[PATCH v3 13/16] reftable: rest of library
From: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
---
Makefile | 4 +
reftable/VERSION | 1 +
reftable/dump.c | 212 ++++++
reftable/merged.c | 366 ++++++++++
reftable/merged.h | 35 +
reftable/merged_test.c | 333 ++++++++++
reftable/pq.c | 115 ++++
reftable/pq.h | 32 +
reftable/refname.c | 209 ++++++
reftable/refname.h | 29 +
reftable/refname_test.c | 100 +++
reftable/reftable-generic.h | 49 ++
reftable/reftable-merged.h | 68 ++
reftable/reftable-stack.h | 116 ++++
reftable/reftable.c | 98 +++
reftable/stack.c | 1247 +++++++++++++++++++++++++++++++++++
reftable/stack.h | 41 ++
reftable/stack_test.c | 781 ++++++++++++++++++++++
t/helper/test-reftable.c | 3 +
19 files changed, 3839 insertions(+)
create mode 100644 reftable/VERSION
create mode 100644 reftable/dump.c
create mode 100644 reftable/merged.c
create mode 100644 reftable/merged.h
create mode 100644 reftable/merged_test.c
create mode 100644 reftable/pq.c
create mode 100644 reftable/pq.h
create mode 100644 reftable/refname.c
create mode 100644 reftable/refname.h
create mode 100644 reftable/refname_test.c
create mode 100644 reftable/reftable-generic.h
create mode 100644 reftable/reftable-merged.h
create mode 100644 reftable/reftable-stack.h
create mode 100644 reftable/reftable.c
create mode 100644 reftable/stack.c
create mode 100644 reftable/stack.h
create mode 100644 reftable/stack_test.c
diff --git a/Makefile b/Makefile
index b20acdac0f..278c489da4 100644
--- a/Makefile
+++ b/Makefile
@@ -2394,10 +2394,14 @@ REFTABLE_OBJS += reftable/error.o
REFTABLE_OBJS += reftable/block.o
REFTABLE_OBJS += reftable/blocksource.o
REFTABLE_OBJS += reftable/iter.o
+REFTABLE_OBJS += reftable/merged.o
+REFTABLE_OBJS += reftable/pq.o
REFTABLE_OBJS += reftable/publicbasics.o
REFTABLE_OBJS += reftable/reader.o
REFTABLE_OBJS += reftable/record.o
+REFTABLE_OBJS += reftable/refname.o
REFTABLE_OBJS += reftable/reftable.o
+REFTABLE_OBJS += reftable/stack.o
REFTABLE_OBJS += reftable/tree.o
REFTABLE_OBJS += reftable/writer.o
REFTABLE_OBJS += reftable/zlib-compat.o
diff --git a/reftable/VERSION b/reftable/VERSION
new file mode 100644
index 0000000000..7553c395eb
--- /dev/null
+++ b/reftable/VERSION
@@ -0,0 +1 @@
+b8ec0f74c74cb6752eb2033ad8e755a9c19aad15 C: add missing header
diff --git a/reftable/dump.c b/reftable/dump.c
new file mode 100644
index 0000000000..00b444e8c9
--- /dev/null
+++ b/reftable/dump.c
@@ -0,0 +1,212 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+
+#include "reftable.h"
+#include "reftable-tests.h"
+
+static uint32_t hash_id;
+
+static int dump_table(const char *tablename)
+{
+ struct reftable_block_source src = { 0 };
+ int err = reftable_block_source_from_file(&src, tablename);
+ struct reftable_iterator it = { 0 };
+ struct reftable_ref_record ref = { 0 };
+ struct reftable_log_record log = { 0 };
+ struct reftable_reader *r = NULL;
+
+ if (err < 0)
+ return err;
+
+ err = reftable_new_reader(&r, &src, tablename);
+ if (err < 0)
+ return err;
+
+ err = reftable_reader_seek_ref(r, &it, "");
+ if (err < 0) {
+ return err;
+ }
+
+ while (1) {
+ err = reftable_iterator_next_ref(&it, &ref);
+ if (err > 0) {
+ break;
+ }
+ if (err < 0) {
+ return err;
+ }
+ reftable_ref_record_print(&ref, hash_id);
+ }
+ reftable_iterator_destroy(&it);
+ reftable_ref_record_clear(&ref);
+
+ err = reftable_reader_seek_log(r, &it, "");
+ if (err < 0) {
+ return err;
+ }
+ while (1) {
+ err = reftable_iterator_next_log(&it, &log);
+ if (err > 0) {
+ break;
+ }
+ if (err < 0) {
+ return err;
+ }
+ reftable_log_record_print(&log, hash_id);
+ }
+ reftable_iterator_destroy(&it);
+ reftable_log_record_clear(&log);
+
+ reftable_reader_free(r);
+ return 0;
+}
+
+static int compact_stack(const char *stackdir)
+{
+ struct reftable_stack *stack = NULL;
+ struct reftable_write_options cfg = {};
+
+ int err = reftable_new_stack(&stack, stackdir, cfg);
+ if (err < 0)
+ goto done;
+
+ err = reftable_stack_compact_all(stack, NULL);
+ if (err < 0)
+ goto done;
+done:
+ if (stack != NULL) {
+ reftable_stack_destroy(stack);
+ }
+ return err;
+}
+
+static int dump_stack(const char *stackdir)
+{
+ struct reftable_stack *stack = NULL;
+ struct reftable_write_options cfg = {};
+ struct reftable_iterator it = { 0 };
+ struct reftable_ref_record ref = { 0 };
+ struct reftable_log_record log = { 0 };
+ struct reftable_merged_table *merged = NULL;
+
+ int err = reftable_new_stack(&stack, stackdir, cfg);
+ if (err < 0)
+ return err;
+
+ merged = reftable_stack_merged_table(stack);
+
+ err = reftable_merged_table_seek_ref(merged, &it, "");
+ if (err < 0) {
+ return err;
+ }
+
+ while (1) {
+ err = reftable_iterator_next_ref(&it, &ref);
+ if (err > 0) {
+ break;
+ }
+ if (err < 0) {
+ return err;
+ }
+ reftable_ref_record_print(&ref, hash_id);
+ }
+ reftable_iterator_destroy(&it);
+ reftable_ref_record_clear(&ref);
+
+ err = reftable_merged_table_seek_log(merged, &it, "");
+ if (err < 0) {
+ return err;
+ }
+ while (1) {
+ err = reftable_iterator_next_log(&it, &log);
+ if (err > 0) {
+ break;
+ }
+ if (err < 0) {
+ return err;
+ }
+ reftable_log_record_print(&log, hash_id);
+ }
+ reftable_iterator_destroy(&it);
+ reftable_log_record_clear(&log);
+
+ reftable_stack_destroy(stack);
+ return 0;
+}
+
+static void print_help(void)
+{
+ printf("usage: dump [-cst] arg\n\n"
+ "options: \n"
+ " -c compact\n"
+ " -t dump table\n"
+ " -s dump stack\n"
+ " -h this help\n"
+ " -2 use SHA256\n"
+ "\n");
+}
+
+int reftable_dump_main(int argc, char *const *argv)
+{
+ int err = 0;
+ int opt;
+ int opt_dump_table = 0;
+ int opt_dump_stack = 0;
+ int opt_compact = 0;
+ const char *arg = NULL;
+ while ((opt = getopt(argc, argv, "2chts")) != -1) {
+ switch (opt) {
+ case '2':
+ hash_id = 0x73323536;
+ break;
+ case 't':
+ opt_dump_table = 1;
+ break;
+ case 's':
+ opt_dump_stack = 1;
+ break;
+ case 'c':
+ opt_compact = 1;
+ break;
+ case '?':
+ case 'h':
+ print_help();
+ return 2;
+ break;
+ }
+ }
+
+ if (argv[optind] == NULL) {
+ fprintf(stderr, "need argument\n");
+ print_help();
+ return 2;
+ }
+
+ arg = argv[optind];
+
+ if (opt_dump_table) {
+ err = dump_table(arg);
+ } else if (opt_dump_stack) {
+ err = dump_stack(arg);
+ } else if (opt_compact) {
+ err = compact_stack(arg);
+ }
+
+ if (err < 0) {
+ fprintf(stderr, "%s: %s: %s\n", argv[0], arg,
+ reftable_error_str(err));
+ return 1;
+ }
+ return 0;
+}
diff --git a/reftable/merged.c b/reftable/merged.c
new file mode 100644
index 0000000000..ed02625bb5
--- /dev/null
+++ b/reftable/merged.c
@@ -0,0 +1,366 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "merged.h"
+
+#include "constants.h"
+#include "iter.h"
+#include "pq.h"
+#include "reader.h"
+#include "record.h"
+#include "reftable-merged.h"
+#include "reftable-error.h"
+#include "system.h"
+
+static int merged_iter_init(struct merged_iter *mi)
+{
+ int i = 0;
+ for (i = 0; i < mi->stack_len; i++) {
+ struct reftable_record rec = reftable_new_record(mi->typ);
+ int err = iterator_next(&mi->stack[i], &rec);
+ if (err < 0) {
+ return err;
+ }
+
+ if (err > 0) {
+ reftable_iterator_destroy(&mi->stack[i]);
+ reftable_record_destroy(&rec);
+ } else {
+ struct pq_entry e = {
+ .rec = rec,
+ .index = i,
+ };
+ merged_iter_pqueue_add(&mi->pq, e);
+ }
+ }
+
+ return 0;
+}
+
+static void merged_iter_close(void *p)
+{
+ struct merged_iter *mi = (struct merged_iter *)p;
+ int i = 0;
+ merged_iter_pqueue_release(&mi->pq);
+ for (i = 0; i < mi->stack_len; i++) {
+ reftable_iterator_destroy(&mi->stack[i]);
+ }
+ reftable_free(mi->stack);
+}
+
+static int merged_iter_advance_nonnull_subiter(struct merged_iter *mi,
+ size_t idx)
+{
+ struct reftable_record rec = reftable_new_record(mi->typ);
+ struct pq_entry e = {
+ .rec = rec,
+ .index = idx,
+ };
+ int err = iterator_next(&mi->stack[idx], &rec);
+ if (err < 0)
+ return err;
+
+ if (err > 0) {
+ reftable_iterator_destroy(&mi->stack[idx]);
+ reftable_record_destroy(&rec);
+ return 0;
+ }
+
+ merged_iter_pqueue_add(&mi->pq, e);
+ return 0;
+}
+
+static int merged_iter_advance_subiter(struct merged_iter *mi, size_t idx)
+{
+ if (iterator_is_null(&mi->stack[idx]))
+ return 0;
+ return merged_iter_advance_nonnull_subiter(mi, idx);
+}
+
+static int merged_iter_next_entry(struct merged_iter *mi,
+ struct reftable_record *rec)
+{
+ struct strbuf entry_key = STRBUF_INIT;
+ struct pq_entry entry = { 0 };
+ int err = 0;
+
+ if (merged_iter_pqueue_is_empty(mi->pq))
+ return 1;
+
+ entry = merged_iter_pqueue_remove(&mi->pq);
+ err = merged_iter_advance_subiter(mi, entry.index);
+ if (err < 0)
+ return err;
+
+ /*
+ One can also use reftable as datacenter-local storage, where the ref
+ database is maintained in globally consistent database (eg.
+ CockroachDB or Spanner). In this scenario, replication delays together
+ with compaction may cause newer tables to contain older entries. In
+ such a deployment, the loop below must be changed to collect all
+ entries for the same key, and return new the newest one.
