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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Helper functions for handling target threads/cpus4 *5 * Copyright (C) 2012, LG Electronics, Namhyung Kim <namhyung.kim@lge.com>6 */7 8#include "target.h"9 10#include <pwd.h>11#include <stdio.h>12#include <stdlib.h>13#include <string.h>14#include <linux/kernel.h>15#include <linux/string.h>16 17enum target_errno target__validate(struct target *target)18{19 enum target_errno ret = TARGET_ERRNO__SUCCESS;20 21 if (target->pid)22 target->tid = target->pid;23 24 /* CPU and PID are mutually exclusive */25 if (target->tid && target->cpu_list) {26 target->cpu_list = NULL;27 if (ret == TARGET_ERRNO__SUCCESS)28 ret = TARGET_ERRNO__PID_OVERRIDE_CPU;29 }30 31 /* UID and PID are mutually exclusive */32 if (target->tid && target->uid_str) {33 target->uid_str = NULL;34 if (ret == TARGET_ERRNO__SUCCESS)35 ret = TARGET_ERRNO__PID_OVERRIDE_UID;36 }37 38 /* UID and CPU are mutually exclusive */39 if (target->uid_str && target->cpu_list) {40 target->cpu_list = NULL;41 if (ret == TARGET_ERRNO__SUCCESS)42 ret = TARGET_ERRNO__UID_OVERRIDE_CPU;43 }44 45 /* PID and SYSTEM are mutually exclusive */46 if (target->tid && target->system_wide) {47 target->system_wide = false;48 if (ret == TARGET_ERRNO__SUCCESS)49 ret = TARGET_ERRNO__PID_OVERRIDE_SYSTEM;50 }51 52 /* UID and SYSTEM are mutually exclusive */53 if (target->uid_str && target->system_wide) {54 target->system_wide = false;55 if (ret == TARGET_ERRNO__SUCCESS)56 ret = TARGET_ERRNO__UID_OVERRIDE_SYSTEM;57 }58 59 /* BPF and CPU are mutually exclusive */60 if (target->bpf_str && target->cpu_list) {61 target->cpu_list = NULL;62 if (ret == TARGET_ERRNO__SUCCESS)63 ret = TARGET_ERRNO__BPF_OVERRIDE_CPU;64 }65 66 /* BPF and PID/TID are mutually exclusive */67 if (target->bpf_str && target->tid) {68 target->tid = NULL;69 if (ret == TARGET_ERRNO__SUCCESS)70 ret = TARGET_ERRNO__BPF_OVERRIDE_PID;71 }72 73 /* BPF and UID are mutually exclusive */74 if (target->bpf_str && target->uid_str) {75 target->uid_str = NULL;76 if (ret == TARGET_ERRNO__SUCCESS)77 ret = TARGET_ERRNO__BPF_OVERRIDE_UID;78 }79 80 /* BPF and THREADS are mutually exclusive */81 if (target->bpf_str && target->per_thread) {82 target->per_thread = false;83 if (ret == TARGET_ERRNO__SUCCESS)84 ret = TARGET_ERRNO__BPF_OVERRIDE_THREAD;85 }86 87 /* THREAD and SYSTEM/CPU are mutually exclusive */88 if (target->per_thread && (target->system_wide || target->cpu_list)) {89 target->per_thread = false;90 if (ret == TARGET_ERRNO__SUCCESS)91 ret = TARGET_ERRNO__SYSTEM_OVERRIDE_THREAD;92 }93 94 return ret;95}96 97enum target_errno target__parse_uid(struct target *target)98{99 struct passwd pwd, *result;100 char buf[1024];101 const char *str = target->uid_str;102 103 target->uid = UINT_MAX;104 if (str == NULL)105 return TARGET_ERRNO__SUCCESS;106 107 /* Try user name first */108 getpwnam_r(str, &pwd, buf, sizeof(buf), &result);109 110 if (result == NULL) {111 /*112 * The user name not found. Maybe it's a UID number.113 */114 char *endptr;115 int uid = strtol(str, &endptr, 10);116 117 if (*endptr != '\0')118 return TARGET_ERRNO__INVALID_UID;119 120 getpwuid_r(uid, &pwd, buf, sizeof(buf), &result);121 122 if (result == NULL)123 return TARGET_ERRNO__USER_NOT_FOUND;124 }125 126 target->uid = result->pw_uid;127 return TARGET_ERRNO__SUCCESS;128}129 130/*131 * This must have a same ordering as the enum target_errno.132 */133static const char *target__error_str[] = {134 "PID/TID switch overriding CPU",135 "PID/TID switch overriding UID",136 "UID switch overriding CPU",137 "PID/TID switch overriding SYSTEM",138 "UID switch overriding SYSTEM",139 "SYSTEM/CPU switch overriding PER-THREAD",140 "BPF switch overriding CPU",141 "BPF switch overriding PID/TID",142 "BPF switch overriding UID",143 "BPF switch overriding THREAD",144 "Invalid User: %s",145 "Problems obtaining information for user %s",146};147 148int target__strerror(struct target *target, int errnum,149 char *buf, size_t buflen)150{151 int idx;152 const char *msg;153 154 BUG_ON(buflen == 0);155 156 if (errnum >= 0) {157 str_error_r(errnum, buf, buflen);158 return 0;159 }160 161 if (errnum < __TARGET_ERRNO__START || errnum >= __TARGET_ERRNO__END)162 return -1;163 164 idx = errnum - __TARGET_ERRNO__START;165 msg = target__error_str[idx];166 167 switch (errnum) {168 case TARGET_ERRNO__PID_OVERRIDE_CPU ...169 TARGET_ERRNO__BPF_OVERRIDE_THREAD:170 snprintf(buf, buflen, "%s", msg);171 break;172 173 case TARGET_ERRNO__INVALID_UID:174 case TARGET_ERRNO__USER_NOT_FOUND:175 snprintf(buf, buflen, msg, target->uid_str);176 break;177 178 default:179 /* cannot reach here */180 break;181 }182 183 return 0;184}185