diff --git a/cmd-mount.c b/cmd-mount.c
index 542d57e..10a0c5d 100644
--- a/cmd-mount.c
+++ b/cmd-mount.c
@@ -6,14 +6,13 @@
  *  See the file COPYING.
  */
 
-#define _GNU_SOURCE		/* for sigset(), canonicalize_file_name() */
+#include "cache.h"		/* from git core */
 #include "gitfs.h"
 #include "defaults.h"
 #include <sys/epoll.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <signal.h>
-#include "cache.h"		/* from git core */
 
 /* Set up git to read from the current directory */
 static int prepare_git_environment(void)
diff --git a/conf.c b/conf.c
index b0422ff..f0d6972 100644
--- a/conf.c
+++ b/conf.c
@@ -230,7 +230,7 @@ int validate_command_line_options_wcount(const struct gitcmd_option *list,
 	return 0;
 }
 
-static int gitfs_config_file_worker(const char *var, const char *val)
+static int gitfs_config_file_worker(const char *var, const char *val, void *cb)
 {
 	static const char prefix[] = { 'g', 'i', 't', 'f', 's', '.' };
 	int rv;
@@ -251,7 +251,7 @@ int gitfs_server_read_config(void)
 
 	/* If there's a normal git config file, read it */
 	if (stat("config", &dummy_st) == 0 &&
-	    git_config(gitfs_config_file_worker) != 0)
+	    git_config(gitfs_config_file_worker, NULL) != 0)
 		return -1;
 	/*
 	 * Now take all of the entries previously put into the "from_cmd_line"
diff --git a/gitfs.h b/gitfs.h
index f5fb578..f02af89 100644
--- a/gitfs.h
+++ b/gitfs.h
@@ -14,6 +14,7 @@
 #include <stdint.h>
 #include <unistd.h>
 #include <time.h>	/* for "struct timespec" */
+#include <stddef.h>
 
 #ifdef __GNUC__
 #define likely(x)	__builtin_expect(!!(x), 1)
diff --git a/gitobj.c b/gitobj.c
index 304d2b0..a08f4d2 100644
--- a/gitobj.c
+++ b/gitobj.c
@@ -725,7 +725,7 @@ static int fill_gitobj_from_worker_result(struct gitobj *gobj,
 	if (unlikely(gobj->type != GFN_INCOMPLETE)) {
 		/* We already got parsed! */
 		assert(gobj->type == cmd->answer.open.type);
-		goto done;
+		goto done_nofree;
 	}
 	switch (cmd->answer.open.type) {
 	case GFN_DIR:
@@ -748,8 +748,6 @@ static int fill_gitobj_from_worker_result(struct gitobj *gobj,
 	default:
 		assert(0);
 	}
-    done:
-	free(cmd->answer.open.buf);
     done_nofree:
 	gobj->type = cmd->answer.open.type;
 	return ret;
diff --git a/gitworker.c b/gitworker.c
index 09e3fd7..604fb9f 100644
--- a/gitworker.c
+++ b/gitworker.c
@@ -44,7 +44,7 @@ static void gitwork_find_packname(struct gitwork_cmd *cmd)
 static int raw_resolve_reference(const unsigned char *obuf,
 				 unsigned char **nbufp, unsigned long *sizep,
 				 const char *ref_str, size_t reflen,
-				 char *type)
+				 enum object_type *type)
 {
 	struct gitobj_ptr nptr;
 
@@ -52,7 +52,7 @@ static int raw_resolve_reference(const unsigned char *obuf,
 	    0 != memcmp(obuf, ref_str, reflen) ||
 	    get_sha1_hex((const char *) &obuf[reflen], &nptr.sha1[0]) != 0)
 		return -ENOLINK;
-	*nbufp = read_sha1_file(&nptr.sha1[0], type, sizep);
+	*nbufp = read_sha1_file(nptr.sha1, type, sizep);
 	if (*nbufp == NULL)
 		return -ENOENT;
 	return 0;
@@ -68,17 +68,17 @@ static int raw_resolve_reference(const unsigned char *obuf,
 static int git_read(const struct gitobj_ptr *ptr,
 		    struct gitwork_open_result *ores)
 {
-	char type[20];
+	enum object_type type;
 	unsigned char *buf;
 	int res;
 
-	buf = read_sha1_file(&ptr->sha1[0], type, &ores->size);
+	buf = read_sha1_file(ptr->sha1, &type, &ores->size);
 	if (buf == NULL)
 		return -ENOENT;
 	ores->buf = buf;
-	if (0 == strcmp(type, "tag")) {
+	if (type == OBJ_TAG) {
 		res = resolve_reference(ores->buf, &buf,
-					&ores->size, "object", type);
+					&ores->size, "object", &type);
 		free(ores->buf);
 		if (res != 0) {
 			assert(res < 0);
@@ -86,9 +86,9 @@ static int git_read(const struct gitobj_ptr *ptr,
 		}
 		ores->buf = buf;
 	}
-	if (0 == strcmp(type, "commit")) {
+	if (type == OBJ_COMMIT) {
 		res = resolve_reference(ores->buf, &buf,
-					&ores->size, "tree", type);
+					&ores->size, "tree", &type);
 		free(ores->buf);
 		if (res != 0) {
 			assert(res < 0);
@@ -96,9 +96,9 @@ static int git_read(const struct gitobj_ptr *ptr,
 		}
 		ores->buf = buf;
 	}
-	if (0 == strcmp(type, "tree")) {
+	if (type == OBJ_TREE) {
 		ores->type = GFN_DIR;
-	} else if (0 == strcmp(type, "blob")) {
+	} else if (type == OBJ_BLOB) {
 		ores->type = GFN_FILE;
 		/* Note: this could actually turn out to be a symlink */
 	} else {
@@ -117,10 +117,10 @@ static void gitwork_object_info(struct gitwork_cmd *cmd)
 	 */
 	if (cmd->answer.open.type == GFN_FILE ||
 	    cmd->answer.open.type == GFN_SYMLINK) {
-		char type[20];
-		if (sha1_object_info(&cmd->gptr->sha1[0], type,
+		enum object_type type;
+		if (read_sha1_file(cmd->gptr->sha1, &type,
 				     &cmd->answer.open.size) == 0 &&
-		    0 == strcmp(type, "blob")) {
+		    type == OBJ_BLOB) {
 			cmd->error = 0;
 			cmd->answer.open.type = GFN_FILE;
 			cmd->answer.open.buf = NULL;
diff --git a/util.c b/util.c
index 4614898..3c2bc81 100644
--- a/util.c
+++ b/util.c
@@ -6,7 +6,7 @@
  *  See the file COPYING.
  */
 
-#define _GNU_SOURCE	/* for clock_gettime() */
+#include "cache.h"	/* for get_sha1_hex() */
 #include "gitfs.h"
 #include <stdio.h>
 #include <errno.h>
@@ -16,7 +16,6 @@
 #include <limits.h>
 #include <sys/mman.h>
 #include <sys/stat.h>
-#include "cache.h"	/* for get_sha1_hex() */
 
 int
 #ifdef __GNUC__