balscm_version.h

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/// @file balscm_version.h
///
/// The content of this file has been pre-processed for Doxygen.
///
 
 
// balscm_version.h                                                   -*-C++-*-
#ifndef INCLUDED_BALSCM_VERSION
#define INCLUDED_BALSCM_VERSION
 
#include <bsls_ident.h>
BSLS_IDENT("$Id: $")
 
/// @defgroup balscm_version balscm_version
/// @brief  Provide source control management (versioning) information.
/// @addtogroup bal
/// @{
/// @addtogroup balscm
/// @{
/// @addtogroup balscm_version
/// @{
///
/// <h1> Outline </h1>
/// * <a href="#balscm_version-purpose"> Purpose</a>
/// * <a href="#balscm_version-classes"> Classes </a>
/// * <a href="#balscm_version-description"> Description </a>
///   * <a href="#balscm_version-usage"> Usage </a>
///     * <a href="#balscm_version-example-1-embedding-version-information"> Example 1: Embedding Version Information </a>
///     * <a href="#balscm_version-example-2-accessing-the-embedded-version-information"> Example 2: Accessing the Embedded Version information </a>
///
/// # Purpose {#balscm_version-purpose}
/// Provide source control management (versioning) information.
///
/// # Classes {#balscm_version-classes}
///
/// -  balscm::Version: namespace for versioning information for `bal`
///
/// # Description {#balscm_version-description}
/// This component provides source control management (versioning)
/// information for the `bal` package group.  In particular, this component
/// embeds RCS-style and SCCS-style version strings in binary executable files
/// that use one or more components from the `bal` package group.  This version
/// information may be extracted from binary files using common UNIX utilities
/// (e.g., `ident` and `what`).  In addition, the `version` `static` member
/// function in the `balscm::Version` struct can be used to query version
/// information for the `bal` package group at runtime.  The following {Usage}
/// examples illustrate these two basic capabilities.
///
/// Note that unless the `version` method will be called, it is not necessary to
/// "#include" this component header file to get `bal` version information
/// embedded in an executable.  It is only necessary to use one or more `bal`
/// components (and, hence, link in the `bal` library).
///
/// ## Usage {#balscm_version-usage}
///
///
/// This section illustrates intended use of this component.
///
/// ### Example 1: Embedding Version Information {#balscm_version-example-1-embedding-version-information}
///
///
/// The version of the `bal` package group linked into a program can be
/// obtained at runtime using the `version` `static` member function as follows:
/// @code
///       #include <balscm_version.h>
///
///       assert(0 != balscm::Version::version());
///
///       bsl::cout << "BAL version: " << balscm::Version::version()
///                 << bsl::endl;
/// @endcode
/// Output similar to the following will be printed to `stdout`:
/// @code
///       BAL version: BLP_LIB_BDE_BAL_0.01.0
/// @endcode
/// The "0.01.0" portion of the string distinguishes different versions of the
/// `bal` package group.
///
/// ### Example 2: Accessing the Embedded Version information {#balscm_version-example-2-accessing-the-embedded-version-information}
///
///
/// The versioning information embedded into a binary file by this component can
/// be examined under UNIX using several well-known utilities.  For example:
/// @code
///       $ ident a.out
///       a.out:
///            $Id: BLP_LIB_BDE_BAL_0.01.0 $
///
///       $ what a.out | grep BAL
///               BLP_LIB_BDE_BAL_0.01.0
///
///       $ strings a.out | grep BAL
///       $Id: BLP_LIB_BDE_BAL_0.01.0 $
///       @(#)BLP_LIB_BDE_BAL_0.01.0
///       BLP_LIB_BDE_BAL_0.01.0
/// @endcode
/// Note that `ident` and `what` typically will display many version strings
/// unrelated to `bal` depending on the libraries used by `a.out`.
/// @}
/** @} */
/** @} */
 
/** @addtogroup bal
 * @{
 */
/** @addtogroup balscm
 * @{
 */
/** @addtogroup balscm_version
 * @{
 */
 
#include <balscm_versiontag.h>     // 'BAL_VERSION_MAJOR', 'BAL_VERSION_MINOR'
 
#include <bslscm_version.h>
 
#include <bsls_linkcoercion.h>
 
 
 
namespace balscm {
 
                         // ==============
                         // struct Version
                         // ==============
 
/// This struct provides a namespace for (1) source control management
/// (versioning) information that is embedded in binary executable files,
/// and (2) a facility to query that information at runtime.
///
/// See @ref balscm_version 
struct Version {
 
    // CLASS DATA
    static const char *s_ident;              // RCS-style version string
    static const char *s_what;               // SCCS-style version string
 
#define BALSCM_CONCAT2(a,b,c,d,e,f) a ## b ## c ## d ## e ## f
#define BALSCM_CONCAT(a,b,c,d,e,f)  BALSCM_CONCAT2(a,b,c,d,e,f)
 
// 'BALSCM_S_VERSION' is a symbol whose name warns users of version mismatch
// linking errors.  Note that the exact string "compiled_this_object" must be
// present in this version coercion symbol.  Tools may look for this pattern to
// warn users of mismatches.
#define BALSCM_S_VERSION BALSCM_CONCAT(s_version_BAL_,       \
                                       BAL_VERSION_MAJOR, _, \
                                       BAL_VERSION_MINOR, _, \
                                       compiled_this_object)
 
    static const char *BALSCM_S_VERSION;     // BDE-style version string
 
    static const char *s_dependencies;       // available for future use
    static const char *s_buildInfo;          // available for future use
    static const char *s_timestamp;          // available for future use
    static const char *s_sourceControlInfo;  // available for future use
 
    // CLASS METHODS
 
    /// Return the address of a character string that identifies the version
    /// of the `bal` package group in use.
    static const char *version();
};
 
// ============================================================================
//                            INLINE DEFINITIONS
// ============================================================================
 
                         // --------------
                         // struct Version
                         // --------------
 
// CLASS METHODS
inline
const char *Version::version()
{
    return BALSCM_S_VERSION;
}
 
}  // close package namespace
 
// Force linker to pull in this component's object file.
 
BSLS_LINKCOERCION_FORCE_SYMBOL_DEPENDENCY(const char *,
                                          balscm_version_assertion,
                                          balscm::Version::BALSCM_S_VERSION)
 
 
 
#endif
 
// ----------------------------------------------------------------------------
// Copyright 2015 Bloomberg Finance L.P.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// ----------------------------- END-OF-FILE ----------------------------------
 
/** @} */
/** @} */
/** @} */