| 1 | /* Work with executable files, for GDB. |
| 2 | Copyright (C) 1988, 1989 Free Software Foundation, Inc. |
| 3 | |
| 4 | This file is part of GDB. |
| 5 | |
| 6 | GDB is free software; you can redistribute it and/or modify |
| 7 | it under the terms of the GNU General Public License as published by |
| 8 | the Free Software Foundation; either version 1, or (at your option) |
| 9 | any later version. |
| 10 | |
| 11 | GDB is distributed in the hope that it will be useful, |
| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | GNU General Public License for more details. |
| 15 | |
| 16 | You should have received a copy of the GNU General Public License |
| 17 | along with GDB; see the file COPYING. If not, write to |
| 18 | the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ |
| 19 | |
| 20 | #include <stdio.h> |
| 21 | #include "defs.h" |
| 22 | #include "param.h" |
| 23 | #include "frame.h" |
| 24 | #include "inferior.h" |
| 25 | #include "target.h" |
| 26 | |
| 27 | #ifdef USG |
| 28 | #include <sys/types.h> |
| 29 | #endif |
| 30 | |
| 31 | #include <sys/param.h> |
| 32 | #include <fcntl.h> |
| 33 | |
| 34 | #include "gdbcore.h" |
| 35 | |
| 36 | #ifdef STILL_NEEDED_FOR_DECSTATION |
| 37 | #include <sys/dir.h> /* For DECstations */ |
| 38 | #include <sys/user.h> /* After a.out.h */ |
| 39 | #include <sys/file.h> |
| 40 | #endif |
| 41 | |
| 42 | #include <ctype.h> |
| 43 | #include <sys/stat.h> |
| 44 | |
| 45 | extern char *getenv(); |
| 46 | extern void child_create_inferior (), child_attach (); |
| 47 | extern void add_syms_addr_command (); |
| 48 | extern void symbol_file_command (); |
| 49 | |
| 50 | /* The Binary File Descriptor handle for the executable file. */ |
| 51 | |
| 52 | bfd *exec_bfd = NULL; |
| 53 | |
| 54 | /* The base and bounds of the table of the exec file's sections. */ |
| 55 | |
| 56 | struct section_table *exec_sections, *exec_sections_end; |
| 57 | |
| 58 | /* Forward decl */ |
| 59 | |
| 60 | extern struct target_ops exec_ops; |
| 61 | |
| 62 | void |
| 63 | exec_close (quitting) |
| 64 | int quitting; |
| 65 | { |
| 66 | if (exec_bfd) { |
| 67 | bfd_close (exec_bfd); |
| 68 | exec_bfd = NULL; |
| 69 | } |
| 70 | } |
| 71 | |
| 72 | void |
| 73 | exec_file_command (filename, from_tty) |
| 74 | char *filename; |
| 75 | int from_tty; |
| 76 | { |
| 77 | target_preopen (from_tty); |
| 78 | |
| 79 | /* Remove any previous exec file. */ |
| 80 | unpush_target (&exec_ops); |
| 81 | |
| 82 | /* Now open and digest the file the user requested, if any. */ |
| 83 | |
| 84 | if (filename) |
| 85 | { |
| 86 | char *scratch_pathname; |
| 87 | int scratch_chan; |
| 88 | |
| 89 | filename = tilde_expand (filename); |
| 90 | make_cleanup (free, filename); |
| 91 | |
| 92 | /* FIXME, if writeable is set, open for read/write. */ |
| 93 | scratch_chan = openp (getenv ("PATH"), 1, filename, O_RDONLY, 0, |
| 94 | &scratch_pathname); |
| 95 | if (scratch_chan < 0) |
| 96 | perror_with_name (filename); |
| 97 | |
| 98 | exec_bfd = bfd_fdopenr (scratch_pathname, NULL, scratch_chan); |
| 99 | if (!exec_bfd) |
| 100 | error ("Could not open `%s' as an executable file: %s", |
| 101 | scratch_pathname, bfd_errmsg (bfd_error)); |
| 102 | if (!bfd_check_format (exec_bfd, bfd_object)) |
| 103 | error ("\"%s\": not in executable format: %s.", |
| 104 | scratch_pathname, bfd_errmsg (bfd_error)); |
| 105 | |
| 106 | #if FIXME |
| 107 | /* This code needs to be incorporated into BFD */ |
| 108 | #ifdef COFF_ENCAPSULATE |
| 109 | /* If we have a coff header, it can give us better values for |
| 110 | text_start and exec_data_start. This is particularly useful |
