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psmisc/psmisc-22.21-upstream.patch

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. OBS-URL: https://build.opensuse.org/package/show/Base:System/psmisc?expand=0&rev=70
2014-03-24 17:13:40 +01:00
--- ChangeLog
+++ ChangeLog 2014-03-24 00:00:00.000000000 +0000
@@ -1,3 +1,9 @@
+ * Make usage of linked lists of devices found in
+ /proc/self/mountinfo optional
+ * Make timeout() in timeout.c work with shared mmap to
+ reduce the load due write/read the stat buffers
+ * Add list_sort() to lists.h to be able to sort lists
+
Changes in 22.21
================
* Missing comma in fuser(1) added Debian #702391
--- configure.ac
+++ configure.ac 2014-03-24 00:00:00.000000000 +0000
@@ -42,6 +42,17 @@ if test "$enable_timeout_stat" = "static
fi
AM_CONDITIONAL([WANT_TIMEOUT_STAT], [test "$enable_timeout_stat" = "static"])
+# Use string search for network based file systems but only if the system
+# has /proc/self/mountinfo
+AC_SUBST([WITH_MOUNTINFO_LIST])
+AC_ARG_ENABLE([mountinfo_list],
+ [AS_HELP_STRING([--enable-mountinfo-list], [Use the list in /proc/self/mountinfo to replace stat(2) syscall on network file systems shares])],
+ [enable_mountinfo_list="yes"],
+ [enable_mountinfo_list="no"])
+if test "$enable_mountinfo_list" = "yes" -a -e /proc/self/mountinfo ; then
+ AC_DEFINE([WITH_MOUNTINFO_LIST], [1], [Use list in /proc/self/mountinfo to replace stat calls])
+fi
+
# Enable hardened compile and link flags
AC_ARG_ENABLE([harden_flags],
[AS_HELP_STRING([--disable-harden-flags], [disable hardened compilier and linker flags])],
--- src/fuser.c
+++ src/fuser.c 2014-03-24 15:50:46.202235621 +0000
@@ -58,6 +58,7 @@
#include "fuser.h"
#include "signals.h"
#include "i18n.h"
+#include "timeout.h"
//#define DEBUG 1
@@ -104,25 +105,14 @@ static void debug_match_lists(struct nam
struct device_list *dev_head);
#endif
-#ifdef _LISTS_H
+#if defined(WITH_MOUNTINFO_LIST)
static void clear_mntinfo(void) __attribute__ ((__destructor__));
static void init_mntinfo(void) __attribute__ ((__constructor__));
-static dev_t device(const char *path);
+static int mntstat(const char *path, struct stat *buf);
#endif
+static stat_t thestat = stat;
static char *expandpath(const char *path);
-#ifdef WITH_TIMEOUT_STAT
-#if (WITH_TIMEOUT_STAT == 2)
-#include "timeout.h"
-#else
-typedef int (*stat_t) (const char *, struct stat *);
-static int timeout(stat_t func, const char *path, struct stat *buf,
- unsigned int seconds);
-#endif
-#else
-#define timeout(func,path,buf,dummy) (func)((path),(buf))
-#endif /* WITH_TIMEOUT_STAT */
-
static void usage(const char *errormsg)
{
if (errormsg != NULL)
@@ -191,10 +181,6 @@ scan_procs(struct names *names_head, str
struct stat *cwd_stat = NULL;
struct stat *exe_stat = NULL;
struct stat *root_stat = NULL;
-#ifdef _LISTS_H
- char path[256] = "/proc/", *slash;
- ssize_t len;
-#endif
if (topproc_dent->d_name[0] < '0' || topproc_dent->d_name[0] > '9') /* Not a process */
continue;
@@ -204,30 +190,12 @@ scan_procs(struct names *names_head, str
continue;
uid = getpiduid(pid);
-#ifdef _LISTS_H
- strcpy(&path[6], topproc_dent->d_name);
- len = strlen(path);
- slash = &path[len];
-
- *slash = '\0';
- strcat(slash, "/cwd");
- cwd_dev = device(path);
-
- *slash = '\0';
- strcat(slash, "/exe");
- exe_dev = device(path);
-
- *slash = '\0';
- strcat(slash, "/root");
- root_dev = device(path);
-#else
cwd_stat = get_pidstat(pid, "cwd");
exe_stat = get_pidstat(pid, "exe");
root_stat = get_pidstat(pid, "root");
cwd_dev = cwd_stat ? cwd_stat->st_dev : 0;
exe_dev = exe_stat ? exe_stat->st_dev : 0;
root_dev = root_stat ? root_stat->st_dev : 0;
-#endif
/* Scan the devices */
