X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=liblttng-ust%2Fcompat.h;h=e1f5f8b3f8ed5aeec2bd57f99df458ddf2bf0332;hb=7e80521b0585468a7ae9ad1cc1d862c8c7b3567e;hp=7d1ee590326fd1b9616569420b32846d4e458f7f;hpb=d9c56a93651a409c6ceea65ed1d7f33e3f5ee538;p=deliverable%2Flttng-ust.git

diff --git a/liblttng-ust/compat.h b/liblttng-ust/compat.h
index 7d1ee590..e1f5f8b3 100644
--- a/liblttng-ust/compat.h
+++ b/liblttng-ust/compat.h
@@ -4,6 +4,7 @@
 /*
  * 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>
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -21,11 +22,10 @@
  */
 
 #include <pthread.h>
+#include <errno.h>
+#include <string.h>
 
-/*
- * Limit imposed by Linux UST-sessiond ABI.
- */
-#define LTTNG_UST_PROCNAME_LEN 17
+#include <lttng/ust-abi.h>
 
 #define LTTNG_UST_PROCNAME_SUFFIX "-ust"
 
@@ -34,57 +34,99 @@
 static inline
 int lttng_pthread_setname_np(const char *name)
 {
-        return pthread_setname_np(pthread_self(), name);
+	/*
+	 * 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;
+	}
+
+	return pthread_setname_np(pthread_self(), name);
 }
 
 static inline
 int lttng_pthread_getname_np(char *name, size_t len)
 {
-        return pthread_getname_np(pthread_self(), name, 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);
+	return pthread_setname_np(name);
 }
 
 static inline
 int lttng_pthread_getname_np(char *name, size_t len)
 {
-        return pthread_getname_np(name, len);
+	return pthread_getname_np(name, len);
 }
-#else
-/*
- * For platforms without thread name support, do nothing.
- */
+#elif defined(HAVE_PTHREAD_SET_NAME_NP_WITH_TID)
+
+#include <pthread_np.h>
 static inline
 int lttng_pthread_setname_np(const char *name)
 {
-        return -ENOSYS;
+	/* Replicate pthread_setname_np's behavior */
+	if (strnlen(name, LTTNG_UST_ABI_PROCNAME_LEN) >= LTTNG_UST_ABI_PROCNAME_LEN) {
+		return ERANGE;
+	}
+
+	pthread_set_name_np(pthread_self(), name);
+	return 0;
 }
 
 static inline
 int lttng_pthread_getname_np(char *name, size_t len)
 {
-        return -ENOSYS;
+	pthread_get_name_np(pthread_self(), name, len);
+	return 0;
 }
-#endif
+#elif defined(__linux__)
+
+/* Fallback on prtctl on Linux */
+#include <sys/prctl.h>
 
 static inline
-void lttng_ust_getprocname(char *name)
+int lttng_pthread_setname_np(const char *name)
 {
-	lttng_pthread_getname_np(name, LTTNG_UST_PROCNAME_LEN);
+	/* 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
+
+/*
+ * 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
 int lttng_ust_setustprocname(void)
 {
 	int ret = 0, len;
-	char name[LTTNG_UST_PROCNAME_LEN];
-	int limit = LTTNG_UST_PROCNAME_LEN - strlen(LTTNG_UST_PROCNAME_SUFFIX) - 1;
-
-	lttng_pthread_getname_np(name, LTTNG_UST_PROCNAME_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) {
@@ -102,7 +144,6 @@ error:
 	return ret;
 }
 
-
 #include <errno.h>
 
 #ifndef ENODATA