| Message ID | 20201222000220.1491091-4-emilyshaffer@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | propose config-based hooks (part I) | expand |
> Teach 'git hook list <hookname>', which checks the known configs in > order to create an ordered list of hooks to run on a given hook event. > > Multiple commands can be specified for a given hook by providing > multiple "hook.<hookname>.command = <path-to-hook>" lines. Hooks will be > run in config order. If more properties need to be set on a given hook > in the future, commands can also be specified by providing > "hook.<hookname>.command = <hookcmd-name>", as well as a "[hookcmd > <hookcmd-name>]" subsection; at minimum, this subsection must contain a > "hookcmd.<hookcmd-name>.command = <path-to-hook>" line. I learned later that this isn't true - in patch 6, the commit message and one of the tests therein describe being able to skip a previously inline command by making a hookcmd section of the same name and just specifying "skip = true" there (without any command). Maybe just delete the "at minimum" part. > +static int list(int argc, const char **argv, const char *prefix) > { > - struct option builtin_hook_options[] = { > + struct list_head *head, *pos; > + struct hook *item; You asked for review on nits too so here's one: "item" should be declared in the list_for_each block. (That also makes it easier to see that we don't need to free it.) > diff --git a/hook.c b/hook.c > new file mode 100644 > index 0000000000..937dc768c8 > --- /dev/null > +++ b/hook.c > @@ -0,0 +1,115 @@ > +#include "cache.h" > + > +#include "hook.h" > +#include "config.h" Usually we put all the includes together without any intervening blank lines. > +static void append_or_move_hook(struct list_head *head, const char *command) > +{ > + struct list_head *pos = NULL, *tmp = NULL; > + struct hook *to_add = NULL; > + > + /* > + * remove the prior entry with this command; we'll replace it at the > + * end. > + */ > + list_for_each_safe(pos, tmp, head) { > + struct hook *it = list_entry(pos, struct hook, list); > + if (!strcmp(it->command.buf, command)) { > + list_del(pos); > + /* we'll simply move the hook to the end */ > + to_add = it; "break" here? > + } > + } > + > + if (!to_add) { > + /* adding a new hook, not moving an old one */ > + to_add = xmalloc(sizeof(struct hook)); Style is to write sizeof(*to_add), I think. [snip] > +struct hook_config_cb > +{ > + struct strbuf *hookname; struct declarations have "{" not on a line on its own. Also, "hookname" could just be a char *? > + struct list_head *list; > +}; > + > +static int hook_config_lookup(const char *key, const char *value, void *cb_data) > +{ > + struct hook_config_cb *data = cb_data; > + const char *hook_key = data->hookname->buf; > + struct list_head *head = data->list; > + > + if (!strcmp(key, hook_key)) { > + const char *command = value; > + struct strbuf hookcmd_name = STRBUF_INIT; > + > + /* Check if a hookcmd with that name exists. */ > + strbuf_addf(&hookcmd_name, "hookcmd.%s.command", command); > + git_config_get_value(hookcmd_name.buf, &command); So we don't really care whether git_config_get_value returns 0 or 1 as long as it doesn't touch "command" if there is no such hookcmd. That fits with how git_config_get_value() is documented, so that's great. Perhaps better to document as: If a hookcmd.%s.command config exists, replace the command with the value of that config. (If not, do nothing - git_config_get_value() is documented to not overwrite the value argument in this case.) > + > + if (!command) { > + strbuf_release(&hookcmd_name); > + BUG("git_config_get_value overwrote a string it shouldn't have"); > + } > + > + /* > + * TODO: implement an option-getting callback, e.g. > + * get configs by pattern hookcmd.$value.