for (dev_tmp = dev_head; dev_tmp != NULL;
@@ -463,7 +431,7 @@ add_special_proc(struct names *name_list
}
int parse_file(struct names *this_name, struct inode_list **ino_list,
- const char opts)
+ const opt_type opts)
{
char *new = expandpath(this_name->filename);
if (new) {
@@ -471,8 +439,7 @@ int parse_file(struct names *this_name,
free(this_name->filename);
this_name->filename = strdup(new);
}
-
- if (timeout(stat, this_name->filename, &(this_name->st), 5) != 0) {
+ if (timeout(thestat, this_name->filename, &(this_name->st), 5) != 0) {
if (errno == ENOENT)
fprintf(stderr,
_("Specified filename %s does not exist.\n"),
@@ -514,7 +481,7 @@ parse_unixsockets(struct names *this_nam
int
parse_mounts(struct names *this_name, struct device_list **dev_list,
- const char opts)
+ const opt_type opts)
{
dev_t match_device;
@@ -1015,6 +982,10 @@ int main(int argc, char *argv[])
break;
case 'c':
opts |= OPT_MOUNTS;
+#if defined(WITH_MOUNTINFO_LIST)
+ thestat = mntstat;
+#endif
+ read_proc_mounts(&mounts);
break;
case 'f':
/* ignored */
@@ -1033,6 +1004,9 @@ int main(int argc, char *argv[])
return 0;
case 'm':
opts |= OPT_MOUNTS;
+#if defined(WITH_MOUNTINFO_LIST)
+ thestat = mntstat;
+#endif
read_proc_mounts(&mounts);
break;
case 'M':
@@ -1401,7 +1375,7 @@ static struct stat *get_pidstat(const pi
if ((st = (struct stat *)malloc(sizeof(struct stat))) == NULL)
return NULL;
snprintf(pathname, 256, "/proc/%d/%s", pid, filename);
- if (timeout(stat, pathname, st, 5) != 0) {
+ if (timeout(thestat, pathname, st, 5) != 0) {
free(st);
return NULL;
}
@@ -1433,7 +1407,7 @@ check_dir(const pid_t pid, const char *d
snprintf(filepath, MAX_PATHNAME, "/proc/%d/%s/%s",
pid, dirname, direntry->d_name);
- if (timeout(stat, filepath, &st, 5) != 0) {
+ if (timeout(thestat, filepath, &st, 5) != 0) {
if (errno != ENOENT && errno != ENOTDIR) {
fprintf(stderr, _("Cannot stat file %s: %s\n"),
filepath, strerror(errno));
@@ -1472,7 +1446,7 @@ check_dir(const pid_t pid, const char *d
if (thedev != ino_tmp->device)
continue;
if (!st.st_ino
- && timeout(stat, filepath, &st, 5) != 0) {
+ && timeout(thestat, filepath, &st, 5) != 0) {
fprintf(stderr,
_("Cannot stat file %s: %s\n"),
filepath, strerror(errno));
@@ -1542,7 +1516,7 @@ static uid_t getpiduid(const pid_t pid)
if (snprintf(pathname, MAX_PATHNAME, "/proc/%d", pid) < 0)
return 0;
- if (timeout(stat, pathname, &st, 5) != 0)
+ if (timeout(thestat, pathname, &st, 5) != 0)
return 0;
return st.st_uid;
}
@@ -1578,7 +1552,7 @@ void fill_unix_cache(struct unixsocket_l
path = scanned_path;
if (*scanned_path == '@')
scanned_path++;
- if (timeout(stat, scanned_path, &st, 5) < 0) {
+ if (timeout(thestat, scanned_path, &st, 5) < 0) {
free(path);
continue;
}
@@ -1723,7 +1697,7 @@ scan_knfsd(struct names *names_head, str
if ((find_space = strpbrk(line, " \t")) == NULL)
continue;
*find_space = '\0';
- if (timeout(stat, line, &st, 5) != 0) {
+ if (timeout(thestat, line, &st, 5) != 0) {
continue;
}
/* Scan the devices */
@@ -1767,7 +1741,7 @@ scan_mounts(struct names *names_head, st
if ((find_space = strchr(find_mountp, ' ')) == NULL)
continue;
*find_space = '\0';
- if (timeout(stat, find_mountp, &st, 5) != 0) {
+ if (timeout(thestat, find_mountp, &st, 5) != 0) {
continue;
}
/* Scan the devices */
@@ -1814,7 +1788,7 @@ scan_swaps(struct names *names_head, str
if (*find_space == '\0')
continue;
}
- if (timeout(stat, line, &st, 5) != 0) {
+ if (timeout(thestat, line, &st, 5) != 0) {
continue;
}
/* Scan the devices */
@@ -1835,73 +1809,7 @@ scan_swaps(struct names *names_head, str
fclose(fp);
}
-/*
- * Execute stat(2) system call with timeout to avoid deadlock
- * on network based file systems.
