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- <a name="Internal"></a>
- <div class="header">
- <p>
- Next: <a href="File-Caching.html#File-Caching" accesskey="n" rel="next">File Caching</a>, Previous: <a href="Opening-and-Closing.html#Opening-and-Closing" accesskey="p" rel="prev">Opening and Closing</a>, Up: <a href="BFD-front-end.html#BFD-front-end" accesskey="u" rel="up">BFD front end</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="BFD-Index.html#BFD-Index" title="Index" rel="index">Index</a>]</p>
- </div>
- <hr>
- <a name="Implementation-details"></a>
- <h3 class="section">2.15 Implementation details</h3>
-
-
- <a name="Internal-functions"></a>
- <h4 class="subsection">2.15.1 Internal functions</h4>
-
-
- <p><strong>Description</strong><br>
- These routines are used within BFD.
- They are not intended for export, but are documented here for
- completeness.
- </p>
- <a name="index-bfd_005fwrite_005fbigendian_005f4byte_005fint"></a>
- <a name="bfd_005fwrite_005fbigendian_005f4byte_005fint"></a>
- <h4 class="subsubsection">2.15.1.1 <code>bfd_write_bigendian_4byte_int</code></h4>
- <p><strong>Synopsis</strong>
- </p><div class="example">
- <pre class="example">bfd_boolean bfd_write_bigendian_4byte_int (bfd *, unsigned int);
- </pre></div>
- <p><strong>Description</strong><br>
- Write a 4 byte integer <var>i</var> to the output BFD <var>abfd</var>, in big
- endian order regardless of what else is going on. This is useful in
- archives.
- </p>
- <a name="index-bfd_005fput_005fsize"></a>
- <a name="bfd_005fput_005fsize"></a>
- <h4 class="subsubsection">2.15.1.2 <code>bfd_put_size</code></h4>
- <a name="index-bfd_005fget_005fsize-1"></a>
- <a name="bfd_005fget_005fsize-1"></a>
- <h4 class="subsubsection">2.15.1.3 <code>bfd_get_size</code></h4>
- <p><strong>Description</strong><br>
- These macros as used for reading and writing raw data in
- sections; each access (except for bytes) is vectored through
- the target format of the BFD and mangled accordingly. The
- mangling performs any necessary endian translations and
- removes alignment restrictions. Note that types accepted and
- returned by these macros are identical so they can be swapped
- around in macros—for example, <samp>libaout.h</samp> defines <code>GET_WORD</code>
- to either <code>bfd_get_32</code> or <code>bfd_get_64</code>.
- </p>
- <p>In the put routines, <var>val</var> must be a <code>bfd_vma</code>. If we are on a
- system without prototypes, the caller is responsible for making
- sure that is true, with a cast if necessary. We don’t cast
- them in the macro definitions because that would prevent <code>lint</code>
- or <code>gcc -Wall</code> from detecting sins such as passing a pointer.
- To detect calling these with less than a <code>bfd_vma</code>, use
- <code>gcc -Wconversion</code> on a host with 64 bit <code>bfd_vma</code>’s.
- </p><div class="example">
- <pre class="example">
-
- /* Byte swapping macros for user section data. */
-
- #define bfd_put_8(abfd, val, ptr) \
- ((void) (*((unsigned char *) (ptr)) = (val) & 0xff))
- #define bfd_put_signed_8 \
- bfd_put_8
- #define bfd_get_8(abfd, ptr) \
- ((bfd_vma) *(const unsigned char *) (ptr) & 0xff)
- #define bfd_get_signed_8(abfd, ptr) \
- ((((bfd_signed_vma) *(const unsigned char *) (ptr) & 0xff) ^ 0x80) - 0x80)
-
- #define bfd_put_16(abfd, val, ptr) \
- BFD_SEND (abfd, bfd_putx16, ((val),(ptr)))
- #define bfd_put_signed_16 \
- bfd_put_16
- #define bfd_get_16(abfd, ptr) \
- BFD_SEND (abfd, bfd_getx16, (ptr))
- #define bfd_get_signed_16(abfd, ptr) \
- BFD_SEND (abfd, bfd_getx_signed_16, (ptr))
-
- #define bfd_put_24(abfd, val, ptr) \
- do \
- if (bfd_big_endian (abfd)) \
- bfd_putb24 ((val), (ptr)); \
- else \
- bfd_putl24 ((val), (ptr)); \
- while (0)
-
- bfd_vma bfd_getb24 (const void *p);
- bfd_vma bfd_getl24 (const void *p);
-
- #define bfd_get_24(abfd, ptr) \
- (bfd_big_endian (abfd) ? bfd_getb24 (ptr) : bfd_getl24 (ptr))
-
- #define bfd_put_32(abfd, val, ptr) \
- BFD_SEND (abfd, bfd_putx32, ((val),(ptr)))
- #define bfd_put_signed_32 \
- bfd_put_32
- #define bfd_get_32(abfd, ptr) \
- BFD_SEND (abfd, bfd_getx32, (ptr))
- #define bfd_get_signed_32(abfd, ptr) \
- BFD_SEND (abfd, bfd_getx_signed_32, (ptr))
-
- #define bfd_put_64(abfd, val, ptr) \
- BFD_SEND (abfd, bfd_putx64, ((val), (ptr)))
- #define bfd_put_signed_64 \
- bfd_put_64
- #define bfd_get_64(abfd, ptr) \
- BFD_SEND (abfd, bfd_getx64, (ptr))
- #define bfd_get_signed_64(abfd, ptr) \
- BFD_SEND (abfd, bfd_getx_signed_64, (ptr))
-
- #define bfd_get(bits, abfd, ptr) \
- ((bits) == 8 ? bfd_get_8 (abfd, ptr) \
- : (bits) == 16 ? bfd_get_16 (abfd, ptr) \
- : (bits) == 32 ? bfd_get_32 (abfd, ptr) \
- : (bits) == 64 ? bfd_get_64 (abfd, ptr) \
- : (abort (), (bfd_vma) - 1))
-
- #define bfd_put(bits, abfd, val, ptr) \
- ((bits) == 8 ? bfd_put_8 (abfd, val, ptr) \
- : (bits) == 16 ? bfd_put_16 (abfd, val, ptr) \
- : (bits) == 32 ? bfd_put_32 (abfd, val, ptr) \
- : (bits) == 64 ? bfd_put_64 (abfd, val, ptr) \
- : (abort (), (void) 0))
-
- </pre></div>
-
- <a name="index-bfd_005fh_005fput_005fsize"></a>
- <a name="bfd_005fh_005fput_005fsize"></a>
- <h4 class="subsubsection">2.15.1.4 <code>bfd_h_put_size</code></h4>
- <p><strong>Description</strong><br>
- These macros have the same function as their <code>bfd_get_x</code>
- brethren, except that they are used for removing information
- for the header records of object files. Believe it or not,
- some object files keep their header records in big endian
- order and their data in little endian order.
