609 lines
18 KiB
C
609 lines
18 KiB
C
/* GNU/Linux specific methods for using the /proc file system.
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Copyright 2001, 2002 Free Software Foundation, Inc.
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This file is part of GDB.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 59 Temple Place - Suite 330,
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Boston, MA 02111-1307, USA. */
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#include "defs.h"
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#include "inferior.h"
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#include <sys/param.h> /* for MAXPATHLEN */
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#include <sys/procfs.h> /* for elf_gregset etc. */
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#include "gdb_stat.h" /* for struct stat */
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#include <ctype.h> /* for isdigit */
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#include <unistd.h> /* for open, pread64 */
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#include <fcntl.h> /* for O_RDONLY */
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#include "regcache.h" /* for registers_changed */
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#include "gregset.h" /* for gregset */
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#include "gdbcore.h" /* for get_exec_file */
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#include "gdbthread.h" /* for struct thread_info etc. */
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#include "elf-bfd.h" /* for elfcore_write_* */
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#include "cli/cli-decode.h" /* for add_info */
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#include "gdb_string.h"
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#ifndef O_LARGEFILE
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#define O_LARGEFILE 0
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#endif
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/* Function: child_pid_to_exec_file
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*
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* Accepts an integer pid
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* Returns a string representing a file that can be opened
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* to get the symbols for the child process.
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*/
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char *
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child_pid_to_exec_file (int pid)
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{
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char *name1, *name2;
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name1 = xmalloc (MAXPATHLEN);
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name2 = xmalloc (MAXPATHLEN);
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make_cleanup (xfree, name1);
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make_cleanup (xfree, name2);
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memset (name2, 0, MAXPATHLEN);
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sprintf (name1, "/proc/%d/exe", pid);
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if (readlink (name1, name2, MAXPATHLEN) > 0)
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return name2;
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else
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return name1;
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}
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/* Function: read_mappings
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*
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* Service function for corefiles and info proc.
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*/
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static int
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read_mapping (FILE *mapfile,
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long long *addr,
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long long *endaddr,
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char *permissions,
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long long *offset,
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char *device, long long *inode, char *filename)
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{
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int ret = fscanf (mapfile, "%llx-%llx %s %llx %s %llx",
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addr, endaddr, permissions, offset, device, inode);
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if (ret > 0 && ret != EOF && *inode != 0)
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{
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/* Eat everything up to EOL for the filename. This will prevent
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weird filenames (such as one with embedded whitespace) from
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confusing this code. It also makes this code more robust
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in respect to annotations the kernel may add after the
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filename.
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Note the filename is used for informational purposes only. */
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ret += fscanf (mapfile, "%[^\n]\n", filename);
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}
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else
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{
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filename[0] = '\0'; /* no filename */
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fscanf (mapfile, "\n");
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}
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return (ret != 0 && ret != EOF);
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}
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/* Function: linux_find_memory_regions
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*
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* Fills the "to_find_memory_regions" target vector.
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* Lists the memory regions in the inferior for a corefile.
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*/
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static int
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linux_find_memory_regions (int (*func) (CORE_ADDR,
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unsigned long,
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int, int, int, void *), void *obfd)
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{
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long long pid = PIDGET (inferior_ptid);
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char mapsfilename[MAXPATHLEN];
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FILE *mapsfile;
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long long addr, endaddr, size, offset, inode;
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char permissions[8], device[8], filename[MAXPATHLEN];
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int read, write, exec;
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int ret;
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/* Compose the filename for the /proc memory map, and open it. */
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sprintf (mapsfilename, "/proc/%lld/maps", pid);
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if ((mapsfile = fopen (mapsfilename, "r")) == NULL)
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error ("Could not open %s\n", mapsfilename);
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if (info_verbose)
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fprintf_filtered (gdb_stdout,
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"Reading memory regions from %s\n", mapsfilename);
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/* Now iterate until end-of-file. */
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while (read_mapping (mapsfile, &addr, &endaddr, &permissions[0],
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&offset, &device[0], &inode, &filename[0]))
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{
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size = endaddr - addr;
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/* Get the segment's permissions. */
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read = (strchr (permissions, 'r') != 0);
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write = (strchr (permissions, 'w') != 0);
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exec = (strchr (permissions, 'x') != 0);
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if (info_verbose)
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{
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fprintf_filtered (gdb_stdout,
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"Save segment, %lld bytes at 0x%s (%c%c%c)",
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size, paddr_nz (addr),
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read ? 'r' : ' ',
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write ? 'w' : ' ', exec ? 'x' : ' ');
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if (filename && filename[0])
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fprintf_filtered (gdb_stdout, " for %s", filename);
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fprintf_filtered (gdb_stdout, "\n");
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}
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/* Invoke the callback function to create the corefile segment. */
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func (addr, size, read, write, exec, obfd);
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}
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fclose (mapsfile);
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return 0;
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}
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/* Function: linux_do_thread_registers
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*
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* Records the thread's register state for the corefile note section.
