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-rw-r--r--read-cache.c2308
1 files changed, 2308 insertions, 0 deletions
diff --git a/read-cache.c b/read-cache.c
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index 0000000..36ff89f
--- /dev/null
+++ b/read-cache.c
@@ -0,0 +1,2308 @@
+/*
+ * GIT - The information manager from hell
+ *
+ * Copyright (C) Linus Torvalds, 2005
+ */
+#define NO_THE_INDEX_COMPATIBILITY_MACROS
+#include "cache.h"
+#include "lockfile.h"
+#include "cache-tree.h"
+#include "refs.h"
+#include "dir.h"
+#include "tree.h"
+#include "commit.h"
+#include "blob.h"
+#include "resolve-undo.h"
+#include "strbuf.h"
+#include "varint.h"
+#include "split-index.h"
+#include "sigchain.h"
+#include "utf8.h"
+
+static struct cache_entry *refresh_cache_entry(struct cache_entry *ce,
+ unsigned int options);
+
+/* Mask for the name length in ce_flags in the on-disk index */
+
+#define CE_NAMEMASK (0x0fff)
+
+/* Index extensions.
+ *
+ * The first letter should be 'A'..'Z' for extensions that are not
+ * necessary for a correct operation (i.e. optimization data).
+ * When new extensions are added that _needs_ to be understood in
+ * order to correctly interpret the index file, pick character that
+ * is outside the range, to cause the reader to abort.
+ */
+
+#define CACHE_EXT(s) ( (s[0]<<24)|(s[1]<<16)|(s[2]<<8)|(s[3]) )
+#define CACHE_EXT_TREE 0x54524545 /* "TREE" */
+#define CACHE_EXT_RESOLVE_UNDO 0x52455543 /* "REUC" */
+#define CACHE_EXT_LINK 0x6c696e6b /* "link" */
+
+/* changes that can be kept in $GIT_DIR/index (basically all extensions) */
+#define EXTMASK (RESOLVE_UNDO_CHANGED | CACHE_TREE_CHANGED | \
+ CE_ENTRY_ADDED | CE_ENTRY_REMOVED | CE_ENTRY_CHANGED | \
+ SPLIT_INDEX_ORDERED)
+
+struct index_state the_index;
+static const char *alternate_index_output;
+
+static void set_index_entry(struct index_state *istate, int nr, struct cache_entry *ce)
+{
+ istate->cache[nr] = ce;
+ add_name_hash(istate, ce);
+}
+
+static void replace_index_entry(struct index_state *istate, int nr, struct cache_entry *ce)
+{
+ struct cache_entry *old = istate->cache[nr];
+
+ replace_index_entry_in_base(istate, old, ce);
+ remove_name_hash(istate, old);
+ free(old);
+ set_index_entry(istate, nr, ce);
+ ce->ce_flags |= CE_UPDATE_IN_BASE;
+ istate->cache_changed |= CE_ENTRY_CHANGED;
+}
+
+void rename_index_entry_at(struct index_state *istate, int nr, const char *new_name)
+{
+ struct cache_entry *old = istate->cache[nr], *new;
+ int namelen = strlen(new_name);
+
+ new = xmalloc(cache_entry_size(namelen));
+ copy_cache_entry(new, old);
+ new->ce_flags &= ~CE_HASHED;
+ new->ce_namelen = namelen;
+ new->index = 0;
+ memcpy(new->name, new_name, namelen + 1);
+
+ cache_tree_invalidate_path(istate, old->name);
+ remove_index_entry_at(istate, nr);
+ add_index_entry(istate, new, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE);
+}
+
+void fill_stat_data(struct stat_data *sd, struct stat *st)
+{
+ sd->sd_ctime.sec = (unsigned int)st->st_ctime;
+ sd->sd_mtime.sec = (unsigned int)st->st_mtime;
+ sd->sd_ctime.nsec = ST_CTIME_NSEC(*st);
+ sd->sd_mtime.nsec = ST_MTIME_NSEC(*st);
+ sd->sd_dev = st->st_dev;
+ sd->sd_ino = st->st_ino;
+ sd->sd_uid = st->st_uid;
+ sd->sd_gid = st->st_gid;
+ sd->sd_size = st->st_size;
+}
+
+int match_stat_data(const struct stat_data *sd, struct stat *st)
+{
+ int changed = 0;
+
+ if (sd->sd_mtime.sec != (unsigned int)st->st_mtime)
+ changed |= MTIME_CHANGED;
+ if (trust_ctime && check_stat &&
+ sd->sd_ctime.sec != (unsigned int)st->st_ctime)
+ changed |= CTIME_CHANGED;
+
+#ifdef USE_NSEC
+ if (check_stat && sd->sd_mtime.nsec != ST_MTIME_NSEC(*st))
+ changed |= MTIME_CHANGED;
+ if (trust_ctime && check_stat &&
+ sd->sd_ctime.nsec != ST_CTIME_NSEC(*st))
+ changed |= CTIME_CHANGED;
+#endif
+
+ if (check_stat) {
+ if (sd->sd_uid != (unsigned int) st->st_uid ||
+ sd->sd_gid != (unsigned int) st->st_gid)
+ changed |= OWNER_CHANGED;
+ if (sd->sd_ino != (unsigned int) 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 (check_stat && sd->sd_dev != (unsigned int) st->st_dev)
+ changed |= INODE_CHANGED;
+#endif
+
+ if (sd->sd_size != (unsigned int) st->st_size)
+ changed |= DATA_CHANGED;
+
+ return changed;
+}
+
+/*
+ * 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)
+{
+ fill_stat_data(&ce->ce_stat_data, st);
+
+ if (assume_unchanged)
+ ce->ce_flags |= CE_VALID;
+
+ if (S_ISREG(st->st_mode))
+ ce_mark_uptodate(ce);
+}
+
+static int ce_compare_data(const struct cache_entry *ce, struct stat *st)
+{
+ int match = -1;
+ int fd = open(ce->name, O_RDONLY);
+
+ if (fd >= 0) {
+ unsigned char sha1[20];
+ if (!index_fd(sha1, fd, st, OBJ_BLOB, ce->name, 0))
+ match = hashcmp(sha1, ce->sha1);
+ /* index_fd() closed the file descriptor already */
+ }
+ return match;
+}
+
+static int ce_compare_link(const struct cache_entry *ce, size_t expected_size)
+{
+ int match = -1;
+ void *buffer;
+ unsigned long size;
+ enum object_type type;
+ struct strbuf sb = STRBUF_INIT;
+
+ if (strbuf_readlink(&sb, ce->name, expected_size))
+ return -1;
+
+ buffer = read_sha1_file(ce->sha1, &type, &size);
+ if (buffer) {
+ if (size == sb.len)
+ match = memcmp(buffer, sb.buf, size);
+ free(buffer);
+ }
+ strbuf_release(&sb);
+ return match;
+}
+
+static int ce_compare_gitlink(const struct cache_entry *ce)
+{
+ unsigned char sha1[20];
+
+ /*
+ * We don't actually require that the .git directory
+ * under GITLINK directory be a valid git directory. It
+ * might even be missing (in case nobody populated that
+ * sub-project).
+ *
+ * If so, we consider it always to match.
