xref: /freebsd/lib/librtld_db/librtld_db.3 (revision 315ee00f)
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29.Dd June 10, 2010
30.Dt LIBRTLD_DB 3
31.Os
32.Sh NAME
33.Nm librtld_db
34.Nd library for run-time linker debugging
35.Sh LIBRARY
36.Lb librtld_db
37.Sh SYNOPSIS
38.In rtld_db.h
39.Ft void
40.Fo rd_delete
41.Fa "rd_agent_t *rdap"
42.Fc
43.Ft char *
44.Fo rd_errstr
45.Fa "rd_err_e rderr"
46.Fc
47.Ft rd_err_e
48.Fo rd_event_addr
49.Fa "rd_agent_t *rdap, rd_event_e event, rd_notify_t *notify"
50.Fc
51.Ft rd_err_e
52.Fo rd_event_enable
53.Fa "rd_agent_t *rdap, int onoff"
54.Fc
55.Ft rd_err_e
56.Fo rd_event_getmsg
57.Fa "rd_agent_t *rdap, rd_event_msg_t *msg"
58.Fc
59.Ft rd_err_e
60.Fo rd_init
61.Fa "int version"
62.Fc
63.Ft typedef int
64.Fo rl_iter_f
65.Fa "const rd_loadobj_t *, void *"
66.Fc
67.Ft rd_err_e
68.Fo rd_loadobj_iter
69.Fa "rd_agent_t *rdap, rl_iter_f *cb, void *clnt_data"
70.Fc
71.Ft void
72.Fo rd_log
73.Fa "const int onoff"
74.Fc
75.Ft rd_agent_t *
76.Fo rd_new
77.Fa "struct proc_handle *php"
78.Fc
79.Ft rd_err_e
80.Fo rd_objpad_enable
81.Fa "rd_agent_t *rdap, size_t padsize"
82.Fc
83.Ft rd_err_e
84.Fo rd_plt_resolution
85.Fa "rd_agent_t *rdap, uintptr_t pc, struct proc *proc"
86.Fa "uintptr_t plt_base, rd_plt_info_t *rpi"
87.Fc
88.Ft rd_err_e
89.Fo rd_reset
90.Fa "rd_agent_t *rdap"
91.Fc
92.Sh DESCRIPTION
93The
94.Nm librtld_db
95library provides a debugging interface to the run-time linker (rtld).
96This library must be used along with
97.Xr libproc 3 .
98.Pp
99Most library functions take a
100.Ft rd_agent_t
101argument.
102This argument is an opaque structure containing information associated with
103the current status of the agent.
104.Pp
105Before you start using
106.Nm
107you should call
108.Fn rd_init
109with the
110.Ft RD_VERSION
111argument.
112This initializes the library to the correct version your program was compiled
113with and provides proper ABI stability.
114.Pp
115What follows is a description of what each function.
116.Pp
117.Fn rd_new
118creates a new
119.Nm
120agent.
121The
122.Ft php
123argument should be the
124.Ft proc_handle
125you received from
126.Xr libproc 3 .
127.Pp
128.Fn rd_reset
129resets your previously created agent.
130.Pp
131.Fn rd_delete
132deallocates the resources associated with the agent.
133.Pp
134.Fn rd_errstr
135returns an error string describing the error present in
136.Ft rderr .
137.Pp
138.Fn rd_event_enable
139enables reporting of events.
140This function always returns RD_OK.
141.Pp
142.Fn rd_event_addr
143returns the event address corresponding to the
144.Ft event
145parameter.
146At the moment we only report events of type RD_NOTIFY_BPT.
147.Pp
148.Fn rd_event_getmsg
149returns the message associated with the latest event.
150At the moment only RD_POSTINIT events are supported.
151.Pp
152.Fn rd_loadobj_iter
153allows you to iterate over the program's loaded objects.
154.Ft cb
155is a callback of type
156.Fn rl_iter_f .
157.Sh RETURN VALUES
158Most functions return an
159.Ft rd_err_e
160type error.
161The error codes are described in the header file for this library.
162You can get the error string using
163.Fn rd_errstr .
164.Sh SEE ALSO
165.Xr ld 1 ,
166.Xr ld-elf.so.1 1 ,
167.Xr ld.so 1 ,
168.Xr rtld 1 ,
169.Xr libproc 3
170.Sh HISTORY
171The
172.Nm librtld_db
173library first appeared in
174.Fx 9.0
175and was modeled after the same library present in the Solaris operating system.
176.Sh AUTHORS
177The
178.Nm librtld_db
179library and this manual page were written by
180.An Rui Paulo Aq Mt rpaulo@FreeBSD.org
181under sponsorship from the FreeBSD Foundation.
182.Sh CAVEATS
183The functions
184.Fn rd_event_enable ,
185.Fn rd_log ,
186.Fn rd_objpad_enable
187and
188.Fn rd_plt_resolution
189are not yet implemented.
190