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}