URL
https://opencores.org/ocsvn/openrisc/openrisc/trunk
Subversion Repositories openrisc
[/] [openrisc/] [trunk/] [gnu-old/] [gdb-7.1/] [gdb/] [doc/] [gdbint.info-2] - Rev 832
Go to most recent revision | Compare with Previous | Blame | View Log
This is gdbint.info, produced by makeinfo version 4.8 from
./gdbint.texinfo.
INFO-DIR-SECTION Software development
START-INFO-DIR-ENTRY
* Gdb-Internals: (gdbint). The GNU debugger's internals.
END-INFO-DIR-ENTRY
Copyright (C) 1990, 1991, 1992, 1993, 1994, 1996, 1998, 1999, 2000,
2001, 2002, 2003, 2004, 2005, 2006, 2008, 2009, 2010 Free Software
Foundation, Inc. Contributed by Cygnus Solutions. Written by John
Gilmore. Second Edition by Stan Shebs.
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.1 or
any later version published by the Free Software Foundation; with no
Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
Texts. A copy of the license is included in the section entitled "GNU
Free Documentation License".
This file documents the internals of the GNU debugger GDB.
Copyright (C) 1990, 1991, 1992, 1993, 1994, 1996, 1998, 1999, 2000,
2001, 2002, 2003, 2004, 2005, 2006, 2008, 2009, 2010 Free Software
Foundation, Inc. Contributed by Cygnus Solutions. Written by John
Gilmore. Second Edition by Stan Shebs.
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.1 or
any later version published by the Free Software Foundation; with no
Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
Texts. A copy of the license is included in the section entitled "GNU
Free Documentation License".
File: gdbint.info, Node: GDB Observers, Next: GNU Free Documentation License, Prev: Hints, Up: Top
Appendix A GDB Currently available observers
********************************************
A.1 Implementation rationale
============================
An "observer" is an entity which is interested in being notified when
GDB reaches certain states, or certain events occur in GDB. The entity
being observed is called the "subject". To receive notifications, the
observer attaches a callback to the subject. One subject can have
several observers.
`observer.c' implements an internal generic low-level event
notification mechanism. This generic event notification mechanism is
then re-used to implement the exported high-level notification
management routines for all possible notifications.
The current implementation of the generic observer provides support
for contextual data. This contextual data is given to the subject when
attaching the callback. In return, the subject will provide this
contextual data back to the observer as a parameter of the callback.
Note that the current support for the contextual data is only
partial, as it lacks a mechanism that would deallocate this data when
the callback is detached. This is not a problem so far, as this
contextual data is only used internally to hold a function pointer.
Later on, if a certain observer needs to provide support for user-level
contextual data, then the generic notification mechanism will need to be
enhanced to allow the observer to provide a routine to deallocate the
data when attaching the callback.
The observer implementation is also currently not reentrant. In
particular, it is therefore not possible to call the attach or detach
routines during a notification.
A.2 Debugging
=============
Observer notifications can be traced using the command `set debug
observer 1' (*note Optional messages about internal happenings:
(gdb)Debugging Output.).
A.3 `normal_stop' Notifications
===============================
GDB notifies all `normal_stop' observers when the inferior execution
has just stopped, the associated messages and annotations have been
printed, and the control is about to be returned to the user.
Note that the `normal_stop' notification is not emitted when the
execution stops due to a breakpoint, and this breakpoint has a
condition that is not met. If the breakpoint has any associated
commands list, the commands are executed after the notification is
emitted.
The following interfaces are available to manage observers:
-- Function: extern struct observer *observer_attach_EVENT
(observer_EVENT_ftype *F)
Using the function F, create an observer that is notified when
ever EVENT occurs, return the observer.
-- Function: extern void observer_detach_EVENT (struct observer
*OBSERVER);
Remove OBSERVER from the list of observers to be notified when
EVENT occurs.
-- Function: extern void observer_notify_EVENT (void);
Send a notification to all EVENT observers.
The following observable events are defined:
-- Function: void normal_stop (struct bpstats *BS, int PRINT_FRAME)
The inferior has stopped for real. The BS argument describes the
breakpoints were are stopped at, if any. Second argument
PRINT_FRAME non-zero means display the location where the inferior
has stopped.
-- Function: void target_changed (struct target_ops *TARGET)
The target's register contents have changed.
-- Function: void executable_changed (void)
The executable being debugged by GDB has changed: The user decided
to debug a different program, or the program he was debugging has
been modified since being loaded by the debugger (by being
recompiled, for instance).
-- Function: void inferior_created (struct target_ops *OBJFILE, int
FROM_TTY)
GDB has just connected to an inferior. For `run', GDB calls this
observer while the inferior is still stopped at the entry-point
instruction. For `attach' and `core', GDB calls this observer
immediately after connecting to the inferior, and before any
information on the inferior has been printed.
-- Function: void solib_loaded (struct so_list *SOLIB)
The shared library specified by SOLIB has been loaded. Note that
when GDB calls this observer, the library's symbols probably
haven't been loaded yet.
-- Function: void solib_unloaded (struct so_list *SOLIB)
The shared library specified by SOLIB has been unloaded. Note
that when GDB calls this observer, the library's symbols have not
been unloaded yet, and thus are still available.
-- Function: void new_objfile (struct objfile *OBJFILE)
The symbol file specified by OBJFILE has been loaded. Called with
OBJFILE equal to `NULL' to indicate previously loaded symbol table
data has now been invalidated.
-- Function: void new_thread (struct thread_info *T)
The thread specified by T has been created.
-- Function: void thread_exit (struct thread_info *T, int SILENT)
The thread specified by T has exited. The SILENT argument
indicates that GDB is removing the thread from its tables without
wanting to notify the user about it.
-- Function: void thread_stop_requested (ptid_t PTID)
An explicit stop request was issued to PTID. If PTID equals
MINUS_ONE_PTID, the request applied to all threads. If
`ptid_is_pid(ptid)' returns true, the request applied to all
threads of the process pointed at by PTID. Otherwise, the request
applied to the single thread pointed at by PTID.
-- Function: void target_resumed (ptid_t PTID)
The target was resumed. The PTID parameter specifies which thread
was resume, and may be RESUME_ALL if all threads are resumed.
-- Function: void about_to_proceed (void)
The target is about to be proceeded.
-- Function: void breakpoint_created (int BPNUM)
A new breakpoint has been created. The argument BPNUM is the
number of the newly-created breakpoint.
-- Function: void breakpoint_deleted (int BPNUM)
A breakpoint has been destroyed. The argument BPNUM is the number
of the newly-destroyed breakpoint.
-- Function: void breakpoint_modified (int BPNUM)
A breakpoint has been modified in some way. The argument BPNUM is
the number of the modified breakpoint.
-- Function: void tracepoint_created (int TPNUM)
A new tracepoint has been created. The argument TPNUM is the
number of the newly-created tracepoint.
-- Function: void tracepoint_deleted (int TPNUM)
A tracepoint has been destroyed. The argument TPNUM is the number
of the newly-destroyed tracepoint.
-- Function: void tracepoint_modified (int TPNUM)
A tracepoint has been modified in some way. The argument TPNUM is
the number of the modified tracepoint.
-- Function: void architecture_changed (struct gdbarch *NEWARCH)
The current architecture has changed. The argument NEWARCH is a
pointer to the new architecture.
-- Function: void thread_ptid_changed (ptid_t OLD_PTID, ptid_t
NEW_PTID)
The thread's ptid has changed. The OLD_PTID parameter specifies
the old value, and NEW_PTID specifies the new value.
-- Function: void inferior_appeared (int PID)
GDB has attached to a new inferior identified by PID.
-- Function: void inferior_exit (int PID)
Either GDB detached from the inferior, or the inferior exited.
The argument PID identifies the inferior.
-- Function: void memory_changed (CORE_ADDR ADDR, int LEN, const
bfd_byte *DATA)
Bytes from DATA to DATA + LEN have been written to the current
inferior at ADDR.
-- Function: void test_notification (int SOMEARG)
This observer is used for internal testing. Do not use. See
testsuite/gdb.gdb/observer.exp.
File: gdbint.info, Node: GNU Free Documentation License, Next: Index, Prev: GDB Observers, Up: Top
Appendix B GNU Free Documentation License
*****************************************
Version 1.2, November 2002
Copyright (C) 2000,2001,2002 Free Software Foundation, Inc.
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
Everyone is permitted to copy and distribute verbatim copies
of this license document, but changing it is not allowed.
0. PREAMBLE
The purpose of this License is to make a manual, textbook, or other
functional and useful document "free" in the sense of freedom: to
assure everyone the effective freedom to copy and redistribute it,
with or without modifying it, either commercially or
noncommercially. Secondarily, this License preserves for the
author and publisher a way to get credit for their work, while not
being considered responsible for modifications made by others.
This License is a kind of "copyleft", which means that derivative
works of the document must themselves be free in the same sense.
It complements the GNU General Public License, which is a copyleft
license designed for free software.
We have designed this License in order to use it for manuals for
free software, because free software needs free documentation: a
free program should come with manuals providing the same freedoms
that the software does. But this License is not limited to
software manuals; it can be used for any textual work, regardless
of subject matter or whether it is published as a printed book.
We recommend this License principally for works whose purpose is
instruction or reference.
1. APPLICABILITY AND DEFINITIONS
This License applies to any manual or other work, in any medium,
that contains a notice placed by the copyright holder saying it
can be distributed under the terms of this License. Such a notice
grants a world-wide, royalty-free license, unlimited in duration,
to use that work under the conditions stated herein. The
"Document", below, refers to any such manual or work. Any member
of the public is a licensee, and is addressed as "you". You
accept the license if you copy, modify or distribute the work in a
way requiring permission under copyright law.
A "Modified Version" of the Document means any work containing the
Document or a portion of it, either copied verbatim, or with
modifications and/or translated into another language.
A "Secondary Section" is a named appendix or a front-matter section
of the Document that deals exclusively with the relationship of the
publishers or authors of the Document to the Document's overall
subject (or to related matters) and contains nothing that could
fall directly within that overall subject. (Thus, if the Document
is in part a textbook of mathematics, a Secondary Section may not
explain any mathematics.) The relationship could be a matter of
historical connection with the subject or with related matters, or
of legal, commercial, philosophical, ethical or political position
regarding them.
The "Invariant Sections" are certain Secondary Sections whose
titles are designated, as being those of Invariant Sections, in
the notice that says that the Document is released under this
License. If a section does not fit the above definition of
Secondary then it is not allowed to be designated as Invariant.
The Document may contain zero Invariant Sections. If the Document
does not identify any Invariant Sections then there are none.
The "Cover Texts" are certain short passages of text that are
listed, as Front-Cover Texts or Back-Cover Texts, in the notice
that says that the Document is released under this License. A
Front-Cover Text may be at most 5 words, and a Back-Cover Text may
be at most 25 words.
A "Transparent" copy of the Document means a machine-readable copy,
represented in a format whose specification is available to the
general public, that is suitable for revising the document
straightforwardly with generic text editors or (for images
composed of pixels) generic paint programs or (for drawings) some
widely available drawing editor, and that is suitable for input to
text formatters or for automatic translation to a variety of
formats suitable for input to text formatters. A copy made in an
otherwise Transparent file format whose markup, or absence of
markup, has been arranged to thwart or discourage subsequent
modification by readers is not Transparent. An image format is
not Transparent if used for any substantial amount of text. A
copy that is not "Transparent" is called "Opaque".
Examples of suitable formats for Transparent copies include plain
ASCII without markup, Texinfo input format, LaTeX input format,
SGML or XML using a publicly available DTD, and
standard-conforming simple HTML, PostScript or PDF designed for
human modification. Examples of transparent image formats include
PNG, XCF and JPG. Opaque formats include proprietary formats that
can be read and edited only by proprietary word processors, SGML or
XML for which the DTD and/or processing tools are not generally
available, and the machine-generated HTML, PostScript or PDF
produced by some word processors for output purposes only.