| 111 | for remote debugging of embedded systems. */ |
| 112 | if (N_FLAGS(exec_aouthdr) & N_FLAGS_COFF_ENCAPSULATE) |
| 113 | { |
| 114 | struct coffheader ch; |
| 115 | int val; |
| 116 | val = lseek (execchan, -(sizeof (AOUTHDR) + sizeof (ch)), 1); |
| 117 | if (val == -1) |
| 118 | perror_with_name (filename); |
| 119 | val = myread (execchan, &ch, sizeof (ch)); |
| 120 | if (val < 0) |
| 121 | perror_with_name (filename); |
| 122 | text_start = ch.text_start; |
| 123 | exec_data_start = ch.data_start; |
| 124 | } else |
| 125 | #endif |
| 126 | { |
| 127 | text_start = |
| 128 | IS_OBJECT_FILE (exec_aouthdr) ? 0 : N_TXTADDR (exec_aouthdr); |
| 129 | exec_data_start = IS_OBJECT_FILE (exec_aouthdr) |
| 130 | ? exec_aouthdr.a_text : N_DATADDR (exec_aouthdr); |
| 131 | } |
| 132 | #endif FIXME |
| 133 | |
| 134 | if (build_section_table (exec_bfd, &exec_sections, &exec_sections_end)) |
| 135 | error ("Can't find the file sections in `%s': %s", |
| 136 | exec_bfd->filename, bfd_errmsg (bfd_error)); |
| 137 | |
| 138 | validate_files (); |
| 139 | |
| 140 | push_target (&exec_ops); |
| 141 | |
| 142 | /* Tell display code (if any) about the changed file name. */ |
| 143 | if (exec_file_display_hook) |
| 144 | (*exec_file_display_hook) (filename); |
| 145 | } |
| 146 | else if (from_tty) |
| 147 | printf ("No exec file now.\n"); |
| 148 | } |
| 149 | |
| 150 | /* Set both the exec file and the symbol file, in one command. |
| 151 | What a novelty. Why did GDB go through four major releases before this |
| 152 | command was added? */ |
| 153 | |
| 154 | void |
| 155 | file_command (arg, from_tty) |
| 156 | char *arg; |
| 157 | int from_tty; |
| 158 | { |
| 159 | /* FIXME, if we lose on reading the symbol file, we should revert |
| 160 | the exec file, but that's rough. */ |
| 161 | exec_file_command (arg, from_tty); |
| 162 | symbol_file_command (arg, from_tty); |
| 163 | } |
| 164 | |
| 165 | \f |
| 166 | /* Locate all mappable sections of a BFD file. */ |
| 167 | |
| 168 | void |
| 169 | add_to_section_table (abfd, asect, table_pp) |
| 170 | bfd *abfd; |
| 171 | sec_ptr asect; |
| 172 | struct section_table **table_pp; |
| 173 | { |
| 174 | flagword aflag; |
| 175 | |
| 176 | aflag = bfd_get_section_flags (abfd, asect); |
| 177 | /* FIXME, we need to handle BSS segment here...it alloc's but doesn't load */ |
| 178 | if (!(aflag & SEC_LOAD)) |
| 179 | return; |
| 180 | (*table_pp)->sec_ptr = asect; |
| 181 | (*table_pp)->addr = bfd_section_vma (abfd, asect); |
| 182 | (*table_pp)->endaddr = (*table_pp)->addr + bfd_section_size (abfd, asect); |
| 183 | (*table_pp)++; |
| 184 | } |
| 185 | |
| 186 | int |
| 187 | build_section_table (some_bfd, start, end) |
| 188 | bfd *some_bfd; |
| 189 | struct section_table **start, **end; |
| 190 | { |
| 191 | unsigned count; |
| 192 | |
| 193 | count = bfd_count_sections (some_bfd); |
| 194 | if (count == 0) |
| 195 | abort(); /* return 1? */ |
| 196 | if (*start) |
| 197 | free (*start); |
| 198 | *start = (struct section_table *) xmalloc (count * sizeof (**start)); |
| 199 | *end = *start; |
| 200 | bfd_map_over_sections (some_bfd, add_to_section_table, end); |
| 201 | if (*end > *start + count) |
| 202 | abort(); |
| 203 | /* We could realloc the table, but it probably loses for most files. */ |
| 204 | return 0; |
| 205 | } |
| 206 | \f |
| 207 | /* Read or write the exec file. |
| 208 | |
| 209 | Args are address within exec file, address within gdb address-space, |
| 210 | length, and a flag indicating whether to read or write. |
| 211 | |
| 212 | Result is a length: |
| 213 | |
| 214 | 0: We cannot handle this address and length. |
| 215 | > 0: We have handled N bytes starting at this address. |
| 216 | (If N == length, we did it all.) We might be able |
| 217 | to handle more bytes beyond this length, but no |
| 218 | promises. |
| 219 | < 0: We cannot handle this address, but if somebody |
| 220 | else handles (-N) bytes, we can start from there. |
| 221 | |
| 222 | The same routine is used to handle both core and exec files; |
| 223 | we just tail-call it with more arguments to select between them. */ |
| 224 | |
| 225 | int |
| 226 | xfer_memory (memaddr, myaddr, len, write, abfd, sections, sections_end) |
| 227 | CORE_ADDR memaddr; |
| 228 | char *myaddr; |
| 229 | int len; |
| 230 | int write; |
| 231 | bfd *abfd; |
| 232 | struct section_table *sections, *sections_end; |
| 233 | { |
| 234 | boolean res; |
| 235 | struct section_table *p; |
| 236 | CORE_ADDR nextsectaddr, memend; |
| 237 | boolean (*xfer_fn) (); |
| 238 | |
| 239 | if (len <= 0) |
| 240 | abort(); |
| 241 | |
| 242 | memend = memaddr + len; |
| 243 | xfer_fn = write? bfd_set_section_contents: bfd_get_section_contents; |
| 244 | nextsectaddr = memend; |
| 245 | |
| 246 | for (p = sections; p < sections_end; p++) |
| 247 | { |
| 248 | if (p->addr <= memaddr) |
| 249 | if (p->endaddr >= memend) |
| 250 | { |
| 251 | /* Entire transfer is within this section. */ |
| 252 | res = xfer_fn (abfd, p->sec_ptr, myaddr, memaddr - p->addr, len); |
| 253 | return (res != false)? len: 0; |
| 254 | } |
| 255 | else if (p->endaddr <= memaddr) |
| 256 | { |
| 257 | /* This section ends before the transfer starts. */ |
| 258 | continue; |
| 259 | } |
| 260 | else |
| 261 | { |
| 262 | /* This section overlaps the transfer. Just do half. */ |
| 263 | len = p->endaddr - memaddr; |
| 264 | res = xfer_fn (abfd, p->sec_ptr, myaddr, memaddr - p->addr, len); |
| 265 | return (res != false)? len: 0; |
| 266 | } |
| 267 | else if (p->addr < nextsectaddr) |
| 268 | nextsectaddr = p->addr; |
| 269 | } |
| 270 | |
| 271 | if (nextsectaddr >= memend) |
| 272 | return 0; /* We can't help */ |
| 273 | else |
| 274 | return - (nextsectaddr - memaddr); /* Next boundary where we can help */ |
| 275 | } |
| 276 | |
| 277 | /* The function called by target_xfer_memory via our target_ops */ |
| 278 | |
| 279 | int |
| 280 | exec_xfer_memory (memaddr, myaddr, len, write) |
| 281 | CORE_ADDR memaddr; |
| 282 | char *myaddr; |
| 283 | int len; |
| 284 | int write; |
| 285 | { |
| 286 | return xfer_memory (memaddr, myaddr, len, write, |
| 287 | exec_bfd, exec_sections, exec_sections_end); |
| 288 | } |
| 289 | |
| 290 | |
| 291 | #ifdef FIXME |
| 292 | #ifdef REG_STACK_SEGMENT |
| 293 | /* MOVE TO BFD... */ |
| 294 | /* Pyramids and AM29000s have an extra segment in the virtual address space |
| 295 | for the (control) stack of register-window frames. The AM29000 folk |
| 296 | call it the "register stack" rather than the "memory stack". */ |
| 297 | else if (memaddr >= reg_stack_start && memaddr < reg_stack_end) |
| 298 | { |
| 299 | i = min (len, reg_stack_end - memaddr); |
| 300 | fileptr = memaddr - reg_stack_start + reg_stack_offset; |
| 301 | wanna_xfer = coredata; |
| 302 | } |
| 303 | #endif /* REG_STACK_SEGMENT */ |
| 304 | #endif FIXME |
| 305 | \f |
| 306 | static void |
| 307 | exec_files_info () |
| 308 | { |
| 309 | struct section_table *p; |
| 310 | |
| 311 | printf ("\tExecutable file `%s'.\n", bfd_get_filename(exec_bfd)); |
| 312 | |
| 313 | for (p = exec_sections; p < exec_sections_end; p++) |
| 314 | printf("\texecutable from 0x%08x to 0x%08x is %s\n", |
| 315 | p->addr, p->endaddr, |
| 316 | bfd_section_name (exec_bfd, p->sec_ptr)); |
| 317 | } |
