Configurations of OpenSSL target platforms
==========================================
-Target configurations are a collection of facts that we know about
+Configuration targets are a collection of facts that we know about
different platforms and their capabilities. We organise them in a
hash table, where each entry represent a specific target.
+Note that configuration target names must be unique across all config
+files. The Configure script does check that a config file doesn't
+have config targets that shadow config targets from other files.
+
In each table entry, the following keys are significant:
inherit_from => Other targets to inherit values from.
sys_id => System identity for systems where that
is difficult to determine automatically.
+ enable => Enable specific configuration features.
+ This MUST be an array of words.
+ disable => Disable specific configuration features.
+ This MUST be an array of words.
+ Note: if the same feature is both enabled
+ and disabled, disable wins.
+
+ as => The assembler command. This is not always
+ used (for example on Unix, where the C
+ compiler is used instead).
+ asflags => Default assembler command flags [4].
+ cpp => The C preprocessor command, normally not
+ given, as the build file defaults are
+ usually good enough.
+ cppflags => Default C preprocessor flags [4].
+ defines => As an alternative, macro definitions may be
+ given here instead of in `cppflags' [4].
+ If given here, they MUST be as an array of
+ the string such as "MACRO=value", or just
+ "MACRO" for definitions without value.
+ includes => As an alternative, inclusion directories
+ may be given here instead of in `cppflags'
+ [4]. If given here, the MUST be an array
+ of strings, one directory specification
+ each.
cc => The C compiler command, usually one of "cc",
"gcc" or "clang". This command is normally
also used to link object files and
also used when linking a program where at
least one of the object file is made from
C++ source.
- cflags => Flags that are used at all times when
- compiling C object files.
- cxxflags => Flags that are used at all times when
- compiling C++ object files. If unset, it
- gets the same value as cflags.
- defines => As an alternative, macro definitions may be
- present here instead of in `cflags'. If
- given here, they MUST be as an array of the
- string such as "MACRO=value", or just
- "MACRO" for definitions without value.
- shared_cflag => Extra compilation flags used when
- compiling for shared libraries, typically
- something like "-fPIC".
+ cflags => Defaults C compiler flags [4].
+ cxxflags => Default C++ compiler flags [4]. If unset,
+ it gets the same value as cflags.
(linking is a complex thing, see [3] below)
ld => Linker command, usually not defined
instead).
(NOTE: this is here for future use, it's
not implemented yet)
- lflags => Flags that are used when linking apps.
- shared_ldflag => Flags that are used when linking shared
- or dynamic libraries.
- plib_lflags => Extra linking flags to appear just before
- the libraries on the command line.
+ lflags => Default flags used when linking apps,
+ shared libraries or DSOs [4].
ex_libs => Extra libraries that are needed when
- linking.
+ linking shared libraries, DSOs or programs.
+ The value is also assigned to Libs.private
+ in $(libdir)/pkgconfig/libcrypto.pc.
+
+ shared_cppflags => Extra C preprocessor flags used when
+ processing C files for shared libraries.
+ shared_cflag => Extra C compiler flags used when compiling
+ for shared libraries, typically something
+ like "-fPIC".
+ shared_ldflag => Extra linking flags used when linking
+ shared libraries.
+ module_cppflags
+ module_cflags
+ module_ldflags => Has the same function as the corresponding
+ `shared_' attributes, but for building DSOs.
+ When unset, they get the same values as the
+ corresponding `shared_' attributes.
ar => The library archive command, the default is
"ar".
(NOTE: this is here for future use, it's
not implemented yet)
arflags => Flags to be used with the library archive
- command.
+ command. On Unix, this includes the
+ command letter, 'r' by default.
ranlib => The library archive indexing command, the
default is 'ranlib' it it exists.
'<unistd.h>'. This is very rarely needed.
shared_extension => File name extension used for shared
- libraries.
+ libraries.
obj_extension => File name extension used for object files.
