NAME

ERR_put_error, ERR_add_error_data, ERR_add_error_vdata — record an OpenSSL error

SYNOPSIS

#include <openssl/err.h> void
ERR_put_error(int lib, int func, int reason, const char *file, int line); void
ERR_add_error_data(int num, ...); void
ERR_add_error_vdata(int num, va_list arg);

DESCRIPTION

ERR_put_error() adds an error code to the thread's error queue. It signals that the error of reason code reason occurred in function func of library lib, in line number line of file. This function is usually called by a macro. ERR_add_error_data() associates the concatenation of its num string arguments with the error code added last. ERR_add_error_vdata() is similar except the argument is a va_list. Use of ERR_add_error_data() and ERR_add_error_vdata() is deprecated inside of LibreSSL in favour of ERR_asprintf_error_data(3). ERR_load_strings(3) can be used to register error strings so that the application can generate human-readable error messages for the error code. Each sub-library has a specific macro XXXerr(f, r) that is used to report errors. Its first argument is a function code XXX_F_*; the second argument is a reason code XXX_R_*. Function codes are derived from the function names whereas reason codes consist of textual error descriptions. For example, the function ssl23_read() reports a "handshake failure" as follows:

SSLerr(SSL_F_SSL23_READ, SSL_R_SSL_HANDSHAKE_FAILURE);

Function and reason codes should consist of upper case characters, numbers and underscores only. The error file generation script translates function codes into function names by looking in the header files for an appropriate function name. If none is found, it just uses the capitalized form such as "SSL23_READ" in the above example. The trailing section of a reason code (after the "_R_") is translated into lower case and underscores changed to spaces. Although a library will normally report errors using its own specific XXXerr() macro, another library's macro can be used. This is normally only done when a library wants to include ASN.1 code which must use the ASN1err() macro.

SEE ALSO

ERR(3), ERR_asprintf_error_data(3), ERR_load_strings(3)

HISTORY

ERR_put_error() first appeared in SSLeay 0.4.4. ERR_add_error_data() first appeared in SSLeay 0.9.0. Both functions have been available since OpenBSD 2.4. ERR_add_error_vdata() first appeared in OpenSSL 1.0.1 and has been available since OpenBSD 5.3.