1 /* Linux-specific PROCFS manipulation routines.
2 Copyright (C) 2009-2015 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program 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
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
19 #include "common-defs.h"
20 #include "linux-procfs.h"
21 #include "filestuff.h"
25 /* Return the TGID of LWPID from /proc/pid/status. Returns -1 if not
29 linux_proc_get_int (pid_t lwpid
, const char *field
, int warn
)
31 size_t field_len
= strlen (field
);
36 snprintf (buf
, sizeof (buf
), "/proc/%d/status", (int) lwpid
);
37 status_file
= gdb_fopen_cloexec (buf
, "r");
38 if (status_file
== NULL
)
41 warning (_("unable to open /proc file '%s'"), buf
);
45 while (fgets (buf
, sizeof (buf
), status_file
))
46 if (strncmp (buf
, field
, field_len
) == 0 && buf
[field_len
] == ':')
48 retval
= strtol (&buf
[field_len
+ 1], NULL
, 10);
56 /* Return the TGID of LWPID from /proc/pid/status. Returns -1 if not
60 linux_proc_get_tgid (pid_t lwpid
)
62 return linux_proc_get_int (lwpid
, "Tgid", 1);
65 /* See linux-procfs.h. */
68 linux_proc_get_tracerpid_nowarn (pid_t lwpid
)
70 return linux_proc_get_int (lwpid
, "TracerPid", 0);
73 /* Fill in BUFFER, a buffer with BUFFER_SIZE bytes with the 'State'
74 line of /proc/PID/status. Returns -1 on failure to open the /proc
75 file, 1 if the line is found, and 0 if not found. If WARN, warn on
76 failure to open the /proc file. */
79 linux_proc_pid_get_state (pid_t pid
, char *buffer
, size_t buffer_size
,
85 xsnprintf (buffer
, buffer_size
, "/proc/%d/status", (int) pid
);
86 procfile
= gdb_fopen_cloexec (buffer
, "r");
90 warning (_("unable to open /proc file '%s'"), buffer
);
95 while (fgets (buffer
, buffer_size
, procfile
) != NULL
)
96 if (startswith (buffer
, "State:"))
105 /* See linux-procfs.h declaration. */
108 linux_proc_pid_is_gone (pid_t pid
)
113 have_state
= linux_proc_pid_get_state (pid
, buffer
, sizeof buffer
, 0);
116 /* If we can't open the status file, assume the thread has
120 else if (have_state
== 0)
122 /* No "State:" line, assume thread is alive. */
127 return (strstr (buffer
, "Z (") != NULL
128 || strstr (buffer
, "X (") != NULL
);
132 /* Return non-zero if 'State' of /proc/PID/status contains STATE. If
133 WARN, warn on failure to open the /proc file. */
136 linux_proc_pid_has_state (pid_t pid
, const char *state
, int warn
)
141 have_state
= linux_proc_pid_get_state (pid
, buffer
, sizeof buffer
, warn
);
142 return (have_state
> 0 && strstr (buffer
, state
) != NULL
);
145 /* Detect `T (stopped)' in `/proc/PID/status'.
146 Other states including `T (tracing stop)' are reported as false. */
149 linux_proc_pid_is_stopped (pid_t pid
)
151 return linux_proc_pid_has_state (pid
, "T (stopped)", 1);
154 /* Return non-zero if PID is a zombie. If WARN, warn on failure to
155 open the /proc file. */
158 linux_proc_pid_is_zombie_maybe_warn (pid_t pid
, int warn
)
160 return linux_proc_pid_has_state (pid
, "Z (zombie)", warn
);
163 /* See linux-procfs.h declaration. */
166 linux_proc_pid_is_zombie_nowarn (pid_t pid
)
168 return linux_proc_pid_is_zombie_maybe_warn (pid
, 0);
171 /* See linux-procfs.h declaration. */
174 linux_proc_pid_is_zombie (pid_t pid
)
176 return linux_proc_pid_is_zombie_maybe_warn (pid
, 1);
179 /* See linux-procfs.h declaration. */
182 linux_proc_pid_get_ns (pid_t pid
, const char *ns
)
187 xsnprintf (buf
, sizeof (buf
), "/proc/%d/ns/%s", (int) pid
, ns
);
188 ret
= readlink (buf
, nsval
, sizeof (nsval
));
189 if (0 < ret
&& ret
< sizeof (nsval
))
192 return xstrdup (nsval
);
198 /* See linux-procfs.h. */
201 linux_proc_attach_tgid_threads (pid_t pid
,
202 linux_proc_attach_lwp_func attach_lwp
)
206 int new_threads_found
;
209 if (linux_proc_get_tgid (pid
) != pid
)
212 xsnprintf (pathname
, sizeof (pathname
), "/proc/%ld/task", (long) pid
);
213 dir
= opendir (pathname
);
216 warning (_("Could not open /proc/%ld/task."), (long) pid
);
220 /* Scan the task list for existing threads. While we go through the
221 threads, new threads may be spawned. Cycle through the list of
222 threads until we have done two iterations without finding new
224 for (iterations
= 0; iterations
< 2; iterations
++)
228 new_threads_found
= 0;
229 while ((dp
= readdir (dir
)) != NULL
)
234 lwp
= strtoul (dp
->d_name
, NULL
, 10);
237 ptid_t ptid
= ptid_build (pid
, lwp
, 0);
239 if (attach_lwp (ptid
))
240 new_threads_found
= 1;
244 if (new_threads_found
)
256 /* See linux-procfs.h. */
259 linux_proc_task_list_dir_exists (pid_t pid
)
264 xsnprintf (pathname
, sizeof (pathname
), "/proc/%ld/task", (long) pid
);
265 return (stat (pathname
, &buf
) == 0);