[PATCH v4 06/12] t: make the sha1 test-tool helper generic

["brian m. carlson" <sandals@xxxxxxxxxxxxxxxxxxxx>]

Since we're going to have multiple hash algorithms to test, it makes
sense to share as much of the test code as possible.  Convert the sha1
helper for the test-tool to be generic and move it out into its own
module.  This will allow us to share most of this code with our NewHash
implementation.

Signed-off-by: brian m. carlson <sandals@xxxxxxxxxxxxxxxxxxxx>
---
 Makefile                              |  1 +
 t/helper/{test-sha1.c => test-hash.c} | 19 +++++-----
 t/helper/test-sha1.c                  | 52 +--------------------------
 t/helper/test-tool.h                  |  2 ++
 4 files changed, 14 insertions(+), 60 deletions(-)
 copy t/helper/{test-sha1.c => test-hash.c} (65%)

diff --git a/Makefile b/Makefile
index d18ab0fe78..81dc9ac819 100644
--- a/Makefile
+++ b/Makefile
@@ -714,6 +714,7 @@ TEST_BUILTINS_OBJS += test-dump-split-index.o
 TEST_BUILTINS_OBJS += test-dump-untracked-cache.o
 TEST_BUILTINS_OBJS += test-example-decorate.o
 TEST_BUILTINS_OBJS += test-genrandom.o
+TEST_BUILTINS_OBJS += test-hash.o
 TEST_BUILTINS_OBJS += test-hashmap.o
 TEST_BUILTINS_OBJS += test-index-version.o
 TEST_BUILTINS_OBJS += test-json-writer.o
diff --git a/t/helper/test-sha1.c b/t/helper/test-hash.c
similarity index 65%
copy from t/helper/test-sha1.c
copy to t/helper/test-hash.c
index 1ba0675c75..0a31de66f3 100644
--- a/t/helper/test-sha1.c
+++ b/t/helper/test-hash.c
@@ -1,13 +1,14 @@
 #include "test-tool.h"
 #include "cache.h"
 
-int cmd__sha1(int ac, const char **av)
+int cmd_hash_impl(int ac, const char **av, int algo)
 {
-	git_SHA_CTX ctx;
-	unsigned char sha1[20];
+	git_hash_ctx ctx;
+	unsigned char hash[GIT_MAX_HEXSZ];
 	unsigned bufsz = 8192;
 	int binary = 0;
 	char *buffer;
+	const struct git_hash_algo *algop = &hash_algos[algo];
 
 	if (ac == 2) {
 		if (!strcmp(av[1], "-b"))
@@ -26,7 +27,7 @@ int cmd__sha1(int ac, const char **av)
 			die("OOPS");
 	}
 
-	git_SHA1_Init(&ctx);
+	algop->init_fn(&ctx);
 
 	while (1) {
 		ssize_t sz, this_sz;
@@ -38,20 +39,20 @@ int cmd__sha1(int ac, const char **av)
 			if (sz == 0)
 				break;
 			if (sz < 0)
-				die_errno("test-sha1");
+				die_errno("test-hash");
 			this_sz += sz;
 			cp += sz;
 			room -= sz;
 		}
 		if (this_sz == 0)
 			break;
-		git_SHA1_Update(&ctx, buffer, this_sz);
+		algop->update_fn(&ctx, buffer, this_sz);
 	}
-	git_SHA1_Final(sha1, &ctx);
+	algop->final_fn(hash, &ctx);
 
 	if (binary)
-		fwrite(sha1, 1, 20, stdout);
+		fwrite(hash, 1, algop->rawsz, stdout);
 	else
-		puts(sha1_to_hex(sha1));
+		puts(hash_to_hex_algop(hash, algop));
 	exit(0);
 }
diff --git a/t/helper/test-sha1.c b/t/helper/test-sha1.c
index 1ba0675c75..d860c387c3 100644
--- a/t/helper/test-sha1.c
+++ b/t/helper/test-sha1.c
@@ -3,55 +3,5 @@
 
 int cmd__sha1(int ac, const char **av)
 {
-	git_SHA_CTX ctx;
-	unsigned char sha1[20];
-	unsigned bufsz = 8192;
-	int binary = 0;
-	char *buffer;
-
-	if (ac == 2) {
-		if (!strcmp(av[1], "-b"))
-			binary = 1;
-		else
-			bufsz = strtoul(av[1], NULL, 10) * 1024 * 1024;
-	}
-
-	if (!bufsz)
-		bufsz = 8192;
-
-	while ((buffer = malloc(bufsz)) == NULL) {
-		fprintf(stderr, "bufsz %u is too big, halving...\n", bufsz);
-		bufsz /= 2;
-		if (bufsz < 1024)
-			die("OOPS");
-	}
-
-	git_SHA1_Init(&ctx);
-
-	while (1) {
-		ssize_t sz, this_sz;
-		char *cp = buffer;
-		unsigned room = bufsz;
-		this_sz = 0;
-		while (room) {
-			sz = xread(0, cp, room);
-			if (sz == 0)
-				break;
-			if (sz < 0)
-				die_errno("test-sha1");
-			this_sz += sz;
-			cp += sz;
-			room -= sz;
-		}
-		if (this_sz == 0)
-			break;
-		git_SHA1_Update(&ctx, buffer, this_sz);
-	}
-	git_SHA1_Final(sha1, &ctx);
-
-	if (binary)
-		fwrite(sha1, 1, 20, stdout);
-	else
-		puts(sha1_to_hex(sha1));
-	exit(0);
+	return cmd_hash_impl(ac, av, GIT_HASH_SHA1);
 }
diff --git a/t/helper/test-tool.h b/t/helper/test-tool.h
index e4890566da..29ac7b0b0d 100644
--- a/t/helper/test-tool.h
+++ b/t/helper/test-tool.h
@@ -50,4 +50,6 @@ int cmd__windows_named_pipe(int argc, const char **argv);
 #endif
 int cmd__write_cache(int argc, const char **argv);
 
+int cmd_hash_impl(int ac, const char **av, int algo);
+
 #endif