xref: /openbmc/linux/tools/perf/util/target.c (revision 0da85d1e)
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 
16 enum 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 
68 enum 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  */
104 static 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 
115 int 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