The "Title Page" means, for a printed book, the title page itself,
plus such following pages as are needed to hold, legibly, the
material this License requires to appear in the title page. For
works in formats which do not have any title page as such, "Title
Page" means the text near the most prominent appearance of the
work's title, preceding the beginning of the body of the text.
A section "Entitled XYZ" means a named subunit of the Document
whose title either is precisely XYZ or contains XYZ in parentheses
following text that translates XYZ in another language. (Here XYZ
stands for a specific section name mentioned below, such as
"Acknowledgements", "Dedications", "Endorsements", or "History".)
To "Preserve the Title" of such a section when you modify the
Document means that it remains a section "Entitled XYZ" according
to this definition.
The Document may include Warranty Disclaimers next to the notice
which states that this License applies to the Document. These
Warranty Disclaimers are considered to be included by reference in
this License, but only as regards disclaiming warranties: any other
implication that these Warranty Disclaimers may have is void and
has no effect on the meaning of this License.
2. VERBATIM COPYING
You may copy and distribute the Document in any medium, either
commercially or noncommercially, provided that this License, the
copyright notices, and the license notice saying this License
applies to the Document are reproduced in all copies, and that you
add no other conditions whatsoever to those of this License. You
may not use technical measures to obstruct or control the reading
or further copying of the copies you make or distribute. However,
you may accept compensation in exchange for copies. If you
distribute a large enough number of copies you must also follow
the conditions in section 3.
You may also lend copies, under the same conditions stated above,
and you may publicly display copies.
3. COPYING IN QUANTITY
If you publish printed copies (or copies in media that commonly
have printed covers) of the Document, numbering more than 100, and
the Document's license notice requires Cover Texts, you must
enclose the copies in covers that carry, clearly and legibly, all
these Cover Texts: Front-Cover Texts on the front cover, and
Back-Cover Texts on the back cover. Both covers must also clearly
and legibly identify you as the publisher of these copies. The
front cover must present the full title with all words of the
title equally prominent and visible. You may add other material
on the covers in addition. Copying with changes limited to the
covers, as long as they preserve the title of the Document and
satisfy these conditions, can be treated as verbatim copying in
other respects.
If the required texts for either cover are too voluminous to fit
legibly, you should put the first ones listed (as many as fit
reasonably) on the actual cover, and continue the rest onto
adjacent pages.
If you publish or distribute Opaque copies of the Document
numbering more than 100, you must either include a
machine-readable Transparent copy along with each Opaque copy, or
state in or with each Opaque copy a computer-network location from
which the general network-using public has access to download
using public-standard network protocols a complete Transparent
copy of the Document, free of added material. If you use the
latter option, you must take reasonably prudent steps, when you
begin distribution of Opaque copies in quantity, to ensure that
this Transparent copy will remain thus accessible at the stated
location until at least one year after the last time you
distribute an Opaque copy (directly or through your agents or
retailers) of that edition to the public.
It is requested, but not required, that you contact the authors of
the Document well before redistributing any large number of
copies, to give them a chance to provide you with an updated
version of the Document.
4. MODIFICATIONS
You may copy and distribute a Modified Version of the Document
under the conditions of sections 2 and 3 above, provided that you
release the Modified Version under precisely this License, with
the Modified Version filling the role of the Document, thus
licensing distribution and modification of the Modified Version to
whoever possesses a copy of it. In addition, you must do these
things in the Modified Version:
A. Use in the Title Page (and on the covers, if any) a title
distinct from that of the Document, and from those of
previous versions (which should, if there were any, be listed
in the History section of the Document). You may use the
same title as a previous version if the original publisher of
that version gives permission.
