linux/tools/perf/util/target.c
Namhyung Kim 16ad2ffb82 perf tools: Introduce perf_target__strerror()
The perf_target__strerror() sets @buf to a string that describes the
(perf_target-specific) error condition that is passed via @errnum.

This is similar to strerror_r() and does same thing if @errnum has a
standard errno value.

Signed-off-by: Namhyung Kim <namhyung.kim@lge.com>
Suggested-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Reviewed-by: David Ahern <dsahern@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1336367344-28071-6-git-send-email-namhyung.kim@lge.com
[ committer note: No need to use PERF_ERRNO_TARGET__SUCCESS, use shorter idiom ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-05-07 17:30:21 -03:00

143 lines
3.2 KiB
C

/*
* Helper functions for handling target threads/cpus
*
* Copyright (C) 2012, LG Electronics, Namhyung Kim <namhyung.kim@lge.com>
*
* Released under the GPL v2.
*/
#include "target.h"
#include "debug.h"
#include <pwd.h>
#include <string.h>
enum perf_target_errno perf_target__validate(struct perf_target *target)
{
enum perf_target_errno ret = PERF_ERRNO_TARGET__SUCCESS;
if (target->pid)
target->tid = target->pid;
/* CPU and PID are mutually exclusive */
if (target->tid && target->cpu_list) {
target->cpu_list = NULL;
if (ret == PERF_ERRNO_TARGET__SUCCESS)
ret = PERF_ERRNO_TARGET__PID_OVERRIDE_CPU;
}
/* UID and PID are mutually exclusive */
if (target->tid && target->uid_str) {
target->uid_str = NULL;
if (ret == PERF_ERRNO_TARGET__SUCCESS)
ret = PERF_ERRNO_TARGET__PID_OVERRIDE_UID;
}
/* UID and CPU are mutually exclusive */
if (target->uid_str && target->cpu_list) {
target->cpu_list = NULL;
if (ret == PERF_ERRNO_TARGET__SUCCESS)
ret = PERF_ERRNO_TARGET__UID_OVERRIDE_CPU;
}
/* PID and SYSTEM are mutually exclusive */
if (target->tid && target->system_wide) {
target->system_wide = false;
if (ret == PERF_ERRNO_TARGET__SUCCESS)
ret = PERF_ERRNO_TARGET__PID_OVERRIDE_SYSTEM;
}
/* UID and SYSTEM are mutually exclusive */
if (target->uid_str && target->system_wide) {
target->system_wide = false;
if (ret == PERF_ERRNO_TARGET__SUCCESS)
ret = PERF_ERRNO_TARGET__UID_OVERRIDE_SYSTEM;
}
return ret;
}
enum perf_target_errno perf_target__parse_uid(struct perf_target *target)
{
struct passwd pwd, *result;
char buf[1024];
const char *str = target->uid_str;
target->uid = UINT_MAX;
if (str == NULL)
return PERF_ERRNO_TARGET__SUCCESS;
/* Try user name first */
getpwnam_r(str, &pwd, buf, sizeof(buf), &result);
if (result == NULL) {
/*
* The user name not found. Maybe it's a UID number.
*/
char *endptr;
int uid = strtol(str, &endptr, 10);
if (*endptr != '\0')
return PERF_ERRNO_TARGET__INVALID_UID;
getpwuid_r(uid, &pwd, buf, sizeof(buf), &result);
if (result == NULL)
return PERF_ERRNO_TARGET__USER_NOT_FOUND;
}
target->uid = result->pw_uid;
return PERF_ERRNO_TARGET__SUCCESS;
}
/*
* This must have a same ordering as the enum perf_target_errno.
*/
static const char *perf_target__error_str[] = {
"PID/TID switch overriding CPU",
"PID/TID switch overriding UID",
"UID switch overriding CPU",
"PID/TID switch overriding SYSTEM",
"UID switch overriding SYSTEM",
"Invalid User: %s",
"Problems obtaining information for user %s",
};
int perf_target__strerror(struct perf_target *target, int errnum,
char *buf, size_t buflen)
{
int idx;
const char *msg;
if (errnum >= 0) {
strerror_r(errnum, buf, buflen);
return 0;
}
if (errnum < __PERF_ERRNO_TARGET__START ||
errnum >= __PERF_ERRNO_TARGET__END)
return -1;
idx = errnum - __PERF_ERRNO_TARGET__START;
msg = perf_target__error_str[idx];
switch (errnum) {
case PERF_ERRNO_TARGET__PID_OVERRIDE_CPU
... PERF_ERRNO_TARGET__UID_OVERRIDE_SYSTEM:
snprintf(buf, buflen, "%s", msg);
break;
case PERF_ERRNO_TARGET__INVALID_UID:
case PERF_ERRNO_TARGET__USER_NOT_FOUND:
snprintf(buf, buflen, msg, target->uid_str);
break;
default:
/* cannot reach here */
break;
}
return 0;
}