Commit ccc4feb5 authored by Linus Torvalds's avatar Linus Torvalds

Convert the index file reading/writing to use network byte order.

This allows using a git tree over NFS with different byte order, and
makes it possible to just copy a fully populated repository and have
the end result immediately usable (needing just a refresh to update
the stat information).
parent 27de946d
......@@ -10,6 +10,7 @@
#include <string.h>
#include <errno.h>
#include <sys/mman.h>
#include <netinet/in.h>
#include <openssl/sha.h>
#include <zlib.h>
......@@ -24,9 +25,9 @@
#define CACHE_SIGNATURE 0x44495243 /* "DIRC" */
struct cache_header {
unsigned int signature;
unsigned int version;
unsigned int entries;
unsigned int hdr_signature;
unsigned int hdr_version;
unsigned int hdr_entries;
unsigned char sha1[20];
};
......@@ -44,18 +45,21 @@ struct cache_time {
* dev/ino/uid/gid/size are also just tracked to the low 32 bits
* Again - this is just a (very strong in practice) heuristic that
* the inode hasn't changed.
*
* We save the fields in big-endian order to allow using the
* index file over NFS transparently.
*/
struct cache_entry {
struct cache_time ctime;
struct cache_time mtime;
unsigned int st_dev;
unsigned int st_ino;
unsigned int st_mode;
unsigned int st_uid;
unsigned int st_gid;
unsigned int st_size;
struct cache_time ce_ctime;
struct cache_time ce_mtime;
unsigned int ce_dev;
unsigned int ce_ino;
unsigned int ce_mode;
unsigned int ce_uid;
unsigned int ce_gid;
unsigned int ce_size;
unsigned char sha1[20];
unsigned short namelen;
unsigned short ce_namelen;
char name[0];
};
......@@ -67,7 +71,8 @@ unsigned int active_nr, active_alloc;
#define DEFAULT_DB_ENVIRONMENT ".git/objects"
#define cache_entry_size(len) ((offsetof(struct cache_entry,name) + (len) + 8) & ~7)
#define ce_size(ce) cache_entry_size((ce)->namelen)
#define ce_namelen(ce) ntohs((ce)->ce_namelen)
#define ce_size(ce) cache_entry_size(ce_namelen(ce))
#define alloc_nr(x) (((x)+16)*3/2)
......
......@@ -77,7 +77,7 @@ static int write_entry(struct cache_entry *ce)
return error("checkout-cache: unable to read sha1 file of %s (%s)",
ce->name, sha1_to_hex(ce->sha1));
}
fd = create_file(ce->name, ce->st_mode);
fd = create_file(ce->name, ntohl(ce->ce_mode));
if (fd < 0) {
free(new);
return error("checkout-cache: unable to create %s (%s)",
......
......@@ -283,30 +283,32 @@ int cache_match_stat(struct cache_entry *ce, struct stat *st)
{
unsigned int changed = 0;
/* nsec seems unreliable - not all filesystems support it, so
* as long as it is in the inode cache you get right nsec
* but after it gets flushed, you get zero nsec. */
if (ce->mtime.sec != (unsigned int)st->st_mtim.tv_sec
#ifdef NSEC
|| ce->mtime.nsec != (unsigned int)st->st_mtim.tv_nsec
#endif
)
if (ce->ce_mtime.sec != htonl(st->st_mtime))
changed |= MTIME_CHANGED;
if (ce->ctime.sec != (unsigned int)st->st_ctim.tv_sec
if (ce->ce_ctime.sec != htonl(st->st_ctime))
changed |= CTIME_CHANGED;
#ifdef NSEC
|| ce->ctime.nsec != (unsigned int)st->st_ctim.tv_nsec
#endif
)
/*
* nsec seems unreliable - not all filesystems support it, so
* as long as it is in the inode cache you get right nsec
* but after it gets flushed, you get zero nsec.
