gdb/i386-cygwin-tdep.c

   1 /* Target-dependent code for Cygwin running on i386's, for GDB.
   2
   3    Copyright (C) 2003, 2007, 2008, 2009, 2010 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 "defs.h"
  21 #include "osabi.h"
  22 #include "gdb_string.h"
  23 #include "i386-tdep.h"
  24 #include "windows-tdep.h"
  25 #include "regset.h"
  26 #include "gdb_obstack.h"
  27 #include "xml-support.h"
  28 #include "gdbcore.h"
  29 #include "solib.h"
  30 #include "solib-target.h"
  31
  32 /* Core file support.  */
  33
  34 /* This vector maps GDB's idea of a register's number into an address
  35    in the windows exception context vector.  */
  36
  37 static int i386_windows_gregset_reg_offset[] =
  38 {
  39   176, /* eax */
  40   172, /* ecx */
  41   168, /* edx */
  42   164, /* ebx */
  43
  44   196, /* esp */
  45   180, /* ebp */
  46   160, /* esi */
  47   156, /* edi */
  48
  49   184, /* eip */
  50   192, /* eflags */
  51   188, /* cs */
  52   200, /* ss */
  53
  54   152, /* ds */
  55   148, /* es */
  56   144, /* fs */
  57   140, /* gs */
  58
  59   56, /* FloatSave.RegisterArea[0 * 10] */
  60   66, /* FloatSave.RegisterArea[1 * 10] */
  61   76, /* FloatSave.RegisterArea[2 * 10] */
  62   86, /* FloatSave.RegisterArea[3 * 10] */
  63   96, /* FloatSave.RegisterArea[4 * 10] */
  64   106, /* FloatSave.RegisterArea[5 * 10] */
  65   116, /* FloatSave.RegisterArea[6 * 10] */
  66   126, /* FloatSave.RegisterArea[7 * 10] */
  67
  68   28, /* FloatSave.ControlWord */
  69   32, /* FloatSave.StatusWord */
  70   36, /* FloatSave.TagWord */
  71   44, /* FloatSave.ErrorSelector */
  72   40, /* FloatSave.ErrorOffset */
  73   52, /* FloatSave.DataSelector */
  74   48, /* FloatSave.DataOffset */
  75   44, /* FloatSave.ErrorSelector */
  76
  77   /* XMM0-7 */
  78   364, /* ExtendedRegisters[10*16] */
  79   380, /* ExtendedRegisters[11*16] */
  80   396, /* ExtendedRegisters[12*16] */
  81   412, /* ExtendedRegisters[13*16] */
  82   428, /* ExtendedRegisters[14*16] */
  83   444, /* ExtendedRegisters[15*16] */
  84   460, /* ExtendedRegisters[16*16] */
  85   476, /* ExtendedRegisters[17*16] */
  86
  87   /* MXCSR */
  88   228 /* ExtendedRegisters[24] */
  89 };
  90
  91 #define I386_WINDOWS_SIZEOF_GREGSET 716
  92
  93 /* Return the appropriate register set for the core section identified
  94    by SECT_NAME and SECT_SIZE.  */
  95
  96 static const struct regset *
  97 i386_windows_regset_from_core_section (struct gdbarch *gdbarch,
  98                                      const char *sect_name, size_t sect_size)
  99 {
 100   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 101
 102   if (strcmp (sect_name, ".reg") == 0
 103       && sect_size == I386_WINDOWS_SIZEOF_GREGSET)
 104     {
 105       if (tdep->gregset == NULL)
 106         tdep->gregset = regset_alloc (gdbarch, i386_supply_gregset,
 107                                       i386_collect_gregset);
 108       return tdep->gregset;
 109     }
 110
 111   return NULL;
 112 }
 113
 114 struct cpms_data
 115 {
 116   struct gdbarch *gdbarch;
 117   struct obstack *obstack;
 118   int module_count;
 119 };
 120
 121 static void
 122 core_process_module_section (bfd *abfd, asection *sect, void *obj)
 123 {
 124   struct cpms_data *data = obj;
 125   enum bfd_endian byte_order = gdbarch_byte_order (data->gdbarch);
 126
 127   char *module_name;
 128   size_t module_name_size;
 129   CORE_ADDR base_addr;
 130
 131   char *buf = NULL;
 132
 133   if (strncmp (sect->name, ".module", 7) != 0)
 134     return;
 135
 136   buf = xmalloc (bfd_get_section_size (sect) + 1);
 137   if (!buf)
 138     {
 139       printf_unfiltered ("memory allocation failed for %s\n", sect->name);
 140       goto out;
 141     }
 142   if (!bfd_get_section_contents (abfd, sect,
 143                                  buf, 0, bfd_get_section_size (sect)))
 144     goto out;
 145
 146
 147
 148   /* A DWORD (data_type) followed by struct windows_core_module_info.  */
 149
 150   base_addr =
 151     extract_unsigned_integer (buf + 4, 4, byte_order);
 152
 153   module_name_size =
 154     extract_unsigned_integer (buf + 8, 4, byte_order);
