diff options
Diffstat (limited to 'REORG.TODO/elf/pldd.c')
-rw-r--r-- | REORG.TODO/elf/pldd.c | 344 |
1 files changed, 344 insertions, 0 deletions
diff --git a/REORG.TODO/elf/pldd.c b/REORG.TODO/elf/pldd.c new file mode 100644 index 0000000000..ddfa88d63b --- /dev/null +++ b/REORG.TODO/elf/pldd.c @@ -0,0 +1,344 @@ +/* List dynamic shared objects linked into given process. + Copyright (C) 2011-2017 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, see + <http://www.gnu.org/licenses/>. */ + +#include <alloca.h> +#include <argp.h> +#include <assert.h> +#include <dirent.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 <sys/wait.h> +#include <scratch_buffer.h> + +#include <ldsodefs.h> +#include <version.h> + +/* Global variables. */ +extern char *program_invocation_short_name; +#define PACKAGE _libc_intl_domainname + +/* External functions. */ +#include <programs/xmalloc.h> + +/* 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; + +/* Function to print some extra text in the help message. */ +static char *more_help (int key, const char *text, void *input); + +/* 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, more_help, NULL +}; + +// File descriptor of /proc/*/mem file. +static int memfd; + +/* Name of the executable */ +static char *exe; + +/* Local functions. */ +static int get_process_info (int dfd, long int pid); +static void wait_for_ptrace_stop (long int 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; + } + + assert (sizeof (pid_t) == sizeof (int) + || sizeof (pid_t) == sizeof (long int)); + char *endp; + errno = 0; + long int pid = strtol (argv[remaining], &endp, 10); + if (pid < 0 || (pid == ULONG_MAX && errno == ERANGE) || *endp != '\0' + || (sizeof (pid_t) < sizeof (pid) && pid > INT_MAX)) + error (EXIT_FAILURE, 0, gettext ("invalid process ID '%s'"), + argv[remaining]); + + /* Determine the program name. */ + char buf[7 + 3 * sizeof (pid)]; + snprintf (buf, sizeof (buf), "/proc/%lu", pid); + int dfd = open (buf, O_RDONLY | O_DIRECTORY); + if (dfd == -1) + error (EXIT_FAILURE, errno, gettext ("cannot open %s"), buf); + + struct scratch_buffer exebuf; + scratch_buffer_init (&exebuf); + ssize_t nexe; + while ((nexe = readlinkat (dfd, "exe", + exebuf.data, exebuf.length)) == exebuf.length) + { + if (!scratch_buffer_grow (&exebuf)) + { + nexe = -1; + break; + } + } + if (nexe == -1) + exe = (char *) "<program name undetermined>"; + else + { + exe = exebuf.data; + exe[nexe] = '\0'; + } + + /* Stop all threads since otherwise the list of loaded modules might + change while we are reading it. */ + struct thread_list + { + pid_t tid; + struct thread_list *next; + } *thread_list = NULL; + + int taskfd = openat (dfd, "task", O_RDONLY | O_DIRECTORY | O_CLOEXEC); + if (taskfd == 1) + error (EXIT_FAILURE, errno, gettext ("cannot open %s/task"), buf); + DIR *dir = fdopendir (taskfd); + if (dir == NULL) + error (EXIT_FAILURE, errno, gettext ("cannot prepare reading %s/task"), + buf); + + struct dirent64 *d; + while ((d = readdir64 (dir)) != NULL) + { + if (! isdigit (d->d_name[0])) + continue; + + errno = 0; + long int tid = strtol (d->d_name, &endp, 10); + if (tid < 0 || (tid == ULONG_MAX && errno == ERANGE) || *endp != '\0' + || (sizeof (pid_t) < sizeof (pid) && tid > INT_MAX)) + error (EXIT_FAILURE, 0, gettext ("invalid thread ID '%s'"), + d->d_name); + + if (ptrace (PTRACE_ATTACH, tid, NULL, NULL) != 0) + { + /* There might be a race between reading the directory and + threads terminating. Ignore errors attaching to unknown + threads unless this is the main thread. */ + if (errno == ESRCH && tid != pid) + continue; + + error (EXIT_FAILURE, errno, gettext ("cannot attach to process %lu"), + tid); + } + + wait_for_ptrace_stop (tid); + + struct thread_list *newp = alloca (sizeof (*newp)); + newp->tid = tid; + newp->next = thread_list; + thread_list = newp; + } + + closedir (dir); + + int status = get_process_info (dfd, pid); + + assert (thread_list != NULL); + do + { + ptrace (PTRACE_DETACH, thread_list->tid, NULL, NULL); + thread_list = thread_list->next; + } + while (thread_list != NULL); + + close (dfd); + + return status; +} + + +/* Wait for PID to enter ptrace-stop state after being attached. */ +static void +wait_for_ptrace_stop (long int pid) +{ + int status; + + /* While waiting for SIGSTOP being delivered to the tracee we have to + reinject any other pending signal. Ignore all other errors. */ + while (waitpid (pid, &status, __WALL) == pid && WIFSTOPPED (status)) + { + /* The STOP signal should not be delivered to the tracee. */ + if (WSTOPSIG (status) == SIGSTOP) + return; + if (ptrace (PTRACE_CONT, pid, NULL, + (void *) (uintptr_t) WSTOPSIG (status))) + /* The only possible error is that the process died. */ + return; + } +} + + +/* 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 bug-reporting information in the help message. */ +static char * +more_help (int key, const char *text, void *input) +{ + char *tp = NULL; + switch (key) + { + case ARGP_KEY_HELP_EXTRA: + /* We print some extra information. */ + if (asprintf (&tp, gettext ("\ +For bug reporting instructions, please see:\n\ +%s.\n"), REPORT_BUGS_TO) < 0) + return NULL; + return tp; + default: + break; + } + return (char *) text; +} + +/* Print the version information. */ +static void +print_version (FILE *stream, struct argp_state *state) +{ + fprintf (stream, "pldd %s%s\n", PKGVERSION, 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\ +"), "2017"); + 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 (int dfd, long int pid) +{ + memfd = openat (dfd, "mem", O_RDONLY); + if (memfd == -1) + goto no_info; + + int fd = openat (dfd, "exe", O_RDONLY); + if (fd == -1) + { + no_info: + error (0, errno, gettext ("cannot get information about process %lu"), + pid); + return EXIT_FAILURE; + } + + char e_ident[EI_NIDENT]; + if (read (fd, e_ident, EI_NIDENT) != EI_NIDENT) + goto no_info; + + close (fd); + + if (memcmp (e_ident, ELFMAG, SELFMAG) != 0) + { + error (0, 0, gettext ("process %lu is no ELF program"), pid); + return EXIT_FAILURE; + } + + fd = openat (dfd, "auxv", 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 = pread (fd, auxv, auxv_size, 0); + if (n < 0) + goto no_info; + if (n < auxv_size) + { + auxv_size = n; + break; + } + } + + close (fd); + + int retval; + if (e_ident[EI_CLASS] == ELFCLASS32) + retval = find_maps32 (pid, auxv, auxv_size); + else + retval = find_maps64 (pid, auxv, auxv_size); + + free (auxv); + close (memfd); + + return retval; +} |