+ */
+ reftable_record_key(&entry.rec, &entry_key);
+ while (!merged_iter_pqueue_is_empty(mi->pq)) {
+ struct pq_entry top = merged_iter_pqueue_top(mi->pq);
+ struct strbuf k = STRBUF_INIT;
+ int err = 0, cmp = 0;
+
+ reftable_record_key(&top.rec, &k);
+
+ cmp = strbuf_cmp(&k, &entry_key);
+ strbuf_release(&k);
+
+ if (cmp > 0) {
+ break;
+ }
+
+ merged_iter_pqueue_remove(&mi->pq);
+ err = merged_iter_advance_subiter(mi, top.index);
+ if (err < 0) {
+ return err;
+ }
+ reftable_record_destroy(&top.rec);
+ }
+
+ reftable_record_copy_from(rec, &entry.rec, hash_size(mi->hash_id));
+ reftable_record_destroy(&entry.rec);
+ strbuf_release(&entry_key);
+ return 0;
+}
+
+static int merged_iter_next(struct merged_iter *mi, struct reftable_record *rec)
+{
+ while (1) {
+ int err = merged_iter_next_entry(mi, rec);
+ if (err == 0 && mi->suppress_deletions &&
+ reftable_record_is_deletion(rec)) {
+ continue;
+ }
+
+ return err;
+ }
+}
+
+static int merged_iter_next_void(void *p, struct reftable_record *rec)
+{
+ struct merged_iter *mi = (struct merged_iter *)p;
+ if (merged_iter_pqueue_is_empty(mi->pq))
+ return 1;
+
+ return merged_iter_next(mi, rec);
+}
+
+static struct reftable_iterator_vtable merged_iter_vtable = {
+ .next = &merged_iter_next_void,
+ .close = &merged_iter_close,
+};
+
+static void iterator_from_merged_iter(struct reftable_iterator *it,
+ struct merged_iter *mi)
+{
+ assert(it->ops == NULL);
+ it->iter_arg = mi;
+ it->ops = &merged_iter_vtable;
+}
+
+int reftable_new_merged_table(struct reftable_merged_table **dest,
+ struct reftable_table *stack, int n,
+ uint32_t hash_id)
+{
+ struct reftable_merged_table *m = NULL;
+ uint64_t last_max = 0;
+ uint64_t first_min = 0;
+ int i = 0;
+ for (i = 0; i < n; i++) {
+ uint64_t min = reftable_table_min_update_index(&stack[i]);
+ uint64_t max = reftable_table_max_update_index(&stack[i]);
+
+ if (reftable_table_hash_id(&stack[i]) != hash_id) {
+ return REFTABLE_FORMAT_ERROR;
+ }
+ if (i == 0 || min < first_min) {
+ first_min = min;
+ }
+ if (i == 0 || max > last_max) {
+ last_max = max;
+ }
+ }
+
+ m = (struct reftable_merged_table *)reftable_calloc(
+ sizeof(struct reftable_merged_table));
+ m->stack = stack;
+ m->stack_len = n;
+ m->min = first_min;
+ m->max = last_max;
+ m->hash_id = hash_id;
+ *dest = m;
+ return 0;
+}
+
+/* clears the list of subtable, without affecting the readers themselves. */
+void merged_table_release(struct reftable_merged_table *mt)
+{
+ FREE_AND_NULL(mt->stack);
+ mt->stack_len = 0;
+}
+
+void reftable_merged_table_free(struct reftable_merged_table *mt)
+{
+ if (mt == NULL) {
+ return;
+ }
+ merged_table_release(mt);
+ reftable_free(mt);
+}
+
+uint64_t
+reftable_merged_table_max_update_index(struct reftable_merged_table *mt)
+{
+ return mt->max;
+}
+
+uint64_t
+reftable_merged_table_min_update_index(struct reftable_merged_table *mt)
+{
+ return mt->min;
+}
+
+static int reftable_table_seek_record(struct reftable_table *tab,
+ struct reftable_iterator *it,
+ struct reftable_record *rec)
+{
+ return tab->ops->seek_record(tab->table_arg, it, rec);
+}
+
+static int merged_table_seek_record(struct reftable_merged_table *mt,
+ struct reftable_iterator *it,
+ struct reftable_record *rec)
+{
+ struct reftable_iterator *iters = reftable_calloc(
+ sizeof(struct reftable_iterator) * mt->stack_len);
+ struct merged_iter merged = {
+ .stack = iters,
+ .typ = reftable_record_type(rec),
+ .hash_id = mt->hash_id,
+ .suppress_deletions = mt->suppress_deletions,
+ };
+ int n = 0;
+ int err = 0;
+ int i = 0;
+ for (i = 0; i < mt->stack_len && err == 0; i++) {
+ int e = reftable_table_seek_record(&mt->stack[i], &iters[n],
+ rec);
+ if (e < 0) {
+ err = e;
+ }
+ if (e == 0) {
+ n++;
+ }
+ }
+ if (err < 0) {
+ int i = 0;
+ for (i = 0; i < n; i++) {
+ reftable_iterator_destroy(&iters[i]);
+ }
+ reftable_free(iters);
+ return err;
+ }
+
+ merged.stack_len = n;
+ err = merged_iter_init(&merged);
+ if (err < 0) {
+ merged_iter_close(&merged);
+ return err;
+ } else {
+ struct merged_iter *p =
+ reftable_malloc(sizeof(struct merged_iter));
+ *p = merged;
+ iterator_from_merged_iter(it, p);
+ }
+ return 0;
+}
+
+int reftable_merged_table_seek_ref(struct reftable_merged_table *mt,
+ struct reftable_iterator *it,
+ const char *name)
+{
+ struct reftable_ref_record ref = {
+ .refname = (char *)name,
+ };
+ struct reftable_record rec = { NULL };
+ reftable_record_from_ref(&rec, &ref);
+ return merged_table_seek_record(mt, it, &rec);
+}
+
+int reftable_merged_table_seek_log_at(struct reftable_merged_table *mt,
+ struct reftable_iterator *it,
+ const char *name, uint64_t update_index)
+{
+ struct reftable_log_record log = {
+ .refname = (char *)name,
+ .update_index = update_index,
+ };
+ struct reftable_record rec = { NULL };
+ reftable_record_from_log(&rec, &log);
+ return merged_table_seek_record(mt, it, &rec);
+}
+
+int reftable_merged_table_seek_log(struct reftable_merged_table *mt,
+ struct reftable_iterator *it,
+ const char *name)
+{
+ uint64_t max = ~((uint64_t)0);
+ return reftable_merged_table_seek_log_at(mt, it, name, max);
+}
+
+uint32_t reftable_merged_table_hash_id(struct reftable_merged_table *mt)
+{
+ return mt->hash_id;
+}
+
+static int reftable_merged_table_seek_void(void *tab,
+ struct reftable_iterator *it,
+ struct reftable_record *rec)
+{
+ return merged_table_seek_record((struct reftable_merged_table *)tab, it,
+ rec);
+}
+
+static uint32_t reftable_merged_table_hash_id_void(void *tab)
+{
+ return reftable_merged_table_hash_id(
+ (struct reftable_merged_table *)tab);
+}
+
+static uint64_t reftable_merged_table_min_update_index_void(void *tab)
+{
+ return reftable_merged_table_min_update_index(
+ (struct reftable_merged_table *)tab);
+}
+
+static uint64_t reftable_merged_table_max_update_index_void(void *tab)
+{
+ return reftable_merged_table_max_update_index(
+ (struct reftable_merged_table *)tab);
+}
+
+static struct reftable_table_vtable merged_table_vtable = {
+ .seek_record = reftable_merged_table_seek_void,
+ .hash_id = reftable_merged_table_hash_id_void,
+ .min_update_index = reftable_merged_table_min_update_index_void,
+ .max_update_index = reftable_merged_table_max_update_index_void,
+};
+
+void reftable_table_from_merged_table(struct reftable_table *tab,
+ struct reftable_merged_table *merged)
+{
+ assert(tab->ops == NULL);
+ tab->ops = &merged_table_vtable;
+ tab->table_arg = merged;
+}
diff --git a/reftable/merged.h b/reftable/merged.h
new file mode 100644
index 0000000000..8c4d4d58d7
--- /dev/null
+++ b/reftable/merged.h
@@ -0,0 +1,35 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef MERGED_H
+#define MERGED_H
+
+#include "pq.h"
+
+struct reftable_merged_table {
+ struct reftable_table *stack;
+ size_t stack_len;
+ uint32_t hash_id;
+ int suppress_deletions;
+
+ uint64_t min;
+ uint64_t max;
+};
+
+struct merged_iter {
+ struct reftable_iterator *stack;
+ uint32_t hash_id;
+ size_t stack_len;
+ uint8_t typ;
+ int suppress_deletions;
+ struct merged_iter_pqueue pq;
+};
+
+void merged_table_release(struct reftable_merged_table *mt);
+
+#endif
diff --git a/reftable/merged_test.c b/reftable/merged_test.c
new file mode 100644
index 0000000000..fbb2e5ac10
--- /dev/null
+++ b/reftable/merged_test.c
@@ -0,0 +1,333 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "merged.h"
+
+#include "system.h"
+
+#include "basics.h"
+#include "blocksource.h"
+#include "constants.h"
+#include "pq.h"
+#include "reader.h"
+#include "record.h"
+#include "test_framework.h"
+#include "reftable-merged.h"
+#include "reftable-tests.h"
+#include "reftable-generic.h"
+#include "reftable-stack.h"
+
+static void test_pq(void)
+{
+ char *names[54] = { NULL };
+ int N = ARRAY_SIZE(names) - 1;
+
+ struct merged_iter_pqueue pq = { NULL };
+ const char *last = NULL;
+
+ int i = 0;
+ for (i = 0; i < N; i++) {
+ char name[100];
+ snprintf(name, sizeof(name), "%02d", i);
+ names[i] = xstrdup(name);
+ }
+
+ i = 1;
+ do {
+ struct reftable_record rec =
+ reftable_new_record(BLOCK_TYPE_REF);
+ struct pq_entry e = { 0 };
+
+ reftable_record_as_ref(&rec)->refname = names[i];
+ e.rec = rec;
+ merged_iter_pqueue_add(&pq, e);
+ merged_iter_pqueue_check(pq);
+ i = (i * 7) % N;
+ } while (i != 1);
+
+ while (!merged_iter_pqueue_is_empty(pq)) {
+ struct pq_entry e = merged_iter_pqueue_remove(&pq);
+ struct reftable_ref_record *ref =
+ reftable_record_as_ref(&e.rec);
+
+ merged_iter_pqueue_check(pq);
+
+ if (last != NULL) {
+ assert(strcmp(last, ref->refname) < 0);
+ }
+ last = ref->refname;
+ ref->refname = NULL;
+ reftable_free(ref);
+ }
+
+ for (i = 0; i < N; i++) {
+ reftable_free(names[i]);
+ }
+
+ merged_iter_pqueue_release(&pq);
+}
+
+static void write_test_table(struct strbuf *buf,
+ struct reftable_ref_record refs[], int n)
+{
+ int min = 0xffffffff;
+ int max = 0;
+ int i = 0;
+ int err;
+
+ struct reftable_write_options opts = {
+ .block_size = 256,
+ };
+ struct reftable_writer *w = NULL;
+ for (i = 0; i < n; i++) {
+ uint64_t ui = refs[i].update_index;
+ if (ui > max) {
+ max = ui;
+ }
+ if (ui < min) {
+ min = ui;
+ }
+ }
+
+ w = reftable_new_writer(&strbuf_add_void, buf, &opts);
+ reftable_writer_set_limits(w, min, max);
+
+ for (i = 0; i < n; i++) {
+ uint64_t before = refs[i].update_index;
+ int n = reftable_writer_add_ref(w, &refs[i]);
+ assert(n == 0);
+ assert(before == refs[i].update_index);
+ }
+
+ err = reftable_writer_close(w);
+ EXPECT_ERR(err);
+
+ reftable_writer_free(w);
+}
+
+static struct reftable_merged_table *
+merged_table_from_records(struct reftable_ref_record **refs,
+ struct reftable_block_source **source,
+ struct reftable_reader ***readers, int *sizes,
+ struct strbuf *buf, int n)
+{
+ int i = 0;
+ struct reftable_merged_table *mt = NULL;
+ int err;
+ struct reftable_table *tabs =
+ reftable_calloc(n * sizeof(struct reftable_table));
+ *readers = reftable_calloc(n * sizeof(struct reftable_reader *));
+ *source = reftable_calloc(n * sizeof(**source));
+ for (i = 0; i < n; i++) {
+ write_test_table(&buf[i], refs[i], sizes[i]);
+ block_source_from_strbuf(&(*source)[i], &buf[i]);
+
+ err = reftable_new_reader(&(*readers)[i], &(*source)[i],
+ "name");
+ EXPECT_ERR(err);
+ reftable_table_from_reader(&tabs[i], (*readers)[i]);
+ }
+
+ err = reftable_new_merged_table(&mt, tabs, n, SHA1_ID);
+ EXPECT_ERR(err);
+ return mt;
+}
+
+static void readers_destroy(struct reftable_reader **readers, size_t n)
+{
+ int i = 0;
+ for (; i < n; i++)
+ reftable_reader_free(readers[i]);
+ reftable_free(readers);
+}
+
+static void test_merged_between(void)
+{
+ uint8_t hash1[SHA1_SIZE] = { 1, 2, 3, 0 };
+
+ struct reftable_ref_record r1[] = { {
+ .refname = "b",
+ .update_index = 1,
+ .value = hash1,
+ } };
+ struct reftable_ref_record r2[] = { {
+ .refname = "a",
+ .update_index = 2,
+ } };
+
+ struct reftable_ref_record *refs[] = { r1, r2 };
+ int sizes[] = { 1, 1 };
+ struct strbuf bufs[2] = { STRBUF_INIT, STRBUF_INIT };
+ struct reftable_block_source *bs = NULL;
+ struct reftable_reader **readers = NULL;
+ struct reftable_merged_table *mt =
+ merged_table_from_records(refs, &bs, &readers, sizes, bufs, 2);
+ int i;
+ struct reftable_ref_record ref = { NULL };
+ struct reftable_iterator it = { NULL };
+ int err = reftable_merged_table_seek_ref(mt, &it, "a");
+ EXPECT_ERR(err);
+
+ err = reftable_iterator_next_ref(&it, &ref);
+ EXPECT_ERR(err);
+ EXPECT(ref.update_index == 2);
+ reftable_ref_record_release(&ref);
+ reftable_iterator_destroy(&it);
+ readers_destroy(readers, 2);
+ reftable_merged_table_free(mt);
+ for (i = 0; i < ARRAY_SIZE(bufs); i++) {
+ strbuf_release(&bufs[i]);
+ }
+ reftable_free(bs);
+}
+
+static void test_merged(void)
+{
+ uint8_t hash1[SHA1_SIZE] = { 1 };
+ uint8_t hash2[SHA1_SIZE] = { 2 };
+ struct reftable_ref_record r1[] = { {
+ .refname = "a",
+ .update_index = 1,
+ .value = hash1,
+ },
+ {
+ .refname = "b",
+ .update_index = 1,
+ .value = hash1,
+ },
+ {
+ .refname = "c",
+ .update_index = 1,
+ .value = hash1,
+ } };
+ struct reftable_ref_record r2[] = { {
+ .refname = "a",
+ .update_index = 2,
+ } };
+ struct reftable_ref_record r3[] = {
+ {
+ .refname = "c",
+ .update_index = 3,
+ .value = hash2,
+ },
+ {
+ .refname = "d",
+ .update_index = 3,
+ .value = hash1,
+ },
+ };
+
+ struct reftable_ref_record want[] = {
+ r2[0],
+ r1[1],
+ r3[0],
+ r3[1],
+ };
+
+ struct reftable_ref_record *refs[] = { r1, r2, r3 };
+ int sizes[3] = { 3, 1, 2 };
+ struct strbuf bufs[3] = { STRBUF_INIT, STRBUF_INIT, STRBUF_INIT };
+ struct reftable_block_source *bs = NULL;
+ struct reftable_reader **readers = NULL;
+ struct reftable_merged_table *mt =
+ merged_table_from_records(refs, &bs, &readers, sizes, bufs, 3);
+
+ struct reftable_iterator it = { NULL };
+ int err = reftable_merged_table_seek_ref(mt, &it, "a");
+ struct reftable_ref_record *out = NULL;
+ size_t len = 0;
+ size_t cap = 0;
+ int i = 0;
+
+ EXPECT_ERR(err);
+ while (len < 100) { /* cap loops/recursion. */
+ struct reftable_ref_record ref = { NULL };
+ int err = reftable_iterator_next_ref(&it, &ref);
+ if (err > 0) {
+ break;
+ }
+ if (len == cap) {
+ cap = 2 * cap + 1;
+ out = reftable_realloc(
+ out, sizeof(struct reftable_ref_record) * cap);
+ }
+ out[len++] = ref;
+ }
+ reftable_iterator_destroy(&it);
+
+ assert(ARRAY_SIZE(want) == len);
+ for (i = 0; i < len; i++) {
+ assert(reftable_ref_record_equal(&want[i], &out[i], SHA1_SIZE));
+ }
+ for (i = 0; i < len; i++) {
+ reftable_ref_record_release(&out[i]);
+ }
+ reftable_free(out);
+
+ for (i = 0; i < 3; i++) {
+ strbuf_release(&bufs[i]);
+ }
+ readers_destroy(readers, 3);
+ reftable_merged_table_free(mt);
+ reftable_free(bs);
+}
+
+static void test_default_write_opts(void)
+{
+ struct reftable_write_options opts = { 0 };
+ struct strbuf buf = STRBUF_INIT;
+ struct reftable_writer *w =
+ reftable_new_writer(&strbuf_add_void, &buf, &opts);
+
+ struct reftable_ref_record rec = {
+ .refname = "master",
+ .update_index = 1,
+ };
+ int err;
+ struct reftable_block_source source = { NULL };
+ struct reftable_table *tab = reftable_calloc(sizeof(*tab) * 1);
+ uint32_t hash_id;
+ struct reftable_reader *rd = NULL;
+ struct reftable_merged_table *merged = NULL;
+
+ reftable_writer_set_limits(w, 1, 1);
+
+ err = reftable_writer_add_ref(w, &rec);
+ EXPECT_ERR(err);
+
+ err = reftable_writer_close(w);
+ EXPECT_ERR(err);
+ reftable_writer_free(w);
+
+ block_source_from_strbuf(&source, &buf);
+
+ err = reftable_new_reader(&rd, &source, "filename");
+ EXPECT_ERR(err);
+
+ hash_id = reftable_reader_hash_id(rd);
+ assert(hash_id == SHA1_ID);
+
+ reftable_table_from_reader(&tab[0], rd);
+ err = reftable_new_merged_table(&merged, tab, 1, SHA1_ID);
+ EXPECT_ERR(err);
+
+ reftable_reader_free(rd);
+ reftable_merged_table_free(merged);
+ strbuf_release(&buf);
+}
+
+/* XXX test refs_for(oid) */
+
+int merged_test_main(int argc, const char *argv[])
+{
+ test_merged_between();
+ test_pq();
+ test_merged();
+ test_default_write_opts();
+ return 0;
+}
diff --git a/reftable/pq.c b/reftable/pq.c
new file mode 100644
index 0000000000..8918d158e2
--- /dev/null
+++ b/reftable/pq.c
@@ -0,0 +1,115 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "pq.h"
+
+#include "reftable-record.h"
+#include "system.h"
+#include "basics.h"
+
+static int pq_less(struct pq_entry a, struct pq_entry b)
+{
+ struct strbuf ak = STRBUF_INIT;
+ struct strbuf bk = STRBUF_INIT;
+ int cmp = 0;
+ reftable_record_key(&a.rec, &ak);
+ reftable_record_key(&b.rec, &bk);
+
+ cmp = strbuf_cmp(&ak, &bk);
+
+ strbuf_release(&ak);
+ strbuf_release(&bk);
+
+ if (cmp == 0)
+ return a.index > b.index;
+
+ return cmp < 0;
+}
+
+struct pq_entry merged_iter_pqueue_top(struct merged_iter_pqueue pq)
+{
+ return pq.heap[0];
+}
+
+int merged_iter_pqueue_is_empty(struct merged_iter_pqueue pq)
+{
+ return pq.len == 0;
+}
+
+void merged_iter_pqueue_check(struct merged_iter_pqueue pq)
+{
+ int i = 0;
+ for (i = 1; i < pq.len; i++) {
+ int parent = (i - 1) / 2;
+
+ assert(pq_less(pq.heap[parent], pq.heap[i]));
+ }
+}
+
+struct pq_entry merged_iter_pqueue_remove(struct merged_iter_pqueue *pq)
+{
+ int i = 0;
+ struct pq_entry e = pq->heap[0];
+ pq->heap[0] = pq->heap[pq->len - 1];
+ pq->len--;
+
+ i = 0;
+ while (i < pq->len) {
+ int min = i;
+ int j = 2 * i + 1;
+ int k = 2 * i + 2;
+ if (j < pq->len && pq_less(pq->heap[j], pq->heap[i])) {
+ min = j;
+ }
+ if (k < pq->len && pq_less(pq->heap[k], pq->heap[min])) {
+ min = k;
+ }
+
+ if (min == i) {
+ break;
+ }
+
+ SWAP(pq->heap[i], pq->heap[min]);
+ i = min;
+ }
+
+ return e;
+}
+
+void merged_iter_pqueue_add(struct merged_iter_pqueue *pq, struct pq_entry e)
+{
+ int i = 0;
+ if (pq->len == pq->cap) {
+ pq->cap = 2 * pq->cap + 1;
+ pq->heap = reftable_realloc(pq->heap,
+ pq->cap * sizeof(struct pq_entry));
+ }
+
+ pq->heap[pq->len++] = e;
+ i = pq->len - 1;
+ while (i > 0) {
+ int j = (i - 1) / 2;
+ if (pq_less(pq->heap[j], pq->heap[i])) {
+ break;
+ }
+
+ SWAP(pq->heap[j], pq->heap[i]);
+
+ i = j;
+ }
+}
+
+void merged_iter_pqueue_release(struct merged_iter_pqueue *pq)
+{
+ int i = 0;
+ for (i = 0; i < pq->len; i++) {
+ reftable_record_destroy(&pq->heap[i].rec);
+ }
+ FREE_AND_NULL(pq->heap);
+ pq->len = pq->cap = 0;
+}
diff --git a/reftable/pq.h b/reftable/pq.h
new file mode 100644
index 0000000000..385d2fb139
--- /dev/null
+++ b/reftable/pq.h
@@ -0,0 +1,32 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef PQ_H
+#define PQ_H
+
+#include "record.h"
+
+struct pq_entry {
+ int index;
+ struct reftable_record rec;
+};
+
+struct merged_iter_pqueue {
+ struct pq_entry *heap;
+ size_t len;
+ size_t cap;
+};
+
+struct pq_entry merged_iter_pqueue_top(struct merged_iter_pqueue pq);
+int merged_iter_pqueue_is_empty(struct merged_iter_pqueue pq);
+void merged_iter_pqueue_check(struct merged_iter_pqueue pq);
+struct pq_entry merged_iter_pqueue_remove(struct merged_iter_pqueue *pq);
+void merged_iter_pqueue_add(struct merged_iter_pqueue *pq, struct pq_entry e);
+void merged_iter_pqueue_release(struct merged_iter_pqueue *pq);
+
+#endif
diff --git a/reftable/refname.c b/reftable/refname.c
new file mode 100644
index 0000000000..0f4eb3b292
--- /dev/null
+++ b/reftable/refname.c
@@ -0,0 +1,209 @@
+/*
+ Copyright 2020 Google LLC
+
+ Use of this source code is governed by a BSD-style
+ license that can be found in the LICENSE file or at
+ https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "system.h"
+#include "reftable-error.h"
+#include "basics.h"
+#include "refname.h"
+#include "reftable-iterator.h"
+
+struct find_arg {
+ char **names;
+ const char *want;
+};
+
+static int find_name(size_t k, void *arg)
+{
+ struct find_arg *f_arg = (struct find_arg *)arg;
+ return strcmp(f_arg->names[k], f_arg->want) >= 0;
+}
+
+static int modification_has_ref(struct modification *mod, const char *name)
+{
+ struct reftable_ref_record ref = { NULL };
+ int err = 0;
+
+ if (mod->add_len > 0) {
+ struct find_arg arg = {
+ .names = mod->add,
+ .want = name,
+ };
+ int idx = binsearch(mod->add_len, find_name, &arg);
+ if (idx < mod->add_len && !strcmp(mod->add[idx], name)) {
+ return 0;
+ }
+ }
+
+ if (mod->del_len > 0) {
+ struct find_arg arg = {
+ .names = mod->del,
+ .want = name,
+ };
+ int idx = binsearch(mod->del_len, find_name, &arg);
+ if (idx < mod->del_len && !strcmp(mod->del[idx], name)) {
+ return 1;
+ }
+ }
+
+ err = reftable_table_read_ref(&mod->tab, name, &ref);
+ reftable_ref_record_release(&ref);
+ return err;
+}
+
+static void modification_release(struct modification *mod)
+{
+ /* don't delete the strings themselves; they're owned by ref records.
+ */
+ FREE_AND_NULL(mod->add);
+ FREE_AND_NULL(mod->del);
+ mod->add_len = 0;
+ mod->del_len = 0;
+}
+
+static int modification_has_ref_with_prefix(struct modification *mod,
+ const char *prefix)
+{
+ struct reftable_iterator it = { NULL };
+ struct reftable_ref_record ref = { NULL };
+ int err = 0;
+
+ if (mod->add_len > 0) {
+ struct find_arg arg = {
+ .names = mod->add,
+ .want = prefix,
+ };
+ int idx = binsearch(mod->add_len, find_name, &arg);
+ if (idx < mod->add_len &&
+ !strncmp(prefix, mod->add[idx], strlen(prefix)))
+ goto done;
+ }
+ err = reftable_table_seek_ref(&mod->tab, &it, prefix);
+ if (err)
+ goto done;
+
+ while (1) {
+ err = reftable_iterator_next_ref(&it, &ref);
+ if (err)
+ goto done;
+
+ if (mod->del_len > 0) {
+ struct find_arg arg = {
+ .names = mod->del,
+ .want = ref.refname,
+ };
+ int idx = binsearch(mod->del_len, find_name, &arg);
+ if (idx < mod->del_len &&
+ !strcmp(ref.refname, mod->del[idx])) {
+ continue;
+ }
+ }
+
+ if (strncmp(ref.refname, prefix, strlen(prefix))) {
+ err = 1;
+ goto done;
+ }
+ err = 0;
+ goto done;
+ }
+
+done:
+ reftable_ref_record_release(&ref);
+ reftable_iterator_destroy(&it);
+ return err;
+}
+
+static int validate_refname(const char *name)
+{
+ while (1) {
+ char *next = strchr(name, '/');
+ if (!*name) {
+ return REFTABLE_REFNAME_ERROR;
+ }
+ if (!next) {
+ return 0;
+ }
+ if (next - name == 0 || (next - name == 1 && *name == '.') ||
+ (next - name == 2 && name[0] == '.' && name[1] == '.'))
+ return REFTABLE_REFNAME_ERROR;
+ name = next + 1;
+ }
+ return 0;
+}
+
+int validate_ref_record_addition(struct reftable_table tab,
+ struct reftable_ref_record *recs, size_t sz)
+{
+ struct modification mod = {
+ .tab = tab,
+ .add = reftable_calloc(sizeof(char *) * sz),
+ .del = reftable_calloc(sizeof(char *) * sz),
+ };
+ int i = 0;
+ int err = 0;
+ for (; i < sz; i++) {
+ if (reftable_ref_record_is_deletion(&recs[i])) {
+ mod.del[mod.del_len++] = recs[i].refname;
+ } else {
+ mod.add[mod.add_len++] = recs[i].refname;
+ }
+ }
+
+ err = modification_validate(&mod);
+ modification_release(&mod);
+ return err;
+}
+
+static void strbuf_trim_component(struct strbuf *sl)
+{
+ while (sl->len > 0) {
+ int is_slash = (sl->buf[sl->len - 1] == '/');
+ strbuf_setlen(sl, sl->len - 1);
+ if (is_slash)
+ break;
+ }
+}
+
+int modification_validate(struct modification *mod)
+{
+ struct strbuf slashed = STRBUF_INIT;
+ int err = 0;
+ int i = 0;
+ for (; i < mod->add_len; i++) {
+ err = validate_refname(mod->add[i]);
+ if (err)
+ goto done;
+ strbuf_reset(&slashed);
+ strbuf_addstr(&slashed, mod->add[i]);
+ strbuf_addstr(&slashed, "/");
+
+ err = modification_has_ref_with_prefix(mod, slashed.buf);
+ if (err == 0) {
+ err = REFTABLE_NAME_CONFLICT;
+ goto done;
+ }
+ if (err < 0)
+ goto done;
+
+ strbuf_reset(&slashed);
+ strbuf_addstr(&slashed, mod->add[i]);
+ while (slashed.len) {
+ strbuf_trim_component(&slashed);
+ err = modification_has_ref(mod, slashed.buf);
+ if (err == 0) {
+ err = REFTABLE_NAME_CONFLICT;
+ goto done;
+ }
+ if (err < 0)
+ goto done;
+ }
+ }
+ err = 0;
+done:
+ strbuf_release(&slashed);
+ return err;
+}
diff --git a/reftable/refname.h b/reftable/refname.h
new file mode 100644
index 0000000000..a24b40fcb4
--- /dev/null
+++ b/reftable/refname.h
@@ -0,0 +1,29 @@
+/*
+ Copyright 2020 Google LLC
+
+ Use of this source code is governed by a BSD-style
+ license that can be found in the LICENSE file or at
+ https://developers.google.com/open-source/licenses/bsd
+*/
+#ifndef REFNAME_H
+#define REFNAME_H
+
+#include "reftable-record.h"
+#include "reftable-generic.h"
+
+struct modification {
+ struct reftable_table tab;
+
+ char **add;
+ size_t add_len;
+
+ char **del;
+ size_t del_len;
+};
+
+int validate_ref_record_addition(struct reftable_table tab,
+ struct reftable_ref_record *recs, size_t sz);
+
+int modification_validate(struct modification *mod);
+
+#endif
diff --git a/reftable/refname_test.c b/reftable/refname_test.c
new file mode 100644
index 0000000000..af04bc9a59
--- /dev/null
+++ b/reftable/refname_test.c
@@ -0,0 +1,100 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "basics.h"
+#include "block.h"
+#include "blocksource.h"
+#include "constants.h"
+#include "reader.h"
+#include "record.h"
+#include "refname.h"
+#include "reftable-error.h"
+#include "reftable-writer.h"
+#include "system.h"
+
+#include "test_framework.h"
+#include "reftable-tests.h"
+
+struct testcase {
+ char *add;
+ char *del;
+ int error_code;
+};
+
+static void test_conflict(void)
+{
+ struct reftable_write_options opts = { 0 };
+ struct strbuf buf = STRBUF_INIT;
+ struct reftable_writer *w =
+ reftable_new_writer(&strbuf_add_void, &buf, &opts);
+ struct reftable_ref_record rec = {
+ .refname = "a/b",
+ .target = "destination", /* make sure it's not a symref. */
+ .update_index = 1,
+ };
+ int err;
+ int i;
+ struct reftable_block_source source = { NULL };
+ struct reftable_reader *rd = NULL;
+ struct reftable_table tab = { NULL };
+ struct testcase cases[] = {
+ { "a/b/c", NULL, REFTABLE_NAME_CONFLICT },
+ { "b", NULL, 0 },
+ { "a", NULL, REFTABLE_NAME_CONFLICT },
+ { "a", "a/b", 0 },
+
+ { "p/", NULL, REFTABLE_REFNAME_ERROR },
+ { "p//q", NULL, REFTABLE_REFNAME_ERROR },
+ { "p/./q", NULL, REFTABLE_REFNAME_ERROR },
+ { "p/../q", NULL, REFTABLE_REFNAME_ERROR },
+
+ { "a/b/c", "a/b", 0 },
+ { NULL, "a//b", 0 },
+ };
+ reftable_writer_set_limits(w, 1, 1);
+
+ err = reftable_writer_add_ref(w, &rec);
+ EXPECT_ERR(err);
+
+ err = reftable_writer_close(w);
+ EXPECT_ERR(err);
+ reftable_writer_free(w);
+
+ block_source_from_strbuf(&source, &buf);
+ err = reftable_new_reader(&rd, &source, "filename");
+ EXPECT_ERR(err);
+
+ reftable_table_from_reader(&tab, rd);
+
+ for (i = 0; i < ARRAY_SIZE(cases); i++) {
+ struct modification mod = {
+ .tab = tab,
+ };
+
+ if (cases[i].add != NULL) {
+ mod.add = &cases[i].add;
+ mod.add_len = 1;
+ }
+ if (cases[i].del != NULL) {
+ mod.del = &cases[i].del;
+ mod.del_len = 1;
+ }
+
+ err = modification_validate(&mod);
+ EXPECT(err == cases[i].error_code);
+ }
+
+ reftable_reader_free(rd);
+ strbuf_release(&buf);
+}
+
+int refname_test_main(int argc, const char *argv[])
+{
+ test_conflict();
+ return 0;
+}
diff --git a/reftable/reftable-generic.h b/reftable/reftable-generic.h
new file mode 100644
index 0000000000..964d25f040
--- /dev/null
+++ b/reftable/reftable-generic.h
@@ -0,0 +1,49 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef REFTABLE_GENERIC_H
+#define REFTABLE_GENERIC_H
+
+#include "reftable-iterator.h"
+#include "reftable-reader.h"
+#include "reftable-merged.h"
+
+/*
+ Provides a unified API for reading tables, either merged tables, or single
+ readers.
