diff --git a/include/crm/common/internal.h b/include/crm/common/internal.h
index aed8daf499..76c8537e5c 100644
--- a/include/crm/common/internal.h
+++ b/include/crm/common/internal.h
@@ -1,403 +1,404 @@
/*
* Copyright 2015-2022 the Pacemaker project contributors
*
* The version control history for this file may have further details.
*
* This source code is licensed under the GNU Lesser General Public License
* version 2.1 or later (LGPLv2.1+) WITHOUT ANY WARRANTY.
*/
#ifndef CRM_COMMON_INTERNAL__H
#define CRM_COMMON_INTERNAL__H
#include <unistd.h> // getpid()
#include <stdbool.h> // bool
#include <stdint.h> // uint8_t, uint64_t
#include <string.h> // strcmp()
#include <fcntl.h> // open()
#include <sys/types.h> // uid_t, gid_t, pid_t
#include <glib.h> // guint, GList, GHashTable
#include <libxml/tree.h> // xmlNode
#include <crm/common/util.h> // crm_strdup_printf()
#include <crm/common/logging.h> // do_crm_log_unlikely(), etc.
#include <crm/common/mainloop.h> // mainloop_io_t, struct ipc_client_callbacks
#include <crm/common/health_internal.h>
#include <crm/common/iso8601_internal.h>
#include <crm/common/results_internal.h>
#include <crm/common/messages_internal.h>
#include <crm/common/strings_internal.h>
/* This says whether the current application is a Pacemaker daemon or not,
* and is used to change default logging settings such as whether to log to
* stderr, etc., as well as a few other details such as whether blackbox signal
* handling is enabled.
*
* It is set when logging is initialized, and does not need to be set directly.
*/
extern bool pcmk__is_daemon;
// Number of elements in a statically defined array
#define PCMK__NELEM(a) ((int) (sizeof(a)/sizeof(a[0])) )
/* internal ACL-related utilities */
char *pcmk__uid2username(uid_t uid);
const char *pcmk__update_acl_user(xmlNode *request, const char *field,
const char *peer_user);
static inline bool
pcmk__is_privileged(const char *user)
{
return user && (!strcmp(user, CRM_DAEMON_USER) || !strcmp(user, "root"));
}
void pcmk__enable_acl(xmlNode *acl_source, xmlNode *target, const char *user);
bool pcmk__check_acl(xmlNode *xml, const char *name,
enum xml_private_flags mode);
#if SUPPORT_CIBSECRETS
/* internal CIB utilities (from cib_secrets.c) */
int pcmk__substitute_secrets(const char *rsc_id, GHashTable *params);
#endif
/* internal digest-related utilities (from digest.c) */
bool pcmk__verify_digest(xmlNode *input, const char *expected);
/* internal I/O utilities (from io.c) */
int pcmk__real_path(const char *path, char **resolved_path);
char *pcmk__series_filename(const char *directory, const char *series,
int sequence, bool bzip);
int pcmk__read_series_sequence(const char *directory, const char *series,
unsigned int *seq);
void pcmk__write_series_sequence(const char *directory, const char *series,
unsigned int sequence, int max);
int pcmk__chown_series_sequence(const char *directory, const char *series,
uid_t uid, gid_t gid);
int pcmk__build_path(const char *path_c, mode_t mode);
char *pcmk__full_path(const char *filename, const char *dirname);
bool pcmk__daemon_can_write(const char *dir, const char *file);
void pcmk__sync_directory(const char *name);
int pcmk__file_contents(const char *filename, char **contents);
int pcmk__write_sync(int fd, const char *contents);
int pcmk__set_nonblocking(int fd);
const char *pcmk__get_tmpdir(void);
void pcmk__close_fds_in_child(bool);
/*!
* \internal
* \brief Open /dev/null to consume next available file descriptor
*
* Open /dev/null, disregarding the result. This is intended when daemonizing to
* be able to null stdin, stdout, and stderr.