- */
-#if defined(WITH_TIMEOUT_STAT) && (WITH_TIMEOUT_STAT == 1)
-
-static sigjmp_buf jenv;
-
-static void sigalarm(int sig)
-{
- if (sig == SIGALRM)
- siglongjmp(jenv, 1);
-}
-
-static int
-timeout(stat_t func, const char *path, struct stat *buf, unsigned int seconds)
-{
- pid_t pid = 0;
- int ret = 0, pipes[4];
- ssize_t len;
-
- if (pipe(&pipes[0]) < 0)
- goto err;
- switch ((pid = fork())) {
- case -1:
- close(pipes[0]);
- close(pipes[1]);
- goto err;
- case 0:
- (void)signal(SIGALRM, SIG_DFL);
- close(pipes[0]);
- if ((ret = func(path, buf)) == 0)
- do
- len = write(pipes[1], buf, sizeof(struct stat));
- while (len < 0 && errno == EINTR);
- close(pipes[1]);
- exit(ret);
- default:
- close(pipes[1]);
- if (sigsetjmp(jenv, 1)) {
- (void)alarm(0);
- (void)signal(SIGALRM, SIG_DFL);
- if (waitpid(0, (int *)0, WNOHANG) == 0)
- kill(pid, SIGKILL);
- errno = ETIMEDOUT;
- seconds = 1;
- goto err;
- }
- (void)signal(SIGALRM, sigalarm);
- (void)alarm(seconds);
- if (read(pipes[0], buf, sizeof(struct stat)) == 0) {
- errno = EFAULT;
- ret = -1;
- }
- (void)alarm(0);
- (void)signal(SIGALRM, SIG_DFL);
- close(pipes[0]);
- waitpid(pid, NULL, 0);
- break;
- }
- return ret;
- err:
- return -1;
-}
-#endif /* WITH_TIMEOUT_STAT */
-
-#ifdef _LISTS_H
+#if defined(WITH_MOUNTINFO_LIST)
/*
* Use /proc/self/mountinfo of modern linux system to determine
* the device numbers of the mount points. Use this to avoid the
@@ -1990,42 +1898,46 @@ static void init_mntinfo(void)
/*
* Determine device of links below /proc/
*/
-static dev_t device(const char *path)
+static int mntstat(const char *path, struct stat *buf)
{
char name[PATH_MAX + 1];
const char *use;
ssize_t nlen;
list_t *ptr;
- if ((nlen = readlink(path, name, PATH_MAX)) < 0) {
- nlen = strlen(path);
- use = &path[0];
- } else {
- name[nlen] = '\0';
- use = &name[0];
- }
-
- if (*use != '/') { /* special file (socket, pipe, inotify) */
- struct stat st;
- if (timeout(stat, path, &st, 5) != 0)
- return (dev_t) - 1;
- return st.st_dev;
+ if ((use = realpath(path, name)) == NULL || *use != '/')
+ {
+ if (errno == ENOENT)
+ return -1;
+ /*
+ * Could be a special file (socket, pipe, inotify)
+ */
+ errno = 0;
+ return stat(path, buf);
}
+ nlen = strlen(use);
list_for_each(ptr, &mntinfo) {
mntinfo_t *mnt = list_entry(ptr, mntinfo_t);
if (nlen < mnt->nlen)
continue;
- if (mnt->nlen == 1) /* root fs is the last entry */
- return mnt->dev;
+ if (mnt->nlen == 1) { /* root fs is the last entry */
+ buf->st_dev = mnt->dev;
+ buf->st_ino = 0;
+ return 0;
+ }
