Do not add 'filehash' var to manifest if filesize=0
Do not accept 'filehash' var when parsing manifest with filesize=0
When responding to a new rhizome advertisement, do not try to HTTP
request a payload if filesize=0, just import the manifest directly
Various operations, eg "rhizome file add", do not report 'filehash'
fields where 'filesize' is zero
Do not delete rows from MANIFESTS table which have empty filehash
Various related bug fixes
Handle manifests with empty payloads:
- assert_manifest_complete() asserts for a filehash field if the
filesize is non zero, otherwise asserts for NO filehash field
- assert_stdout_add_file() ditto
- unpack_manifest_for_grep() allows an empty name if payload also empty
create_rhizome_identities() sets SID and SID{I} vars
assert_rhizome_list() dumps stderr if any assert fails
Remove need to nul-terminate the received buffers in HTTP fetch reply handling
and HTTP server request parsing.
Remove redundant copying of data.
More rigorous parsing code, probably less vulnerable to overrun exploits.
Better debug logging of requests and responses.
Rhizome manifest parser now parses and validates all known fields, informs
about unsupported fields, and unpacks fields into relevant struct manifest
elements where appropriate. Is also stricter about whitespace.
Rhizome fetch code now logs debug messages if DEBUG_RHIZOME_RX bit is on.
Was not transmitting actual HTTP server port in rhizome announcements, was
always transmitting port 4110.
When trying for a free HTTP server port, sometimes bind() succeeds but listen()
fails with EADDRINUSE, so new logic to deal with that.
Now write_str(), write_nonblock(), write_all(), set_nonblock() etc. report the
file/line/function of their caller, rather than the function in net.c. Done
using macros, similar in style to WHY() etc.
SET_NONBLOCKING(), SET_BLOCKING(), WRITE_STR() are now set_nonblock(),
set_block() and write_str() respectively, all of which log an error before
returning -1. There are other useful methods: write_all() treats anything less
than all bytes written as an error; write_nonblock() treats EAGAIN and EINTR as
zero bytes written, and a combination: write_all_nonblock().
