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, 2011
   4    Free Software Foundation, Inc.
   5
   6    This file is part of GDB.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  20
  21 #include "defs.h"
  22 #include "osabi.h"
  23 #include "gdb_string.h"
  24 #include "i386-tdep.h"
  25 #include "windows-tdep.h"
  26 #include "regset.h"
  27 #include "gdb_obstack.h"
  28 #include "xml-support.h"
  29 #include "gdbcore.h"
  30 #include "solib.h"
  31 #include "solib-target.h"
  32 #include "inferior.h"
  33
  34 /* Core file support.  */
  35
  36 /* This vector maps GDB's idea of a register's number into an address
  37    in the windows exception context vector.  */
  38
  39 static int i386_windows_gregset_reg_offset[] =
  40 {
  41   176, /* eax */
  42   172, /* ecx */
  43   168, /* edx */
  44   164, /* ebx */
  45
  46   196, /* esp */
  47   180, /* ebp */
  48   160, /* esi */
  49   156, /* edi */
  50
  51   184, /* eip */
  52   192, /* eflags */
  53   188, /* cs */
  54   200, /* ss */
  55
  56   152, /* ds */
  57   148, /* es */
  58   144, /* fs */
  59   140, /* gs */
  60
  61   56, /* FloatSave.RegisterArea[0 * 10] */
  62   66, /* FloatSave.RegisterArea[1 * 10] */
  63   76, /* FloatSave.RegisterArea[2 * 10] */
  64   86, /* FloatSave.RegisterArea[3 * 10] */
  65   96, /* FloatSave.RegisterArea[4 * 10] */
  66   106, /* FloatSave.RegisterArea[5 * 10] */
  67   116, /* FloatSave.RegisterArea[6 * 10] */
  68   126, /* FloatSave.RegisterArea[7 * 10] */
  69
  70   28, /* FloatSave.ControlWord */
  71   32, /* FloatSave.StatusWord */
  72   36, /* FloatSave.TagWord */
  73   44, /* FloatSave.ErrorSelector */
  74   40, /* FloatSave.ErrorOffset */
  75   52, /* FloatSave.DataSelector */
  76   48, /* FloatSave.DataOffset */
  77   44, /* FloatSave.ErrorSelector */
  78
  79   /* XMM0-7 */
  80   364, /* ExtendedRegisters[10*16] */
  81   380, /* ExtendedRegisters[11*16] */
  82   396, /* ExtendedRegisters[12*16] */
  83   412, /* ExtendedRegisters[13*16] */
  84   428, /* ExtendedRegisters[14*16] */
  85   444, /* ExtendedRegisters[15*16] */
  86   460, /* ExtendedRegisters[16*16] */
  87   476, /* ExtendedRegisters[17*16] */
  88
  89   /* MXCSR */
  90   228 /* ExtendedRegisters[24] */
  91 };
  92
  93 #define I386_WINDOWS_SIZEOF_GREGSET 716
  94
  95 /* Return the appropriate register set for the core section identified
  96    by SECT_NAME and SECT_SIZE.  */
  97
  98 static const struct regset *
  99 i386_windows_regset_from_core_section (struct gdbarch *gdbarch,
 100                                      const char *sect_name, size_t sect_size)
 101 {
 102   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 103
 104   if (strcmp (sect_name, ".reg") == 0
 105       && sect_size == I386_WINDOWS_SIZEOF_GREGSET)
 106     {
 107       if (tdep->gregset == NULL)
 108         tdep->gregset = regset_alloc (gdbarch, i386_supply_gregset,
 109                                       i386_collect_gregset);
 110       return tdep->gregset;
 111     }
 112
 113   return NULL;
 114 }
 115
 116 struct cpms_data
 117 {
 118   struct gdbarch *gdbarch;
 119   struct obstack *obstack;
 120   int module_count;
 121 };
 122
 123 static void
 124 core_process_module_section (bfd *abfd, asection *sect, void *obj)
 125 {
 126   struct cpms_data *data = obj;
 127   enum bfd_endian byte_order = gdbarch_byte_order (data->gdbarch);
 128
 129   char *module_name;
 130   size_t module_name_size;
 131   CORE_ADDR base_addr;
 132
 133   char *buf = NULL;
 134
 135   if (strncmp (sect->name, ".module", 7) != 0)
 136     return;
 137
 138   buf = xmalloc (bfd_get_section_size (sect) + 1);
 139   if (!buf)
 140     {
 141       printf_unfiltered ("memory allocation failed for %s\n", sect->name);
 142       goto out;
 143     }
 144   if (!bfd_get_section_contents (abfd, sect,
 145                                  buf, 0, bfd_get_section_size (sect)))
 146     goto out;
 147
 148
 149
 150   /* A DWORD (data_type) followed by struct windows_core_module_info.  */
 151
 152   base_addr =
 153     extract_unsigned_integer (buf + 4, 4, byte_order);
 154
 155   module_name_size =
 156     extract_unsigned_integer (buf + 8, 4, byte_order);
 157
 158   module_name = buf + 12;
 159   if (module_name - buf + module_name_size > bfd_get_section_size (sect))
 160     goto out;
 161
 162   /* The first module is the .exe itself.  */
 163   if (data->module_count != 0)
 164     windows_xfer_shared_library (module_name, base_addr,