if (use[mnt->nlen] != '\0' && use[mnt->nlen] != '/')
continue;
- if (strncmp(use, mnt->mpoint, mnt->nlen) == 0)
- return mnt->dev;
+ if (strncmp(use, mnt->mpoint, mnt->nlen) == 0) {
+ buf->st_dev = mnt->dev;
+ buf->st_ino = 0;
+ return 0;
+ }
}
- return (dev_t) - 1;
+ errno = ENOENT;
+ return -1;
}
-#endif /* _LISTS_H */
+#endif /* WITH_MOUNTINFO_LIST */
/*
* Somehow the realpath(3) glibc function call, nevertheless
--- src/fuser.h
+++ src/fuser.h 2014-03-24 00:00:00.000000000 +0000
@@ -86,7 +86,7 @@ struct mount_list {
struct mount_list *next;
};
-#if defined (__GNUC__) && defined(__OPTIMIZE__) && !defined (__CYGWIN__)
+#if defined (__GNUC__) && defined(WITH_MOUNTINFO_LIST)
# include "lists.h"
typedef struct mntinfo_s {
list_t this;
@@ -95,6 +95,8 @@ typedef struct mntinfo_s {
size_t nlen;
char *mpoint;
} mntinfo_t;
+#else
+# undef WITH_MOUNTINFO_LIST
#endif
#define NAMESPACE_FILE 0
--- src/lists.h
+++ src/lists.h 2014-03-24 00:00:00.000000000 +0000
@@ -1,10 +1,10 @@
/*
- * lists.h Simple doubly linked list implementation,
- * based on <linux/list.h> and <linux/prefetch.h>.
+ * lists.h Simple doubly linked list implementation, based on
+ * <linux/list.h>, <linux/prefetch.h>, and lib/list_sort.c
*
- * Version: 0.1 01-Feb-2011 Fink
+ * Version: 0.2 11-Dec-2012 Fink
*
- * Copyright 2011 Werner Fink, 2005 SUSE LINUX Products GmbH, Germany.
+ * Copyright 2011,2012 Werner Fink, 2005,2012 SUSE LINUX Products GmbH, Germany.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -246,4 +246,128 @@ static inline void move_tail(list_t *res
#define np_list_for_each_prev(pos, head) \
for (pos = (head)->prev; pos != (head); pos = pos->prev)
+#define MAX_LIST_LENGTH_BITS 20
+
+/*
+ * Returns a list organized in an intermediate format suited
+ * to chaining of merge() calls: null-terminated, no reserved or
+ * sentinel head node, "prev" links not maintained.
+ */
+static inline list_t *merge(int (*cmp)(list_t *a, list_t *b), list_t *a, list_t *b)
+{
+ list_t head, *tail = &head;
+ while (a && b) {
+ /* if equal, take 'a' -- important for sort stability */
+ if ((*cmp)(a, b) <= 0) {
+ tail->next = a;
+ a = a->next;
+ } else {
+ tail->next = b;
+ b = b->next;
+ }
+ tail = tail->next;
+ }
+ tail->next = a ? a : b;
+ return head.next;
+}
+
+/*
+ * Combine final list merge with restoration of standard doubly-linked
+ * list structure. This approach duplicates code from merge(), but
+ * runs faster than the tidier alternatives of either a separate final
+ * prev-link restoration pass, or maintaining the prev links
+ * throughout.
