src/common/payload-view.c

   1 /*
   2  * Copyright (C) 2020 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   3  *
   4  * SPDX-License-Identifier: LGPL-2.1-only
   5  *
   6  */
   7
   8 #include <common/dynamic-array.h>
   9 #include <common/buffer-view.h>
  10 #include "payload-view.h"
  11 #include "payload.h"
  12 #include <stddef.h>
  13
  14 bool lttng_payload_view_is_valid(const struct lttng_payload_view *view)
  15 {
  16         return view && lttng_buffer_view_is_valid(&view->buffer);
  17 }
  18
  19 struct lttng_payload_view lttng_payload_view_from_payload(
  20                 const struct lttng_payload *payload, size_t offset,
  21                 ptrdiff_t len)
  22 {
  23         return payload ? (struct lttng_payload_view) {
  24                 .buffer = lttng_buffer_view_from_dynamic_buffer(
  25                         &payload->buffer, offset, len),
  26                 ._fd_handles = payload->_fd_handles,
  27                 } : (struct lttng_payload_view) {};
  28 }
  29
  30 struct lttng_payload_view lttng_payload_view_from_view(
  31                 struct lttng_payload_view *view, size_t offset,
  32                 ptrdiff_t len)
  33 {
  34         return view ? (struct lttng_payload_view) {
  35                 .buffer = lttng_buffer_view_from_view(
  36                                 &view->buffer, offset, len),
  37                 ._fd_handles = view->_fd_handles,
  38                 ._iterator.p_fd_handles_position = view->_iterator.p_fd_handles_position ?:
  39                                 &view->_iterator.fd_handles_position,
  40                 } : (struct lttng_payload_view) {};
  41 }
  42
  43 struct lttng_payload_view lttng_payload_view_from_dynamic_buffer(
  44                 const struct lttng_dynamic_buffer *buffer, size_t offset,
  45                 ptrdiff_t len)
  46 {
  47         return buffer ? (struct lttng_payload_view) {
  48                 .buffer = lttng_buffer_view_from_dynamic_buffer(
  49                         buffer, offset, len)
  50                 } : (struct lttng_payload_view) {};
  51 }
  52
  53 struct lttng_payload_view lttng_payload_view_from_buffer_view(
  54                 const struct lttng_buffer_view *view, size_t offset,
  55                 ptrdiff_t len)
  56 {
  57         return view ? (struct lttng_payload_view) {
  58                 .buffer = lttng_buffer_view_from_view(
  59                         view, offset, len)
  60                 } : (struct lttng_payload_view) {};
  61 }
  62
  63 struct lttng_payload_view lttng_payload_view_init_from_buffer(
  64         const char *src, size_t offset, ptrdiff_t len)
  65 {
  66         return (struct lttng_payload_view) {
  67                 .buffer = lttng_buffer_view_init(
  68                         src, offset, len)
  69         };
  70 }
  71
  72 int lttng_payload_view_get_fd_handle_count(
  73                 const struct lttng_payload_view *payload_view)
  74 {
  75         int ret;
  76         size_t position;
  77
  78         if (!payload_view) {
  79                 ret = -1;
  80                 goto end;
  81         }
  82
  83         ret = lttng_dynamic_pointer_array_get_count(&payload_view->_fd_handles);
  84         if (ret < 0) {
  85                 goto end;
  86         }
  87
  88         position = payload_view->_iterator.p_fd_handles_position ?
  89                         *payload_view->_iterator.p_fd_handles_position :
  90                         payload_view->_iterator.fd_handles_position;
  91         ret = ret - (int) position;
  92 end:
  93         return ret;
  94 }
  95
  96 struct fd_handle *lttng_payload_view_pop_fd_handle(
  97                 struct lttng_payload_view *view)
  98 {
  99         struct fd_handle *handle = NULL;
 100         size_t fd_handle_count;
 101         size_t *pos;
 102
 103         if (!view) {
 104                 goto end;
 105         }
 106
 107         fd_handle_count = lttng_payload_view_get_fd_handle_count(view);
 108         if (fd_handle_count == 0) {
 109                 goto end;
 110         }
 111
 112         pos = view->_iterator.p_fd_handles_position ?
 113                         view->_iterator.p_fd_handles_position :
 114                         &view->_iterator.fd_handles_position;
 115         handle = lttng_dynamic_pointer_array_get_pointer(&view->_fd_handles,
 116                         *pos);
 117         (*pos)++;
 118         fd_handle_get(handle);
 119 end:
 120         return handle;
 121 }