1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
|
.\"
.\" Copyright (c) 1994 University of Maryland
.\" All Rights Reserved.
.\"
.\" Permission to use, copy, modify, distribute, and sell this software and its
.\" documentation for any purpose is hereby granted without fee, provided that
.\" the above copyright notice appear in all copies and that both that
.\" copyright notice and this permission notice appear in supporting
.\" documentation, and that the name of U.M. not be used in advertising or
.\" publicity pertaining to distribution of the software without specific,
.\" written prior permission. U.M. makes no representations about the
.\" suitability of this software for any purpose. It is provided "as is"
.\" without express or implied warranty.
.\"
.\" U.M. DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL U.M.
.\" BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR
.\" IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
.\"
.\" Author: James da Silva, Systems Design and Analysis Group
.\" Computer Science Department
.\" University of Maryland at College Park
.\"
.Dd June 14, 1994
.Dt CRUNCHGEN 1
.Os BSD 4
.Sh NAME
.Nm \&crunchgen
.Nd generates build environment for a crunched binary
.Sh SYNOPSIS
.Nm \&crunchgen
.Op Fl fql
.Op Fl m Ar makefile-name
.Op Fl c Ar c-file-name
.Op Fl e Ar exec-file-name
.Op Ar conf-file
.Sh DESCRIPTION
A crunched binary is a program made up of many other programs linked
together into a single executable. The crunched binary main()
function determines which component program to run by the contents of
argv[0]. The main reason to crunch programs together is for fitting
as many programs as possible onto an installation or system recovery
floppy.
.Pp
.Nm Crunchgen
reads in the specifications in
.Ar conf-file
for a crunched binary, and generates a Makefile and accompanying
top-level C source file that when built create the crunched executable
file from the component programs. For each component program,
.Nm crunchgen
can optionally attempt to determine the object (.o) files that make up
the program from its source directory Makefile. This information is
cached between runs.
.Nm Crunchgen
uses the companion program
.Nm crunchide
to eliminate link-time conflicts between the component programs by
hiding all unnecessary symbols.
.Pp
After
.Nm crunchgen
is run, the crunched binary can be built by running ``make -f
<conf-name>.mk''. The component programs' object files must already
be built. A ``objs'' target, included in the output makefile, will
run make in each component program's source dir to build the object
files for the user. This is not done automatically since in release
engineering circumstances it is generally not desirable to be
modifying objects in other directories.
.Pp
The options are as follows:
.Bl -tag -width indent
.It Fl c Ar c-file-name
Set output C file name to
.Ar c-file-name .
The default name is ``<conf-name>.c''.
.It Fl e Ar exec-file-name
Set crunched binary executable file name to
.Ar exec-file-name .
The default name is ``<conf-name>''.
.It Fl f
Flush cache. Forces the recalculation of cached parameters.
.It Fl l
List names. Lists the names this binary will respond to.
.It Fl m Ar makefile-name
Set output Makefile name to
.Ar makefile-name .
The default name is ``<conf-name>.mk''.
.It Fl q
Quiet operation. Status messages are suppressed.
.El
.Sh CRUNCHGEN CONFIGURATION FILE COMMANDS
.Nm Crunchgen
reads specifications from the
.Ar conf-file
that describe the components of the crunched binary. In its simplest
use, the component program names are merely listed along with the
top-level source directories in which their sources can be found.
.Nm Crunchgen
then calculates (via the source makefiles) and caches the
list of object files and their locations. For more specialized
situations, the user can specify by hand all the parameters that
.Nm crunchgen
needs.
.Pp
The
.Ar conf-file
commands are as follows:
.Bl -tag -width indent
.It Nm srcdirs Ar dirname ...
A list of source trees in which the source directories of the
component programs can be found. These dirs are searched using the
BSD ``<source-dir>/<progname>/'' convention. Multiple
.Nm srcdirs
lines can be specified. The directories are searched in the order
they are given.
.It Nm progs Ar progname ...
A list of programs that make up the crunched binary. Multiple
.Nm progs
lines can be specified.
.It Nm libs Ar libspec ...
A list of library specifications to be included in the crunched binary link.
Multiple
.Nm libs
lines can be specified.
.It Nm ln Ar progname linkname
Causes the crunched binary to invoke
.Ar progname
whenever
.Ar linkname
appears in argv[0]. This allows programs that change their behavior when
run under different names to operate correctly.
.El
To handle specialized situations, such as when the source is not
available or not built via a conventional Makefile, the following
.Nm special
commands can be used to set
.Nm crunchgen
parameters for a component program.
.Bl -tag -width indent
.It Nm special Ar progname Nm srcdir Ar pathname
Set the source directory for
.Ar progname .
This is normally calculated by searching the specified
.Nm srcdirs
for a directory named
.Ar progname .
.It Nm special Ar progname Nm objdir Ar pathname
Set the obj directory for
.Ar progname .
This is normally calculated by looking for a directory named
.Dq Pa obj
under the
.Ar srcdir ,
and if that is not found, the
.Ar srcdir
itself becomes the
.Ar objdir .
.It Nm special Ar progname Nm objs Ar object-file-name ...
Set the list of object files for program
.Ar progname .
This is normally calculated by constructing a temporary makefile that includes
.Dq Nm srcdir / Pa Makefile
and outputs the value of $(OBJS).
.It Nm special Ar progname Nm objpaths Ar full-pathname-to-object-file ...
Sets the pathnames of the object files for program
.Ar progname .
This is normally calculated by prepending the
.Nm objdir
pathname to each file in the
.Nm objs
list.
.El
.Pp
Only the
.Nm objpaths
parameter is actually needed by
.Nm crunchgen ,
but it is calculated from
.Nm objdir
and
.Nm objs ,
which are in turn calculated from
.Nm srcdir ,
so is sometimes convenient to specify the earlier parameters and let
.Nm crunchgen
calculate forward from there if it can.
.Pp
The makefile produced by
.Nm crunchgen
contains an optional
.Ar objs
target that will build the object files for each component program by
running make inside that program's source directory. For this to work the
.Nm srcdir
and
.Nm objs
parameters must also be valid. If they are not valid for a particular program, that
program is skipped in the
.Ar objs
target.
.Sh EXAMPLE
Here is an example
.Nm crunchgen
input conf file, named
.Dq Pa kcopy.conf :
.Pp
.nf
srcdirs /usr/src/bin /usr/src/sbin
progs test cp echo sh fsck halt init mount umount myinstall
ln test [ # test can be invoked via [
ln sh -sh # init invokes the shell with "-sh" in argv[0]
special myprog objpaths /homes/leroy/src/myinstall.o # no sources
libs -lutil -lcrypt
.fi
.Pp
This conf file specifies a small crunched binary consisting of some
basic system utilities plus a homegrown install program ``myinstall'',
for which no source directory is specified, but its object file is
specified directly with the
.Nm special
line.
.Pp
The crunched binary ``kcopy'' can be built as follows:
.Pp
.nf
% crunchgen -m Makefile kcopy.conf # gen Makefile and kcopy.c
% make objs # build the component programs' .o files
% make # build the crunched binary kcopy
% kcopy sh # test that this invokes a sh shell
$ # it works!
.fi
.Pp
At this point the binary ``kcopy'' can be copied onto an install floppy
and hard-linked to the names of the component programs.
.Sh SEE ALSO
.Xr crunchide 1
.Sh CAVEATS
While
.Nm crunch
takes care to eliminate link conflicts between the component programs
of a crunched binary, conflicts are still possible between the
libraries that are linked in. Some shuffling in the order of
libraries may be required, and in some rare cases two libraries may
have an unresolvable conflict and thus cannot be crunched together.
.Pp
Some versions of the BSD build environment do not by default build the
intermediate object file for single-source file programs. The ``make
objs'' target must then be used to get those object files built, or
some other arrangements made.
.Sh AUTHOR
.Nm Crunch
was written by James da Silva <jds@cs.umd.edu>.
.sp 0
Copyright (c) 1994 University of Maryland. All Rights Reserved.
|