[PATCH v4 00/13] Add struct strmap and associated utility functions
- From
Elijah Newren via GitGitGadget <gitgitgadget@gmail.com>
- Date
- Nov 5, 2020, 00:22 UTC
- Message-ID
- <pull.835.v4.git.git.1604535765.gitgitgadget@gmail.com>
- In-Reply-To
- <pull.835.v3.git.git.1604343313.gitgitgadget@gmail.com>
Here I introduce a new strmap type (and strintmap and strset), which my new merge backed, merge-ort, uses heavily. (I also made significant use of it in my changes to diffcore-rename). This strmap type was based on Peff's proposal from a couple years ago[1], but has additions that I made as I used it, and a number of additions/changes suggested by Peff in his reviews. I also start the series off with some changes to hashmap, based on Peff's feedback on v1 & v2.
NOTE: While en/merge-ort-impl depends on this series, there are no changes in v4 that affect it so en/merge-ort-impl does not need a reroll.
Changes since v3 (almost all of which were suggestions from Peff):
* Fix pointer math due to platform differences in FLEX_ALLOC definition, and a few other FLEXPTR_ALLOC_STR cleanups * Define strmap_for_each_entry in terms of hashmap_for_each_entry instead of lower level functions * Use simpler _INIT macros * Remove strset_check_and_add() from API as per Peff's suggestion (merge-ort doesn't need it; we can add it later) * Update comments and commit messages to update now obsolete statements due to changes from earlier reviews
[1] https://lore.kernel.org/git/20180906191203.GA26184@sigill.intra.peff.net/
Elijah Newren (13): hashmap: add usage documentation explaining hashmap_free[_entries]() hashmap: adjust spacing to fix argument alignment hashmap: allow re-use after hashmap_free() hashmap: introduce a new hashmap_partial_clear() hashmap: provide deallocation function names strmap: new utility functions strmap: add more utility functions strmap: enable faster clearing and reusing of strmaps strmap: add functions facilitating use as a string->int map strmap: add a strset sub-type strmap: enable allocations to come from a mem_pool strmap: take advantage of FLEXPTR_ALLOC_STR when relevant Use new HASHMAP_INIT macro to simplify hashmap initialization
Makefile | 1 + add-interactive.c | 2 +- attr.c | 26 ++-- blame.c | 2 +- bloom.c | 5 +- builtin/difftool.c | 9 +- builtin/fetch.c | 6 +- builtin/shortlog.c | 2 +- config.c | 2 +- diff.c | 4 +- diffcore-rename.c | 2 +- dir.c | 8 +- hashmap.c | 74 +++++++---- hashmap.h | 91 +++++++++++--- merge-recursive.c | 6 +- name-hash.c | 4 +- object.c | 2 +- oidmap.c | 2 +- patch-ids.c | 2 +- range-diff.c | 6 +- ref-filter.c | 2 +- revision.c | 11 +- sequencer.c | 4 +- strmap.c | 151 ++++++++++++++++++++++ strmap.h | 270 ++++++++++++++++++++++++++++++++++++++++ submodule-config.c | 4 +- t/helper/test-hashmap.c | 9 +- 27 files changed, 593 insertions(+), 114 deletions(-) create mode 100644 strmap.c create mode 100644 strmap.h
base-commit: d4a392452e292ff924e79ec8458611c0f679d6d4 Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-835%2Fnewren%2Fstrmap-v4 Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-835/newren/strmap-v4 Pull-Request: https://github.com/git/git/pull/835
Range-diff vs v3:
1: af6b6fcb46 = 1: af6b6fcb46 hashmap: add usage documentation explaining hashmap_free[_entries]()
2: 591161fd78 = 2: 591161fd78 hashmap: adjust spacing to fix argument alignment
3: f2718d036d = 3: f2718d036d hashmap: allow re-use after hashmap_free()
4: 61f1da3c51 = 4: 61f1da3c51 hashmap: introduce a new hashmap_partial_clear()
5: 861e8d65ae = 5: 861e8d65ae hashmap: provide deallocation function names
6: 448d3b219f = 6: 448d3b219f strmap: new utility functions
7: 42633b8d03 ! 7: 5e8004c728 strmap: add more utility functions
@@ strmap.h: void *strmap_get(struct strmap *map, const char *str);
+ * iterate through @map using @iter, @var is a pointer to a type strmap_entry
+ */
+#define strmap_for_each_entry(mystrmap, iter, var) \
-+ for (var = hashmap_iter_first_entry_offset(&(mystrmap)->map, iter, 0); \
-+ var; \
-+ var = hashmap_iter_next_entry_offset(iter, 0))
++ hashmap_for_each_entry(&(mystrmap)->map, iter, var, ent)
+
#endif /* STRMAP_H */
8: ea942eb803 = 8: fd96e9fc8d strmap: enable faster clearing and reusing of strmaps
9: c1d2172171 ! 9: f499934f54 strmap: add functions facilitating use as a string->int map
@@ Commit message
isn't the case when we're storing an int value directly in the void*
slot instead of using the void* slot as a pointer to data.
