gdb/gdbserver/utils.c

   1 /* General utility routines for the remote server for GDB.
   2    Copyright (C) 1986, 1989, 1993, 1995, 1996, 1997, 1999, 2000, 2002, 2003,
   3    2007, 2008, 2009 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "server.h"
  21 #include <stdio.h>
  22 #include <string.h>
  23 #include <stdlib.h>
  24 #if HAVE_ERRNO_H
  25 #include <errno.h>
  26 #endif
  27 #if HAVE_MALLOC_H
  28 #include <malloc.h>
  29 #endif
  30
  31 /* Generally useful subroutines used throughout the program.  */
  32
  33 static void malloc_failure (size_t size) ATTR_NORETURN;
  34
  35 static void
  36 malloc_failure (size_t size)
  37 {
  38   fprintf (stderr, "gdbserver: ran out of memory while trying to allocate %lu bytes\n",
  39            (unsigned long) size);
  40   exit (1);
  41 }
  42
  43 /* Allocate memory without fail.
  44    If malloc fails, this will print a message to stderr and exit.  */
  45
  46 void *
  47 xmalloc (size_t size)
  48 {
  49   void *newmem;
  50
  51   if (size == 0)
  52     size = 1;
  53   newmem = malloc (size);
  54   if (!newmem)
  55     malloc_failure (size);
  56
  57   return newmem;
  58 }
  59
  60 /* Allocate memory without fail and set it to zero.
  61    If malloc fails, this will print a message to stderr and exit.  */
  62
  63 void *
  64 xcalloc (size_t nelem, size_t elsize)
  65 {
  66   void *newmem;
  67
  68   if (nelem == 0 || elsize == 0)
  69     nelem = elsize = 1;
  70
  71   newmem = calloc (nelem, elsize);
  72   if (!newmem)
  73     malloc_failure (nelem * elsize);
  74
  75   return newmem;
  76 }
  77
  78 /* Copy a string into a memory buffer.
  79    If malloc fails, this will print a message to stderr and exit.  */
  80
  81 char *
  82 xstrdup (const char *s)
  83 {
  84   char *ret = strdup (s);
  85   if (ret == NULL)
  86     malloc_failure (strlen (s) + 1);
  87   return ret;
  88 }
  89
  90 /* Free a standard argv vector.  */
  91
  92 void
  93 freeargv (char **vector)
  94 {
  95   char **scan;
  96
  97   if (vector != NULL)
  98     {
  99       for (scan = vector; *scan != NULL; scan++)
 100         {
 101           free (*scan);
 102         }
 103       free (vector);
 104     }
 105 }
 106
 107 /* Print the system error message for errno, and also mention STRING
 108    as the file name for which the error was encountered.
 109    Then return to command level.  */
 110
 111 void
 112 perror_with_name (const char *string)
 113 {
 114   const char *err;
 115   char *combined;
 116
 117   err = strerror (errno);
 118   if (err == NULL)
 119     err = "unknown error";
 120
 121   combined = (char *) alloca (strlen (err) + strlen (string) + 3);
 122   strcpy (combined, string);
 123   strcat (combined, ": ");
 124   strcat (combined, err);
 125
 126   error ("%s.", combined);
 127 }
 128
 129 /* Print an error message and return to command level.
 130    STRING is the error message, used as a fprintf string,
 131    and ARG is passed as an argument to it.  */
 132
 133 void
 134 error (const char *string,...)
 135 {
 136   extern jmp_buf toplevel;
 137   va_list args;
 138   va_start (args, string);
 139   fflush (stdout);
 140   vfprintf (stderr, string, args);
 141   fprintf (stderr, "\n");
 142   longjmp (toplevel, 1);
 143 }
 144
 145 /* Print an error message and exit reporting failure.
 146    This is for a error that we cannot continue from.
 147    STRING and ARG are passed to fprintf.  */
 148
 149 /* VARARGS */
 150 void
 151 fatal (const char *string,...)
 152 {
 153   va_list args;
 154   va_start (args, string);
 155   fprintf (stderr, "gdbserver: ");
 156   vfprintf (stderr, string, args);
 157   fprintf (stderr, "\n");
 158   va_end (args);
 159   exit (1);
 160 }
 161
 162 /* VARARGS */
 163 void
 164 warning (const char *string,...)
 165 {
 166   va_list args;
 167   va_start (args, string);
 168   fprintf (stderr, "gdbserver: ");
 169   vfprintf (stderr, string, args);
 170   fprintf (stderr, "\n");
 171   va_end (args);
 172 }
 173
 174 /* Temporary storage using circular buffer.  */
 175 #define NUMCELLS 4
 176 #define CELLSIZE 50
 177
 178 /* Return the next entry in the circular buffer.  */
 179
 180 static char *
 181 get_cell (void)
 182 {
 183   static char buf[NUMCELLS][CELLSIZE];
 184   static int cell = 0;
 185   if (++cell >= NUMCELLS)
 186     cell = 0;
 187   return buf[cell];
 188 }
 189
 190 /* Stdarg wrapper around vsnprintf.
 191    SIZE is the size of the buffer pointed to by STR.  */
 192
 193 static int
 194 xsnprintf (char *str, size_t size, const char *format, ...)
 195 {
 196   va_list args;
 197   int ret;
 198
 199   va_start (args, format);
 200   ret = vsnprintf (str, size, format, args);
 201   va_end (args);
 202
 203   return ret;
 204 }
 205
 206 /* Convert a CORE_ADDR into a HEX string, like %lx.
 207    The result is stored in a circular static buffer, NUMCELLS deep.  */
 208
 209 char *
 210 paddress (CORE_ADDR addr)
 211 {
 212   char *str = get_cell ();
 213   xsnprintf (str, CELLSIZE, "%lx", (long) addr);
 214   return str;
 215 }