*
* \param[in] flags O_RDONLY (stdin) or O_WRONLY (stdout and stderr)
*/
static inline void
pcmk__open_devnull(int flags)
{
// Static analysis clutter
// cppcheck-suppress leakReturnValNotUsed
(void) open("/dev/null", flags);
}
/* internal main loop utilities (from mainloop.c) */
int pcmk__add_mainloop_ipc(crm_ipc_t *ipc, int priority, void *userdata,
struct ipc_client_callbacks *callbacks,
mainloop_io_t **source);
guint pcmk__mainloop_timer_get_period(mainloop_timer_t *timer);
/* internal name/value utilities (from nvpair.c) */
int pcmk__scan_nvpair(const char *input, char **name, char **value);
char *pcmk__format_nvpair(const char *name, const char *value,
const char *units);
char *pcmk__format_named_time(const char *name, time_t epoch_time);
/*!
* \internal
* \brief Add a boolean attribute to an XML node.
*
* \param[in,out] node XML node to add attributes to
* \param[in] name XML attribute to create
* \param[in] value Value to give to the attribute
*/
void
pcmk__xe_set_bool_attr(xmlNodePtr node, const char *name, bool value);
/*!
* \internal
* \brief Extract a boolean attribute's value from an XML element
*
* \param[in] node XML node to get attribute from
* \param[in] name XML attribute to get
*
* \return True if the given \p name is an attribute on \p node and has
* the value "true", False in all other cases
*/
bool
pcmk__xe_attr_is_true(xmlNodePtr node, const char *name);
/*!
* \internal
* \brief Extract a boolean attribute's value from an XML element, with
* error checking
*
* \param[in] node XML node to get attribute from
* \param[in] name XML attribute to get
* \param[out] value Destination for the value of the attribute
*
* \return EINVAL if \p name or \p value are NULL, ENODATA if \p node is
* NULL or the attribute does not exist, pcmk_rc_unknown_format
* if the attribute is not a boolean, and pcmk_rc_ok otherwise.
*
* \note \p value only has any meaning if the return value is pcmk_rc_ok.
*/
int
pcmk__xe_get_bool_attr(xmlNodePtr node, const char *name, bool *value);
/* internal procfs utilities (from procfs.c) */
pid_t pcmk__procfs_pid_of(const char *name);
unsigned int pcmk__procfs_num_cores(void);
int pcmk__procfs_pid2path(pid_t pid, char path[], size_t path_size);
+bool pcmk__procfs_has_pids(void);
/* internal XML schema functions (from xml.c) */
void crm_schema_init(void);
void crm_schema_cleanup(void);
/* internal functions related to process IDs (from pid.c) */
/*!
* \internal
* \brief Check whether process exists (by PID and optionally executable path)
*
* \param[in] pid PID of process to check
* \param[in] daemon If not NULL, path component to match with procfs entry
*
* \return Standard Pacemaker return code
* \note Particular return codes of interest include pcmk_rc_ok for alive,
* ESRCH for process is not alive (verified by kill and/or executable path
* match), EACCES for caller unable or not allowed to check. A result of
* "alive" is less reliable when \p daemon is not provided or procfs is
* not available, since there is no guarantee that the PID has not been
* recycled for another process.
* \note This function cannot be used to verify \e authenticity of the process.
*/
int pcmk__pid_active(pid_t pid, const char *daemon);
int pcmk__read_pidfile(const char *filename, pid_t *pid);
int pcmk__pidfile_matches(const char *filename, pid_t expected_pid,
const char *expected_name, pid_t *pid);
int pcmk__lock_pidfile(const char *filename, const char *name);
/* internal functions related to resource operations (from operations.c) */
// printf-style format to create operation ID from resource, action, interval
#define PCMK__OP_FMT "%s_%s_%u"
char *pcmk__op_key(const char *rsc_id, const char *op_type, guint interval_ms);
char *pcmk__notify_key(const char *rsc_id, const char *notify_type,
const char *op_type);
char *pcmk__transition_key(int transition_id, int action_id, int target_rc,
const char *node);
void pcmk__filter_op_for_digest(xmlNode *param_set);
bool pcmk__is_fencing_action(const char *action);
// bitwise arithmetic utilities
/*!
