routines for gcov.
   2    Copyright (C) 1996, 1997, 1998, 2000 Free Software Foundation, Inc.
   3    Contributed by Bob Manson <manson@cygnus.com>.
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 2, or (at your option) any later
  10 version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING.  If not, write to the Free
  19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
  20 02111-1307, USA.  */
  21
  22 #ifndef GCC_GCOV_IO_H
  23 #define GCC_GCOV_IO_H
  24 #include <stdio.h>
  25 #include <sys/types.h>
  26
  27 static int __fetch_long PARAMS ((long *, char *, size_t))
  28         ATTRIBUTE_UNUSED;
  29 static int __read_long  PARAMS ((long *, FILE *, size_t))
  30         ATTRIBUTE_UNUSED;
  31 static int __write_long PARAMS ((long, FILE *, size_t))
  32         ATTRIBUTE_UNUSED;
  33 static int __fetch_gcov_type PARAMS ((gcov_type *, char *, size_t))
  34         ATTRIBUTE_UNUSED;
  35 static int __store_gcov_type PARAMS ((gcov_type, char *, size_t))
  36         ATTRIBUTE_UNUSED;
  37 static int __read_gcov_type  PARAMS ((gcov_type *, FILE *, size_t))
  38         ATTRIBUTE_UNUSED;
  39 static int __write_gcov_type PARAMS ((gcov_type, FILE *, size_t))
  40         ATTRIBUTE_UNUSED;
  41 static int __write_gcov_string PARAMS ((const char *, size_t, FILE*, long))
  42         ATTRIBUTE_UNUSED;
  43 static int __read_gcov_string PARAMS ((char *, size_t, FILE*, long))
  44         ATTRIBUTE_UNUSED;
  45
  46 /* These routines only work for signed values.  */
  47
  48 /* Store a portable representation of VALUE in DEST using BYTES*8-1 bits.
  49    Return a non-zero value if VALUE requires more than BYTES*8-1 bits
  50    to store.  */
  51
  52 static int
  53 __store_gcov_type (value, dest, bytes)
  54      gcov_type value;
  55      char *dest;
  56      size_t bytes;
  57 {
  58   int upper_bit = (value < 0 ? 128 : 0);
  59   size_t i;
  60
  61   if (value < 0)
  62     {
  63       gcov_type oldvalue = value;
  64       value = -value;
  65       if (oldvalue != -value)
  66         return 1;
  67     }
  68
  69   for(i = 0 ; i < (sizeof (value) < bytes ? sizeof (value) : bytes) ; i++) {
  70     dest[i] = value & (i == (bytes - 1) ? 127 : 255);
  71     value = value / 256;
  72   }
  73
  74   if (value && value != -1)
  75     return 1;
  76
  77   for(; i < bytes ; i++)
  78     dest[i] = 0;
  79   dest[bytes - 1] |= upper_bit;
  80   return 0;
  81 }
  82
  83 /* Retrieve a quantity containing BYTES*8-1 bits from SOURCE and store
  84    the result in DEST. Returns a non-zero value if the value in SOURCE
  85    will not fit in DEST.  */
  86
  87 static int
  88 __fetch_gcov_type (dest, source, bytes)
  89      gcov_type *dest;
  90      char *source;
  91      size_t bytes;
  92 {
  93   gcov_type value = 0;
  94   int i;
  95
  96   for (i = bytes - 1; (size_t) i > (sizeof (*dest) - 1); i--)
  97     if (source[i] & ((size_t) i == (bytes - 1) ? 127 : 255 ))
  98       return 1;
  99
 100   for (; i >= 0; i--)
 101     value = value * 256 + (source[i] & ((size_t)i == (bytes - 1) ? 127 : 255));
 102
 103   if ((source[bytes - 1] & 128) && (value > 0))
 104     value = - value;
 105
 106   *dest = value;
 107   return 0;
 108 }
 109
 110 static int
 111 __fetch_long (dest, source, bytes)
 112      long *dest;
 113      char *source;
 114      size_t bytes;
 115 {
 116   long value = 0;
 117   int i;
 118
 119   for (i = bytes - 1; (size_t) i > (sizeof (*dest) - 1); i--)
 120     if (source[i] & ((size_t) i == (bytes - 1) ? 127 : 255 ))
 121       return 1;
 122
 123   for (; i >= 0; i--)
 124     value = value * 256 + (source[i] & ((size_t)i == (bytes - 1) ? 127 : 255));
 125
 126   if ((source[bytes - 1] & 128) && (value > 0))
 127     value = - value;
 128
 129   *dest = value;
 130   return 0;
 131 }
 132
 133 /* Write a BYTES*8-bit quantity to FILE, portably. Returns a non-zero
 134    value if the write fails, or if VALUE can't be stored in BYTES*8
 135    bits.
