libgcc/libgcov-driver-system.c

   1 /* Routines required for instrumenting a program.  */
   2 /* Compile this one with gcc.  */
   3 /* Copyright (C) 1989-2017 Free Software Foundation, Inc.
   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 3, 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 Under Section 7 of GPL version 3, you are granted additional
  18 permissions described in the GCC Runtime Library Exception, version
  19 3.1, as published by the Free Software Foundation.
  20
  21 You should have received a copy of the GNU General Public License and
  22 a copy of the GCC Runtime Library Exception along with this program;
  23 see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  24 <http://www.gnu.org/licenses/>.  */
  25
  26 #if !IN_GCOV_TOOL
  27 /* Configured via the GCOV_ERROR_FILE environment variable;
  28    it will either be stderr, or a file of the user's choosing.
  29    Non-static to prevent multiple gcov-aware shared objects from
  30    instantiating their own copies. */
  31 FILE *__gcov_error_file = NULL;
  32 #endif
  33
  34 /* A utility function to populate the __gcov_error_file pointer.
  35    This should NOT be called outside of the gcov system driver code. */
  36
  37 static FILE *
  38 get_gcov_error_file (void)
  39 {
  40 #if IN_GCOV_TOOL
  41   return stderr;
  42 #else
  43   if (!__gcov_error_file)
  44     {
  45       const char *gcov_error_filename = getenv ("GCOV_ERROR_FILE");
  46
  47       if (gcov_error_filename)
  48         __gcov_error_file = fopen (gcov_error_filename, "a");
  49       if (!__gcov_error_file)
  50         __gcov_error_file = stderr;
  51     }
  52   return __gcov_error_file;
  53 #endif
  54 }
  55
  56 /* A utility function for outputting errors.  */
  57
  58 static int __attribute__((format(printf, 1, 2)))
  59 gcov_error (const char *fmt, ...)
  60 {
  61   int ret;
  62   va_list argp;
  63
  64   va_start (argp, fmt);
  65   ret = vfprintf (get_gcov_error_file (), fmt, argp);
  66   va_end (argp);
  67   return ret;
  68 }
  69
  70 #if !IN_GCOV_TOOL
  71 static void
  72 gcov_error_exit (void)
  73 {
  74   if (__gcov_error_file && __gcov_error_file != stderr)
  75     {
  76       fclose (__gcov_error_file);
  77       __gcov_error_file = NULL;
  78     }
  79 }
  80 #endif
  81
  82 /* Make sure path component of the given FILENAME exists, create
  83    missing directories. FILENAME must be writable.
  84    Returns zero on success, or -1 if an error occurred.  */
  85
  86 static int
  87 create_file_directory (char *filename)
  88 {
  89 #if !defined(TARGET_POSIX_IO) && !defined(_WIN32)
  90   (void) filename;
  91   return -1;
  92 #else
  93   char *s;
  94
  95   s = filename;
  96
  97   if (HAS_DRIVE_SPEC(s))
  98     s += 2;
  99   if (IS_DIR_SEPARATOR(*s))
 100     ++s;
 101   for (; *s != '\0'; s++)
 102     if (IS_DIR_SEPARATOR(*s))
 103       {
 104         char sep = *s;
 105         *s  = '\0';
 106
 107         /* Try to make directory if it doesn't already exist.  */
 108         if (access (filename, F_OK) == -1
 109 #ifdef TARGET_POSIX_IO
 110             && mkdir (filename, 0755) == -1
 111 #else
 112 #ifdef mkdir
 113 #undef mkdir
 114 #endif
 115             && mkdir (filename) == -1
 116 #endif
 117             /* The directory might have been made by another process.  */
 118             && errno != EEXIST)
 119           {
 120             gcov_error ("profiling:%s:Cannot create directory\n", filename);
 121             *s = sep;
 122             return -1;
 123           };
 124
 125         *s = sep;
 126       };
 127   return 0;
 128 #endif
 129 }
 130
 131 static void
 132 allocate_filename_struct (struct gcov_filename *gf)
 133 {
 134   const char *gcov_prefix;
 135   size_t prefix_length;
 136   int strip = 0;
 137
 138   {
 139     /* Check if the level of dirs to strip off specified. */
 140     char *tmp = getenv("GCOV_PREFIX_STRIP");
 141     if (tmp)
 142       {
 143         strip = atoi (tmp);
 144         /* Do not consider negative values. */
 145         if (strip < 0)
 146           strip = 0;
 147       }
 148   }
 149   gf->strip = strip;
 150
 151   /* Get file name relocation prefix.  Non-absolute values are ignored. */
 152   gcov_prefix = getenv("GCOV_PREFIX");
 153   prefix_length = gcov_prefix ? strlen (gcov_prefix) : 0;
 154
 155   /* Remove an unnecessary trailing '/' */
 156   if (prefix_length && IS_DIR_SEPARATOR (gcov_prefix[prefix_length - 1]))
 157     prefix_length--;
 158
 159   /* If no prefix was specified and a prefix stip, then we assume
 160      relative.  */
 161   if (!prefix_length && gf->strip)
 162     {
 163       gcov_prefix = ".";
 164       prefix_length = 1;
 165     }
 166   gf->prefix = prefix_length;
 167
 168   /* Allocate and initialize the filename scratch space.  */
 169   gf->filename = (char *) xmalloc (gf->max_length + prefix_length + 2);
 170   if (prefix_length)
 171     memcpy (gf->filename, gcov_prefix, prefix_length);
 172 }
 173
 174 /* Open a gcda file specified by GI_FILENAME.
 175    Return -1 on error.  Return 0 on success.  */
 176
 177 static int
 178 gcov_exit_open_gcda_file (struct gcov_info *gi_ptr,
 179                           struct gcov_filename *gf)
 180 {
 181   const char *fname = gi_ptr->filename;
 182   char *dst = gf->filename + gf->prefix;
 183
 184   fname = gi_ptr->filename;
 185
 186   /* Build relocated filename, stripping off leading
 187      directories from the initial filename if requested. */
 188   if (gf->strip > 0)
 189     {
 190       const char *probe = fname;
 191       int level;
 192
 193       /* Remove a leading separator, without counting it.  */
 194       if (IS_DIR_SEPARATOR (*probe))
 195         probe++;
 196
 197       /* Skip selected directory levels.  If we fall off the end, we
 198          keep the final part.  */
 199       for (level = gf->strip; *probe && level; probe++)
 200         if (IS_DIR_SEPARATOR (*probe))
 201           {
 202             fname = probe;
 203             level--;
 204           }
 205     }
 206
 207   /* Update complete filename with stripped original. */
 208   if (gf->prefix)
 209     {
 210       /* Avoid to add multiple drive letters into combined path.  */
 211       if (HAS_DRIVE_SPEC(fname))
 212         fname += 2;
 213
 214       if (!IS_DIR_SEPARATOR (*fname))
 215         *dst++ = '/';
 216     }
 217   strcpy (dst, fname);
 218
 219   if (!gcov_open (gf->filename))
 220     {
 221       /* Open failed likely due to missed directory.
 222          Create directory and retry to open file. */
 223       if (create_file_directory (gf->filename))
 224         {
 225           fprintf (stderr, "profiling:%s:Skip\n", gf->filename);
 226           return -1;
 227         }
 228       if (!gcov_open (gf->filename))
 229         {
 230           fprintf (stderr, "profiling:%s:Cannot open\n", gf->filename);
 231           return -1;
 232         }
 233     }
 234
 235   return 0;
 236 }