* \internal
* \brief Set specified flags in a flag group
*
* \param[in] function Function name of caller
* \param[in] line Line number of caller
* \param[in] log_level Log a message at this level
* \param[in] flag_type Label describing this flag group (for logging)
* \param[in] target Name of object whose flags these are (for logging)
* \param[in] flag_group Flag group being manipulated
* \param[in] flags Which flags in the group should be set
* \param[in] flags_str Readable equivalent of \p flags (for logging)
*
* \return Possibly modified flag group
*/
static inline uint64_t
pcmk__set_flags_as(const char *function, int line, uint8_t log_level,
const char *flag_type, const char *target,
uint64_t flag_group, uint64_t flags, const char *flags_str)
{
uint64_t result = flag_group | flags;
if (result != flag_group) {
do_crm_log_unlikely(log_level,
"%s flags %#.8llx (%s) for %s set by %s:%d",
((flag_type == NULL)? "Group of" : flag_type),
(unsigned long long) flags,
((flags_str == NULL)? "flags" : flags_str),
((target == NULL)? "target" : target),
function, line);
}
return result;
}
/*!
* \internal
* \brief Clear specified flags in a flag group
*
* \param[in] function Function name of caller
* \param[in] line Line number of caller
* \param[in] log_level Log a message at this level
* \param[in] flag_type Label describing this flag group (for logging)
* \param[in] target Name of object whose flags these are (for logging)
* \param[in] flag_group Flag group being manipulated
* \param[in] flags Which flags in the group should be cleared
* \param[in] flags_str Readable equivalent of \p flags (for logging)
*
* \return Possibly modified flag group
*/
static inline uint64_t
pcmk__clear_flags_as(const char *function, int line, uint8_t log_level,
const char *flag_type, const char *target,
uint64_t flag_group, uint64_t flags, const char *flags_str)
{
uint64_t result = flag_group & ~flags;
if (result != flag_group) {
do_crm_log_unlikely(log_level,
"%s flags %#.8llx (%s) for %s cleared by %s:%d",
((flag_type == NULL)? "Group of" : flag_type),
(unsigned long long) flags,
((flags_str == NULL)? "flags" : flags_str),
((target == NULL)? "target" : target),
function, line);
}
return result;
}
// miscellaneous utilities (from utils.c)
void pcmk__daemonize(const char *name, const char *pidfile);
void pcmk__panic(const char *origin);
pid_t pcmk__locate_sbd(void);
void pcmk__sleep_ms(unsigned int ms);
extern int pcmk__score_red;
extern int pcmk__score_green;
extern int pcmk__score_yellow;
/*!
* \internal
* \brief Resize a dynamically allocated memory block
*
* \param[in] ptr Memory block to resize (or NULL to allocate new memory)
* \param[in] size New size of memory block in bytes (must be > 0)
*
* \return Pointer to resized memory block
*
* \note This asserts on error, so the result is guaranteed to be non-NULL
* (which is the main advantage of this over directly using realloc()).
*/
static inline void *
pcmk__realloc(void *ptr, size_t size)
{
void *new_ptr;
// realloc(p, 0) can replace free(p) but this wrapper can't
CRM_ASSERT(size > 0);
new_ptr = realloc(ptr, size);
if (new_ptr == NULL) {
free(ptr);
abort();
}
return new_ptr;
}
static inline char *
pcmk__getpid_s(void)
{
return crm_strdup_printf("%lu", (unsigned long) getpid());
}
// More efficient than g_list_length(list) == 1
static inline bool
pcmk__list_of_1(GList *list)
{
return list && (list->next == NULL);
}
// More efficient than g_list_length(list) > 1
static inline bool
pcmk__list_of_multiple(GList *list)
{
return list && (list->next != NULL);
}
/* convenience functions for failure-related node attributes */
#define PCMK__FAIL_COUNT_PREFIX "fail-count"
#define PCMK__LAST_FAILURE_PREFIX "last-failure"
/*!
