elf/dl-misc.c

   1 /* Miscellaneous support functions for dynamic linker
   2    Copyright (C) 1997, 1998, 1999 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Library General Public License as
   7    published by the Free Software Foundation; either version 2 of the
   8    License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Library General Public License for more details.
  14
  15    You should have received a copy of the GNU Library General Public
  16    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  17    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  18    Boston, MA 02111-1307, USA.  */
  19
  20 #include <assert.h>
  21 #include <fcntl.h>
  22 #include <unistd.h>
  23 #include <stdarg.h>
  24 #include <string.h>
  25 #include <unistd.h>
  26 #include <sys/mman.h>
  27 #include <sys/stat.h>
  28 #include <stdio-common/_itoa.h>
  29
  30 #ifndef MAP_ANON
  31 /* This is the only dl-sysdep.c function that is actually needed at run-time
  32    by _dl_map_object.  */
  33
  34 int
  35 _dl_sysdep_open_zero_fill (void)
  36 {
  37   return __open ("/dev/zero", O_RDONLY);
  38 }
  39 #endif
  40
  41 /* Read the whole contents of FILE into new mmap'd space with given
  42    protections.  *SIZEP gets the size of the file.  */
  43
  44 void *
  45 _dl_sysdep_read_whole_file (const char *file, size_t *sizep, int prot)
  46 {
  47   void *result;
  48   struct stat st;
  49   int fd = __open (file, O_RDONLY);
  50   if (fd < 0)
  51     return NULL;
  52   if (__fxstat (_STAT_VER, fd, &st) < 0
  53       /* No need to map the file if it is empty.  */
  54       || st.st_size == 0)
  55     result = NULL;
  56   else
  57     {
  58       /* Map a copy of the file contents.  */
  59       result = __mmap (0, st.st_size, prot,
  60 #ifdef MAP_COPY
  61                        MAP_COPY
  62 #else
  63                        MAP_PRIVATE
  64 #endif
  65 #ifdef MAP_FILE
  66                        | MAP_FILE
  67 #endif
  68                        , fd, 0);
  69       if (result == MAP_FAILED)
  70         result = NULL;
  71       else
  72         *sizep = st.st_size;
  73     }
  74   __close (fd);
  75   return result;
  76 }
  77
  78
  79 /* Descriptor to write debug messages to.  */
  80 int _dl_debug_fd = 2;
  81
  82
  83 void
  84 _dl_sysdep_output (int fd, const char *msg, ...)
  85 {
  86   va_list ap;
  87
  88   va_start (ap, msg);
  89   do
  90     {
  91       size_t len = strlen (msg);
  92       __libc_write (fd, msg, len);
  93       msg = va_arg (ap, const char *);
  94     }
  95   while (msg != NULL);
  96   va_end (ap);
  97 }
  98
  99
 100 void
 101 _dl_debug_message (int new_line, const char *msg, ...)
 102 {
 103   /* We print the strings we get passed one after the other but start all
 104      lines using the current PID.  */
 105   int pid = 0;
 106   va_list ap;
 107
 108   va_start (ap, msg);
 109   do
 110     if (msg[0] == '\0')
 111       /* Get the next argument.  */
 112       msg = va_arg (ap, const char *);
 113     else
 114       {
 115         const char *endp;
 116
 117         /* We actually will print something in this line.  So print the
 118            PID now if needed.  */
 119         if (new_line)
 120           {
 121             char buf[7];
 122             char *p;
 123             if (pid == 0)
 124               pid = __getpid ();
 125             assert (pid >= 0 && pid < 100000);
 126             p = _itoa_word (pid, &buf[5], 10, 0);
 127             while (p > buf)
 128               *--p = '0';
 129             buf[5] = ':';
 130             buf[6] = '\t';
 131             __libc_write (_dl_debug_fd, buf, 7);
 132             new_line = 0;
 133           }
 134
 135         endp = msg + strcspn (msg, "\n");
 136         if (*endp == '\0')
 137           {
 138             __libc_write (_dl_debug_fd, msg, endp - msg);
 139             msg = va_arg (ap, const char *);
 140           }
 141         else
 142           {
 143             __libc_write (_dl_debug_fd, msg, endp - msg + 1);
 144             msg = endp + 1;
 145             new_line = 1;
 146           }
 147       }
 148   while (msg != NULL);
 149   va_end (ap);
 150 }