openssl/crypto/err
Richard Levitte fcd2d5a612 Refactor the computation of API version limits
Previously, the API version limit was indicated with a numeric version
number.  This was "natural" in the pre-3.0.0 because the version was
this simple number.

With 3.0.0, the version is divided into three separate numbers, and
it's only the major number that counts, but we still need to be able
to support pre-3.0.0 version limits.

Therefore, we allow OPENSSL_API_COMPAT to be defined with a pre-3.0.0
style numeric version number or with a simple major number, i.e. can
be defined like this for any application:

    -D OPENSSL_API_COMPAT=0x10100000L
    -D OPENSSL_API_COMPAT=3

Since the pre-3.0.0 numerical version numbers are high, it's easy to
distinguish between a simple major number and a pre-3.0.0 numerical
version number and to thereby support both forms at the same time.

Internally, we define the following macros depending on the value of
OPENSSL_API_COMPAT:

    OPENSSL_API_0_9_8
    OPENSSL_API_1_0_0
    OPENSSL_API_1_1_0
    OPENSSL_API_3

They indicate that functions marked for deprecation in the
corresponding major release shall not be built if defined.

Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/7724)
2018-12-06 12:24:48 +01:00
..
build.info unified build scheme: add build.info files 2016-02-01 12:46:58 +01:00
err.c Refactor the computation of API version limits 2018-12-06 12:24:48 +01:00
err_all.c Update copyright year 2018-02-13 13:59:25 +00:00
err_prn.c Consistent formatting for sizeof(foo) 2017-12-07 19:11:49 -05:00
openssl.ec Fix some TLSv1.3 alert issues 2018-07-31 09:31:50 +01:00
openssl.txt KMAC implementation using EVP_MAC 2018-11-14 07:01:09 +10:00
README Clean up "generic" intro pod files. 2016-06-09 16:39:19 -04:00

Adding new libraries
--------------------

When adding a new sub-library to OpenSSL, assign it a library number
ERR_LIB_XXX, define a macro XXXerr() (both in err.h), add its
name to ERR_str_libraries[] (in crypto/err/err.c), and add
ERR_load_XXX_strings() to the ERR_load_crypto_strings() function
(in crypto/err/err_all.c). Finally, add an entry:

    L      XXX     xxx.h   xxx_err.c

to crypto/err/openssl.ec, and add xxx_err.c to the Makefile.
Running make errors will then generate a file xxx_err.c, and
add all error codes used in the library to xxx.h.

Additionally the library include file must have a certain form.
Typically it will initially look like this:

    #ifndef HEADER_XXX_H
    #define HEADER_XXX_H

    #ifdef __cplusplus
    extern "C" {
    #endif

    /* Include files */

    #include <openssl/bio.h>
    #include <openssl/x509.h>

    /* Macros, structures and function prototypes */


    /* BEGIN ERROR CODES */

The BEGIN ERROR CODES sequence is used by the error code
generation script as the point to place new error codes, any text
after this point will be overwritten when make errors is run.
The closing #endif etc will be automatically added by the script.

The generated C error code file xxx_err.c will load the header
files stdio.h, openssl/err.h and openssl/xxx.h so the
header file must load any additional header files containing any
definitions it uses.