remove unneded wbuf->fd = -1 There's no need to set the fd to -1 on ibufs created with imsg_create(3), and it was probably never needed.

convert to use imsg_get_fd() While here also fix a fd leak in got-read-pack. We were dup'ing imsg.fd without closing imsg.fd later; instead just use imsg_get_fd() to extract the file descriptor. Tested by falsifian and Kyle Ackerman, thanks! 'go ahead' stsp@

portable: add missing header checks Some code in compat/ has #defines which were not being checked for in configure.ac, which could have lead to compilation failures were those files to be included on systems which needed them. In doing so, we can now remove libmd and libcrypto as these are no longer needed.

add some helper functions to compute hashes This adds a set of functions to abstract over SHA1Init, SHA1Update, SHA1Final, their respective SHA256 variants and how to compare digests. Replace all the SHA1*() usage with the new APIs. It's a preparatory step for sha256 handling. ok stsp@

portable: rework SHA detection Simply the SHA detection by not predicating on libcrypto, but instead checking individual header files.

portable: remove sha1.h; found portably Remove sha1.h as this is found portably across systems.

provide functions to parse/serialize different hashes it abstracts over the hash type and ensures that object ids are zero'ed before their sha1 digest is written. Needed by the incoming sha256 support. ok stsp@

rename lib/sha1.c to lib/hash.c It will soon grow functions to deal with sha256 too. stsp@ agrees.

include sha2.h too where sha1.h is included In preparation for wide sha256 support; stsp@ agrees. Change done mechanically with find . -iname \*.[cy] -exec sam {} + X ,x/<sha1\.h>/i/\n#include <sha2.h>

fix "got fetch" hang against out-of-date remote repositories Do not assume that remote repositories will always have our objects. In Git protocol terms: Do not wait for an ACK from the server before sending the final "done" message. Otherwise servers might be waiting for more have-lines from us in order to find a common ancestor, which will never be sent by us. Problem reported by James Cook who also provided an initial test case ok op@

got: further fetch tweaks to prevent unintended fetches Implement stsp's suggestion to only fetch remote's HEAD if the symref refs/remote/*/HEAD exists, and its target no longer matches the remote HEAD. This ensures users tracking a project won't miss a change in HEAD, while also fixing the issue reported by naddy where HEAD was fetched by default even though a specific, potentially less active, branch is cloned, resulting in a repository with more commits than necessary. In addition, unless 'got fetch -b <branch>' is used, the remote HEAD branch will be fetched if branches are not set in got.conf and there is no work tree to ascertain a branch, or said branches are not found on the server. ok stsp@

backout got: always fetch remote HEAD except when -b is used As pointed out by naddy, this behaviour is not ideal when users want to limit their repository to a particular branch which will diverge from HEAD over time, such as -stable branches. See https://marc.gameoftrees.org/mail/1676388048.8632_0.html

got: always fetch remote HEAD except when -b is used Rather than only fetch HEAD when there are no branches set in got.conf and there is no branch to be inferred from a work tree, or said branches don't exist on the server, always fetch HEAD unless 'got fetch -b branch' is used. ok stsp@

make 'got fetch -b branch' error reporting more helpful The patch to got-fetch-pack.c was written by stsp with only minor tweaks by me. Regress updated to account for the change in reporting. stsp's original got-fetch-pack.c diff ok op jamsek ok stsp@

special case 'got fetch -b <branch>' to only fetch <branch> As discussed on irc, this drops the implicit remote HEAD fetch when -b is used. got.1 has been updated to make the new fetch behaviour clear. ok stsp@

got: use intermediate pointers to plug leak on realloc And save worktree_branch_len for reuse. ok stsp@ and op@

fix interaction of 'got fetch -b', got.conf, and work tree Without branches in got.conf for a remote, and without -b/-R options, the fallback to HEAD would only work when not invoked in a work tree. With this fix 'got fetch' should behave as described in the man page. The -b option now overrides both got.conf and the fallback to the work tree's branch. And fallback to HEAD works as expected when invoked in a repository. Also, do not strictly require remote repositories to provide a branch from the refs/heads/ namespace. In such cases users should be able to use -R to select something to fetch. ok jamsek

got_imsg_fetch_ref: use struct instead of buffer for id ok stsp@

got_imsg_fetch_have_ref: use struct instead of buffer for id ok stsp@

replace malloc+memcpy with strndup. no functional change intended ok stsp@

got: minor refactor of got_pathlist_free() API Accept flag parameter to optionally specify which pointers to free. This saves callers looping through the list to free pointers. ok + fix stsp@

fix uninitialised fildes variables in libexec helpers Reviewed and uncovered as part of the diff in the forthcoming commit (pathlist API refactor). ok stsp@

always cast ctype' is*() arguments to unsigned char ok stsp@

make 'got clone -b' work for repositories which lack a HEAD reference ok op@

avoid looping over SHA1Update() in got-fetch-pack; suggested by millert@