Mercurial > hg
view mercurial/mpatch.h @ 39814:d059cb669632
wireprotov2: allow multiple fields to follow revision maps
The *data wire protocol commands emit a series of CBOR values.
Because revision/delta data may be large, their data is emitted
outside the map as a top-level bytestring value.
Before this commit, we'd emit a single optional bytestring
value after the revision descriptor map. This got the job done.
But it was limiting in that we could only send a single field.
And, it required the consumer to know that the presence of a
key in the map implied the existence of a following bytestring
value.
This commit changes the encoding strategy so top-level bytestring
values in the stream are explicitly denoted in a "fieldsfollowing"
key. This key contains an array defining what fields that follow
and the expected size of each field.
By defining things this way, we can easily send N bytestring
values without any ambiguity about their order. In addition,
clients only need to know how to parse ``fieldsfollowing`` to
know if extra values are present.
Because this breaks backwards compatibility, we've bumped the version
number of the wire protocol version 2 API endpoint.
Differential Revision: https://phab.mercurial-scm.org/D4620
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Thu, 20 Sep 2018 12:57:23 -0700 |
parents | 761355833867 |
children | d86908050375 |
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#ifndef _HG_MPATCH_H_ #define _HG_MPATCH_H_ #define MPATCH_ERR_NO_MEM -3 #define MPATCH_ERR_CANNOT_BE_DECODED -2 #define MPATCH_ERR_INVALID_PATCH -1 struct mpatch_frag { int start, end, len; const char *data; }; struct mpatch_flist { struct mpatch_frag *base, *head, *tail; }; int mpatch_decode(const char *bin, ssize_t len, struct mpatch_flist **res); ssize_t mpatch_calcsize(ssize_t len, struct mpatch_flist *l); void mpatch_lfree(struct mpatch_flist *a); int mpatch_apply(char *buf, const char *orig, ssize_t len, struct mpatch_flist *l); struct mpatch_flist * mpatch_fold(void *bins, struct mpatch_flist *(*get_next_item)(void *, ssize_t), ssize_t start, ssize_t end); #endif