4 - Each DSO can now ship an ltrace config file (called prototype
5 library) that ltrace will open when that DSO is loaded to process
6 image. See ltrace(1) for details.
8 - ltrace.conf is no longer part of installation tarball. Instead,
9 we now ship libc.so.conf, libm.so.conf, libacl.so.conf, and
10 syscalls.conf. Those are now istalled to /usr/share/ltrace by
11 default. /etc/ltrace.conf and $HOME/.ltrace.conf are still
12 loaded if present, and can contain arbitrary user configuration.
14 - The option -F was retrofitted to be a colon-separated list of
15 prototype libraries, and directories to look for prototype
16 libraries in. On Linux, ltrace looks into XDG_CONFIG_HOME,
17 XDG_CONFIG_DIRS, and /usr/share/ltrace as well.
19 - Wide character strings are supported in prototypes. Use "string"
20 lens as usual, but use array of integers as underlying type.
21 libc.so.conf now contains prototypes of wide character functions.
23 - Sole void function parameter such as in the following example, is
24 now considered obsolete:
28 This use is still accepted, taken to mean "hide(int)", but
29 produces a warning, and will be removed in future.
31 ** Architectural support
32 - MIPS and MIPSel are now handled by the same backend.
33 - ARMv6, ARMv7 and ARMv8 (AArch64) are supported, including full
34 fetch backend. ARMv8 backend doesn't support tracing of 32-bit
35 binaries, as currently there's no 32-bit userspace available for
37 - Imagination Technologies Meta is now supported.
39 - On Linux, tracing of IFUNC symbols is supported. On i386,
40 x86_64, ppc32 with secure PLT and ppc64, IRELATIVE PLT slots are
43 ** -w output now shows full library path
44 The output format is similar to glibc's backtrace_symbols, e.g.:
45 > /bin/ls(_init+0x19be) [0x40398e]
46 > /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xed) [0x7f50cbc3676d]
47 > /bin/ls(_init+0x25fd) [0x4045cd]
49 * Version 0.7.3 [2013-09-15 Sun]
51 *** [MIPS] Fix build on mips big endian
52 This bug caused messages like:
54 | /bin/sh: line 17: cd: mips: No such file or directory
55 *** [MIPS] Fix SIGSEGV on mips big endian
56 This bug caused runtime messages like:
57 | [0x4000000] --- SIGSEGV (Segmentation fault) ---
58 | [0xffffffff] +++ killed by SIGSEGV +++
59 *** Fix build with CLANG on FREEBSD
61 * Version 0.7.2 [2012-12-07 Fri]
63 *** (Again) detect VDSO entry in r_debug linkmap with non-empty name
64 This bug caused messages like:
65 | Couldn't determine base address of linux-vdso32.so.1
66 | Couldn't load ELF object linux-vdso32.so.1: No such file or directory
67 *** Fix building with libunwind 1.1
68 *** Fix prototype lookup for -x symbols from shared libraries
69 Ltrace was unable to find prototypes of static symbols in shared
70 libraries. It changed the symbol name internally to the form
71 name@libfoo.so. Thus mangled, symbols were not found in config
74 * Version 0.7.1 [2012-11-29 Thu]
76 *** ltrace.conf.5 is now installed to man5 as it should be
77 *** [PowerPC] A header file necessary for building is now shipped
78 *** [MIPS] Work around duplicate symbol request bug
79 This fixes the ltrace abort:
80 | ./ltrace: proc.c: 755: breakpoint_for_symbol: Assertion `bp->libsym == ((void *)0)' failed.
82 *** Detect VDSO entry in r_debug linkmap with non-empty name
83 This bug caused messages like:
84 | Couldn't determine base address of linux-vdso32.so.1
85 | Couldn't load ELF object linux-vdso32.so.1: No such file or directory
87 *** Temporary files are wiped properly after the test suite has been run
88 *** Parsing typedefs with common prefix now works as it should
89 More exactly, if there were typedefs X and XY (in this order), and
90 a reference was made to X, ltrace would match XY instead.
93 *** The following prototypes in ltrace.conf were added or updated
94 __ctype_get_mb_cur_max, __endmntent, __getmntent_r, __setmntent,
95 a64l, abort, abs, addmntent, getmntent_r, hasmntopt, inet_addr,
96 inet_aton, inet_lnaof, inet_makeaddr, inet_netof, inet_network,
97 inet_ntoa, kill, l64a, labs, memcpy, memmove, setlocale,
98 sigaction, sigaddset, sigandset, sigdelset, sigemptyset,
99 sigfillset, sigisemptyset, sigismember, signal, sigorset,
100 sigpending, sigprocmask, sigsuspend.
102 *** Duplicate typedefs are now guarded against
103 *** It's now possible to define recursive structures
104 Please read ltrace.conf(5) man page, chapter "recursive
105 structures", to learn about this new feature.
107 *** New lens "bitvec" is available
108 This allows displaying various data types as bit vectors. Please
109 read ltrace.conf(5) to learn more.
111 *** Octal lens renamed to "oct"
112 For reasons of consistency with "hex". "octal" is still valid and
113 will be for forseeable future.
115 *** The hex lens can now format floating point arguments
117 * Version 0.7.0 [2012-11-09 Fri]
119 *** Full support for tracing multi-threaded processes
121 Ltrace now understands thread groups, and it stops all threads
122 before manipulating breakpoints. The downside is that performance
123 of multi-threaded processes is rather bad, because handling any
124 event implies stopping the whole job. The upside is that
125 individual threads don't get random SIGILL's and SIGSEGV's and
126 events are not missed.
128 *** Support for tracing inter-library calls
130 -e and -x were extended to allow library selectors. See the man
133 *** Better support for parameter passing ("fetch backend")
135 This version brings more complete support for parameter passing,
136 including passing structures in registers, passing double on i386,
137 and other edge cases that were not handled correctly before. The
138 following architectures now have implementation of fetch backend:
139 i386, x86_64, ppc, ppc64, ia64, s390, s390x, m68k.
141 *** Awareness of deny_ptrace SELinux boolean
143 The deny_ptrace boolean denies all processes from being able to
144 use ptrace to manipulate other processes. Ltrace now understands
145 that this boolean exists, and recommends turning it off, if it is
146 on and ltrace fails to attach to a process.
148 *** Limited support for tracing returns from tail call functions
149 *** -e, -x and -l selectors now allow using globs and regular expressions
151 See the man page for details of the selector syntax. This changes
152 the way -x and -l behave with respect to tracing libraries opened
155 - In 0.6.0, only those -x symbols that were unmatched in main
156 binary were used to search through symbol table of libraries
157 opened with dlopen. In 0.7.0, -x and -e are applied uniformly
158 to each mapped binary: the main binary, dependent DSO's, and any
161 - In 0.6.0, -l argument was a filename to open and inspect. In
162 0.7.0, -l is a glob expression matched against each mapped
165 *** -g command line option dropped
167 This option was introduced in 0.6.0 with the meaning identical to
168 -L, which should be used instead.
170 *** Test suite can now be run under valgrind
172 Use --enable-valgrind to turn this on.
174 *** [ppc] Support both BSS and secure PLTs for 32-bit processes
175 *** [mips] Implement software singlestepping
176 *** [mips] Add support for CPIC main programs
177 *** Support tracing PIE binaries
179 ** Configuration Files
181 *** New abstraction: parameter pack
183 Parameter packs describe zero or more of actual arguments, whose
184 type can be determined in runtime. The only parameter pack
185 currently implemented is "format" for decoding printf-style format
188 In future, it should be relatively straightforward to add more
189 parameter packs for functions like execl, and others.
191 *** New expression: zero
193 When used in array length expressions, it means "this array ends
194 at the first element with zero value". C strings are essentially
197 *** Lenses: change the way that underlying type is rendered
199 Lenses are used similarly to parametrized types, e.g.:
200 | void func(lens(int)); |
204 "octal", which used to be a separate type, is now lens, which can
205 be used to render any underlying type in base 8. Plain "octal"
206 is still valid and means the same thing as "octal(int)".
210 Similarly, "hex" lens was introduced to format as base 16.
211 "hide" was introduced to conceal given argument. "bool" lens was
212 added to format objects as either true, or false.