* \internal
* \brief Generate a failure-related node attribute name for a resource
*
* \param[in] prefix Start of attribute name
* \param[in] rsc_id Resource name
* \param[in] op Operation name
* \param[in] interval_ms Operation interval
*
* \return Newly allocated string with attribute name
*
* \note Failure attributes are named like PREFIX-RSC#OP_INTERVAL (for example,
* "fail-count-myrsc#monitor_30000"). The '#' is used because it is not
* a valid character in a resource ID, to reliably distinguish where the
* operation name begins. The '_' is used simply to be more comparable to
* action labels like "myrsc_monitor_30000".
*/
static inline char *
pcmk__fail_attr_name(const char *prefix, const char *rsc_id, const char *op,
guint interval_ms)
{
CRM_CHECK(prefix && rsc_id && op, return NULL);
return crm_strdup_printf("%s-%s#%s_%u", prefix, rsc_id, op, interval_ms);
}
static inline char *
pcmk__failcount_name(const char *rsc_id, const char *op, guint interval_ms)
{
return pcmk__fail_attr_name(PCMK__FAIL_COUNT_PREFIX, rsc_id, op,
interval_ms);
}
static inline char *
pcmk__lastfailure_name(const char *rsc_id, const char *op, guint interval_ms)
{
return pcmk__fail_attr_name(PCMK__LAST_FAILURE_PREFIX, rsc_id, op,
interval_ms);
}
// internal resource agent functions (from agents.c)
int pcmk__effective_rc(int rc);
#endif /* CRM_COMMON_INTERNAL__H */
diff --git a/lib/common/pid.c b/lib/common/pid.c
index fab49ceea6..b9749c6b76 100644
--- a/lib/common/pid.c
+++ b/lib/common/pid.c
@@ -1,256 +1,240 @@
/*
* Copyright 2004-2022 the Pacemaker project contributors
*
* The version control history for this file may have further details.
*
* This source code is licensed under the GNU Lesser General Public License
* version 2.1 or later (LGPLv2.1+) WITHOUT ANY WARRANTY.
*/
#include <crm_internal.h>
#ifndef _GNU_SOURCE
# define _GNU_SOURCE
#endif
#include <stdio.h>
#include <string.h>
#include <sys/stat.h>
#include <crm/crm.h>
int
pcmk__pid_active(pid_t pid, const char *daemon)
{
static pid_t last_asked_pid = 0; /* log spam prevention */
-#if SUPPORT_PROCFS
- static int have_proc_pid = 0;
-#else
- static int have_proc_pid = -1;
-#endif
int rc = 0;
- if (have_proc_pid == 0) {
- /* evaluation of /proc/PID/exe applicability via self-introspection */
- char path[PATH_MAX];
-
- if (pcmk__procfs_pid2path(getpid(), path, sizeof(path)) == pcmk_rc_ok) {
- have_proc_pid = 1;
- } else {
- have_proc_pid = -1;
- }
- }
-
if (pid <= 0) {
return EINVAL;
}
rc = kill(pid, 0);
if ((rc < 0) && (errno == ESRCH)) {
return ESRCH; /* no such PID detected */
- } else if ((daemon == NULL) || (have_proc_pid == -1)) {
+ } else if ((daemon == NULL) || !pcmk__procfs_has_pids()) {
// The kill result is all we have, we can't check the name
if (rc == 0) {
return pcmk_rc_ok;
}
rc = errno;
if (last_asked_pid != pid) {
crm_info("Cannot examine PID %lld: %s",
(long long) pid, pcmk_rc_str(rc));
last_asked_pid = pid;
}
return rc; /* errno != ESRCH */
} else {
/* make sure PID hasn't been reused by another process
XXX: might still be just a zombie, which could confuse decisions */
bool checked_through_kill = (rc == 0);
