include/lttng/userspace-probe-internal.h

   1 /*
   2  * Copyright (C) 2017 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   3  * Copyright (C) 2018 Francis Deslauriers <francis.deslauriers@efficios.com>
   4  *
   5  * SPDX-License-Identifier: LGPL-2.1-only
   6  *
   7  */
   8
   9 #ifndef LTTNG_USERSPACE_PROBE_INTERNAL_H
  10 #define LTTNG_USERSPACE_PROBE_INTERNAL_H
  11
  12 #include <lttng/userspace-probe.h>
  13 #include <common/macros.h>
  14 #include <common/fd-handle.h>
  15 #include <stdbool.h>
  16
  17 struct lttng_payload;
  18 struct lttng_payload_view;
  19 struct lttng_dynamic_buffer;
  20
  21 typedef bool (*userspace_probe_location_equal_cb)(
  22                 const struct lttng_userspace_probe_location *a,
  23                 const struct lttng_userspace_probe_location *b);
  24
  25 /*
  26  * No elf-specific comm structure is defined since no elf-specific payload is
  27  * currently needed.
  28  */
  29 struct lttng_userspace_probe_location_lookup_method_comm {
  30         /* enum lttng_userspace_probe_location_lookup_method_type */
  31         int8_t type;
  32         /* type-specific payload */
  33         char payload[];
  34 };
  35
  36 /* Common ancestor of all userspace probe location lookup methods. */
  37 struct lttng_userspace_probe_location_lookup_method {
  38         enum lttng_userspace_probe_location_lookup_method_type type;
  39 };
  40
  41 struct lttng_userspace_probe_location_lookup_method_elf {
  42         struct lttng_userspace_probe_location_lookup_method parent;
  43 };
  44
  45 struct lttng_userspace_probe_location_lookup_method_sdt {
  46         struct lttng_userspace_probe_location_lookup_method parent;
  47 };
  48
  49 struct lttng_userspace_probe_location_comm {
  50         /* enum lttng_userspace_probe_location_type */
  51         int8_t type;
  52         /*
  53          * Payload is composed of, in that order,
  54          *   - type-specific payload
  55          *   - struct lttng_userspace_probe_location_lookup_method_comm
  56          */
  57         char payload[];
  58 };
  59
  60 struct lttng_userspace_probe_location_function_comm {
  61         /* Both lengths include the trailing \0. */
  62         uint32_t function_name_len;
  63         uint32_t binary_path_len;
  64         /*
  65          * Payload is composed of, in that order,
  66          *   - function name (with trailing \0),
  67          *   - absolute binary path (with trailing \0)
  68          */
  69         char payload[];
  70 } LTTNG_PACKED;
  71
  72 struct lttng_userspace_probe_location_tracepoint_comm {
  73         /* The three lengths include the trailing \0. */
  74         uint32_t probe_name_len;
  75         uint32_t provider_name_len;
  76         uint32_t binary_path_len;
  77         /*
  78          * Payload is composed of, in that order,
  79          *   - probe name (with trailing \0),
  80          *   - provider name (with trailing \0),
  81          *   - absolute binary path (with trailing \0)
  82          */
  83         char payload[];
  84 } LTTNG_PACKED;
  85
  86 /* Common ancestor of all userspace probe locations. */
  87 struct lttng_userspace_probe_location {
  88         enum lttng_userspace_probe_location_type type;
  89         struct lttng_userspace_probe_location_lookup_method *lookup_method;
  90         userspace_probe_location_equal_cb equal;
  91 };
  92
  93 struct lttng_userspace_probe_location_function {
  94         struct lttng_userspace_probe_location parent;
  95         char *function_name;
  96         char *binary_path;
  97         /*
  98          * binary_fd is a file descriptor to the executable file. It's open
  99          * early on to keep the backing inode valid over the course of the
 100          * intrumentation and use. It prevents deletion and reuse races.
 101          */
 102         struct fd_handle *binary_fd_handle;
 103         enum lttng_userspace_probe_location_function_instrumentation_type instrumentation_type;
 104 };
 105
 106 struct lttng_userspace_probe_location_tracepoint {
 107         struct lttng_userspace_probe_location parent;
 108         char *probe_name;
 109         char *provider_name;
 110         char *binary_path;
 111         /*
 112          * binary_fd is a file descriptor to the executable file. It's open
 113          * early on to keep the backing inode valid over the course of the
 114          * intrumentation and use. It prevents deletion and reuse races.
 115          */
 116         struct fd_handle *binary_fd_handle;
 117 };
 118
 119 LTTNG_HIDDEN
 120 int lttng_userspace_probe_location_serialize(
 121                 const struct lttng_userspace_probe_location *location,
 122                 struct lttng_payload *payload);
 123
 124 LTTNG_HIDDEN
 125 int lttng_userspace_probe_location_create_from_payload(
 126                 struct lttng_payload_view *view,
 127                 struct lttng_userspace_probe_location **probe_location);
 128
 129 /*
 130  * Returns a version of the location that is serialized to a contiguous region
 131  * of memory. Pass NULL to buffer to only get the storage requirement of the
 132  * flattened userspace probe location.
 133  */
 134 LTTNG_HIDDEN
 135 int lttng_userspace_probe_location_flatten(
 136                 const struct lttng_userspace_probe_location *location,
 137                 struct lttng_dynamic_buffer *buffer);
 138
 139 LTTNG_HIDDEN
 140 struct lttng_userspace_probe_location *lttng_userspace_probe_location_copy(
 141                 const struct lttng_userspace_probe_location *location);
 142
 143 LTTNG_HIDDEN
 144 bool lttng_userspace_probe_location_lookup_method_is_equal(
 145                 const struct lttng_userspace_probe_location_lookup_method *a,
 146                 const struct lttng_userspace_probe_location_lookup_method *b);
 147
 148 LTTNG_HIDDEN
 149 bool lttng_userspace_probe_location_is_equal(
 150                 const struct lttng_userspace_probe_location *a,
 151                 const struct lttng_userspace_probe_location *b);
 152
 153 #endif /* LTTNG_USERSPACE_PROBE_INTERNAL_H */