+ */
+ if (resolve_gitlink_ref(ce->name, "HEAD", sha1) < 0)
+ return 0;
+ return hashcmp(sha1, ce->sha1);
+}
+
+static int ce_modified_check_fs(const struct cache_entry *ce, struct stat *st)
+{
+ switch (st->st_mode & S_IFMT) {
+ case S_IFREG:
+ if (ce_compare_data(ce, st))
+ return DATA_CHANGED;
+ break;
+ case S_IFLNK:
+ if (ce_compare_link(ce, xsize_t(st->st_size)))
+ return DATA_CHANGED;
+ break;
+ case S_IFDIR:
+ if (S_ISGITLINK(ce->ce_mode))
+ return ce_compare_gitlink(ce) ? DATA_CHANGED : 0;
+ default:
+ return TYPE_CHANGED;
+ }
+ return 0;
+}
+
+static int ce_match_stat_basic(const struct cache_entry *ce, struct stat *st)
+{
+ unsigned int changed = 0;
+
+ if (ce->ce_flags & CE_REMOVE)
+ return MODE_CHANGED | DATA_CHANGED | TYPE_CHANGED;
+
+ switch (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 (trust_executable_bit &&
+ (0100 & (ce->ce_mode ^ st->st_mode)))
+ changed |= MODE_CHANGED;
+ break;
+ case S_IFLNK:
+ if (!S_ISLNK(st->st_mode) &&
+ (has_symlinks || !S_ISREG(st->st_mode)))
+ changed |= TYPE_CHANGED;
+ break;
+ case S_IFGITLINK:
+ /* We ignore most of the st_xxx fields for gitlinks */
+ if (!S_ISDIR(st->st_mode))
+ changed |= TYPE_CHANGED;
+ else if (ce_compare_gitlink(ce))
+ changed |= DATA_CHANGED;
+ return changed;
+ default:
+ die("internal error: ce_mode is %o", ce->ce_mode);
+ }
+
+ changed |= match_stat_data(&ce->ce_stat_data, st);
+
+ /* Racily smudged entry? */
+ if (!ce->ce_stat_data.sd_size) {
+ if (!is_empty_blob_sha1(ce->sha1))
+ changed |= DATA_CHANGED;
+ }
+
+ return changed;
+}
+
+static int is_racy_timestamp(const struct index_state *istate,
+ const struct cache_entry *ce)
+{
+ return (!S_ISGITLINK(ce->ce_mode) &&
+ istate->timestamp.sec &&
+#ifdef USE_NSEC
+ /* nanosecond timestamped files can also be racy! */
+ (istate->timestamp.sec < ce->ce_stat_data.sd_mtime.sec ||
+ (istate->timestamp.sec == ce->ce_stat_data.sd_mtime.sec &&
+ istate->timestamp.nsec <= ce->ce_stat_data.sd_mtime.nsec))
+#else
+ istate->timestamp.sec <= ce->ce_stat_data.sd_mtime.sec
+#endif
+ );
+}
+
+int ie_match_stat(const struct index_state *istate,
+ const struct cache_entry *ce, struct stat *st,
+ unsigned int options)
+{
+ unsigned int changed;
+ int ignore_valid = options & CE_MATCH_IGNORE_VALID;
+ int ignore_skip_worktree = options & CE_MATCH_IGNORE_SKIP_WORKTREE;
+ int assume_racy_is_modified = options & CE_MATCH_RACY_IS_DIRTY;
+
+ /*
+ * If it's marked as always valid in the index, it's
+ * valid whatever the checked-out copy says.
+ *
+ * skip-worktree has the same effect with higher precedence
+ */
+ if (!ignore_skip_worktree && ce_skip_worktree(ce))
+ return 0;
+ if (!ignore_valid && (ce->ce_flags & CE_VALID))
+ return 0;
+
+ /*
+ * Intent-to-add entries have not been added, so the index entry
+ * by definition never matches what is in the work tree until it
+ * actually gets added.
+ */
+ if (ce->ce_flags & CE_INTENT_TO_ADD)
+ return DATA_CHANGED | TYPE_CHANGED | MODE_CHANGED;
+
+ changed = ce_match_stat_basic(ce, st);
+
+ /*
+ * Within 1 second of this sequence:
+ * echo xyzzy >file && git-update-index --add file
+ * running this command:
+ * echo frotz >file
+ * would give a falsely clean cache entry. The mtime and
+ * length match the cache, and other stat fields do not change.
+ *
+ * We could detect this at update-index time (the cache entry
+ * being registered/updated records the same time as "now")
+ * and delay the return from git-update-index, but that would
+ * effectively mean we can make at most one commit per second,
+ * which is not acceptable. Instead, we check cache entries
+ * whose mtime are the same as the index file timestamp more
+ * carefully than others.
+ */
+ if (!changed && is_racy_timestamp(istate, ce)) {
+ if (assume_racy_is_modified)
+ changed |= DATA_CHANGED;
+ else
+ changed |= ce_modified_check_fs(ce, st);
+ }
+
+ return changed;
+}
+
+int ie_modified(const struct index_state *istate,
+ const struct cache_entry *ce,
+ struct stat *st, unsigned int options)
+{
+ int changed, changed_fs;
+
+ changed = ie_match_stat(istate, ce, st, options);
+ if (!changed)
+ return 0;
+ /*
+ * If the mode or type has changed, there's no point in trying
+ * to refresh the entry - it's not going to match
+ */
+ if (changed & (MODE_CHANGED | TYPE_CHANGED))
+ return changed;
+
+ /*
+ * Immediately after read-tree or update-index --cacheinfo,
+ * the length field is zero, as we have never even read the
+ * lstat(2) information once, and we cannot trust DATA_CHANGED
+ * returned by ie_match_stat() which in turn was returned by
+ * ce_match_stat_basic() to signal that the filesize of the
+ * blob changed. We have to actually go to the filesystem to
+ * see if the contents match, and if so, should answer "unchanged".
+ *
+ * The logic does not apply to gitlinks, as ce_match_stat_basic()
+ * already has checked the actual HEAD from the filesystem in the
+ * subproject. If ie_match_stat() already said it is different,
+ * then we know it is.
+ */
+ if ((changed & DATA_CHANGED) &&
+ (S_ISGITLINK(ce->ce_mode) || ce->ce_stat_data.sd_size != 0))
+ return changed;
+
+ changed_fs = ce_modified_check_fs(ce, st);
+ if (changed_fs)
+ return changed | changed_fs;
+ return 0;
+}
+
+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;
+}
+
+/*
+ * df_name_compare() is identical to base_name_compare(), except it
+ * compares conflicting directory/file entries as equal. Note that
+ * while a directory name compares as equal to a regular file, they
+ * then individually compare _differently_ to a filename that has
+ * a dot after the basename (because '\0' < '.' < '/').
+ *
+ * This is used by routines that want to traverse the git namespace
+ * but then handle conflicting entries together when possible.
