diff mbox series

[v3,05/16] reftable: utility functions

Message ID 987d1d186fd68d604268f9a66118b7f276094daf.1606419752.git.gitgitgadget@gmail.com (mailing list archive)
State Superseded
Headers show
Series reftable library | expand

Commit Message

Han-Wen Nienhuys Nov. 26, 2020, 7:42 p.m. UTC
From: Han-Wen Nienhuys <hanwen@google.com>

This commit provides basic utility classes for the reftable library.

Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
---
 Makefile                     |  24 +++++-
 reftable/basics.c            | 144 +++++++++++++++++++++++++++++++++++
 reftable/basics.h            |  56 ++++++++++++++
 reftable/basics_test.c       |  56 ++++++++++++++
 reftable/compat.h            |  48 ++++++++++++
 reftable/publicbasics.c      |  58 ++++++++++++++
 reftable/reftable-malloc.h   |  20 +++++
 reftable/reftable-tests.h    |  22 ++++++
 reftable/system.h            |  32 ++++++++
 reftable/test_framework.c    |  23 ++++++
 reftable/test_framework.h    |  48 ++++++++++++
 t/helper/test-reftable.c     |   9 +++
 t/helper/test-tool.c         |   3 +-
 t/helper/test-tool.h         |   1 +
 t/t0032-reftable-unittest.sh |  14 ++++
 15 files changed, 554 insertions(+), 4 deletions(-)
 create mode 100644 reftable/basics.c
 create mode 100644 reftable/basics.h
 create mode 100644 reftable/basics_test.c
 create mode 100644 reftable/compat.h
 create mode 100644 reftable/publicbasics.c
 create mode 100644 reftable/reftable-malloc.h
 create mode 100644 reftable/reftable-tests.h
 create mode 100644 reftable/system.h
 create mode 100644 reftable/test_framework.c
 create mode 100644 reftable/test_framework.h
 create mode 100644 t/helper/test-reftable.c
 create mode 100755 t/t0032-reftable-unittest.sh

Comments

Felipe Contreras Nov. 27, 2020, 10:18 a.m. UTC | #1
On Fri, Nov 27, 2020 at 2:42 AM Han-Wen Nienhuys via GitGitGadget
<gitgitgadget@gmail.com> wrote:

> +int binsearch(size_t sz, int (*f)(size_t k, void *args), void *args)
> +{
> +       size_t lo = 0;
> +       size_t hi = sz;

Is there anything wrong with:

  size_t lo = 0, hi = sz;

> +       /* invariant: (hi == sz) || f(hi) == true
> +          (lo == 0 && f(0) == true) || fi(lo) == false
> +        */

This doesn't follow the multi-line format. And perhaps English would be better.

> +       while (hi - lo > 1) {
> +               size_t mid = lo + (hi - lo) / 2;
> +
> +               int val = f(mid, args);
> +               if (val) {
> +                       hi = mid;
> +               } else {
> +                       lo = mid;
> +               }

Unnecessary braces are frowned upon. Also, why store the value if you
are not going to use it later?

if (f(mid, args))
  hi = mid;
else
  lo = mid;

> +       }
> +
> +       if (lo == 0) {

if (!lo)

> +               if (f(0, args)) {
> +                       return 0;
> +               } else {
> +                       return 1;
> +               }

return f(0, args) ? 0 : 1;

Or just:

return !f(0, args);

> +       }
> +
> +       return hi;

It would be much clearer to just do:

if (lo)
  return hi;
else
  return !f(0, args);

> +}
> +
> +void free_names(char **a)
> +{
> +       char **p = a;
> +       if (p == NULL) {
> +               return;
> +       }

Once again:

  if (!p)
    return;

> +       while (*p) {
> +               reftable_free(*p);
> +               p++;
> +       }

This is the same thing as:

  if (!a)
    return;

  for (p = a; *p; p++)
    reftable_free(*p);

> +int names_length(char **names)
> +{
> +       int len = 0;
> +       char **p = names;
> +       while (*p) {
> +               p++;
> +               len++;
> +       }
> +       return len;
> +}

Is there any need to keep track of len? It's always p - names.

This should do it:

  char **p;
  for (p = names; *p; p++);
  return p - names;

> +void parse_names(char *buf, int size, char ***namesp)
> +{
> +       char **names = NULL;
> +       size_t names_cap = 0;
> +       size_t names_len = 0;
> +
> +       char *p = buf;
> +       char *end = buf + size;
> +       while (p < end) {

Yet another while that can be a for:

  for (p = buf; p < end; p = next + 1)

> +               char *next = strchr(p, '\n');
> +               if (next != NULL) {
> +                       *next = 0;
> +               } else {
> +                       next = end;
> +               }

if (next)
  *next = 0;
else
  next = end;

> +               if (p < next) {

Or just:

  if (p >= next)
    continue;

> +                       if (names_len == names_cap) {
> +                               names_cap = 2 * names_cap + 1;
> +                               names = reftable_realloc(
> +                                       names, names_cap * sizeof(char *));

sizeof(*names);

> +                       }
> +                       names[names_len++] = xstrdup(p);
> +               }
> +               p = next + 1;
> +       }
> +
> +       if (names_len == names_cap) {
> +               names_cap = 2 * names_cap + 1;
> +               names = reftable_realloc(names, names_cap * sizeof(char *));
> +       }

This is repeated, maybe a macro like ALLOC_GROW(), or literally ALLOC_GROW().

> +       names[names_len] = NULL;
> +       *namesp = names;
> +}
> +
> +int names_equal(char **a, char **b)
> +{
> +       while (*a && *b) {
> +               if (strcmp(*a, *b)) {
> +                       return 0;
> +               }
> +
> +               a++;
> +               b++;
> +       }

Again:

  for (; *a && *b, a++, b++) {
    if (strcmp(*a, *b)
      return 0;
  }

But instead of moving multiple pointers:

  for (i = 0; a[i] && b[i], i++) {
    if (strcmp(a[i], b[i])
      return 0;
  }

> +int common_prefix_size(struct strbuf *a, struct strbuf *b)
> +{
> +       int p = 0;
> +       while (p < a->len && p < b->len) {

Once again, this can easily be a for.

> +               if (a->buf[p] != b->buf[p]) {
> +                       break;
> +               }
> +               p++;
> +       }
> +
> +       return p;
> +}

Cheers.
Ævar Arnfjörð Bjarmason Nov. 27, 2020, 10:33 a.m. UTC | #2
On Thu, Nov 26 2020, Han-Wen Nienhuys via GitGitGadget wrote:

> From: Han-Wen Nienhuys <hanwen@google.com>
>
> This commit provides basic utility classes for the reftable library.

Re Johannes's comments in v2
(https://lore.kernel.org/git/nycvar.QRO.7.76.6.2010021557570.50@tvgsbejvaqbjf.bet/)
about strbuf.c etc. being duplicated I see that's gone now.

It seems you did some version of my suggestion in
https://lore.kernel.org/git/873625i9tc.fsf@evledraar.gmail.com/ of
factoring out that code, except here:

> [...]
> +#ifdef REFTABLE_STANDALONE
> +
> +/* functions that git-core provides, for standalone compilation */
> +#include <stdint.h>
> +
> +uint64_t get_be64(void *in);
> +void put_be64(void *out, uint64_t i);

It's unclear whether that's an omission, or needed for some reason (is
git.git ever going to have REFTABLE_STANDALONE=true?

The update shellscript is also gone from v2->v3, is that out of tree now
somewhere? How does one test with the upstream code & presumably do some
munging on it to make it diff-able with what's going to be in git.git?

It would be really useful to have that sort of info/summary in the cover
letter between serieses. It's not that I mind e.g. having some of this
REFTABLE_STANDALONE code here. Just having to do archaeology trying to
figure out changes in this rather large series...
diff mbox series

Patch

diff --git a/Makefile b/Makefile
index dd1cf41e00..5ce78772fd 100644
--- a/Makefile
+++ b/Makefile
@@ -732,6 +732,7 @@  TEST_BUILTINS_OBJS += test-read-cache.o
 TEST_BUILTINS_OBJS += test-read-graph.o
 TEST_BUILTINS_OBJS += test-read-midx.o
 TEST_BUILTINS_OBJS += test-ref-store.o
+TEST_BUILTINS_OBJS += test-reftable.o
 TEST_BUILTINS_OBJS += test-regex.o
 TEST_BUILTINS_OBJS += test-repository.o
 TEST_BUILTINS_OBJS += test-revision-walking.o
@@ -821,6 +822,8 @@  TEST_SHELL_PATH = $(SHELL_PATH)
 
