liblttng-ust/compat.h

   1 #ifndef _UST_COMPAT_H
   2 #define _UST_COMPAT_H
   3
   4 /*
   5  * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   6  * Copyright (C) 2016 Raphaël Beamonte <raphael.beamonte@gmail.com>
   7  * Copyright (C) 2020 Michael Jeanson <mjeanson@efficios.com>
   8  *
   9  * This library is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public
  11  * License as published by the Free Software Foundation; only
  12  * version 2.1 of the License.
  13  *
  14  * This library is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  17  * Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public
  20  * License along with this library; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  22  */
  23
  24 #include <pthread.h>
  25 #include <errno.h>
  26 #include <string.h>
  27
  28 #include <lttng/ust-abi.h>
  29
  30 #define LTTNG_UST_PROCNAME_SUFFIX "-ust"
  31
  32
  33 #if defined(HAVE_PTHREAD_SETNAME_NP_WITH_TID)
  34 static inline
  35 int lttng_pthread_setname_np(const char *name)
  36 {
  37         /*
  38          * Some implementations don't error out, replicate this behavior for
  39          * consistency.
  40          */
  41         if (strnlen(name, LTTNG_UST_ABI_PROCNAME_LEN) >= LTTNG_UST_ABI_PROCNAME_LEN) {
  42                 return ERANGE;
  43         }
  44
  45         return pthread_setname_np(pthread_self(), name);
  46 }
  47
  48 static inline
  49 int lttng_pthread_getname_np(char *name, size_t len)
  50 {
  51         return pthread_getname_np(pthread_self(), name, len);
  52 }
  53 #elif defined(HAVE_PTHREAD_SETNAME_NP_WITHOUT_TID)
  54 static inline
  55 int lttng_pthread_setname_np(const char *name)
  56 {
  57         return pthread_setname_np(name);
  58 }
  59
  60 static inline
  61 int lttng_pthread_getname_np(char *name, size_t len)
  62 {
  63         return pthread_getname_np(name, len);
  64 }
  65 #elif defined(HAVE_PTHREAD_SET_NAME_NP_WITH_TID)
  66
  67 #include <pthread_np.h>
  68 static inline
  69 int lttng_pthread_setname_np(const char *name)
  70 {
  71         /* Replicate pthread_setname_np's behavior */
  72         if (strnlen(name, LTTNG_UST_ABI_PROCNAME_LEN) >= LTTNG_UST_ABI_PROCNAME_LEN) {
  73                 return ERANGE;
  74         }
  75
  76         pthread_set_name_np(pthread_self(), name);
  77         return 0;
  78 }
  79
  80 static inline
  81 int lttng_pthread_getname_np(char *name, size_t len)
  82 {
  83         pthread_get_name_np(pthread_self(), name, len);
  84         return 0;
  85 }
  86 #elif defined(__linux__)
  87
  88 /* Fallback on prtctl on Linux */
  89 #include <sys/prctl.h>
  90
  91 static inline
  92 int lttng_pthread_setname_np(const char *name)
  93 {
  94         /* Replicate pthread_setname_np's behavior */
  95         if (strnlen(name, LTTNG_UST_ABI_PROCNAME_LEN) >= LTTNG_UST_ABI_PROCNAME_LEN) {
  96                 return ERANGE;
  97         }
  98         return prctl(PR_SET_NAME, name, 0, 0, 0);
  99 }
 100
 101 static inline
 102 int lttng_pthread_getname_np(char *name, size_t len)
 103 {
 104         return prctl(PR_GET_NAME, name, 0, 0, 0);
 105 }
 106
 107 #else
 108 #error "Please add pthread name support for your OS."
 109 #endif
 110
 111 /*
 112  * If a pthread setname/set_name function is available, declare
 113  * the setustprocname() function that will add '-ust' to the end
 114  * of the current process name, while truncating it if needed.
 115  */
 116 static inline
 117 int lttng_ust_setustprocname(void)
 118 {
 119         int ret = 0, len;
 120         char name[LTTNG_UST_ABI_PROCNAME_LEN];
 121         int limit = LTTNG_UST_ABI_PROCNAME_LEN - strlen(LTTNG_UST_PROCNAME_SUFFIX) - 1;
 122
 123         /*
 124          * Get the current thread name.
 125          */
 126         ret = lttng_pthread_getname_np(name, LTTNG_UST_ABI_PROCNAME_LEN);
 127         if (ret) {
 128                 goto error;
 129         }
 130
 131         len = strlen(name);
 132         if (len > limit) {
 133                 len = limit;
 134         }
 135
 136         ret = sprintf(name + len, LTTNG_UST_PROCNAME_SUFFIX);
 137         if (ret != strlen(LTTNG_UST_PROCNAME_SUFFIX)) {
 138                 goto error;
 139         }
 140
 141         ret = lttng_pthread_setname_np(name);
 142
 143 error:
 144         return ret;
 145 }
 146
 147 #include <errno.h>
 148
 149 #ifndef ENODATA
 150 #define ENODATA ENOMSG
 151 #endif
 152
 153 #endif /* _UST_COMPAT_H */