+ */
+int df_name_compare(const char *name1, int len1, int mode1,
+ const char *name2, int len2, int mode2)
+{
+ int len = len1 < len2 ? len1 : len2, cmp;
+ unsigned char c1, c2;
+
+ cmp = memcmp(name1, name2, len);
+ if (cmp)
+ return cmp;
+ /* Directories and files compare equal (same length, same name) */
+ if (len1 == len2)
+ return 0;
+ c1 = name1[len];
+ if (!c1 && S_ISDIR(mode1))
+ c1 = '/';
+ c2 = name2[len];
+ if (!c2 && S_ISDIR(mode2))
+ c2 = '/';
+ if (c1 == '/' && !c2)
+ return 0;
+ if (c2 == '/' && !c1)
+ return 0;
+ return c1 - c2;
+}
+
+int name_compare(const char *name1, size_t len1, const char *name2, size_t len2)
+{
+ size_t min_len = (len1 < len2) ? len1 : len2;
+ int cmp = memcmp(name1, name2, min_len);
+ if (cmp)
+ return cmp;
+ if (len1 < len2)
+ return -1;
+ if (len1 > len2)
+ return 1;
+ return 0;
+}
+
+int cache_name_stage_compare(const char *name1, int len1, int stage1, const char *name2, int len2, int stage2)
+{
+ int cmp;
+
+ cmp = name_compare(name1, len1, name2, len2);
+ if (cmp)
+ return cmp;
+
+ if (stage1 < stage2)
+ return -1;
+ if (stage1 > stage2)
+ return 1;
+ return 0;
+}
+
+static int index_name_stage_pos(const struct index_state *istate, const char *name, int namelen, int stage)
+{
+ int first, last;
+
+ first = 0;
+ last = istate->cache_nr;
+ while (last > first) {
+ int next = (last + first) >> 1;
+ struct cache_entry *ce = istate->cache[next];
+ int cmp = cache_name_stage_compare(name, namelen, stage, ce->name, ce_namelen(ce), ce_stage(ce));
+ if (!cmp)
+ return next;
+ if (cmp < 0) {
+ last = next;
+ continue;
+ }
+ first = next+1;
+ }
+ return -first-1;
+}
+
+int index_name_pos(const struct index_state *istate, const char *name, int namelen)
+{
+ return index_name_stage_pos(istate, name, namelen, 0);
+}
+
+/* Remove entry, return true if there are more entries to go.. */
+int remove_index_entry_at(struct index_state *istate, int pos)
+{
+ struct cache_entry *ce = istate->cache[pos];
+
+ record_resolve_undo(istate, ce);
+ remove_name_hash(istate, ce);
+ save_or_free_index_entry(istate, ce);
+ istate->cache_changed |= CE_ENTRY_REMOVED;
+ istate->cache_nr--;
+ if (pos >= istate->cache_nr)
+ return 0;
+ memmove(istate->cache + pos,
+ istate->cache + pos + 1,
+ (istate->cache_nr - pos) * sizeof(struct cache_entry *));
+ return 1;
+}
+
+/*
+ * Remove all cache entries marked for removal, that is where
+ * CE_REMOVE is set in ce_flags. This is much more effective than
+ * calling remove_index_entry_at() for each entry to be removed.
+ */
+void remove_marked_cache_entries(struct index_state *istate)
+{
+ struct cache_entry **ce_array = istate->cache;
+ unsigned int i, j;
+
+ for (i = j = 0; i < istate->cache_nr; i++) {
+ if (ce_array[i]->ce_flags & CE_REMOVE) {
+ remove_name_hash(istate, ce_array[i]);
+ save_or_free_index_entry(istate, ce_array[i]);
+ }
+ else
+ ce_array[j++] = ce_array[i];
+ }
+ if (j == istate->cache_nr)
+ return;
+ istate->cache_changed |= CE_ENTRY_REMOVED;
+ istate->cache_nr = j;
+}
+
+int remove_file_from_index(struct index_state *istate, const char *path)
+{
+ int pos = index_name_pos(istate, path, strlen(path));
+ if (pos < 0)
+ pos = -pos-1;
+ cache_tree_invalidate_path(istate, path);
+ while (pos < istate->cache_nr && !strcmp(istate->cache[pos]->name, path))
+ remove_index_entry_at(istate, pos);
+ return 0;
+}
+
+static int compare_name(struct cache_entry *ce, const char *path, int namelen)
+{
+ return namelen != ce_namelen(ce) || memcmp(path, ce->name, namelen);
+}
+
+static int index_name_pos_also_unmerged(struct index_state *istate,
+ const char *path, int namelen)
+{
+ int pos = index_name_pos(istate, path, namelen);
+ struct cache_entry *ce;
+
+ if (pos >= 0)
+ return pos;
+
+ /* maybe unmerged? */
+ pos = -1 - pos;
+ if (pos >= istate->cache_nr ||
+ compare_name((ce = istate->cache[pos]), path, namelen))
+ return -1;
+
+ /* order of preference: stage 2, 1, 3 */
+ if (ce_stage(ce) == 1 && pos + 1 < istate->cache_nr &&
+ ce_stage((ce = istate->cache[pos + 1])) == 2 &&
+ !compare_name(ce, path, namelen))
+ pos++;
+ return pos;
+}
+
+static int different_name(struct cache_entry *ce, struct cache_entry *alias)
+{
+ int len = ce_namelen(ce);
+ return ce_namelen(alias) != len || memcmp(ce->name, alias->name, len);
+}
+
+/*
+ * If we add a filename that aliases in the cache, we will use the
+ * name that we already have - but we don't want to update the same
+ * alias twice, because that implies that there were actually two
+ * different files with aliasing names!
+ *
+ * So we use the CE_ADDED flag to verify that the alias was an old
+ * one before we accept it as
+ */
+static struct cache_entry *create_alias_ce(struct index_state *istate,
+ struct cache_entry *ce,
+ struct cache_entry *alias)
+{
+ int len;
+ struct cache_entry *new;
+
+ if (alias->ce_flags & CE_ADDED)
+ die("Will not add file alias '%s' ('%s' already exists in index)", ce->name, alias->name);
+
+ /* Ok, create the new entry using the name of the existing alias */
+ len = ce_namelen(alias);
+ new = xcalloc(1, cache_entry_size(len));
+ memcpy(new->name, alias->name, len);
+ copy_cache_entry(new, ce);
+ save_or_free_index_entry(istate, ce);
+ return new;
+}
+
+void set_object_name_for_intent_to_add_entry(struct cache_entry *ce)
+{
+ unsigned char sha1[20];
+ if (write_sha1_file("", 0, blob_type, sha1))
+ die("cannot create an empty blob in the object database");
+ hashcpy(ce->sha1, sha1);
+}
+
+int add_to_index(struct index_state *istate, const char *path, struct stat *st, int flags)
+{
+ int size, namelen, was_same;
+ mode_t st_mode = st->st_mode;
+ struct cache_entry *ce, *alias;
+ unsigned ce_option = CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE|CE_MATCH_RACY_IS_DIRTY;
+ int verbose = flags & (ADD_CACHE_VERBOSE | ADD_CACHE_PRETEND);
+ int pretend = flags & ADD_CACHE_PRETEND;
+ int intent_only = flags & ADD_CACHE_INTENT;
+ int add_option = (ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE|
+ (intent_only ? ADD_CACHE_NEW_ONLY : 0));
+
+ if (!S_ISREG(st_mode) && !S_ISLNK(st_mode) && !S_ISDIR(st_mode))
+ return error("%s: can only add regular files, symbolic links or git-directories", path);
+
+ namelen = strlen(path);
+ if (S_ISDIR(st_mode)) {
+ while (namelen && path[namelen-1] == '/')
+ namelen--;
+ }
+ size = cache_entry_size(namelen);
+ ce = xcalloc(1, size);
+ memcpy(ce->name, path, namelen);
+ ce->ce_namelen = namelen;
+ if (!intent_only)
+ fill_stat_cache_info(ce, st);
+ else
+ ce->ce_flags |= CE_INTENT_TO_ADD;
+
+ if (trust_executable_bit && has_symlinks)
+ ce->ce_mode = create_ce_mode(st_mode);
+ else {
+ /* If there is an existing entry, pick the mode bits and type
+ * from it, otherwise assume unexecutable regular file.