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*/
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static char *
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linux_do_thread_registers (bfd *obfd, ptid_t ptid,
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char *note_data, int *note_size)
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{
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gdb_gregset_t gregs;
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gdb_fpregset_t fpregs;
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#ifdef FILL_FPXREGSET
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gdb_fpxregset_t fpxregs;
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#endif
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unsigned long merged_pid = ptid_get_tid (ptid) << 16 | ptid_get_pid (ptid);
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fill_gregset (&gregs, -1);
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note_data = (char *) elfcore_write_prstatus (obfd,
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note_data,
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note_size,
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merged_pid,
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stop_signal, &gregs);
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fill_fpregset (&fpregs, -1);
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note_data = (char *) elfcore_write_prfpreg (obfd,
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note_data,
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note_size,
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&fpregs, sizeof (fpregs));
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#ifdef FILL_FPXREGSET
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fill_fpxregset (&fpxregs, -1);
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note_data = (char *) elfcore_write_prxfpreg (obfd,
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note_data,
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note_size,
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&fpxregs, sizeof (fpxregs));
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#endif
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return note_data;
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}
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struct linux_corefile_thread_data
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{
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bfd *obfd;
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char *note_data;
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int *note_size;
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int num_notes;
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};
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/* Function: linux_corefile_thread_callback
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*
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* Called by gdbthread.c once per thread.
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* Records the thread's register state for the corefile note section.
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*/
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static int
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linux_corefile_thread_callback (struct thread_info *ti, void *data)
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{
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struct linux_corefile_thread_data *args = data;
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ptid_t saved_ptid = inferior_ptid;
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inferior_ptid = ti->ptid;
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registers_changed ();
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target_fetch_registers (-1); /* FIXME should not be necessary;
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fill_gregset should do it automatically. */
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args->note_data = linux_do_thread_registers (args->obfd,
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ti->ptid,
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args->note_data,
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args->note_size);
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args->num_notes++;
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inferior_ptid = saved_ptid;
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registers_changed ();
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target_fetch_registers (-1); /* FIXME should not be necessary;
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fill_gregset should do it automatically. */
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return 0;
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}
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/* Function: linux_make_note_section
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*
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* Fills the "to_make_corefile_note" target vector.
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* Builds the note section for a corefile, and returns it
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* in a malloc buffer.
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*/
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static char *
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linux_make_note_section (bfd *obfd, int *note_size)
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{
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struct linux_corefile_thread_data thread_args;
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struct cleanup *old_chain;
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char fname[16] = { '\0' };
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char psargs[80] = { '\0' };
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char *note_data = NULL;
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ptid_t current_ptid = inferior_ptid;
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if (get_exec_file (0))
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{
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strncpy (fname, strrchr (get_exec_file (0), '/') + 1, sizeof (fname));
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strncpy (psargs, get_exec_file (0), sizeof (psargs));
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if (get_inferior_args ())
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{
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strncat (psargs, " ", sizeof (psargs) - strlen (psargs));
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strncat (psargs, get_inferior_args (),
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sizeof (psargs) - strlen (psargs));
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}
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note_data = (char *) elfcore_write_prpsinfo (obfd,
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note_data,
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note_size, fname, psargs);
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}
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/* Dump information for threads. */
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thread_args.obfd = obfd;
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thread_args.note_data = note_data;
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thread_args.note_size = note_size;
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thread_args.num_notes = 0;
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iterate_over_threads (linux_corefile_thread_callback, &thread_args);
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if (thread_args.num_notes == 0)
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{
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/* iterate_over_threads didn't come up with any threads;
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just use inferior_ptid. */
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note_data = linux_do_thread_registers (obfd, inferior_ptid,
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note_data, note_size);
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}
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else
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{
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note_data = thread_args.note_data;
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}
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make_cleanup (xfree, note_data);
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return note_data;
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}
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/*
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* Function: linux_info_proc_cmd
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*
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* Implement the "info proc" command.
