10.8.6. Copy Table Contents

To use a copy table generated by the linker, you must know the contents of the copy table. This information is included in a run-time-support library header file, cpy_tbl.h, which contains a C source representation of the copy table data structure that is generated by the linker. The following example shows the copy table header file.

/*****************************************************************************/
/* cpy_tbl.h v#####                                                          */
/* Copyright (c) 2003 Texas Instruments Incorporated                         */
/*                                                                           */
/* Specification of copy table data structures which can be automatically    */
/* generated by the linker (using the table() operator in the LCF).          */
/*****************************************************************************/
#ifndef _CPY_TBL
#define _CPY_TBL

#ifdef __cplusplus
extern "C" namespace std {
#endif /* __cplusplus */

/*****************************************************************************/
/* Copy Record Data Structure                                                */
/*****************************************************************************/
typedef struct copy_record
{
    unsigned int load_addr;
    unsigned int run_addr;
    unsigned int size;
} COPY_RECORD;

/*****************************************************************************/
/* Copy Table Data Structure                                                 */
/*****************************************************************************/
typedef struct copy_table
{
    unsigned short rec_size;
    unsigned short num_recs;
    COPY_RECORD recs[1];
} COPY_TABLE;

/*****************************************************************************/
/* Prototype for general purpose copy routine.                               */
/*****************************************************************************/
extern void copy_in(COPY_TABLE *tp);

#ifdef __cplusplus
} /* extern "C" namespace std */

#ifndef _CPP_STYLE_HEADER
using std::COPY_RECORD;
using std::COPY_TABLE;
using std::copy_in;
#endif /* _CPP_STYLE_HEADER */
#endif /* __cplusplus */
#endif /* !_CPY_TBL */

For each object component that is marked for a copy, the linker creates a COPY_RECORD object for it. Each COPY_RECORD contains at least the following information for the object component:

• The load address

• The run address

• The size

The linker collects all COPY_RECORDs that are associated with the same copy table into a COPY_TABLE object. The COPY_TABLE object contains the size of a given COPY_RECORD, the number of COPY_RECORDs in the table, and the array of COPY_RECORDs in the table. For instance, in the BINIT example in Boot-Time Copy Tables, the .first and .extra output sections will each have their own COPY_RECORD entries in the BINIT copy table. The BINIT copy table will then look like this:

COPY_TABLE __binit__ = { 12, 2,
                         { <load address of .first>,
                           <run address of .first>,
                           <size of .first> },
                         { <load address of .extra>,
                           <run address of .extra>,
                           <size of .extra> } };