On unix, this defaults to ".o" (NOTE: this
is here for future use, it's not
files. On unix, this defaults to "" (NOTE:
this is here for future use, it's not
implemented yet)
+ shlib_variant => A "variant" identifier inserted between the base
+ shared library name and the extension. On "unixy"
+ platforms (BSD, Linux, Solaris, MacOS/X, ...) this
+ supports installation of custom OpenSSL libraries
+ that don't conflict with other builds of OpenSSL
+ installed on the system. The variant identifier
+ becomes part of the SONAME of the library and also
+ any symbol versions (symbol versions are not used or
+ needed with MacOS/X). For example, on a system
+ where a default build would normally create the SSL
+ shared library as 'libssl.so -> libssl.so.1.1' with
+ the value of the symlink as the SONAME, a target
+ definition that sets 'shlib_variant => "-abc"' will
+ create 'libssl.so -> libssl-abc.so.1.1', again with
+ an SONAME equal to the value of the symlink. The
+ symbol versions associated with the variant library
+ would then be 'OPENSSL_ABC_<version>' rather than
+ the default 'OPENSSL_<version>'. The string inserted
+ into symbol versions is obtained by mapping all
+ letters in the "variant" identifier to upper case
+ and all non-alphanumeric characters to '_'.
thread_scheme => The type of threads is used on the
configured platform. Currently known
that use dlopen() et al but do not have
fcntl.h), "DL" (shl_load() et al), "WIN32"
and "VMS".
- perlasm_scheme => The perlasm method used to created the
+ perlasm_scheme => The perlasm method used to create the
assembler files used when compiling with
assembler implementations.
shared_target => The shared library building method used.
- This is a target found in Makefile.shared.
+ This serves multiple purposes:
+ - as index for targets found in shared_info.pl.
+ - as linker script generation selector.
+ To serve both purposes, the index for shared_info.pl
+ should end with '-shared', and this suffix will be
+ removed for use as a linker script generation
+ selector. Note that the latter is only used if
+ 'shared_defflag' is defined.
build_scheme => The scheme used to build up a Makefile.
In its simplest form, the value is a string
with the name of the build scheme.
export vars as
accessor functions.
- apps_extra_src => Extra source to build apps/openssl, as
- needed by the target.
+ apps_aux_src => Extra source to build apps/openssl and other
+ apps, as needed by the target and that can be
+ collected in a library.
+ apps_init_src => Init source to build apps/openssl and other
+ apps, as needed by the target. This code
+ cannot be placed in a library, as the rest
+ of the code isn't expected to link to it
+ explicitly.
cpuid_asm_src => assembler implementation of cpuid code as
well as OPENSSL_cleanse().
Default to mem_clr.c
of this file):
shared libraries:
- {ld} $(CFLAGS) {shared_ldflag} -shared -o libfoo.so \
- -Wl,--whole-archive libfoo.a -Wl,--no-whole-archive \
- {plib_lflags} -lcrypto {ex_libs}
+ {ld} $(CFLAGS) {lflags} {shared_ldflag} -o libfoo.so \
+ foo/something.o foo/somethingelse.o {ex_libs}
shared objects:
- {ld} $(CFLAGS) {shared_ldflag} -shared -o libeng.so \
- blah1.o blah2.o {plib_lflags} -lcrypto {ex_libs}
+ {ld} $(CFLAGS) {lflags} {module_ldflags} -o libeng.so \
+ blah1.o blah2.o -lcrypto {ex_libs}
applications:
{ld} $(CFLAGS) {lflags} -o app \
- app1.o utils.o {plib_lflags} -lssl -lcrypto {ex_libs}
+ app1.o utils.o -lssl -lcrypto {ex_libs}
+[4] There are variants of these attribute, prefixed with `lib_',
+ `dso_' or `bin_'. Those variants replace the unprefixed attribute
+ when building library, DSO or program modules specifically.
Historically, the target configurations came in form of a string with
values separated by colons. This use is deprecated. The string form
directory for the current build.info file and the corresponding build
directory, all relative to the top of the build tree.
-To begin with, things to be built are declared by setting specific
+'Configure' only knows inherently about the top build.info file. For
+any other directory that has one, further directories to look into
+must be indicated like this:
+
+ SUBDIRS=something someelse
+
+On to things to be built; they are declared by setting specific
variables:
PROGRAMS=foo bar
LIBS=libsomething
ENGINES=libeng
SCRIPTS=myhack
- EXTRA=file1 file2
Note that the files mentioned for PROGRAMS, LIBS and ENGINES *must* be
without extensions. The build file templates will figure them out.
to be located in the source tree while files given through DEPEND are
expected to be located in the build tree)
-It's also possible to depend on static libraries explicitely:
+It's also possible to depend on static libraries explicitly:
DEPEND[foo]=libsomething.a
DEPEND[libbar]=libsomethingelse.a
This should be rarely used, and care should be taken to make sure it's
only used when supported. For example, native Windows build doesn't
-support build static libraries and DLLs at the same time, so using
+support building static libraries and DLLs at the same time, so using
static libraries on Windows can only be done when configured
'no-shared'.
-For some libraries, we maintain files with public symbols and their
-slot in a transfer vector (important on some platforms). It can be
-declared like this:
-
- ORDINALS[libcrypto]=crypto
-
-The value is not the name of the file in question, but rather the
-argument to util/mkdef.pl that indicates which file to use.
-
-One some platforms, shared libraries come with a name that's different
-from their static counterpart. That's declared as follows:
-
- SHARED_NAME[libfoo]=cygfoo-{- $config{shlibver} -}
-
-The example is from Cygwin, which has a required naming convention.
-
-Sometimes, it makes sense to rename an output file, for example a
-library:
-
- RENAME[libfoo]=libbar
-
-That lines has "libfoo" get renamed to "libbar". While it makes no
-sense at all to just have a rename like that (why not just use
-"libbar" everywhere?), it does make sense when it can be used
-conditionally. See a little further below for an example.
-
In some cases, it's desirable to include some source files in the
shared form of a library only:
INCLUDE[foo]=include
+It's also possible to specify C macros that should be defined:
+
+ DEFINE[foo]=FOO BAR=1
+
In some cases, one might want to generate some source files from
others, that's done as follows:
GENERATE[bar.s]=asm/bar.S
The value of each GENERATE line is a command line or part of it.
-Configure places no rules on the command line, except the the first
-item muct be the generator file. It is, however, entirely up to the
+Configure places no rules on the command line, except that the first
+item must be the generator file. It is, however, entirely up to the
build file template to define exactly how those command lines should
be handled, how the output is captured and so on.
NOTE: GENERATE lines are limited to one command only per GENERATE.
-As a last resort, it's possible to have raw build file lines, between
-BEGINRAW and ENDRAW lines as follows:
-
- BEGINRAW[Makefile(unix)]
- haha.h: {- $builddir -}/Makefile
- echo "/* haha */" > haha.h
- ENDRAW[Makefile(unix)]
-
-The word within square brackets is the build_file configuration item
-or the build_file configuration item followed by the second word in the
-build_scheme configuration item for the configured target within
-parenthesis as shown above. For example, with the following relevant
-configuration items:
-
- build_file => "build.ninja"
- build_scheme => [ "unified", "unix" ]
-
-... these lines will be considered:
-
- BEGINRAW[build.ninja]
- build haha.h: echo "/* haha */" > haha.h
- ENDRAW[build.ninja]
-
- BEGINRAW[build.ninja(unix)]
- build hoho.h: echo "/* hoho */" > hoho.h
- ENDRAW[build.ninja(unix)]
-
-Should it be needed because the recipes within a RAW section might
-clash with those generated by Configure, it's possible to tell it
-not to generate them with the use of OVERRIDES, for example:
-
- SOURCE[libfoo]=foo.c bar.c
-
- OVERRIDES=bar.o
- BEGINRAW[Makefile(unix)]
- bar.o: bar.c
- $(CC) $(CFLAGS) -DSPECIAL -c -o $@ $<
- ENDRAW[Makefile(unix)]
-
-See the documentation further up for more information on configuration
-items.