B. List on the Title Page, as authors, one or more persons or
entities responsible for authorship of the modifications in
the Modified Version, together with at least five of the
principal authors of the Document (all of its principal
authors, if it has fewer than five), unless they release you
from this requirement.
C. State on the Title page the name of the publisher of the
Modified Version, as the publisher.
D. Preserve all the copyright notices of the Document.
E. Add an appropriate copyright notice for your modifications
adjacent to the other copyright notices.
F. Include, immediately after the copyright notices, a license
notice giving the public permission to use the Modified
Version under the terms of this License, in the form shown in
the Addendum below.
G. Preserve in that license notice the full lists of Invariant
Sections and required Cover Texts given in the Document's
license notice.
H. Include an unaltered copy of this License.
I. Preserve the section Entitled "History", Preserve its Title,
and add to it an item stating at least the title, year, new
authors, and publisher of the Modified Version as given on
the Title Page. If there is no section Entitled "History" in
the Document, create one stating the title, year, authors,
and publisher of the Document as given on its Title Page,
then add an item describing the Modified Version as stated in
the previous sentence.
J. Preserve the network location, if any, given in the Document
for public access to a Transparent copy of the Document, and
likewise the network locations given in the Document for
previous versions it was based on. These may be placed in
the "History" section. You may omit a network location for a
work that was published at least four years before the
Document itself, or if the original publisher of the version
it refers to gives permission.
K. For any section Entitled "Acknowledgements" or "Dedications",
Preserve the Title of the section, and preserve in the
section all the substance and tone of each of the contributor
acknowledgements and/or dedications given therein.
L. Preserve all the Invariant Sections of the Document,
unaltered in their text and in their titles. Section numbers
or the equivalent are not considered part of the section
titles.
M. Delete any section Entitled "Endorsements". Such a section
may not be included in the Modified Version.
N. Do not retitle any existing section to be Entitled
"Endorsements" or to conflict in title with any Invariant
Section.
O. Preserve any Warranty Disclaimers.
If the Modified Version includes new front-matter sections or
appendices that qualify as Secondary Sections and contain no
material copied from the Document, you may at your option
designate some or all of these sections as invariant. To do this,
add their titles to the list of Invariant Sections in the Modified
Version's license notice. These titles must be distinct from any
other section titles.
You may add a section Entitled "Endorsements", provided it contains
nothing but endorsements of your Modified Version by various
parties--for example, statements of peer review or that the text
has been approved by an organization as the authoritative
definition of a standard.
You may add a passage of up to five words as a Front-Cover Text,
and a passage of up to 25 words as a Back-Cover Text, to the end
of the list of Cover Texts in the Modified Version. Only one
passage of Front-Cover Text and one of Back-Cover Text may be
added by (or through arrangements made by) any one entity. If the
Document already includes a cover text for the same cover,
previously added by you or by arrangement made by the same entity
you are acting on behalf of, you may not add another; but you may
replace the old one, on explicit permission from the previous
publisher that added the old one.
The author(s) and publisher(s) of the Document do not by this
License give permission to use their names for publicity for or to
assert or imply endorsement of any Modified Version.
5. COMBINING DOCUMENTS
You may combine the Document with other documents released under
this License, under the terms defined in section 4 above for
modified versions, provided that you include in the combination
all of the Invariant Sections of all of the original documents,
unmodified, and list them all as Invariant Sections of your
combined work in its license notice, and that you preserve all
their Warranty Disclaimers.
The combined work need only contain one copy of this License, and
multiple identical Invariant Sections may be replaced with a single
copy. If there are multiple Invariant Sections with the same name
but different contents, make the title of each such section unique
by adding at the end of it, in parentheses, the name of the
original author or publisher of that section if known, or else a
unique number. Make the same adjustment to the section titles in
the list of Invariant Sections in the license notice of the
combined work.
In the combination, you must combine any sections Entitled
"History" in the various original documents, forming one section
Entitled "History"; likewise combine any sections Entitled
"Acknowledgements", and any sections Entitled "Dedications". You
must delete all sections Entitled "Endorsements."
