[PATCH RFC] add pthread_setname_np

[Felix Janda <felix.janda@posteo.de>]

gdb's "info threads" displays the thread name.
---
Should this function care about interrupted syscalls?
---
 include/pthread.h               |  1 +
 src/thread/pthread_setname_np.c | 21 +++++++++++++++++++++
 2 files changed, 22 insertions(+)
 create mode 100644 src/thread/pthread_setname_np.c

diff --git a/include/pthread.h b/include/pthread.h
index 3d2e0c4..94ef919 100644
--- a/include/pthread.h
+++ b/include/pthread.h
@@ -214,6 +214,7 @@ struct cpu_set_t;
 int pthread_getaffinity_np(pthread_t, size_t, struct cpu_set_t *);
 int pthread_setaffinity_np(pthread_t, size_t, const struct cpu_set_t *);
 int pthread_getattr_np(pthread_t, pthread_attr_t *);
+int pthread_setname_np(pthread_t, const char *);
 int pthread_tryjoin_np(pthread_t, void **);
 int pthread_timedjoin_np(pthread_t, void **, const struct timespec *);
 #endif
diff --git a/src/thread/pthread_setname_np.c b/src/thread/pthread_setname_np.c
new file mode 100644
index 0000000..b7f7a4b
--- /dev/null
+++ b/src/thread/pthread_setname_np.c
@@ -0,0 +1,21 @@
+#include <fcntl.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "pthread_impl.h"
+
+int pthread_setname_np(pthread_t thread, const char *name)
+{
+	int fd, status = 0;
+	char f[sizeof "/proc/self/task//comm" + 7];
+	ssize_t len;
+
+	if ((len = strlen(name)) > 15) return ERANGE;
+
+	snprintf(f, sizeof f, "/proc/self/task/%d/comm", thread->tid);
+	if ((fd = open(f, O_WRONLY)) < 0) return errno;
+	if (write(fd, name, len) < 0) status = errno;
+
+	close(fd);
+	return status;
+}
-- 
2.7.3