summaryrefslogtreecommitdiff
path: root/tools/perf/util/target.c
blob: a3db13dea937cc40061bff4a3bc29e6b45089a61 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Helper functions for handling target threads/cpus
 *
 * Copyright (C) 2012, LG Electronics, Namhyung Kim <namhyung.kim@lge.com>
 */

#include "target.h"

#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <linux/kernel.h>
#include <linux/string.h>

enum target_errno target__validate(struct target *target)
{
	enum target_errno ret = TARGET_ERRNO__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 == TARGET_ERRNO__SUCCESS)
			ret = TARGET_ERRNO__PID_OVERRIDE_CPU;
	}

	/* UID and PID are mutually exclusive */
	if (target->tid && target->uid_str) {
		target->uid_str = NULL;
		if (ret == TARGET_ERRNO__SUCCESS)
			ret = TARGET_ERRNO__PID_OVERRIDE_UID;
	}

	/* UID and CPU are mutually exclusive */
	if (target->uid_str && target->cpu_list) {
		target->cpu_list = NULL;
		if (ret == TARGET_ERRNO__SUCCESS)
			ret = TARGET_ERRNO__UID_OVERRIDE_CPU;
	}

	/* PID and SYSTEM are mutually exclusive */
	if (target->tid && target->system_wide) {
		target->system_wide = false;
		if (ret == TARGET_ERRNO__SUCCESS)
			ret = TARGET_ERRNO__PID_OVERRIDE_SYSTEM;
	}

	/* UID and SYSTEM are mutually exclusive */
	if (target->uid_str && target->system_wide) {
		target->system_wide = false;
		if (ret == TARGET_ERRNO__SUCCESS)
			ret = TARGET_ERRNO__UID_OVERRIDE_SYSTEM;
	}

	/* THREAD and SYSTEM/CPU are mutually exclusive */
	if (target->per_thread && (target->system_wide || target->cpu_list)) {
		target->per_thread = false;
		if (ret == TARGET_ERRNO__SUCCESS)
			ret = TARGET_ERRNO__SYSTEM_OVERRIDE_THREAD;
	}

	return ret;
}

enum target_errno target__parse_uid(struct target *target)
{
	struct passwd pwd, *result;
	char buf[1024];
	const char *str = target->uid_str;

	target->uid = UINT_MAX;
	if (str == NULL)
		return TARGET_ERRNO__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 TARGET_ERRNO__INVALID_UID;

		getpwuid_r(uid, &pwd, buf, sizeof(buf), &result);

		if (result == NULL)
			return TARGET_ERRNO__USER_NOT_FOUND;
	}

	target->uid = result->pw_uid;
	return TARGET_ERRNO__SUCCESS;
}

/*
 * This must have a same ordering as the enum target_errno.
 */
static const char *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",
	"SYSTEM/CPU switch overriding PER-THREAD",
	"Invalid User: %s",
	"Problems obtaining information for user %s",
};

int target__strerror(struct target *target, int errnum,
			  char *buf, size_t buflen)
{
	int idx;
	const char *msg;

	BUG_ON(buflen == 0);

	if (errnum >= 0) {
		str_error_r(errnum, buf, buflen);
		return 0;
	}

	if (errnum <  __TARGET_ERRNO__START || errnum >= __TARGET_ERRNO__END)
		return -1;

	idx = errnum - __TARGET_ERRNO__START;
	msg = target__error_str[idx];

	switch (errnum) {
	case TARGET_ERRNO__PID_OVERRIDE_CPU ...
	     TARGET_ERRNO__SYSTEM_OVERRIDE_THREAD:
		snprintf(buf, buflen, "%s", msg);
		break;

	case TARGET_ERRNO__INVALID_UID:
	case TARGET_ERRNO__USER_NOT_FOUND:
		snprintf(buf, buflen, msg, target->uid_str);
		break;

	default:
		/* cannot reach here */
		break;
	}

	return 0;
}