gdb/i386-cygwin-tdep.c

   1 /* Target-dependent code for Cygwin running on i386's, for GDB.
   2
   3    Copyright (C) 2003, 2007-2012 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 #include "inferior.h"
  32
  33 /* Core file support.  */
  34
  35 /* This vector maps GDB's idea of a register's number into an address
  36    in the windows exception context vector.  */
  37
  38 static int i386_windows_gregset_reg_offset[] =
  39 {
  40   176, /* eax */
  41   172, /* ecx */
  42   168, /* edx */
  43   164, /* ebx */
  44
  45   196, /* esp */
  46   180, /* ebp */
  47   160, /* esi */
  48   156, /* edi */
  49
  50   184, /* eip */
  51   192, /* eflags */
  52   188, /* cs */
  53   200, /* ss */
  54
  55   152, /* ds */
  56   148, /* es */
  57   144, /* fs */
  58   140, /* gs */
  59
  60   56, /* FloatSave.RegisterArea[0 * 10] */
  61   66, /* FloatSave.RegisterArea[1 * 10] */
  62   76, /* FloatSave.RegisterArea[2 * 10] */
  63   86, /* FloatSave.RegisterArea[3 * 10] */
  64   96, /* FloatSave.RegisterArea[4 * 10] */
  65   106, /* FloatSave.RegisterArea[5 * 10] */
  66   116, /* FloatSave.RegisterArea[6 * 10] */
  67   126, /* FloatSave.RegisterArea[7 * 10] */
  68
  69   28, /* FloatSave.ControlWord */
  70   32, /* FloatSave.StatusWord */
  71   36, /* FloatSave.TagWord */
  72   44, /* FloatSave.ErrorSelector */
  73   40, /* FloatSave.ErrorOffset */
  74   52, /* FloatSave.DataSelector */
  75   48, /* FloatSave.DataOffset */
  76   44, /* FloatSave.ErrorSelector */
  77
  78   /* XMM0-7 */
  79   364, /* ExtendedRegisters[10*16] */
  80   380, /* ExtendedRegisters[11*16] */
  81   396, /* ExtendedRegisters[12*16] */
  82   412, /* ExtendedRegisters[13*16] */
  83   428, /* ExtendedRegisters[14*16] */
  84   444, /* ExtendedRegisters[15*16] */
  85   460, /* ExtendedRegisters[16*16] */
  86   476, /* ExtendedRegisters[17*16] */
  87
  88   /* MXCSR */
  89   228 /* ExtendedRegisters[24] */
  90 };
  91
  92 #define I386_WINDOWS_SIZEOF_GREGSET 716
  93
  94 /* Return the appropriate register set for the core section identified
  95    by SECT_NAME and SECT_SIZE.  */
  96
  97 static const struct regset *
  98 i386_windows_regset_from_core_section (struct gdbarch *gdbarch,
  99                                      const char *sect_name, size_t sect_size)
 100 {
 101   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 102
 103   if (strcmp (sect_name, ".reg") == 0
 104       && sect_size == I386_WINDOWS_SIZEOF_GREGSET)
 105     {
 106       if (tdep->gregset == NULL)
 107         tdep->gregset = regset_alloc (gdbarch, i386_supply_gregset,
 108                                       i386_collect_gregset);
 109       return tdep->gregset;
 110     }
 111
 112   return NULL;
 113 }
 114
 115 struct cpms_data
 116 {
 117   struct gdbarch *gdbarch;
 118   struct obstack *obstack;
 119   int module_count;
 120 };
 121
 122 static void
 123 core_process_module_section (bfd *abfd, asection *sect, void *obj)
 124 {
 125   struct cpms_data *data = obj;
 126   enum bfd_endian byte_order = gdbarch_byte_order (data->gdbarch);
 127
 128   char *module_name;
 129   size_t module_name_size;
 130   CORE_ADDR base_addr;
 131
 132   char *buf = NULL;
 133
 134   if (strncmp (sect->name, ".module", 7) != 0)
 135     return;
 136
 137   buf = xmalloc (bfd_get_section_size (sect) + 1);
 138   if (!buf)
 139     {
 140       printf_unfiltered ("memory allocation failed for %s\n", sect->name);
 141       goto out;
 142     }
 143   if (!bfd_get_section_contents (abfd, sect,
 144                                  buf, 0, bfd_get_section_size (sect)))
 145     goto out;
 146
 147
 148
 149   /* A DWORD (data_type) followed by struct windows_core_module_info.  */
 150
 151   base_addr =
 152     extract_unsigned_integer (buf + 4, 4, byte_order);
 153
 154   module_name_size =
 155     extract_unsigned_integer (buf + 8, 4, byte_order);
 156
 157   module_name = buf + 12;
 158   if (module_name - buf + module_name_size > bfd_get_section_size (sect))
 159     goto out;
 160
 161   /* The first module is the .exe itself.  */
 162   if (data->module_count != 0)
 163     windows_xfer_shared_library (module_name, base_addr,
 164                                  data->gdbarch, data->obstack);
 165   data->module_count++;
 166
 167 out:
 168   if (buf)
 169     xfree (buf);
 170   return;
 171 }
 172
 173 static LONGEST
 174 windows_core_xfer_shared_libraries (struct gdbarch *gdbarch,