+ */
+ struct cache_entry *ent;
+ int pos = index_name_pos_also_unmerged(istate, path, namelen);
+
+ ent = (0 <= pos) ? istate->cache[pos] : NULL;
+ ce->ce_mode = ce_mode_from_stat(ent, st_mode);
+ }
+
+ /* When core.ignorecase=true, determine if a directory of the same name but differing
+ * case already exists within the Git repository. If it does, ensure the directory
+ * case of the file being added to the repository matches (is folded into) the existing
+ * entry's directory case.
+ */
+ if (ignore_case) {
+ const char *startPtr = ce->name;
+ const char *ptr = startPtr;
+ while (*ptr) {
+ while (*ptr && *ptr != '/')
+ ++ptr;
+ if (*ptr == '/') {
+ struct cache_entry *foundce;
+ ++ptr;
+ foundce = index_dir_exists(istate, ce->name, ptr - ce->name - 1);
+ if (foundce) {
+ memcpy((void *)startPtr, foundce->name + (startPtr - ce->name), ptr - startPtr);
+ startPtr = ptr;
+ }
+ }
+ }
+ }
+
+ alias = index_file_exists(istate, ce->name, ce_namelen(ce), ignore_case);
+ if (alias && !ce_stage(alias) && !ie_match_stat(istate, alias, st, ce_option)) {
+ /* Nothing changed, really */
+ if (!S_ISGITLINK(alias->ce_mode))
+ ce_mark_uptodate(alias);
+ alias->ce_flags |= CE_ADDED;
+
+ free(ce);
+ return 0;
+ }
+ if (!intent_only) {
+ if (index_path(ce->sha1, path, st, HASH_WRITE_OBJECT)) {
+ free(ce);
+ return error("unable to index file %s", path);
+ }
+ } else
+ set_object_name_for_intent_to_add_entry(ce);
+
+ if (ignore_case && alias && different_name(ce, alias))
+ ce = create_alias_ce(istate, ce, alias);
+ ce->ce_flags |= CE_ADDED;
+
+ /* It was suspected to be racily clean, but it turns out to be Ok */
+ was_same = (alias &&
+ !ce_stage(alias) &&
+ !hashcmp(alias->sha1, ce->sha1) &&
+ ce->ce_mode == alias->ce_mode);
+
+ if (pretend)
+ free(ce);
+ else if (add_index_entry(istate, ce, add_option)) {
+ free(ce);
+ return error("unable to add %s to index", path);
+ }
+ if (verbose && !was_same)
+ printf("add '%s'\n", path);
+ return 0;
+}
+
+int add_file_to_index(struct index_state *istate, const char *path, int flags)
+{
+ struct stat st;
+ if (lstat(path, &st))
+ die_errno("unable to stat '%s'", path);
+ return add_to_index(istate, path, &st, flags);
+}
+
+struct cache_entry *make_cache_entry(unsigned int mode,
+ const unsigned char *sha1, const char *path, int stage,
+ unsigned int refresh_options)
+{
+ int size, len;
+ struct cache_entry *ce, *ret;
+
+ if (!verify_path(path)) {
+ error("Invalid path '%s'", path);
+ return NULL;
+ }
+
+ len = strlen(path);
+ size = cache_entry_size(len);
+ ce = xcalloc(1, size);
+
+ hashcpy(ce->sha1, sha1);
+ memcpy(ce->name, path, len);
+ ce->ce_flags = create_ce_flags(stage);
+ ce->ce_namelen = len;
+ ce->ce_mode = create_ce_mode(mode);
+
+ ret = refresh_cache_entry(ce, refresh_options);
+ if (ret != ce)
+ free(ce);
+ return ret;
+}
+
+int ce_same_name(const struct cache_entry *a, const struct cache_entry *b)
+{
+ int len = ce_namelen(a);
+ return ce_namelen(b) == len && !memcmp(a->name, b->name, len);
+}
+
+/*
+ * We fundamentally don't like some paths: we don't want
+ * dot or dot-dot anywhere, and for obvious reasons don't
+ * want to recurse into ".git" either.
+ *
+ * Also, we don't want double slashes or slashes at the
+ * end that can make pathnames ambiguous.
+ */
+static int verify_dotfile(const char *rest)
+{
+ /*
+ * The first character was '.', but that
+ * has already been discarded, we now test
+ * the rest.
+ */
+
+ /* "." is not allowed */
+ 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.
+ */
+ case 'g':
+ case 'G':
+ if (rest[1] != 'i' && rest[1] != 'I')
+ break;
+ if (rest[2] != 't' && rest[2] != 'T')
+ break;
+ rest += 2;
+ /* fallthrough */
+ case '.':
+ if (rest[1] == '\0' || is_dir_sep(rest[1]))
+ return 0;
+ }
+ return 1;
+}
+
+int verify_path(const char *path)
+{
+ char c;
+
+ if (has_dos_drive_prefix(path))
+ return 0;
+
+ goto inside;
+ for (;;) {
+ if (!c)
+ return 1;
+ if (is_dir_sep(c)) {
+inside:
+ if (protect_hfs && is_hfs_dotgit(path))
+ return 0;
+ if (protect_ntfs && is_ntfs_dotgit(path))
+ return 0;
+ c = *path++;
+ if ((c == '.' && !verify_dotfile(path)) ||
+ is_dir_sep(c) || c == '\0')
+ return 0;
+ }
+ c = *path++;
+ }
+}
+
+/*
+ * Do we have another file that has the beginning components being a
+ * proper superset of the name we're trying to add?
+ */
+static int has_file_name(struct index_state *istate,
+ const struct cache_entry *ce, int pos, int ok_to_replace)
+{
+ int retval = 0;
+ int len = ce_namelen(ce);
+ int stage = ce_stage(ce);
+ const char *name = ce->name;
+
+ while (pos < istate->cache_nr) {
+ struct cache_entry *p = istate->cache[pos++];
+
+ if (len >= ce_namelen(p))
+ break;
+ if (memcmp(name, p->name, len))
+ break;
+ if (ce_stage(p) != stage)
+ continue;
+ if (p->name[len] != '/')
+ continue;
+ if (p->ce_flags & CE_REMOVE)
+ continue;
+ retval = -1;
+ if (!ok_to_replace)
+ break;
+ remove_index_entry_at(istate, --pos);
+ }
+ return retval;
+}
+
+/*
+ * Do we have another file with a pathname that is a proper
+ * subset of the name we're trying to add?
+ */
+static int has_dir_name(struct index_state *istate,
+ const struct cache_entry *ce, int pos, int ok_to_replace)
+{
+ int retval = 0;
+ int stage = ce_stage(ce);
+ const char *name = ce->name;
+ const char *slash = name + ce_namelen(ce);
+
+ for (;;) {
+ int len;
+
+ for (;;) {
+ if (*--slash == '/')
+ break;
+ if (slash <= ce->name)
+ return retval;
+ }
+ len = slash - name;
+
+ pos = index_name_stage_pos(istate, name, len, stage);
+ if (pos >= 0) {
+ /*
+ * Found one, but not so fast. This could
+ * be a marker that says "I was here, but
+ * I am being removed". Such an entry is
+ * not a part of the resulting tree, and
+ * it is Ok to have a directory at the same
+ * path.
