tools/perf/util/target.c

   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                         size_t len = strlen(err);
 128                         memcpy(buf, err, min(buflen - 1, len));
 129                         *(buf + min(buflen - 1, len)) = '\0';
 130                 }
 131
 132                 return 0;
 133         }
 134
 135         if (errnum <  __TARGET_ERRNO__START || errnum >= __TARGET_ERRNO__END)
 136                 return -1;
 137
 138         idx = errnum - __TARGET_ERRNO__START;
 139         msg = target__error_str[idx];
 140
 141         switch (errnum) {
 142         case TARGET_ERRNO__PID_OVERRIDE_CPU ...
 143              TARGET_ERRNO__SYSTEM_OVERRIDE_THREAD:
 144                 snprintf(buf, buflen, "%s", msg);
 145                 break;
 146
 147         case TARGET_ERRNO__INVALID_UID:
 148         case TARGET_ERRNO__USER_NOT_FOUND:
 149                 snprintf(buf, buflen, msg, target->uid_str);
 150                 break;
 151
 152         default:
 153                 /* cannot reach here */
 154                 break;
 155         }
 156
 157         return 0;
 158 }