Move to kernel style SPDX license identifiers

[lttng-ust.git] / liblttng-ust / compat.h

diff --git a/liblttng-ust/compat.h b/liblttng-ust/compat.h
index 05b85a930615516da7175af84661ce144f7d5127..200d9771f85462b91ceabb7b5404254787e25fb9 100644 (file)
--- a/liblttng-ust/compat.h
+++ b/liblttng-ust/compat.h
@@ -1,80 +1,141 @@
-#ifndef _UST_COMPAT_H
-#define _UST_COMPAT_H
-
 /*
- * Copyright (C) 2011   Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- *
- * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
- * OR IMPLIED.  ANY USE IS AT YOUR OWN RISK.
+ * SPDX-License-Identifier: LGPL-2.1-only
  *
- * Permission is hereby granted to use or copy this program
- * for any purpose,  provided the above notices are retained on all copies.
- * Permission to modify the code and to distribute modified code is granted,
- * provided the above notices are retained, and a notice that the code was
- * modified is included with the above copyright notice.
+ * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ * Copyright (C) 2016 Raphaël Beamonte <raphael.beamonte@gmail.com>
+ * Copyright (C) 2020 Michael Jeanson <mjeanson@efficios.com>
  */
 
-/*
- * sched_getcpu.
- */
-#ifdef __linux__
+#ifndef _UST_COMPAT_H
+#define _UST_COMPAT_H
+
+#include <pthread.h>
+#include <errno.h>
+#include <string.h>
+
+#include <lttng/ust-abi.h>
+
+#define LTTNG_UST_PROCNAME_SUFFIX "-ust"
+
 
-#ifdef __UCLIBC__
-#include <sys/syscall.h>
-#define __getcpu(cpu, node, cache)     syscall(__NR_getcpu, cpu, node, cache)
+#if defined(HAVE_PTHREAD_SETNAME_NP_WITH_TID)
 static inline
-int sched_getcpu(void)
+int lttng_pthread_setname_np(const char *name)
 {
-       int c, s;
+       /*
+        * Some implementations don't error out, replicate this behavior for
+        * consistency.
+        */
+       if (strnlen(name, LTTNG_UST_ABI_PROCNAME_LEN) >= LTTNG_UST_ABI_PROCNAME_LEN) {
+               return ERANGE;
+       }
 
-       s = __getcpu(&c, NULL, NULL);
-       return (s == -1) ? s : c;
+       return pthread_setname_np(pthread_self(), name);
 }
-#endif /* __UCLIBC__ */
 
-#else
-#error "Please add support for your OS into liblttng-ust/compat.h."
-#endif
+static inline
+int lttng_pthread_getname_np(char *name, size_t len)
+{
+       return pthread_getname_np(pthread_self(), name, len);
+}
+#elif defined(HAVE_PTHREAD_SETNAME_NP_WITHOUT_TID)
+static inline
+int lttng_pthread_setname_np(const char *name)
+{
+       return pthread_setname_np(name);
+}
 
-/*
- * lttng_ust_getprocname.
- */
-#ifdef __linux__
+static inline
+int lttng_pthread_getname_np(char *name, size_t len)
+{
+       return pthread_getname_np(name, len);
+}
+#elif defined(HAVE_PTHREAD_SET_NAME_NP_WITH_TID)
 
-#include <sys/prctl.h>
+#include <pthread_np.h>
+static inline
+int lttng_pthread_setname_np(const char *name)
+{
+       /* Replicate pthread_setname_np's behavior */
+       if (strnlen(name, LTTNG_UST_ABI_PROCNAME_LEN) >= LTTNG_UST_ABI_PROCNAME_LEN) {
+               return ERANGE;
+       }
 
-#define LTTNG_UST_PROCNAME_LEN 17
+       pthread_set_name_np(pthread_self(), name);
+       return 0;
+}
 
 static inline
-void lttng_ust_getprocname(char *name)
+int lttng_pthread_getname_np(char *name, size_t len)
 {
-       (void) prctl(PR_GET_NAME, (unsigned long) name, 0, 0, 0);
+       pthread_get_name_np(pthread_self(), name, len);
+       return 0;
 }
+#elif defined(__linux__)
 
-#elif defined(__FreeBSD__)
-#include <stdlib.h>
-#include <string.h>
+/* Fallback on prtctl on Linux */
+#include <sys/prctl.h>
 
-/*
- * Limit imposed by Linux UST-sessiond ABI.
- */
-#define LTTNG_UST_PROCNAME_LEN 17
+static inline
+int lttng_pthread_setname_np(const char *name)
+{
+       /* Replicate pthread_setname_np's behavior */
+       if (strnlen(name, LTTNG_UST_ABI_PROCNAME_LEN) >= LTTNG_UST_ABI_PROCNAME_LEN) {
+               return ERANGE;
+       }
+       return prctl(PR_SET_NAME, name, 0, 0, 0);
+}
+
+static inline
+int lttng_pthread_getname_np(char *name, size_t len)
+{
+       return prctl(PR_GET_NAME, name, 0, 0, 0);
+}
+
+#else
+#error "Please add pthread name support for your OS."
+#endif
 
 /*
- * Acts like linux prctl, the string is not necessarily 0-terminated if
- * 16-byte long.
+ * If a pthread setname/set_name function is available, declare
+ * the setustprocname() function that will add '-ust' to the end
+ * of the current process name, while truncating it if needed.
  */
 static inline
-void lttng_ust_getprocname(char *name)
+int lttng_ust_setustprocname(void)
 {
-       const char *bsd_name;
+       int ret = 0, len;
+       char name[LTTNG_UST_ABI_PROCNAME_LEN];
+       int limit = LTTNG_UST_ABI_PROCNAME_LEN - strlen(LTTNG_UST_PROCNAME_SUFFIX) - 1;
+
+       /*
+        * Get the current thread name.
+        */
+       ret = lttng_pthread_getname_np(name, LTTNG_UST_ABI_PROCNAME_LEN);
+       if (ret) {
+               goto error;
+       }
+
+       len = strlen(name);
+       if (len > limit) {
+               len = limit;
+       }
 
-       bsd_name = getprogname();
-       if (!bsd_name)
-               name[0] = '\0';
-       memcpy(name, bsd_name, LTTNG_UST_PROCNAME_LEN - 1);
+       ret = sprintf(name + len, LTTNG_UST_PROCNAME_SUFFIX);
+       if (ret != strlen(LTTNG_UST_PROCNAME_SUFFIX)) {
+               goto error;
+       }
+
+       ret = lttng_pthread_setname_np(name);
+
+error:
+       return ret;
 }
 
+#include <errno.h>
+
+#ifndef ENODATA
+#define ENODATA        ENOMSG
 #endif
 
 #endif /* _UST_COMPAT_H */