CONTRIBUTING: remove redundant information, add additional information. [skip ci]

Remove a paragraph left over from the process of editing.

Indicate what the individual ND_TCHECK_*() macros do, and indicate that
*n*, in the GET_*_n() macros, is the length of the item to be fetched,
in bytes.

(cherry picked from commit 9ab359ed5eb2d424df931b3eaaba902cd79f23c6)

diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 22f029cdf7a520e5f65cfec336c9d7d63d801611..faa0f13d519f2856607ed58839672909228ef481 100644 (file)
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -129,12 +129,6 @@ and ask!
    This means that an attempt to fetch packet data based on the expected
    format of the packet may run the risk of overrunning the buffer.
 
    This means that an attempt to fetch packet data based on the expected
    format of the packet may run the risk of overrunning the buffer.
 

-   This is because the printer may receive incomplete packet in the
-   buffer, truncated at any random position, for example by capturing
-   with `-s size` option, so any attempt to fetch packet data based on
-   the expected format of the packet may run the risk of overrunning the
-   buffer.
-

    Furthermore, if the packet is complete, but is not correctly formed,
    that can also cause a printer to overrun the buffer, as it will be
    fetching packet data based on the expected format of the packet.
    Furthermore, if the packet is complete, but is not correctly formed,
    that can also cause a printer to overrun the buffer, as it will be
    fetching packet data based on the expected format of the packet.


@@ -154,6 +148,13 @@ and ask!
    ND_TCHECK_SIZE(p)
    ND_TCHECK_LEN(p, l)
    ```
    ND_TCHECK_SIZE(p)
    ND_TCHECK_LEN(p, l)
    ```

+
+   where *p* points to the data not being decoded.  For `ND_CHECK_n()`,
+   *n* is the length of the gap, in bytes.  For `ND_CHECK_SIZE()`, the
+   length of the gap, in bytes, is the size of an item of the data type
+   to which *p* points.  For `ND_CHECK_LEN()`, *l* is the length of the
+   gap, in bytes.
+

    For the `GET_*()` and `ND_TCHECK_*` macros (if not already done):
    * Assign: `ndo->ndo_protocol = "protocol";`
    * Define: `ND_LONGJMP_FROM_TCHECK` before including `netdissect.h`
    For the `GET_*()` and `ND_TCHECK_*` macros (if not already done):
    * Assign: `ndo->ndo_protocol = "protocol";`
    * Define: `ND_LONGJMP_FROM_TCHECK` before including `netdissect.h`


@@ -183,7 +184,8 @@ and ask!
    `U` indicates that an unsigned value is fetched; `S` indicates that a
    signed value is fetched.  For multi-byte values, `BE` indicates that
    a big-endian value ("network byte order") is fetched, and `LE`
    `U` indicates that an unsigned value is fetched; `S` indicates that a
    signed value is fetched.  For multi-byte values, `BE` indicates that
    a big-endian value ("network byte order") is fetched, and `LE`

-   indicates that a little-endian value is fetched.
+   indicates that a little-endian value is fetched. *n* is the length,
+   in bytes, of the multi-byte integral value to be fetched.

 
    In addition to the bounds checking the `GET_*()` macros perform,
    using those macros has other advantages:
 
    In addition to the bounds checking the `GET_*()` macros perform,
    using those macros has other advantages: