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-rw-r--r--read-cache.c396
1 files changed, 287 insertions, 109 deletions
diff --git a/read-cache.c b/read-cache.c
index 0a641034ce..1df6adf0bf 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -12,6 +12,8 @@
#include "commit.h"
#include "blob.h"
#include "resolve-undo.h"
+#include "strbuf.h"
+#include "varint.h"
static struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int really);
@@ -157,16 +159,6 @@ static int ce_modified_check_fs(struct cache_entry *ce, struct stat *st)
return 0;
}
-static int is_empty_blob_sha1(const unsigned char *sha1)
-{
- static const unsigned char empty_blob_sha1[20] = {
- 0xe6,0x9d,0xe2,0x9b,0xb2,0xd1,0xd6,0x43,0x4b,0x8b,
- 0x29,0xae,0x77,0x5a,0xd8,0xc2,0xe4,0x8c,0x53,0x91
- };
-
- return !hashcmp(sha1, empty_blob_sha1);
-}
-
static int ce_match_stat_basic(struct cache_entry *ce, struct stat *st)
{
unsigned int changed = 0;
@@ -726,11 +718,12 @@ static int verify_dotfile(const char *rest)
* has already been discarded, we now test
* the rest.
*/
- switch (*rest) {
+
/* "." is not allowed */
- case '\0': case '/':
+ if (*rest == '\0' || is_dir_sep(*rest))
return 0;
+ switch (*rest) {
/*
* ".git" followed by NUL or slash is bad. This
* shares the path end test with the ".." case.
@@ -743,7 +736,7 @@ static int verify_dotfile(const char *rest)
rest += 2;
/* fallthrough */
case '.':
- if (rest[1] == '\0' || rest[1] == '/')
+ if (rest[1] == '\0' || is_dir_sep(rest[1]))
return 0;
}
return 1;
@@ -753,23 +746,19 @@ int verify_path(const char *path)
{
char c;
+ if (has_dos_drive_prefix(path))
+ return 0;
+
goto inside;
for (;;) {
if (!c)
return 1;
- if (c == '/') {
+ if (is_dir_sep(c)) {
inside:
c = *path++;
- switch (c) {
- default:
- continue;
- case '/': case '\0':
- break;
- case '.':
- if (verify_dotfile(path))
- continue;
- }
- return 0;
+ if ((c == '.' && !verify_dotfile(path)) ||
+ is_dir_sep(c) || c == '\0')
+ return 0;
}
c = *path++;
}
@@ -1004,7 +993,8 @@ int add_index_entry(struct index_state *istate, struct cache_entry *ce, int opti
*/
static struct cache_entry *refresh_cache_ent(struct index_state *istate,
struct cache_entry *ce,
- unsigned int options, int *err)
+ unsigned int options, int *err,
+ int *changed_ret)
{
struct stat st;
struct cache_entry *updated;
@@ -1036,6 +1026,8 @@ static struct cache_entry *refresh_cache_ent(struct index_state *istate,
}
changed = ie_match_stat(istate, ce, &st, options);
+ if (changed_ret)
+ *changed_ret = changed;
if (!changed) {
/*
* The path is unchanged. If we were told to ignore
@@ -1105,19 +1097,31 @@ int refresh_index(struct index_state *istate, unsigned int flags, const char **p
int first = 1;
int in_porcelain = (flags & REFRESH_IN_PORCELAIN);
unsigned int options = really ? CE_MATCH_IGNORE_VALID : 0;
- const char *needs_update_fmt;
- const char *needs_merge_fmt;
-
- needs_update_fmt = (in_porcelain ? "M\t%s\n" : "%s: needs update\n");
- needs_merge_fmt = (in_porcelain ? "U\t%s\n" : "%s: needs merge\n");
+ const char *modified_fmt;
+ const char *deleted_fmt;
+ const char *typechange_fmt;
+ const char *added_fmt;
+ const char *unmerged_fmt;
+
+ modified_fmt = (in_porcelain ? "M\t%s\n" : "%s: needs update\n");
+ deleted_fmt = (in_porcelain ? "D\t%s\n" : "%s: needs update\n");
+ typechange_fmt = (in_porcelain ? "T\t%s\n" : "%s needs update\n");
+ added_fmt = (in_porcelain ? "A\t%s\n" : "%s needs update\n");
+ unmerged_fmt = (in_porcelain ? "U\t%s\n" : "%s: needs merge\n");
for (i = 0; i < istate->cache_nr; i++) {
struct cache_entry *ce, *new;
int cache_errno = 0;
+ int changed = 0;
+ int filtered = 0;
ce = istate->cache[i];
if (ignore_submodules && S_ISGITLINK(ce->ce_mode))
continue;
+ if (pathspec &&
+ !match_pathspec(pathspec, ce->name, ce_namelen(ce), 0, seen))
+ filtered = 1;
+
if (ce_stage(ce)) {
while ((i < istate->cache_nr) &&
! strcmp(istate->cache[i]->name, ce->name))
@@ -1125,18 +1129,22 @@ int refresh_index(struct index_state *istate, unsigned int flags, const char **p
i--;
if (allow_unmerged)
continue;
- show_file(needs_merge_fmt, ce->name, in_porcelain, &first, header_msg);
+ if (!filtered)
+ show_file(unmerged_fmt, ce->name, in_porcelain,
+ &first, header_msg);
has_errors = 1;
continue;
}
- if (pathspec && !match_pathspec(pathspec, ce->name, strlen(ce->name), 0, seen))
+ if (filtered)
continue;
- new = refresh_cache_ent(istate, ce, options, &cache_errno);
+ new = refresh_cache_ent(istate, ce, options, &cache_errno, &changed);
if (new == ce)
continue;
if (!new) {
+ const char *fmt;
+
if (not_new && cache_errno == ENOENT)
continue;
if (really && cache_errno == EINVAL) {
@@ -1148,7 +1156,17 @@ int refresh_index(struct index_state *istate, unsigned int flags, const char **p
}
if (quiet)
continue;
- show_file(needs_update_fmt, ce->name, in_porcelain, &first, header_msg);
+
+ if (cache_errno == ENOENT)
+ fmt = deleted_fmt;
+ else if (ce->ce_flags & CE_INTENT_TO_ADD)
+ fmt = added_fmt; /* must be before other checks */
+ else if (changed & TYPE_CHANGED)
+ fmt = typechange_fmt;
+ else
+ fmt = modified_fmt;
+ show_file(fmt,
+ ce->name, in_porcelain, &first, header_msg);
has_errors = 1;
continue;
}
@@ -1160,18 +1178,77 @@ int refresh_index(struct index_state *istate, unsigned int flags, const char **p
static struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int really)
{
- return refresh_cache_ent(&the_index, ce, really, NULL);
+ return refresh_cache_ent(&the_index, ce, really, NULL, NULL);
}
+
+/*****************************************************************
+ * Index File I/O
+ *****************************************************************/
+
+#define INDEX_FORMAT_DEFAULT 3
+
+/*
+ * 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 ondisk_cache_entry {
+ struct cache_time ctime;
+ struct cache_time mtime;
+ unsigned int dev;
+ unsigned int ino;
+ unsigned int mode;
+ unsigned int uid;
+ unsigned int gid;
+ unsigned int size;
+ unsigned char sha1[20];
+ unsigned short flags;
+ char name[FLEX_ARRAY]; /* more */
+};
+
+/*
+ * This struct is used when CE_EXTENDED bit is 1
+ * The struct must match ondisk_cache_entry exactly from
+ * ctime till flags
+ */
+struct ondisk_cache_entry_extended {
+ struct cache_time ctime;
+ struct cache_time mtime;
+ unsigned int dev;
+ unsigned int ino;
+ unsigned int mode;
+ unsigned int uid;
+ unsigned int gid;
+ unsigned int size;
+ unsigned char sha1[20];
+ unsigned short flags;
+ unsigned short flags2;
+ char name[FLEX_ARRAY]; /* more */
+};
+
+/* These are only used for v3 or lower */
+#define align_flex_name(STRUCT,len) ((offsetof(struct STRUCT,name) + (len) + 8) & ~7)
+#define ondisk_cache_entry_size(len) align_flex_name(ondisk_cache_entry,len)
+#define ondisk_cache_entry_extended_size(len) align_flex_name(ondisk_cache_entry_extended,len)
+#define ondisk_ce_size(ce) (((ce)->ce_flags & CE_EXTENDED) ? \
+ ondisk_cache_entry_extended_size(ce_namelen(ce)) : \
+ ondisk_cache_entry_size(ce_namelen(ce)))
+
static int verify_hdr(struct cache_header *hdr, unsigned long size)
{
git_SHA_CTX c;
unsigned char sha1[20];
+ int hdr_version;
if (hdr->hdr_signature != htonl(CACHE_SIGNATURE))
return error("bad signature");
- if (hdr->hdr_version != htonl(2) && hdr->hdr_version != htonl(3))
- return error("bad index version");
+ hdr_version = ntohl(hdr->hdr_version);
+ if (hdr_version < 2 || 4 < hdr_version)
+ return error("bad index version %d", hdr_version);
git_SHA1_Init(&c);
git_SHA1_Update(&c, hdr, size - 20);
git_SHA1_Final(sha1, &c);
@@ -1205,63 +1282,115 @@ int read_index(struct index_state *istate)
return read_index_from(istate, get_index_file());
}
-static void convert_from_disk(struct ondisk_cache_entry *ondisk, struct cache_entry *ce)
+#ifndef NEEDS_ALIGNED_ACCESS
+#define ntoh_s(var) ntohs(var)
+#define ntoh_l(var) ntohl(var)
+#else
+static inline uint16_t ntoh_s_force_align(void *p)
+{
+ uint16_t x;
+ memcpy(&x, p, sizeof(x));
+ return ntohs(x);
+}
+static inline uint32_t ntoh_l_force_align(void *p)
+{
+ uint32_t x;
+ memcpy(&x, p, sizeof(x));
+ return ntohl(x);
+}
+#define ntoh_s(var) ntoh_s_force_align(&(var))
+#define ntoh_l(var) ntoh_l_force_align(&(var))
+#endif
+
+static struct cache_entry *cache_entry_from_ondisk(struct ondisk_cache_entry *ondisk,
+ unsigned int flags,
+ const char *name,
+ size_t len)
+{
+ struct cache_entry *ce = xmalloc(cache_entry_size(len));
+
+ ce->ce_ctime.sec = ntoh_l(ondisk->ctime.sec);
+ ce->ce_mtime.sec = ntoh_l(ondisk->mtime.sec);
+ ce->ce_ctime.nsec = ntoh_l(ondisk->ctime.nsec);
+ ce->ce_mtime.nsec = ntoh_l(ondisk->mtime.nsec);
+ ce->ce_dev = ntoh_l(ondisk->dev);
+ ce->ce_ino = ntoh_l(ondisk->ino);
+ ce->ce_mode = ntoh_l(ondisk->mode);
+ ce->ce_uid = ntoh_l(ondisk->uid);
+ ce->ce_gid = ntoh_l(ondisk->gid);
+ ce->ce_size = ntoh_l(ondisk->size);
+ ce->ce_flags = flags;
+ hashcpy(ce->sha1, ondisk->sha1);
+ memcpy(ce->name, name, len);
+ ce->name[len] = '\0';
+ return ce;
+}
+
+/*
+ * Adjacent cache entries tend to share the leading paths, so it makes
+ * sense to only store the differences in later entries. In the v4
+ * on-disk format of the index, each on-disk cache entry stores the
+ * number of bytes to be stripped from the end of the previous name,
+ * and the bytes to append to the result, to come up with its name.
+ */
+static unsigned long expand_name_field(struct strbuf *name, const char *cp_)
+{
+ const unsigned char *ep, *cp = (const unsigned char *)cp_;
+ size_t len = decode_varint(&cp);
+
+ if (name->len < len)
+ die("malformed name field in the index");
+ strbuf_remove(name, name->len - len, len);
+ for (ep = cp; *ep; ep++)
+ ; /* find the end */
+ strbuf_add(name, cp, ep - cp);
+ return (const char *)ep + 1 - cp_;
+}
+
+static struct cache_entry *create_from_disk(struct ondisk_cache_entry *ondisk,
+ unsigned long *ent_size,
+ struct strbuf *previous_name)
{
+ struct cache_entry *ce;
size_t len;
const char *name;
+ unsigned int flags;
- ce->ce_ctime.sec = ntohl(ondisk->ctime.sec);
- ce->ce_mtime.sec = ntohl(ondisk->mtime.sec);
- ce->ce_ctime.nsec = ntohl(ondisk->ctime.nsec);
- ce->ce_mtime.nsec = ntohl(ondisk->mtime.nsec);
- ce->ce_dev = ntohl(ondisk->dev);
- ce->ce_ino = ntohl(ondisk->ino);
- ce->ce_mode = ntohl(ondisk->mode);
- ce->ce_uid = ntohl(ondisk->uid);
- ce->ce_gid = ntohl(ondisk->gid);
- ce->ce_size = ntohl(ondisk->size);
/* On-disk flags are just 16 bits */
- ce->ce_flags = ntohs(ondisk->flags);
-
- hashcpy(ce->sha1, ondisk->sha1);
-
- len = ce->ce_flags & CE_NAMEMASK;
+ flags = ntoh_s(ondisk->flags);
+ len = flags & CE_NAMEMASK;
- if (ce->ce_flags & CE_EXTENDED) {
+ if (flags & CE_EXTENDED) {
struct ondisk_cache_entry_extended *ondisk2;
int extended_flags;
ondisk2 = (struct ondisk_cache_entry_extended *)ondisk;
- extended_flags = ntohs(ondisk2->flags2) << 16;
+ extended_flags = ntoh_s(ondisk2->flags2) << 16;
/* We do not yet understand any bit out of CE_EXTENDED_FLAGS */
if (extended_flags & ~CE_EXTENDED_FLAGS)
die("Unknown index entry format %08x", extended_flags);
- ce->ce_flags |= extended_flags;
+ flags |= extended_flags;
name = ondisk2->name;
}
else
name = ondisk->name;
- if (len == CE_NAMEMASK)
- len = strlen(name);
- /*
- * NEEDSWORK: If the original index is crafted, this copy could
- * go unchecked.
- */
- memcpy(ce->name, name, len + 1);
-}
-
-static inline size_t estimate_cache_size(size_t ondisk_size, unsigned int entries)
-{
- long per_entry;
-
- per_entry = sizeof(struct cache_entry) - sizeof(struct ondisk_cache_entry);
-
- /*
- * Alignment can cause differences. This should be "alignof", but
- * since that's a gcc'ism, just use the size of a pointer.
- */
- per_entry += sizeof(void *);
- return ondisk_size + entries*per_entry;
+ if (!previous_name) {
+ /* v3 and earlier */
+ if (len == CE_NAMEMASK)
+ len = strlen(name);
+ ce = cache_entry_from_ondisk(ondisk, flags, name, len);
+
+ *ent_size = ondisk_ce_size(ce);
+ } else {
+ unsigned long consumed;
+ consumed = expand_name_field(previous_name, name);
+ ce = cache_entry_from_ondisk(ondisk, flags,
+ previous_name->buf,
+ previous_name->len);
+
+ *ent_size = (name - ((char *)ondisk)) + consumed;
+ }
+ return ce;
}
/* remember to discard_cache() before reading a different cache! */
@@ -1269,10 +1398,11 @@ int read_index_from(struct index_state *istate, const char *path)
{
int fd, i;
struct stat st;
- unsigned long src_offset, dst_offset;
+ unsigned long src_offset;
struct cache_header *hdr;
void *mmap;
size_t mmap_size;
+ struct strbuf previous_name_buf = STRBUF_INIT, *previous_name;
errno = EBUSY;
if (istate->initialized)
@@ -1305,33 +1435,30 @@ int read_index_from(struct index_state *istate, const char *path)
if (verify_hdr(hdr, mmap_size) < 0)
goto unmap;
+ istate->version = ntohl(hdr->hdr_version);
istate->cache_nr = ntohl(hdr->hdr_entries);
istate->cache_alloc = alloc_nr(istate->cache_nr);
istate->cache = xcalloc(istate->cache_alloc, sizeof(struct cache_entry *));
-
- /*
- * The disk format is actually larger than the in-memory format,
- * due to space for nsec etc, so even though the in-memory one
- * has room for a few more flags, we can allocate using the same
- * index size
- */
- istate->alloc = xmalloc(estimate_cache_size(mmap_size, istate->cache_nr));
istate->initialized = 1;
+ if (istate->version == 4)
+ previous_name = &previous_name_buf;
+ else
+ previous_name = NULL;
+
src_offset = sizeof(*hdr);
- dst_offset = 0;
for (i = 0; i < istate->cache_nr; i++) {
struct ondisk_cache_entry *disk_ce;
struct cache_entry *ce;
+ unsigned long consumed;
disk_ce = (struct ondisk_cache_entry *)((char *)mmap + src_offset);
- ce = (struct cache_entry *)((char *)istate->alloc + dst_offset);
- convert_from_disk(disk_ce, ce);
+ ce = create_from_disk(disk_ce, &consumed, previous_name);
set_index_entry(istate, i, ce);
- src_offset += ondisk_ce_size(ce);
- dst_offset += ce_size(ce);
+ src_offset += consumed;
}
+ strbuf_release(&previous_name_buf);
istate->timestamp.sec = st.st_mtime;
istate->timestamp.nsec = ST_MTIME_NSEC(st);
@@ -1364,11 +1491,15 @@ unmap:
int is_index_unborn(struct index_state *istate)
{
- return (!istate->cache_nr && !istate->alloc && !istate->timestamp.sec);
+ return (!istate->cache_nr && !istate->timestamp.sec);
}
int discard_index(struct index_state *istate)
{
+ int i;
+
+ for (i = 0; i < istate->cache_nr; i++)
+ free(istate->cache[i]);
resolve_undo_clear_index(istate);
istate->cache_nr = 0;
istate->cache_changed = 0;
@@ -1377,8 +1508,6 @@ int discard_index(struct index_state *istate)
istate->name_hash_initialized = 0;
free_hash(&istate->name_hash);
cache_tree_free(&(istate->cache_tree));
- free(istate->alloc);
- istate->alloc = NULL;
istate->initialized = 0;
/* no need to throw away allocated active_cache */
@@ -1513,13 +1642,10 @@ static void ce_smudge_racily_clean_entry(struct cache_entry *ce)
}
}
-static int ce_write_entry(git_SHA_CTX *c, int fd, struct cache_entry *ce)
+/* Copy miscellaneous fields but not the name */
+static char *copy_cache_entry_to_ondisk(struct ondisk_cache_entry *ondisk,
+ struct cache_entry *ce)
{
- int size = ondisk_ce_size(ce);
- struct ondisk_cache_entry *ondisk = xcalloc(1, size);
- char *name;
- int result;
-
ondisk->ctime.sec = htonl(ce->ce_ctime.sec);
ondisk->mtime.sec = htonl(ce->ce_mtime.sec);
