uprobe: transmit binary file descritptor through lttng_payload

[lttng-tools.git] / src / common / payload.c

diff --git a/src/common/payload.c b/src/common/payload.c
index 592964a519b13ce6996e178df222b50e3cd81e5a..635d3e3fbc65bdda94386ec1111ca92e45d01fb5 100644 (file)
--- a/src/common/payload.c
+++ b/src/common/payload.c
@@ -6,6 +6,9 @@
  */
 
 #include "payload.h"
+#include <common/dynamic-array.h>
+#include <common/dynamic-buffer.h>
+#include <common/error.h>
 
 LTTNG_HIDDEN
 void lttng_payload_init(struct lttng_payload *payload)
@@ -15,6 +18,52 @@ void lttng_payload_init(struct lttng_payload *payload)
        lttng_dynamic_array_init(&payload->_fds, sizeof(int), NULL);
 }
 
+LTTNG_HIDDEN
+int lttng_payload_copy(const struct lttng_payload *src_payload,
+                      struct lttng_payload *dst_payload)
+{
+       int ret;
+       size_t i;
+
+       lttng_payload_init(dst_payload);
+       ret = lttng_dynamic_buffer_append_buffer(
+                       &dst_payload->buffer, &src_payload->buffer);
+       if (ret) {
+               goto error;
+       }
+
+       for (i = 0; i < lttng_dynamic_array_get_count(&src_payload->_fds);
+                       i++) {
+               int dst_fd;
+               const int src_fd = *((int *) lttng_dynamic_array_get_element(
+                                            &src_payload->_fds, i));
+
+               dst_fd = dup(src_fd);
+               if (dst_fd < 0) {
+                       PERROR("Failed to duplicate file descriptor while copying a payload");
+                       ret = dst_fd;
+                       goto error;
+               }
+
+               ret = lttng_payload_push_fd(dst_payload, dst_fd);
+               if (ret) {
+                       const int close_ret = close(dst_fd);
+
+                       if (close_ret < 0) {
+                               PERROR("Failed to close duplicated file descriptor while copying a payload");
+                       }
+
+                       goto error;
+               }
+       }
+
+end:
+       return ret;
+error:
+       lttng_payload_reset(dst_payload);
+       goto end;
+}
+
 LTTNG_HIDDEN
 void lttng_payload_reset(struct lttng_payload *payload)
 {