bfd/hpux-core.c

   1 /* BFD back-end for HP/UX core files.
   2    Copyright (C) 1993-2021 Free Software Foundation, Inc.
   3    Written by Stu Grossman, Cygnus Support.
   4    Converted to back-end form by Ian Lance Taylor, Cygnus SUpport
   5
   6    This file is part of BFD, the Binary File Descriptor library.
   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, write to the Free Software
  20    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  21    MA 02110-1301, USA.  */
  22
  23
  24 /* This file can only be compiled on systems which use HP/UX style
  25    core files.  */
  26
  27 #include "sysdep.h"
  28 #include "bfd.h"
  29 #include "libbfd.h"
  30
  31 #if defined (HOST_HPPAHPUX) || defined (HOST_HPPAMPEIX)
  32
  33 /* FIXME: sys/core.h doesn't exist for HPUX version 7.  HPUX version
  34    5, 6, and 7 core files seem to be standard trad-core.c type core
  35    files; can we just use trad-core.c in addition to this file?  */
  36
  37 #include <sys/core.h>
  38 #include <sys/utsname.h>
  39
  40 #endif /* HOST_HPPAHPUX */
  41
  42 #ifdef HOST_HPPABSD
  43
  44 /* Not a very swift place to put it, but that's where the BSD port
  45    puts them.  */
  46 #include "/hpux/usr/include/sys/core.h"
  47
  48 #endif /* HOST_HPPABSD */
  49
  50 #include <sys/param.h>
  51 #include <dirent.h>
  52 #include <signal.h>
  53 #ifdef HPUX_CORE
  54 #include <machine/reg.h>
  55 #endif
  56 #include <sys/file.h>
  57
  58 /* Kludge: There's no explicit mechanism provided by sys/core.h to
  59    conditionally know whether a proc_info has thread id fields.
  60    However, CORE_ANON_SHMEM shows up first at 10.30, which is
  61    happily also when meaningful thread id's show up in proc_info. */
  62 #if defined(CORE_ANON_SHMEM)
  63 #define PROC_INFO_HAS_THREAD_ID (1)
  64 #endif
  65
  66 /* This type appears at HP-UX 10.30.  Defining it if not defined
  67    by sys/core.h allows us to build for older HP-UX's, and (since
  68    it won't be encountered in core-dumps from older HP-UX's) is
  69    harmless. */
  70 #if !defined(CORE_ANON_SHMEM)
  71 #define CORE_ANON_SHMEM 0x00000200         /* anonymous shared memory */
  72 #endif
  73
  74 /* These are stored in the bfd's tdata */
  75
  76 /* .lwpid and .user_tid are only valid if PROC_INFO_HAS_THREAD_ID, else they
  77    are set to 0.  Also, until HP-UX implements MxN threads, .user_tid and
  78    .lwpid are synonymous. */
  79 struct hpux_core_struct
  80 {
  81   int sig;
  82   int lwpid;               /* Kernel thread ID. */
  83   unsigned long user_tid;  /* User thread ID. */
  84   char cmd[MAXCOMLEN + 1];
  85 };
  86
  87 #define core_hdr(bfd) ((bfd)->tdata.hpux_core_data)
  88 #define core_signal(bfd) (core_hdr(bfd)->sig)
  89 #define core_command(bfd) (core_hdr(bfd)->cmd)
  90 #define core_kernel_thread_id(bfd) (core_hdr(bfd)->lwpid)
  91 #define core_user_thread_id(bfd) (core_hdr(bfd)->user_tid)
  92 #define hpux_core_core_file_matches_executable_p generic_core_file_matches_executable_p
  93 #define hpux_core_core_file_pid _bfd_nocore_core_file_pid
  94
  95 static asection *make_bfd_asection (bfd *, const char *, flagword,
  96                                     bfd_size_type, bfd_vma, unsigned int);
  97 static bfd_cleanup hpux_core_core_file_p (bfd *);
  98 static char *hpux_core_core_file_failing_command (bfd *);
  99 static int hpux_core_core_file_failing_signal (bfd *);
 100 static void swap_abort (void);
 101
 102 static asection *
 103 make_bfd_asection (bfd *abfd, const char *name, flagword flags,
 104                    bfd_size_type size, bfd_vma vma,
 105                    unsigned int alignment_power)
 106 {
 107   asection *asect;
 108   char *newname;
 109
 110   newname = bfd_alloc (abfd, (bfd_size_type) strlen (name) + 1);
 111   if (!newname)
 112     return NULL;
 113
 114   strcpy (newname, name);
 115
 116   asect = bfd_make_section_anyway_with_flags (abfd, newname, flags);
 117   if (!asect)
 118     return NULL;
 119
 120   asect->size = size;
 121   asect->vma = vma;
 122   asect->filepos = bfd_tell (abfd);
 123   asect->alignment_power = alignment_power;
 124
 125   return asect;
 126 }
 127
 128 /* Return true if the given core file section corresponds to a thread,
 129    based on its name.  */
 130
 131 static int
 132 thread_section_p (bfd *abfd ATTRIBUTE_UNUSED,
 133                   asection *sect,
 134                   void *obj ATTRIBUTE_UNUSED)
 135 {
 136   return startswith (sect->name, ".reg/");
 137 }
 138
 139 /* this function builds a bfd target if the file is a corefile.