 175                                   gdb_byte *readbuf,
 176                                   ULONGEST offset, LONGEST len)
 177 {
 178   struct obstack obstack;
 179   const char *buf;
 180   LONGEST len_avail;
 181   struct cpms_data data = { gdbarch, &obstack, 0 };
 182
 183   obstack_init (&obstack);
 184   obstack_grow_str (&obstack, "<library-list>\n");
 185   bfd_map_over_sections (core_bfd,
 186                          core_process_module_section,
 187                          &data);
 188   obstack_grow_str0 (&obstack, "</library-list>\n");
 189
 190   buf = obstack_finish (&obstack);
 191   len_avail = strlen (buf);
 192   if (offset >= len_avail)
 193     return 0;
 194
 195   if (len > len_avail - offset)
 196     len = len_avail - offset;
 197   memcpy (readbuf, buf + offset, len);
 198
 199   obstack_free (&obstack, NULL);
 200   return len;
 201 }
 202
 203 /* This is how we want PTIDs from core files to be printed.  */
 204
 205 static char *
 206 i386_windows_core_pid_to_str (struct gdbarch *gdbarch, ptid_t ptid)
 207 {
 208   static char buf[80];
 209
 210   if (ptid_get_lwp (ptid) != 0)
 211     {
 212       snprintf (buf, sizeof (buf), "Thread 0x%lx", ptid_get_lwp (ptid));
 213       return buf;
 214     }
 215
 216   return normal_pid_to_str (ptid);
 217 }
 218
 219 static CORE_ADDR
 220 i386_cygwin_skip_trampoline_code (struct frame_info *frame, CORE_ADDR pc)
 221 {
 222   return i386_pe_skip_trampoline_code (frame, pc, NULL);
 223 }
 224
 225 static const char *
 226 i386_cygwin_auto_wide_charset (void)
 227 {
 228   return "UTF-16";
 229 }
 230
 231 static void
 232 i386_cygwin_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 233 {
 234   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 235
 236   set_gdbarch_skip_trampoline_code (gdbarch, i386_cygwin_skip_trampoline_code);
 237
 238   set_gdbarch_skip_main_prologue (gdbarch, i386_skip_main_prologue);
 239
 240   tdep->struct_return = reg_struct_return;
 241
 242   tdep->gregset_reg_offset = i386_windows_gregset_reg_offset;
 243   tdep->gregset_num_regs = ARRAY_SIZE (i386_windows_gregset_reg_offset);
 244   tdep->sizeof_gregset = I386_WINDOWS_SIZEOF_GREGSET;
 245
 246   set_solib_ops (gdbarch, &solib_target_so_ops);
 247
 248   /* Core file support.  */
 249   set_gdbarch_regset_from_core_section
 250     (gdbarch, i386_windows_regset_from_core_section);
 251   set_gdbarch_core_xfer_shared_libraries
 252     (gdbarch, windows_core_xfer_shared_libraries);
 253   set_gdbarch_core_pid_to_str (gdbarch, i386_windows_core_pid_to_str);
 254
 255   set_gdbarch_auto_wide_charset (gdbarch, i386_cygwin_auto_wide_charset);
 256
 257   /* Canonical paths on this target look like
 258      `c:\Program Files\Foo App\mydll.dll', for example.  */
 259   set_gdbarch_has_dos_based_file_system (gdbarch, 1);
 260
 261   set_gdbarch_iterate_over_objfiles_in_search_order
 262     (gdbarch, windows_iterate_over_objfiles_in_search_order);
 263 }
 264
 265 static enum gdb_osabi
 266 i386_cygwin_osabi_sniffer (bfd *abfd)
 267 {
 268   char *target_name = bfd_get_target (abfd);
 269
 270   /* Interix also uses pei-i386.
 271      We need a way to distinguish between the two.  */
 272   if (strcmp (target_name, "pei-i386") == 0)
 273     return GDB_OSABI_CYGWIN;
 274
 275   /* Cygwin uses elf core dumps.  Do not claim all ELF executables,
 276      check whether there is a .reg section of proper size.  */
 277   if (strcmp (target_name, "elf32-i386") == 0)
 278     {
 279       asection *section = bfd_get_section_by_name (abfd, ".reg");
 280       if (section
 281           && bfd_section_size (abfd, section) == I386_WINDOWS_SIZEOF_GREGSET)
 282         return GDB_OSABI_CYGWIN;
 283     }
 284
 285   return GDB_OSABI_UNKNOWN;
 286 }
 287
 288 /* Provide a prototype to silence -Wmissing-prototypes.  */
 289 void _initialize_i386_cygwin_tdep (void);
 290
 291 void
 292 _initialize_i386_cygwin_tdep (void)
 293 {
 294   gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_coff_flavour,
 295                                   i386_cygwin_osabi_sniffer);
 296
 297   /* Cygwin uses elf core dumps.  */
 298   gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_elf_flavour,
 299                                   i386_cygwin_osabi_sniffer);
 300
 301   gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_CYGWIN,
 302                           i386_cygwin_init_abi);
 303 }