1 /* List dynamic shared objects linked into given process.
2 Copyright (C) 2011-2015 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Ulrich Drepper <drepper@gmail.com>, 2011.
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
11 The GNU C Library 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 GNU
14 Lesser General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, see
18 <http://www.gnu.org/licenses/>. */
35 #include <sys/ptrace.h>
42 /* Global variables. */
43 extern char *program_invocation_short_name;
44 #define PACKAGE _libc_intl_domainname
46 /* External functions. */
47 #include <programs/xmalloc.h>
49 /* Name and version of program. */
50 static void print_version (FILE *stream, struct argp_state *state);
51 void (*argp_program_version_hook) (FILE *, struct argp_state *) = print_version;
53 /* Function to print some extra text in the help message. */
54 static char *more_help (int key, const char *text, void *input);
56 /* Definitions of arguments for argp functions. */
57 static const struct argp_option options[] =
59 { NULL, 0, NULL, 0, NULL }
62 /* Short description of program. */
63 static const char doc[] = N_("\
64 List dynamic shared objects loaded into process.");
66 /* Strings for arguments in help texts. */
67 static const char args_doc[] = N_("PID");
69 /* Prototype for option handler. */
70 static error_t parse_opt (int key, char *arg, struct argp_state *state);
72 /* Data structure to communicate with argp functions. */
73 static struct argp argp =
75 options, parse_opt, args_doc, doc, NULL, more_help, NULL
78 // File descriptor of /proc/*/mem file.
81 /* Name of the executable */
84 /* Local functions. */
85 static int get_process_info (int dfd, long int pid);
86 static void wait_for_ptrace_stop (long int pid);
90 main (int argc, char *argv[])
92 /* Parse and process arguments. */
94 argp_parse (&argp, argc, argv, 0, &remaining, NULL);
96 if (remaining != argc - 1)
99 gettext ("Exactly one parameter with process ID required.\n"));
100 argp_help (&argp, stderr, ARGP_HELP_SEE, program_invocation_short_name);
104 assert (sizeof (pid_t) == sizeof (int)
105 || sizeof (pid_t) == sizeof (long int));
108 long int pid = strtol (argv[remaining], &endp, 10);
109 if (pid < 0 || (pid == ULONG_MAX && errno == ERANGE) || *endp != '\0'
110 || (sizeof (pid_t) < sizeof (pid) && pid > INT_MAX))
111 error (EXIT_FAILURE, 0, gettext ("invalid process ID '%s'"),
114 /* Determine the program name. */
115 char buf[7 + 3 * sizeof (pid)];
116 snprintf (buf, sizeof (buf), "/proc/%lu", pid);
117 int dfd = open (buf, O_RDONLY | O_DIRECTORY);
119 error (EXIT_FAILURE, errno, gettext ("cannot open %s"), buf);
121 size_t exesize = 1024;
125 exe = alloca (exesize);
127 while ((nexe = readlinkat (dfd, "exe", exe, exesize)) == exesize)
128 extend_alloca (exe, exesize, 2 * exesize);
130 exe = (char *) "<program name undetermined>";
134 /* Stop all threads since otherwise the list of loaded modules might
135 change while we are reading it. */
139 struct thread_list *next;
140 } *thread_list = NULL;
142 int taskfd = openat (dfd, "task", O_RDONLY | O_DIRECTORY | O_CLOEXEC);
144 error (EXIT_FAILURE, errno, gettext ("cannot open %s/task"), buf);
145 DIR *dir = fdopendir (taskfd);
147 error (EXIT_FAILURE, errno, gettext ("cannot prepare reading %s/task"),
151 while ((d = readdir64 (dir)) != NULL)
153 if (! isdigit (d->d_name[0]))
157 long int tid = strtol (d->d_name, &endp, 10);
158 if (tid < 0 || (tid == ULONG_MAX && errno == ERANGE) || *endp != '\0'
159 || (sizeof (pid_t) < sizeof (pid) && tid > INT_MAX))
160 error (EXIT_FAILURE, 0, gettext ("invalid thread ID '%s'"),
163 if (ptrace (PTRACE_ATTACH, tid, NULL, NULL) != 0)
165 /* There might be a race between reading the directory and
166 threads terminating. Ignore errors attaching to unknown
167 threads unless this is the main thread. */
168 if (errno == ESRCH && tid != pid)
171 error (EXIT_FAILURE, errno, gettext ("cannot attach to process %lu"),
175 wait_for_ptrace_stop (tid);
177 struct thread_list *newp = alloca (sizeof (*newp));
179 newp->next = thread_list;
185 int status = get_process_info (dfd, pid);
187 assert (thread_list != NULL);
190 ptrace (PTRACE_DETACH, thread_list->tid, NULL, NULL);
191 thread_list = thread_list->next;
193 while (thread_list != NULL);
201 /* Wait for PID to enter ptrace-stop state after being attached. */
203 wait_for_ptrace_stop (long int pid)
207 /* While waiting for SIGSTOP being delivered to the tracee we have to
208 reinject any other pending signal. Ignore all other errors. */
209 while (waitpid (pid, &status, __WALL) == pid && WIFSTOPPED (status))
211 /* The STOP signal should not be delivered to the tracee. */
212 if (WSTOPSIG (status) == SIGSTOP)
214 if (ptrace (PTRACE_CONT, pid, NULL,
215 (void *) (uintptr_t) WSTOPSIG (status)))
216 /* The only possible error is that the process died. */
222 /* Handle program arguments. */
224 parse_opt (int key, char *arg, struct argp_state *state)
229 return ARGP_ERR_UNKNOWN;
235 /* Print bug-reporting information in the help message. */
237 more_help (int key, const char *text, void *input)
242 case ARGP_KEY_HELP_EXTRA:
243 /* We print some extra information. */
244 if (asprintf (&tp, gettext ("\
245 For bug reporting instructions, please see:\n\
246 %s.\n"), REPORT_BUGS_TO) < 0)
252 return (char *) text;
255 /* Print the version information. */
257 print_version (FILE *stream, struct argp_state *state)
259 fprintf (stream, "pldd %s%s\n", PKGVERSION, VERSION);
260 fprintf (stream, gettext ("\
261 Copyright (C) %s Free Software Foundation, Inc.\n\
262 This is free software; see the source for copying conditions. There is NO\n\
263 warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n\
265 fprintf (stream, gettext ("Written by %s.\n"), "Ulrich Drepper");
276 get_process_info (int dfd, long int pid)
278 memfd = openat (dfd, "mem", O_RDONLY);
282 int fd = openat (dfd, "exe", O_RDONLY);
286 error (0, errno, gettext ("cannot get information about process %lu"),
291 char e_ident[EI_NIDENT];
292 if (read (fd, e_ident, EI_NIDENT) != EI_NIDENT)
297 if (memcmp (e_ident, ELFMAG, SELFMAG) != 0)
299 error (0, 0, gettext ("process %lu is no ELF program"), pid);
303 fd = openat (dfd, "auxv", O_RDONLY);
307 size_t auxv_size = 0;
312 auxv = xrealloc (auxv, auxv_size);
314 ssize_t n = pread (fd, auxv, auxv_size, 0);
327 if (e_ident[EI_CLASS] == ELFCLASS32)
328 retval = find_maps32 (pid, auxv, auxv_size);
330 retval = find_maps64 (pid, auxv, auxv_size);