+ */
+ if (!(istate->cache[pos]->ce_flags & CE_REMOVE)) {
+ retval = -1;
+ if (!ok_to_replace)
+ break;
+ remove_index_entry_at(istate, pos);
+ continue;
+ }
+ }
+ else
+ pos = -pos-1;
+
+ /*
+ * Trivial optimization: if we find an entry that
+ * already matches the sub-directory, then we know
+ * we're ok, and we can exit.
+ */
+ while (pos < istate->cache_nr) {
+ struct cache_entry *p = istate->cache[pos];
+ if ((ce_namelen(p) <= len) ||
+ (p->name[len] != '/') ||
+ memcmp(p->name, name, len))
+ break; /* not our subdirectory */
+ if (ce_stage(p) == stage && !(p->ce_flags & CE_REMOVE))
+ /*
+ * p is at the same stage as our entry, and
+ * is a subdirectory of what we are looking
+ * at, so we cannot have conflicts at our
+ * level or anything shorter.
+ */
+ return retval;
+ pos++;
+ }
+ }
+ return retval;
+}
+
+/* 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(struct index_state *istate,
+ const struct cache_entry *ce,
+ int pos, int ok_to_replace)
+{
+ int retval;
+
+ /*
+ * When ce is an "I am going away" entry, we allow it to be added
+ */
+ if (ce->ce_flags & CE_REMOVE)
+ return 0;
+
+ /*
+ * We check if the path is a sub-path of a subsequent pathname
+ * first, since removing those will not change the position
+ * in the array.
+ */
+ retval = has_file_name(istate, ce, pos, ok_to_replace);
+
+ /*
+ * Then check if the path might have a clashing sub-directory
+ * before it.
+ */
+ return retval + has_dir_name(istate, ce, pos, ok_to_replace);
+}
+
+static int add_index_entry_with_check(struct index_state *istate, 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;
+ int skip_df_check = option & ADD_CACHE_SKIP_DFCHECK;
+ int new_only = option & ADD_CACHE_NEW_ONLY;
+
+ if (!(option & ADD_CACHE_KEEP_CACHE_TREE))
+ cache_tree_invalidate_path(istate, ce->name);
+ pos = index_name_stage_pos(istate, ce->name, ce_namelen(ce), ce_stage(ce));
+
+ /* existing match? Just replace it. */
+ if (pos >= 0) {
+ if (!new_only)
+ replace_index_entry(istate, 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 < istate->cache_nr && ce_stage(ce) == 0) {
+ while (ce_same_name(istate->cache[pos], ce)) {
+ ok_to_add = 1;
+ if (!remove_index_entry_at(istate, pos))
+ break;
+ }
+ }
+
+ if (!ok_to_add)
+ return -1;
+ if (!verify_path(ce->name))
+ return error("Invalid path '%s'", ce->name);
+
+ if (!skip_df_check &&
+ check_file_directory_conflict(istate, ce, pos, ok_to_replace)) {
+ if (!ok_to_replace)
+ return error("'%s' appears as both a file and as a directory",
+ ce->name);
+ pos = index_name_stage_pos(istate, ce->name, ce_namelen(ce), ce_stage(ce));
+ pos = -pos-1;
+ }
+ return pos + 1;
+}
+
+int add_index_entry(struct index_state *istate, struct cache_entry *ce, int option)
+{
+ int pos;
+
+ if (option & ADD_CACHE_JUST_APPEND)
+ pos = istate->cache_nr;
+ else {
+ int ret;
+ ret = add_index_entry_with_check(istate, ce, option);
+ if (ret <= 0)
+ return ret;
+ pos = ret - 1;
+ }
+
+ /* Make sure the array is big enough .. */
+ ALLOC_GROW(istate->cache, istate->cache_nr + 1, istate->cache_alloc);
+
+ /* Add it in.. */
+ istate->cache_nr++;
+ if (istate->cache_nr > pos + 1)
+ memmove(istate->cache + pos + 1,
+ istate->cache + pos,
+ (istate->cache_nr - pos - 1) * sizeof(ce));
+ set_index_entry(istate, pos, ce);
+ istate->cache_changed |= CE_ENTRY_ADDED;
+ return 0;
+}
+
+/*
+ * "refresh" does not calculate a new sha1 file or bring the
+ * cache up-to-date for mode/content changes. But what it
+ * _does_ do is to "re-match" the stat information of a file
+ * with the cache, so that you can refresh the cache for a
+ * file that hasn't been changed but where the stat entry is
+ * out of date.
+ *
+ * For example, you'd want to do this after doing a "git-read-tree",
+ * to link up the stat cache details with the proper files.
+ */
+static struct cache_entry *refresh_cache_ent(struct index_state *istate,
+ struct cache_entry *ce,
+ unsigned int options, int *err,
+ int *changed_ret)
+{
+ struct stat st;
+ struct cache_entry *updated;
+ int changed, size;
+ int refresh = options & CE_MATCH_REFRESH;
+ int ignore_valid = options & CE_MATCH_IGNORE_VALID;
+ int ignore_skip_worktree = options & CE_MATCH_IGNORE_SKIP_WORKTREE;
+ int ignore_missing = options & CE_MATCH_IGNORE_MISSING;
+
+ if (!refresh || ce_uptodate(ce))
+ return ce;
+
+ /*
+ * CE_VALID or CE_SKIP_WORKTREE means the user promised us
+ * that the change to the work tree does not matter and told
+ * us not to worry.
+ */
+ if (!ignore_skip_worktree && ce_skip_worktree(ce)) {
+ ce_mark_uptodate(ce);
+ return ce;
+ }
+ if (!ignore_valid && (ce->ce_flags & CE_VALID)) {
+ ce_mark_uptodate(ce);
+ return ce;
+ }
+
+ if (has_symlink_leading_path(ce->name, ce_namelen(ce))) {
+ if (ignore_missing)
+ return ce;
+ if (err)
+ *err = ENOENT;
+ return NULL;
+ }
+
+ if (lstat(ce->name, &st) < 0) {
+ if (ignore_missing && errno == ENOENT)
+ return ce;
+ if (err)
+ *err = errno;
+ return NULL;
+ }
+
+ 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
+ * valid bit, then we did the actual stat check and
+ * found that the entry is unmodified. If the entry
+ * is not marked VALID, this is the place to mark it
+ * valid again, under "assume unchanged" mode.
+ */
+ if (ignore_valid && assume_unchanged &&
+ !(ce->ce_flags & CE_VALID))
+ ; /* mark this one VALID again */
+ else {
+ /*
+ * We do not mark the index itself "modified"
+ * because CE_UPTODATE flag is in-core only;
+ * we are not going to write this change out.
+ */
+ if (!S_ISGITLINK(ce->ce_mode))
+ ce_mark_uptodate(ce);
+ return ce;
+ }
+ }
+
+ if (ie_modified(istate, ce, &st, options)) {
+ if (err)
+ *err = EINVAL;
+ return NULL;
+ }
+
+ size = ce_size(ce);
+ updated = xmalloc(size);
+ memcpy(updated, ce, size);
+ fill_stat_cache_info(updated, &st);
+ /*
+ * If ignore_valid is not set, we should leave CE_VALID bit
+ * alone. Otherwise, paths marked with --no-assume-unchanged
+ * (i.e. things to be edited) will reacquire CE_VALID bit
+ * automatically, which is not really what we want.
+ */
+ if (!ignore_valid && assume_unchanged &&
+ !(ce->ce_flags & CE_VALID))
+ updated->ce_flags &= ~CE_VALID;
+
+ /* istate->cache_changed is updated in the caller */
+ return updated;
+}
+
+static void show_file(const char * fmt, const char * name, int in_porcelain,
+ int * first, const char *header_msg)
+{
+ if (in_porcelain && *first && header_msg) {
+ printf("%s\n", header_msg);
+ *first = 0;
+ }
+ printf(fmt, name);
+}
+
+int refresh_index(struct index_state *istate, unsigned int flags,
+ const struct pathspec *pathspec,
+ char *seen, const char *header_msg)
+{
+ int i;
+ int has_errors = 0;
+ int really = (flags & REFRESH_REALLY) != 0;
+ int allow_unmerged = (flags & REFRESH_UNMERGED) != 0;
+ int quiet = (flags & REFRESH_QUIET) != 0;
+ int not_new = (flags & REFRESH_IGNORE_MISSING) != 0;
+ int ignore_submodules = (flags & REFRESH_IGNORE_SUBMODULES) != 0;
+ int first = 1;
+ int in_porcelain = (flags & REFRESH_IN_PORCELAIN);
+ unsigned int options = (CE_MATCH_REFRESH |
+ (really ? CE_MATCH_IGNORE_VALID : 0) |
+ (not_new ? CE_MATCH_IGNORE_MISSING : 0));
+ 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 && !ce_path_match(ce, pathspec, seen))
+ filtered = 1;
+
+ if (ce_stage(ce)) {
+ while ((i < istate->cache_nr) &&
+ ! strcmp(istate->cache[i]->name, ce->name))
+ i++;
+ i--;
+ if (allow_unmerged)
+ continue;
+ if (!filtered)
+ show_file(unmerged_fmt, ce->name, in_porcelain,
+ &first, header_msg);
+ has_errors = 1;
+ continue;
+ }
+
+ if (filtered)
+ continue;
+
+ new = refresh_cache_ent(istate, ce, options, &cache_errno, &changed);
+ if (new == ce)
+ continue;
+ if (!new) {
+ const char *fmt;
+
+ if (really && cache_errno == EINVAL) {
+ /* If we are doing --really-refresh that
+ * means the index is not valid anymore.
+ */
+ ce->ce_flags &= ~CE_VALID;
+ ce->ce_flags |= CE_UPDATE_IN_BASE;
+ istate->cache_changed |= CE_ENTRY_CHANGED;
+ }
+ if (quiet)
+ continue;
+
+ 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;
+ }
+
+ replace_index_entry(istate, i, new);
+ }
+ return has_errors;
+}
+
+static struct cache_entry *refresh_cache_entry(struct cache_entry *ce,
+ unsigned int options)
+{
+ return refresh_cache_ent(&the_index, ce, options, NULL, NULL);
+}
+
+
+/*****************************************************************
+ * Index File I/O
+ *****************************************************************/
+
+#define INDEX_FORMAT_DEFAULT 3
+
+static unsigned int get_index_format_default(void)
+{
+ char *envversion = getenv("GIT_INDEX_VERSION");
+ char *endp;
+ int value;
+ unsigned int version = INDEX_FORMAT_DEFAULT;
+
+ if (!envversion) {
+ if (!git_config_get_int("index.version", &value))
+ version = value;
+ if (version < INDEX_FORMAT_LB || INDEX_FORMAT_UB < version) {
+ warning(_("index.version set, but the value is invalid.\n"
+ "Using version %i"), INDEX_FORMAT_DEFAULT);
+ return INDEX_FORMAT_DEFAULT;
+ }
+ return version;
+ }
+
+ version = strtoul(envversion, &endp, 10);
+ if (*endp ||
+ version < INDEX_FORMAT_LB || INDEX_FORMAT_UB < version) {
+ warning(_("GIT_INDEX_VERSION set, but the value is invalid.\n"
+ "Using version %i"), INDEX_FORMAT_DEFAULT);
+ version = INDEX_FORMAT_DEFAULT;
+ }
+ return version;
+}
+
+/*
+ * 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;
+ uint32_t dev;
+ uint32_t ino;
+ uint32_t mode;
+ uint32_t uid;
+ uint32_t gid;
+ uint32_t size;
+ unsigned char sha1[20];
+ uint16_t 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;
+ uint32_t dev;
+ uint32_t ino;
+ uint32_t mode;
+ uint32_t uid;
+ uint32_t gid;
+ uint32_t size;
+ unsigned char sha1[20];
+ uint16_t flags;
+ uint16_t 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");
+ hdr_version = ntohl(hdr->hdr_version);
+ if (hdr_version < INDEX_FORMAT_LB || INDEX_FORMAT_UB < 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);
+ if (hashcmp(sha1, (unsigned char *)hdr + size - 20))
+ return error("bad index file sha1 signature");
+ return 0;
+}
+
+static int read_index_extension(struct index_state *istate,
+ const char *ext, void *data, unsigned long sz)
+{
+ switch (CACHE_EXT(ext)) {
+ case CACHE_EXT_TREE:
+ istate->cache_tree = cache_tree_read(data, sz);
+ break;
+ case CACHE_EXT_RESOLVE_UNDO:
+ istate->resolve_undo = resolve_undo_read(data, sz);
+ break;
+ case CACHE_EXT_LINK:
+ if (read_link_extension(istate, data, sz))
+ return -1;
+ break;
+ default:
+ if (*ext < 'A' || 'Z' < *ext)
+ return error("index uses %.4s extension, which we do not understand",
+ ext);
+ fprintf(stderr, "ignoring %.4s extension\n", ext);
+ break;
+ }
+ return 0;
+}
+
+int hold_locked_index(struct lock_file *lk, int die_on_error)
+{
+ return hold_lock_file_for_update(lk, get_index_file(),
+ die_on_error
+ ? LOCK_DIE_ON_ERROR
+ : 0);
+}
+
+int read_index(struct index_state *istate)
+{
+ return read_index_from(istate, get_index_file());
+}
+
+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_stat_data.sd_ctime.sec = get_be32(&ondisk->ctime.sec);
+ ce->ce_stat_data.sd_mtime.sec = get_be32(&ondisk->mtime.sec);
+ ce->ce_stat_data.sd_ctime.nsec = get_be32(&ondisk->ctime.nsec);
+ ce->ce_stat_data.sd_mtime.nsec = get_be32(&ondisk->mtime.nsec);
+ ce->ce_stat_data.sd_dev = get_be32(&ondisk->dev);
+ ce->ce_stat_data.sd_ino = get_be32(&ondisk->ino);
+ ce->ce_mode = get_be32(&ondisk->mode);
+ ce->ce_stat_data.sd_uid = get_be32(&ondisk->uid);
+ ce->ce_stat_data.sd_gid = get_be32(&ondisk->gid);
+ ce->ce_stat_data.sd_size = get_be32(&ondisk->size);
+ ce->ce_flags = flags & ~CE_NAMEMASK;
+ ce->ce_namelen = len;
+ ce->index = 0;
+ 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;
+
+ /* On-disk flags are just 16 bits */
+ flags = get_be16(&ondisk->flags);
+ len = flags & CE_NAMEMASK;
+
+ if (flags & CE_EXTENDED) {
+ struct ondisk_cache_entry_extended *ondisk2;
+ int extended_flags;
+ ondisk2 = (struct ondisk_cache_entry_extended *)ondisk;
+ extended_flags = get_be16(&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);
+ flags |= extended_flags;
+ name = ondisk2->name;
+ }
+ else
+ name = ondisk->name;
+
+ 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;
+}
+
+static void check_ce_order(struct index_state *istate)
+{
+ unsigned int i;
+
+ for (i = 1; i < istate->cache_nr; i++) {
+ struct cache_entry *ce = istate->cache[i - 1];
+ struct cache_entry *next_ce = istate->cache[i];
+ int name_compare = strcmp(ce->name, next_ce->name);
+
+ if (0 < name_compare)
+ die("unordered stage entries in index");
+ if (!name_compare) {