+*/
+struct reftable_table {
+ struct reftable_table_vtable *ops;
+ void *table_arg;
+};
+
+int reftable_table_seek_ref(struct reftable_table *tab,
+ struct reftable_iterator *it, const char *name);
+
+void reftable_table_from_reader(struct reftable_table *tab,
+ struct reftable_reader *reader);
+
+/* returns the hash ID from a generic reftable_table */
+uint32_t reftable_table_hash_id(struct reftable_table *tab);
+
+/* create a generic table from reftable_merged_table */
+void reftable_table_from_merged_table(struct reftable_table *tab,
+ struct reftable_merged_table *table);
+
+/* returns the max update_index covered by this table. */
+uint64_t reftable_table_max_update_index(struct reftable_table *tab);
+
+/* returns the min update_index covered by this table. */
+uint64_t reftable_table_min_update_index(struct reftable_table *tab);
+
+/* convenience function to read a single ref. Returns < 0 for error, 0
+ for success, and 1 if ref not found. */
+int reftable_table_read_ref(struct reftable_table *tab, const char *name,
+ struct reftable_ref_record *ref);
+
+#endif
diff --git a/reftable/reftable-merged.h b/reftable/reftable-merged.h
new file mode 100644
index 0000000000..5ee16aa02a
--- /dev/null
+++ b/reftable/reftable-merged.h
@@ -0,0 +1,68 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef REFTABLE_MERGED_H
+#define REFTABLE_MERGED_H
+
+#include "reftable-iterator.h"
+
+/*
+ Merged tables
+
+ A ref database kept in a sequence of table files. The merged_table presents a
+ unified view to reading (seeking, iterating) a sequence of immutable tables.
+
+ The merged tables are on purpose kept disconnected from their actual storage
+ (eg. files on disk), because it is useful to merge tables aren't files. For
+ example, the per-workspace and global ref namespace can be implemented as a
+ merged table of two stacks of file-backed reftables.
+*/
+
+/* A merged table is implements seeking/iterating over a stack of tables. */
+struct reftable_merged_table;
+
+/* A generic reftable; see below. */
+struct reftable_table;
+
+/* reftable_new_merged_table creates a new merged table. It takes ownership of
+ the stack array.
+*/
+int reftable_new_merged_table(struct reftable_merged_table **dest,
+ struct reftable_table *stack, int n,
+ uint32_t hash_id);
+
+/* returns an iterator positioned just before 'name' */
+int reftable_merged_table_seek_ref(struct reftable_merged_table *mt,
+ struct reftable_iterator *it,
+ const char *name);
+
+/* returns an iterator for log entry, at given update_index */
+int reftable_merged_table_seek_log_at(struct reftable_merged_table *mt,
+ struct reftable_iterator *it,
+ const char *name, uint64_t update_index);
+
+/* like reftable_merged_table_seek_log_at but look for the newest entry. */
+int reftable_merged_table_seek_log(struct reftable_merged_table *mt,
+ struct reftable_iterator *it,
+ const char *name);
+
+/* returns the max update_index covered by this merged table. */
+uint64_t
+reftable_merged_table_max_update_index(struct reftable_merged_table *mt);
+
+/* returns the min update_index covered by this merged table. */
+uint64_t
+reftable_merged_table_min_update_index(struct reftable_merged_table *mt);
+
+/* releases memory for the merged_table */
+void reftable_merged_table_free(struct reftable_merged_table *m);
+
+/* return the hash ID of the merged table. */
+uint32_t reftable_merged_table_hash_id(struct reftable_merged_table *m);
+
+#endif
diff --git a/reftable/reftable-stack.h b/reftable/reftable-stack.h
new file mode 100644
index 0000000000..140a28b790
--- /dev/null
+++ b/reftable/reftable-stack.h
@@ -0,0 +1,116 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef REFTABLE_STACK_H
+#define REFTABLE_STACK_H
+
+#include "reftable-writer.h"
+
+/*
+ The stack presents an interface to a mutable sequence of reftables.
+
+ A stack can be mutated by pushing a table to the top of the stack.
+
+ The reftable_stack automatically compacts files on disk to ensure good
+ amortized performance.
+*/
+struct reftable_stack;
+
+/* open a new reftable stack. The tables along with the table list will be
+ stored in 'dir'. Typically, this should be .git/reftables.
+*/
+int reftable_new_stack(struct reftable_stack **dest, const char *dir,
+ struct reftable_write_options config);
+
+/* returns the update_index at which a next table should be written. */
+uint64_t reftable_stack_next_update_index(struct reftable_stack *st);
+
+/* holds a transaction to add tables at the top of a stack. */
+struct reftable_addition;
+
+/*
+ returns a new transaction to add reftables to the given stack. As a side
+ effect, the ref database is locked.
+*/
+int reftable_stack_new_addition(struct reftable_addition **dest,
+ struct reftable_stack *st);
+
+/* Adds a reftable to transaction. */
+int reftable_addition_add(struct reftable_addition *add,
+ int (*write_table)(struct reftable_writer *wr,
+ void *arg),
+ void *arg);
+
+/* Commits the transaction, releasing the lock. */
+int reftable_addition_commit(struct reftable_addition *add);
+
+/* Release all non-committed data from the transaction, and deallocate the
+ transaction. Releases the lock if held. */
+void reftable_addition_destroy(struct reftable_addition *add);
+
+/* add a new table to the stack. The write_table function must call
+ reftable_writer_set_limits, add refs and return an error value. */
+int reftable_stack_add(struct reftable_stack *st,
+ int (*write_table)(struct reftable_writer *wr,
+ void *write_arg),
+ void *write_arg);
+
+/* returns the merged_table for seeking. This table is valid until the
+ next write or reload, and should not be closed or deleted.
+*/
+struct reftable_merged_table *
+reftable_stack_merged_table(struct reftable_stack *st);
+
+/* frees all resources associated with the stack. */
+void reftable_stack_destroy(struct reftable_stack *st);
+
+/* Reloads the stack if necessary. This is very cheap to run if the stack was up
+ * to date */
+int reftable_stack_reload(struct reftable_stack *st);
+
+/* Policy for expiring reflog entries. */
+struct reftable_log_expiry_config {
+ /* Drop entries older than this timestamp */
+ uint64_t time;
+
+ /* Drop older entries */
+ uint64_t min_update_index;
+};
+
+/* compacts all reftables into a giant table. Expire reflog entries if config is
+ * non-NULL */
+int reftable_stack_compact_all(struct reftable_stack *st,
+ struct reftable_log_expiry_config *config);
+
+/* heuristically compact unbalanced table stack. */
+int reftable_stack_auto_compact(struct reftable_stack *st);
+
+/* convenience function to read a single ref. Returns < 0 for error, 0
+ for success, and 1 if ref not found. */
+int reftable_stack_read_ref(struct reftable_stack *st, const char *refname,
+ struct reftable_ref_record *ref);
+
+/* convenience function to read a single log. Returns < 0 for error, 0
+ for success, and 1 if ref not found. */
+int reftable_stack_read_log(struct reftable_stack *st, const char *refname,
+ struct reftable_log_record *log);
+
+/* statistics on past compactions. */
+struct reftable_compaction_stats {
+ uint64_t bytes; /* total number of bytes written */
+ uint64_t entries_written; /* total number of entries written, including
+ failures. */
+ int attempts; /* how often we tried to compact */
+ int failures; /* failures happen on concurrent updates */
+};
+
+/* return statistics for compaction up till now. */
+struct reftable_compaction_stats *
+reftable_stack_compaction_stats(struct reftable_stack *st);
+
+#endif
diff --git a/reftable/reftable.c b/reftable/reftable.c
new file mode 100644
index 0000000000..dc4fd03d5b
--- /dev/null
+++ b/reftable/reftable.c
@@ -0,0 +1,98 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "record.h"
+#include "reader.h"
+#include "reftable-iterator.h"
+#include "reftable-generic.h"
+
+static int reftable_reader_seek_void(void *tab, struct reftable_iterator *it,
+ struct reftable_record *rec)
+{
+ return reader_seek((struct reftable_reader *)tab, it, rec);
+}
+
+static uint32_t reftable_reader_hash_id_void(void *tab)
+{
+ return reftable_reader_hash_id((struct reftable_reader *)tab);
+}
+
+static uint64_t reftable_reader_min_update_index_void(void *tab)
+{
+ return reftable_reader_min_update_index((struct reftable_reader *)tab);
+}
+
+static uint64_t reftable_reader_max_update_index_void(void *tab)
+{
+ return reftable_reader_max_update_index((struct reftable_reader *)tab);
+}
+
+static struct reftable_table_vtable reader_vtable = {
+ .seek_record = reftable_reader_seek_void,
+ .hash_id = reftable_reader_hash_id_void,
+ .min_update_index = reftable_reader_min_update_index_void,
+ .max_update_index = reftable_reader_max_update_index_void,
+};
+
+int reftable_table_seek_ref(struct reftable_table *tab,
+ struct reftable_iterator *it, const char *name)
+{
+ struct reftable_ref_record ref = {
+ .refname = (char *)name,
+ };
+ struct reftable_record rec = { NULL };
+ reftable_record_from_ref(&rec, &ref);
+ return tab->ops->seek_record(tab->table_arg, it, &rec);
+}
+
+void reftable_table_from_reader(struct reftable_table *tab,
+ struct reftable_reader *reader)
+{
+ assert(tab->ops == NULL);
+ tab->ops = &reader_vtable;
+ tab->table_arg = reader;
+}
+
+int reftable_table_read_ref(struct reftable_table *tab, const char *name,
+ struct reftable_ref_record *ref)
+{
+ struct reftable_iterator it = { NULL };
+ int err = reftable_table_seek_ref(tab, &it, name);
+ if (err)
+ goto done;
+
+ err = reftable_iterator_next_ref(&it, ref);
+ if (err)
+ goto done;
+
+ if (strcmp(ref->refname, name) ||
+ reftable_ref_record_is_deletion(ref)) {
+ reftable_ref_record_release(ref);
+ err = 1;
+ goto done;
+ }
+
+done:
+ reftable_iterator_destroy(&it);
+ return err;
+}
+
+uint64_t reftable_table_max_update_index(struct reftable_table *tab)
+{
+ return tab->ops->max_update_index(tab->table_arg);
+}
+
+uint64_t reftable_table_min_update_index(struct reftable_table *tab)
+{
+ return tab->ops->min_update_index(tab->table_arg);
+}
+
+uint32_t reftable_table_hash_id(struct reftable_table *tab)
+{
+ return tab->ops->hash_id(tab->table_arg);
+}
diff --git a/reftable/stack.c b/reftable/stack.c
new file mode 100644
index 0000000000..1d632937d7
--- /dev/null
+++ b/reftable/stack.c
@@ -0,0 +1,1247 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "stack.h"
+
+#include "system.h"
+#include "merged.h"
+#include "reader.h"
+#include "refname.h"
+#include "reftable-error.h"
+#include "reftable-record.h"
+#include "writer.h"
+
+static int stack_try_add(struct reftable_stack *st,
+ int (*write_table)(struct reftable_writer *wr,
+ void *arg),
+ void *arg);
+static int stack_write_compact(struct reftable_stack *st,
+ struct reftable_writer *wr, int first, int last,
+ struct reftable_log_expiry_config *config);
+static int stack_check_addition(struct reftable_stack *st,
+ const char *new_tab_name);
+static void reftable_addition_close(struct reftable_addition *add);
+static int reftable_stack_reload_maybe_reuse(struct reftable_stack *st,
+ int reuse_open);
+