char exe_path[PATH_MAX], myexe_path[PATH_MAX];
rc = pcmk__procfs_pid2path(pid, exe_path, sizeof(exe_path));
if (rc != pcmk_rc_ok) {
if (rc != EACCES) {
// Check again to filter out races
if ((kill(pid, 0) < 0) && (errno == ESRCH)) {
return ESRCH;
}
}
if (last_asked_pid != pid) {
if (rc == EACCES) {
crm_info("Could not get executable for PID %lld: %s "
CRM_XS " rc=%d",
(long long) pid, pcmk_rc_str(rc), rc);
} else {
crm_err("Could not get executable for PID %lld: %s "
CRM_XS " rc=%d",
(long long) pid, pcmk_rc_str(rc), rc);
}
last_asked_pid = pid;
}
if (rc == EACCES) {
// Trust kill if it was OK (we can't double-check via path)
return checked_through_kill? pcmk_rc_ok : EACCES;
} else {
return ESRCH; /* most likely errno == ENOENT */
}
}
if (daemon[0] != '/') {
rc = snprintf(myexe_path, sizeof(myexe_path), CRM_DAEMON_DIR"/%s",
daemon);
} else {
rc = snprintf(myexe_path, sizeof(myexe_path), "%s", daemon);
}
if (rc > 0 && rc < sizeof(myexe_path) && !strcmp(exe_path, myexe_path)) {
return pcmk_rc_ok;
}
}
return ESRCH;
}
#define LOCKSTRLEN 11
/*!
* \internal
* \brief Read a process ID from a file
*
* \param[in] filename Process ID file to read
* \param[out] pid Where to put PID that was read
*
* \return Standard Pacemaker return code
*/
int
pcmk__read_pidfile(const char *filename, pid_t *pid)
{
int fd;
struct stat sbuf;
int rc = pcmk_rc_unknown_format;
long long pid_read = 0;
char buf[LOCKSTRLEN + 1];
CRM_CHECK((filename != NULL) && (pid != NULL), return EINVAL);
fd = open(filename, O_RDONLY);
if (fd < 0) {
return errno;
}
if ((fstat(fd, &sbuf) >= 0) && (sbuf.st_size < LOCKSTRLEN)) {
sleep(2); /* if someone was about to create one,
* give'm a sec to do so
*/
}
if (read(fd, buf, sizeof(buf)) < 1) {
rc = errno;
goto bail;
}
if (sscanf(buf, "%lld", &pid_read) > 0) {
if (pid_read <= 0) {
rc = ESRCH;
} else {
rc = pcmk_rc_ok;
*pid = (pid_t) pid_read;
crm_trace("Read pid %lld from %s", pid_read, filename);
}
}
bail:
close(fd);
return rc;
}
/*!
* \internal
* \brief Check whether a process from a PID file matches expected values
*
* \param[in] filename Path of PID file
* \param[in] expected_pid If positive, compare to this PID
* \param[in] expected_name If not NULL, the PID from the PID file is valid
* only if it is active as a process with this name
* \param[out] pid If not NULL, store PID found in PID file here
*
* \return Standard Pacemaker return code
*/
int
pcmk__pidfile_matches(const char *filename, pid_t expected_pid,
const char *expected_name, pid_t *pid)
{
pid_t pidfile_pid = 0;
int rc = pcmk__read_pidfile(filename, &pidfile_pid);
if (pid) {
*pid = pidfile_pid;
}
if (rc != pcmk_rc_ok) {
// Error reading PID file or invalid contents
unlink(filename);
rc = ENOENT;
} else if ((expected_pid > 0) && (pidfile_pid == expected_pid)) {
// PID in file matches what was expected
rc = pcmk_rc_ok;
} else if (pcmk__pid_active(pidfile_pid, expected_name) == ESRCH) {
// Contains a stale value
unlink(filename);
rc = ENOENT;
} else if ((expected_pid > 0) && (pidfile_pid != expected_pid)) {
// Locked by existing process
rc = EEXIST;
}
return rc;
}
/*!