* > + * for each key+value, do_callback(key, value, cb_data) > + */ > + > + append_or_move_hook(head, command); > + > + strbuf_release(&hookcmd_name); > + } > + > + return 0; > +} > + > +struct list_head* hook_list(const struct strbuf* hookname) "const char *hookname" should suffice? Also, search for "* " and replace with " *" where applicable (also in the .h file). > +{ > + struct strbuf hook_key = STRBUF_INIT; > + struct list_head *hook_head = xmalloc(sizeof(struct list_head)); > + struct hook_config_cb cb_data = { &hook_key, hook_head }; > + > + INIT_LIST_HEAD(hook_head); > + > + if (!hookname) > + return NULL; > + > + strbuf_addf(&hook_key, "hook.%s.command", hookname->buf); > + > + git_config(hook_config_lookup, (void*)&cb_data); Do we need this void* cast? > + > + strbuf_release(&hook_key); > + return hook_head; > +} > diff --git a/hook.h b/hook.h > new file mode 100644 > index 0000000000..8ffc4f14b6 > --- /dev/null > +++ b/hook.h > @@ -0,0 +1,26 @@ > +#include "config.h" > +#include "list.h" > +#include "strbuf.h" > + > +struct hook > +{ > + struct list_head list; > + /* > + * Config file which holds the hook.*.command definition. > + * (This has nothing to do with the hookcmd.<name>.* configs.) > + */ > + enum config_scope origin; > + /* The literal command to run. */ > + struct strbuf command; "char *" would suffice? The tests look fine.
On Sat, Jan 30, 2021 at 07:10:11PM -0800, Jonathan Tan wrote: > > > Teach 'git hook list <hookname>', which checks the known configs in > > order to create an ordered list of hooks to run on a given hook event. > > > > Multiple commands can be specified for a given hook by providing > > multiple "hook.<hookname>.command = <path-to-hook>" lines. Hooks will be > > run in config order. If more properties need to be set on a given hook > > in the future, commands can also be specified by providing > > "hook.<hookname>.command = <hookcmd-name>", as well as a "[hookcmd > > <hookcmd-name>]" subsection; at minimum, this subsection must contain a > > "hookcmd.<hookcmd-name>.command = <path-to-hook>" line. > > I learned later that this isn't true - in patch 6, the commit message > and one of the tests therein describe being able to skip a previously > inline command by making a hookcmd section of the same name and just > specifying "skip = true" there (without any command). > > Maybe just delete the "at minimum" part. Thanks, nice catch. I dropped "at minimum" and s/must/should/. Since I received feedback during the dogfood internally that there's no documentation on "hookcmd.<thing>.skip" whatsoever, I'll try to make a more detailed overview of hookcmd acting as an alias in the user-facing docs in that commit. > > > +static int list(int argc, const char **argv, const char *prefix) > > { > > - struct option builtin_hook_options[] = { > > + struct list_head *head, *pos; > > + struct hook *item; > > You asked for review on nits too so here's one: "item" should be > declared in the list_for_each block. (That also makes it easier to see > that we don't need to free it.) Ok, done. > > > diff --git a/hook.c b/hook.c > > new file mode 100644 > > index 0000000000..937dc768c8 > > --- /dev/null > > +++ b/hook.c > > @@ -0,0 +1,115 @@ > > +#include "cache.h" > > + > > +#include "hook.h" > > +#include "config.h" > > Usually we put all the includes together without any intervening blank > lines. Done. > > > +static void append_or_move_hook(struct list_head *head, const char *command) > > +{ > > + struct list_head *pos = NULL, *tmp = NULL; > > + struct hook *to_add = NULL; > > + > > + /* > > + * remove the prior entry with this command; we'll replace it at the > > + * end. > > + */ > > + list_for_each_safe(pos, tmp, head) { > > + struct hook *it = list_entry(pos, struct hook, list); > > + if (!strcmp(it->command.buf, command)) { > > + list_del(pos); > > + /* we'll simply move the hook to the end */ > > + to_add = it; > > "break" here? I think it's safe to do so, but I think I left it out in case duplicates do make it into the list somehow. But if they're always being inserted via "append_or_move_hook()" that should not be an issue, so I'll add the break. In fact, fixing this exposed a bug. Later, I add using 'pos' instead of 'head': list_add_tail(&to_add->list, pos); When I'm guaranteed to iterate to the end of the list, that works fine, because in this implementation the last element of the