+ if (!ce_stage(ce))
+ die("multiple stage entries for merged file '%s'",
+ ce->name);
+ if (ce_stage(ce) > ce_stage(next_ce))
+ die("unordered stage entries for '%s'",
+ ce->name);
+ }
+ }
+}
+
+/* remember to discard_cache() before reading a different cache! */
+int do_read_index(struct index_state *istate, const char *path, int must_exist)
+{
+ int fd, i;
+ struct stat st;
+ unsigned long src_offset;
+ struct cache_header *hdr;
+ void *mmap;
+ size_t mmap_size;
+ struct strbuf previous_name_buf = STRBUF_INIT, *previous_name;
+
+ if (istate->initialized)
+ return istate->cache_nr;
+
+ istate->timestamp.sec = 0;
+ istate->timestamp.nsec = 0;
+ fd = open(path, O_RDONLY);
+ if (fd < 0) {
+ if (!must_exist && errno == ENOENT)
+ return 0;
+ die_errno("%s: index file open failed", path);
+ }
+
+ if (fstat(fd, &st))
+ die_errno("cannot stat the open index");
+
+ mmap_size = xsize_t(st.st_size);
+ if (mmap_size < sizeof(struct cache_header) + 20)
+ die("index file smaller than expected");
+
+ mmap = xmmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
+ if (mmap == MAP_FAILED)
+ die_errno("unable to map index file");
+ close(fd);
+
+ hdr = mmap;
+ if (verify_hdr(hdr, mmap_size) < 0)
+ goto unmap;
+
+ hashcpy(istate->sha1, (const unsigned char *)hdr + mmap_size - 20);
+ 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(*istate->cache));
+ istate->initialized = 1;
+
+ if (istate->version == 4)
+ previous_name = &previous_name_buf;
+ else
+ previous_name = NULL;
+
+ src_offset = sizeof(*hdr);
+ 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 = create_from_disk(disk_ce, &consumed, previous_name);
+ set_index_entry(istate, i, ce);
+
+ src_offset += consumed;
+ }
+ strbuf_release(&previous_name_buf);
+ istate->timestamp.sec = st.st_mtime;
+ istate->timestamp.nsec = ST_MTIME_NSEC(st);
+
+ while (src_offset <= mmap_size - 20 - 8) {
+ /* After an array of active_nr index entries,
+ * there can be arbitrary number of extended
+ * sections, each of which is prefixed with
+ * extension name (4-byte) and section length
+ * in 4-byte network byte order.
+ */
+ uint32_t extsize;
+ memcpy(&extsize, (char *)mmap + src_offset + 4, 4);
+ extsize = ntohl(extsize);
+ if (read_index_extension(istate,
+ (const char *) mmap + src_offset,
+ (char *) mmap + src_offset + 8,
+ extsize) < 0)
+ goto unmap;
+ src_offset += 8;
+ src_offset += extsize;
+ }
+ munmap(mmap, mmap_size);
+ return istate->cache_nr;
+
+unmap:
+ munmap(mmap, mmap_size);
+ die("index file corrupt");
+}
+
+int read_index_from(struct index_state *istate, const char *path)
+{
+ struct split_index *split_index;
+ int ret;
+
+ /* istate->initialized covers both .git/index and .git/sharedindex.xxx */
+ if (istate->initialized)
+ return istate->cache_nr;
+
+ ret = do_read_index(istate, path, 0);
+ split_index = istate->split_index;
+ if (!split_index || is_null_sha1(split_index->base_sha1)) {
+ check_ce_order(istate);
+ return ret;
+ }
+
+ if (split_index->base)
+ discard_index(split_index->base);
+ else
+ split_index->base = xcalloc(1, sizeof(*split_index->base));
+ ret = do_read_index(split_index->base,
+ git_path("sharedindex.%s",
+ sha1_to_hex(split_index->base_sha1)), 1);
+ if (hashcmp(split_index->base_sha1, split_index->base->sha1))
+ die("broken index, expect %s in %s, got %s",
+ sha1_to_hex(split_index->base_sha1),
+ git_path("sharedindex.%s",
+ sha1_to_hex(split_index->base_sha1)),
+ sha1_to_hex(split_index->base->sha1));
+ merge_base_index(istate);
+ check_ce_order(istate);
+ return ret;
+}
+
+int is_index_unborn(struct index_state *istate)
+{
+ return (!istate->cache_nr && !istate->timestamp.sec);
+}
+
+int discard_index(struct index_state *istate)
+{
+ int i;
+
+ for (i = 0; i < istate->cache_nr; i++) {
+ if (istate->cache[i]->index &&
+ istate->split_index &&
+ istate->split_index->base &&
+ istate->cache[i]->index <= istate->split_index->base->cache_nr &&
+ istate->cache[i] == istate->split_index->base->cache[istate->cache[i]->index - 1])
+ continue;
+ free(istate->cache[i]);
+ }
+ resolve_undo_clear_index(istate);
+ istate->cache_nr = 0;
+ istate->cache_changed = 0;
+ istate->timestamp.sec = 0;
+ istate->timestamp.nsec = 0;
+ free_name_hash(istate);
+ cache_tree_free(&(istate->cache_tree));
+ istate->initialized = 0;
+ free(istate->cache);
+ istate->cache = NULL;
+ istate->cache_alloc = 0;
+ discard_split_index(istate);
+ return 0;
+}
+
+int unmerged_index(const struct index_state *istate)
+{
+ int i;
+ for (i = 0; i < istate->cache_nr; i++) {
+ if (ce_stage(istate->cache[i]))
+ return 1;
+ }
+ return 0;
+}
+
+#define WRITE_BUFFER_SIZE 8192
+static unsigned char write_buffer[WRITE_BUFFER_SIZE];
+static unsigned long write_buffer_len;
+
+static int ce_write_flush(git_SHA_CTX *context, int fd)
+{
+ unsigned int buffered = write_buffer_len;
+ if (buffered) {
+ git_SHA1_Update(context, write_buffer, buffered);
+ if (write_in_full(fd, write_buffer, buffered) != buffered)
+ return -1;
+ write_buffer_len = 0;
+ }
+ return 0;
+}
+
+static int ce_write(git_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) {
+ write_buffer_len = buffered;
+ if (ce_write_flush(context, fd))
+ return -1;
+ buffered = 0;
+ }
+ write_buffer_len = buffered;
+ len -= partial;
+ data = (char *) data + partial;
+ }
+ return 0;
+}
+
+static int write_index_ext_header(git_SHA_CTX *context, int fd,
+ unsigned int ext, unsigned int sz)
+{
+ ext = htonl(ext);
+ sz = htonl(sz);
+ return ((ce_write(context, fd, &ext, 4) < 0) ||
+ (ce_write(context, fd, &sz, 4) < 0)) ? -1 : 0;
+}
+
+static int ce_flush(git_SHA_CTX *context, int fd, unsigned char *sha1)
+{
+ unsigned int left = write_buffer_len;
+
+ if (left) {
+ write_buffer_len = 0;
+ git_SHA1_Update(context, write_buffer, left);
+ }
+
+ /* Flush first if not enough space for SHA1 signature */
+ if (left + 20 > WRITE_BUFFER_SIZE) {
+ if (write_in_full(fd, write_buffer, left) != left)
+ return -1;
+ left = 0;
+ }
+
+ /* Append the SHA1 signature at the end */
+ git_SHA1_Final(write_buffer + left, context);
+ hashcpy(sha1, write_buffer + left);
+ left += 20;
+ return (write_in_full(fd, write_buffer, left) != left) ? -1 : 0;
+}
+
+static void ce_smudge_racily_clean_entry(struct cache_entry *ce)
+{
+ /*
+ * The only thing we care about in this function is to smudge the
+ * falsely clean entry due to touch-update-touch race, so we leave
+ * everything else as they are. We are called for entries whose
+ * ce_stat_data.sd_mtime match the index file mtime.