6. COLLECTIONS OF DOCUMENTS
You may make a collection consisting of the Document and other
documents released under this License, and replace the individual
copies of this License in the various documents with a single copy
that is included in the collection, provided that you follow the
rules of this License for verbatim copying of each of the
documents in all other respects.
You may extract a single document from such a collection, and
distribute it individually under this License, provided you insert
a copy of this License into the extracted document, and follow
this License in all other respects regarding verbatim copying of
that document.
7. AGGREGATION WITH INDEPENDENT WORKS
A compilation of the Document or its derivatives with other
separate and independent documents or works, in or on a volume of
a storage or distribution medium, is called an "aggregate" if the
copyright resulting from the compilation is not used to limit the
legal rights of the compilation's users beyond what the individual
works permit. When the Document is included in an aggregate, this
License does not apply to the other works in the aggregate which
are not themselves derivative works of the Document.
If the Cover Text requirement of section 3 is applicable to these
copies of the Document, then if the Document is less than one half
of the entire aggregate, the Document's Cover Texts may be placed
on covers that bracket the Document within the aggregate, or the
electronic equivalent of covers if the Document is in electronic
form. Otherwise they must appear on printed covers that bracket
the whole aggregate.
8. TRANSLATION
Translation is considered a kind of modification, so you may
distribute translations of the Document under the terms of section
4. Replacing Invariant Sections with translations requires special
permission from their copyright holders, but you may include
translations of some or all Invariant Sections in addition to the
original versions of these Invariant Sections. You may include a
translation of this License, and all the license notices in the
Document, and any Warranty Disclaimers, provided that you also
include the original English version of this License and the
original versions of those notices and disclaimers. In case of a
disagreement between the translation and the original version of
this License or a notice or disclaimer, the original version will
prevail.
If a section in the Document is Entitled "Acknowledgements",
"Dedications", or "History", the requirement (section 4) to
Preserve its Title (section 1) will typically require changing the
actual title.
9. TERMINATION
You may not copy, modify, sublicense, or distribute the Document
except as expressly provided for under this License. Any other
attempt to copy, modify, sublicense or distribute the Document is
void, and will automatically terminate your rights under this
License. However, parties who have received copies, or rights,
from you under this License will not have their licenses
terminated so long as such parties remain in full compliance.
10. FUTURE REVISIONS OF THIS LICENSE
The Free Software Foundation may publish new, revised versions of
the GNU Free Documentation License from time to time. Such new
versions will be similar in spirit to the present version, but may
differ in detail to address new problems or concerns. See
`http://www.gnu.org/copyleft/'.
Each version of the License is given a distinguishing version
number. If the Document specifies that a particular numbered
version of this License "or any later version" applies to it, you
have the option of following the terms and conditions either of
that specified version or of any later version that has been
published (not as a draft) by the Free Software Foundation. If
the Document does not specify a version number of this License,
you may choose any version ever published (not as a draft) by the
Free Software Foundation.
B.1 ADDENDUM: How to use this License for your documents
========================================================
To use this License in a document you have written, include a copy of
the License in the document and put the following copyright and license
notices just after the title page:
Copyright (C) YEAR YOUR NAME.
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.2
or any later version published by the Free Software Foundation;
with no Invariant Sections, no Front-Cover Texts, and no Back-Cover
Texts. A copy of the license is included in the section entitled ``GNU
Free Documentation License''.
If you have Invariant Sections, Front-Cover Texts and Back-Cover
Texts, replace the "with...Texts." line with this:
with the Invariant Sections being LIST THEIR TITLES, with
the Front-Cover Texts being LIST, and with the Back-Cover Texts
being LIST.
If you have Invariant Sections without Cover Texts, or some other
combination of the three, merge those two alternatives to suit the
situation.
If your document contains nontrivial examples of program code, we
recommend releasing these examples in parallel under your choice of
free software license, such as the GNU General Public License, to
permit their use in free software.
File: gdbint.info, Node: Index, Prev: GNU Free Documentation License, Up: Top
Index
*****