* \internal
* \brief Create a PID file for the current process (if not already existent)
*
* \param[in] filename Name of PID file to create
* \param[in] name Name of current process
*
* \return Standard Pacemaker return code
*/
int
pcmk__lock_pidfile(const char *filename, const char *name)
{
pid_t mypid = getpid();
int fd = 0;
int rc = 0;
char buf[LOCKSTRLEN + 2];
rc = pcmk__pidfile_matches(filename, 0, name, NULL);
if ((rc != pcmk_rc_ok) && (rc != ENOENT)) {
// Locked by existing process
return rc;
}
fd = open(filename, O_CREAT | O_WRONLY | O_EXCL, 0644);
if (fd < 0) {
return errno;
}
snprintf(buf, sizeof(buf), "%*lld\n", LOCKSTRLEN - 1, (long long) mypid);
rc = write(fd, buf, LOCKSTRLEN);
close(fd);
if (rc != LOCKSTRLEN) {
crm_perror(LOG_ERR, "Incomplete write to %s", filename);
return errno;
}
rc = pcmk__pidfile_matches(filename, mypid, name, NULL);
if (rc != pcmk_rc_ok) {
// Something is really wrong -- maybe I/O error on read back?
unlink(filename);
}
return rc;
}
diff --git a/lib/common/procfs.c b/lib/common/procfs.c
index 01fb2b689e..37ab62b428 100644
--- a/lib/common/procfs.c
+++ b/lib/common/procfs.c
@@ -1,202 +1,227 @@
/*
* Copyright 2015-2022 the Pacemaker project contributors
*
* The version control history for this file may have further details.
*
* This source code is licensed under the GNU Lesser General Public License
* version 2.1 or later (LGPLv2.1+) WITHOUT ANY WARRANTY.
*/
#include <crm_internal.h>
#ifndef _GNU_SOURCE
# define _GNU_SOURCE
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <dirent.h>
#include <ctype.h>
/*!
* \internal
* \brief Get process ID and name associated with a /proc directory entry
*
* \param[in] entry Directory entry (must be result of readdir() on /proc)
* \param[out] name If not NULL, a char[16] to hold the process name
* \param[out] pid If not NULL, will be set to process ID of entry
*
* \return Standard Pacemaker return code
* \note This should be called only on Linux systems, as not all systems that
* support /proc store process names and IDs in the same way. The kernel
* limits the process name to the first 15 characters (plus terminator).
* It would be nice if there were a public kernel API constant for that
* limit, but there isn't.
*/
static int
pcmk__procfs_process_info(struct dirent *entry, char *name, pid_t *pid)
{
int fd, local_pid;
FILE *file;
struct stat statbuf;
char procpath[128] = { 0 };
/* We're only interested in entries whose name is a PID,
* so skip anything non-numeric or that is too long.
*
* 114 = 128 - strlen("/proc/") - strlen("/status") - 1
*/
local_pid = atoi(entry->d_name);
if ((local_pid <= 0) || (strlen(entry->d_name) > 114)) {
return -1;
}
if (pid) {
*pid = (pid_t) local_pid;
}
/* Get this entry's file information */
strcpy(procpath, "/proc/");
strcat(procpath, entry->d_name);
fd = open(procpath, O_RDONLY);
if (fd < 0 ) {
return -1;
}
if (fstat(fd, &statbuf) < 0) {
close(fd);
return -1;
}
close(fd);
/* We're only interested in subdirectories */
if (!S_ISDIR(statbuf.st_mode)) {
return -1;
}
/* Read the first entry ("Name:") from the process's status file.