list has "->next" set back to "head". But when 'pos' isn't sure to be at the end of the list, it breaks the list. Whoops.. :) > > > + } > > + } > > + > > + if (!to_add) { > > + /* adding a new hook, not moving an old one */ > > + to_add = xmalloc(sizeof(struct hook)); > > Style is to write sizeof(*to_add), I think. Sure. > > [snip] > > > +struct hook_config_cb > > +{ > > + struct strbuf *hookname; > > struct declarations have "{" not on a line on its own. Sure, I can change it. Although, 'git grep -E "struct \w+$"' tells me there are a few other offenders :) But the count (60ish minus doc/relnotes references) is much lower than 'git grep -E "struct \w+ \{$"' (800+ matches) so I'm definitely doing it wrong :D > > Also, "hookname" could just be a char *? Hrmph. I think my C++ background is showing - to me, calling ".buf" (which is cheap) a few times is a small price to pay to get length info and so on for free. "hookname" can come from the user - "git hook (list|run) repo-special-magic-hook" - so I worry about leaving it as a raw char* with no size info associated. Am I being too paranoid? > > > + struct list_head *list; > > +}; > > + > > +static int hook_config_lookup(const char *key, const char *value, void *cb_data) > > +{ > > + struct hook_config_cb *data = cb_data; > > + const char *hook_key = data->hookname->buf; > > + struct list_head *head = data->list; > > + > > + if (!strcmp(key, hook_key)) { > > + const char *command = value; > > + struct strbuf hookcmd_name = STRBUF_INIT; > > + > > + /* Check if a hookcmd with that name exists. */ > > + strbuf_addf(&hookcmd_name, "hookcmd.%s.command", command); > > + git_config_get_value(hookcmd_name.buf, &command); > > So we don't really care whether git_config_get_value returns 0 or 1 as > long as it doesn't touch "command" if there is no such hookcmd. That > fits with how git_config_get_value() is documented, so that's great. > Perhaps better to document as: > > If a hookcmd.%s.command config exists, replace the command with the > value of that config. (If not, do nothing - git_config_get_value() is > documented to not overwrite the value argument in this case.) OK. Thanks, done. > > > + > > + if (!command) { > > + strbuf_release(&hookcmd_name); > > + BUG("git_config_get_value overwrote a string it shouldn't have"); > > + } > > + > > + /* > > + * TODO: implement an option-getting callback, e.g. > > + * get configs by pattern hookcmd.$value.* > > + * for each key+value, do_callback(key, value, cb_data) > > + */ > > + > > + append_or_move_hook(head, command); > > + > > + strbuf_release(&hookcmd_name); > > + } > > + > > + return 0; > > +} > > + > > +struct list_head* hook_list(const struct strbuf* hookname) > > "const char *hookname" should suffice? > > Also, search for "* " and replace with " *" where applicable (also in > the .h file). See above. > > > +{ > > + struct strbuf hook_key = STRBUF_INIT; > > + struct list_head *hook_head = xmalloc(sizeof(struct list_head)); > > + struct hook_config_cb cb_data = { &hook_key, hook_head }; > > + > > + INIT_LIST_HEAD(hook_head); > > + > > + if (!hookname) > > + return NULL; > > + > > + strbuf_addf(&hook_key, "hook.%s.command", hookname->buf); > > + > > + git_config(hook_config_lookup, (void*)&cb_data); > > Do we need this void* cast? Nope. Dropped, thanks. > > > + > > + strbuf_release(&hook_key); > > + return hook_head; > > +} > > diff --git a/hook.h b/hook.h > > new file mode 100644 > > index 0000000000..8ffc4f14b6 > > --- /dev/null > > +++ b/hook.h > > @@ -0,0 +1,26 @@ > > +#include "config.h" > > +#include "list.h" > > +#include "strbuf.h" > > + > > +struct hook > > +{ > > + struct list_head list; > > + /* > > + * Config file which holds the hook.*.command definition. > > + * (This has nothing to do with the hookcmd.<name>.* configs.) > > + */ > > + enum config_scope origin; > > + /* The literal command to run. */ > > + struct strbuf command; > > "char *" would suffice? Since 'command' comes directly from user input and is executed, I'm nervous about using a char* instead of a strbuf even more so than for the hookname. > > The tests look fine. Thanks for the nitpicky review, it was great! :) - Emily
