1/*
2 * Helper functions for handling target threads/cpus
3 *
4 * Copyright (C) 2012, LG Electronics, Namhyung Kim <namhyung.kim@lge.com>
5 *
6 * Released under the GPL v2.
7 */
8
9#include "target.h"
10#include "debug.h"
11
12#include <pwd.h>
13#include <string.h>
14
15
16enum target_errno target__validate(struct target *target)
17{
18	enum target_errno ret = TARGET_ERRNO__SUCCESS;
19
20	if (target->pid)
21		target->tid = target->pid;
22
23	/* CPU and PID are mutually exclusive */
24	if (target->tid && target->cpu_list) {
25		target->cpu_list = NULL;
26		if (ret == TARGET_ERRNO__SUCCESS)
27			ret = TARGET_ERRNO__PID_OVERRIDE_CPU;
28	}
29
30	/* UID and PID are mutually exclusive */
31	if (target->tid && target->uid_str) {
32		target->uid_str = NULL;
33		if (ret == TARGET_ERRNO__SUCCESS)
34			ret = TARGET_ERRNO__PID_OVERRIDE_UID;
35	}
36
37	/* UID and CPU are mutually exclusive */
38	if (target->uid_str && target->cpu_list) {
39		target->cpu_list = NULL;
40		if (ret == TARGET_ERRNO__SUCCESS)
41			ret = TARGET_ERRNO__UID_OVERRIDE_CPU;
42	}
43
44	/* PID and SYSTEM are mutually exclusive */
45	if (target->tid && target->system_wide) {
46		target->system_wide = false;
47		if (ret == TARGET_ERRNO__SUCCESS)
48			ret = TARGET_ERRNO__PID_OVERRIDE_SYSTEM;
49	}
50
51	/* UID and SYSTEM are mutually exclusive */
52	if (target->uid_str && target->system_wide) {
53		target->system_wide = false;
54		if (ret == TARGET_ERRNO__SUCCESS)
55			ret = TARGET_ERRNO__UID_OVERRIDE_SYSTEM;
56	}
57
58	/* THREAD and SYSTEM/CPU are mutually exclusive */
59	if (target->per_thread && (target->system_wide || target->cpu_list)) {
60		target->per_thread = false;
61		if (ret == TARGET_ERRNO__SUCCESS)
62			ret = TARGET_ERRNO__SYSTEM_OVERRIDE_THREAD;
63	}
64
65	return ret;
66}
67
68enum target_errno target__parse_uid(struct target *target)
69{
70	struct passwd pwd, *result;
71	char buf[1024];
72	const char *str = target->uid_str;
73
74	target->uid = UINT_MAX;
75	if (str == NULL)
76		return TARGET_ERRNO__SUCCESS;
77
78	/* Try user name first */
79	getpwnam_r(str, &pwd, buf, sizeof(buf), &result);
80
81	if (result == NULL) {
82		/*
83		 * The user name not found. Maybe it's a UID number.
84		 */
85		char *endptr;
86		int uid = strtol(str, &endptr, 10);
87
88		if (*endptr != '\0')
89			return TARGET_ERRNO__INVALID_UID;
90
91		getpwuid_r(uid, &pwd, buf, sizeof(buf), &result);
92
93		if (result == NULL)
94			return TARGET_ERRNO__USER_NOT_FOUND;
95	}
96
97	target->uid = result->pw_uid;
98	return TARGET_ERRNO__SUCCESS;
99}
100
101/*
102 * This must have a same ordering as the enum target_errno.
103 */
104static const char *target__error_str[] = {
105	"PID/TID switch overriding CPU",
106	"PID/TID switch overriding UID",
107	"UID switch overriding CPU",
108	"PID/TID switch overriding SYSTEM",
109	"UID switch overriding SYSTEM",
110	"SYSTEM/CPU switch overriding PER-THREAD",
111	"Invalid User: %s",
112	"Problems obtaining information for user %s",
113};
114
115int target__strerror(struct target *target, int errnum,
116			  char *buf, size_t buflen)
117{
118	int idx;
119	const char *msg;
120
121	BUG_ON(buflen == 0);
122
123	if (errnum >= 0) {
124		const char *err = strerror_r(errnum, buf, buflen);
125
126		if (err != buf)
127			scnprintf(buf, buflen, "%s", err);
128
129		return 0;
130	}
131
132	if (errnum <  __TARGET_ERRNO__START || errnum >= __TARGET_ERRNO__END)
133		return -1;
134
135	idx = errnum - __TARGET_ERRNO__START;
136	msg = target__error_str[idx];
137
138	switch (errnum) {
139	case TARGET_ERRNO__PID_OVERRIDE_CPU ...
140	     TARGET_ERRNO__SYSTEM_OVERRIDE_THREAD:
141		snprintf(buf, buflen, "%s", msg);
142		break;
143
144	case TARGET_ERRNO__INVALID_UID:
145	case TARGET_ERRNO__USER_NOT_FOUND:
146		snprintf(buf, buflen, msg, target->uid_str);
147		break;
148
149	default:
150		/* cannot reach here */
151		break;
152	}
153
154	return 0;
155}
156