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Diffstat (limited to 'gdb/exec.c')
| -rw-r--r-- | gdb/exec.c | 762 |
1 files changed, 762 insertions, 0 deletions
diff --git a/gdb/exec.c b/gdb/exec.c new file mode 100644 index 0000000..87aed01 --- /dev/null +++ b/gdb/exec.c @@ -0,0 +1,762 @@ +/* Work with executable files, for GDB. + Copyright 1988, 1989, 1991, 1992, 1993, 1994, 1997, 1998 + 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ + +#include "defs.h" +#include "frame.h" +#include "inferior.h" +#include "target.h" +#include "gdbcmd.h" +#include "language.h" +#include "symfile.h" +#include "objfiles.h" + +#ifdef USG +#include <sys/types.h> +#endif + +#include <fcntl.h> +#include "gdb_string.h" + +#include "gdbcore.h" + +#include <ctype.h> +#include "gdb_stat.h" +#ifndef O_BINARY +#define O_BINARY 0 +#endif + +#include "xcoffsolib.h" + +struct vmap *map_vmap PARAMS ((bfd *, bfd *)); + +void (*file_changed_hook) PARAMS ((char *)); + +/* 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 *)); + +static void bfdsec_to_vmap PARAMS ((bfd *, sec_ptr, PTR)); + +static int ignore PARAMS ((CORE_ADDR, char *)); + +static void init_exec_ops PARAMS ((void)); + +void _initialize_exec PARAMS ((void)); + +extern int info_verbose; + +/* The target vector for executable files. */ + +struct target_ops exec_ops; + +/* 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 */ + +#ifndef NEED_TEXT_START_END +#define NEED_TEXT_START_END (0) +#endif +CORE_ADDR text_start = 0; +CORE_ADDR text_end = 0; + +struct vmap *vmap; + +/* ARGSUSED */ +static void +exec_close (quitting) + int quitting; +{ + int need_symtab_cleanup = 0; + struct vmap *vp, *nxt; + + for (nxt = vmap; nxt != NULL; ) + { + vp = nxt; + nxt = vp->nxt; + + /* if there is an objfile associated with this bfd, + free_objfile() will do proper cleanup of objfile *and* bfd. */ + + if (vp->objfile) + { + free_objfile (vp->objfile); + need_symtab_cleanup = 1; + } + else if (vp->bfd != exec_bfd) + /* FIXME-leak: We should be freeing vp->name too, I think. */ + if (!bfd_close (vp->bfd)) + warning ("cannot close \"%s\": %s", + vp->name, bfd_errmsg (bfd_get_error ())); + + /* FIXME: This routine is #if 0'd in symfile.c. What should we + be doing here? Should we just free everything in + vp->objfile->symtabs? Should free_objfile do that? + FIXME-as-well: free_objfile already free'd vp->name, so it isn't + valid here. */ + free_named_symtabs (vp->name); + free (vp); + } + + vmap = NULL; + + if (exec_bfd) + { + char *name = bfd_get_filename (exec_bfd); + + if (!bfd_close (exec_bfd)) + warning ("cannot close \"%s\": %s", + name, bfd_errmsg (bfd_get_error ())); + 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. + + This function is intended to be behave essentially the same + as exec_file_command, except that the latter will detect when + a target is being debugged, and will ask the user whether it + should be shut down first. (If the answer is "no", then the + new file is ignored.) + + This file is used by exec_file_command, to do the work of opening + and processing the exec file after any prompting has happened. + + And, it is used by child_attach, when the attach command was + given a pid but not a exec pathname, and the attach command could + figure out the pathname from the pid. (In this case, we shouldn't + ask the user whether the current target should be shut down -- + we're supplying the exec pathname late for good reason.) */ + +void +exec_file_attach (args, from_tty) + char *args; + int from_tty; +{ + char **argv; + char *filename; + + /* 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. */ + + argv = buildargv (args); + if (argv == NULL) + nomem (0); + + make_cleanup ((make_cleanup_func) 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 defined(__GO32__) || defined(_WIN32) + if (scratch_chan < 0) + { + char *exename = alloca (strlen (filename) + 5); + strcat (strcpy (exename, filename), ".exe"); + scratch_chan = openp (getenv ("PATH"), 1, exename, write_files ? + O_RDWR|O_BINARY : O_RDONLY|O_BINARY, 0, &scratch_pathname); + } +#endif + if (scratch_chan < 0) + perror_with_name (filename); + exec_bfd = bfd_fdopenr (scratch_pathname, gnutarget, scratch_chan); + + if (!exec_bfd) + error ("\"%s\": could not open as an executable file: %s", + scratch_pathname, bfd_errmsg (bfd_get_error ())); + + /* At this