diff --git a/Documentation/config/hook.txt b/Documentation/config/hook.txt new file mode 100644 index 0000000000..71449ecbc7 --- /dev/null +++ b/Documentation/config/hook.txt @@ -0,0 +1,9 @@ +hook.<command>.command:: + A command to execute during the <command> hook event. This can be an + executable on your device, a oneliner for your shell, or the name of a + hookcmd. See linkgit:git-hook[1]. + +hookcmd.<name>.command:: + A command to execute during a hook for which <name> has been specified + as a command. This can be an executable on your device or a oneliner for + your shell. See linkgit:git-hook[1]. diff --git a/Documentation/git-hook.txt b/Documentation/git-hook.txt index 9eeab0009d..f19875ed68 100644 --- a/Documentation/git-hook.txt +++ b/Documentation/git-hook.txt @@ -8,12 +8,65 @@ git-hook - Manage configured hooks SYNOPSIS -------- [verse] -'git hook' +'git hook' list <hook-name> DESCRIPTION ----------- -A placeholder command. Later, you will be able to list, add, and modify hooks -with this command. +You can list configured hooks with this command. Later, you will be able to run, +add, and modify hooks with this command. + +This command parses the default configuration files for sections `hook` and +`hookcmd`. `hook` is used to describe the commands which will be run during a +particular hook event; commands are run in the order Git encounters them during +the configuration parse (see linkgit:git-config[1]). `hookcmd` is used to +describe attributes of a specific command. If additional attributes don't need +to be specified, a command to run can be specified directly in the `hook` +section; if a `hookcmd` by that name isn't found, Git will attempt to run the +provided value directly. For example: + +Global config +---- + [hook "post-commit"] + command = "linter" + command = "~/typocheck.sh" + + [hookcmd "linter"] + command = "/bin/linter --c" +---- + +Local config +---- + [hook "prepare-commit-msg"] + command = "linter" + [hook "post-commit"] + command = "python ~/run-test-suite.py" +---- + +With these configs, you'd then see: + +---- +$ git hook list "post-commit" +global: /bin/linter --c +global: ~/typocheck.sh +local: python ~/run-test-suite.py + +$ git hook list "prepare-commit-msg" +local: /bin/linter --c +---- + +COMMANDS +-------- + +list `<hook-name>`:: + +List the hooks which have been configured for `<hook-name>`. Hooks appear +in the order they should be run, and print the config scope where the relevant +`hook.<hook-name>.command` was specified, not the `hookcmd` (if applicable). +This output is human-readable and the format is subject to change over time. + +CONFIGURATION +------------- +include::config/hook.txt[] GIT --- diff --git a/Makefile b/Makefile index 24cee44400..d9f43dc8fe 100644 --- a/Makefile +++ b/Makefile @@ -904,6 +904,7 @@ LIB_OBJS += grep.o LIB_OBJS += hashmap.o LIB_OBJS += help.o LIB_OBJS += hex.o +LIB_OBJS += hook.o LIB_OBJS += ident.o LIB_OBJS += json-writer.o LIB_OBJS += kwset.o diff --git a/builtin/hook.c b/builtin/hook.c index b2bbc84d4d..4d36de52f8 100644 --- a/builtin/hook.c +++ b/builtin/hook.c @@ -1,21 +1,69 @@ #include "cache.h" #include "builtin.h" +#include "config.h" +#include "hook.h" #include "parse-options.h" +#include "strbuf.h" static const char * const builtin_hook_usage[] = { - N_("git hook"), + N_("git hook list <hookname>"), NULL }; -int cmd_hook(int argc, const char **argv, const char *prefix) +static int list(int argc, const char **argv, const char *prefix) { - struct option builtin_hook_options[] = { + struct list_head *head, *pos; + struct hook *item; + struct strbuf hookname = STRBUF_INIT; + + struct option list_options[] = { OPT_END(), }; - argc = parse_options(argc, argv, prefix, builtin_hook_options, + argc = parse_options(argc, argv, prefix, list_options, builtin_hook_usage, 0); + if (argc < 1) { + usage_msg_opt(_("You must specify a hook event name to list."), + builtin_hook_usage, list_options); + } + + strbuf_addstr(&hookname, argv[0]); + + head = hook_list(&hookname); + + if (list_empty(head)) { + printf(_("no commands configured for hook '%s'\n"), + hookname.buf); + strbuf_release(&hookname); + return 0; + } + + list_for_each(pos, head) { + item = list_entry(pos, struct hook, list); + if (item) + printf("%s: %s\n", + config_scope_name(item->origin), + item->command.buf); + } + + clear_hook_list(head); + strbuf_release(&hookname); + return 0; } + +int cmd_hook(int argc, const char **argv, const char *prefix) +{ + struct option builtin_hook_options[] = { + OPT_END(), + }; + if (argc < 2) + usage_with_options(builtin_hook_usage, builtin_hook_options); + + if (!strcmp(argv[1], "list")) + return list(argc - 1, argv + 1, prefix); + + usage_with_options(builtin_hook_usage, builtin_hook_options); +} diff --git a/hook.c b/hook.c new file mode 100644 index 0000000000..937dc768c8 --- /dev/null +++ b/hook.c @@ -0,0 +1,115 @@ +#include "cache.h" + +#include "hook.h" +#include "config.h" + +void free_hook(struct hook *ptr) +{ + if (ptr) { + strbuf_release(&ptr->command); + free(ptr); + } +} + +static void append_or_move_hook(struct list_head *head, const char *command) +{ + struct list_head *pos = NULL, *tmp = NULL; + struct hook *to_add = NULL; + + /* + * remove the prior entry with this command; we'll replace it at the + * end. + */ + list_for_each_safe(pos, tmp, head) { + struct hook *it = list_entry(pos, struct hook, list); + if (!strcmp(it->command.buf, command)) { + list_del(pos); + /* we'll simply move the hook to the end */ + to_add = it; + } + } + + if (!to_add) { + /* adding a new hook, not moving an old one */ + to_add = xmalloc(sizeof(struct hook)); + strbuf_init(&to_add->command, 0); + strbuf_addstr(&to_add->command, command); + } + + /* re-set the scope so we show where an override was specified */ + to_add->origin = current_config_scope(); + + list_add_tail(&to_add->list, pos); +} + +static void remove_hook(struct list_head *to_remove) +{ + struct hook *hook_to_remove = list_entry(to_remove, struct hook, list); + list_del(to_remove); + free_hook(hook_to_remove); +} + +void clear_hook_list(struct list_head *head) +{ + struct list_head *pos, *tmp; + list_for_each_safe(pos, tmp, head) + remove_hook(pos); +} + +struct hook_config_cb +{ + struct strbuf *hookname; + struct list_head *list; +}; + +static int hook_config_lookup(const char *key, const char *value, void *cb_data) +{ + struct hook_config_cb *data = cb_data; + const char *hook_key = data->hookname->buf; + struct list_head *head = data->list; + + if (!strcmp(key, hook_key)) { + const char *command = value; + struct strbuf hookcmd_name = STRBUF_INIT; + + /* Check if a hookcmd with that name exists. */ + strbuf_addf(&hookcmd_name, "hookcmd.%s.command", command); + git_config_get_value(hookcmd_name.buf, &command); + + if (!command) { + strbuf_release(&hookcmd_name); + BUG("git_config_get_value overwrote a string it shouldn't have"); + } + + /* + * TODO: implement an option-getting callback, e.g. + * get configs by pattern hookcmd.$value.* + * for each key+value, do_callback(key, value, cb_data) + */ + + append_or_move_hook(head, command); + + strbuf_release(&hookcmd_name); + } + + return 0; +} + +struct list_head* hook_list(const struct strbuf* hookname) +{ + struct strbuf hook_key = STRBUF_INIT; + struct list_head *hook_head = xmalloc(sizeof(struct list_head)); + struct hook_config_cb cb_data = { &hook_key, hook_head }; + + INIT_LIST_HEAD(hook_head); + + if (!hookname) + return NULL; + + strbuf_addf(&hook_key, "hook.%s.command", hookname->buf); + + git_config(hook_config_lookup, (void*)&cb_data); + + strbuf_release(&hook_key); + return hook_head; +} diff --git a/hook.h b/hook.h new file mode 100644 index 0000000000..8ffc4f14b6 --- /dev/null +++ b/hook.h @@ -0,0 +1,26 @@ +#include "config.h" +#include "list.h" +#include "strbuf.h" + +struct hook +{ + struct list_head list; + /* + * Config file which holds the hook.*.command definition. + * (This has nothing to do with the hookcmd.<name>.