 LIB_FILE = libgit.a
 XDIFF_LIB = xdiff/lib.a
+REFTABLE_LIB = reftable/libreftable.a
+REFTABLE_TEST_LIB = reftable/libreftable_test.a
 
 GENERATED_H += command-list.h
 GENERATED_H += config-list.h
@@ -1185,7 +1188,7 @@  THIRD_PARTY_SOURCES += compat/regex/%
 THIRD_PARTY_SOURCES += sha1collisiondetection/%
 THIRD_PARTY_SOURCES += sha1dc/%
 
-GITLIBS = common-main.o $(LIB_FILE) $(XDIFF_LIB)
+GITLIBS = common-main.o $(LIB_FILE) $(XDIFF_LIB) $(REFTABLE_LIB)
 EXTLIBS =
 
 GIT_USER_AGENT = git/$(GIT_VERSION)
@@ -2386,10 +2389,19 @@  XDIFF_OBJS += xdiff/xpatience.o
 XDIFF_OBJS += xdiff/xprepare.o
 XDIFF_OBJS += xdiff/xutils.o
 
+REFTABLE_OBJS += reftable/basics.o
+REFTABLE_OBJS += reftable/error.o
+REFTABLE_OBJS += reftable/publicbasics.o
+
+REFTABLE_TEST_OBJS += reftable/test_framework.o
+REFTABLE_TEST_OBJS += reftable/basics_test.o
+
 TEST_OBJS := $(patsubst %$X,%.o,$(TEST_PROGRAMS)) $(patsubst %,t/helper/%,$(TEST_BUILTINS_OBJS))
 OBJECTS := $(LIB_OBJS) $(BUILTIN_OBJS) $(PROGRAM_OBJS) $(TEST_OBJS) \
 	$(XDIFF_OBJS) \
 	$(FUZZ_OBJS) \
+	$(REFTABLE_OBJS) \
+	$(REFTABLE_TEST_OBJS) \
 	common-main.o \
 	git.o
 ifndef NO_CURL
@@ -2541,6 +2553,12 @@  $(LIB_FILE): $(LIB_OBJS)
 $(XDIFF_LIB): $(XDIFF_OBJS)
 	$(QUIET_AR)$(RM) $@ && $(AR) $(ARFLAGS) $@ $^
 
+$(REFTABLE_LIB): $(REFTABLE_OBJS)
+	$(QUIET_AR)$(RM) $@ && $(AR) $(ARFLAGS) $@ $^
+
+$(REFTABLE_TEST_LIB): $(REFTABLE_TEST_OBJS)
+	$(QUIET_AR)$(RM) $@ && $(AR) $(ARFLAGS) $@ $^
+
 export DEFAULT_EDITOR DEFAULT_PAGER
 
 Documentation/GIT-EXCLUDED-PROGRAMS: FORCE
@@ -2822,7 +2840,7 @@  perf: all
 
 t/helper/test-tool$X: $(patsubst %,t/helper/%,$(TEST_BUILTINS_OBJS))
 
-t/helper/test-%$X: t/helper/test-%.o GIT-LDFLAGS $(GITLIBS)
+t/helper/test-%$X: t/helper/test-%.o GIT-LDFLAGS $(GITLIBS) $(REFTABLE_TEST_LIB)
 	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) $(filter %.a,$^) $(LIBS)
 