+static int reftable_fd_write(void *arg, const void *data, size_t sz)
+{
+ int *fdp = (int *)arg;
+ return write(*fdp, data, sz);
+}
+
+int reftable_new_stack(struct reftable_stack **dest, const char *dir,
+ struct reftable_write_options config)
+{
+ struct reftable_stack *p =
+ reftable_calloc(sizeof(struct reftable_stack));
+ struct strbuf list_file_name = STRBUF_INIT;
+ int err = 0;
+
+ if (config.hash_id == 0) {
+ config.hash_id = SHA1_ID;
+ }
+
+ *dest = NULL;
+
+ strbuf_reset(&list_file_name);
+ strbuf_addstr(&list_file_name, dir);
+ strbuf_addstr(&list_file_name, "/tables.list");
+
+ p->list_file = strbuf_detach(&list_file_name, NULL);
+ p->reftable_dir = xstrdup(dir);
+ p->config = config;
+
+ err = reftable_stack_reload_maybe_reuse(p, 1);
+ if (err < 0) {
+ reftable_stack_destroy(p);
+ } else {
+ *dest = p;
+ }
+ return err;
+}
+
+static int fd_read_lines(int fd, char ***namesp)
+{
+ off_t size = lseek(fd, 0, SEEK_END);
+ char *buf = NULL;
+ int err = 0;
+ if (size < 0) {
+ err = REFTABLE_IO_ERROR;
+ goto done;
+ }
+ err = lseek(fd, 0, SEEK_SET);
+ if (err < 0) {
+ err = REFTABLE_IO_ERROR;
+ goto done;
+ }
+
+ buf = reftable_malloc(size + 1);
+ if (read(fd, buf, size) != size) {
+ err = REFTABLE_IO_ERROR;
+ goto done;
+ }
+ buf[size] = 0;
+
+ parse_names(buf, size, namesp);
+
+done:
+ reftable_free(buf);
+ return err;
+}
+
+int read_lines(const char *filename, char ***namesp)
+{
+ int fd = open(filename, O_RDONLY, 0644);
+ int err = 0;
+ if (fd < 0) {
+ if (errno == ENOENT) {
+ *namesp = reftable_calloc(sizeof(char *));
+ return 0;
+ }
+
+ return REFTABLE_IO_ERROR;
+ }
+ err = fd_read_lines(fd, namesp);
+ close(fd);
+ return err;
+}
+
+struct reftable_merged_table *
+reftable_stack_merged_table(struct reftable_stack *st)
+{
+ return st->merged;
+}
+
+/* Close and free the stack */
+void reftable_stack_destroy(struct reftable_stack *st)
+{
+ if (st->merged != NULL) {
+ reftable_merged_table_free(st->merged);
+ st->merged = NULL;
+ }
+
+ if (st->readers != NULL) {
+ int i = 0;
+ for (i = 0; i < st->readers_len; i++) {
+ reftable_reader_free(st->readers[i]);
+ }
+ st->readers_len = 0;
+ FREE_AND_NULL(st->readers);
+ }
+ FREE_AND_NULL(st->list_file);
+ FREE_AND_NULL(st->reftable_dir);
+ reftable_free(st);
+}
+
+static struct reftable_reader **stack_copy_readers(struct reftable_stack *st,
+ int cur_len)
+{
+ struct reftable_reader **cur =
+ reftable_calloc(sizeof(struct reftable_reader *) * cur_len);
+ int i = 0;
+ for (i = 0; i < cur_len; i++) {
+ cur[i] = st->readers[i];
+ }
+ return cur;
+}
+
+static int reftable_stack_reload_once(struct reftable_stack *st, char **names,
+ int reuse_open)
+{
+ int cur_len = st->merged == NULL ? 0 : st->merged->stack_len;
+ struct reftable_reader **cur = stack_copy_readers(st, cur_len);
+ int err = 0;
+ int names_len = names_length(names);
+ struct reftable_reader **new_readers =
+ reftable_calloc(sizeof(struct reftable_reader *) * names_len);
+ struct reftable_table *new_tables =
+ reftable_calloc(sizeof(struct reftable_table) * names_len);
+ int new_readers_len = 0;
+ struct reftable_merged_table *new_merged = NULL;
+ int i;
+
+ while (*names) {
+ struct reftable_reader *rd = NULL;
+ char *name = *names++;
+
+ /* this is linear; we assume compaction keeps the number of
+ tables under control so this is not quadratic. */
+ int j = 0;
+ for (j = 0; reuse_open && j < cur_len; j++) {
+ if (cur[j] != NULL && 0 == strcmp(cur[j]->name, name)) {
+ rd = cur[j];
+ cur[j] = NULL;
+ break;
+ }
+ }
+
+ if (rd == NULL) {
+ struct reftable_block_source src = { NULL };
+ struct strbuf table_path = STRBUF_INIT;
+ strbuf_addstr(&table_path, st->reftable_dir);
+ strbuf_addstr(&table_path, "/");
+ strbuf_addstr(&table_path, name);
+
+ err = reftable_block_source_from_file(&src,
+ table_path.buf);
+ strbuf_release(&table_path);
+
+ if (err < 0)
+ goto done;
+
+ err = reftable_new_reader(&rd, &src, name);
+ if (err < 0)
+ goto done;
+ }
+
+ new_readers[new_readers_len] = rd;
+ reftable_table_from_reader(&new_tables[new_readers_len], rd);
+ new_readers_len++;
+ }
+
+ /* success! */
+ err = reftable_new_merged_table(&new_merged, new_tables,
+ new_readers_len, st->config.hash_id);
+ if (err < 0)
+ goto done;
+
+ new_tables = NULL;
+ st->readers_len = new_readers_len;
+ if (st->merged != NULL) {
+ merged_table_release(st->merged);
+ reftable_merged_table_free(st->merged);
+ }
+ if (st->readers != NULL) {
+ reftable_free(st->readers);
+ }
+ st->readers = new_readers;
+ new_readers = NULL;
+ new_readers_len = 0;
+
+ new_merged->suppress_deletions = 1;
+ st->merged = new_merged;
+ for (i = 0; i < cur_len; i++) {
+ if (cur[i] != NULL) {
+ reader_close(cur[i]);
+ reftable_reader_free(cur[i]);
+ }
+ }
+
+done:
+ for (i = 0; i < new_readers_len; i++) {
+ reader_close(new_readers[i]);
+ reftable_reader_free(new_readers[i]);
+ }
+ reftable_free(new_readers);
+ reftable_free(new_tables);
+ reftable_free(cur);
+ return err;
+}
+
+/* return negative if a before b. */
+static int tv_cmp(struct timeval *a, struct timeval *b)
+{
+ time_t diff = a->tv_sec - b->tv_sec;
+ int udiff = a->tv_usec - b->tv_usec;
+
+ if (diff != 0)
+ return diff;
+
+ return udiff;
+}
+
+static int reftable_stack_reload_maybe_reuse(struct reftable_stack *st,
+ int reuse_open)
+{
+ struct timeval deadline = { 0 };
+ int err = gettimeofday(&deadline, NULL);
+ int64_t delay = 0;
+ int tries = 0;
+ if (err < 0)
+ return err;
+
+ deadline.tv_sec += 3;
+ while (1) {
+ char **names = NULL;
+ char **names_after = NULL;
+ struct timeval now = { 0 };
+ int err = gettimeofday(&now, NULL);
+ int err2 = 0;
+ if (err < 0) {
+ return err;
+ }
+
+ /* Only look at deadlines after the first few times. This
+ simplifies debugging in GDB */
+ tries++;
+ if (tries > 3 && tv_cmp(&now, &deadline) >= 0) {
+ break;
+ }
+
+ err = read_lines(st->list_file, &names);
+ if (err < 0) {
+ free_names(names);
+ return err;
+ }
+ err = reftable_stack_reload_once(st, names, reuse_open);
+ if (err == 0) {
+ free_names(names);
+ break;
+ }
+ if (err != REFTABLE_NOT_EXIST_ERROR) {
+ free_names(names);
+ return err;
+ }
+
+ /* err == REFTABLE_NOT_EXIST_ERROR can be caused by a concurrent
+ writer. Check if there was one by checking if the name list
+ changed.
+ */
+ err2 = read_lines(st->list_file, &names_after);
+ if (err2 < 0) {
+ free_names(names);
+ return err2;
+ }
+
+ if (names_equal(names_after, names)) {
+ free_names(names);
+ free_names(names_after);
+ return err;
+ }
+ free_names(names);
+ free_names(names_after);
+
+ delay = delay + (delay * rand()) / RAND_MAX + 1;
+ sleep_millisec(delay);
+ }
+
+ return 0;
+}
+
+/* -1 = error
+ 0 = up to date
+ 1 = changed. */
+static int stack_uptodate(struct reftable_stack *st)
+{
+ char **names = NULL;
+ int err = read_lines(st->list_file, &names);
+ int i = 0;
+ if (err < 0)
+ return err;
+
+ for (i = 0; i < st->readers_len; i++) {
+ if (names[i] == NULL) {
+ err = 1;
+ goto done;
+ }
+
+ if (strcmp(st->readers[i]->name, names[i])) {
+ err = 1;
+ goto done;
+ }
+ }
+
+ if (names[st->merged->stack_len] != NULL) {
+ err = 1;
+ goto done;
+ }
+
+done:
+ free_names(names);
+ return err;
+}
+
+int reftable_stack_reload(struct reftable_stack *st)
+{
+ int err = stack_uptodate(st);
+ if (err > 0)
+ return reftable_stack_reload_maybe_reuse(st, 1);
+ return err;
+}
+
+int reftable_stack_add(struct reftable_stack *st,
+ int (*write)(struct reftable_writer *wr, void *arg),
+ void *arg)
+{
+ int err = stack_try_add(st, write, arg);
+ if (err < 0) {
+ if (err == REFTABLE_LOCK_ERROR) {
+ /* Ignore error return, we want to propagate
+ REFTABLE_LOCK_ERROR.
+ */
+ reftable_stack_reload(st);
+ }
+ return err;
+ }
+
+ if (!st->disable_auto_compact)
+ return reftable_stack_auto_compact(st);
+
+ return 0;
+}
+
+static void format_name(struct strbuf *dest, uint64_t min, uint64_t max)
+{
+ char buf[100];
+ snprintf(buf, sizeof(buf), "0x%012" PRIx64 "-0x%012" PRIx64, min, max);
+ strbuf_reset(dest);
+ strbuf_addstr(dest, buf);
+}
+
+struct reftable_addition {
+ int lock_file_fd;
+ struct strbuf lock_file_name;
+ struct reftable_stack *stack;
+ char **names;
+ char **new_tables;
+ int new_tables_len;
+ uint64_t next_update_index;
+};
+
+#define REFTABLE_ADDITION_INIT \
+ { \
+ .lock_file_name = STRBUF_INIT \
+ }
+
+static int reftable_stack_init_addition(struct reftable_addition *add,
+ struct reftable_stack *st)
+{
+ int err = 0;
+ add->stack = st;
+
+ strbuf_reset(&add->lock_file_name);
+ strbuf_addstr(&add->lock_file_name, st->list_file);
+ strbuf_addstr(&add->lock_file_name, ".lock");
+
+ add->lock_file_fd = open(add->lock_file_name.buf,
+ O_EXCL | O_CREAT | O_WRONLY, 0644);
+ if (add->lock_file_fd < 0) {
+ if (errno == EEXIST) {
+ err = REFTABLE_LOCK_ERROR;
+ } else {
+ err = REFTABLE_IO_ERROR;
+ }
+ goto done;
+ }
+ err = stack_uptodate(st);
+ if (err < 0)
+ goto done;
+
+ if (err > 1) {
+ err = REFTABLE_LOCK_ERROR;
+ goto done;
+ }
+
+ add->next_update_index = reftable_stack_next_update_index(st);
+done:
+ if (err) {
+ reftable_addition_close(add);
+ }
+ return err;
+}
+
+static void reftable_addition_close(struct reftable_addition *add)
+{
+ int i = 0;
+ struct strbuf nm = STRBUF_INIT;
+ for (i = 0; i < add->new_tables_len; i++) {
+ strbuf_reset(&nm);
+ strbuf_addstr(&nm, add->stack->list_file);
+ strbuf_addstr(&nm, "/");
+ strbuf_addstr(&nm, add->new_tables[i]);
+ unlink(nm.buf);
+ reftable_free(add->new_tables[i]);
+ add->new_tables[i] = NULL;
+ }
+ reftable_free(add->new_tables);
+ add->new_tables = NULL;
+ add->new_tables_len = 0;
+
+ if (add->lock_file_fd > 0) {
+ close(add->lock_file_fd);
+ add->lock_file_fd = 0;
+ }
+ if (add->lock_file_name.len > 0) {
+ unlink(add->lock_file_name.buf);
+ strbuf_release(&add->lock_file_name);
+ }
+
+ free_names(add->names);
+ add->names = NULL;
+ strbuf_release(&nm);
+}
+
+void reftable_addition_destroy(struct reftable_addition *add)
+{
+ if (add == NULL) {
+ return;
+ }
+ reftable_addition_close(add);
+ reftable_free(add);
+}
+
+int reftable_addition_commit(struct reftable_addition *add)
+{
+ struct strbuf table_list = STRBUF_INIT;
+ int i = 0;
+ int err = 0;
+ if (add->new_tables_len == 0)
+ goto done;
+
+ for (i = 0; i < add->stack->merged->stack_len; i++) {
+ strbuf_addstr(&table_list, add->stack->readers[i]->name);
+ strbuf_addstr(&table_list, "\n");
+ }
+ for (i = 0; i < add->new_tables_len; i++) {
+ strbuf_addstr(&table_list, add->new_tables[i]);
+ strbuf_addstr(&table_list, "\n");
+ }
+
+ err = write(add->lock_file_fd, table_list.buf, table_list.len);
+ strbuf_release(&table_list);
+ if (err < 0) {
+ err = REFTABLE_IO_ERROR;
+ goto done;
+ }
+
+ err = close(add->lock_file_fd);
+ add->lock_file_fd = 0;
+ if (err < 0) {
+ err = REFTABLE_IO_ERROR;
+ goto done;
+ }
+
+ err = rename(add->lock_file_name.buf, add->stack->list_file);
+ if (err < 0) {
+ err = REFTABLE_IO_ERROR;
+ goto done;
+ }
+
+ err = reftable_stack_reload(add->stack);
+
+done:
+ reftable_addition_close(add);
+ return err;
+}
+
+int reftable_stack_new_addition(struct reftable_addition **dest,