+ */
+static inline void merge_and_restore_back_links(int (*cmp)(list_t *a, list_t *b), list_t *head, list_t *a, list_t *b)
+{
+ list_t *tail = head;
+
+ while (a && b) {
+ /* if equal, take 'a' -- important for sort stability */
+ if ((*cmp)(a, b) <= 0) {
+ tail->next = a;
+ a->prev = tail;
+ a = a->next;
+ } else {
+ tail->next = b;
+ b->prev = tail;
+ b = b->next;
+ }
+ tail = tail->next;
+ }
+ tail->next = a ? a : b;
+
+ do {
+ /*
+ * In worst cases this loop may run many iterations.
+ * Continue callbacks to the client even though no
+ * element comparison is needed, so the client's cmp()
+ * routine can invoke cond_resched() periodically.
+ */
+ (*cmp)(tail->next, tail->next);
+
+ tail->next->prev = tail;
+ tail = tail->next;
+ } while (tail->next);
+
+ tail->next = head;
+ head->prev = tail;
+}
+
+
+/**
+ * list_sort - sort a list
+ * @head: the list to sort
+ * @cmp: the elements comparison function
+ *
+ * This function implements "merge sort", which has O(nlog(n))
+ * complexity.
+ *
+ * The comparison function @cmp must return a negative value if @a
+ * should sort before @b, and a positive value if @a should sort after
+ * @b. If @a and @b are equivalent, and their original relative
+ * ordering is to be preserved, @cmp must return 0.
+ */
+static inline void list_sort(list_t *head, int (*cmp)(list_t *a, list_t *b))
+{
+ list_t *part[MAX_LIST_LENGTH_BITS+1]; /* sorted partial lists
+ -- last slot is a sentinel */
+ size_t lev; /* index into part[] */
+ size_t max_lev = 0;
+ list_t *list;
+
+ if (list_empty(head))
+ return;
+
+ memset(part, 0, sizeof(part));
+
+ head->prev->next = NULL;
+ list = head->next;
+
+ while (list) {
+ list_t *cur = list;
+ list = list->next;
+ cur->next = NULL;
+
+ for (lev = 0; part[lev]; lev++) {
+ cur = merge(cmp, part[lev], cur);
+ part[lev] = NULL;
+ }
+ if (lev > max_lev) {
+ /* list passed to list_sort() too long for efficiency */
+ if (lev >= MAX_LIST_LENGTH_BITS)
+ lev--;
+ max_lev = lev;
+ }
+ part[lev] = cur;
+ }
+
+ for (lev = 0; lev < max_lev; lev++) {
+ if (part[lev])
+ list = merge(cmp, part[lev], list);
+ }
+
+ merge_and_restore_back_links(cmp, head, part[max_lev], list);
+}
+
#endif /* _LISTS_H */
--- src/timeout.c
+++ src/timeout.c 2014-03-24 00:00:00.000000000 +0000
@@ -2,9 +2,9 @@
* timout.c Advanced timeout handling for file system calls
* to avoid deadlocks on remote file shares.
*
- * Version: 0.1 07-Sep-2011 Fink
+ * Version: 0.2 11-Dec-2012 Fink
*
- * Copyright 2011 Werner Fink, 2011 SUSE LINUX Products GmbH, Germany.
+ * Copyright 2011,2012 Werner Fink, 2011,2012 SUSE LINUX Products GmbH, Germany.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -18,26 +18,29 @@
# define _GNU_SOURCE
#endif
-#ifndef USE_SOCKETPAIR
-# define USE_SOCKETPAIR 1
-#endif
-
#ifdef _FEATURES_H
# error Include local config.h before any system header file
#endif
-#include "config.h" /* For _FILE_OFFSET_BITS */
+#include "config.h"
+
+#ifndef WITH_TIMEOUT_STAT
+# define WITH_TIMEOUT_STAT 0
+#endif
+
+#ifndef USE_SOCKETPAIR
+# define USE_SOCKETPAIR 1
+#endif
#include <errno.h>
-#include <pthread.h>
#include <setjmp.h>
#include <signal.h>
#include <stdlib.h>
#include <string.h>
+#include <sys/mman.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/select.h>
#include <sys/stat.h>
-
#include <unistd.h>
#if USE_SOCKETPAIR
# include <sys/socket.h>
@@ -86,6 +89,15 @@
# define strcpy(d,s) __builtin_strcpy((d),(s)) /* Without boundary check please */
#endif
+#if WITH_TIMEOUT_STAT
+static sigjmp_buf jenv;
+static void sigjump(int sig attribute((unused)))
+{
+ siglongjmp(jenv, 1);
+}
+#endif
+
+#if WITH_TIMEOUT_STAT == 2
/*
* The structure used for communication between the processes
*/
@@ -106,7 +118,8 @@ typedef struct _handle {
static volatile pid_t active;
static int pipes[4] = {-1, -1, -1, -1};
-static char buf[PATH_MAX + sizeof(handle_t) + 1];
+static handle_t *restrict handle;
+static const size_t buflen = PATH_MAX+sizeof(handle_t)+1;
static void sigchild(int sig attribute((unused)))
{
@@ -122,6 +135,7 @@ static void attribute((constructor)) sta
{
sigset_t sigset, oldset;
struct sigaction act;
+ char sync[1];
ssize_t in;
if (pipes[1] >= 0) close(pipes[1]);
@@ -138,6 +152,12 @@ static void attribute((constructor)) sta
act.sa_handler = sigchild;
sigaction(SIGCHLD, &act, 0);
+ if (!handle)
+ handle = mmap(NULL, buflen, PROT_READ|PROT_WRITE,
+ MAP_ANONYMOUS|MAP_SHARED, -1, 0);
+ if (handle == MAP_FAILED)
+ goto error;
+
if ((active = fork()) < 0)
goto error;
@@ -164,16 +184,22 @@ static void attribute((constructor)) sta
pipes[1] = pipes[2] = -1;
pipes[0] = pipes[3] = -1;
- {
- handle_t *restrict handle = (void*)&buf[0];
-
- while ((in = read(STDIN_FILENO, handle, sizeof(buf))) > sizeof(handle_t)) {
- if (handle->function(handle->path, &handle->argument) < 0)
- handle->errcode = errno;
- write(STDOUT_FILENO, &handle->errcode, sizeof(handle->errcode)+sizeof(handle->argument));
- memset(handle, 0, sizeof(handle_t));
+ while ((in = read(STDIN_FILENO, &sync, sizeof(sync))) != 0) {
+ ssize_t out;
+ if (in < 0) {
+ if (errno == EINTR)
+ continue;
+ break;
}
+ if (!handle)
+ break;
+ if (handle->function(handle->path, &handle->argument) < 0)
+ handle->errcode = errno;
+ do
+ out = write(STDOUT_FILENO, &sync, sizeof(sync));
+ while (out < 0 && errno == EINTR);
}
+
sigprocmask(SIG_SETMASK, &oldset, NULL);
exit(0);
error:
@@ -181,6 +207,9 @@ error:
if (pipes[1] >= 0) close(pipes[1]);
if (pipes[2] >= 0) close(pipes[2]);
if (pipes[3] >= 0) close(pipes[3]);
+ if (handle && handle != MAP_FAILED)
+ munmap(handle, buflen);
+ handle = NULL;
}
static void /* attribute((destructor)) */ stop(void)
@@ -189,24 +218,24 @@ static void /* attribute((destructor)) *
kill(active, SIGKILL);
}
-static sigjmp_buf jenv;
-static void sigjump(int sig attribute((unused)))
-{
- siglongjmp(jenv, 1);
-}
-
/*
* External routine
+ *
+ * Execute stat(2) system call with timeout to avoid deadlock
+ * on network based file systems.