- A note on the name: if anyone has a better name suggestion than
- strintmap, I'm happy to take it. It seems slightly unwieldy, but I have
- not been able to come up with a better name.
-
Signed-off-by: Elijah Newren <newren@gmail.com>
## strmap.c ##
@@ strmap.h: int cmp_strmap_entry(const void *hashmap_cmp_fn_data,
.strdup_strings = 1, \
}
+#define STRINTMAP_INIT { \
-+ .map.map = HASHMAP_INIT(cmp_strmap_entry, NULL), \
-+ .map.strdup_strings = 1, \
-+ .default_value = 0, \
-+ }
++ .map = STRMAP_INIT, \
++ .default_value = 0, \
++ }
/*
* Initialize the members of the strmap. Any keys added to the strmap will
@@ strmap.h: static inline int strmap_empty(struct strmap *map)
- var; \
- var = hashmap_iter_next_entry_offset(iter, 0))
+ #define strmap_for_each_entry(mystrmap, iter, var) \
+ hashmap_for_each_entry(&(mystrmap)->map, iter, var, ent)
+
+/*
@@ strmap.h: static inline int strmap_empty(struct strmap *map)
+ * Primary differences:
+ * 1) Since the void* value is just an int in disguise, there is no value
+ * to free. (Thus one fewer argument to strintmap_clear)
-+ * 2) strintmap_get() returns an int; it also requires an extra parameter to
-+ * be specified so it knows what value to return if the underlying strmap
-+ * has not key matching the given string.
++ * 2) strintmap_get() returns an int, or returns the default_value if the
++ * key is not found in the strintmap.
+ * 3) No strmap_put() equivalent; strintmap_set() and strintmap_incr()
+ * instead.
+ */
10: 0f57735f5e ! 10: ee1ec55f1b strmap: add a strset sub-type
@@ Commit message
free_values argument to *_clear(), and the *_get() function), and
strset_add() is chosen as the API instead of strset_put().
- Finally, shortlog already had a more minimal strset API; so this adds a
- strset_check_and_add() function for its benefit to allow it to switch
- over to this strset implementation.