point, scratch_pathname and exec_bfd->name both point to the + same malloc'd string. However exec_close() will attempt to free it + via the exec_bfd->name pointer, so we need to make another copy and + leave exec_bfd as the new owner of the original copy. */ + scratch_pathname = strdup (scratch_pathname); + make_cleanup (free, scratch_pathname); + + if (!bfd_check_format (exec_bfd, bfd_object)) + { + /* Make sure to close exec_bfd, or else "run" might try to use + it. */ + exec_close (0); + error ("\"%s\": not in executable format: %s", + scratch_pathname, bfd_errmsg (bfd_get_error ())); + } + + /* FIXME - This should only be run for RS6000, but the ifdef is a poor + way to accomplish. */ +#ifdef IBM6000_TARGET + /* Setup initial vmap. */ + + map_vmap (exec_bfd, 0); + if (vmap == NULL) + { + /* Make sure to close exec_bfd, or else "run" might try to use + it. */ + exec_close (0); + error ("\"%s\": can't find the file sections: %s", + scratch_pathname, bfd_errmsg (bfd_get_error ())); + } +#endif /* IBM6000_TARGET */ + + if (build_section_table (exec_bfd, &exec_ops.to_sections, + &exec_ops.to_sections_end)) + { + /* Make sure to close exec_bfd, or else "run" might try to use + it. */ + exec_close (0); + error ("\"%s\": can't find the file sections: %s", + scratch_pathname, bfd_errmsg (bfd_get_error ())); + } + + /* text_end is sometimes used for where to put call dummies. A + few ports use these for other purposes too. */ + if (NEED_TEXT_START_END) + { + 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. */ + /* FIXME: The comment above does not match the code. The + code checks for sections with are either code *or* + readonly. */ + 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->the_bfd_section) + & (SEC_CODE | SEC_READONLY)) + { + if (text_start > p->addr) + text_start = p->addr; + if (text_end < p->endaddr) + text_end = p->endaddr; + } + } + + validate_files (); + + set_gdbarch_from_file (exec_bfd); + + 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_unfiltered ("No executable file now.\n"); +} + +/* 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); + + exec_file_attach (args, from_tty); +} + +/* 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); + if (file_changed_hook) + file_changed_hook (arg); +} + + +/* 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); + if (!(aflag & SEC_ALLOC)) + return; + if (0 == bfd_section_size (abfd, asect)) + return; + (*table_pp)->bfd = abfd; + (*table_pp)->the_bfd_section = 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; +} + +static void +bfdsec_to_vmap(abfd, sect, arg3) + bfd *abfd; + sec_ptr sect; + PTR arg3; +{ + struct vmap_and_bfd *vmap_bfd = (struct vmap_and_bfd *) arg3; + struct vmap *vp; + + vp = vmap_bfd->pvmap; + + if ((bfd_get_section_flags (abfd, sect) & SEC_LOAD) == 0) + return; + + if (STREQ (bfd_section_name (abfd, sect), ".text")) + { + vp->tstart = bfd_section_vma (abfd, sect); + vp->tend = vp->tstart + bfd_section_size (abfd, sect); + vp->tvma = bfd_section_vma (abfd, sect); + vp->toffs = sect->filepos; + } + else if (STREQ (bfd_section_name (abfd, sect), ".data")) + { + vp->dstart = bfd_section_vma (abfd, sect); + vp->dend = vp->dstart + bfd_section_size (abfd, sect); + vp->dvma = bfd_section_vma (abfd, sect); + } + /* Silently ignore other types of sections. (FIXME?) */ +} + +/* Make a vmap for ABFD which might be a member of the archive ARCH. + Return the new vmap. */ + +struct vmap * +map_vmap (abfd, arch) + bfd *abfd; + bfd *arch; +{ + struct vmap_and_bfd vmap_bfd; + struct vmap *vp, **vpp; + + vp = (struct vmap *) xmalloc (sizeof (*vp)); + memset ((char *) vp, '\0', sizeof (*vp)); + vp->nxt = 0; + vp->bfd = abfd; + vp->name = bfd_get_filename (arch ? arch : abfd); + vp->member = arch ? bfd_get_filename (abfd) : ""; + + vmap_bfd.pbfd = arch; + vmap_bfd.pvmap = vp; + bfd_map_over_sections (abfd, bfdsec_to_vmap, &vmap_bfd); + + /* Find the end of the list and append. */ + for (vpp = &vmap; *vpp; vpp = &(*vpp)->nxt) + ; + *vpp = vp; + + return vp; +} + +/* 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)); + asection *section; + + if (len <= 0) + abort(); + + if (overlay_debugging) + { + section = find_pc_overlay (memaddr); + if (pc_in_unmapped_range (memaddr, section)) + memaddr = overlay_mapped_address (memaddr, section); + } + + memend = memaddr + len; + xfer_fn = write ? bfd_set_section_contents : bfd_get_section_contents; + nextsectaddr = memend; + +#if 0 /* Stu's implementation */ +/* If a section has been specified, try to use it. Note that we cannot use the + specified section directly. This is because it usually comes from the + symbol file, which may be different from the exec or core file. Instead, we + have to lookup the specified section by name in the bfd associated with + to_sections. */ + + if (target_memory_bfd_section) + { + asection *s; + bfd *abfd; + asection *target_section; + bfd *target_bfd; + + s = target_memory_bfd_section; + abfd = s->owner; + + target_bfd = target->to_sections->bfd; + target_section = bfd_get_section_by_name (target_bfd, bfd_section_name (abfd, s)); + + if (target_section) + { + bfd_vma sec_addr; + bfd_size_type sec_size; + + sec_addr = bfd_section_vma (target_bfd, target_section); + sec_size = target_section->_raw_size; + + /* Make sure the requested memory starts inside the section. */ + + if (memaddr >= sec_addr + && memaddr < sec_addr + sec_size) + { + /* Cut back length in case request overflows the end of the section. */ + len = min (len, sec_addr + sec_size - memaddr); + + res = xfer_fn (target_bfd, target_section, myaddr, memaddr - sec_addr, len); + + return res ? len : 0; + } + } + } +#endif /* 0, Stu's implementation */ + for (p = target->to_sections; p < target->to_sections_end; p++) + { + if (overlay_debugging && section && p->the_bfd_section && + strcmp (section->name, p->the_bfd_section->name) != 0) + continue; /* not the section we need */ + if (memaddr >= p->addr) + if (memend <= p->endaddr) + { + /* Entire transfer is within this section. */ + res = xfer_fn (p->bfd, p->the_bfd_section, myaddr, + memaddr - p->addr, len); + return (res != 0) ? len : 0; + } + else if (memaddr >= p->endaddr) + { + /* 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->the_bfd_section, myaddr, + memaddr - p->addr, len); + return (res != 0) ? len : 0; + } + else + nextsectaddr = min (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)); + if (abfd == exec_bfd) + { + printf_filtered ("\tEntry point: "); + print_address_numeric (bfd_get_start_address (abfd), 1, gdb_stdout); + printf_filtered ("\n"); + } + for (p = t->to_sections; p < t->to_sections_end; p++) + { + /* FIXME-32x64 need a print_address_numeric with field width */ + 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->the_bfd_section->filepos, "08l")); + printf_filtered (" is %s", bfd_section_name (p->bfd, p->the_bfd_section)); + 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); + + if (vmap) + { + struct vmap *vp; + + printf_unfiltered ("\tMapping info for file `%s'.\n", vmap->name); + printf_unfiltered ("\t %8.8s %8.8s %8.8s %8.8s %8.8s %s\n", + "tstart", "tend", "dstart", "dend", "section", + "file(member)"); + + for (vp = vmap; vp; vp = vp->nxt) + printf_unfiltered ("\t0x%8.8x 0x%8.8x 0x%8.8x 0x%8.8x %s%s%s%s\n", + vp->tstart, vp->tend, vp->dstart, vp->dend, vp->name, + *vp->member ? "(" : "", vp->member, + *vp->member ? ")" : ""); + } +} + +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->the_bfd_section), seclen) + && bfd_section_name (exec_bfd, p->the_bfd_section)[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; +} + +/* Fill in the exec file target vector. Very few entries need to be + defined. */ + +void +init_exec_ops () +{ + exec_ops.to_shortname = "exec"; + exec_ops.to_longname = "Local exec file"; + exec_ops.to_doc = "Use an executable file as a target.\n\ +Specify the filename of the executable file."; + exec_ops.to_open = exec_file_command; + exec_ops.to_close = exec_close; + exec_ops.to_attach = find_default_attach; + exec_ops.to_require_attach = find_default_require_attach; + exec_ops.to_require_detach = find_default_require_detach; + exec_ops.to_xfer_memory = xfer_memory; + exec_ops.to_files_info = exec_files_info; + exec_ops.to_insert_breakpoint = ignore; + exec_ops.to_remove_breakpoint = ignore; + exec_ops.to_create_inferior = find_default_create_inferior; + exec_ops.to_clone_and_follow_inferior = find_default_clone_and_follow_inferior; + exec_ops.to_stratum = file_stratum; + exec_ops.to_has_memory = 1; + exec_ops.to_magic = OPS_MAGIC; +} + +void +_initialize_exec () +{ + struct cmd_list_element *c; + + init_exec_ops (); + + if (!dbx_commands) + { + 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); +} |