xref: /freebsd/lib/librtld_db/librtld_db.3 (revision 40a8ac8f62b535d30349faf28cf47106b7041b83)
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31.Dd June 10, 2010
32.Dt LIBRTLD_DB 3
33.Os
34.Sh NAME
35.Nm librtld_db
36.Nd library for run-time linker debugging
37.Sh LIBRARY
38.Lb librtld_db
39.Sh SYNOPSIS
40.In rtld_db.h
41.Ft void
42.Fo rd_delete
43.Fa "rd_agent_t *rdap"
44.Fc
45.Ft char *
46.Fo rd_errstr
47.Fa "rd_err_e rderr"
48.Fc
49.Ft rd_err_e
50.Fo rd_event_addr
51.Fa "rd_agent_t *rdap, rd_event_e event, rd_notify_t *notify"
52.Fc
53.Ft rd_err_e
54.Fo rd_event_enable
55.Fa "rd_agent_t *rdap, int onoff"
56.Fc
57.Ft rd_err_e
58.Fo rd_event_getmsg
59.Fa "rd_agent_t *rdap, rd_event_msg_t *msg"
60.Fc
61.Ft rd_err_e
62.Fo rd_init
63.Fa "int version"
64.Fc
65.Ft typedef int
66.Fo rl_iter_f
67.Fa "const rd_loadobj_t *, void *"
68.Fc
69.Ft rd_err_e
70.Fo rd_loadobj_iter
71.Fa "rd_agent_t *rdap, rl_iter_f *cb, void *clnt_data"
72.Fc
73.Ft void
74.Fo rd_log
75.Fa "const int onoff"
76.Fc
77.Ft rd_agent_t *
78.Fo rd_new
79.Fa "struct proc_handle *php"
80.Fc
81.Ft rd_err_e
82.Fo rd_objpad_enable
83.Fa "rd_agent_t *rdap, size_t padsize"
84.Fc
85.Ft rd_err_e
86.Fo rd_plt_resolution
87.Fa "rd_agent_t *rdap, uintptr_t pc, struct proc *proc"
88.Fa "uintptr_t plt_base, rd_plt_info_t *rpi"
89.Fc
90.Ft rd_err_e
91.Fo rd_reset
92.Fa "rd_agent_t *rdap"
93.Fc
94.Sh DESCRIPTION
95The
96.Nm librtld_db
97library provides a debugging interface to the run-time linker (rtld).
98This library must be used along with
99.Xr libproc 3 .
100.Pp
101Most library functions take a
102.Ft rd_agent_t
103argument.
104This argument is an opaque structure containing information associated with
105the current status of the agent.
106.Pp
107Before you start using
108.Nm
109you should call
110.Fn rd_init
111with the
112.Ft RD_VERSION
113argument.
114This initializes the library to the correct version your program was compiled
115with and provides proper ABI stability.
116.Pp
117What follows is a description of what each function.
118.Pp
119.Fn rd_new
120creates a new
121.Nm
122agent.
123The
124.Ft php
125argument should be the
126.Ft proc_handle
127you received from
128.Xr libproc 3 .
129.Pp
130.Fn rd_reset
131resets your previously created agent.
132.Pp
133.Fn rd_delete
134deallocates the resources associated with the agent.
135.Pp
136.Fn rd_errstr
137returns an error string describing the error present in
138.Ft rderr .
139.Pp
140.Fn rd_event_enable
141enables reporting of events.
142This function always returns RD_OK.
143.Pp
144.Fn rd_event_addr
145returns the event address corresponding to the
146.Ft event
147parameter.
148At the moment we only report events of type RD_NOTIFY_BPT.
149.Pp
150.Fn rd_event_getmsg
151returns the message associated with the latest event.
152At the moment only RD_POSTINIT events are supported.
153.Pp
154.Fn rd_loadobj_iter
155allows you to iterate over the program's loaded objects.
156.Ft cb
157is a callback of type
158.Fn rl_iter_f .
159.Sh RETURN VALUES
160Most functions return an
161.Ft rd_err_e
162type error.
163The error codes are described in the header file for this library.
164You can get the error string using
165.Fn rd_errstr .
166.Sh SEE ALSO
167.Xr ld 1 ,
168.Xr ld-elf.so.1 1 ,
169.Xr ld.so 1 ,
170.Xr libproc 3 ,
171.Xr rtld 1
172.Sh HISTORY
173The
174.Nm librtld_db
175library first appeared in
176.Fx 9.0
177and was modeled after the same library present in the Solaris operating system.
178.Sh AUTHORS
179The
180.Nm librtld_db
181library and this manual page were written by
182.An Rui Paulo Aq Mt rpaulo@FreeBSD.org
183under sponsorship from the FreeBSD Foundation.
184.Sh CAVEATS
185The functions
186.Fn rd_event_enable ,
187.Fn rd_log ,
188.Fn rd_objpad_enable
189and
190.Fn rd_plt_resolution
191are not yet implemented.
192