 155
 156   module_name = buf + 12;
 157   if (module_name - buf + module_name_size > bfd_get_section_size (sect))
 158     goto out;
 159
 160   /* The first module is the .exe itself.  */
 161   if (data->module_count != 0)
 162     windows_xfer_shared_library (module_name, base_addr,
 163                                  data->gdbarch, data->obstack);
 164   data->module_count++;
 165
 166 out:
 167   if (buf)
 168     xfree (buf);
 169   return;
 170 }
 171
 172 static LONGEST
 173 windows_core_xfer_shared_libraries (struct gdbarch *gdbarch,
 174                                   gdb_byte *readbuf,
 175                                   ULONGEST offset, LONGEST len)
 176 {
 177   struct obstack obstack;
 178   const char *buf;
 179   LONGEST len_avail;
 180   struct cpms_data data = { gdbarch, &obstack, 0 };
 181
 182   obstack_init (&obstack);
 183   obstack_grow_str (&obstack, "<library-list>\n");
 184   bfd_map_over_sections (core_bfd,
 185                          core_process_module_section,
 186                          &data);
 187   obstack_grow_str0 (&obstack, "</library-list>\n");
 188
 189   buf = obstack_finish (&obstack);
 190   len_avail = strlen (buf);
 191   if (offset >= len_avail)
 192     return 0;
 193
 194   if (len > len_avail - offset)
 195     len = len_avail - offset;
 196   memcpy (readbuf, buf + offset, len);
 197
 198   obstack_free (&obstack, NULL);
 199   return len;
 200 }
 201
 202 static CORE_ADDR
 203 i386_cygwin_skip_trampoline_code (struct frame_info *frame, CORE_ADDR pc)
 204 {
 205   return i386_pe_skip_trampoline_code (frame, pc, NULL);
 206 }
 207
 208 static const char *
 209 i386_cygwin_auto_wide_charset (void)
 210 {
 211   return "UTF-16";
 212 }
 213
 214 static void
 215 i386_cygwin_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 216 {
 217   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 218
 219   set_gdbarch_skip_trampoline_code (gdbarch, i386_cygwin_skip_trampoline_code);
 220
 221   set_gdbarch_skip_main_prologue (gdbarch, i386_skip_main_prologue);
 222
 223   tdep->struct_return = reg_struct_return;
 224
 225   tdep->gregset_reg_offset = i386_windows_gregset_reg_offset;
 226   tdep->gregset_num_regs = ARRAY_SIZE (i386_windows_gregset_reg_offset);
 227   tdep->sizeof_gregset = I386_WINDOWS_SIZEOF_GREGSET;
 228
 229   set_solib_ops (gdbarch, &solib_target_so_ops);
 230
 231   /* Core file support.  */
 232   set_gdbarch_regset_from_core_section
 233     (gdbarch, i386_windows_regset_from_core_section);
 234   set_gdbarch_core_xfer_shared_libraries
 235     (gdbarch, windows_core_xfer_shared_libraries);
 236
 237   set_gdbarch_auto_wide_charset (gdbarch, i386_cygwin_auto_wide_charset);
 238 }
 239
 240 static enum gdb_osabi
 241 i386_cygwin_osabi_sniffer (bfd *abfd)
 242 {
 243   char *target_name = bfd_get_target (abfd);
 244
 245   /* Interix also uses pei-i386.
 246      We need a way to distinguish between the two. */
 247   if (strcmp (target_name, "pei-i386") == 0)
 248     return GDB_OSABI_CYGWIN;
 249
 250   /* Cygwin uses elf core dumps.  Do not claim all ELF executables,
 251      check whether there is a .reg section of proper size.  */
 252   if (strcmp (target_name, "elf32-i386") == 0)
 253     {
 254       asection *section = bfd_get_section_by_name (abfd, ".reg");
 255       if (section
 256           && bfd_section_size (abfd, section) == I386_WINDOWS_SIZEOF_GREGSET)
 257         return GDB_OSABI_CYGWIN;
 258     }
 259
 260   return GDB_OSABI_UNKNOWN;
 261 }
 262
 263 /* Provide a prototype to silence -Wmissing-prototypes.  */
 264 void _initialize_i386_cygwin_tdep (void);
 265
 266 void
 267 _initialize_i386_cygwin_tdep (void)
 268 {
 269   gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_coff_flavour,
 270                                   i386_cygwin_osabi_sniffer);
 271
 272   /* Cygwin uses elf core dumps.  */
 273   gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_elf_flavour,
 274                                   i386_cygwin_osabi_sniffer);
 275
 276   gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_CYGWIN,
 277                           i386_cygwin_init_abi);
 278 }