*/
if (ce->ce_mtime.nsec != htonl(st->st_mtim.tv_nsec)
changed |= MTIME_CHANGED;
if (ce->ce_ctime.nsec != htonl(st->st_ctim.tv_nsec)
changed |= CTIME_CHANGED;
if (ce->st_uid != (unsigned int)st->st_uid ||
ce->st_gid != (unsigned int)st->st_gid)
#endif
if (ce->ce_uid != htonl(st->st_uid) ||
ce->ce_gid != htonl(st->st_gid))
changed |= OWNER_CHANGED;
if (ce->st_mode != (unsigned int)st->st_mode)
if (ce->ce_mode != htonl(st->st_mode))
changed |= MODE_CHANGED;
if (ce->st_dev != (unsigned int)st->st_dev ||
ce->st_ino != (unsigned int)st->st_ino)
if (ce->ce_dev != htonl(st->st_dev) ||
ce->ce_ino != htonl(st->st_ino))
changed |= INODE_CHANGED;
if (ce->st_size != (unsigned int)st->st_size)
if (ce->ce_size != htonl(st->st_size))
changed |= DATA_CHANGED;
return changed;
}
......@@ -335,7 +337,7 @@ int cache_name_pos(const char *name, int namelen)
while (last > first) {
int next = (last + first) >> 1;
struct cache_entry *ce = active_cache[next];
int cmp = cache_name_compare(name, namelen, ce->name, ce->namelen);
int cmp = cache_name_compare(name, namelen, ce->name, ce_namelen(ce));
if (!cmp)
return next;
if (cmp < 0) {
......@@ -362,7 +364,7 @@ int add_cache_entry(struct cache_entry *ce, int ok_to_add)
{
int pos;
pos = cache_name_pos(ce->name, ce->namelen);
pos = cache_name_pos(ce->name, ce_namelen(ce));
/* existing match? Just replace it */
if (pos >= 0) {
......@@ -393,9 +395,9 @@ static int verify_hdr(struct cache_header *hdr, unsigned long size)
SHA_CTX c;
unsigned char sha1[20];
if (hdr->signature != CACHE_SIGNATURE)
if (hdr->hdr_signature != htonl(CACHE_SIGNATURE))
return error("bad signature");
if (hdr->version != 1)
if (hdr->hdr_version != htonl(1))
return error("bad version");
SHA1_Init(&c);
SHA1_Update(&c, hdr, offsetof(struct cache_header, sha1));
......@@ -443,12 +445,12 @@ int read_cache(void)
if (verify_hdr(hdr, size) < 0)
goto unmap;
active_nr = hdr->entries;
active_nr = ntohl(hdr->hdr_entries);
active_alloc = alloc_nr(active_nr);
active_cache = calloc(active_alloc, sizeof(struct cache_entry *));
offset = sizeof(*hdr);
for (i = 0; i < hdr->entries; i++) {
for (i = 0; i < active_nr; i++) {
struct cache_entry *ce = map + offset;
offset = offset + ce_size(ce);
active_cache[i] = ce;
......@@ -467,9 +469,9 @@ int write_cache(int newfd, struct cache_entry **cache, int entries)
struct cache_header hdr;
int i;
hdr.signature = CACHE_SIGNATURE;
hdr.version = 1;
hdr.entries = entries;
hdr.hdr_signature = htonl(CACHE_SIGNATURE);
hdr.hdr_version = htonl(1);
hdr.hdr_entries = htonl(entries);
SHA1_Init(&c);
SHA1_Update(&c, &hdr, offsetof(struct cache_header, sha1));
......
......@@ -13,8 +13,8 @@ static int read_one_entry(unsigned char *sha1, const char *base, int baselen, co
memset(ce, 0, size);
ce->st_mode = mode;
ce->namelen = baselen + len;
ce->ce_mode = htonl(mode);
ce->ce_namelen = htons(baselen + len);
memcpy(ce->name, base, baselen);
memcpy(ce->name + baselen, pathname, len+1);
memcpy(ce->sha1, sha1, 20);
......
......@@ -90,7 +90,7 @@ int main(int argc, char **argv)
changed = cache_match_stat(ce, &st);
if (!changed)
continue;
printf("%.*s: ", ce->namelen, ce->name);
printf("%.*s: ", ce_namelen(ce), ce->name);
for (n = 0; n < 20; n++)
printf("%02x", ce->sha1[n]);
printf("\n");
......
......@@ -68,18 +68,17 @@ static int index_fd(const char *path, int namelen, struct cache_entry *ce, int f
*/
static void fill_stat_cache_info(struct cache_entry *ce, struct stat *st)
{
ce->ctime.sec = st->st_ctime;
ce->ce_ctime.sec = htonl(st->st_ctime);
ce->ce_mtime.sec = htonl(st->st_mtime);
#ifdef NSEC
ce->ctime.nsec = st->st_ctim.tv_nsec;
ce->ce_ctime.nsec = htonl(st->st_ctim.tv_nsec);
ce->ce_mtime.nsec = htonl(st->st_mtim.tv_nsec);
#endif
ce->mtime.sec = st->st_mtime;
#ifdef NSEC
ce->mtime.nsec = st->st_mtim.tv_nsec;
#endif
ce->st_dev = st->st_dev;
ce->st_ino = st->st_ino;
ce->st_uid = st->st_uid;
ce->st_gid = st->st_gid;
ce->ce_dev = htonl(st->st_dev);
ce->ce_ino = htonl(st->st_ino);
ce->ce_uid = htonl(st->st_uid);
ce->ce_gid = htonl(st->st_gid);
ce->ce_size = htonl(st->st_size);
}
static int add_file_to_cache(char *path)
......@@ -107,9 +106,8 @@ static int add_file_to_cache(char *path)
memset(ce, 0, size);
memcpy(ce->name, path, namelen);
fill_stat_cache_info(ce, &st);
ce->st_mode = st.st_mode;
ce->st_size = st.st_size;
ce->namelen = namelen;
ce->ce_mode = htonl(st.st_mode);
ce->ce_namelen = htons(namelen);
if (index_fd(path, namelen, ce, fd, &st) < 0)
return -1;
......@@ -190,7 +188,6 @@ static struct cache_entry *refresh_entry(struct cache_entry *ce)
updated = malloc(size);
memcpy(updated, ce, size);
fill_stat_cache_info(updated, &st);
updated->st_size = st.st_size;
return updated;
}
......
......@@ -45,7 +45,7 @@ static int write_tree(struct cache_entry **cachep, int maxentries, const char *b
do {
struct cache_entry *ce = cachep[nr];
const char *pathname = ce->name, *filename, *dirname;
int pathlen = ce->namelen, entrylen;
int pathlen = ce_namelen(ce), entrylen;
unsigned char *sha1;
unsigned int mode;
......@@ -54,7 +54,7 @@ static int write_tree(struct cache_entry **cachep, int maxentries, const char *b
break;
sha1 = ce->sha1;
mode = ce->st_mode;
mode = ntohl(ce->ce_mode);
/* Do we have _further_ subdirectories? */
filename = pathname + baselen;
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment