nbdkit/0004-server-Introduce-threadlocal_-set-get-_last_error.patch

94 lines
3.0 KiB
Diff
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

From fa5055ae2b9f96af941d697de39198c96ee2580a Mon Sep 17 00:00:00 2001
From: "Richard W.M. Jones" <rjones@redhat.com>
Date: Wed, 24 Jul 2024 10:37:58 +0100
Subject: [PATCH] server: Introduce threadlocal_{set,get}_last_error
Plus a function to clear the last_error field.
---
server/internal.h | 3 +++
server/threadlocal.c | 40 ++++++++++++++++++++++++++++++++++++++++
2 files changed, 43 insertions(+)
diff --git a/server/internal.h b/server/internal.h
index 8102ccde..c45384a6 100644
--- a/server/internal.h
+++ b/server/internal.h
@@ -571,6 +571,9 @@ extern void threadlocal_set_instance_num (size_t instance_num);
extern size_t threadlocal_get_instance_num (void);
extern void threadlocal_set_errno (int err);
extern int threadlocal_get_errno (void);
+extern void threadlocal_set_last_error (char *msg);
+extern void threadlocal_clear_last_error (void);
+extern const char *threadlocal_get_last_error (void);
extern void *threadlocal_buffer (size_t size);
extern void threadlocal_set_conn (struct connection *conn);
extern struct connection *threadlocal_get_conn (void);
diff --git a/server/threadlocal.c b/server/threadlocal.c
index 9bb656bc..74a3c4e5 100644
--- a/server/threadlocal.c
+++ b/server/threadlocal.c
@@ -56,6 +56,7 @@ struct threadlocal {
char *name; /* Can be NULL. */
size_t instance_num; /* Can be 0. */
int err;
+ char *last_error; /* Can be NULL. */
void *buffer; /* Can be NULL. */
size_t buffer_size;
struct connection *conn; /* Can be NULL. */
@@ -70,6 +71,7 @@ free_threadlocal (void *threadlocalv)
struct threadlocal *threadlocal = threadlocalv;
free (threadlocal->name);
+ free (threadlocal->last_error);
free (threadlocal->buffer);
free (threadlocal);
}
@@ -176,6 +178,44 @@ threadlocal_get_errno (void)
return threadlocal ? threadlocal->err : 0;
}
+/* Set the last_error field. The ownership of the 'msg' string is
+ * passed to the threadlocal and will be freed here.
+ */
+void
+threadlocal_set_last_error (char *msg)
+{
+ struct threadlocal *threadlocal = pthread_getspecific (threadlocal_key);
+
+ if (threadlocal) {
+ free (threadlocal->last_error);
+ threadlocal->last_error = msg;
+ }
+ else {
+ /* ... otherwise throw it away, it's informational. */
+ free (msg);
+ }
+}
+
+void
+threadlocal_clear_last_error (void)
+{
+ threadlocal_set_last_error (NULL);
+}
+
+/* Get the last_error field. If successful, this returns a non-NULL
+ * string. This is valid until something calls nbdkit_error() in the
+ * same thread, so it should be used quickly. Returning NULL is not
+ * necessarily an error. The last_error is informational and may not
+ * be available.
+ */
+const char *
+threadlocal_get_last_error (void)
+{
+ struct threadlocal *threadlocal = pthread_getspecific (threadlocal_key);
+
+ return threadlocal ? threadlocal->last_error : NULL;
+}
+
/* Return the single pread/pwrite buffer for this thread. The buffer
* size is increased to size bytes if required.
*
--
2.43.0