gdb/i386-windows-tdep.c

   1 /* Target-dependent code for Windows (including Cygwin) running on i386's,
   2    for GDB.
   3
   4    Copyright (C) 2003-2020 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 "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 "inferior.h"
  30
  31 /* Core file support.  */
  32
  33 /* This vector maps GDB's idea of a register's number into an address
  34    in the windows exception context vector.  */
  35
  36 static int i386_windows_gregset_reg_offset[] =
  37 {
  38   176, /* eax */
  39   172, /* ecx */
  40   168, /* edx */
  41   164, /* ebx */
  42
  43   196, /* esp */
  44   180, /* ebp */
  45   160, /* esi */
  46   156, /* edi */
  47
  48   184, /* eip */
  49   192, /* eflags */
  50   188, /* cs */
  51   200, /* ss */
  52
  53   152, /* ds */
  54   148, /* es */
  55   144, /* fs */
  56   140, /* gs */
  57
  58   56, /* FloatSave.RegisterArea[0 * 10] */
  59   66, /* FloatSave.RegisterArea[1 * 10] */
  60   76, /* FloatSave.RegisterArea[2 * 10] */
  61   86, /* FloatSave.RegisterArea[3 * 10] */
  62   96, /* FloatSave.RegisterArea[4 * 10] */
  63   106, /* FloatSave.RegisterArea[5 * 10] */
  64   116, /* FloatSave.RegisterArea[6 * 10] */
  65   126, /* FloatSave.RegisterArea[7 * 10] */
  66
  67   28, /* FloatSave.ControlWord */
  68   32, /* FloatSave.StatusWord */
  69   36, /* FloatSave.TagWord */
  70   44, /* FloatSave.ErrorSelector */
  71   40, /* FloatSave.ErrorOffset */
  72   52, /* FloatSave.DataSelector */
  73   48, /* FloatSave.DataOffset */
  74   44, /* FloatSave.ErrorSelector */
  75
  76   /* XMM0-7 */
  77   364, /* ExtendedRegisters[10*16] */
  78   380, /* ExtendedRegisters[11*16] */
  79   396, /* ExtendedRegisters[12*16] */
  80   412, /* ExtendedRegisters[13*16] */
  81   428, /* ExtendedRegisters[14*16] */
  82   444, /* ExtendedRegisters[15*16] */
  83   460, /* ExtendedRegisters[16*16] */
  84   476, /* ExtendedRegisters[17*16] */
  85
  86   /* MXCSR */
  87   228 /* ExtendedRegisters[24] */
  88 };
  89
  90 #define I386_WINDOWS_SIZEOF_GREGSET 716
  91
  92 struct cpms_data
  93 {
  94   struct gdbarch *gdbarch;
  95   struct obstack *obstack;
  96   int module_count;
  97 };
  98
  99 static void
 100 core_process_module_section (bfd *abfd, asection *sect, void *obj)
 101 {
 102   struct cpms_data *data = (struct cpms_data *) obj;
 103   enum bfd_endian byte_order = gdbarch_byte_order (data->gdbarch);
 104
 105   char *module_name;
 106   size_t module_name_size;
 107   CORE_ADDR base_addr;
 108
 109   gdb_byte *buf = NULL;
 110
 111   if (!startswith (sect->name, ".module"))
 112     return;
 113
 114   buf = (gdb_byte *) xmalloc (bfd_section_size (sect) + 1);
 115   if (!buf)
 116     {
 117       printf_unfiltered ("memory allocation failed for %s\n", sect->name);
 118       goto out;
 119     }
 120   if (!bfd_get_section_contents (abfd, sect,
 121                                  buf, 0, bfd_section_size (sect)))
 122     goto out;
 123
 124
 125
 126   /* A DWORD (data_type) followed by struct windows_core_module_info.  */
 127
 128   base_addr =
 129     extract_unsigned_integer (buf + 4, 4, byte_order);
 130
 131   module_name_size =
 132     extract_unsigned_integer (buf + 8, 4, byte_order);
 133
 134   if (12 + module_name_size > bfd_section_size (sect))
 135     goto out;
 136   module_name = (char *) buf + 12;
 137
 138   /* The first module is the .exe itself.  */
 139   if (data->module_count != 0)
 140     windows_xfer_shared_library (module_name, base_addr,
 141                                  NULL, data->gdbarch, data->obstack);
 142   data->module_count++;
 143
 144 out:
 145   if (buf)
 146     xfree (buf);
 147   return;
 148 }
 149
 150 static ULONGEST
 151 windows_core_xfer_shared_libraries (struct gdbarch *gdbarch,
 152                                   gdb_byte *readbuf,
 153                                   ULONGEST offset, ULONGEST len)
 154 {
 155   struct obstack obstack;
 156   const char *buf;
 157   ULONGEST len_avail;
