LXR linux/tools/perf/util/target.c

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Helper functions for handling target threads/cpus
   4 *
   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        /* THREAD and SYSTEM/CPU are mutually exclusive */
  60        if (target->per_thread && (target->system_wide || target->cpu_list)) {
  61                target->per_thread = false;
  62                if (ret == TARGET_ERRNO__SUCCESS)
  63                        ret = TARGET_ERRNO__SYSTEM_OVERRIDE_THREAD;
  64        }
  65
  66        return ret;
  67}
  68
  69enum target_errno target__parse_uid(struct target *target)
  70{
  71        struct passwd pwd, *result;
  72        char buf[1024];
  73        const char *str = target->uid_str;
  74
  75        target->uid = UINT_MAX;
  76        if (str == NULL)
  77                return TARGET_ERRNO__SUCCESS;
  78
  79        /* Try user name first */
  80        getpwnam_r(str, &pwd, buf, sizeof(buf), &result);
  81
  82        if (result == NULL) {
  83                /*
  84                 * The user name not found. Maybe it's a UID number.
  85                 */
  86                char *endptr;
  87                int uid = strtol(str, &endptr, 10);
  88
  89                if (*endptr != '\0')
  90                        return TARGET_ERRNO__INVALID_UID;
  91
  92                getpwuid_r(uid, &pwd, buf, sizeof(buf), &result);
  93
  94                if (result == NULL)
  95                        return TARGET_ERRNO__USER_NOT_FOUND;
  96        }
  97
  98        target->uid = result->pw_uid;
  99        return TARGET_ERRNO__SUCCESS;
 100}
 101
 102/*
 103 * This must have a same ordering as the enum target_errno.
 104 */
 105static const char *target__error_str[] = {
 106        "PID/TID switch overriding CPU",
 107        "PID/TID switch overriding UID",
 108        "UID switch overriding CPU",
 109        "PID/TID switch overriding SYSTEM",
 110        "UID switch overriding SYSTEM",
 111        "SYSTEM/CPU switch overriding PER-THREAD",
 112        "Invalid User: %s",
 113        "Problems obtaining information for user %s",
 114};
 115
 116int target__strerror(struct target *target, int errnum,
 117                          char *buf, size_t buflen)
 118{
 119        int idx;
 120        const char *msg;
 121
 122        BUG_ON(buflen == 0);
 123
 124        if (errnum >= 0) {
 125                str_error_r(errnum, buf, buflen);
 126                return 0;
 127        }
 128
 129        if (errnum <  __TARGET_ERRNO__START || errnum >= __TARGET_ERRNO__END)
 130                return -1;
 131
 132        idx = errnum - __TARGET_ERRNO__START;
 133        msg = target__error_str[idx];
 134
 135        switch (errnum) {
 136        case TARGET_ERRNO__PID_OVERRIDE_CPU ...
 137             TARGET_ERRNO__SYSTEM_OVERRIDE_THREAD:
 138                snprintf(buf, buflen, "%s", msg);
 139                break;
 140
 141        case TARGET_ERRNO__INVALID_UID:
 142        case TARGET_ERRNO__USER_NOT_FOUND:
 143                snprintf(buf, buflen, msg, target->uid_str);
 144                break;
 145
 146        default:
 147                /* cannot reach here */
 148                break;
 149        }
 150
 151        return 0;
 152}
 153