diff options
Diffstat (limited to 'gnu/usr.bin/gdb/gdb/exec.c')
-rw-r--r-- | gnu/usr.bin/gdb/gdb/exec.c | 489 |
1 files changed, 489 insertions, 0 deletions
diff --git a/gnu/usr.bin/gdb/gdb/exec.c b/gnu/usr.bin/gdb/gdb/exec.c new file mode 100644 index 0000000..f66a33c --- /dev/null +++ b/gnu/usr.bin/gdb/gdb/exec.c @@ -0,0 +1,489 @@ +/* Work with executable files, for GDB. + Copyright 1988, 1989, 1991, 1992 Free Software Foundation, Inc. + +This file is part of GDB. + +This program is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2 of the License, or +(at your option) any later version. + +This program is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +You should have received a copy of the GNU General Public License +along with this program; if not, write to the Free Software +Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ + +#include "defs.h" +#include "frame.h" +#include "inferior.h" +#include "target.h" +#include "gdbcmd.h" + +#ifdef USG +#include <sys/types.h> +#endif + +#include <sys/param.h> +#include <fcntl.h> +#include <string.h> + +#include "gdbcore.h" + +#include <ctype.h> +#include <sys/stat.h> +#ifndef O_BINARY +#define O_BINARY 0 +#endif + +/* Prototypes for local functions */ + +static void +add_to_section_table PARAMS ((bfd *, sec_ptr, PTR)); + +static void +exec_close PARAMS ((int)); + +static void +file_command PARAMS ((char *, int)); + +static void +set_section_command PARAMS ((char *, int)); + +static void +exec_files_info PARAMS ((struct target_ops *)); + +extern int info_verbose; + +/* The Binary File Descriptor handle for the executable file. */ + +bfd *exec_bfd = NULL; + +/* Whether to open exec and core files read-only or read-write. */ + +int write_files = 0; + +/* Text start and end addresses (KLUDGE) if needed */ + +#ifdef NEED_TEXT_START_END +CORE_ADDR text_start = 0; +CORE_ADDR text_end = 0; +#endif + +/* Forward decl */ + +extern struct target_ops exec_ops; + +/* ARGSUSED */ +static void +exec_close (quitting) + int quitting; +{ + if (exec_bfd) { + char *name = bfd_get_filename (exec_bfd); + bfd_close (exec_bfd); + free (name); + exec_bfd = NULL; + } + if (exec_ops.to_sections) { + free ((PTR)exec_ops.to_sections); + exec_ops.to_sections = NULL; + exec_ops.to_sections_end = NULL; + } +} + +/* Process the first arg in ARGS as the new exec file. + + Note that we have to explicitly ignore additional args, since we can + be called from file_command(), which also calls symbol_file_command() + which can take multiple args. */ + +void +exec_file_command (args, from_tty) + char *args; + int from_tty; +{ + char **argv; + char *filename; + + target_preopen (from_tty); + + /* Remove any previous exec file. */ + unpush_target (&exec_ops); + + /* Now open and digest the file the user requested, if any. */ + + if (args) + { + char *scratch_pathname; + int scratch_chan; + + /* Scan through the args and pick up the first non option arg + as the filename. */ + + if ((argv = buildargv (args)) == NULL) + { + nomem (0); + } + make_cleanup (freeargv, (char *) argv); + + for (; (*argv != NULL) && (**argv == '-'); argv++) {;} + if (*argv == NULL) + { + error ("no exec file name was specified"); + } + + filename = tilde_expand (*argv); + make_cleanup (free, filename); + + scratch_chan = openp (getenv ("PATH"), 1, filename, + write_files? O_RDWR|O_BINARY: O_RDONLY|O_BINARY, 0, + &scratch_pathname); + if (scratch_chan < 0) + perror_with_name (filename); + + exec_bfd = bfd_fdopenr (scratch_pathname, gnutarget, scratch_chan); + if (!exec_bfd) + error ("Could not open `%s' as an executable file: %s", + scratch_pathname, bfd_errmsg (bfd_error)); + if (!bfd_check_format (exec_bfd, bfd_object)) + error ("\"%s\": not in executable format: %s.", + scratch_pathname, bfd_errmsg (bfd_error)); + + if (build_section_table (exec_bfd, &exec_ops.to_sections, + &exec_ops.to_sections_end)) + error ("Can't find the file sections in `%s': %s", + exec_bfd->filename, bfd_errmsg (bfd_error)); + +#ifdef NEED_TEXT_START_END + + /* text_end is sometimes used for where to put call dummies. A + few ports use these for other purposes too. */ + + { + struct section_table *p; + + /* Set text_start to the lowest address of the start of any + readonly code section and set text_end to the highest + address of the end of any readonly code section. */ + + text_start = ~(CORE_ADDR)0; + text_end = (CORE_ADDR)0; + for (p = exec_ops.to_sections; p < exec_ops.to_sections_end; p++) + if (bfd_get_section_flags (p->bfd, p->sec_ptr) + & (SEC_CODE | SEC_READONLY)) + { + if (text_start > p->addr) + text_start = p->addr; + if (text_end < p->endaddr) + text_end = p->endaddr; + } + } +#endif + + validate_files (); + + push_target (&exec_ops); + + /* Tell display code (if any) about the changed file name. */ + if (exec_file_display_hook) + (*exec_file_display_hook) (filename); + } + else if (from_tty) + printf ("No exec file now.\n"); +} + +/* Set both the exec file and the symbol file, in one command. + What a novelty. Why did GDB go through four major releases before this + command was added? */ + +static void +file_command (arg, from_tty) + char *arg; + int from_tty; +{ + /* FIXME, if we lose on reading the symbol file, we should revert + the exec file, but that's rough. */ + exec_file_command (arg, from_tty); + symbol_file_command (arg, from_tty); +} + + +/* Locate all mappable sections of a BFD file. + table_pp_char is a char * to get it through bfd_map_over_sections; + we cast it back to its proper type. */ + +static void +add_to_section_table (abfd, asect, table_pp_char) + bfd *abfd; + sec_ptr asect; + PTR table_pp_char; +{ + struct section_table **table_pp = (struct section_table **)table_pp_char; + flagword aflag; + + aflag = bfd_get_section_flags (abfd, asect); + /* FIXME, we need to handle BSS segment here...it alloc's but doesn't load */ + if (!(aflag & SEC_LOAD)) + return; + if (0 == bfd_section_size (abfd, asect)) + return; + (*table_pp)->bfd = abfd; + (*table_pp)->sec_ptr = asect; + (*table_pp)->addr = bfd_section_vma (abfd, asect); + (*table_pp)->endaddr = (*table_pp)->addr + bfd_section_size (abfd, asect); + (*table_pp)++; +} + +/* Builds a section table, given args BFD, SECTABLE_PTR, SECEND_PTR. + Returns 0 if OK, 1 on error. */ + +int +build_section_table (some_bfd, start, end) + bfd *some_bfd; + struct section_table **start, **end; +{ + unsigned count; + + count = bfd_count_sections (some_bfd); + if (*start) + free ((PTR)*start); + *start = (struct section_table *) xmalloc (count * sizeof (**start)); + *end = *start; + bfd_map_over_sections (some_bfd, add_to_section_table, (char *)end); + if (*end > *start + count) + abort(); + /* We could realloc the table, but it probably loses for most files. */ + return 0; +} + +/* Read or write the exec file. + + Args are address within a BFD file, address within gdb address-space, + length, and a flag indicating whether to read or write. + + Result is a length: + + 0: We cannot handle this address and length. + > 0: We have handled N bytes starting at this address. + (If N == length, we did it all.) We might be able + to handle more bytes beyond this length, but no + promises. + < 0: We cannot handle this address, but if somebody + else handles (-N) bytes, we can start from there. + + The same routine is used to handle both core and exec files; + we just tail-call it with more arguments to select between them. */ + +int +xfer_memory (memaddr, myaddr, len, write, target) + CORE_ADDR memaddr; + char *myaddr; + int len; + int write; + struct target_ops *target; +{ + boolean res; + struct section_table *p; + CORE_ADDR nextsectaddr, memend; + boolean (*xfer_fn) PARAMS ((bfd *, sec_ptr, PTR, file_ptr, bfd_size_type)); + + if (len <= 0) + abort(); + + memend = memaddr + len; + xfer_fn = write? bfd_set_section_contents: bfd_get_section_contents; + nextsectaddr = memend; + + for (p = target->to_sections; p < target->to_sections_end; p++) + { + if (p->addr <= memaddr) + if (p->endaddr >= memend) + { + /* Entire transfer is within this section. */ + res = xfer_fn (p->bfd, p->sec_ptr, myaddr, memaddr - p->addr, len); + return (res != false)? len: 0; + } + else if (p->endaddr <= memaddr) + { + /* This section ends before the transfer starts. */ + continue; + } + else + { + /* This section overlaps the transfer. Just do half. */ + len = p->endaddr - memaddr; + res = xfer_fn (p->bfd, p->sec_ptr, myaddr, memaddr - p->addr, len); + return (res != false)? len: 0; + } + else if (p->addr < nextsectaddr) + nextsectaddr = p->addr; + } + + if (nextsectaddr >= memend) + return 0; /* We can't help */ + else + return - (nextsectaddr - memaddr); /* Next boundary where we can help */ +} + +#ifdef FIXME +#ifdef REG_STACK_SEGMENT +/* MOVE TO BFD... */ + /* Pyramids and AM29000s have an extra segment in the virtual address space + for the (control) stack of register-window frames. The AM29000 folk + call it the "register stack" rather than the "memory stack". */ + else if (memaddr >= reg_stack_start && memaddr < reg_stack_end) + { + i = min (len, reg_stack_end - memaddr); + fileptr = memaddr - reg_stack_start + reg_stack_offset; + wanna_xfer = coredata; + } +#endif /* REG_STACK_SEGMENT */ +#endif /* FIXME */ + +void +print_section_info (t, abfd) + struct target_ops *t; + bfd *abfd; +{ + struct section_table *p; + + printf_filtered ("\t`%s', ", bfd_get_filename(abfd)); + wrap_here (" "); + printf_filtered ("file type %s.