* We could handle the valgrind case if we parsed the cmdline file
* instead, but that's more of a pain than it's worth.
*/
if (name != NULL) {
strcat(procpath, "/status");
file = fopen(procpath, "r");
if (!file) {
return -1;
}
if (fscanf(file, "Name:\t%15[^\n]", name) != 1) {
fclose(file);
return -1;
}
name[15] = 0;
fclose(file);
}
return 0;
}
/*!
* \internal
* \brief Return process ID of a named process
*
* \param[in] name Process name (as used in /proc/.../status)
*
* \return Process ID of named process if running, 0 otherwise
*
* \note This will return 0 if the process is being run via valgrind.
* This should be called only on Linux systems.
*/
pid_t
pcmk__procfs_pid_of(const char *name)
{
DIR *dp;
struct dirent *entry;
pid_t pid = 0;
char entry_name[64] = { 0 };
dp = opendir("/proc");
if (dp == NULL) {
crm_notice("Can not read /proc directory to track existing components");
return 0;
}
while ((entry = readdir(dp)) != NULL) {
if ((pcmk__procfs_process_info(entry, entry_name, &pid) == pcmk_rc_ok)
&& pcmk__str_eq(entry_name, name, pcmk__str_casei)
&& (pcmk__pid_active(pid, NULL) == pcmk_rc_ok)) {
crm_info("Found %s active as process %lld", name, (long long) pid);
break;
}
pid = 0;
}
closedir(dp);
return pid;
}
/*!
* \internal
* \brief Calculate number of logical CPU cores from procfs
*
* \return Number of cores (or 1 if unable to determine)
*/
unsigned int
pcmk__procfs_num_cores(void)
{
int cores = 0;
FILE *stream = NULL;
/* Parse /proc/stat instead of /proc/cpuinfo because it's smaller */
stream = fopen("/proc/stat", "r");
if (stream == NULL) {
crm_perror(LOG_INFO, "Could not open /proc/stat");
} else {
char buffer[2048];
while (fgets(buffer, sizeof(buffer), stream)) {
if (pcmk__starts_with(buffer, "cpu") && isdigit(buffer[3])) {
++cores;
}
}
fclose(stream);
}
return cores? cores : 1;
}
/*!
* \internal
* \brief Get the executable path corresponding to a process ID
*
* \param[in] pid Process ID to check
* \param[out] path Where to store executable path
* \param[in] path_size Size of \p path in characters (ideally PATH_MAX)
*
* \return Standard Pacemaker error code (as possible errno values from
* readlink())
*/
int
pcmk__procfs_pid2path(pid_t pid, char path[], size_t path_size)
{
#if SUPPORT_PROCFS
char procfs_exe_path[PATH_MAX];
ssize_t link_rc;
if (snprintf(procfs_exe_path, path_size, "/proc/%lld/exe",
(long long) pid) >= path_size) {
return ENAMETOOLONG; // Truncated (shouldn't be possible in practice)
}
link_rc = readlink(procfs_exe_path, path, path_size - 1);
if (link_rc < 0) {
return errno;
} else if (link_rc >= (path_size - 1)) {
return ENAMETOOLONG;
}
path[link_rc] = '\0';
return pcmk_rc_ok;
#else
return EOPNOTSUPP;
#endif
}
+
+/*!
+ * \internal
+ * \brief Check whether process ID information is available from procfs
+ *
+ * \return true if process ID information is available, otherwise false
+ */
+bool
+pcmk__procfs_has_pids(void)
+{
+#if SUPPORT_PROCFS
+ static bool have_pids = false;
+ static bool checked = false;
+
+ if (!checked) {
+ char path[PATH_MAX];
+
+ have_pids = pcmk__procfs_pid2path(getpid(), path, sizeof(path)) == pcmk_rc_ok;
+ checked = true;
+ }
+ return have_pids;
+#else
+ return false;
+#endif
+}