Add pldd program

1 files changed, 234 insertions, 0 deletions

diff --git a/elf/pldd.c b/elf/pldd.c
new file mode 100644
index 0000000..9fac19e
--- /dev/null
+++ b/elf/pldd.c
@@ -0,0 +1,234 @@
+/* List dynamic shared objects linked into given process.
+   Copyright (C) 2011 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@gmail.com>, 2011.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <alloca.h>
+#include <argp.h>
+#include <elf.h>
+#include <errno.h>
+#include <error.h>
+#include <fcntl.h>
+#include <libintl.h>
+#include <link.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/ptrace.h>
+#include <sys/stat.h>
+
+#include <ldsodefs.h>
+#include <version.h>
+
+/* Global variables.  */
+extern char *program_invocation_short_name;
+#define PACKAGE _libc_intl_domainname
+
+/* External functions.  */
+extern void *xmalloc (size_t n);
+extern void *xrealloc (void *p, size_t n);
+
+/* Name and version of program.  */
+static void print_version (FILE *stream, struct argp_state *state);
+void (*argp_program_version_hook) (FILE *, struct argp_state *) = print_version;
+
+/* Bug report address.  */
+const char *argp_program_bug_address = N_("\
+For bug reporting instructions, please see:\n\
+<http://www.gnu.org/software/libc/bugs.html>.\n");
+
+/* Definitions of arguments for argp functions.  */
+static const struct argp_option options[] =
+{
+  { NULL, 0, NULL, 0, NULL }
+};
+
+/* Short description of program.  */
+static const char doc[] = N_("\
+List dynamic shared objects loaded into process.");
+
+/* Strings for arguments in help texts.  */
+static const char args_doc[] = N_("PID");
+
+/* Prototype for option handler.  */
+static error_t parse_opt (int key, char *arg, struct argp_state *state);
+
+/* Data structure to communicate with argp functions.  */
+static struct argp argp =
+{
+  options, parse_opt, args_doc, doc, NULL, NULL, NULL
+};
+
+// File descriptor of /proc/*/mem file.
+static int memfd;
+
+/* Name of the executable  */
+static char *exe;
+
+/* Local functions.  */
+static int get_process_info (pid_t pid);
+
+
+int
+main (int argc, char *argv[])
+{
+  /* Parse and process arguments.  */
+  int remaining;
+  argp_parse (&argp, argc, argv, 0, &remaining, NULL);
+
+  if (remaining != argc - 1)
+    {
+      fprintf (stderr,
+	       gettext ("Exactly one parameter with process ID required.\n"));
+      argp_help (&argp, stderr, ARGP_HELP_SEE, program_invocation_short_name);
+      return 1;
+    }
+
+  char *endp;
+  errno = 0;
+  pid_t pid = strtoul (argv[remaining], &endp, 10);
+  if ((pid == ULONG_MAX && errno == ERANGE) || *endp != '\0')
+    error (EXIT_FAILURE, 0, gettext ("invalid process ID '%s'"),
+	   argv[remaining]);
+
+  /* Determine the program name.  */
+  char buf[11 + 3 * sizeof (pid)];
+  snprintf (buf, sizeof (buf), "/proc/%lu/exe", (unsigned long int) pid);
+  size_t exesize = 1024;
+  exe = alloca (exesize);
+  ssize_t nexe;
+  while ((nexe = readlink (buf, exe, exesize)) == exesize)
+    extend_alloca (exe, exesize, 2 * exesize);
+  if (nexe == -1)
+    exe = (char *) "<program name undetermined>";
+  else
+    exe[nexe] = '\0';
+
+  if (ptrace (PTRACE_ATTACH, pid, NULL, NULL) != 0)
+    error (EXIT_FAILURE, errno, gettext ("cannot attach to process %lu"),
+	   (unsigned long int) pid);
+
+  int status = get_process_info (pid);
+
+  ptrace (PTRACE_DETACH, pid, NULL, NULL);
+
+  return status;
+}
+
+
+/* Handle program arguments.  */
+static error_t
+parse_opt (int key, char *arg, struct argp_state *state)
+{
+  switch (key)
+    {
+    default:
+      return ARGP_ERR_UNKNOWN;
+    }
+  return 0;
+}
+
+
+/* Print the version information.  */
+static void
+print_version (FILE *stream, struct argp_state *state)
+{
+  fprintf (stream, "pldd (GNU %s) %s\n", PACKAGE, VERSION);
+  fprintf (stream, gettext ("\
+Copyright (C) %s Free Software Foundation, Inc.\n\
+This is free software; see the source for copying conditions.  There is NO\n\
+warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n\
+"), "2011");
+  fprintf (stream, gettext ("Written by %s.\n"), "Ulrich Drepper");
+}
+
+
+#define CLASS 32
+#include "pldd-xx.c"
+#define CLASS 64
+#include "pldd-xx.c"
+
+
+static int
+get_process_info (pid_t pid)
+{
+  char buf[12 + 3 * sizeof (pid)];
+
+  snprintf (buf, sizeof (buf), "/proc/%lu/mem", (unsigned long int) pid);
+  memfd = open (buf, O_RDONLY);
+  if (memfd == -1)
+    goto no_info;
+
+  snprintf (buf, sizeof (buf), "/proc/%lu/exe", (unsigned long int) pid);
+  int fd = open (buf, O_RDONLY);
+  if (fd == -1)
+    {
+    no_info:
+      error (0, errno, gettext ("cannot get information about process %lu"),
+	     (unsigned long int) pid);
+      return EXIT_FAILURE;
+    }
+
+  union
+  {
+    Elf32_Ehdr ehdr32;
+    Elf64_Ehdr ehdr64;
+  } uehdr;
+  if (read (fd, &uehdr, sizeof (uehdr)) != sizeof (uehdr))
+    goto no_info;
+
+  close (fd);
+
+  if (memcmp (uehdr.ehdr32.e_ident, ELFMAG, SELFMAG) != 0)
+    {
+      error (0, 0, gettext ("process %lu is no ELF program"),
+	     (unsigned long int) pid);
+      return EXIT_FAILURE;
+    }
+
+  snprintf (buf, sizeof (buf), "/proc/%lu/auxv", (unsigned long int) pid);
+  fd = open (buf, O_RDONLY);
+  if (fd == -1)
+    goto no_info;
+
+  size_t auxv_size = 0;
+  void *auxv = NULL;
+  while (1)
+    {
+      auxv_size += 512;
+      auxv = xrealloc (auxv, auxv_size);
+
+      ssize_t n = read (fd, auxv, auxv_size);
+      if (n < 0)
+	goto no_info;
+      if (n < auxv_size)
+	{
+	  auxv_size = n;
+	  break;
+	}
+    }
+
+  close (fd);
+
+  if (uehdr.ehdr32.e_ident[EI_CLASS] == ELFCLASS32)
+    return find_maps32 (pid, &uehdr.ehdr32, auxv, auxv_size);
+  else
+    return find_maps64 (pid, &uehdr.ehdr64, auxv, auxv_size);
+}