216 "enum" became lens as well. Because enum already uses
217 parentheses to denote the list of enumeration values, the
218 underlying type is selected by square brackets:
220 | void func(enum[short](RED,GREEN,BLUE)); |
224 "string" was also turned to lens. The argument can be either a
225 char*, or pointer to array of char, or array of char. The latter
226 is useful in cases like the following:
228 | void func_struct_2(struct(string(array(char, 6)))); |
230 *** Misspelling of "int" as "itn" temporarily accepted, but deprecated
232 Pre-0.7 ltrace shipped a buggy version of ltrace.conf that
233 contained the following prototype:
235 | itn acl_valid(addr); |
237 To support extant versions of ltrace.conf, that use is now
238 considered valid, and "itn" is a synonym of "int". It is however
239 deprecated, and will produce a warning in future.
241 *** Using void as top-level function argument now deprecated
243 Functions that take no arguments shouldn't pretend to take one
244 parameter of void type. For example the following:
248 ... should be declared like this:
252 To support extant versions of ltrace.conf, that use is now
253 considered valid. It is however deprecated, and will produce a
256 *** Using void to hide one argument is now obsolete
258 Ltrace needs to know the exact underlying type to decide what the
259 calling convention is. The use of void to mean "hide this
260 argument", such as the following example, is therefore obsolete:
262 | void func(void, array(int, arg1)); |
264 Instead, rewrite the prototype depending on the exact underlying
267 | void func(hide(int), array(int, arg1)); |
268 | void func(hide(long), array(int, arg1)); |
270 To support extant versions of ltrace.conf, this use is still
271 accepted, and "void" is taken to mean "hide(int)". It is however
272 obsolete, produces a warning, and will be removed in future.
276 *** New manual page ltrace.conf(5)
277 *** README, INSTALL brought up to date
278 *** New file CREDITS with a list of contributors
282 *** Fix detaching from a process
284 Earlier, a process that ltrace detached from would sometimes die
285 of SIGSEGV, SIGTRAP, or SIGILL. These were caused by ltrace
286 detaching from the process just after that process hit a
287 breakpoint. Program counter would thus be left pointing
288 mid-instruction, or signals would be left pending.
290 *** Argument to -n is now checked for validity
291 *** Fix tracing across exec in a stripped binary
292 *** [x86] ORIG_RAX/ORIG_EAX may not contain original syscall number
294 In cases where the system call shouldn't be restarted, these are
295 set to -1. In that case assume that the return is from the
296 topmost syscall. This gets rid of some "unexpected breakpoint"
297 messages on x86_64 and i386.
299 *** [ppc] Fix races in tracing -e events in 64-bit processes
301 On ppc, the contents of PLT table change after the first call.
302 Ltrace used to handle this by reinserting the (now overwritten)
303 breakpoint after the function returns. This introduced a window
304 where calls to the same function from the same binary (either a
305 recursive calls, or calls from another thread) weren't traced.
306 This is fixed as of 0.7.0.
308 As a side effect, events requested via -e now only hit when a PLT
309 call is made, which is consistent with other architectures.
311 *** [ppc] Allow stepping over lwarx instruction
315 *** [arm] Tracing is not supported at all on ARM
317 ltrace might work on older kernels, but no attempt was made to
318 fully support it. Newer kernels don't support PTRACE_SINGLESTEP,
319 which ltrace depends on. Before singlestepping is implemented in
320 software, ARM is considered unsupported.
322 * Version 0.6.0 [2011-01-06 Thu]
326 *** Use autotools for building
327 *** New option -b: disables output of signals received by the tracee
328 *** New option -w: print stack trace of events
330 Pass --with-libunwind to configure to enable the feature. This
333 *** Support tracing of symbols from libraries opened with dlopen
335 These symbols are selected by -x.
337 ** Architecture-specific Changes
339 *** Various fixes for MIPS and PowerPC
340 *** Support for ARM Thumb mode
341 *** Implement fetching of 5th and further function arguments on s390
342 *** Support fork/exec syscalls on 31-bit s390
343 *** Support for float and double arguments on x86_64
344 *** Fixes for return arguments (after '+') in nested calls on x86_64
347 -------------------------------------------------------------------------------
348 Copyright (C) 2012-2014 Petr Machata <pmachata@redhat.com>
349 This file is part of ltrace.
351 ltrace is free software; you can redistribute it and/or modify it
352 under the terms of the GNU General Public License as published by the
353 Free Software Foundation; either version 2 of the License, or (at your
354 option) any later version.
356 ltrace is distributed in the hope that it will be useful, but WITHOUT
357 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
358 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
361 You should have received a copy of the GNU General Public License
362 along with this program. If not, see <http://www.gnu.org/licenses/>.