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*/
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static void
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linux_info_proc_cmd (char *args, int from_tty)
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{
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long long pid = PIDGET (inferior_ptid);
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FILE *procfile;
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char **argv = NULL;
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char buffer[MAXPATHLEN];
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char fname1[MAXPATHLEN], fname2[MAXPATHLEN];
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int cmdline_f = 1;
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int cwd_f = 1;
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int exe_f = 1;
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int mappings_f = 0;
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int environ_f = 0;
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int status_f = 0;
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int stat_f = 0;
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int all = 0;
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struct stat dummy;
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if (args)
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{
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/* Break up 'args' into an argv array. */
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if ((argv = buildargv (args)) == NULL)
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nomem (0);
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else
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make_cleanup_freeargv (argv);
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}
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while (argv != NULL && *argv != NULL)
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{
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if (isdigit (argv[0][0]))
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{
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pid = strtoul (argv[0], NULL, 10);
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}
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else if (strncmp (argv[0], "mappings", strlen (argv[0])) == 0)
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{
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mappings_f = 1;
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}
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else if (strcmp (argv[0], "status") == 0)
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{
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status_f = 1;
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}
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else if (strcmp (argv[0], "stat") == 0)
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{
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stat_f = 1;
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}
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else if (strcmp (argv[0], "cmd") == 0)
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{
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cmdline_f = 1;
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}
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else if (strncmp (argv[0], "exe", strlen (argv[0])) == 0)
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{
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exe_f = 1;
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}
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else if (strcmp (argv[0], "cwd") == 0)
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{
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cwd_f = 1;
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}
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else if (strncmp (argv[0], "all", strlen (argv[0])) == 0)
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{
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all = 1;
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}
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else
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{
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/* [...] (future options here) */
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}
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argv++;
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}
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if (pid == 0)
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error ("No current process: you must name one.");
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sprintf (fname1, "/proc/%lld", pid);
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if (stat (fname1, &dummy) != 0)
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error ("No /proc directory: '%s'", fname1);
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printf_filtered ("process %lld\n", pid);
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if (cmdline_f || all)
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{
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sprintf (fname1, "/proc/%lld/cmdline", pid);
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if ((procfile = fopen (fname1, "r")) > 0)
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{
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fgets (buffer, sizeof (buffer), procfile);
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printf_filtered ("cmdline = '%s'\n", buffer);
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fclose (procfile);
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}
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else
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warning ("unable to open /proc file '%s'", fname1);
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}
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if (cwd_f || all)
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{
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sprintf (fname1, "/proc/%lld/cwd", pid);
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memset (fname2, 0, sizeof (fname2));
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if (readlink (fname1, fname2, sizeof (fname2)) > 0)
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printf_filtered ("cwd = '%s'\n", fname2);
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else
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warning ("unable to read link '%s'", fname1);
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}
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if (exe_f || all)
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{
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sprintf (fname1, "/proc/%lld/exe", pid);
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memset (fname2, 0, sizeof (fname2));
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if (readlink (fname1, fname2, sizeof (fname2)) > 0)
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printf_filtered ("exe = '%s'\n", fname2);
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else
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warning ("unable to read link '%s'", fname1);
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}
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if (mappings_f || all)
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{
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sprintf (fname1, "/proc/%lld/maps", pid);
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if ((procfile = fopen (fname1, "r")) > 0)
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{
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long long addr, endaddr, size, offset, inode;
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char permissions[8], device[8], filename[MAXPATHLEN];
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char *header_fmt_string, *data_fmt_string;
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if (TARGET_ADDR_BIT == 32)
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{
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header_fmt_string = "\t%10s %10s %10s %10s %7s\n";