 165                                  data->gdbarch, data->obstack);
 166   data->module_count++;
 167
 168 out:
 169   if (buf)
 170     xfree (buf);
 171   return;
 172 }
 173
 174 static LONGEST
 175 windows_core_xfer_shared_libraries (struct gdbarch *gdbarch,
 176                                   gdb_byte *readbuf,
 177                                   ULONGEST offset, LONGEST len)
 178 {
 179   struct obstack obstack;
 180   const char *buf;
 181   LONGEST len_avail;
 182   struct cpms_data data = { gdbarch, &obstack, 0 };
 183
 184   obstack_init (&obstack);
 185   obstack_grow_str (&obstack, "<library-list>\n");
 186   bfd_map_over_sections (core_bfd,
 187                          core_process_module_section,
 188                          &data);
 189   obstack_grow_str0 (&obstack, "</library-list>\n");
 190
 191   buf = obstack_finish (&obstack);
 192   len_avail = strlen (buf);
 193   if (offset >= len_avail)
 194     return 0;
 195
 196   if (len > len_avail - offset)
 197     len = len_avail - offset;
 198   memcpy (readbuf, buf + offset, len);
 199
 200   obstack_free (&obstack, NULL);
 201   return len;
 202 }
 203
 204 /* This is how we want PTIDs from core files to be printed.  */
 205
 206 static char *
 207 i386_windows_core_pid_to_str (struct gdbarch *gdbarch, ptid_t ptid)
 208 {
 209   static char buf[80];
 210
 211   if (ptid_get_lwp (ptid) != 0)
 212     {
 213       snprintf (buf, sizeof (buf), "Thread 0x%lx", ptid_get_lwp (ptid));
 214       return buf;
 215     }
 216
 217   return normal_pid_to_str (ptid);
 218 }
 219
 220 static CORE_ADDR
 221 i386_cygwin_skip_trampoline_code (struct frame_info *frame, CORE_ADDR pc)
 222 {
 223   return i386_pe_skip_trampoline_code (frame, pc, NULL);
 224 }
 225
 226 static const char *
 227 i386_cygwin_auto_wide_charset (void)
 228 {
 229   return "UTF-16";
 230 }
 231
 232 static void
 233 i386_cygwin_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 234 {
 235   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 236
 237   set_gdbarch_skip_trampoline_code (gdbarch, i386_cygwin_skip_trampoline_code);
 238
 239   set_gdbarch_skip_main_prologue (gdbarch, i386_skip_main_prologue);
 240
 241   tdep->struct_return = reg_struct_return;
 242
 243   tdep->gregset_reg_offset = i386_windows_gregset_reg_offset;
 244   tdep->gregset_num_regs = ARRAY_SIZE (i386_windows_gregset_reg_offset);
 245   tdep->sizeof_gregset = I386_WINDOWS_SIZEOF_GREGSET;
 246
 247   set_solib_ops (gdbarch, &solib_target_so_ops);
 248
 249   /* Core file support.  */
 250   set_gdbarch_regset_from_core_section
 251     (gdbarch, i386_windows_regset_from_core_section);
 252   set_gdbarch_core_xfer_shared_libraries
 253     (gdbarch, windows_core_xfer_shared_libraries);
 254   set_gdbarch_core_pid_to_str (gdbarch, i386_windows_core_pid_to_str);
 255
 256   set_gdbarch_auto_wide_charset (gdbarch, i386_cygwin_auto_wide_charset);
 257
 258   /* Canonical paths on this target look like
 259      `c:\Program Files\Foo App\mydll.dll', for example.  */
 260   set_gdbarch_has_dos_based_file_system (gdbarch, 1);
 261 }
 262
 263 static enum gdb_osabi
 264 i386_cygwin_osabi_sniffer (bfd *abfd)
 265 {
 266   char *target_name = bfd_get_target (abfd);
 267
 268   /* Interix also uses pei-i386.
 269      We need a way to distinguish between the two.  */
 270   if (strcmp (target_name, "pei-i386") == 0)
 271     return GDB_OSABI_CYGWIN;
 272
 273   /* Cygwin uses elf core dumps.  Do not claim all ELF executables,
 274      check whether there is a .reg section of proper size.  */
 275   if (strcmp (target_name, "elf32-i386") == 0)
 276     {
 277       asection *section = bfd_get_section_by_name (abfd, ".reg");
 278       if (section
 279           && bfd_section_size (abfd, section) == I386_WINDOWS_SIZEOF_GREGSET)
 280         return GDB_OSABI_CYGWIN;
 281     }
 282
 283   return GDB_OSABI_UNKNOWN;
 284 }
 285
 286 /* Provide a prototype to silence -Wmissing-prototypes.  */
 287 void _initialize_i386_cygwin_tdep (void);
 288
 289 void
 290 _initialize_i386_cygwin_tdep (void)
 291 {
 292   gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_coff_flavour,
 293                                   i386_cygwin_osabi_sniffer);
 294
 295   /* Cygwin uses elf core dumps.  */
 296   gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_elf_flavour,
 297                                   i386_cygwin_osabi_sniffer);
 298
 299   gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_CYGWIN,
 300                           i386_cygwin_init_abi);
 301 }