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.
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.
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
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'.
RENAME[libfoo]=libbar
-That lines has "libfoo" get renamed to "libbar". While it makes no
+That line has "libfoo" 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.
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:
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 - function that produces build file lines to build a
+ 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.
+
+ 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", ... ]);
+ 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.
-
- 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