+ struct reftable_stack *st)
+{
+ int err = 0;
+ struct reftable_addition empty = REFTABLE_ADDITION_INIT;
+ *dest = reftable_calloc(sizeof(**dest));
+ **dest = empty;
+ err = reftable_stack_init_addition(*dest, st);
+ if (err) {
+ reftable_free(*dest);
+ *dest = NULL;
+ }
+ return err;
+}
+
+static int stack_try_add(struct reftable_stack *st,
+ int (*write_table)(struct reftable_writer *wr,
+ void *arg),
+ void *arg)
+{
+ struct reftable_addition add = REFTABLE_ADDITION_INIT;
+ int err = reftable_stack_init_addition(&add, st);
+ if (err < 0)
+ goto done;
+ if (err > 0) {
+ err = REFTABLE_LOCK_ERROR;
+ goto done;
+ }
+
+ err = reftable_addition_add(&add, write_table, arg);
+ if (err < 0)
+ goto done;
+
+ err = reftable_addition_commit(&add);
+done:
+ reftable_addition_close(&add);
+ return err;
+}
+
+int reftable_addition_add(struct reftable_addition *add,
+ int (*write_table)(struct reftable_writer *wr,
+ void *arg),
+ void *arg)
+{
+ struct strbuf temp_tab_file_name = STRBUF_INIT;
+ struct strbuf tab_file_name = STRBUF_INIT;
+ struct strbuf next_name = STRBUF_INIT;
+ struct reftable_writer *wr = NULL;
+ int err = 0;
+ int tab_fd = 0;
+
+ strbuf_reset(&next_name);
+ format_name(&next_name, add->next_update_index, add->next_update_index);
+
+ strbuf_addstr(&temp_tab_file_name, add->stack->reftable_dir);
+ strbuf_addstr(&temp_tab_file_name, "/");
+ strbuf_addbuf(&temp_tab_file_name, &next_name);
+ strbuf_addstr(&temp_tab_file_name, ".temp.XXXXXX");
+
+ tab_fd = mkstemp(temp_tab_file_name.buf);
+ if (tab_fd < 0) {
+ err = REFTABLE_IO_ERROR;
+ goto done;
+ }
+
+ wr = reftable_new_writer(reftable_fd_write, &tab_fd,
+ &add->stack->config);
+ err = write_table(wr, arg);
+ if (err < 0)
+ goto done;
+
+ err = reftable_writer_close(wr);
+ if (err == REFTABLE_EMPTY_TABLE_ERROR) {
+ err = 0;
+ goto done;
+ }
+ if (err < 0)
+ goto done;
+
+ err = close(tab_fd);
+ tab_fd = 0;
+ if (err < 0) {
+ err = REFTABLE_IO_ERROR;
+ goto done;
+ }
+
+ err = stack_check_addition(add->stack, temp_tab_file_name.buf);
+ if (err < 0)
+ goto done;
+
+ if (wr->min_update_index < add->next_update_index) {
+ err = REFTABLE_API_ERROR;
+ goto done;
+ }
+
+ format_name(&next_name, wr->min_update_index, wr->max_update_index);
+ strbuf_addstr(&next_name, ".ref");
+
+ strbuf_addstr(&tab_file_name, add->stack->reftable_dir);
+ strbuf_addstr(&tab_file_name, "/");
+ strbuf_addbuf(&tab_file_name, &next_name);
+
+ /* TODO: should check destination out of paranoia */
+ err = rename(temp_tab_file_name.buf, tab_file_name.buf);
+ if (err < 0) {
+ err = REFTABLE_IO_ERROR;
+ goto done;
+ }
+
+ add->new_tables = reftable_realloc(add->new_tables,
+ sizeof(*add->new_tables) *
+ (add->new_tables_len + 1));
+ add->new_tables[add->new_tables_len] = strbuf_detach(&next_name, NULL);
+ add->new_tables_len++;
+done:
+ if (tab_fd > 0) {
+ close(tab_fd);
+ tab_fd = 0;
+ }
+ if (temp_tab_file_name.len > 0) {
+ unlink(temp_tab_file_name.buf);
+ }
+
+ strbuf_release(&temp_tab_file_name);
+ strbuf_release(&tab_file_name);
+ strbuf_release(&next_name);
+ reftable_writer_free(wr);
+ return err;
+}
+
+uint64_t reftable_stack_next_update_index(struct reftable_stack *st)
+{
+ int sz = st->merged->stack_len;
+ if (sz > 0)
+ return reftable_reader_max_update_index(st->readers[sz - 1]) +
+ 1;
+ return 1;
+}
+
+static int stack_compact_locked(struct reftable_stack *st, int first, int last,
+ struct strbuf *temp_tab,
+ struct reftable_log_expiry_config *config)
+{
+ struct strbuf next_name = STRBUF_INIT;
+ int tab_fd = -1;
+ struct reftable_writer *wr = NULL;
+ int err = 0;
+
+ format_name(&next_name,
+ reftable_reader_min_update_index(st->readers[first]),
+ reftable_reader_max_update_index(st->readers[first]));
+
+ strbuf_reset(temp_tab);
+ strbuf_addstr(temp_tab, st->reftable_dir);
+ strbuf_addstr(temp_tab, "/");
+ strbuf_addbuf(temp_tab, &next_name);
+ strbuf_addstr(temp_tab, ".temp.XXXXXX");
+
+ tab_fd = mkstemp(temp_tab->buf);
+ wr = reftable_new_writer(reftable_fd_write, &tab_fd, &st->config);
+
+ err = stack_write_compact(st, wr, first, last, config);
+ if (err < 0)
+ goto done;
+ err = reftable_writer_close(wr);
+ if (err < 0)
+ goto done;
+
+ err = close(tab_fd);
+ tab_fd = 0;
+
+done:
+ reftable_writer_free(wr);
+ if (tab_fd > 0) {
+ close(tab_fd);
+ tab_fd = 0;
+ }
+ if (err != 0 && temp_tab->len > 0) {
+ unlink(temp_tab->buf);
+ strbuf_release(temp_tab);
+ }
+ strbuf_release(&next_name);
+ return err;
+}
+
+static int stack_write_compact(struct reftable_stack *st,
+ struct reftable_writer *wr, int first, int last,
+ struct reftable_log_expiry_config *config)
+{
+ int subtabs_len = last - first + 1;
+ struct reftable_table *subtabs = reftable_calloc(
+ sizeof(struct reftable_table) * (last - first + 1));
+ struct reftable_merged_table *mt = NULL;
+ int err = 0;
+ struct reftable_iterator it = { NULL };
+ struct reftable_ref_record ref = { NULL };
+ struct reftable_log_record log = { NULL };
+
+ uint64_t entries = 0;
+
+ int i = 0, j = 0;
+ for (i = first, j = 0; i <= last; i++) {
+ struct reftable_reader *t = st->readers[i];
+ reftable_table_from_reader(&subtabs[j++], t);
+ st->stats.bytes += t->size;
+ }
+ reftable_writer_set_limits(wr, st->readers[first]->min_update_index,
+ st->readers[last]->max_update_index);
+
+ err = reftable_new_merged_table(&mt, subtabs, subtabs_len,
+ st->config.hash_id);
+ if (err < 0) {
+ reftable_free(subtabs);
+ goto done;
+ }
+
+ err = reftable_merged_table_seek_ref(mt, &it, "");
+ if (err < 0)
+ goto done;
+
+ while (1) {
+ err = reftable_iterator_next_ref(&it, &ref);
+ if (err > 0) {
+ err = 0;
+ break;
+ }
+ if (err < 0) {
+ break;
+ }
+ if (first == 0 && reftable_ref_record_is_deletion(&ref)) {
+ continue;
+ }
+
+ err = reftable_writer_add_ref(wr, &ref);
+ if (err < 0) {
+ break;
+ }
+ entries++;
+ }
+ reftable_iterator_destroy(&it);
+
+ err = reftable_merged_table_seek_log(mt, &it, "");
+ if (err < 0)
+ goto done;
+
+ while (1) {
+ err = reftable_iterator_next_log(&it, &log);
+ if (err > 0) {
+ err = 0;
+ break;
+ }
+ if (err < 0) {
+ break;
+ }
+ if (first == 0 && reftable_log_record_is_deletion(&log)) {
+ continue;
+ }
+
+ if (config != NULL && config->time > 0 &&
+ log.time < config->time) {
+ continue;
+ }
+
+ if (config != NULL && config->min_update_index > 0 &&
+ log.update_index < config->min_update_index) {
+ continue;
+ }
+
+ err = reftable_writer_add_log(wr, &log);
+ if (err < 0) {
+ break;
+ }
+ entries++;
+ }
+
+done:
+ reftable_iterator_destroy(&it);
+ if (mt != NULL) {
+ merged_table_release(mt);
+ reftable_merged_table_free(mt);
+ }
+ reftable_ref_record_release(&ref);
+ reftable_log_record_release(&log);
+ st->stats.entries_written += entries;
+ return err;
+}
+
+/* < 0: error. 0 == OK, > 0 attempt failed; could retry. */
+static int stack_compact_range(struct reftable_stack *st, int first, int last,
+ struct reftable_log_expiry_config *expiry)
+{
+ struct strbuf temp_tab_file_name = STRBUF_INIT;
+ struct strbuf new_table_name = STRBUF_INIT;
+ struct strbuf lock_file_name = STRBUF_INIT;
+ struct strbuf ref_list_contents = STRBUF_INIT;
+ struct strbuf new_table_path = STRBUF_INIT;
+ int err = 0;
+ int have_lock = 0;
+ int lock_file_fd = 0;
+ int compact_count = last - first + 1;
+ char **listp = NULL;
+ char **delete_on_success =
+ reftable_calloc(sizeof(char *) * (compact_count + 1));
+ char **subtable_locks =
+ reftable_calloc(sizeof(char *) * (compact_count + 1));
+ int i = 0;
+ int j = 0;
+ int is_empty_table = 0;
+
+ if (first > last || (expiry == NULL && first == last)) {
+ err = 0;
+ goto done;
+ }
+
+ st->stats.attempts++;
+
+ strbuf_reset(&lock_file_name);
+ strbuf_addstr(&lock_file_name, st->list_file);
+ strbuf_addstr(&lock_file_name, ".lock");
+
+ lock_file_fd =
+ open(lock_file_name.buf, O_EXCL | O_CREAT | O_WRONLY, 0644);
+ if (lock_file_fd < 0) {
+ if (errno == EEXIST) {
+ err = 1;
+ } else {
+ err = REFTABLE_IO_ERROR;
+ }
+ goto done;
+ }
+ /* Don't want to write to the lock for now. */
+ close(lock_file_fd);
+ lock_file_fd = 0;
+
+ have_lock = 1;
+ err = stack_uptodate(st);
+ if (err != 0)
+ goto done;
+
+ for (i = first, j = 0; i <= last; i++) {
+ struct strbuf subtab_file_name = STRBUF_INIT;
+ struct strbuf subtab_lock = STRBUF_INIT;
+ int sublock_file_fd = -1;
+
+ strbuf_addstr(&subtab_file_name, st->reftable_dir);
+ strbuf_addstr(&subtab_file_name, "/");
+ strbuf_addstr(&subtab_file_name, reader_name(st->readers[i]));
+
+ strbuf_reset(&subtab_lock);
+ strbuf_addbuf(&subtab_lock, &subtab_file_name);
+ strbuf_addstr(&subtab_lock, ".lock");
+
+ sublock_file_fd = open(subtab_lock.buf,
+ O_EXCL | O_CREAT | O_WRONLY, 0644);
+ if (sublock_file_fd > 0) {
+ close(sublock_file_fd);
+ } else if (sublock_file_fd < 0) {
+ if (errno == EEXIST) {
+ err = 1;
+ } else {
+ err = REFTABLE_IO_ERROR;
+ }
+ }
+
+ subtable_locks[j] = subtab_lock.buf;
+ delete_on_success[j] = subtab_file_name.buf;
+ j++;
+
+ if (err != 0)
+ goto done;
+ }
+
+ err = unlink(lock_file_name.buf);
+ if (err < 0)
+ goto done;
+ have_lock = 0;
+
+ err = stack_compact_locked(st, first, last, &temp_tab_file_name,
+ expiry);
+ /* Compaction + tombstones can create an empty table out of non-empty
+ * tables. */
+ is_empty_table = (err == REFTABLE_EMPTY_TABLE_ERROR);
+ if (is_empty_table) {
+ err = 0;
+ }
+ if (err < 0)
+ goto done;
+
+ lock_file_fd =
+ open(lock_file_name.buf, O_EXCL | O_CREAT | O_WRONLY, 0644);
+ if (lock_file_fd < 0) {
+ if (errno == EEXIST) {
+ err = 1;
+ } else {
+ err = REFTABLE_IO_ERROR;
+ }
+ goto done;
+ }
+ have_lock = 1;
+
+ format_name(&new_table_name, st->readers[first]->min_update_index,
+ st->readers[last]->max_update_index);
+ strbuf_addstr(&new_table_name, ".ref");
+
+ strbuf_reset(&new_table_path);
+ strbuf_addstr(&new_table_path, st->reftable_dir);
+ strbuf_addstr(&new_table_path, "/");
+ strbuf_addbuf(&new_table_path, &new_table_name);
+
+ if (!is_empty_table) {
+ err = rename(temp_tab_file_name.buf, new_table_path.buf);
+ if (err < 0) {
+ err = REFTABLE_IO_ERROR;
+ goto done;
+ }
+ }
+
+ for (i = 0; i < first; i++) {
+ strbuf_addstr(&ref_list_contents, st->readers[i]->name);
+ strbuf_addstr(&ref_list_contents, "\n");
+ }
+ if (!is_empty_table) {
+ strbuf_addbuf(&ref_list_contents, &new_table_name);
+ strbuf_addstr(&ref_list_contents, "\n");
+ }
+ for (i = last + 1; i < st->merged->stack_len; i++) {
+ strbuf_addstr(&ref_list_contents, st->readers[i]->name);
+ strbuf_addstr(&ref_list_contents, "\n");
+ }
+
+ err = write(lock_file_fd, ref_list_contents.buf, ref_list_contents.len);
+ if (err < 0) {
+ err = REFTABLE_IO_ERROR;
+ unlink(new_table_path.buf);
+ goto done;
+ }
+ err = close(lock_file_fd);
+ lock_file_fd = 0;
+ if (err < 0) {
+ err = REFTABLE_IO_ERROR;
+ unlink(new_table_path.buf);
+ goto done;
+ }
+
+ err = rename(lock_file_name.buf, st->list_file);
+ if (err < 0) {
+ err = REFTABLE_IO_ERROR;
+ unlink(new_table_path.buf);
+ goto done;
+ }
+ have_lock = 0;
+
+ /* Reload the stack before deleting. On windows, we can only delete the
+ files after we closed them.