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data_fmt_string = "\t%#10lx %#10lx %#10x %#10x %7s\n";
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}
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else
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{
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header_fmt_string = " %18s %18s %10s %10s %7s\n";
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data_fmt_string = " %#18lx %#18lx %#10x %#10x %7s\n";
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}
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printf_filtered ("Mapped address spaces:\n\n");
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printf_filtered (header_fmt_string,
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"Start Addr",
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" End Addr",
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" Size", " Offset", "objfile");
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while (read_mapping (procfile, &addr, &endaddr, &permissions[0],
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&offset, &device[0], &inode, &filename[0]))
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{
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size = endaddr - addr;
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printf_filtered (data_fmt_string, (unsigned long) addr, /* FIXME: pr_addr */
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(unsigned long) endaddr,
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(int) size,
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(unsigned int) offset,
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filename[0] ? filename : "");
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}
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fclose (procfile);
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}
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else
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warning ("unable to open /proc file '%s'", fname1);
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}
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if (status_f || all)
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{
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sprintf (fname1, "/proc/%lld/status", pid);
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if ((procfile = fopen (fname1, "r")) > 0)
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{
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while (fgets (buffer, sizeof (buffer), procfile) != NULL)
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printf_filtered (buffer);
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fclose (procfile);
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}
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else
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warning ("unable to open /proc file '%s'", fname1);
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}
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if (stat_f || all)
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{
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sprintf (fname1, "/proc/%lld/stat", pid);
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if ((procfile = fopen (fname1, "r")) > 0)
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{
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int itmp;
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char ctmp;
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if (fscanf (procfile, "%d ", &itmp) > 0)
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printf_filtered ("Process: %d\n", itmp);
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if (fscanf (procfile, "%s ", &buffer[0]) > 0)
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printf_filtered ("Exec file: %s\n", buffer);
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if (fscanf (procfile, "%c ", &ctmp) > 0)
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printf_filtered ("State: %c\n", ctmp);
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if (fscanf (procfile, "%d ", &itmp) > 0)
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printf_filtered ("Parent process: %d\n", itmp);
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if (fscanf (procfile, "%d ", &itmp) > 0)
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printf_filtered ("Process group: %d\n", itmp);
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if (fscanf (procfile, "%d ", &itmp) > 0)
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printf_filtered ("Session id: %d\n", itmp);
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if (fscanf (procfile, "%d ", &itmp) > 0)
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printf_filtered ("TTY: %d\n", itmp);
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if (fscanf (procfile, "%d ", &itmp) > 0)
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printf_filtered ("TTY owner process group: %d\n", itmp);
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if (fscanf (procfile, "%u ", &itmp) > 0)
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printf_filtered ("Flags: 0x%x\n", itmp);
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if (fscanf (procfile, "%u ", &itmp) > 0)
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printf_filtered ("Minor faults (no memory page): %u\n",
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(unsigned int) itmp);
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if (fscanf (procfile, "%u ", &itmp) > 0)
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printf_filtered ("Minor faults, children: %u\n",
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(unsigned int) itmp);
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if (fscanf (procfile, "%u ", &itmp) > 0)
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printf_filtered ("Major faults (memory page faults): %u\n",
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(unsigned int) itmp);
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if (fscanf (procfile, "%u ", &itmp) > 0)
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printf_filtered ("Major faults, children: %u\n",
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(unsigned int) itmp);
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if (fscanf (procfile, "%d ", &itmp) > 0)
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printf_filtered ("utime: %d\n", itmp);
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if (fscanf (procfile, "%d ", &itmp) > 0)
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printf_filtered ("stime: %d\n", itmp);
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if (fscanf (procfile, "%d ", &itmp) > 0)
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printf_filtered ("utime, children: %d\n", itmp);
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if (fscanf (procfile, "%d ", &itmp) > 0)
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printf_filtered ("stime, children: %d\n", itmp);
|
|
if (fscanf (procfile, "%d ", &itmp) > 0)
|
|
printf_filtered ("jiffies remaining in current time slice: %d\n",
|
|
itmp);
|
|
if (fscanf (procfile, "%d ", &itmp) > 0)
|
|
printf_filtered ("'nice' value: %d\n", itmp);
|
|
if (fscanf (procfile, "%u ", &itmp) > 0)
|
|
printf_filtered ("jiffies until next timeout: %u\n",
|
|
(unsigned int) itmp);
|
|
if (fscanf (procfile, "%u ", &itmp) > 0)
|
|
printf_filtered ("jiffies until next SIGALRM: %u\n",
|
|
(unsigned int) itmp);
|
|
if (fscanf (procfile, "%d ", &itmp) > 0)
|
|
printf_filtered ("start time (jiffies since system boot): %d\n",
|
|
itmp);
|
|
if (fscanf (procfile, "%u ", &itmp) > 0)
|
|
printf_filtered ("Virtual memory size: %u\n",
|
|
(unsigned int) itmp);
|
|
if (fscanf (procfile, "%u ", &itmp) > 0)
|
|
printf_filtered ("Resident set size: %u\n", (unsigned int) itmp);
|
|
if (fscanf (procfile, "%u ", &itmp) > 0)
|
|
printf_filtered ("rlim: %u\n", (unsigned int) itmp);
|
|
if (fscanf (procfile, "%u ", &itmp) > 0)
|
|
printf_filtered ("Start of text: 0x%x\n", itmp);
|
|
if (fscanf (procfile, "%u ", &itmp) > 0)
|
|
printf_filtered ("End of text: 0x%x\n", itmp);
|
|
if (fscanf (procfile, "%u ", &itmp) > 0)
|
|
printf_filtered ("Start of stack: 0x%x\n", itmp);
|
|
#if 0 /* Don't know how architecture-dependent the rest is...