 140    It returns null or 0 if it finds out thaat it is not a core file.
 141    The way it checks this is by looking for allowed 'type' field values.
 142    These are declared in sys/core.h
 143    There are some values which are 'reserved for future use'. In particular
 144    CORE_NONE is actually defined as 0. This may be a catch-all for cases
 145    in which the core file is generated by some non-hpux application.
 146    (I am just guessing here!)
 147 */
 148 static bfd_cleanup
 149 hpux_core_core_file_p (bfd *abfd)
 150 {
 151   int  good_sections = 0;
 152   int  unknown_sections = 0;
 153
 154   core_hdr (abfd) = (struct hpux_core_struct *)
 155     bfd_zalloc (abfd, (bfd_size_type) sizeof (struct hpux_core_struct));
 156   if (!core_hdr (abfd))
 157     return NULL;
 158
 159   while (1)
 160     {
 161       int val;
 162       struct corehead core_header;
 163
 164       val = bfd_bread ((void *) &core_header,
 165                       (bfd_size_type) sizeof core_header, abfd);
 166       if (val <= 0)
 167         break;
 168       switch (core_header.type)
 169         {
 170         case CORE_KERNEL:
 171         case CORE_FORMAT:
 172           /* Just skip this.  */
 173           bfd_seek (abfd, (file_ptr) core_header.len, SEEK_CUR);
 174           good_sections++;
 175           break;
 176         case CORE_EXEC:
 177           {
 178             struct proc_exec proc_exec;
 179             if (bfd_bread ((void *) &proc_exec, (bfd_size_type) core_header.len,
 180                           abfd) != core_header.len)
 181               break;
 182             strncpy (core_command (abfd), proc_exec.cmd, MAXCOMLEN + 1);
 183             good_sections++;
 184           }
 185           break;
 186         case CORE_PROC:
 187           {
 188             struct proc_info proc_info;
 189             char  secname[100];  /* Of arbitrary size, but plenty large. */
 190
 191             /* We need to read this section, 'cause we need to determine
 192                whether the core-dumped app was threaded before we create
 193                any .reg sections. */
 194             if (bfd_bread (&proc_info, (bfd_size_type) core_header.len, abfd)
 195                 != core_header.len)
 196               break;
 197
 198               /* However, we also want to create those sections with the
 199                  file positioned at the start of the record, it seems. */
 200             if (bfd_seek (abfd, -((file_ptr) core_header.len), SEEK_CUR) != 0)
 201               break;
 202
 203 #if defined(PROC_INFO_HAS_THREAD_ID)
 204             core_kernel_thread_id (abfd) = proc_info.lwpid;
 205             core_user_thread_id (abfd) = proc_info.user_tid;
 206 #else
 207             core_kernel_thread_id (abfd) = 0;
 208             core_user_thread_id (abfd) = 0;
 209 #endif
 210             /* If the program was unthreaded, then we'll just create a
 211                .reg section.
 212
 213                If the program was threaded, then we'll create .reg/XXXXX
 214                section for each thread, where XXXXX is a printable
 215                representation of the kernel thread id.  We'll also
 216                create a .reg section for the thread that was running
 217                and signalled at the time of the core-dump (i.e., this
 218                is effectively an alias, needed to keep GDB happy.)