+ */
+ err = reftable_stack_reload_maybe_reuse(st, first < last);
+
+ listp = delete_on_success;
+ while (*listp) {
+ if (strcmp(*listp, new_table_path.buf)) {
+ unlink(*listp);
+ }
+ listp++;
+ }
+
+done:
+ free_names(delete_on_success);
+
+ listp = subtable_locks;
+ while (*listp) {
+ unlink(*listp);
+ listp++;
+ }
+ free_names(subtable_locks);
+ if (lock_file_fd > 0) {
+ close(lock_file_fd);
+ lock_file_fd = 0;
+ }
+ if (have_lock) {
+ unlink(lock_file_name.buf);
+ }
+ strbuf_release(&new_table_name);
+ strbuf_release(&new_table_path);
+ strbuf_release(&ref_list_contents);
+ strbuf_release(&temp_tab_file_name);
+ strbuf_release(&lock_file_name);
+ return err;
+}
+
+int reftable_stack_compact_all(struct reftable_stack *st,
+ struct reftable_log_expiry_config *config)
+{
+ return stack_compact_range(st, 0, st->merged->stack_len - 1, config);
+}
+
+static int stack_compact_range_stats(struct reftable_stack *st, int first,
+ int last,
+ struct reftable_log_expiry_config *config)
+{
+ int err = stack_compact_range(st, first, last, config);
+ if (err > 0) {
+ st->stats.failures++;
+ }
+ return err;
+}
+
+static int segment_size(struct segment *s)
+{
+ return s->end - s->start;
+}
+
+int fastlog2(uint64_t sz)
+{
+ int l = 0;
+ if (sz == 0)
+ return 0;
+ for (; sz; sz /= 2) {
+ l++;
+ }
+ return l - 1;
+}
+
+struct segment *sizes_to_segments(int *seglen, uint64_t *sizes, int n)
+{
+ struct segment *segs = reftable_calloc(sizeof(struct segment) * n);
+ int next = 0;
+ struct segment cur = { 0 };
+ int i = 0;
+
+ if (n == 0) {
+ *seglen = 0;
+ return segs;
+ }
+ for (i = 0; i < n; i++) {
+ int log = fastlog2(sizes[i]);
+ if (cur.log != log && cur.bytes > 0) {
+ struct segment fresh = {
+ .start = i,
+ };
+
+ segs[next++] = cur;
+ cur = fresh;
+ }
+
+ cur.log = log;
+ cur.end = i + 1;
+ cur.bytes += sizes[i];
+ }
+ segs[next++] = cur;
+ *seglen = next;
+ return segs;
+}
+
+struct segment suggest_compaction_segment(uint64_t *sizes, int n)
+{
+ int seglen = 0;
+ struct segment *segs = sizes_to_segments(&seglen, sizes, n);
+ struct segment min_seg = {
+ .log = 64,
+ };
+ int i = 0;
+ for (i = 0; i < seglen; i++) {
+ if (segment_size(&segs[i]) == 1) {
+ continue;
+ }
+
+ if (segs[i].log < min_seg.log) {
+ min_seg = segs[i];
+ }
+ }
+
+ while (min_seg.start > 0) {
+ int prev = min_seg.start - 1;
+ if (fastlog2(min_seg.bytes) < fastlog2(sizes[prev])) {
+ break;
+ }
+
+ min_seg.start = prev;
+ min_seg.bytes += sizes[prev];
+ }
+
+ reftable_free(segs);
+ return min_seg;
+}
+
+static uint64_t *stack_table_sizes_for_compaction(struct reftable_stack *st)
+{
+ uint64_t *sizes =
+ reftable_calloc(sizeof(uint64_t) * st->merged->stack_len);
+ int version = (st->config.hash_id == SHA1_ID) ? 1 : 2;
+ int overhead = header_size(version) - 1;
+ int i = 0;
+ for (i = 0; i < st->merged->stack_len; i++) {
+ sizes[i] = st->readers[i]->size - overhead;
+ }
+ return sizes;
+}
+
+int reftable_stack_auto_compact(struct reftable_stack *st)
+{
+ uint64_t *sizes = stack_table_sizes_for_compaction(st);
+ struct segment seg =
+ suggest_compaction_segment(sizes, st->merged->stack_len);
+ reftable_free(sizes);
+ if (segment_size(&seg) > 0)
+ return stack_compact_range_stats(st, seg.start, seg.end - 1,
+ NULL);
+
+ return 0;
+}
+
+struct reftable_compaction_stats *
+reftable_stack_compaction_stats(struct reftable_stack *st)
+{
+ return &st->stats;
+}
+
+int reftable_stack_read_ref(struct reftable_stack *st, const char *refname,
+ struct reftable_ref_record *ref)
+{
+ struct reftable_table tab = { NULL };
+ reftable_table_from_merged_table(&tab, reftable_stack_merged_table(st));
+ return reftable_table_read_ref(&tab, refname, ref);
+}
+
+int reftable_stack_read_log(struct reftable_stack *st, const char *refname,
+ struct reftable_log_record *log)
+{
+ struct reftable_iterator it = { NULL };
+ struct reftable_merged_table *mt = reftable_stack_merged_table(st);
+ int err = reftable_merged_table_seek_log(mt, &it, refname);
+ if (err)
+ goto done;
+
+ err = reftable_iterator_next_log(&it, log);
+ if (err)
+ goto done;
+
+ if (strcmp(log->refname, refname) ||
+ reftable_log_record_is_deletion(log)) {
+ err = 1;
+ goto done;
+ }
+
+done:
+ if (err) {
+ reftable_log_record_release(log);
+ }
+ reftable_iterator_destroy(&it);
+ return err;
+}
+
+static int stack_check_addition(struct reftable_stack *st,
+ const char *new_tab_name)
+{
+ int err = 0;
+ struct reftable_block_source src = { NULL };
+ struct reftable_reader *rd = NULL;
+ struct reftable_table tab = { NULL };
+ struct reftable_ref_record *refs = NULL;
+ struct reftable_iterator it = { NULL };
+ int cap = 0;
+ int len = 0;
+ int i = 0;
+
+ if (st->config.skip_name_check)
+ return 0;
+
+ err = reftable_block_source_from_file(&src, new_tab_name);
+ if (err < 0)
+ goto done;
+
+ err = reftable_new_reader(&rd, &src, new_tab_name);
+ if (err < 0)
+ goto done;
+
+ err = reftable_reader_seek_ref(rd, &it, "");
+ if (err > 0) {
+ err = 0;
+ goto done;
+ }
+ if (err < 0)
+ goto done;
+
+ while (1) {
+ struct reftable_ref_record ref = { NULL };
+ err = reftable_iterator_next_ref(&it, &ref);
+ if (err > 0) {
+ break;
+ }
+ if (err < 0)
+ goto done;
+
+ if (len >= cap) {
+ cap = 2 * cap + 1;
+ refs = reftable_realloc(refs, cap * sizeof(refs[0]));
+ }
+
+ refs[len++] = ref;
+ }
+
+ reftable_table_from_merged_table(&tab, reftable_stack_merged_table(st));
+
+ err = validate_ref_record_addition(tab, refs, len);
+
+done:
+ for (i = 0; i < len; i++) {
+ reftable_ref_record_release(&refs[i]);
+ }
+
+ free(refs);
+ reftable_iterator_destroy(&it);
+ reftable_reader_free(rd);
+ return err;
+}
diff --git a/reftable/stack.h b/reftable/stack.h
new file mode 100644
index 0000000000..f57005846e
--- /dev/null
+++ b/reftable/stack.h
@@ -0,0 +1,41 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef STACK_H
+#define STACK_H
+
+#include "system.h"
+#include "reftable-writer.h"
+#include "reftable-stack.h"
+
+struct reftable_stack {
+ char *list_file;
+ char *reftable_dir;
+ int disable_auto_compact;
+
+ struct reftable_write_options config;
+
+ struct reftable_reader **readers;
+ size_t readers_len;
+ struct reftable_merged_table *merged;
+ struct reftable_compaction_stats stats;
+};
+
+int read_lines(const char *filename, char ***lines);
+
+struct segment {
+ int start, end;
+ int log;
+ uint64_t bytes;
+};
+
+int fastlog2(uint64_t sz);
+struct segment *sizes_to_segments(int *seglen, uint64_t *sizes, int n);
+struct segment suggest_compaction_segment(uint64_t *sizes, int n);
+
+#endif
diff --git a/reftable/stack_test.c b/reftable/stack_test.c
new file mode 100644
index 0000000000..11d3d30799
--- /dev/null
+++ b/reftable/stack_test.c
@@ -0,0 +1,781 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "stack.h"
+
+#include "system.h"
+
+#include "merged.h"
+#include "basics.h"
+#include "constants.h"
+#include "record.h"
+#include "test_framework.h"
+#include "reftable-tests.h"
+
+#include <sys/types.h>
+#include <dirent.h>
+
+static void clear_dir(const char *dirname)
+{
+ struct strbuf path = STRBUF_INIT;
+ strbuf_addstr(&path, dirname);
+ remove_dir_recursively(&path, 0);
+ strbuf_release(&path);
+}
+
+static void test_read_file(void)
+{
+ char fn[256] = "/tmp/stack.test_read_file.XXXXXX";
+ int fd = mkstemp(fn);
+ char out[1024] = "line1\n\nline2\nline3";
+ int n, err;
+ char **names = NULL;
+ char *want[] = { "line1", "line2", "line3" };
+ int i = 0;
+
+ EXPECT(fd > 0);
+ n = write(fd, out, strlen(out));
+ EXPECT(n == strlen(out));
+ err = close(fd);
+ EXPECT(err >= 0);
+
+ err = read_lines(fn, &names);
+ EXPECT_ERR(err);
+
+ for (i = 0; names[i] != NULL; i++) {
+ EXPECT(0 == strcmp(want[i], names[i]));
+ }
+ free_names(names);
+ remove(fn);
+}
+
+static void test_parse_names(void)
+{
+ char buf[] = "line\n";
+ char **names = NULL;
+ parse_names(buf, strlen(buf), &names);
+
+ EXPECT(NULL != names[0]);
+ EXPECT(0 == strcmp(names[0], "line"));
+ EXPECT(NULL == names[1]);
+ free_names(names);
+}
+
+static void test_names_equal(void)
+{
+ char *a[] = { "a", "b", "c", NULL };
+ char *b[] = { "a", "b", "d", NULL };
+ char *c[] = { "a", "b", NULL };
+
+ EXPECT(names_equal(a, a));
+ EXPECT(!names_equal(a, b));
+ EXPECT(!names_equal(a, c));
+}
+
+static int write_test_ref(struct reftable_writer *wr, void *arg)
+{
+ struct reftable_ref_record *ref = arg;
+ reftable_writer_set_limits(wr, ref->update_index, ref->update_index);
+ return reftable_writer_add_ref(wr, ref);
+}
+
+struct write_log_arg {
+ struct reftable_log_record *log;
+ uint64_t update_index;
+};
+
+static int write_test_log(struct reftable_writer *wr, void *arg)
+{
+ struct write_log_arg *wla = arg;
+
+ reftable_writer_set_limits(wr, wla->update_index, wla->update_index);
+ return reftable_writer_add_log(wr, wla->log);
+}
+
+static void test_reftable_stack_add_one(void)
+{
+ char dir[256] = "/tmp/stack_test.XXXXXX";
+ struct reftable_write_options cfg = { 0 };
+ struct reftable_stack *st = NULL;
+ int err;
+ struct reftable_ref_record ref = {
+ .refname = "HEAD",
+ .update_index = 1,
+ .target = "master",
+ };
+ struct reftable_ref_record dest = { NULL };
+
+ EXPECT(mkdtemp(dir));
+
+ err = reftable_new_stack(&st, dir, cfg);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_add(st, &write_test_ref, &ref);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_read_ref(st, ref.refname, &dest);
+ EXPECT_ERR(err);
+ EXPECT(0 == strcmp("master", dest.target));
+
+ reftable_ref_record_release(&dest);
+ reftable_stack_destroy(st);
+ clear_dir(dir);
+}
+
+static void test_reftable_stack_uptodate(void)
+{
+ struct reftable_write_options cfg = { 0 };
+ struct reftable_stack *st1 = NULL;
+ struct reftable_stack *st2 = NULL;
+ char dir[256] = "/tmp/stack_test.XXXXXX";
+ int err;
+ struct reftable_ref_record ref1 = {
+ .refname = "HEAD",
+ .update_index = 1,
+ .target = "master",
+ };
+ struct reftable_ref_record ref2 = {
+ .refname = "branch2",
+ .update_index = 2,
+ .target = "master",
+ };
+
+ EXPECT(mkdtemp(dir));
+
+ err = reftable_new_stack(&st1, dir, cfg);
+ EXPECT_ERR(err);
+
+ err = reftable_new_stack(&st2, dir, cfg);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_add(st1, &write_test_ref, &ref1);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_add(st2, &write_test_ref, &ref2);
+ EXPECT(err == REFTABLE_LOCK_ERROR);
+
+ err = reftable_stack_reload(st2);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_add(st2, &write_test_ref, &ref2);
+ EXPECT_ERR(err);
+ reftable_stack_destroy(st1);
+ reftable_stack_destroy(st2);
+ clear_dir(dir);
+}
+
+static void test_reftable_stack_transaction_api(void)
+{
+ char dir[256] = "/tmp/stack_test.XXXXXX";
+ struct reftable_write_options cfg = { 0 };
+ struct reftable_stack *st = NULL;
+ int err;
+ struct reftable_addition *add = NULL;
+
+ struct reftable_ref_record ref = {
+ .refname = "HEAD",
+ .update_index = 1,
+ .target = "master",
+ };
+ struct reftable_ref_record dest = { NULL };
+
+ EXPECT(mkdtemp(dir));
+
+ err = reftable_new_stack(&st, dir, cfg);
+ EXPECT_ERR(err);
+
+ reftable_addition_destroy(add);
+
+ err = reftable_stack_new_addition(&add, st);
+ EXPECT_ERR(err);
+
+ err = reftable_addition_add(add, &write_test_ref, &ref);
+ EXPECT_ERR(err);
+
+ err = reftable_addition_commit(add);
+ EXPECT_ERR(err);
+
+ reftable_addition_destroy(add);
+
+ err = reftable_stack_read_ref(st, ref.refname, &dest);
+ EXPECT_ERR(err);
+ EXPECT(0 == strcmp("master", dest.target));
+
+ reftable_ref_record_release(&dest);
+ reftable_stack_destroy(st);
+ clear_dir(dir);
+}
+
+static void test_reftable_stack_validate_refname(void)
+{
+ struct reftable_write_options cfg = { 0 };
+ struct reftable_stack *st = NULL;
+ int err;
+ char dir[256] = "/tmp/stack_test.XXXXXX";
+ int i;
+ struct reftable_ref_record ref = {
+ .refname = "a/b",
+ .update_index = 1,
+ .target = "master",
+ };
+ char *additions[] = { "a", "a/b/c" };
+
+ EXPECT(mkdtemp(dir));
+ err = reftable_new_stack(&st, dir, cfg);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_add(st, &write_test_ref, &ref);
+ EXPECT_ERR(err);
+
+ for (i = 0; i < ARRAY_SIZE(additions); i++) {
+ struct reftable_ref_record ref = {
+ .refname = additions[i],
+ .update_index = 1,
+ .target = "master",
+ };
+
+ err = reftable_stack_add(st, &write_test_ref, &ref);
+ EXPECT(err == REFTABLE_NAME_CONFLICT);
+ }
+
+ reftable_stack_destroy(st);
+ clear_dir(dir);
+}
+
+static int write_error(struct reftable_writer *wr, void *arg)
+{
+ return *((int *)arg);
+}
+
+static void test_reftable_stack_update_index_check(void)
+{
+ char dir[256] = "/tmp/stack_test.XXXXXX";
+ struct reftable_write_options cfg = { 0 };
+ struct reftable_stack *st = NULL;
+ int err;
+ struct reftable_ref_record ref1 = {
+ .refname = "name1",
+ .update_index = 1,
+ .target = "master",
+ };
+ struct reftable_ref_record ref2 = {
+ .refname = "name2",
+ .update_index = 1,
+ .target = "master",
+ };
+ EXPECT(mkdtemp(dir));
+
+ err = reftable_new_stack(&st, dir, cfg);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_add(st, &write_test_ref, &ref1);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_add(st, &write_test_ref, &ref2);
+ EXPECT(err == REFTABLE_API_ERROR);
+ reftable_stack_destroy(st);
+ clear_dir(dir);
+}
+
+static void test_reftable_stack_lock_failure(void)
+{
+ char dir[256] = "/tmp/stack_test.XXXXXX";
+ struct reftable_write_options cfg = { 0 };