-
Signed-off-by: Elijah Newren <newren@gmail.com>
- ## strmap.c ##
-@@ strmap.c: void strintmap_incr(struct strintmap *map, const char *str, intptr_t amt)
- else
- strintmap_set(map, str, map->default_value + amt);
- }
-+
-+int strset_check_and_add(struct strset *set, const char *str)
-+{
-+ if (strset_contains(set, str))
-+ return 1;
-+ strset_add(set, str);
-+ return 0;
-+}
-
## strmap.h ##
@@ strmap.h: int cmp_strmap_entry(const void *hashmap_cmp_fn_data,
- .map.strdup_strings = 1, \
- .default_value = 0, \
- }
-+#define STRSET_INIT { \
-+ .map.map = HASHMAP_INIT(cmp_strmap_entry, NULL), \
-+ .map.strdup_strings = 1, \
-+ }
+ .map = STRMAP_INIT, \
+ .default_value = 0, \
+ }
++#define STRSET_INIT { .map = STRMAP_INIT }
/*
* Initialize the members of the strmap. Any keys added to the strmap will
@@ strmap.h: static inline void strintmap_set(struct strintmap *map, const char *st
+{
+ strmap_put(&set->map, str, NULL);
+}
-+
-+/* Returns 1 if str already in set. Otherwise adds str to set and returns 0 */
-+int strset_check_and_add(struct strset *set, const char *str);
+
#endif /* STRMAP_H */
11: 980537e877 = 11: 73a57045c3 strmap: enable allocations to come from a mem_pool
12: 7f93cbb525 ! 12: 0352260de4 strmap: take advantage of FLEXPTR_ALLOC_STR when relevant
@@ strmap.c: static void strmap_free_entries_(struct strmap *map, int free_values)
}
}
-@@ strmap.c: void *strmap_put(struct strmap *map, const char *str, void *data)
- old = entry->value;
+@@ strmap.c: void strmap_partial_clear(struct strmap *map, int free_values)
+ void *strmap_put(struct strmap *map, const char *str, void *data)
+ {
+ struct strmap_entry *entry = find_strmap_entry(map, str);
+- void *old = NULL;
+
+ if (entry) {
+- old = entry->value;
++ void *old = entry->value;
entry->value = data;
- } else {
+- } else {
- const char *key = str;
-
- entry = map->pool ? mem_pool_alloc(map->pool, sizeof(*entry))
- : xmalloc(sizeof(*entry));
-+ if (map->strdup_strings) {
-+ if (!map->pool) {
-+ FLEXPTR_ALLOC_STR(entry, key, str);
-+ } else {
-+ /* Remember +1 for nul byte twice below */
-+ size_t len = strlen(str);
-+ entry = mem_pool_alloc(map->pool,
-+ st_add3(sizeof(*entry), len, 1));
-+ memcpy(entry->keydata, str, len+1);
-+ }
-+ } else if (!map->pool) {
-+ entry = xmalloc(sizeof(*entry));
-+ } else {
-+ entry = mem_pool_alloc(map->pool, sizeof(*entry));
-+ }
- hashmap_entry_init(&entry->ent, strhash(str));
--
+- hashmap_entry_init(&entry->ent, strhash(str));
++ return old;
++ }
+
- if (map->strdup_strings)
- key = map->pool ? mem_pool_strdup(map->pool, str)
- : xstrdup(str);
- entry->key = key;
-+ entry->key = map->strdup_strings ? entry->keydata : str;
- entry->value = data;
- hashmap_add(&map->map, &entry->ent);
+- entry->value = data;
+- hashmap_add(&map->map, &entry->ent);
++ if (map->strdup_strings) {
++ if (!map->pool) {
++ FLEXPTR_ALLOC_STR(entry, key, str);
++ } else {
++ size_t len = st_add(strlen(str), 1); /* include NUL */
++ entry = mem_pool_alloc(map->pool,
++ st_add(sizeof(*entry), len));
++ memcpy(entry + 1, str, len);
++ entry->key = (void *)(entry + 1);
++ }
++ } else if (!map->pool) {
++ entry = xmalloc(sizeof(*entry));
++ } else {
++ entry = mem_pool_alloc(map->pool, sizeof(*entry));
}
+- return old;
++ hashmap_entry_init(&entry->ent, strhash(str));
++ if (!map->strdup_strings)
++ entry->key = str;
++ entry->value = data;
++ hashmap_add(&map->map, &entry->ent);
++ return NULL;
+ }
+
+ struct strmap_entry *strmap_get_entry(struct strmap *map, const char *str)
@@ strmap.c: void strmap_remove(struct strmap *map, const char *str, int free_value)
return;
if (free_value)
@@ strmap.h: struct strmap_entry {
struct hashmap_entry ent;
const char *key;
void *value;
-+ char keydata[FLEX_ARRAY]; /* if strdup_strings=1, key == &keydata[0] */
++ /* strmap_entry may be allocated extra space to store the key at end */
};
int cmp_strmap_entry(const void *hashmap_cmp_fn_data,
13: 5f41fc63e5 = 13: 617926540b Use new HASHMAP_INIT macro to simplify hashmap initialization-- gitgitgadget