 check-sha1:: t/helper/test-tool$X
@@ -3151,7 +3169,7 @@  cocciclean:
 clean: profile-clean coverage-clean cocciclean
 	$(RM) *.res
 	$(RM) $(OBJECTS)
-	$(RM) $(LIB_FILE) $(XDIFF_LIB)
+	$(RM) $(LIB_FILE) $(XDIFF_LIB) $(REFTABLE_LIB) $(REFTABLE_TEST_LIB)
 	$(RM) $(ALL_PROGRAMS) $(SCRIPT_LIB) $(BUILT_INS) git$X
 	$(RM) $(TEST_PROGRAMS)
 	$(RM) $(FUZZ_PROGRAMS)
diff --git a/reftable/basics.c b/reftable/basics.c
new file mode 100644
index 0000000000..915c55e0ee
--- /dev/null
+++ b/reftable/basics.c
@@ -0,0 +1,144 @@ 
+/*
+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"
+
+void put_be24(uint8_t *out, uint32_t i)
+{
+	out[0] = (uint8_t)((i >> 16) & 0xff);
+	out[1] = (uint8_t)((i >> 8) & 0xff);
+	out[2] = (uint8_t)(i & 0xff);
+}
+
+uint32_t get_be24(uint8_t *in)
+{
+	return (uint32_t)(in[0]) << 16 | (uint32_t)(in[1]) << 8 |
+	       (uint32_t)(in[2]);
+}
+
+void put_be16(uint8_t *out, uint16_t i)
+{
+	out[0] = (uint8_t)((i >> 8) & 0xff);
+	out[1] = (uint8_t)(i & 0xff);
+}
+
+int binsearch(size_t sz, int (*f)(size_t k, void *args), void *args)
+{
+	size_t lo = 0;
+	size_t hi = sz;
+
+	/* invariant: (hi == sz) || f(hi) == true
+	   (lo == 0 && f(0) == true) || fi(lo) == false
+	 */
+	while (hi - lo > 1) {
+		size_t mid = lo + (hi - lo) / 2;
+
+		int val = f(mid, args);
+		if (val) {
+			hi = mid;
+		} else {
+			lo = mid;
+		}
+	}
+
+	if (lo == 0) {
+		if (f(0, args)) {
+			return 0;
+		} else {
+			return 1;
+		}
+	}
+
+	return hi;
+}
+
+void free_names(char **a)
+{
+	char **p = a;
+	if (p == NULL) {
+		return;
+	}
+	while (*p) {
+		reftable_free(*p);
+		p++;
+	}
+	reftable_free(a);
+}
+
+int names_length(char **names)
+{
+	int len = 0;
+	char **p = names;
+	while (*p) {
+		p++;
+		len++;
+	}
+	return len;
+}
+
+void parse_names(char *buf, int size, char ***namesp)
+{
+	char **names = NULL;
+	size_t names_cap = 0;
+	size_t names_len = 0;
+
+	char *p = buf;
+	char *end = buf + size;
+	while (p < end) {
+		char *next = strchr(p, '\n');
+		if (next != NULL) {
+			*next = 0;
+		} else {
+			next = end;
+		}
+		if (p < next) {
+			if (names_len == names_cap) {
+				names_cap = 2 * names_cap + 1;
+				names = reftable_realloc(
+					names, names_cap * sizeof(char *));
+			}
+			names[names_len++] = xstrdup(p);
+		}
+		p = next + 1;
+	}
+
+	if (names_len == names_cap) {
+		names_cap = 2 * names_cap + 1;
+		names = reftable_realloc(names, names_cap * sizeof(char *));
+	}
+
+	names[names_len] = NULL;
+	*namesp = names;
+}
+
+int names_equal(char **a, char **b)
+{
+	while (*a && *b) {
+		if (strcmp(*a, *b)) {
+			return 0;
+		}
+
+		a++;
+		b++;
+	}
+
+	return *a == *b;
+}
+
+int common_prefix_size(struct strbuf *a, struct strbuf *b)
+{
+	int p = 0;
+	while (p < a->len && p < b->len) {
+		if (a->buf[p] != b->buf[p]) {
+			break;
+		}
+		p++;
+	}
+
+	return p;
+}
diff --git a/reftable/basics.h b/reftable/basics.h
new file mode 100644
index 0000000000..0948926637
--- /dev/null
+++ b/reftable/basics.h
@@ -0,0 +1,56 @@ 
+/*
+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 BASICS_H
+#define BASICS_H
+
+/*
+ * miscellaneous utilities that are not provided by Git.
+ */
+
+#include "system.h"
+
+/* Bigendian en/decoding of integers */
+
+void put_be24(uint8_t *out, uint32_t i);
+uint32_t get_be24(uint8_t *in);
+void put_be16(uint8_t *out, uint16_t i);
+
+/*
+  find smallest index i in [0, sz) at which f(i) is true, assuming
+  that f is ascending. Return sz if f(i) is false for all indices.
+*/
+int binsearch(size_t sz, int (*f)(size_t k, void *args), void *args);
+
+/*