* configs.) + */ + enum config_scope origin; + /* The literal command to run. */ + struct strbuf command; +}; + +/* + * Provides a linked list of 'struct hook' detailing commands which should run + * in response to the 'hookname' event, in execution order. + */ +struct list_head* hook_list(const struct strbuf *hookname); + +/* Free memory associated with a 'struct hook' */ +void free_hook(struct hook *ptr); +/* Empties the list at 'head', calling 'free_hook()' on each entry */ +void clear_hook_list(struct list_head *head); diff --git a/t/t1360-config-based-hooks.sh b/t/t1360-config-based-hooks.sh index 34b0df5216..6e4a3e763f 100755 --- a/t/t1360-config-based-hooks.sh +++ b/t/t1360-config-based-hooks.sh @@ -4,8 +4,85 @@ test_description='config-managed multihooks, including git-hook command' . ./test-lib.sh -test_expect_success 'git hook command does not crash' ' - git hook +ROOT= +if test_have_prereq MINGW +then + # In Git for Windows, Unix-like paths work only in shell scripts; + # `git.exe`, however, will prefix them with the pseudo root directory + # (of the Unix shell). Let's accommodate for that. + ROOT="$(cd / && pwd)" +fi + +setup_hooks () { + test_config hook.pre-commit.command "/path/ghi" --add + test_config_global hook.pre-commit.command "/path/def" --add +} + +setup_hookcmd () { + test_config hook.pre-commit.command "abc" --add + test_config_global hookcmd.abc.command "/path/abc" --add +} + +test_expect_success 'git hook rejects commands without a mode' ' + test_must_fail git hook pre-commit +' + + +test_expect_success 'git hook rejects commands without a hookname' ' + test_must_fail git hook list +' + +test_expect_success 'git hook runs outside of a repo' ' + setup_hooks && + + cat >expected <<-EOF && + global: $ROOT/path/def + EOF + + nongit git config --list --global && + + nongit git hook list pre-commit >actual && + test_cmp expected actual +' + +test_expect_success 'git hook list orders by config order' ' + setup_hooks && + + cat >expected <<-EOF && + global: $ROOT/path/def + local: $ROOT/path/ghi + EOF + + git hook list pre-commit >actual && + test_cmp expected actual +' + +test_expect_success 'git hook list dereferences a hookcmd' ' + setup_hooks && + setup_hookcmd && + + cat >expected <<-EOF && + global: $ROOT/path/def + local: $ROOT/path/ghi + local: $ROOT/path/abc + EOF + + git hook list pre-commit >actual && + test_cmp expected actual +' + +test_expect_success 'git hook list reorders on duplicate commands' ' + setup_hooks && + + test_config hook.pre-commit.command "/path/def" --add && + + cat >expected <<-EOF && + local: $ROOT/path/ghi + local: $ROOT/path/def + EOF + + git hook list pre-commit >actual && + test_cmp expected actual ' test_done
Teach 'git hook list <hookname>', which checks the known configs in order to create an ordered list of hooks to run on a given hook event. Multiple commands can be specified for a given hook by providing multiple "hook.<hookname>.command = <path-to-hook>" lines. Hooks will be run in config order. If more properties need to be set on a given hook in the future, commands can also be specified by providing "hook.<hookname>.command = <hookcmd-name>", as well as a "[hookcmd <hookcmd-name>]" subsection; at minimum, this subsection must contain a "hookcmd.<hookcmd-name>.command = <path-to-hook>" line. For example: $ git config --list | grep ^hook hook.pre-commit.command=baz hook.pre-commit.command=~/bar.sh hookcmd.baz.command=~/baz/from/hookcmd.sh $ git hook list pre-commit global: ~/baz/from/hookcmd.sh local: ~/bar.sh Signed-off-by: Emily Shaffer <emilyshaffer@google.com> --- Notes: Since v4, updated the sample in the commit message to reflect reality better. Since v4, more work on the documentation. Also a slight change to the output format (space instead of tab). Documentation/config/hook.txt | 9 +++ Documentation/git-hook.txt | 59 ++++++++++++++++- Makefile | 1 + builtin/hook.c | 56 +++++++++++++++-- hook.c | 115 ++++++++++++++++++++++++++++++++++ hook.h | 26 ++++++++ t/t1360-config-based-hooks.sh | 81 +++++++++++++++++++++++- 7 files changed, 338 insertions(+), 9 deletions(-) create mode 100644 Documentation/config/hook.txt create mode 100644 hook.c create mode 100644 hook.h