struct lttng_ust_lib_ring_buffer_ctx *ctx,
const void *src, size_t len)
{
- struct channel_backend *chanb = &ctx->chan->backend;
- struct lttng_ust_shm_handle *handle = ctx->handle;
- size_t offset = ctx->buf_offset;
+ struct lttng_ust_lib_ring_buffer_ctx_private *ctx_private = ctx->priv;
+ struct channel_backend *chanb = &ctx_private->chan->backend;
+ struct lttng_ust_shm_handle *handle = ctx_private->chan->handle;
+ size_t offset = ctx_private->buf_offset;
struct lttng_ust_lib_ring_buffer_backend_pages *backend_pages;
void *p;
if (caa_unlikely(!p))
return;
lib_ring_buffer_do_copy(config, p, src, len);
- ctx->buf_offset += len;
+ ctx_private->buf_offset += len;
}
/*
struct lttng_ust_lib_ring_buffer_ctx *ctx,
const char *src, size_t len, char pad)
{
- struct channel_backend *chanb = &ctx->chan->backend;
- struct lttng_ust_shm_handle *handle = ctx->handle;
+ struct lttng_ust_lib_ring_buffer_ctx_private *ctx_private = ctx->priv;
+ struct channel_backend *chanb = &ctx_private->chan->backend;
+ struct lttng_ust_shm_handle *handle = ctx_private->chan->handle;
size_t count;
- size_t offset = ctx->buf_offset;
+ size_t offset = ctx_private->buf_offset;
struct lttng_ust_lib_ring_buffer_backend_pages *backend_pages;
void *p;
if (caa_unlikely(!p))
return;
lib_ring_buffer_do_memset(p, '\0', 1);
- ctx->buf_offset += len;
+ ctx_private->buf_offset += len;
+}
+
+/**
+ * lib_ring_buffer_pstrcpy - write to a buffer backend P-string
+ * @config : ring buffer instance configuration
+ * @ctx: ring buffer context. (input arguments only)
+ * @src : source pointer to copy from
+ * @len : length of data to copy
+ * @pad : character to use for padding
+ *
+ * This function copies up to @len bytes of data from a source pointer
+ * to a Pascal String into the buffer backend. If a terminating '\0'
+ * character is found in @src before @len characters are copied, pad the
+ * buffer with @pad characters (e.g. '\0').
+ *
+ * The length of the pascal strings in the ring buffer is explicit: it
+ * is either the array or sequence length.
+ */
+static inline __attribute__((always_inline))
+void lib_ring_buffer_pstrcpy(const struct lttng_ust_lib_ring_buffer_config *config,
+ struct lttng_ust_lib_ring_buffer_ctx *ctx,
+ const char *src, size_t len, char pad)
+{
+ struct lttng_ust_lib_ring_buffer_ctx_private *ctx_private = ctx->priv;
+ struct channel_backend *chanb = &ctx_private->chan->backend;
+ struct lttng_ust_shm_handle *handle = ctx_private->chan->handle;
+ size_t count;
+ size_t offset = ctx_private->buf_offset;
+ struct lttng_ust_lib_ring_buffer_backend_pages *backend_pages;
+ void *p;
+
+ if (caa_unlikely(!len))
+ return;
+ /*
+ * Underlying layer should never ask for writes across
+ * subbuffers.
+ */
+ CHAN_WARN_ON(chanb, (offset & (chanb->buf_size - 1)) + len > chanb->buf_size);
+ backend_pages = lib_ring_buffer_get_backend_pages_from_ctx(config, ctx);
+ if (caa_unlikely(!backend_pages)) {
+ if (lib_ring_buffer_backend_get_pages(config, ctx, &backend_pages))
+ return;
+ }
+ p = shmp_index(handle, backend_pages->p, offset & (chanb->subbuf_size - 1));
+ if (caa_unlikely(!p))
+ return;
+
+ count = lib_ring_buffer_do_strcpy(config, p, src, len);
+ offset += count;
+ /* Padding */
+ if (caa_unlikely(count < len)) {
+ size_t pad_len = len - count;
+
+ p = shmp_index(handle, backend_pages->p, offset & (chanb->subbuf_size - 1));
+ if (caa_unlikely(!p))
+ return;
+ lib_ring_buffer_do_memset(p, pad, pad_len);
+ }
+ ctx_private->buf_offset += len;
}
/*