+ struct reftable_stack *st = NULL;
+ int err, i;
+ EXPECT(mkdtemp(dir));
+
+ err = reftable_new_stack(&st, dir, cfg);
+ EXPECT_ERR(err);
+ for (i = -1; i != REFTABLE_EMPTY_TABLE_ERROR; i--) {
+ err = reftable_stack_add(st, &write_error, &i);
+ EXPECT(err == i);
+ }
+
+ reftable_stack_destroy(st);
+ clear_dir(dir);
+}
+
+static void test_reftable_stack_add(void)
+{
+ int i = 0;
+ int err = 0;
+ struct reftable_write_options cfg = {
+ .exact_log_message = 1,
+ };
+ struct reftable_stack *st = NULL;
+ char dir[256] = "/tmp/stack_test.XXXXXX";
+ struct reftable_ref_record refs[2] = { { NULL } };
+ struct reftable_log_record logs[2] = { { NULL } };
+ int N = ARRAY_SIZE(refs);
+
+ EXPECT(mkdtemp(dir));
+
+ err = reftable_new_stack(&st, dir, cfg);
+ EXPECT_ERR(err);
+ st->disable_auto_compact = 1;
+
+ for (i = 0; i < N; i++) {
+ char buf[256];
+ snprintf(buf, sizeof(buf), "branch%02d", i);
+ refs[i].refname = xstrdup(buf);
+ refs[i].value = reftable_malloc(SHA1_SIZE);
+ refs[i].update_index = i + 1;
+ set_test_hash(refs[i].value, i);
+
+ logs[i].refname = xstrdup(buf);
+ logs[i].update_index = N + i + 1;
+ logs[i].new_hash = reftable_malloc(SHA1_SIZE);
+ logs[i].email = xstrdup("identity@invalid");
+ set_test_hash(logs[i].new_hash, i);
+ }
+
+ for (i = 0; i < N; i++) {
+ int err = reftable_stack_add(st, &write_test_ref, &refs[i]);
+ EXPECT_ERR(err);
+ }
+
+ for (i = 0; i < N; i++) {
+ struct write_log_arg arg = {
+ .log = &logs[i],
+ .update_index = reftable_stack_next_update_index(st),
+ };
+ int err = reftable_stack_add(st, &write_test_log, &arg);
+ EXPECT_ERR(err);
+ }
+
+ err = reftable_stack_compact_all(st, NULL);
+ EXPECT_ERR(err);
+
+ for (i = 0; i < N; i++) {
+ struct reftable_ref_record dest = { NULL };
+
+ int err = reftable_stack_read_ref(st, refs[i].refname, &dest);
+ EXPECT_ERR(err);
+ EXPECT(reftable_ref_record_equal(&dest, refs + i, SHA1_SIZE));
+ reftable_ref_record_release(&dest);
+ }
+
+ for (i = 0; i < N; i++) {
+ struct reftable_log_record dest = { NULL };
+ int err = reftable_stack_read_log(st, refs[i].refname, &dest);
+ EXPECT_ERR(err);
+ EXPECT(reftable_log_record_equal(&dest, logs + i, SHA1_SIZE));
+ reftable_log_record_release(&dest);
+ }
+
+ /* cleanup */
+ reftable_stack_destroy(st);
+ for (i = 0; i < N; i++) {
+ reftable_ref_record_release(&refs[i]);
+ reftable_log_record_release(&logs[i]);
+ }
+ clear_dir(dir);
+}
+
+static void test_reftable_stack_log_normalize(void)
+{
+ int err = 0;
+ struct reftable_write_options cfg = {
+ 0,
+ };
+ struct reftable_stack *st = NULL;
+ char dir[256] = "/tmp/stack_test.XXXXXX";
+
+ uint8_t h1[SHA1_SIZE] = { 0x01 }, h2[SHA1_SIZE] = { 0x02 };
+
+ struct reftable_log_record input = {
+ .refname = "branch",
+ .update_index = 1,
+ .new_hash = h1,
+ .old_hash = h2,
+ };
+ struct reftable_log_record dest = {
+ .update_index = 0,
+ };
+ struct write_log_arg arg = {
+ .log = &input,
+ .update_index = 1,
+ };
+
+ EXPECT(mkdtemp(dir));
+ err = reftable_new_stack(&st, dir, cfg);
+ EXPECT_ERR(err);
+
+ input.message = "one\ntwo";
+ err = reftable_stack_add(st, &write_test_log, &arg);
+ EXPECT(err == REFTABLE_API_ERROR);
+
+ input.message = "one";
+ err = reftable_stack_add(st, &write_test_log, &arg);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_read_log(st, input.refname, &dest);
+ EXPECT_ERR(err);
+ EXPECT(0 == strcmp(dest.message, "one\n"));
+
+ input.message = "two\n";
+ arg.update_index = 2;
+ err = reftable_stack_add(st, &write_test_log, &arg);
+ EXPECT_ERR(err);
+ err = reftable_stack_read_log(st, input.refname, &dest);
+ EXPECT_ERR(err);
+ EXPECT(0 == strcmp(dest.message, "two\n"));
+
+ /* cleanup */
+ reftable_stack_destroy(st);
+ reftable_log_record_release(&dest);
+ clear_dir(dir);
+}
+
+static void test_reftable_stack_tombstone(void)
+{
+ int i = 0;
+ char dir[256] = "/tmp/stack_test.XXXXXX";
+ struct reftable_write_options cfg = { 0 };
+ struct reftable_stack *st = NULL;
+ int err;
+ struct reftable_ref_record refs[2] = { { NULL } };
+ struct reftable_log_record logs[2] = { { NULL } };
+ int N = ARRAY_SIZE(refs);
+ struct reftable_ref_record dest = { NULL };
+ struct reftable_log_record log_dest = { NULL };
+
+ EXPECT(mkdtemp(dir));
+
+ err = reftable_new_stack(&st, dir, cfg);
+ EXPECT_ERR(err);
+
+ for (i = 0; i < N; i++) {
+ const char *buf = "branch";
+ refs[i].refname = xstrdup(buf);
+ refs[i].update_index = i + 1;
+ if (i % 2 == 0) {
+ refs[i].value = reftable_malloc(SHA1_SIZE);
+ set_test_hash(refs[i].value, i);
+ }
+ logs[i].refname = xstrdup(buf);
+ /* update_index is part of the key. */
+ logs[i].update_index = 42;
+ if (i % 2 == 0) {
+ logs[i].new_hash = reftable_malloc(SHA1_SIZE);
+ set_test_hash(logs[i].new_hash, i);
+ logs[i].email = xstrdup("identity@invalid");
+ }
+ }
+ for (i = 0; i < N; i++) {
+ int err = reftable_stack_add(st, &write_test_ref, &refs[i]);
+ EXPECT_ERR(err);
+ }
+ for (i = 0; i < N; i++) {
+ struct write_log_arg arg = {
+ .log = &logs[i],
+ .update_index = reftable_stack_next_update_index(st),
+ };
+ int err = reftable_stack_add(st, &write_test_log, &arg);
+ EXPECT_ERR(err);
+ }
+
+ err = reftable_stack_read_ref(st, "branch", &dest);
+ EXPECT(err == 1);
+ reftable_ref_record_release(&dest);
+
+ err = reftable_stack_read_log(st, "branch", &log_dest);
+ EXPECT(err == 1);
+ reftable_log_record_release(&log_dest);
+
+ err = reftable_stack_compact_all(st, NULL);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_read_ref(st, "branch", &dest);
+ EXPECT(err == 1);
+
+ err = reftable_stack_read_log(st, "branch", &log_dest);
+ EXPECT(err == 1);
+ reftable_ref_record_release(&dest);
+ reftable_log_record_release(&log_dest);
+
+ /* cleanup */
+ reftable_stack_destroy(st);
+ for (i = 0; i < N; i++) {
+ reftable_ref_record_release(&refs[i]);
+ reftable_log_record_release(&logs[i]);
+ }
+ clear_dir(dir);
+}
+
+static void test_reftable_stack_hash_id(void)
+{
+ char dir[256] = "/tmp/stack_test.XXXXXX";
+ struct reftable_write_options cfg = { 0 };
+ struct reftable_stack *st = NULL;
+ int err;
+
+ struct reftable_ref_record ref = {
+ .refname = "master",
+ .target = "target",
+ .update_index = 1,
+ };
+ struct reftable_write_options cfg32 = { .hash_id = SHA256_ID };
+ struct reftable_stack *st32 = NULL;
+ struct reftable_write_options cfg_default = { 0 };
+ struct reftable_stack *st_default = NULL;
+ struct reftable_ref_record dest = { NULL };
+
+ EXPECT(mkdtemp(dir));
+ err = reftable_new_stack(&st, dir, cfg);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_add(st, &write_test_ref, &ref);
+ EXPECT_ERR(err);
+
+ /* can't read it with the wrong hash ID. */
+ err = reftable_new_stack(&st32, dir, cfg32);
+ EXPECT(err == REFTABLE_FORMAT_ERROR);
+
+ /* check that we can read it back with default config too. */
+ err = reftable_new_stack(&st_default, dir, cfg_default);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_read_ref(st_default, "master", &dest);
+ EXPECT_ERR(err);
+
+ EXPECT(!strcmp(dest.target, ref.target));
+ reftable_ref_record_release(&dest);
+ reftable_stack_destroy(st);
+ reftable_stack_destroy(st_default);
+ clear_dir(dir);
+}
+
+static void test_log2(void)
+{
+ EXPECT(1 == fastlog2(3));
+ EXPECT(2 == fastlog2(4));
+ EXPECT(2 == fastlog2(5));
+}
+
+static void test_sizes_to_segments(void)
+{
+ uint64_t sizes[] = { 2, 3, 4, 5, 7, 9 };
+ /* .................0 1 2 3 4 5 */
+
+ int seglen = 0;
+ struct segment *segs =
+ sizes_to_segments(&seglen, sizes, ARRAY_SIZE(sizes));
+ EXPECT(segs[2].log == 3);
+ EXPECT(segs[2].start == 5);
+ EXPECT(segs[2].end == 6);
+
+ EXPECT(segs[1].log == 2);
+ EXPECT(segs[1].start == 2);
+ EXPECT(segs[1].end == 5);
+ reftable_free(segs);
+}
+
+static void test_sizes_to_segments_empty(void)
+{
+ uint64_t sizes[0];
+
+ int seglen = 0;
+ struct segment *segs =
+ sizes_to_segments(&seglen, sizes, ARRAY_SIZE(sizes));
+ EXPECT(seglen == 0);
+ reftable_free(segs);
+}
+
+static void test_sizes_to_segments_all_equal(void)
+{
+ uint64_t sizes[] = { 5, 5 };
+
+ int seglen = 0;
+ struct segment *segs =
+ sizes_to_segments(&seglen, sizes, ARRAY_SIZE(sizes));
+ EXPECT(seglen == 1);
+ EXPECT(segs[0].start == 0);
+ EXPECT(segs[0].end == 2);
+ reftable_free(segs);
+}
+
+static void test_suggest_compaction_segment(void)
+{
+ uint64_t sizes[] = { 128, 64, 17, 16, 9, 9, 9, 16, 16 };
+ /* .................0 1 2 3 4 5 6 */
+ struct segment min =
+ suggest_compaction_segment(sizes, ARRAY_SIZE(sizes));
+ EXPECT(min.start == 2);
+ EXPECT(min.end == 7);
+}
+
+static void test_suggest_compaction_segment_nothing(void)
+{
+ uint64_t sizes[] = { 64, 32, 16, 8, 4, 2 };
+ struct segment result =
+ suggest_compaction_segment(sizes, ARRAY_SIZE(sizes));
+ EXPECT(result.start == result.end);
+}
+
+static void test_reflog_expire(void)
+{
+ char dir[256] = "/tmp/stack.test_reflog_expire.XXXXXX";
+ struct reftable_write_options cfg = { 0 };
+ struct reftable_stack *st = NULL;
+ struct reftable_log_record logs[20] = { { NULL } };
+ int N = ARRAY_SIZE(logs) - 1;
+ int i = 0;
+ int err;
+ struct reftable_log_expiry_config expiry = {
+ .time = 10,
+ };
+ struct reftable_log_record log = { NULL };
+
+ EXPECT(mkdtemp(dir));
+
+ err = reftable_new_stack(&st, dir, cfg);
+ EXPECT_ERR(err);
+
+ for (i = 1; i <= N; i++) {
+ char buf[256];
+ snprintf(buf, sizeof(buf), "branch%02d", i);
+
+ logs[i].refname = xstrdup(buf);
+ logs[i].update_index = i;
+ logs[i].time = i;
+ logs[i].new_hash = reftable_malloc(SHA1_SIZE);
+ logs[i].email = xstrdup("identity@invalid");
+ set_test_hash(logs[i].new_hash, i);
+ }
+
+ for (i = 1; i <= N; i++) {
+ struct write_log_arg arg = {
+ .log = &logs[i],
+ .update_index = reftable_stack_next_update_index(st),
+ };
+ int err = reftable_stack_add(st, &write_test_log, &arg);
+ EXPECT_ERR(err);
+ }
+
+ err = reftable_stack_compact_all(st, NULL);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_compact_all(st, &expiry);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_read_log(st, logs[9].refname, &log);
+ EXPECT(err == 1);
+
+ err = reftable_stack_read_log(st, logs[11].refname, &log);
+ EXPECT_ERR(err);
+
+ expiry.min_update_index = 15;
+ err = reftable_stack_compact_all(st, &expiry);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_read_log(st, logs[14].refname, &log);
+ EXPECT(err == 1);
+
+ err = reftable_stack_read_log(st, logs[16].refname, &log);
+ EXPECT_ERR(err);
+
+ /* cleanup */
+ reftable_stack_destroy(st);
+ for (i = 0; i <= N; i++) {
+ reftable_log_record_release(&logs[i]);
+ }
+ clear_dir(dir);
+ reftable_log_record_release(&log);
+}
+
+static int write_nothing(struct reftable_writer *wr, void *arg)
+{
+ reftable_writer_set_limits(wr, 1, 1);
+ return 0;
+}
+
+static void test_empty_add(void)
+{
+ struct reftable_write_options cfg = { 0 };
+ struct reftable_stack *st = NULL;
+ int err;
+ char dir[256] = "/tmp/stack_test.XXXXXX";
+ struct reftable_stack *st2 = NULL;
+
+ EXPECT(mkdtemp(dir));
+
+ err = reftable_new_stack(&st, dir, cfg);
+ EXPECT_ERR(err);
+
+ err = reftable_stack_add(st, &write_nothing, NULL);
+ EXPECT_ERR(err);
+
+ err = reftable_new_stack(&st2, dir, cfg);
+ EXPECT_ERR(err);
+ clear_dir(dir);
+ reftable_stack_destroy(st);
+ reftable_stack_destroy(st2);
+}
+
+static void test_reftable_stack_auto_compaction(void)
+{
+ struct reftable_write_options cfg = { 0 };
+ struct reftable_stack *st = NULL;
+ char dir[256] = "/tmp/stack_test.XXXXXX";
+ int err, i;
+ int N = 100;
+ EXPECT(mkdtemp(dir));
+
+ err = reftable_new_stack(&st, dir, cfg);
+ EXPECT_ERR(err);
+
+ for (i = 0; i < N; i++) {
+ char name[100];
+ struct reftable_ref_record ref = {
+ .refname = name,
+ .update_index = reftable_stack_next_update_index(st),
+ .target = "master",
+ };
+ snprintf(name, sizeof(name), "branch%04d", i);
+
+ err = reftable_stack_add(st, &write_test_ref, &ref);
+ EXPECT_ERR(err);
+
+ EXPECT(i < 3 || st->merged->stack_len < 2 * fastlog2(i));
+ }
+
+ EXPECT(reftable_stack_compaction_stats(st)->entries_written <
+ (uint64_t)(N * fastlog2(N)));
+
+ reftable_stack_destroy(st);
+ clear_dir(dir);
+}
+
+int stack_test_main(int argc, const char *argv[])
+{
+ test_reftable_stack_uptodate();
+ test_reftable_stack_transaction_api();
+ test_reftable_stack_hash_id();
+ test_sizes_to_segments_all_equal();
+ test_reftable_stack_auto_compaction();
+ test_reftable_stack_validate_refname();
+ test_reftable_stack_update_index_check();
+ test_reftable_stack_lock_failure();
+ test_reftable_stack_log_normalize();
+ test_reftable_stack_tombstone();
+ test_reftable_stack_add_one();
+ test_empty_add();
+ test_reflog_expire();
+ test_suggest_compaction_segment();
+ test_suggest_compaction_segment_nothing();
+ test_sizes_to_segments();
+ test_sizes_to_segments_empty();
+ test_log2();
+ test_parse_names();
+ test_read_file();
+ test_names_equal();
+ test_reftable_stack_add();
+ return 0;
+}
diff --git a/t/helper/test-reftable.c b/t/helper/test-reftable.c
index fdf9258673..3b702f4855 100644
--- a/t/helper/test-reftable.c
+++ b/t/helper/test-reftable.c
@@ -5,8 +5,11 @@ int cmd__reftable(int argc, const char **argv)
{
basics_test_main(argc, argv);
block_test_main(argc, argv);
+ merged_test_main(argc, argv);
record_test_main(argc, argv);
+ refname_test_main(argc, argv);
reftable_test_main(argc, argv);
+ stack_test_main(argc, argv);
tree_test_main(argc, argv);
return 0;
}
--
gitgitgadget
Han-Wen Nienhuys via GitGitGadget <gitgitgadget@gmail.com>