- </p><div class="example">
- <pre class="example">
-
- /* Byte swapping macros for file header data. */
-
- #define bfd_h_put_8(abfd, val, ptr) \
- bfd_put_8 (abfd, val, ptr)
- #define bfd_h_put_signed_8(abfd, val, ptr) \
- bfd_put_8 (abfd, val, ptr)
- #define bfd_h_get_8(abfd, ptr) \
- bfd_get_8 (abfd, ptr)
- #define bfd_h_get_signed_8(abfd, ptr) \
- bfd_get_signed_8 (abfd, ptr)
-
- #define bfd_h_put_16(abfd, val, ptr) \
- BFD_SEND (abfd, bfd_h_putx16, (val, ptr))
- #define bfd_h_put_signed_16 \
- bfd_h_put_16
- #define bfd_h_get_16(abfd, ptr) \
- BFD_SEND (abfd, bfd_h_getx16, (ptr))
- #define bfd_h_get_signed_16(abfd, ptr) \
- BFD_SEND (abfd, bfd_h_getx_signed_16, (ptr))
-
- #define bfd_h_put_32(abfd, val, ptr) \
- BFD_SEND (abfd, bfd_h_putx32, (val, ptr))
- #define bfd_h_put_signed_32 \
- bfd_h_put_32
- #define bfd_h_get_32(abfd, ptr) \
- BFD_SEND (abfd, bfd_h_getx32, (ptr))
- #define bfd_h_get_signed_32(abfd, ptr) \
- BFD_SEND (abfd, bfd_h_getx_signed_32, (ptr))
-
- #define bfd_h_put_64(abfd, val, ptr) \
- BFD_SEND (abfd, bfd_h_putx64, (val, ptr))
- #define bfd_h_put_signed_64 \
- bfd_h_put_64
- #define bfd_h_get_64(abfd, ptr) \
- BFD_SEND (abfd, bfd_h_getx64, (ptr))
- #define bfd_h_get_signed_64(abfd, ptr) \
- BFD_SEND (abfd, bfd_h_getx_signed_64, (ptr))
-
- /* Aliases for the above, which should eventually go away. */
-
- #define H_PUT_64 bfd_h_put_64
- #define H_PUT_32 bfd_h_put_32
- #define H_PUT_16 bfd_h_put_16
- #define H_PUT_8 bfd_h_put_8
- #define H_PUT_S64 bfd_h_put_signed_64
- #define H_PUT_S32 bfd_h_put_signed_32
- #define H_PUT_S16 bfd_h_put_signed_16
- #define H_PUT_S8 bfd_h_put_signed_8
- #define H_GET_64 bfd_h_get_64
- #define H_GET_32 bfd_h_get_32
- #define H_GET_16 bfd_h_get_16
- #define H_GET_8 bfd_h_get_8
- #define H_GET_S64 bfd_h_get_signed_64
- #define H_GET_S32 bfd_h_get_signed_32
- #define H_GET_S16 bfd_h_get_signed_16
- #define H_GET_S8 bfd_h_get_signed_8
-
-
- </pre></div>
-
- <a name="index-bfd_005flog2"></a>
- <a name="bfd_005flog2"></a>
- <h4 class="subsubsection">2.15.1.5 <code>bfd_log2</code></h4>
- <p><strong>Synopsis</strong>
- </p><div class="example">
- <pre class="example">unsigned int bfd_log2 (bfd_vma x);
- </pre></div>
- <p><strong>Description</strong><br>
- Return the log base 2 of the value supplied, rounded up. E.g., an
- <var>x</var> of 1025 returns 11. A <var>x</var> of 0 returns 0.
- </p>
-
- <hr>
- <div class="header">
- <p>
- Next: <a href="File-Caching.html#File-Caching" accesskey="n" rel="next">File Caching</a>, Previous: <a href="Opening-and-Closing.html#Opening-and-Closing" accesskey="p" rel="prev">Opening and Closing</a>, Up: <a href="BFD-front-end.html#BFD-front-end" accesskey="u" rel="up">BFD front end</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="BFD-Index.html#BFD-Index" title="Index" rel="index">Index</a>]</p>
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