+  Frees a NULL terminated array of malloced strings. The array itself is also
+  freed.
+ */
+void free_names(char **a);
+
+/* parse a newline separated list of names. Empty names are discarded. */
+void parse_names(char *buf, int size, char ***namesp);
+
+/* compares two NULL-terminated arrays of strings. */
+int names_equal(char **a, char **b);
+
+/* returns the array size of a NULL-terminated array of strings. */
+int names_length(char **names);
+
+/* Allocation routines; they invoke the functions set through
+ * reftable_set_alloc() */
+void *reftable_malloc(size_t sz);
+void *reftable_realloc(void *p, size_t sz);
+void reftable_free(void *p);
+void *reftable_calloc(size_t sz);
+
+/* Find the longest shared prefix size of `a` and `b` */
+struct strbuf;
+int common_prefix_size(struct strbuf *a, struct strbuf *b);
+
+#endif
diff --git a/reftable/basics_test.c b/reftable/basics_test.c
new file mode 100644
index 0000000000..593d3e608a
--- /dev/null
+++ b/reftable/basics_test.c
@@ -0,0 +1,56 @@ 
+/*
+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 "basics.h"
+#include "test_framework.h"
+#include "reftable-tests.h"
+
+struct binsearch_args {
+	int key;
+	int *arr;
+};
+
+static int binsearch_func(size_t i, void *void_args)
+{
+	struct binsearch_args *args = (struct binsearch_args *)void_args;
+
+	return args->key < args->arr[i];
+}
+
+static void test_binsearch(void)
+{
+	int arr[] = { 2, 4, 6, 8, 10 };
+	size_t sz = ARRAY_SIZE(arr);
+	struct binsearch_args args = {
+		.arr = arr,
+	};
+
+	int i = 0;
+	for (i = 1; i < 11; i++) {
+		int res;
+		args.key = i;
+		res = binsearch(sz, &binsearch_func, &args);
+
+		if (res < sz) {
+			EXPECT(args.key < arr[res]);
+			if (res > 0) {
+				EXPECT(args.key >= arr[res - 1]);
+			}
+		} else {
+			EXPECT(args.key == 10 || args.key == 11);
+		}
+	}
+}
+
+int basics_test_main(int argc, const char *argv[])
+{
+	test_binsearch();
+	return 0;
+}
diff --git a/reftable/compat.h b/reftable/compat.h
new file mode 100644
index 0000000000..a765c57e96
--- /dev/null
+++ b/reftable/compat.h
@@ -0,0 +1,48 @@ 
+/*
+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 COMPAT_H
+#define COMPAT_H
+
+#include "system.h"
+
+#ifdef REFTABLE_STANDALONE
+
+/* functions that git-core provides, for standalone compilation */
+#include <stdint.h>
+
+uint64_t get_be64(void *in);
+void put_be64(void *out, uint64_t i);
+
+void put_be32(void *out, uint32_t i);
+uint32_t get_be32(uint8_t *in);
+
+uint16_t get_be16(uint8_t *in);
+
+#define ARRAY_SIZE(a) sizeof((a)) / sizeof((a)[0])
+#define FREE_AND_NULL(x)          \
+	do {                      \
+		reftable_free(x); \
+		(x) = NULL;       \
+	} while (0)
+#define QSORT(arr, n, cmp) qsort(arr, n, sizeof(arr[0]), cmp)
+#define SWAP(a, b)                              \
+	{                                       \
+		char tmp[sizeof(a)];            \
+		assert(sizeof(a) == sizeof(b)); \
+		memcpy(&tmp[0], &a, sizeof(a)); \
+		memcpy(&a, &b, sizeof(a));      \
+		memcpy(&b, &tmp[0], sizeof(a)); \
+	}
+
+char *xstrdup(const char *s);
+
+void sleep_millisec(int millisecs);
+
+#endif
+#endif
diff --git a/reftable/publicbasics.c b/reftable/publicbasics.c
new file mode 100644
index 0000000000..25639f61af
--- /dev/null
+++ b/reftable/publicbasics.c
@@ -0,0 +1,58 @@ 
+/*
+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 "reftable-malloc.h"
+
+#include "basics.h"
+#include "system.h"
+
+static void *(*reftable_malloc_ptr)(size_t sz) = &malloc;
+static void *(*reftable_realloc_ptr)(void *, size_t) = &realloc;
+static void (*reftable_free_ptr)(void *) = &free;