\n", bfd_get_target(abfd)); + printf_filtered ("\tEntry point: %s\n", + local_hex_string ((unsigned long) bfd_get_start_address (exec_bfd))); + for (p = t->to_sections; p < t->to_sections_end; p++) { + printf_filtered ("\t%s", local_hex_string_custom ((unsigned long) p->addr, "08l")); + printf_filtered (" - %s", local_hex_string_custom ((unsigned long) p->endaddr, "08l")); + if (info_verbose) + printf_filtered (" @ %s", + local_hex_string_custom ((unsigned long) p->sec_ptr->filepos, "08l")); + printf_filtered (" is %s", bfd_section_name (p->bfd, p->sec_ptr)); + if (p->bfd != abfd) { + printf_filtered (" in %s", bfd_get_filename (p->bfd)); + } + printf_filtered ("\n"); + } +} + +static void +exec_files_info (t) + struct target_ops *t; +{ + print_section_info (t, exec_bfd); +} + +static void +set_section_command (args, from_tty) + char *args; + int from_tty; +{ + struct section_table *p; + char *secname; + unsigned seclen; + unsigned long secaddr; + char secprint[100]; + long offset; + + if (args == 0) + error ("Must specify section name and its virtual address"); + + /* Parse out section name */ + for (secname = args; !isspace(*args); args++) ; + seclen = args - secname; + + /* Parse out new virtual address */ + secaddr = parse_and_eval_address (args); + + for (p = exec_ops.to_sections; p < exec_ops.to_sections_end; p++) { + if (!strncmp (secname, bfd_section_name (exec_bfd, p->sec_ptr), seclen) + && bfd_section_name (exec_bfd, p->sec_ptr)[seclen] == '\0') { + offset = secaddr - p->addr; + p->addr += offset; + p->endaddr += offset; + if (from_tty) + exec_files_info(&exec_ops); + return; + } + } + if (seclen >= sizeof (secprint)) + seclen = sizeof (secprint) - 1; + strncpy (secprint, secname, seclen); + secprint[seclen] = '\0'; + error ("Section %s not found", secprint); +} + +/* If mourn is being called in all the right places, this could be say + `gdb internal error' (since generic_mourn calls breakpoint_init_inferior). */ + +static int +ignore (addr, contents) + CORE_ADDR addr; + char *contents; +{ + return 0; +} + +struct target_ops exec_ops = { + "exec", "Local exec file", + "Use an executable file as a target.\n\ +Specify the filename of the executable file.", + exec_file_command, exec_close, /* open, close */ + find_default_attach, 0, 0, 0, /* attach, detach, resume, wait, */ + 0, 0, /* fetch_registers, store_registers, */ + 0, /* prepare_to_store, */ + xfer_memory, exec_files_info, + ignore, ignore, /* insert_breakpoint, remove_breakpoint, */ + 0, 0, 0, 0, 0, /* terminal stuff */ + 0, 0, /* kill, load */ + 0, /* lookup sym */ + find_default_create_inferior, + 0, /* mourn_inferior */ + 0, /* can_run */ + 0, /* notice_signals */ + file_stratum, 0, /* next */ + 0, 1, 0, 0, 0, /* all mem, mem, stack, regs, exec */ + 0, 0, /* section pointers */ + OPS_MAGIC, /* Always the last thing */ +}; + +void +_initialize_exec() +{ + struct cmd_list_element *c; + + c = add_cmd ("file", class_files, file_command, + "Use FILE as program to be debugged.\n\ +It is read for its symbols, for getting the contents of pure memory,\n\ +and it is the program executed when you use the `run' command.\n\ +If FILE cannot be found as specified, your execution directory path\n\ +($PATH) is searched for a command of that name.\n\ +No arg means to have no executable file and no symbols.", &cmdlist); + c->completer = filename_completer; + + c = add_cmd ("exec-file", class_files, exec_file_command, + "Use FILE as program for getting contents of pure memory.\n\ +If FILE cannot be found as specified, your execution directory path\n\ +is searched for a command of that name.\n\ +No arg means have no executable file.", &cmdlist); + c->completer = filename_completer; + + add_com ("section", class_files, set_section_command, + "Change the base address of section SECTION of the exec file to ADDR.\n\ +This can be used if the exec file does not contain section addresses,\n\ +(such as in the a.out format), or when the addresses specified in the\n\ +file itself are wrong. Each section must be changed separately. The\n\ +``info files'' command lists all the sections and their addresses."); + + add_show_from_set + (add_set_cmd ("write", class_support, var_boolean, (char *)&write_files, + "Set writing into executable and core files.", + &setlist), + &showlist); + + add_target (&exec_ops); +} |