*/
#include "cache.h"
-const char *sha1_file_directory = NULL;
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;
-void usage(const char *err)
+/*
+ * 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)
{
- fprintf(stderr, "read-tree: %s\n", err);
- exit(1);
+ 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);
}
-static unsigned hexval(char c)
+int ce_match_stat(struct cache_entry *ce, struct stat *st)
{
- if (c >= '0' && c <= '9')
- return c - '0';
- if (c >= 'a' && c <= 'f')
- return c - 'a' + 10;
- if (c >= 'A' && c <= 'F')
- return c - 'A' + 10;
- return ~0;
+ 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 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))
+ changed |= MTIME_CHANGED;
+ 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;
+ 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 get_sha1_hex(char *hex, unsigned char *sha1)
+int base_name_compare(const char *name1, int len1, int mode1,
+ const char *name2, int len2, int mode2)
{
- int i;
- for (i = 0; i < 20; i++) {
- unsigned int val = (hexval(hex[0]) << 4) | hexval(hex[1]);
- if (val & ~0xff)
- return -1;
- *sha1++ = val;
- hex += 2;
- }
- return 0;
+ 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;
}
-char * sha1_to_hex(unsigned char *sha1)
+int cache_name_compare(const char *name1, int flags1, const char *name2, int flags2)
{
- static char buffer[50];
- static const char hex[] = "0123456789abcdef";
- char *buf = buffer;
- int i;
-
- for (i = 0; i < 20; i++) {
- unsigned int val = *sha1++;
- *buf++ = hex[val >> 4];
- *buf++ = hex[val & 0xf];
- }
- return buffer;
+ int len1 = flags1 & CE_NAMEMASK;
+ int len2 = flags2 & CE_NAMEMASK;
+ int len = len1 < len2 ? len1 : len2;
+ int cmp;
+
+ cmp = memcmp(name1, name2, len);
+ if (cmp)
+ return cmp;
+ if (len1 < len2)
+ return -1;
+ if (len1 > len2)
+ return 1;
+ if (flags1 < flags2)
+ return -1;
+ if (flags1 > flags2)
+ return 1;
+ return 0;
}
-/*
- * NOTE! This returns a statically allocated buffer, so you have to be
- * careful about using it. Do a "strdup()" if you need to save the
- * filename.
- */
-char *sha1_file_name(unsigned char *sha1)
+int cache_name_pos(const char *name, int namelen)
{
- int i;
- static char *name, *base;
-
- if (!base) {
- char *sha1_file_directory = getenv(DB_ENVIRONMENT) ? : DEFAULT_DB_ENVIRONMENT;
- int len = strlen(sha1_file_directory);
- base = malloc(len + 60);
- memcpy(base, sha1_file_directory, len);
- memset(base+len, 0, 60);
- base[len] = '/';
- base[len+3] = '/';
- name = base + len + 1;
- }
- for (i = 0; i < 20; i++) {
- static char hex[] = "0123456789abcdef";
- unsigned int val = sha1[i];
- char *pos = name + i*2 + (i > 0);
- *pos++ = hex[val >> 4];
- *pos = hex[val & 0xf];
+ int first, last;
+
+ first = 0;
+ last = active_nr;
+ while (last > first) {
+ int next = (last + first) >> 1;
+ struct cache_entry *ce = active_cache[next];
+ int cmp = cache_name_compare(name, namelen, ce->name, htons(ce->ce_flags));
+ if (!cmp)
+ return next;
+ if (cmp < 0) {
+ last = next;
+ continue;
+ }
+ first = next+1;
}
- return base;
+ return -first-1;
}
-int check_sha1_signature(unsigned char *sha1, void *map, unsigned long size)
+/* Remove entry, return true if there are more entries to go.. */
+int remove_cache_entry_at(int pos)
{
- unsigned char real_sha1[20];
- SHA_CTX c;
-
- SHA1_Init(&c);
- SHA1_Update(&c, map, size);
- SHA1_Final(real_sha1, &c);
- return memcmp(sha1, real_sha1, 20) ? -1 : 0;
+ active_cache_changed = 1;
+ active_nr--;
+ if (pos >= active_nr)
+ return 0;
+ memmove(active_cache + pos, active_cache + pos + 1, (active_nr - pos) * sizeof(struct cache_entry *));
+ return 1;
}
-void *map_sha1_file(unsigned char *sha1, unsigned long *size)
+int remove_file_from_cache(char *path)
{
- char *filename = sha1_file_name(sha1);
- int fd = open(filename, O_RDONLY);
- struct stat st;
- void *map;
-
- if (fd < 0) {
- perror(filename);
- return NULL;
- }
- if (fstat(fd, &st) < 0) {
- close(fd);
- return NULL;
- }
- map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
- close(fd);
- if (-1 == (int)(long)map)
- return NULL;
- *size = st.st_size;
- return map;
+ int pos = cache_name_pos(path, strlen(path));
+ if (pos < 0)
+ pos = -pos-1;
+ while (pos < active_nr && !strcmp(active_cache[pos]->name, path))
+ remove_cache_entry_at(pos);
