*
* Copyright (C) Linus Torvalds, 2005
*/
-#include <stdarg.h>
#include "cache.h"
struct cache_entry **active_cache = NULL;
-unsigned int active_nr = 0, active_alloc = 0;
+unsigned int active_nr = 0, active_alloc = 0, active_cache_changed = 0;
-int cache_match_stat(struct cache_entry *ce, struct stat *st)
+/*
+ * This only updates the "non-critical" parts of the directory
+ * cache, ie the parts that aren't tracked by GIT, and only used
+ * to validate the cache.
+ */
+void fill_stat_cache_info(struct cache_entry *ce, struct stat *st)
+{
+ ce->ce_ctime.sec = htonl(st->st_ctime);
+ ce->ce_mtime.sec = htonl(st->st_mtime);
+#ifdef USE_NSEC
+ ce->ce_ctime.nsec = htonl(st->st_ctim.tv_nsec);
+ ce->ce_mtime.nsec = htonl(st->st_mtim.tv_nsec);
+#endif
+ 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);
+}
+
+int ce_match_stat(struct cache_entry *ce, struct stat *st)
{
unsigned int changed = 0;
+ switch (ntohl(ce->ce_mode) & S_IFMT) {
+ case S_IFREG:
+ changed |= !S_ISREG(st->st_mode) ? TYPE_CHANGED : 0;
+ /* We consider only the owner x bit to be relevant for "mode changes" */
+ if (0100 & (ntohl(ce->ce_mode) ^ st->st_mode))
+ changed |= MODE_CHANGED;
+ break;
+ case S_IFLNK:
+ changed |= !S_ISLNK(st->st_mode) ? TYPE_CHANGED : 0;
+ break;
+ default:
+ die("internal error: ce_mode is %o", ntohl(ce->ce_mode));
+ }
if (ce->ce_mtime.sec != htonl(st->st_mtime))
changed |= MTIME_CHANGED;
if (ce->ce_ctime.sec != htonl(st->st_ctime))
changed |= CTIME_CHANGED;
-#ifdef NSEC
+#ifdef USE_NSEC
/*
* 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)
+ 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)
+ if (ce->ce_ctime.nsec != htonl(st->st_ctim.tv_nsec))
changed |= CTIME_CHANGED;
#endif
if (ce->ce_uid != htonl(st->st_uid) ||
ce->ce_gid != htonl(st->st_gid))
changed |= OWNER_CHANGED;
- /* We consider only the owner x bit to be relevant for "mode changes" */
- if (0100 & (ntohl(ce->ce_mode) ^ st->st_mode))
- changed |= MODE_CHANGED;
- if (ce->ce_dev != htonl(st->st_dev) ||
- ce->ce_ino != htonl(st->st_ino))
+ if (ce->ce_ino != htonl(st->st_ino))
+ changed |= INODE_CHANGED;
+
+#ifdef USE_STDEV
+ /*
+ * st_dev breaks on network filesystems where different
+ * clients will have different views of what "device"
+ * the filesystem is on
+ */
+ if (ce->ce_dev != htonl(st->st_dev))
changed |= INODE_CHANGED;
+#endif
+
if (ce->ce_size != htonl(st->st_size))
changed |= DATA_CHANGED;
return changed;
}
+int base_name_compare(const char *name1, int len1, int mode1,
+ const char *name2, int len2, int mode2)
+{
+ unsigned char c1, c2;
+ int len = len1 < len2 ? len1 : len2;
+ int cmp;
+
+ cmp = memcmp(name1, name2, len);
+ if (cmp)
+ return cmp;
+ c1 = name1[len];
+ c2 = name2[len];
+ if (!c1 && S_ISDIR(mode1))
+ c1 = '/';
+ if (!c2 && S_ISDIR(mode2))
+ c2 = '/';
+ return (c1 < c2) ? -1 : (c1 > c2) ? 1 : 0;
+}
+
int cache_name_compare(const char *name1, int flags1, const char *name2, int flags2)
{
int len1 = flags1 & CE_NAMEMASK;
}
/* Remove entry, return true if there are more entries to go.. */
-static int remove_entry_at(int pos)
+int remove_cache_entry_at(int pos)
{
+ active_cache_changed = 1;
active_nr--;
if (pos >= active_nr)
return 0;
if (pos < 0)
pos = -pos-1;
while (pos < active_nr && !strcmp(active_cache[pos]->name, path))
- remove_entry_at(pos);
+ remove_cache_entry_at(pos);
return 0;
}
-static int same_name(struct cache_entry *a, struct cache_entry *b)
+int ce_same_name(struct cache_entry *a, struct cache_entry *b)
{
int len = ce_namelen(a);
return ce_namelen(b) == len && !memcmp(a->name, b->name, len);
}
-int add_cache_entry(struct cache_entry *ce, int ok_to_add)
+/* We may be in a situation where we already have path/file and path
+ * is being added, or we already have path and path/file is being
+ * added. Either one would result in a nonsense tree that has path
+ * twice when git-write-tree tries to write it out. Prevent it.
+ *
+ * If ok-to-replace is specified, we remove the conflicting entries
+ * from the cache so the caller should recompute the insert position.
+ * When this happens, we return non-zero.
+ */
+static int check_file_directory_conflict(const struct cache_entry *ce,
+ int ok_to_replace)
{
- int pos;
+ int pos, replaced = 0;
+ const char *path = ce->name;
+ int namelen = strlen(path);
+ int stage = ce_stage(ce);
+ char *pathbuf = xmalloc(namelen + 1);
+ char *cp;
+
+ memcpy(pathbuf, path, namelen + 1);
+
+ /*
+ * We are inserting path/file. Do they have path registered at
+ * the same stage? We need to do this for all the levels of our
+ * subpath.
+ */
+ cp = pathbuf;
+ while (1) {
+ char *ep = strchr(cp, '/');
+ if (!ep)
+ break;
+ *ep = 0; /* first cut it at slash */
+ pos = cache_name_pos(pathbuf,
+ htons(create_ce_flags(ep-cp, stage)));
+ if (0 <= pos) {
+ /* Our leading path component is registered as a file,
+ * and we are trying to make it a directory. This is
+ * bad.
+ */
+ if (!ok_to_replace) {
+ free(pathbuf);
+ return -1;
+ }
+ fprintf(stderr, "removing file '%s' to replace it with a directory to create '%s'.\n", pathbuf, path);
+ remove_cache_entry_at(pos);
+ replaced = 1;
+ }
+ *ep = '/'; /* then restore it and go downwards */
+ cp = ep + 1;
+ }
+ free(pathbuf);
+ /* Do we have an entry in the cache that makes our path a prefix
+ * of it? That is, are we creating a file where they already expect
+ * a directory there?
+ */
+ pos = cache_name_pos(path,
+ htons(create_ce_flags(namelen, stage)));
+
+ /* (0 <= pos) cannot happen because add_cache_entry()
+ * should have taken care of that case.
+ */
+ pos = -pos-1;
+
+ /* pos would point at an existing entry that would come immediately
+ * after our path. It could be the same as our path in higher stage,
+ * or different path but in a lower stage.
+ *
+ * E.g. when we are inserting path at stage 2,
+ *
+ * 1 path
+ * pos-> 3 path
+ * 2 path/file1
+ * 3 path/file1
+ * 2 path/file2
+ * 2 patho
+ *
+ * We need to examine pos, ignore it because it is at different
+ * stage, examine next to find the path/file at stage 2, and
+ * complain. We need to do this until we are not the leading
+ * path of an existing entry anymore.
+ */
+
+ while (pos < active_nr) {
+ struct cache_entry *other = active_cache[pos];
+ if (strncmp(other->name, path, namelen))
+ break; /* it is not our "subdirectory" anymore */
+ if ((ce_stage(other) == stage) &&
+ other->name[namelen] == '/') {
+ if (!ok_to_replace)
+ return -1;
+ fprintf(stderr, "removing file '%s' under '%s' to be replaced with a file\n", other->name, path);
+ remove_cache_entry_at(pos);
+ replaced = 1;
+ continue; /* cycle without updating pos */
+ }
+ pos++;
+ }
+ return replaced;
+}
+
+int add_cache_entry(struct cache_entry *ce, int option)
+{
+ int pos;
+ int ok_to_add = option & ADD_CACHE_OK_TO_ADD;
+ int ok_to_replace = option & ADD_CACHE_OK_TO_REPLACE;
pos = cache_name_pos(ce->name, htons(ce->ce_flags));
/* existing match? Just replace it */
if (pos >= 0) {
+ active_cache_changed = 1;
active_cache[pos] = ce;
return 0;
}
* will always replace all non-merged entries..
