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![]() Plumb "struct key_value_info" through all code paths that end in die_bad_number(), which lets us remove the helper functions that read analogous values from "struct config_reader". As a result, nothing reads config_reader.config_kvi any more, so remove that too. In config.c, this requires changing the signature of git_configset_get_value() to 'return' "kvi" in an out parameter so that git_configset_get_<type>() can pass it to git_config_<type>(). Only numeric types will use "kvi", so for non-numeric types (e.g. git_configset_get_string()), pass NULL to indicate that the out parameter isn't needed. Outside of config.c, config callbacks now need to pass "ctx->kvi" to any of the git_config_<type>() functions that parse a config string into a number type. Included is a .cocci patch to make that refactor. The only exceptional case is builtin/config.c, where git_config_<type>() is called outside of a config callback (namely, on user-provided input), so config source information has never been available. In this case, die_bad_number() defaults to a generic, but perfectly descriptive message. Let's provide a safe, non-NULL for "kvi" anyway, but make sure not to change the message. Signed-off-by: Glen Choo <chooglen@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com> |
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tests | ||
.gitignore | ||
array.cocci | ||
commit.cocci | ||
config_fn_ctx.pending.cocci | ||
equals-null.cocci | ||
flex_alloc.cocci | ||
free.cocci | ||
git_config_number.cocci | ||
hashmap.cocci | ||
index-compatibility.cocci | ||
object_id.cocci | ||
preincr.cocci | ||
qsort.cocci | ||
README | ||
spatchcache | ||
strbuf.cocci | ||
swap.cocci | ||
the_repository.cocci | ||
xcalloc.cocci | ||
xopen.cocci | ||
xstrdup_or_null.cocci |
= coccinelle This directory provides Coccinelle (http://coccinelle.lip6.fr/) semantic patches that might be useful to developers. == Types of semantic patches * Using the semantic transformation to check for bad patterns in the code; The target 'make coccicheck' is designed to check for these patterns and it is expected that any resulting patch indicates a regression. The patches resulting from 'make coccicheck' are small and infrequent, so once they are found, they can be sent to the mailing list as per usual. Example for introducing new patterns: 67947c34ae (convert "hashcmp() != 0" to "!hasheq()", 2018-08-28) b84c783882 (fsck: s/++i > 1/i++/, 2018-10-24) Example of fixes using this approach: 248f66ed8e (run-command: use strbuf_addstr() for adding a string to a strbuf, 2018-03-25) f919ffebed (Use MOVE_ARRAY, 2018-01-22) These types of semantic patches are usually part of testing, c.f. 0860a7641b (travis-ci: fail if Coccinelle static analysis found something to transform, 2018-07-23) * Using semantic transformations in large scale refactorings throughout the code base. When applying the semantic patch into a real patch, sending it to the mailing list in the usual way, such a patch would be expected to have a lot of textual and semantic conflicts as such large scale refactorings change function signatures that are used widely in the code base. A textual conflict would arise if surrounding code near any call of such function changes. A semantic conflict arises when other patch series in flight introduce calls to such functions. So to aid these large scale refactorings, semantic patches can be used. However we do not want to store them in the same place as the checks for bad patterns, as then automated builds would fail. That is why semantic patches 'contrib/coccinelle/*.pending.cocci' are ignored for checks, and can be applied using 'make coccicheck-pending'. This allows to expose plans of pending large scale refactorings without impacting the bad pattern checks. == Git-specific tips & things to know about how we run "spatch": * The "make coccicheck" will piggy-back on "COMPUTE_HEADER_DEPENDENCIES". If you've built a given object file the "coccicheck" target will consider its depednency to decide if it needs to re-run on the corresponding source file. This means that a "make coccicheck" will re-compile object files before running. This might be unexpected, but speeds up the run in the common case, as e.g. a change to "column.h" won't require all coccinelle rules to be re-run against "grep.c" (or another file that happens not to use "column.h"). To disable this behavior use the "SPATCH_USE_O_DEPENDENCIES=NoThanks" flag. * To speed up our rules the "make coccicheck" target will by default concatenate all of the *.cocci files here into an "ALL.cocci", and apply it to each source file. This makes the run faster, as we don't need to run each rule against each source file. See the Makefile for further discussion, this behavior can be disabled with "SPATCH_CONCAT_COCCI=". But since they're concatenated any <id> in the <rulname> (e.g. "@ my_name", v.s. anonymous "@@") needs to be unique across all our *.cocci files. You should only need to name rules if other rules depend on them (currently only one rule is named). * To speed up incremental runs even more use the "spatchcache" tool in this directory as your "SPATCH". It aimns to be a "ccache" for coccinelle, and piggy-backs on "COMPUTE_HEADER_DEPENDENCIES". It caches in Redis by default, see it source for a how-to. In one setup with a primed cache "make coccicheck" followed by a "make clean && make" takes around 10s to run, but 2m30s with the default of "SPATCH_CONCAT_COCCI=Y". With "SPATCH_CONCAT_COCCI=" the total runtime is around ~6m, sped up to ~1m with "spatchcache". Most of the 10s (or ~1m) being spent on re-running "spatch" on files we couldn't cache, as we didn't compile them (in contrib/* and compat/* mostly). The absolute times will differ for you, but the relative speedup from caching should be on that order. == Authoring and reviewing coccinelle changes * When a .cocci is made, both the Git changes and .cocci file should be reviewed. When reviewing such a change, do your best to understand the .cocci changes (e.g. by asking the author to explain the change) and be explicit about your understanding of the changes. This helps us decide whether input from coccinelle experts is needed or not. If you aren't sure of the cocci changes, indicate what changes you actively endorse and leave an Acked-by (instead of Reviewed-by). * Authors should consider that reviewers may not be coccinelle experts, thus the the .cocci changes may not be self-evident. A plain text description of the changes is strongly encouraged, especially when using more esoteric features of the language. * .cocci rules should target only the problem it is trying to solve; "collateral damage" is not allowed. Reviewers should look out and flag overly-broad rules. * Consider the cost-benefit ratio of .cocci changes. In particular, consider the effect on the runtime of "make coccicheck", and how often your .cocci check will catch something valuable. As a rule of thumb, rules that can bail early if a file doesn't have a particular token will have a small impact on runtime, and vice-versa. * .cocci files used for refactoring should be temporarily kept in-tree to aid the refactoring of out-of-tree code (e.g. in-flight topics). Periodically evaluate the cost-benefit ratio to determine when the file should be removed. For example, consider how many out-of-tree users are left and how much this slows down "make coccicheck".