-
Finally, you can have some simple conditional use of the build.info
information, looking like this:
SOURCE[libfoo]=...
ENDIF
-or:
-
- # VMS has a cultural standard where all libraries are prefixed.
- # For OpenSSL, the choice is 'ossl_'
- IF[{- $config{target} =~ /^vms/ -}]
- RENAME[libcrypto]=ossl_libcrypto
- RENAME[libssl]=ossl_libssl
- ENDIF
-
Build-file programming with the "unified" build system
======================================================
incs => [ "INCL/PATH", ... ]
intent => one of "lib", "dso", "bin" );
- 'obj' has the intended object file *without*
- extension, src2obj() is expected to add that.
+ 'obj' has the intended object file with '.o'
+ extension, src2obj() is expected to change it to
+ something more suitable for the platform.
'srcs' has the list of source files to build the
object file, with the first item being the source
file that directly corresponds to the object file.
'lib' has the intended library file name *without*
extension, obj2lib is expected to add that. 'objs'
- has the list of object files (also *without*
- extension) to build this library.
+ has the list of object files to build this library.
+
+ libobj2shlib - backward compatibility function that's used the
+ same way as obj2shlib (described next), and was
+ expected to build the shared library from the
+ corresponding static library when that was suitable.
+ NOTE: building a shared library from a static
+ library is now DEPRECATED, as they no longer share
+ object files. Attempting to do this will fail.
- libobj2shlib - function that produces build file lines to build a
+ obj2shlib - function that produces build file lines to build a
shareable object library file ("libfoo.so" in Unix
- terms) from the corresponding static library file
- or object files.
+ terms) from the corresponding object files.
called like this:
- libobj2shlib(shlib => "PATH/TO/shlibfile",
- lib => "PATH/TO/libfile",
- objs => [ "PATH/TO/objectfile", ... ],
- deps => [ "PATH/TO/otherlibfile", ... ],
- ordinals => [ "word", "/PATH/TO/ordfile" ]);
+ obj2shlib(shlib => "PATH/TO/shlibfile",
+ lib => "PATH/TO/libfile",
+ objs => [ "PATH/TO/objectfile", ... ],
+ deps => [ "PATH/TO/otherlibfile", ... ]);
- 'lib' has the intended library file name *without*
- extension, libobj2shlib is expected to add that.
+ 'lib' has the base (static) library ffile name
+ *without* extension. This is useful in case
+ supporting files are needed (such as import
+ libraries on Windows).
'shlib' has the corresponding shared library name
*without* extension. 'deps' has the list of other
libraries (also *without* extension) this library
needs to be linked with. 'objs' has the list of
- object files (also *without* extension) to build
- this library. 'ordinals' MAY be present, and when
- it is, its value is an array where the word is
- "crypto" or "ssl" and the file is one of the ordinal
- files util/libeay.num or util/ssleay.num in the
- source directory.
-
- This function has a choice; it can use the
- corresponding static library as input to make the
- shared library, or the list of object files.
+ object files to build this library.
obj2dso - function that produces build file lines to build a
dynamic shared object file from object files.
deps => [ "PATH/TO/otherlibfile",
... ]);
- This is almost the same as libobj2shlib, but the
+ This is almost the same as obj2shlib, but the
intent is to build a shareable library that can be
- loaded in runtime (a "plugin"...). The differences
- are subtle, one of the most visible ones is that the
- resulting shareable library is produced from object
- files only.
+ loaded in runtime (a "plugin"...).
obj2bin - function that produces build file lines to build an
executable file from object files.
'bin' has the intended executable file name
*without* extension, obj2bin is expected to add
- that. 'objs' has the list of object files (also
- *without* extension) to build this library. 'deps'
- has the list of library files (also *without*
- extension) that the programs needs to be linked
- with.
+ that. 'objs' has the list of object files to build
+ this library. 'deps' has the list of library files
+ (also *without* extension) that the programs needs
+ to be linked with.
in2script - function that produces build file lines to build a
script file from some input.
projects / openssl.git / blobdiff