ondisk->ctime.nsec = htonl(ce->ce_ctime.nsec);
@@ -1536,11 +1662,52 @@ static int ce_write_entry(git_SHA_CTX *c, int fd, struct cache_entry *ce)
struct ondisk_cache_entry_extended *ondisk2;
ondisk2 = (struct ondisk_cache_entry_extended *)ondisk;
ondisk2->flags2 = htons((ce->ce_flags & CE_EXTENDED_FLAGS) >> 16);
- name = ondisk2->name;
+ return ondisk2->name;
+ }
+ else {
+ return ondisk->name;
+ }
+}
+
+static int ce_write_entry(git_SHA_CTX *c, int fd, struct cache_entry *ce,
+ struct strbuf *previous_name)
+{
+ int size;
+ struct ondisk_cache_entry *ondisk;
+ char *name;
+ int result;
+
+ if (!previous_name) {
+ size = ondisk_ce_size(ce);
+ ondisk = xcalloc(1, size);
+ name = copy_cache_entry_to_ondisk(ondisk, ce);
+ memcpy(name, ce->name, ce_namelen(ce));
+ } else {
+ int common, to_remove, prefix_size;
+ unsigned char to_remove_vi[16];
+ for (common = 0;
+ (ce->name[common] &&
+ common < previous_name->len &&
+ ce->name[common] == previous_name->buf[common]);
+ common++)
+ ; /* still matching */
+ to_remove = previous_name->len - common;
+ prefix_size = encode_varint(to_remove, to_remove_vi);
+
+ if (ce->ce_flags & CE_EXTENDED)
+ size = offsetof(struct ondisk_cache_entry_extended, name);
+ else
+ size = offsetof(struct ondisk_cache_entry, name);
+ size += prefix_size + (ce_namelen(ce) - common + 1);
+
+ ondisk = xcalloc(1, size);
+ name = copy_cache_entry_to_ondisk(ondisk, ce);
+ memcpy(name, to_remove_vi, prefix_size);
+ memcpy(name + prefix_size, ce->name + common, ce_namelen(ce) - common);
+
+ strbuf_splice(previous_name, common, to_remove,
+ ce->name + common, ce_namelen(ce) - common);
}
- else
- name = ondisk->name;
- memcpy(name, ce->name, ce_namelen(ce));
result = ce_write(c, fd, ondisk, size);
free(ondisk);
@@ -1576,10 +1743,11 @@ int write_index(struct index_state *istate, int newfd)
{
git_SHA_CTX c;
struct cache_header hdr;
- int i, err, removed, extended;
+ int i, err, removed, extended, hdr_version;
struct cache_entry **cache = istate->cache;
int entries = istate->cache_nr;
struct stat st;
+ struct strbuf previous_name_buf = STRBUF_INIT, *previous_name;
for (i = removed = extended = 0; i < entries; i++) {
if (cache[i]->ce_flags & CE_REMOVE)
@@ -1593,24 +1761,34 @@ int write_index(struct index_state *istate, int newfd)
}
}
+ if (!istate->version)
+ istate->version = INDEX_FORMAT_DEFAULT;
+
+ /* demote version 3 to version 2 when the latter suffices */
+ if (istate->version == 3 || istate->version == 2)
+ istate->version = extended ? 3 : 2;
+
+ hdr_version = istate->version;
+
hdr.hdr_signature = htonl(CACHE_SIGNATURE);
- /* for extended format, increase version so older git won't try to read it */
- hdr.hdr_version = htonl(extended ? 3 : 2);
+ hdr.hdr_version = htonl(hdr_version);
hdr.hdr_entries = htonl(entries - removed);
git_SHA1_Init(&c);
if (ce_write(&c, newfd, &hdr, sizeof(hdr)) < 0)
return -1;
+ previous_name = (hdr_version == 4) ? &previous_name_buf : NULL;
for (i = 0; i < entries; i++) {
struct cache_entry *ce = cache[i];
if (ce->ce_flags & CE_REMOVE)
continue;
if (!ce_uptodate(ce) && is_racy_timestamp(istate, ce))
ce_smudge_racily_clean_entry(ce);
- if (ce_write_entry(&c, newfd, ce) < 0)
+ if (ce_write_entry(&c, newfd, ce, previous_name) < 0)
return -1;
}
+ strbuf_release(&previous_name_buf);
/* Write extension data here */
if (istate->cache_tree) {
@@ -1663,7 +1841,7 @@ int read_index_unmerged(struct index_state *istate)
if (!ce_stage(ce))
continue;
unmerged = 1;
- len = strlen(ce->name);
+ len = ce_namelen(ce);
size = cache_entry_size(len);
new_ce = xcalloc(1, size);
memcpy(new_ce->name, ce->name, len);