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>
Johannes Schindelin committed
Apr 9, 2018 at 10:32 UTC
5221c3159f670281ff36b6adbdf568661e930b50
1 file changed
+29
-30
config.c
+29
-30
@@ -2296,7 +2296,7 @@ struct config_store_data {
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int multi_replace;
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size_t *seen;
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unsigned int seen_nr, seen_alloc;
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- enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
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+ unsigned int key_seen:1, section_seen:1, is_keys_section:1;
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};
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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)
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size_t section_len;
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struct config_store_data *store = cb;
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- switch (store->state) {
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- case KEY_SEEN:
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+ if (store->key_seen) {
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if (matches(key, value, store)) {
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if (store->seen_nr == 1 && store->multi_replace == 0) {
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warning(_("%s has multiple values"), key);
@@ -2332,8 +2331,8 @@ static int store_aux(const char *key, const char *value, void *cb)
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store->seen[store->seen_nr] = cf->do_ftell(cf);
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store->seen_nr++;
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}
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- break;
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- case SECTION_SEEN:
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+ return 0;
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+ } else if (store->is_keys_section) {
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/*
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* What we are looking for is in store->key (both
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* 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)
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if ((section_len != store->baselen) ||
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memcmp(key, store->key, section_len+1)) {
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- store->state = SECTION_END_SEEN;
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- break;
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+ store->is_keys_section = 0;
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+ return 0;
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}
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-
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/*
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* Do not increment matches: this is no match, but we
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* 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)
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ALLOC_GROW(store->seen, store->seen_nr + 1,
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store->seen_alloc);
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store->seen[store->seen_nr] = cf->do_ftell(cf);
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- /* fallthru */
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- case SECTION_END_SEEN:
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- case START:
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- if (matches(key, value, store)) {
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- ALLOC_GROW(store->seen, store->seen_nr + 1,
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- store->seen_alloc);
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- store->seen[store->seen_nr] = cf->do_ftell(cf);
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- store->state = KEY_SEEN;
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- store->seen_nr++;
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- } else {
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- if (strrchr(key, '.') - key == store->baselen &&
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- !strncmp(key, store->key, store->baselen)) {
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- store->state = SECTION_SEEN;
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- ALLOC_GROW(store->seen,
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- store->seen_nr + 1,
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- store->seen_alloc);
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- store->seen[store->seen_nr] =
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- cf->do_ftell(cf);
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- }
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+ }
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+
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+ if (matches(key, value, store)) {
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+ ALLOC_GROW(store->seen, store->seen_nr + 1,
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+ store->seen_alloc);
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+ store->seen[store->seen_nr] = cf->do_ftell(cf);
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+ store->seen_nr++;
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+ store->key_seen = 1;
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+ store->section_seen = 1;
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+ store->is_keys_section = 1;
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+ } else {
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+ if (strrchr(key, '.') - key == store->baselen &&
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+ !strncmp(key, store->key, store->baselen)) {
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+ store->section_seen = 1;
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+ store->is_keys_section = 1;
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+ ALLOC_GROW(store->seen,
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+ store->seen_nr + 1,
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+ store->seen_alloc);
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+ store->seen[store->seen_nr] =
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+ cf->do_ftell(cf);
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}
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}
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+
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return 0;
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}
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@@ -2637,7 +2637,6 @@ int git_config_set_multivar_in_file_gently(const char *config_filename,
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ALLOC_GROW(store.seen, 1, store.seen_alloc);
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store.seen[0] = 0;
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- store.state = START;
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store.seen_nr = 0;
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/*
@@ -2705,7 +2704,7 @@ int git_config_set_multivar_in_file_gently(const char *config_filename,
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new_line = 0;
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if (store.seen[i] == 0) {
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store.seen[i] = copy_end = contents_sz;
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- } else if (store.state != KEY_SEEN) {
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+ } else if (!store.key_seen) {
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copy_end = store.seen[i];
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} else
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copy_end = find_beginning_of_line(
@@ -2729,7 +2728,7 @@ int git_config_set_multivar_in_file_gently(const char *config_filename,
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/* write the pair (value == NULL means unset) */
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if (value != NULL) {
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- if (store.state == START) {
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+ if (!store.section_seen) {
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if (write_section(fd, key, &store) < 0)
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goto write_err_out;
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}