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-rw-r--r--lib/erl_interface/doc/src/ei.xml64
1 files changed, 62 insertions, 2 deletions
diff --git a/lib/erl_interface/doc/src/ei.xml b/lib/erl_interface/doc/src/ei.xml
index 539e16d837..117c787da6 100644
--- a/lib/erl_interface/doc/src/ei.xml
+++ b/lib/erl_interface/doc/src/ei.xml
@@ -82,6 +82,25 @@
function returns the size required (note that for strings an
extra byte is needed for the 0 string terminator).</p>
</description>
+ <section>
+ <title>DATA TYPES</title>
+
+ <taglist>
+ <tag><marker id="erlang_char_encoding"/>enum erlang_char_encoding</tag>
+ <item>
+ <p/>
+ <code type="none">
+enum erlang_char_encoding {
+ ERLANG_ASCII, ERLANG_LATIN1, ERLANG_UTF8
+};
+</code>
+ <p>The character encoding used for atoms. <c>ERLANG_ASCII</c> represents 7-bit ASCII.
+ Latin1 and UTF8 are different extensions of 7-bit ASCII. All 7-bit ASCII characters
+ are valid Latin1 and UTF8 characters. ASCII and Latin1 both represent each character
+ by one byte. A UTF8 character can consist of one to four bytes.</p>
+ </item>
+ </taglist>
+ </section>
<funcs>
<func>
<name><ret>void</ret><nametext>ei_set_compat_rel(release_number)</nametext></name>
@@ -225,12 +244,32 @@
<fsummary>Encode an atom</fsummary>
<desc>
<p>Encodes an atom in the binary format. The <c><![CDATA[p]]></c> parameter
- is the name of the atom. Only upto <c><![CDATA[MAXATOMLEN]]></c> bytes
+ is the name of the atom in latin1 encoding. Only upto <c>MAXATOMLEN-1</c> bytes
are encoded. The name should be zero-terminated, except for
the <c><![CDATA[ei_x_encode_atom_len()]]></c> function.</p>
</desc>
</func>
<func>
+ <name><ret>int</ret><nametext>ei_encode_atom_as(char *buf, int *index, const char *p, enum erlang_char_encoding from_enc, enum erlang_char_encoding to_enc)</nametext></name>
+ <name><ret>int</ret><nametext>ei_encode_atom_len_as(char *buf, int *index, const char *p, int len, enum erlang_char_encoding from_enc, enum erlang_char_encoding to_enc)</nametext></name>
+ <name><ret>int</ret><nametext>ei_x_encode_atom_as(ei_x_buff* x, const char *p, enum erlang_char_encoding from_enc, enum erlang_char_encoding to_enc)</nametext></name>
+ <name><ret>int</ret><nametext>ei_x_encode_atom_len_as(ei_x_buff* x, const char *p, int len, enum erlang_char_encoding from_enc, enum erlang_char_encoding to_enc)</nametext></name>
+ <fsummary>Encode an atom</fsummary>
+ <desc>
+ <p>Encodes an atom in the binary format with character encoding
+ <c><seealso marker="#erlang_char_encoding">to_enc</seealso></c> (latin1 or utf8).
+ The <c>p</c> parameter is the name of the atom with character encoding
+ <c><seealso marker="#erlang_char_encoding">from_enc</seealso></c> (ascii, latin1 or utf8).
+ The name must either be zero-terminated or a function variant with a <c>len</c>
+ parameter must be used.</p>
+ <p>The encoding will fail if <c>p</c> is not a valid string in encoding <c>from_enc</c>,
+ if the string is too long or if it can not be represented with character encoding <c>to_enc</c>.</p>
+ <p>These functions were introduced in R16 release of Erlang/OTP as part of a first step
+ to support UTF8 atoms. Atoms encoded with <c>ERLANG_UTF8</c>
+ can not be decoded by earlier releases than R16.</p>
+ </desc>
+ </func>
+ <func>
<name><ret>int</ret><nametext>ei_encode_binary(char *buf, int *index, const void *p, long len)</nametext></name>
<name><ret>int</ret><nametext>ei_x_encode_binary(ei_x_buff* x, const void *p, long len)</nametext></name>
<fsummary>Encode a binary</fsummary>
@@ -490,11 +529,32 @@ ei_x_encode_empty_list(&amp;x);
<fsummary>Decode an atom</fsummary>
<desc>
<p>This function decodes an atom from the binary format. The
- name of the atom is placed at <c><![CDATA[p]]></c>. There can be at most
+ null terminated name of the atom is placed at <c><![CDATA[p]]></c>. There can be at most
<c><![CDATA[MAXATOMLEN]]></c> bytes placed in the buffer.</p>
</desc>
</func>
<func>
+ <name><ret>int</ret><nametext>ei_decode_atom_as(const char *buf, int *index, char *p, int plen, enum erlang_char_encoding want, enum erlang_char_encoding* was, enum erlang_char_encoding* result)</nametext></name>
+ <fsummary>Decode an atom</fsummary>
+ <desc>
+ <p>This function decodes an atom from the binary format. The
+ null terminated name of the atom is placed in buffer at <c>p</c> of length
+ <c>plen</c> bytes.</p>
+ <p>The wanted string encoding is specified by <c><seealso marker="#erlang_char_encoding">
+ want</seealso></c>. The original encoding used in the
+ binary format (latin1 or utf8) can be obtained from <c>*was</c>. The actual encoding of the resulting string
+ (7-bit ascii, latin1 or utf8) can be obtained from <c>*result</c>. Both <c>was</c> and <c>result</c> can be <c>NULL</c>.
+
+ <c>*result</c> may differ from <c>want</c> if <c>want</c> is a bitwise-or'd combination like
+ <c>ERLANG_LATIN1|ERLANG_UTF8</c> or if <c>*result</c> turn out to be pure 7-bit ascii
+ (compatible with both latin1 and utf8).</p>
+ <p>This function fails if the atom is too long for the buffer
+ or if it can not be represented with encoding <c>want</c>.</p>
+ <p>This function was introduced in R16 release of Erlang/OTP as part of a first step
+ to support UTF8 atoms.</p>
+ </desc>
+ </func>
+ <func>
<name><ret>int</ret><nametext>ei_decode_binary(const char *buf, int *index, void *p, long *len)</nametext></name>
<fsummary>Decode a binary</fsummary>
<desc>