 219
 220                Note that we use `.reg/XXXXX' as opposed to '.regXXXXX'
 221                because GDB expects that .reg2 will be the floating-
 222                point registers. */
 223             if (core_kernel_thread_id (abfd) == 0)
 224               {
 225                 if (!make_bfd_asection (abfd, ".reg",
 226                                         SEC_HAS_CONTENTS,
 227                                         core_header.len,
 228                                         (bfd_vma) offsetof (struct proc_info,
 229                                                             hw_regs),
 230                                         2))
 231                   goto fail;
 232               }
 233             else
 234               {
 235                 /* There are threads.  Is this the one that caused the
 236                    core-dump?  We'll claim it was the running thread. */
 237                 if (proc_info.sig != -1)
 238                   {
 239                     if (!make_bfd_asection (abfd, ".reg",
 240                                             SEC_HAS_CONTENTS,
 241                                             core_header.len,
 242                                             (bfd_vma)offsetof (struct proc_info,
 243                                                                hw_regs),
 244                                             2))
 245                       goto fail;
 246                   }
 247                 /* We always make one of these sections, for every thread. */
 248                 sprintf (secname, ".reg/%d", core_kernel_thread_id (abfd));
 249                 if (!make_bfd_asection (abfd, secname,
 250                                         SEC_HAS_CONTENTS,
 251                                         core_header.len,
 252                                         (bfd_vma) offsetof (struct proc_info,
 253                                                             hw_regs),
 254                                         2))
 255                   goto fail;
 256               }
 257             core_signal (abfd) = proc_info.sig;
 258             if (bfd_seek (abfd, (file_ptr) core_header.len, SEEK_CUR) != 0)
 259               break;
 260             good_sections++;
 261           }
 262           break;
 263
 264         case CORE_DATA:
 265         case CORE_STACK:
 266         case CORE_TEXT:
 267         case CORE_MMF:
 268         case CORE_SHM:
 269         case CORE_ANON_SHMEM:
 270           if (!make_bfd_asection (abfd, ".data",
 271                                   SEC_ALLOC + SEC_LOAD + SEC_HAS_CONTENTS,
 272                                   core_header.len,
 273                                   (bfd_vma) core_header.addr, 2))
 274             goto fail;
 275
 276           bfd_seek (abfd, (file_ptr) core_header.len, SEEK_CUR);
 277           good_sections++;
 278           break;
 279
 280         case CORE_NONE:
 281           /* Let's not punt if we encounter a section of unknown
 282              type.  Rather, let's make a note of it.  If we later
 283              see that there were also "good" sections, then we'll
 284              declare that this a core file, but we'll also warn that
 285              it may be incompatible with this gdb.
 286              */
 287           unknown_sections++;
 288           break;
 289
 290          default:
 291            goto fail; /*unrecognized core file type */
 292         }
 293     }
 294
 295   /* OK, we believe you.  You're a core file (sure, sure).  */
 296
 297   /* On HP/UX, we sometimes encounter core files where none of the threads
 298      was found to be the running thread (ie the signal was set to -1 for
 299      all threads).  This happens when the program was aborted externally
 300      via a TT_CORE ttrace system call.  In that case, we just pick one
 301      thread at random to be the active thread.  */
 302   if (core_kernel_thread_id (abfd) != 0
 303       && bfd_get_section_by_name (abfd, ".reg") == NULL)
 304     {
 305       asection *asect = bfd_sections_find_if (abfd, thread_section_p, NULL);
 306       asection *reg_sect;
 307
 308       if (asect != NULL)
 309         {
 310           reg_sect = make_bfd_asection (abfd, ".reg", asect->flags,
 311                                         asect->size, asect->vma,
 312                                         asect->alignment_power);
 313           if (reg_sect == NULL)
 314             goto fail;
 315
 316           reg_sect->filepos = asect->filepos;
 317         }
 318     }
 319
 320   /* Were there sections of unknown type?  If so, yet there were
 321      at least some complete sections of known type, then, issue
 322      a warning.  Possibly the core file was generated on a version
 323      of HP-UX that is incompatible with that for which this gdb was
 324      built.
 325      */
 326   if ((unknown_sections > 0) && (good_sections > 0))
 327     _bfd_error_handler
 328       ("%pB appears to be a core file,\nbut contains unknown sections."
