d2i_X509.pod: clarify usage of the 'pp' function parameter
The 'pp' function parameters of d2i_TYPE() and i2d_TYPE() are referenced
in the DESCRIPTION section as 'in' resp. 'out'. This commit renames the
references to 'ppin' resp. 'ppout' and adds an explaining sentence.
@@ -364,11 +364,11 @@ i2d_X509_VAL,
=for comment generic
- TYPE *d2i_TYPE(TYPE **a, unsigned char **pp, long length);
+ TYPE *d2i_TYPE(TYPE **a, unsigned char **ppin, long length);
TYPE *d2i_TYPE_bio(BIO *bp, TYPE **a);
TYPE *d2i_TYPE_fp(FILE *fp, TYPE **a);
- int i2d_TYPE(TYPE *a, unsigned char **pp);
+ int i2d_TYPE(TYPE *a, unsigned char **ppout);
int i2d_TYPE_fp(FILE *fp, TYPE *a);
int i2d_TYPE_bio(BIO *bp, TYPE *a);
@@ -376,14 +376,16 @@ i2d_X509_VAL,
In the description here, I<TYPE> is used a placeholder
for any of the OpenSSL datatypes, such as I<X509_CRL>.
+The function parameters I<ppin> and I<ppout> are generally
+either both named I<pp> in the headers, or I<in> and I<out>.
These functions convert OpenSSL objects to and from their ASN.1/DER
encoding. Unlike the C structures which can have pointers to sub-objects
within, the DER is a serialized encoding, suitable for sending over the
network, writing to a file, and so on.
-d2i_TYPE() attempts to decode B<len> bytes at B<*in>. If successful a
-pointer to the B<TYPE> structure is returned and B<*in> is incremented to
+d2i_TYPE() attempts to decode B<len> bytes at B<*ppin>. If successful a
+pointer to the B<TYPE> structure is returned and B<*ppin> is incremented to
the byte following the parsed data. If B<a> is not B<NULL> then a pointer
to the returned structure is also written to B<*a>. If an error occurred
then B<NULL> is returned.
@@ -401,13 +403,13 @@ d2i_TYPE_fp() is similar to d2i_TYPE() except it attempts
to parse data from FILE pointer B<fp>.
i2d_TYPE() encodes the structure pointed to by B<a> into DER format.
-If B<out> is not B<NULL>, it writes the DER encoded data to the buffer
-at B<*out>, and increments it to point after the data just written.
+If B<ppout> is not B<NULL>, it writes the DER encoded data to the buffer
+at B<*ppout>, and increments it to point after the data just written.
If the return value is negative an error occurred, otherwise it
returns the length of the encoded data.
-If B<*out> is B<NULL> memory will be allocated for a buffer and the encoded
-data written to it. In this case B<*out> is not incremented and it points
+If B<*ppout> is B<NULL> memory will be allocated for a buffer and the encoded
+data written to it. In this case B<*ppout> is not incremented and it points
to the start of the data just written.
i2d_TYPE_bio() is similar to i2d_TYPE() except it writes
@@ -438,7 +440,7 @@ Therefore any FILE pointers or BIOs should be opened in binary mode.
Functions such as strlen() will B<not> return the correct length
of the encoded structure.
-The ways that B<*in> and B<*out> are incremented after the operation
+The ways that B<*ppin> and B<*ppout> are incremented after the operation
can trap the unwary. See the B<WARNINGS> section for some common
errors.
The reason for this-auto increment behaviour is to reflect a typical