*/
if (pos < active_nr && ce_stage(ce) == 0) {
- while (same_name(active_cache[pos], ce)) {
+ while (ce_same_name(active_cache[pos], ce)) {
ok_to_add = 1;
- if (!remove_entry_at(pos))
+ if (!remove_cache_entry_at(pos))
break;
}
}
if (!ok_to_add)
return -1;
+ if (check_file_directory_conflict(ce, ok_to_replace)) {
+ if (!ok_to_replace)
+ return -1;
+ pos = cache_name_pos(ce->name, htons(ce->ce_flags));
+ pos = -pos-1;
+ }
+
/* Make sure the array is big enough .. */
if (active_nr == active_alloc) {
active_alloc = alloc_nr(active_alloc);
- active_cache = realloc(active_cache, active_alloc * sizeof(struct cache_entry *));
+ active_cache = xrealloc(active_cache, active_alloc * sizeof(struct cache_entry *));
}
/* Add it in.. */
if (active_nr > pos)
memmove(active_cache + pos + 1, active_cache + pos, (active_nr - pos - 1) * sizeof(ce));
active_cache[pos] = ce;
+ active_cache_changed = 1;
return 0;
}
if (hdr->hdr_signature != htonl(CACHE_SIGNATURE))
return error("bad signature");
- if (hdr->hdr_version != htonl(1))
- return error("bad version");
+ if (hdr->hdr_version != htonl(2))
+ return error("bad index version");
SHA1_Init(&c);
- SHA1_Update(&c, hdr, offsetof(struct cache_header, sha1));
- SHA1_Update(&c, hdr+1, size - sizeof(*hdr));
+ SHA1_Update(&c, hdr, size - 20);
SHA1_Final(sha1, &c);
- if (memcmp(sha1, hdr->sha1, 20))
- return error("bad header sha1");
+ if (memcmp(sha1, (void *)hdr + size - 20, 20))
+ return error("bad index file sha1 signature");
return 0;
}
if (active_cache)
return error("more than one cachefile");
errno = ENOENT;
- sha1_file_directory = getenv(DB_ENVIRONMENT);
- if (!sha1_file_directory)
- sha1_file_directory = DEFAULT_DB_ENVIRONMENT;
- if (access(sha1_file_directory, X_OK) < 0)
- return error("no access to SHA1 file directory");
- fd = open(".git/index", O_RDONLY);
+ fd = open(get_index_file(), O_RDONLY);
if (fd < 0)
return (errno == ENOENT) ? 0 : error("open failed");
if (!fstat(fd, &st)) {
size = st.st_size;
errno = EINVAL;
- if (size >= sizeof(struct cache_header))
- map = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
+ if (size >= sizeof(struct cache_header) + 20)
+ map = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
}
close(fd);
if (-1 == (int)(long)map)
return error("verify header failed");
}
+#define WRITE_BUFFER_SIZE 8192
+static unsigned char write_buffer[WRITE_BUFFER_SIZE];
+static unsigned long write_buffer_len;
+
+static int ce_write(SHA_CTX *context, int fd, void *data, unsigned int len)
+{
+ while (len) {
+ unsigned int buffered = write_buffer_len;
+ unsigned int partial = WRITE_BUFFER_SIZE - buffered;
+ if (partial > len)
+ partial = len;
+ memcpy(write_buffer + buffered, data, partial);
+ buffered += partial;
+ if (buffered == WRITE_BUFFER_SIZE) {
+ SHA1_Update(context, write_buffer, WRITE_BUFFER_SIZE);
+ if (write(fd, write_buffer, WRITE_BUFFER_SIZE) != WRITE_BUFFER_SIZE)
+ return -1;
+ buffered = 0;
+ }
+ write_buffer_len = buffered;
+ len -= partial;
+ data += partial;
+ }
+ return 0;
+}
+
+static int ce_flush(SHA_CTX *context, int fd)
+{
+ unsigned int left = write_buffer_len;
+
+ if (left) {
+ write_buffer_len = 0;
+ SHA1_Update(context, write_buffer, left);
+ }
+
+ /* Append the SHA1 signature at the end */
+ SHA1_Final(write_buffer + left, context);
+ left += 20;
+ if (write(fd, write_buffer, left) != left)
+ return -1;
+ return 0;
+}
+
int write_cache(int newfd, struct cache_entry **cache, int entries)
{
SHA_CTX c;
int i;
hdr.hdr_signature = htonl(CACHE_SIGNATURE);
- hdr.hdr_version = htonl(1);
+ hdr.hdr_version = htonl(2);
hdr.hdr_entries = htonl(entries);
SHA1_Init(&c);
- SHA1_Update(&c, &hdr, offsetof(struct cache_header, sha1));
- for (i = 0; i < entries; i++) {
- struct cache_entry *ce = cache[i];
- int size = ce_size(ce);
- SHA1_Update(&c, ce, size);
- }
- SHA1_Final(hdr.sha1, &c);
-
- if (write(newfd, &hdr, sizeof(hdr)) != sizeof(hdr))
+ if (ce_write(&c, newfd, &hdr, sizeof(hdr)) < 0)
return -1;
for (i = 0; i < entries; i++) {
struct cache_entry *ce = cache[i];
- int size = ce_size(ce);
- if (write(newfd, ce, size) != size)
+ if (ce_write(&c, newfd, ce, ce_size(ce)) < 0)
return -1;
}
- return 0;
+ return ce_flush(&c, newfd);
}