 329        "  It may have been created on an incompatible\nversion of HP-UX."
 330        "  As a result, some information may be unavailable.\n",
 331        abfd);
 332
 333   return _bfd_no_cleanup;
 334
 335  fail:
 336   bfd_release (abfd, core_hdr (abfd));
 337   core_hdr (abfd) = NULL;
 338   bfd_section_list_clear (abfd);
 339   return NULL;
 340 }
 341
 342 static char *
 343 hpux_core_core_file_failing_command (bfd *abfd)
 344 {
 345   return core_command (abfd);
 346 }
 347
 348 static int
 349 hpux_core_core_file_failing_signal (bfd *abfd)
 350 {
 351   return core_signal (abfd);
 352 }
 353
 354 \f
 355 /* If somebody calls any byte-swapping routines, shoot them.  */
 356 static void
 357 swap_abort (void)
 358 {
 359   abort(); /* This way doesn't require any declaration for ANSI to fuck up */
 360 }
 361
 362 #define NO_GET ((bfd_vma (*) (const void *)) swap_abort)
 363 #define NO_PUT ((void (*) (bfd_vma, void *)) swap_abort)
 364 #define NO_GETS ((bfd_signed_vma (*) (const void *)) swap_abort)
 365 #define NO_GET64 ((bfd_uint64_t (*) (const void *)) swap_abort)
 366 #define NO_PUT64 ((void (*) (bfd_uint64_t, void *)) swap_abort)
 367 #define NO_GETS64 ((bfd_int64_t (*) (const void *)) swap_abort)
 368
 369 const bfd_target core_hpux_vec =
 370   {
 371     "hpux-core",
 372     bfd_target_unknown_flavour,
 373     BFD_ENDIAN_BIG,             /* target byte order */
 374     BFD_ENDIAN_BIG,             /* target headers byte order */
 375     (HAS_RELOC | EXEC_P |       /* object flags */
 376      HAS_LINENO | HAS_DEBUG |
 377      HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED),
 378     (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC), /* section flags */
 379     0,                          /* symbol prefix */
 380     ' ',                        /* ar_pad_char */
 381     16,                         /* ar_max_namelen */
 382     0,                          /* match priority.  */
 383     TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
 384     NO_GET64, NO_GETS64, NO_PUT64,      /* 64 bit data */
 385     NO_GET, NO_GETS, NO_PUT,            /* 32 bit data */
 386     NO_GET, NO_GETS, NO_PUT,            /* 16 bit data */
 387     NO_GET64, NO_GETS64, NO_PUT64,      /* 64 bit hdrs */
 388     NO_GET, NO_GETS, NO_PUT,            /* 32 bit hdrs */
 389     NO_GET, NO_GETS, NO_PUT,            /* 16 bit hdrs */
 390
 391     {                           /* bfd_check_format */
 392       _bfd_dummy_target,                /* unknown format */
 393       _bfd_dummy_target,                /* object file */
 394       _bfd_dummy_target,                /* archive */
 395       hpux_core_core_file_p             /* a core file */
 396     },
 397     {                           /* bfd_set_format */
 398       _bfd_bool_bfd_false_error,
 399       _bfd_bool_bfd_false_error,
 400       _bfd_bool_bfd_false_error,
 401       _bfd_bool_bfd_false_error
 402     },
 403     {                           /* bfd_write_contents */
 404       _bfd_bool_bfd_false_error,
 405       _bfd_bool_bfd_false_error,
 406       _bfd_bool_bfd_false_error,
 407       _bfd_bool_bfd_false_error
 408     },
 409
 410     BFD_JUMP_TABLE_GENERIC (_bfd_generic),
 411     BFD_JUMP_TABLE_COPY (_bfd_generic),
 412     BFD_JUMP_TABLE_CORE (hpux_core),
 413     BFD_JUMP_TABLE_ARCHIVE (_bfd_noarchive),
 414     BFD_JUMP_TABLE_SYMBOLS (_bfd_nosymbols),
 415     BFD_JUMP_TABLE_RELOCS (_bfd_norelocs),
 416     BFD_JUMP_TABLE_WRITE (_bfd_generic),
 417     BFD_JUMP_TABLE_LINK (_bfd_nolink),
 418     BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
 419
 420     NULL,
 421
 422     NULL                        /* backend_data */
 423   };