|
|
Anyway the signal bitmap info is available from "status". */
|
|
if (fscanf (procfile, "%u ", &itmp) > 0) /* FIXME arch? */
|
|
printf_filtered ("Kernel stack pointer: 0x%x\n", itmp);
|
|
if (fscanf (procfile, "%u ", &itmp) > 0) /* FIXME arch? */
|
|
printf_filtered ("Kernel instr pointer: 0x%x\n", itmp);
|
|
if (fscanf (procfile, "%d ", &itmp) > 0)
|
|
printf_filtered ("Pending signals bitmap: 0x%x\n", itmp);
|
|
if (fscanf (procfile, "%d ", &itmp) > 0)
|
|
printf_filtered ("Blocked signals bitmap: 0x%x\n", itmp);
|
|
if (fscanf (procfile, "%d ", &itmp) > 0)
|
|
printf_filtered ("Ignored signals bitmap: 0x%x\n", itmp);
|
|
if (fscanf (procfile, "%d ", &itmp) > 0)
|
|
printf_filtered ("Catched signals bitmap: 0x%x\n", itmp);
|
|
if (fscanf (procfile, "%u ", &itmp) > 0) /* FIXME arch? */
|
|
printf_filtered ("wchan (system call): 0x%x\n", itmp);
|
|
#endif
|
|
fclose (procfile);
|
|
}
|
|
else
|
|
warning ("unable to open /proc file '%s'", fname1);
|
|
}
|
|
}
|
|
|
|
void
|
|
_initialize_linux_proc (void)
|
|
{
|
|
extern void inftarg_set_find_memory_regions ();
|
|
extern void inftarg_set_make_corefile_notes ();
|
|
|
|
inftarg_set_find_memory_regions (linux_find_memory_regions);
|
|
inftarg_set_make_corefile_notes (linux_make_note_section);
|
|
|
|
add_info ("proc", linux_info_proc_cmd,
|
|
"Show /proc process information about any running process.\n\
|
|
Specify any process id, or use the program being debugged by default.\n\
|
|
Specify any of the following keywords for detailed info:\n\
|
|
mappings -- list of mapped memory regions.\n\
|
|
stat -- list a bunch of random process info.\n\
|
|
status -- list a different bunch of random process info.\n\
|
|
all -- list all available /proc info.");
|
|
}
|
|
|
|
int
|
|
linux_proc_xfer_memory (CORE_ADDR addr, char *myaddr, int len, int write,
|
|
struct mem_attrib *attrib, struct target_ops *target)
|
|
{
|
|
int fd, ret;
|
|
char filename[64];
|
|
|
|
if (write)
|
|
return 0;
|
|
|
|
/* Don't bother for one word. */
|
|
if (len < 3 * sizeof (long))
|
|
return 0;
|
|
|
|
/* We could keep this file open and cache it - possibly one
|
|
per thread. That requires some juggling, but is even faster. */
|
|
sprintf (filename, "/proc/%d/mem", PIDGET (inferior_ptid));
|
|
fd = open (filename, O_RDONLY | O_LARGEFILE);
|
|
if (fd == -1)
|
|
return 0;
|
|
|
|
/* If pread64 is available, use it. It's faster if the kernel
|
|
supports it (only one syscall), and it's 64-bit safe even
|
|
on 32-bit platforms (for instance, SPARC debugging a SPARC64
|
|
application).
|
|
|
|
We play some autoconf and CFLAGS games to get this declaration
|
|
exposed: -D_XOPEN_SOURCE=500 -D_LARGEFILE64_SOURCE. And then
|
|
a -D_BSD_SOURCE to counteract the defaults for _XOPEN_SOURCE. */
|
|
#ifdef HAVE_PREAD64
|
|
if (pread64 (fd, myaddr, len, addr) != len)
|
|
#else
|
|
if (lseek (fd, addr, SEEK_SET) == -1 || read (fd, myaddr, len) != len)
|
|
#endif
|
|
ret = 0;
|
|
else
|
|
ret = len;
|
|
|
|
close (fd);
|
|
return ret;
|
|
}
|