Use uint32_t for all packed object counts.

As we permit up to 2^32-1 objects in a single packfile we cannot
use a signed int to represent the object offset within a packfile,
after 2^31-1 objects we will start seeing negative indexes and
error out or compute bad addresses within the mmap'd index.

This is a minor cleanup that does not introduce any significant
logic changes.  It is roach free.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>

builtin-fsck.c

@@ -632,7 +632,7 @@ int cmd_fsck(int argc, char **argv, const char *prefix)
 			verify_pack(p, 0);
 
 		for (p = packed_git; p; p = p->next) {
-			int num = num_packed_objects(p);
+			uint32_t i, num = num_packed_objects(p);
 			for (i = 0; i < num; i++) {
 				unsigned char sha1[20];
 				nth_packed_object_sha1(p, i, sha1);

cache.h

@@ -425,8 +425,8 @@ extern void pack_report(void);
 extern unsigned char* use_pack(struct packed_git *, struct pack_window **, unsigned long, unsigned int *);
 extern void unuse_pack(struct pack_window **);
 extern struct packed_git *add_packed_git(char *, int, int);
-extern int num_packed_objects(const struct packed_git *p);
-extern int nth_packed_object_sha1(const struct packed_git *, int, unsigned char*);
+extern uint32_t num_packed_objects(const struct packed_git *p);
+extern int nth_packed_object_sha1(const struct packed_git *, uint32_t, unsigned char*);
 extern unsigned long find_pack_entry_one(const unsigned char *, struct packed_git *);
 extern void *unpack_entry(struct packed_git *, unsigned long, enum object_type *, unsigned long *);
 extern unsigned long unpack_object_header_gently(const unsigned char *buf, unsigned long len, enum object_type *type, unsigned long *sizep);

pack-check.c

@@ -9,7 +9,8 @@ static int verify_packfile(struct packed_git *p,
 	SHA_CTX ctx;
 	unsigned char sha1[20];
 	unsigned long offset = 0, pack_sig = p->pack_size - 20;
-	int nr_objects, err, i;
+	uint32_t nr_objects, i;
+	int err;
 
 	/* Note that the pack header checks are actually performed by
 	 * use_pack when it first opens the pack file.  If anything
@@ -40,7 +41,7 @@ static int verify_packfile(struct packed_git *p,
 	 * we do not do scan-streaming check on the pack file.
 	 */
 	nr_objects = num_packed_objects(p);
-	for (i = err = 0; i < nr_objects; i++) {
+	for (i = 0, err = 0; i < nr_objects; i++) {
 		unsigned char sha1[20];
 		void *data;
 		enum object_type type;
@@ -74,8 +75,7 @@ static int verify_packfile(struct packed_git *p,
 
 static void show_pack_info(struct packed_git *p)
 {
-	int nr_objects, i;
-	unsigned int chain_histogram[MAX_CHAIN];
+	uint32_t nr_objects, i, chain_histogram[MAX_CHAIN];
 
 	nr_objects = num_packed_objects(p);
 	memset(chain_histogram, 0, sizeof(chain_histogram));

sha1_file.c

@@ -437,7 +437,7 @@ static int check_packed_git_idx(const char *path,
 	void *idx_map;
 	uint32_t *index;
 	unsigned long idx_size;
-	int nr, i;
+	uint32_t nr, i;
 	int fd = open(path, O_RDONLY);
 	struct stat st;
 	if (fd < 0)
@@ -472,7 +472,7 @@ static int check_packed_git_idx(const char *path,
 
 	nr = 0;
 	for (i = 0; i < 256; i++) {
-		unsigned int n = ntohl(index[i]);
+		uint32_t n = ntohl(index[i]);
 		if (n < nr) {
 			munmap(idx_map, idx_size);
 			return error("non-monotonic index %s", path);
@@ -1339,17 +1339,17 @@ void *unpack_entry(struct packed_git *p, unsigned long obj_offset,
 	return data;
 }
 
-int num_packed_objects(const struct packed_git *p)
+uint32_t num_packed_objects(const struct packed_git *p)
 {
 	/* See check_packed_git_idx() */
 	return (p->index_size - 20 - 20 - 4*256) / 24;
 }
 
-int nth_packed_object_sha1(const struct packed_git *p, int n,
+int nth_packed_object_sha1(const struct packed_git *p, uint32_t n,
 			   unsigned char* sha1)
 {
 	void *index = p->index_base + 256;
-	if (n < 0 || num_packed_objects(p) <= n)
+	if (num_packed_objects(p) <= n)
 		return -1;
 	hashcpy(sha1, (unsigned char *) index + (24 * n) + 4);
 	return 0;

sha1_name.c

@@ -76,10 +76,10 @@ static int find_short_packed_object(int len, const unsigned char *match, unsigne
 
 	prepare_packed_git();
 	for (p = packed_git; p && found < 2; p = p->next) {
-		unsigned num = num_packed_objects(p);
-		unsigned first = 0, last = num;
+		uint32_t num = num_packed_objects(p);
+		uint32_t first = 0, last = num;
 		while (first < last) {
-			unsigned mid = (first + last) / 2;
+			uint32_t mid = (first + last) / 2;
 			unsigned char now[20];
 			int cmp;