liblttng-ust/compat.h

   1 /*
   2  * SPDX-License-Identifier: LGPL-2.1-only
   3  *
   4  * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   5  * Copyright (C) 2016 Raphaël Beamonte <raphael.beamonte@gmail.com>
   6  * Copyright (C) 2020 Michael Jeanson <mjeanson@efficios.com>
   7  */
   8
   9 #ifndef _UST_COMPAT_H
  10 #define _UST_COMPAT_H
  11
  12 #include <pthread.h>
  13 #include <errno.h>
  14 #include <string.h>
  15
  16 #ifdef __FreeBSD__
  17 #include <pthread_np.h>
  18 #endif
  19
  20 #include <lttng/ust-abi.h>
  21
  22 #define LTTNG_UST_PROCNAME_SUFFIX "-ust"
  23
  24
  25 #if defined(HAVE_PTHREAD_SETNAME_NP_WITH_TID)
  26 static inline
  27 int lttng_pthread_setname_np(const char *name)
  28 {
  29         /*
  30          * Some implementations don't error out, replicate this behavior for
  31          * consistency.
  32          */
  33         if (strnlen(name, LTTNG_UST_ABI_PROCNAME_LEN) >= LTTNG_UST_ABI_PROCNAME_LEN) {
  34                 return ERANGE;
  35         }
  36
  37         return pthread_setname_np(pthread_self(), name);
  38 }
  39 #elif defined(HAVE_PTHREAD_SETNAME_NP_WITHOUT_TID)
  40 static inline
  41 int lttng_pthread_setname_np(const char *name)
  42 {
  43         return pthread_setname_np(name);
  44 }
  45 #elif defined(HAVE_PTHREAD_SET_NAME_NP_WITH_TID)
  46
  47 static inline
  48 int lttng_pthread_setname_np(const char *name)
  49 {
  50         /* Replicate pthread_setname_np's behavior */
  51         if (strnlen(name, LTTNG_UST_ABI_PROCNAME_LEN) >= LTTNG_UST_ABI_PROCNAME_LEN) {
  52                 return ERANGE;
  53         }
  54
  55         pthread_set_name_np(pthread_self(), name);
  56         return 0;
  57 }
  58 #elif defined(__linux__)
  59
  60 /* Fallback on prtctl on Linux */
  61 #include <sys/prctl.h>
  62
  63 static inline
  64 int lttng_pthread_setname_np(const char *name)
  65 {
  66         /* Replicate pthread_setname_np's behavior */
  67         if (strnlen(name, LTTNG_UST_ABI_PROCNAME_LEN) >= LTTNG_UST_ABI_PROCNAME_LEN) {
  68                 return ERANGE;
  69         }
  70         return prctl(PR_SET_NAME, name, 0, 0, 0);
  71 }
  72 #else
  73 #error "Please add pthread set name support for your OS."
  74 #endif
  75
  76
  77 #if defined(HAVE_PTHREAD_GETNAME_NP_WITH_TID)
  78 static inline
  79 int lttng_pthread_getname_np(char *name, size_t len)
  80 {
  81         return pthread_getname_np(pthread_self(), name, len);
  82 }
  83 #elif defined(HAVE_PTHREAD_GETNAME_NP_WITHOUT_TID)
  84 static inline
  85 int lttng_pthread_getname_np(char *name, size_t len)
  86 {
  87         return pthread_getname_np(name, len);
  88 }
  89 #elif defined(HAVE_PTHREAD_GET_NAME_NP_WITH_TID)
  90
  91 static inline
  92 int lttng_pthread_getname_np(char *name, size_t len)
  93 {
  94         pthread_get_name_np(pthread_self(), name, len);
  95         return 0;
  96 }
  97 #elif defined(__linux__)
  98
  99 /* Fallback on prtctl on Linux */
 100 #include <sys/prctl.h>
 101
 102 static inline
 103 int lttng_pthread_getname_np(char *name, size_t len)
 104 {
 105         return prctl(PR_GET_NAME, name, 0, 0, 0);
 106 }
 107
 108 #else
 109 #error "Please add pthread get name support for your OS."
 110 #endif
 111
 112 /*
 113  * If a pthread setname/set_name function is available, declare
 114  * the setustprocname() function that will add '-ust' to the end
 115  * of the current process name, while truncating it if needed.
 116  */
 117 static inline
 118 int lttng_ust_setustprocname(void)
 119 {
 120         int ret = 0, len;
 121         char name[LTTNG_UST_ABI_PROCNAME_LEN];
 122         int limit = LTTNG_UST_ABI_PROCNAME_LEN - strlen(LTTNG_UST_PROCNAME_SUFFIX) - 1;
 123
 124         /*
 125          * Get the current thread name.
 126          */
 127         ret = lttng_pthread_getname_np(name, LTTNG_UST_ABI_PROCNAME_LEN);
 128         if (ret) {
 129                 goto error;
 130         }
 131
 132         len = strlen(name);
 133         if (len > limit) {
 134                 len = limit;
 135         }
 136
 137         ret = sprintf(name + len, LTTNG_UST_PROCNAME_SUFFIX);
 138         if (ret != strlen(LTTNG_UST_PROCNAME_SUFFIX)) {
 139                 goto error;
 140         }
 141
 142         ret = lttng_pthread_setname_np(name);
 143
 144 error:
 145         return ret;
 146 }
 147
 148 #include <errno.h>
 149
 150 #ifndef ENODATA
 151 #define ENODATA ENOMSG
 152 #endif
 153
 154 #endif /* _UST_COMPAT_H */