git_config_set: do not use a state machine

While a neat theoretical construct, state machines are hard to read. In
this instance, it does not even make a whole lot of sense because we are
more interested in flags, anyway: has the section been seen? Has the key
been seen? Does the current section match the key we are looking for?

Besides, the state `SECTION_SEEN` was named in a misleading way: it did
not indicate that we saw the section matching the key we are looking
for, but it instead indicated that we are *currently* in that section.

Let's just replace the state machine logic by clear and obvious flags.

This will also make it easier to review the upcoming patches to use the
newly-introduced `event_fn` callback of the config parser.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Johannes Schindelin 2018-04-09 10:32:17 +02:00 committed by Junio C Hamano
parent 668b9ade6b
commit 5221c3159f

View File

@ -2296,7 +2296,7 @@ struct config_store_data {
int multi_replace;
size_t *seen;
unsigned int seen_nr, seen_alloc;
enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
unsigned int key_seen:1, section_seen:1, is_keys_section:1;
};
static int matches(const char *key, const char *value,
@ -2319,8 +2319,7 @@ static int store_aux(const char *key, const char *value, void *cb)
size_t section_len;
struct config_store_data *store = cb;
switch (store->state) {
case KEY_SEEN:
if (store->key_seen) {
if (matches(key, value, store)) {
if (store->seen_nr == 1 && store->multi_replace == 0) {
warning(_("%s has multiple values"), key);
@ -2332,8 +2331,8 @@ static int store_aux(const char *key, const char *value, void *cb)
store->seen[store->seen_nr] = cf->do_ftell(cf);
store->seen_nr++;
}
break;
case SECTION_SEEN:
return 0;
} else if (store->is_keys_section) {
/*
* What we are looking for is in store->key (both
* section and var), and its section part is baselen
@ -2348,10 +2347,9 @@ static int store_aux(const char *key, const char *value, void *cb)
if ((section_len != store->baselen) ||
memcmp(key, store->key, section_len+1)) {
store->state = SECTION_END_SEEN;
break;
store->is_keys_section = 0;
return 0;
}
/*
* Do not increment matches: this is no match, but we
* just made sure we are in the desired section.
@ -2359,27 +2357,29 @@ static int store_aux(const char *key, const char *value, void *cb)
ALLOC_GROW(store->seen, store->seen_nr + 1,
store->seen_alloc);
store->seen[store->seen_nr] = cf->do_ftell(cf);
/* fallthru */
case SECTION_END_SEEN:
case START:
if (matches(key, value, store)) {
ALLOC_GROW(store->seen, store->seen_nr + 1,
store->seen_alloc);
store->seen[store->seen_nr] = cf->do_ftell(cf);
store->state = KEY_SEEN;
store->seen_nr++;
} else {
if (strrchr(key, '.') - key == store->baselen &&
!strncmp(key, store->key, store->baselen)) {
store->state = SECTION_SEEN;
ALLOC_GROW(store->seen,
store->seen_nr + 1,
store->seen_alloc);
store->seen[store->seen_nr] =
cf->do_ftell(cf);
}
}
if (matches(key, value, store)) {
ALLOC_GROW(store->seen, store->seen_nr + 1,
store->seen_alloc);
store->seen[store->seen_nr] = cf->do_ftell(cf);
store->seen_nr++;
store->key_seen = 1;
store->section_seen = 1;
store->is_keys_section = 1;
} else {
if (strrchr(key, '.') - key == store->baselen &&
!strncmp(key, store->key, store->baselen)) {
store->section_seen = 1;
store->is_keys_section = 1;
ALLOC_GROW(store->seen,
store->seen_nr + 1,
store->seen_alloc);
store->seen[store->seen_nr] =
cf->do_ftell(cf);
}
}
return 0;
}
@ -2637,7 +2637,6 @@ int git_config_set_multivar_in_file_gently(const char *config_filename,
ALLOC_GROW(store.seen, 1, store.seen_alloc);
store.seen[0] = 0;
store.state = START;
store.seen_nr = 0;
/*
@ -2705,7 +2704,7 @@ int git_config_set_multivar_in_file_gently(const char *config_filename,
new_line = 0;
if (store.seen[i] == 0) {
store.seen[i] = copy_end = contents_sz;
} else if (store.state != KEY_SEEN) {
} else if (!store.key_seen) {
copy_end = store.seen[i];
} else
copy_end = find_beginning_of_line(
@ -2729,7 +2728,7 @@ int git_config_set_multivar_in_file_gently(const char *config_filename,
/* write the pair (value == NULL means unset) */
if (value != NULL) {
if (store.state == START) {
if (!store.section_seen) {
if (write_section(fd, key, &store) < 0)
goto write_err_out;
}