+ *
*/
-int timeout(stat_t function, const char *path, struct stat *restrict argument, time_t seconds)
+int
+timeout(stat_t function, const char *path, struct stat *restrict argument, time_t seconds)
{
- handle_t *restrict handle = (void*)&buf[0];
struct sigaction alrm_act, pipe_act, new_act;
sigset_t sigset, oldset;
+ char sync[1] = "x";
if (active <= 0) /* Oops, last one failed therefore clear status and restart */
start();
-
+ if (!handle) /* No shared memory area */
+ return function(path, argument);
memset(handle, 0, sizeof(handle_t));
handle->len = strlen(path) + 1;
if (handle->len >= PATH_MAX) {
@@ -235,8 +264,8 @@ int timeout(stat_t function, const char
sigaction(SIGPIPE, &new_act, &pipe_act);
alarm(seconds);
- write(pipes[1], handle, sizeof(handle_t)+handle->len);
- read(pipes[2], &handle->errcode, sizeof(handle->errcode)+sizeof(handle->argument));
+ write(pipes[1], &sync, sizeof(sync));
+ read(pipes[2], &sync, sizeof(sync));
alarm(0);
sigaction(SIGPIPE, &pipe_act, NULL);
@@ -261,6 +290,82 @@ timed:
error:
return -1;
}
+#elif WITH_TIMEOUT_STAT == 1
+/*
+ * External routine
+ *
+ * Execute stat(2) system call with timeout to avoid deadlock
+ * on network based file systems.
+ *
+ */
+int
+timeout(stat_t function, const char *path, struct stat *restrict argument, time_t seconds)
+{
+ struct sigaction alrm_act, pipe_act, new_act;
+ sigset_t sigset, oldset;
+ int ret = 0, pipes[4];
+ pid_t pid = 0;
+ ssize_t len;
+
+ if (pipe(&pipes[0]) < 0)
+ goto error;
+ switch ((pid = fork())) {
+ case -1:
+ close(pipes[0]);
+ close(pipes[1]);
+ goto error;
+ case 0:
+ new_act.sa_handler = SIG_DFL;
+ sigaction(SIGALRM, &new_act, NULL);
+ close(pipes[0]);
+ if ((ret = function(path, argument)) == 0)
+ do
+ len = write(pipes[1], argument, sizeof(struct stat));
+ while (len < 0 && errno == EINTR);
+ close(pipes[1]);
+ exit(ret);
+ default:
+ close(pipes[1]);
+
+ sigemptyset(&sigset);
+ sigaddset(&sigset, SIGALRM);
+ sigaddset(&sigset, SIGPIPE);
+ sigprocmask(SIG_UNBLOCK, &sigset, &oldset);
+
+ memset(&new_act, 0, sizeof(new_act));
+ sigemptyset(&new_act.sa_mask);
+
+ if (sigsetjmp(jenv, 1))
+ goto timed;
+
+ new_act.sa_handler = sigjump;
+ sigaction(SIGALRM, &new_act, &alrm_act);
+ sigaction(SIGPIPE, &new_act, &pipe_act);
+ alarm(seconds);
+ if (read(pipes[0], argument, sizeof(struct stat)) == 0) {
+ errno = EFAULT;
+ ret = -1;
+ }
+ (void)alarm(0);
+ sigaction(SIGPIPE, &pipe_act, NULL);
+ sigaction(SIGALRM, &alrm_act, NULL);
+
+ close(pipes[0]);
+ waitpid(pid, NULL, 0);
+ break;
+ }
+ return ret;
+timed:
+ (void)alarm(0);
+ sigaction(SIGPIPE, &pipe_act, NULL);
+ sigaction(SIGALRM, &alrm_act, NULL);
+ if (waitpid(0, NULL, WNOHANG) == 0)
+ kill(pid, SIGKILL);
+ errno = ETIMEDOUT;
+error:
+ return -1;
+}
+#endif
/*
* End of timeout.c
--- src/timeout.h
+++ src/timeout.h 2014-03-24 00:00:00.000000000 +0000
@@ -17,7 +17,11 @@
#ifndef _TIMEOUT_H
#define _TIMEOUT_H
-#include "config.h" /* For _FILE_OFFSET_BITS */
+#include "config.h"
+
+#ifndef WITH_TIMEOUT_STAT
+# define WITH_TIMEOUT_STAT 0
+#endif
#include <sys/types.h>
#include <sys/stat.h>
@@ -30,7 +34,12 @@
# endif
#endif
-typedef int (*stat_t)(const char *, struct stat *restrict);
+typedef int (*stat_t)(const char *, struct stat *);
+
+#if WITH_TIMEOUT_STAT > 0
extern int timeout(stat_t, const char *, struct stat *restrict, time_t);
+#else
+# define timeout(func,path,buf,dummy) (func)((path),(buf))
+#endif
#endif
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