 136
 137    Note that VALUE may not actually be large enough to hold BYTES*8
 138    bits, but BYTES characters will be written anyway.
 139
 140    BYTES may be a maximum of 10.  */
 141
 142 static int
 143 __write_gcov_type (value, file, bytes)
 144      gcov_type value;
 145      FILE *file;
 146      size_t bytes;
 147 {
 148   char c[10];
 149
 150   if (bytes > 10 || __store_gcov_type (value, c, bytes))
 151     return 1;
 152   else
 153     return fwrite(c, 1, bytes, file) != bytes;
 154 }
 155
 156 static int
 157 __write_long (value, file, bytes)
 158      long value;
 159      FILE *file;
 160      size_t bytes;
 161 {
 162   char c[10];
 163
 164   if (bytes > 10 || __store_gcov_type ((gcov_type)value, c, bytes))
 165     return 1;
 166   else
 167     return fwrite(c, 1, bytes, file) != bytes;
 168 }
 169
 170 /* Read a quantity containing BYTES bytes from FILE, portably. Return
 171    a non-zero value if the read fails or if the value will not fit
 172    in DEST.
 173
 174    Note that DEST may not be large enough to hold all of the requested
 175    data, but the function will read BYTES characters anyway.
 176
 177    BYTES may be a maximum of 10.  */
 178
 179 static int
 180 __read_gcov_type (dest, file, bytes)
 181      gcov_type *dest;
 182      FILE *file;
 183      size_t bytes;
 184 {
 185   char c[10];
 186
 187   if (bytes > 10 || fread(c, 1, bytes, file) != bytes)
 188     return 1;
 189   else
 190     return __fetch_gcov_type (dest, c, bytes);
 191 }
 192
 193 static int
 194 __read_long (dest, file, bytes)
 195      long *dest;
 196      FILE *file;
 197      size_t bytes;
 198 {
 199   char c[10];
 200
 201   if (bytes > 10 || fread(c, 1, bytes, file) != bytes)
 202     return 1;
 203   else
 204     return __fetch_long (dest, c, bytes);
 205 }
 206
 207
 208 /* Writes string in gcov format.  */
 209
 210 static int
 211 __write_gcov_string (string, length, file, delim)
 212      const char *string;
 213      size_t length;
 214      FILE *file;
 215      long delim;
 216 {
 217   size_t temp = length + 1;
 218
 219   /* delimiter */
 220   if (__write_long (delim, file, 4) != 0)
 221     return 1;
 222
 223   if (__write_long (length, file, 4) != 0)
 224     return 1;
 225
 226   if (fwrite (string, temp, 1, file) != 1)
 227     return 1;
 228
 229   temp &= 3;
 230
 231   if (temp)
 232     {
 233       char c[4];
 234
 235       c[0] = c[1] = c[2] = c[3] = 0;
 236
 237       if (fwrite (c, sizeof (char), 4 - temp, file) != 4 - temp)
 238         return 1;
 239     }
 240
 241   if (__write_long (delim, file, 4) != 0)
 242     return 1;
 243
 244   return 0;
 245 }
 246
 247 /* Reads string in gcov format.  */
 248
 249
 250 static int
 251 __read_gcov_string (string, max_length, file, delim)
 252      char *string;
 253      size_t max_length;
 254      FILE *file;
 255      long delim;
 256 {
 257   long delim_from_file;
 258   long length;
 259   long read_length;
 260   long tmp;
 261
 262   if (__read_long (&delim_from_file, file, 4) != 0)
 263     return 1;
 264
 265   if (delim_from_file != delim)
 266     return 1;
 267
 268   if (__read_long (&length, file, 4) != 0)
 269     return 1;
 270
 271   if (length > (long) max_length)
 272     read_length = max_length;
 273   else
 274     read_length = length;
 275
 276   tmp = (((length + 1) - 1) / 4 + 1) * 4;
 277   /* This is the size occupied by the string in the file */
 278
 279   if (fread (string, read_length, 1, file) != 1)
 280     return 1;
 281
 282   string[read_length] = 0;
 283
 284   if (fseek (file, tmp - read_length, SEEK_CUR) < 0)
 285     return 1;
 286
 287   if (__read_long (&delim_from_file, file, 4) != 0)
 288     return 1;
 289
 290   if (delim_from_file != delim)
 291     return 1;
 292
 293   return 0;
 294 }
 295
 296
 297 #endif /* ! GCC_GCOV_IO_H */