+ return 0;
}
-void * unpack_sha1_file(void *map, unsigned long mapsize, char *type, unsigned long *size)
+int ce_same_name(struct cache_entry *a, struct cache_entry *b)
{
- int ret, bytes;
- z_stream stream;
- char buffer[8192];
- char *buf;
-
- /* Get the data stream */
- memset(&stream, 0, sizeof(stream));
- stream.next_in = map;
- stream.avail_in = mapsize;
- stream.next_out = buffer;
- stream.avail_out = sizeof(buffer);
-
- inflateInit(&stream);
- ret = inflate(&stream, 0);
- if (sscanf(buffer, "%10s %lu", type, size) != 2)
- return NULL;
-
- bytes = strlen(buffer) + 1;
- buf = malloc(*size);
- if (!buf)
- return NULL;
-
- memcpy(buf, buffer + bytes, stream.total_out - bytes);
- bytes = stream.total_out - bytes;
- if (bytes < *size && ret == Z_OK) {
- stream.next_out = buf + bytes;
- stream.avail_out = *size - bytes;
- while (inflate(&stream, Z_FINISH) == Z_OK)
- /* nothing */;
- }
- inflateEnd(&stream);
- return buf;
+ int len = ce_namelen(a);
+ return ce_namelen(b) == len && !memcmp(a->name, b->name, len);
}
-void * read_sha1_file(unsigned char *sha1, char *type, unsigned long *size)
+/* 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)
{
- unsigned long mapsize;
- void *map, *buf;
-
- map = map_sha1_file(sha1, &mapsize);
- if (map) {
- buf = unpack_sha1_file(map, mapsize, type, size);
- munmap(map, mapsize);
- return buf;
+ 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, '/');
+ int len;
+ if (!ep)
+ break;
+ *ep = 0; /* first cut it at slash */
+ len = ep - pathbuf;
+ pos = cache_name_pos(pathbuf,
+ htons(create_ce_flags(len, 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 NULL;
+ return replaced;
}
-int write_sha1_file(char *buf, unsigned len)
+int add_cache_entry(struct cache_entry *ce, int option)
{
- int size;
- char *compressed;
- z_stream stream;
- unsigned char sha1[20];
- SHA_CTX c;
-
- /* Set it up */
- memset(&stream, 0, sizeof(stream));
- deflateInit(&stream, Z_BEST_COMPRESSION);
- size = deflateBound(&stream, len);
- compressed = malloc(size);
-
- /* Compress it */
- stream.next_in = buf;
- stream.avail_in = len;
- stream.next_out = compressed;
- stream.avail_out = size;
- while (deflate(&stream, Z_FINISH) == Z_OK)
- /* nothing */;
- deflateEnd(&stream);
- size = stream.total_out;
-
- /* Sha1.. */
- SHA1_Init(&c);
- SHA1_Update(&c, compressed, size);
- SHA1_Final(sha1, &c);
+ 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;
+ }
+ pos = -pos-1;
+
+ /*
+ * Inserting a merged entry ("stage 0") into the index
+ * will always replace all non-merged entries..
+ */
+ if (pos < active_nr && ce_stage(ce) == 0) {
+ while (ce_same_name(active_cache[pos], ce)) {
+ ok_to_add = 1;
+ if (!remove_cache_entry_at(pos))
+ break;
+ }
+ }
- if (write_sha1_buffer(sha1, compressed, size) < 0)
+ if (!ok_to_add)
return -1;
- printf("%s\n", sha1_to_hex(sha1));
- return 0;
-}
-int write_sha1_buffer(unsigned char *sha1, void *buf, unsigned int size)
-{
- char *filename = sha1_file_name(sha1);
- int fd;
+ 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;
+ }
- fd = open(filename, O_WRONLY | O_CREAT | O_EXCL, 0666);
- if (fd < 0)
- return (errno == EEXIST) ? 0 : -1;
- write(fd, buf, size);
- close(fd);
- return 0;
-}
+ /* Make sure the array is big enough .. */
+ if (active_nr == active_alloc) {
+ active_alloc = alloc_nr(active_alloc);
+ active_cache = xrealloc(active_cache, active_alloc * sizeof(struct cache_entry *));
+ }
-static int error(const char * string)
-{
- fprintf(stderr, "error: %s\n", string);
- return -1;
+ /* Add it in.. */
+ active_nr++;
+ 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;
}
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)
- 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(".dircache/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)
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;
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;
+ struct cache_header hdr;
+ int i;
+
+ hdr.hdr_signature = htonl(CACHE_SIGNATURE);
+ hdr.hdr_version = htonl(2);
+ hdr.hdr_entries = htonl(entries);
+
+ SHA1_Init(&c);
+ if (ce_write(&c, newfd, &hdr, sizeof(hdr)) < 0)
+ return -1;
+
+ for (i = 0; i < entries; i++) {
+ struct cache_entry *ce = cache[i];
+ if (ce_write(&c, newfd, ce, ce_size(ce)) < 0)
+ return -1;
+ }
+ return ce_flush(&c, newfd);
+}