+
+void *reftable_malloc(size_t sz)
+{
+	return (*reftable_malloc_ptr)(sz);
+}
+
+void *reftable_realloc(void *p, size_t sz)
+{
+	return (*reftable_realloc_ptr)(p, sz);
+}
+
+void reftable_free(void *p)
+{
+	reftable_free_ptr(p);
+}
+
+void *reftable_calloc(size_t sz)
+{
+	void *p = reftable_malloc(sz);
+	memset(p, 0, sz);
+	return p;
+}
+
+void reftable_set_alloc(void *(*malloc)(size_t),
+			void *(*realloc)(void *, size_t), void (*free)(void *))
+{
+	reftable_malloc_ptr = malloc;
+	reftable_realloc_ptr = realloc;
+	reftable_free_ptr = free;
+}
+
+int hash_size(uint32_t id)
+{
+	switch (id) {
+	case 0:
+	case SHA1_ID:
+		return SHA1_SIZE;
+	case SHA256_ID:
+		return SHA256_SIZE;
+	}
+	abort();
+}
diff --git a/reftable/reftable-malloc.h b/reftable/reftable-malloc.h
new file mode 100644
index 0000000000..f3571b5f4f
--- /dev/null
+++ b/reftable/reftable-malloc.h
@@ -0,0 +1,20 @@ 
+/*
+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_H
+#define REFTABLE_H
+
+#include <stddef.h>
+
+/*
+  Overrides the functions to use for memory management.
+ */
+void reftable_set_alloc(void *(*malloc)(size_t),
+			void *(*realloc)(void *, size_t), void (*free)(void *));
+
+#endif
diff --git a/reftable/reftable-tests.h b/reftable/reftable-tests.h
new file mode 100644
index 0000000000..5e7698ae65
--- /dev/null
+++ b/reftable/reftable-tests.h
@@ -0,0 +1,22 @@ 
+/*
+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_TESTS_H
+#define REFTABLE_TESTS_H
+
+int basics_test_main(int argc, const char **argv);
+int block_test_main(int argc, const char **argv);
+int merged_test_main(int argc, const char **argv);
+int record_test_main(int argc, const char **argv);
+int refname_test_main(int argc, const char **argv);
+int reftable_test_main(int argc, const char **argv);
+int stack_test_main(int argc, const char **argv);
+int tree_test_main(int argc, const char **argv);
+int reftable_dump_main(int argc, char *const *argv);
+
+#endif
diff --git a/reftable/system.h b/reftable/system.h
new file mode 100644
index 0000000000..07277ca062
--- /dev/null
+++ b/reftable/system.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 SYSTEM_H
+#define SYSTEM_H
+
+#include "git-compat-util.h"
+#include "strbuf.h"
+
+#include <zlib.h>
+
+struct strbuf;
+/* In git, this is declared in dir.h */
+int remove_dir_recursively(struct strbuf *path, int flags);
+
+#define SHA1_ID 0x73686131
+#define SHA256_ID 0x73323536
+#define SHA1_SIZE 20
+#define SHA256_SIZE 32
+
+/* This is uncompress2, which is only available in zlib as of 2017.
+ */
+int uncompress_return_consumed(Bytef *dest, uLongf *destLen,
+			       const Bytef *source, uLong *sourceLen);
+int hash_size(uint32_t id);
+
+#endif
diff --git a/reftable/test_framework.c b/reftable/test_framework.c
new file mode 100644
index 0000000000..a5ff4e2a2d
--- /dev/null
+++ b/reftable/test_framework.c
@@ -0,0 +1,23 @@ 
+/*
+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 "test_framework.h"
+
+#include "basics.h"
+
+void set_test_hash(uint8_t *p, int i)
+{
+	memset(p, (uint8_t)i, hash_size(SHA1_ID));
+}
+
+int strbuf_add_void(void *b, const void *data, size_t sz)
+{
+	strbuf_add((struct strbuf *)b, data, sz);
+	return sz;
+}
diff --git a/reftable/test_framework.h b/reftable/test_framework.h
new file mode 100644
index 0000000000..18eec29aba
--- /dev/null
+++ b/reftable/test_framework.h
@@ -0,0 +1,48 @@ 
+/*
+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 TEST_FRAMEWORK_H
+#define TEST_FRAMEWORK_H
+
+#include "system.h"
+#include "reftable-error.h"
+
