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/dynamic-buffer.h>
  15 #include <common/buffer-view.h>
  16
  17 /*
  18  * No elf-specific comm structure is defined since no elf-specific payload is
  19  * currently needed.
  20  */
  21 struct lttng_userspace_probe_location_lookup_method_comm {
  22         /* enum lttng_userspace_probe_location_lookup_method_type */
  23         int8_t type;
  24         /* type-specific payload */
  25         char payload[];
  26 };
  27
  28 /* Common ancestor of all userspace probe location lookup methods. */
  29 struct lttng_userspace_probe_location_lookup_method {
  30         enum lttng_userspace_probe_location_lookup_method_type type;
  31 };
  32
  33 struct lttng_userspace_probe_location_lookup_method_elf {
  34         struct lttng_userspace_probe_location_lookup_method parent;
  35 };
  36
  37 struct lttng_userspace_probe_location_lookup_method_sdt {
  38         struct lttng_userspace_probe_location_lookup_method parent;
  39 };
  40
  41 struct lttng_userspace_probe_location_comm {
  42         /* enum lttng_userspace_probe_location_type */
  43         int8_t type;
  44         /*
  45          * Payload is composed of, in that order,
  46          *   - type-specific payload
  47          *   - struct lttng_userspace_probe_location_lookup_method_comm
  48          */
  49         char payload[];
  50 };
  51
  52 struct lttng_userspace_probe_location_function_comm {
  53         /* Both lengths include the trailing \0. */
  54         uint32_t function_name_len;
  55         uint32_t binary_path_len;
  56         /*
  57          * Payload is composed of, in that order,
  58          *   - function name (with trailing \0),
  59          *   - absolute binary path (with trailing \0)
  60          */
  61         char payload[];
  62 } LTTNG_PACKED;
  63
  64 struct lttng_userspace_probe_location_tracepoint_comm {
  65         /* The three lengths include the trailing \0. */
  66         uint32_t probe_name_len;
  67         uint32_t provider_name_len;
  68         uint32_t binary_path_len;
  69         /*
  70          * Payload is composed of, in that order,
  71          *   - probe name (with trailing \0),
  72          *   - provider name (with trailing \0),
  73          *   - absolute binary path (with trailing \0)
  74          */
  75         char payload[];
  76 } LTTNG_PACKED;
  77
  78 /* Common ancestor of all userspace probe locations. */
  79 struct lttng_userspace_probe_location {
  80         enum lttng_userspace_probe_location_type type;
  81         struct lttng_userspace_probe_location_lookup_method *lookup_method;
  82 };
  83
  84 struct lttng_userspace_probe_location_function {
  85         struct lttng_userspace_probe_location parent;
  86         char *function_name;
  87         char *binary_path;
  88         /*
  89          * binary_fd is a file descriptor to the executable file. It's open
  90          * early on to keep the backing inode valid over the course of the
  91          * intrumentation and use. It prevents deletion and reuse races.
  92          * Set to -1 if not open.
  93          */
  94         int binary_fd;
  95         enum lttng_userspace_probe_location_function_instrumentation_type instrumentation_type;
  96 };
  97
  98 struct lttng_userspace_probe_location_tracepoint {
  99         struct lttng_userspace_probe_location parent;
 100         char *probe_name;
 101         char *provider_name;
 102         char *binary_path;
 103         /*
 104          * binary_fd is a file descriptor to the executable file. It's open
 105          * early on to keep the backing inode valid over the course of the
 106          * intrumentation and use. It prevents deletion and reuse races.
 107          * Set to -1 if not open.
 108          */
 109         int binary_fd;
 110 };
 111
 112 LTTNG_HIDDEN
 113 int lttng_userspace_probe_location_serialize(
 114                 const struct lttng_userspace_probe_location *location,
 115                 struct lttng_dynamic_buffer *buffer,
 116                 int *binary_fd);
 117
 118 LTTNG_HIDDEN
 119 int lttng_userspace_probe_location_create_from_buffer(
 120                 const struct lttng_buffer_view *buffer,
 121                 struct lttng_userspace_probe_location **probe_location);
 122
 123 LTTNG_HIDDEN
 124 int lttng_userspace_probe_location_function_set_binary_fd(
 125                 struct lttng_userspace_probe_location *location, int binary_fd);
 126
 127 LTTNG_HIDDEN
 128 int lttng_userspace_probe_location_tracepoint_set_binary_fd(
 129                 struct lttng_userspace_probe_location *location, int binary_fd);
 130
 131 /*
 132  * Returns a version of the location that is serialized to a contiguous region
 133  * of memory. Pass NULL to buffer to only get the storage requirement of the
 134  * flattened userspace probe location.
 135  */
 136 LTTNG_HIDDEN
 137 int lttng_userspace_probe_location_flatten(
 138                 const struct lttng_userspace_probe_location *location,
 139                 struct lttng_dynamic_buffer *buffer);
 140
 141 LTTNG_HIDDEN
 142 struct lttng_userspace_probe_location *lttng_userspace_probe_location_copy(
 143                 const struct lttng_userspace_probe_location *location);
 144
 145 #endif /* LTTNG_USERSPACE_PROBE_INTERNAL_H */