| 318 | |
| 319 | static void |
| 320 | set_section_command (args, from_tty) |
| 321 | char *args; |
| 322 | int from_tty; |
| 323 | { |
| 324 | struct section_table *p; |
| 325 | char *secname; |
| 326 | unsigned seclen; |
| 327 | unsigned long secaddr; |
| 328 | char secprint[100]; |
| 329 | long offset; |
| 330 | |
| 331 | if (args == 0) |
| 332 | error ("Must specify section name and its virtual address"); |
| 333 | |
| 334 | /* Parse out section name */ |
| 335 | for (secname = args; !isspace(*args); args++) ; |
| 336 | seclen = args - secname; |
| 337 | |
| 338 | /* Parse out new virtual address */ |
| 339 | secaddr = parse_and_eval_address (args); |
| 340 | |
| 341 | for (p = exec_sections; p < exec_sections_end; p++) { |
| 342 | if (!strncmp (secname, bfd_section_name (exec_bfd, p->sec_ptr), seclen) |
| 343 | && bfd_section_name (exec_bfd, p->sec_ptr)[seclen] == '\0') { |
| 344 | offset = secaddr - p->addr; |
| 345 | p->addr += offset; |
| 346 | p->endaddr += offset; |
| 347 | exec_files_info(); |
| 348 | return; |
| 349 | } |
| 350 | } |
| 351 | if (seclen >= sizeof (secprint)) |
| 352 | seclen = sizeof (secprint) - 1; |
| 353 | strncpy (secprint, secname, seclen); |
| 354 | secprint[seclen] = '\0'; |
| 355 | error ("Section %s not found", secprint); |
| 356 | } |
| 357 | |
| 358 | struct target_ops exec_ops = { |
| 359 | "exec", "Local exec file", |
| 360 | "Use an executable file as a target.\n\ |
| 361 | Specify the filename of the executable file.", |
| 362 | exec_file_command, exec_close, /* open, close */ |
| 363 | child_attach, 0, 0, 0, /* attach, detach, resume, wait, */ |
| 364 | 0, 0, /* fetch_registers, store_registers, */ |
| 365 | 0, 0, 0, /* prepare_to_store, conv_to, conv_from, */ |
| 366 | exec_xfer_memory, exec_files_info, |
| 367 | 0, 0, /* insert_breakpoint, remove_breakpoint, */ |
| 368 | 0, 0, 0, 0, 0, /* terminal stuff */ |
| 369 | 0, 0, /* kill, load */ |
| 370 | add_syms_addr_command, |
| 371 | 0, 0, /* call fn, lookup sym */ |
| 372 | child_create_inferior, |
| 373 | 0, /* mourn_inferior */ |
| 374 | file_stratum, 0, /* next */ |
| 375 | 0, 1, 0, 0, 0, /* all mem, mem, stack, regs, exec */ |
| 376 | OPS_MAGIC, /* Always the last thing */ |
| 377 | }; |
| 378 | |
| 379 | void |
| 380 | _initialize_exec() |
| 381 | { |
| 382 | |
| 383 | add_com ("file", class_files, file_command, |
| 384 | "Use FILE as program to be debugged.\n\ |
| 385 | It is read for its symbols, for getting the contents of pure memory,\n\ |
| 386 | and it is the program executed when you use the `run' command.\n\ |
| 387 | If FILE cannot be found as specified, your execution directory path\n\ |
| 388 | ($PATH) is searched for a command of that name.\n\ |
| 389 | No arg means to have no executable file and no symbols."); |
| 390 | |
| 391 | add_com ("exec-file", class_files, exec_file_command, |
| 392 | "Use FILE as program for getting contents of pure memory.\n\ |
| 393 | If FILE cannot be found as specified, your execution directory path\n\ |
| 394 | is searched for a command of that name.\n\ |
| 395 | No arg means have no executable file."); |
| 396 | |
| 397 | add_com ("section", class_files, set_section_command, |
| 398 | "Change the base address of section SECTION of the exec file to ADDR.\n\ |
| 399 | This can be used if the exec file does not contain section addresses,\n\ |
| 400 | (such as in the a.out format), or when the addresses specified in the\n\ |
| 401 | file itself are wrong. Each section must be changed separately. The\n\ |
| 402 | ``info files'' command lists all the sections and their addresses."); |
| 403 | |
| 404 | add_target (&exec_ops); |
| 405 | } |