+#define EXPECT_ERR(c)                                                  \
+	if (c != 0) {                                                  \
+		fflush(stderr);                                        \
+		fflush(stdout);                                        \
+		fprintf(stderr, "%s: %d: error == %d (%s), want 0\n",  \
+			__FILE__, __LINE__, c, reftable_error_str(c)); \
+		abort();                                               \
+	}
+
+#define EXPECT_STREQ(a, b)                                               \
+	if (strcmp(a, b)) {                                              \
+		fflush(stderr);                                          \
+		fflush(stdout);                                          \
+		fprintf(stderr, "%s:%d: %s (%s) != %s (%s)\n", __FILE__, \
+			__LINE__, #a, a, #b, b);                         \
+		abort();                                                 \
+	}
+
+#define EXPECT(c)                                                          \
+	if (!(c)) {                                                        \
+		fflush(stderr);                                            \
+		fflush(stdout);                                            \
+		fprintf(stderr, "%s: %d: failed assertion %s\n", __FILE__, \
+			__LINE__, #c);                                     \
+		abort();                                                   \
+	}
+
+void set_test_hash(uint8_t *p, int i);
+
+/* Like strbuf_add, but suitable for passing to reftable_new_writer
+ */
+int strbuf_add_void(void *b, const void *data, size_t sz);
+
+#endif
diff --git a/t/helper/test-reftable.c b/t/helper/test-reftable.c
new file mode 100644
index 0000000000..3b58e423e7
--- /dev/null
+++ b/t/helper/test-reftable.c
@@ -0,0 +1,9 @@ 
+#include "reftable/reftable-tests.h"
+#include "test-tool.h"
+
+int cmd__reftable(int argc, const char **argv)
+{
+	basics_test_main(argc, argv);
+
+	return 0;
+}
diff --git a/t/helper/test-tool.c b/t/helper/test-tool.c
index 9d6d14d929..0208a0a41c 100644
--- a/t/helper/test-tool.c
+++ b/t/helper/test-tool.c
@@ -48,13 +48,14 @@  static struct test_cmd cmds[] = {
 	{ "path-utils", cmd__path_utils },
 	{ "pkt-line", cmd__pkt_line },
 	{ "prio-queue", cmd__prio_queue },
-	{ "proc-receive", cmd__proc_receive},
+	{ "proc-receive", cmd__proc_receive },
 	{ "progress", cmd__progress },
 	{ "reach", cmd__reach },
 	{ "read-cache", cmd__read_cache },
 	{ "read-graph", cmd__read_graph },
 	{ "read-midx", cmd__read_midx },
 	{ "ref-store", cmd__ref_store },
+	{ "reftable", cmd__reftable },
 	{ "regex", cmd__regex },
 	{ "repository", cmd__repository },
 	{ "revision-walking", cmd__revision_walking },
diff --git a/t/helper/test-tool.h b/t/helper/test-tool.h
index a6470ff62c..1de39ce5b5 100644
--- a/t/helper/test-tool.h
+++ b/t/helper/test-tool.h
@@ -44,6 +44,7 @@  int cmd__read_cache(int argc, const char **argv);
 int cmd__read_graph(int argc, const char **argv);
 int cmd__read_midx(int argc, const char **argv);
 int cmd__ref_store(int argc, const char **argv);
+int cmd__reftable(int argc, const char **argv);
 int cmd__regex(int argc, const char **argv);
 int cmd__repository(int argc, const char **argv);
 int cmd__revision_walking(int argc, const char **argv);
diff --git a/t/t0032-reftable-unittest.sh b/t/t0032-reftable-unittest.sh
new file mode 100755
index 0000000000..10e21a0590
--- /dev/null
+++ b/t/t0032-reftable-unittest.sh
@@ -0,0 +1,14 @@ 
+#!/bin/sh
+#
+# Copyright (c) 2020 Google LLC
+#
+
+test_description='reftable unittests'
+
+. ./test-lib.sh
+
+test_expect_success 'unittests' '
+       test-tool reftable
+'
+
+test_done