 158   struct cpms_data data = { gdbarch, &obstack, 0 };
 159
 160   obstack_init (&obstack);
 161   obstack_grow_str (&obstack, "<library-list>\n");
 162   bfd_map_over_sections (core_bfd,
 163                          core_process_module_section,
 164                          &data);
 165   obstack_grow_str0 (&obstack, "</library-list>\n");
 166
 167   buf = (const char *) obstack_finish (&obstack);
 168   len_avail = strlen (buf);
 169   if (offset >= len_avail)
 170     return 0;
 171
 172   if (len > len_avail - offset)
 173     len = len_avail - offset;
 174   memcpy (readbuf, buf + offset, len);
 175
 176   obstack_free (&obstack, NULL);
 177   return len;
 178 }
 179
 180 /* This is how we want PTIDs from core files to be printed.  */
 181
 182 static std::string
 183 i386_windows_core_pid_to_str (struct gdbarch *gdbarch, ptid_t ptid)
 184 {
 185   if (ptid.lwp () != 0)
 186     return string_printf ("Thread 0x%lx", ptid.lwp ());
 187
 188   return normal_pid_to_str (ptid);
 189 }
 190
 191 static CORE_ADDR
 192 i386_windows_skip_trampoline_code (struct frame_info *frame, CORE_ADDR pc)
 193 {
 194   return i386_pe_skip_trampoline_code (frame, pc, NULL);
 195 }
 196
 197 static const char *
 198 i386_windows_auto_wide_charset (void)
 199 {
 200   return "UTF-16";
 201 }
 202
 203 static void
 204 i386_windows_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 205 {
 206   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 207
 208   windows_init_abi (info, gdbarch);
 209
 210   set_gdbarch_skip_trampoline_code (gdbarch, i386_windows_skip_trampoline_code);
 211
 212   set_gdbarch_skip_main_prologue (gdbarch, i386_skip_main_prologue);
 213
 214   tdep->struct_return = reg_struct_return;
 215
 216   tdep->gregset_reg_offset = i386_windows_gregset_reg_offset;
 217   tdep->gregset_num_regs = ARRAY_SIZE (i386_windows_gregset_reg_offset);
 218   tdep->sizeof_gregset = I386_WINDOWS_SIZEOF_GREGSET;
 219
 220   tdep->sizeof_fpregset = 0;
 221
 222   /* Core file support.  */
 223   set_gdbarch_core_xfer_shared_libraries
 224     (gdbarch, windows_core_xfer_shared_libraries);
 225   set_gdbarch_core_pid_to_str (gdbarch, i386_windows_core_pid_to_str);
 226
 227   set_gdbarch_auto_wide_charset (gdbarch, i386_windows_auto_wide_charset);
 228 }
 229
 230 static gdb_osabi
 231 i386_windows_osabi_sniffer (bfd *abfd)
 232 {
 233   const char *target_name = bfd_get_target (abfd);
 234
 235   if (!streq (target_name, "pei-i386"))
 236     return GDB_OSABI_UNKNOWN;
 237
 238   if (is_linked_with_cygwin_dll (abfd))
 239     return GDB_OSABI_CYGWIN;
 240
 241   return GDB_OSABI_WINDOWS;
 242 }
 243
 244 static enum gdb_osabi
 245 i386_cygwin_core_osabi_sniffer (bfd *abfd)
 246 {
 247   const char *target_name = bfd_get_target (abfd);
 248
 249   /* Cygwin uses elf core dumps.  Do not claim all ELF executables,
 250      check whether there is a .reg section of proper size.  */
 251   if (strcmp (target_name, "elf32-i386") == 0)
 252     {
 253       asection *section = bfd_get_section_by_name (abfd, ".reg");
 254       if (section != nullptr
 255           && bfd_section_size (section) == I386_WINDOWS_SIZEOF_GREGSET)
 256         return GDB_OSABI_CYGWIN;
 257     }
 258
 259   return GDB_OSABI_UNKNOWN;
 260 }
 261
 262 void _initialize_i386_windows_tdep ();
 263 void
 264 _initialize_i386_windows_tdep ()
 265 {
 266   gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_coff_flavour,
 267                                   i386_windows_osabi_sniffer);
 268
 269   /* Cygwin uses elf core dumps.  */
 270   gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_elf_flavour,
 271                                   i386_cygwin_core_osabi_sniffer);
 272
 273   /* The Windows and Cygwin OS ABIs are currently equivalent on i386.  */
 274   gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_WINDOWS,
 275                           i386_windows_init_abi);
 276   gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_CYGWIN,
 277                           i386_windows_init_abi);
 278 }