drgn/docs/api_reference.rst
Omar Sandoval 6c7b65fde6 Add stack_trace() shortcut function
A few people have told me that they frequently forget whether
stack_trace() is a Program method or a function. Now that we have a
default program, it can be both.

Signed-off-by: Omar Sandoval <osandov@osandov.com>
2023-11-30 14:44:51 -08:00

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API Reference
=============
.. module:: drgn
Programs
--------
.. drgndoc:: Program
:exclude: (void|int|bool|float|struct|union|class|enum|typedef|pointer|array|function)_type
.. drgndoc:: ProgramFlags
.. drgndoc:: FindObjectFlags
.. drgndoc:: Thread
.. _api-filenames:
Filenames
^^^^^^^^^
The :meth:`Program.type()`, :meth:`Program.object()`,
:meth:`Program.variable()`, :meth:`Program.constant()`, and
:meth:`Program.function()` methods all take a *filename* parameter to
distinguish between multiple definitions with the same name. The filename
refers to the source code file that contains the definition. It is matched with
:func:`filename_matches()`. If multiple definitions match, one is returned
arbitrarily.
.. drgndoc:: filename_matches
.. _api-program-constructors:
Program Constructors
^^^^^^^^^^^^^^^^^^^^
The drgn command line interface automatically creates a :class:`Program` named
``prog``. However, drgn may also be used as a library without the CLI, in which
case a ``Program`` must be created manually.
.. drgndoc:: program_from_core_dump
.. drgndoc:: program_from_kernel
.. drgndoc:: program_from_pid
.. _default-program:
Default Program
^^^^^^^^^^^^^^^
Most functions that take a :class:`Program` can be called without the *prog*
argument. In that case, the *default program argument* is used, which is
determined by the rules below.
.. note::
In the drgn CLI, you probably don't need to care about these details.
Simply omit *prog*:
.. code-block:: python3
# Equivalent in the CLI.
find_task(pid)
find_task(prog, pid)
find_task(prog["init_pid_ns"].address_of_(), pid)
1. If *prog* is given explicitly, either as a positional or keyword argument,
then it is used.
2. Otherwise, if the first argument is an :class:`Object`, then
:attr:`Object.prog_` is used.
3. Otherwise, the *default program* is used.
The default program is set automatically in the CLI. Library users can get and
set it manually. The default program is a per-thread setting. See `Thread
Safety`_.
.. drgndoc:: get_default_prog
.. drgndoc:: set_default_prog
.. drgndoc:: NoDefaultProgramError
For helpers, it is recommended to use the decorators from the
:mod:`drgn.helpers.common.prog` module instead.
Platforms
^^^^^^^^^
.. drgndoc:: Platform
.. drgndoc:: Architecture
.. drgndoc:: PlatformFlags
.. drgndoc:: Register
.. drgndoc:: host_platform
Languages
^^^^^^^^^
.. drgndoc:: Language
Objects
-------
.. drgndoc:: Object
.. drgndoc:: NULL
.. drgndoc:: cast
.. drgndoc:: reinterpret
.. drgndoc:: container_of
Symbols
-------
.. drgndoc:: Symbol
.. drgndoc:: SymbolBinding
.. drgndoc:: SymbolKind
Stack Traces
------------
Stack traces are retrieved with :func:`stack_trace()`,
:meth:`Program.stack_trace()`, or :meth:`Thread.stack_trace()`.
.. drgndoc:: stack_trace
.. drgndoc:: StackTrace
.. drgndoc:: StackFrame
.. _api-reference-types:
Types
-----
.. drgndoc:: Type
.. drgndoc:: TypeMember
.. drgndoc:: TypeEnumerator
.. drgndoc:: TypeParameter
.. drgndoc:: TypeTemplateParameter
.. drgndoc:: TypeKind
.. drgndoc:: PrimitiveType
.. drgndoc:: Qualifiers
.. drgndoc:: offsetof
.. _api-type-constructors:
Type Constructors
^^^^^^^^^^^^^^^^^
Custom drgn types can be created with the following factory functions. These
can be used just like types obtained from :meth:`Program.type()`.
.. drgndoc:: Program.void_type
.. drgndoc:: Program.int_type
.. drgndoc:: Program.bool_type
.. drgndoc:: Program.float_type
.. drgndoc:: Program.struct_type
.. drgndoc:: Program.union_type
.. drgndoc:: Program.class_type
.. drgndoc:: Program.enum_type
.. drgndoc:: Program.typedef_type
.. drgndoc:: Program.pointer_type
.. drgndoc:: Program.array_type
.. drgndoc:: Program.function_type
Miscellaneous
-------------
.. drgndoc:: sizeof
.. drgndoc:: execscript
.. drgndoc:: IntegerLike
.. drgndoc:: Path
Exceptions
----------
.. drgndoc:: FaultError
.. drgndoc:: MissingDebugInfoError
.. drgndoc:: ObjectAbsentError
.. drgndoc:: OutOfBoundsError
CLI
---
.. drgndoc:: cli
Logging
-------
drgn logs using the standard :mod:`logging` module to a logger named
``"drgn"``.
Thread Safety
-------------
Only one thread at a time should access the same :class:`Program` (including
:class:`Object`, :class:`Type`, :class:`StackTrace`, etc. from that program).
It is safe to use different :class:`Program`\ s from concurrent threads.