+ *
+ * Note that this actually does not do much for gitlinks, for
+ * which ce_match_stat_basic() always goes to the actual
+ * contents. The caller checks with is_racy_timestamp() which
+ * always says "no" for gitlinks, so we are not called for them ;-)
+ */
+ struct stat st;
+
+ if (lstat(ce->name, &st) < 0)
+ return;
+ if (ce_match_stat_basic(ce, &st))
+ return;
+ if (ce_modified_check_fs(ce, &st)) {
+ /* This is "racily clean"; smudge it. Note that this
+ * is a tricky code. At first glance, it may appear
+ * that it can break with this sequence:
+ *
+ * $ echo xyzzy >frotz
+ * $ git-update-index --add frotz
+ * $ : >frotz
+ * $ sleep 3
+ * $ echo filfre >nitfol
+ * $ git-update-index --add nitfol
+ *
+ * but it does not. When the second update-index runs,
+ * it notices that the entry "frotz" has the same timestamp
+ * as index, and if we were to smudge it by resetting its
+ * size to zero here, then the object name recorded
+ * in index is the 6-byte file but the cached stat information
+ * becomes zero --- which would then match what we would
+ * obtain from the filesystem next time we stat("frotz").
+ *
+ * However, the second update-index, before calling
+ * this function, notices that the cached size is 6
+ * bytes and what is on the filesystem is an empty
+ * file, and never calls us, so the cached size information
+ * for "frotz" stays 6 which does not match the filesystem.
+ */
+ ce->ce_stat_data.sd_size = 0;
+ }
+}
+
+/* Copy miscellaneous fields but not the name */
+static char *copy_cache_entry_to_ondisk(struct ondisk_cache_entry *ondisk,
+ struct cache_entry *ce)
+{
+ short flags;
+
+ ondisk->ctime.sec = htonl(ce->ce_stat_data.sd_ctime.sec);
+ ondisk->mtime.sec = htonl(ce->ce_stat_data.sd_mtime.sec);
+ ondisk->ctime.nsec = htonl(ce->ce_stat_data.sd_ctime.nsec);
+ ondisk->mtime.nsec = htonl(ce->ce_stat_data.sd_mtime.nsec);
+ ondisk->dev = htonl(ce->ce_stat_data.sd_dev);
+ ondisk->ino = htonl(ce->ce_stat_data.sd_ino);
+ ondisk->mode = htonl(ce->ce_mode);
+ ondisk->uid = htonl(ce->ce_stat_data.sd_uid);
+ ondisk->gid = htonl(ce->ce_stat_data.sd_gid);
+ ondisk->size = htonl(ce->ce_stat_data.sd_size);
+ hashcpy(ondisk->sha1, ce->sha1);
+
+ flags = ce->ce_flags & ~CE_NAMEMASK;
+ flags |= (ce_namelen(ce) >= CE_NAMEMASK ? CE_NAMEMASK : ce_namelen(ce));
+ ondisk->flags = htons(flags);
+ if (ce->ce_flags & CE_EXTENDED) {
+ struct ondisk_cache_entry_extended *ondisk2;
+ ondisk2 = (struct ondisk_cache_entry_extended *)ondisk;
+ ondisk2->flags2 = htons((ce->ce_flags & CE_EXTENDED_FLAGS) >> 16);
+ 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;
+ int saved_namelen = saved_namelen; /* compiler workaround */
+ char *name;
+ int result;
+
+ if (ce->ce_flags & CE_STRIP_NAME) {
+ saved_namelen = ce_namelen(ce);
+ ce->ce_namelen = 0;
+ }
+
+ 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);
+ }
+ if (ce->ce_flags & CE_STRIP_NAME) {
+ ce->ce_namelen = saved_namelen;
+ ce->ce_flags &= ~CE_STRIP_NAME;
+ }
+
+ result = ce_write(c, fd, ondisk, size);
+ free(ondisk);
+ return result;
+}
+
+/*
+ * This function verifies if index_state has the correct sha1 of the
+ * index file. Don't die if we have any other failure, just return 0.
+ */
+static int verify_index_from(const struct index_state *istate, const char *path)
+{
+ int fd;
+ ssize_t n;
+ struct stat st;
+ unsigned char sha1[20];
+
+ if (!istate->initialized)
+ return 0;
+
+ fd = open(path, O_RDONLY);
+ if (fd < 0)
+ return 0;
+
+ if (fstat(fd, &st))
+ goto out;
+
+ if (st.st_size < sizeof(struct cache_header) + 20)
+ goto out;
+
+ n = pread_in_full(fd, sha1, 20, st.st_size - 20);
+ if (n != 20)
+ goto out;
+
+ if (hashcmp(istate->sha1, sha1))
+ goto out;
+
+ close(fd);
+ return 1;
+
+out:
+ close(fd);
+ return 0;
+}
+
+static int verify_index(const struct index_state *istate)
+{
+ return verify_index_from(istate, get_index_file());
+}
+
+static int has_racy_timestamp(struct index_state *istate)
+{
+ int entries = istate->cache_nr;
+ int i;
+
+ for (i = 0; i < entries; i++) {
+ struct cache_entry *ce = istate->cache[i];
+ if (is_racy_timestamp(istate, ce))
+ return 1;
+ }
+ return 0;
+}
+
+/*
+ * Opportunistically update the index but do not complain if we can't
+ */
+void update_index_if_able(struct index_state *istate, struct lock_file *lockfile)
+{
+ if ((istate->cache_changed || has_racy_timestamp(istate)) &&
+ verify_index(istate) &&
+ write_locked_index(istate, lockfile, COMMIT_LOCK))
+ rollback_lock_file(lockfile);
+}
+
+static int do_write_index(struct index_state *istate, int newfd,
+ int strip_extensions)
+{
+ git_SHA_CTX c;
+ struct cache_header hdr;
+ 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)
+ removed++;
+
+ /* reduce extended entries if possible */
+ cache[i]->ce_flags &= ~CE_EXTENDED;
+ if (cache[i]->ce_flags & CE_EXTENDED_FLAGS) {
+ extended++;
+ cache[i]->ce_flags |= CE_EXTENDED;
+ }
+ }
+
+ if (!istate->version) {
+ istate->version = get_index_format_default();
+ if (getenv("GIT_TEST_SPLIT_INDEX"))
+ init_split_index(istate);
+ }
+
+ /* 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);
+ 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 (is_null_sha1(ce->sha1)) {
+ static const char msg[] = "cache entry has null sha1: %s";
+ static int allow = -1;
+
+ if (allow < 0)
+ allow = git_env_bool("GIT_ALLOW_NULL_SHA1", 0);
+ if (allow)
+ warning(msg, ce->name);
+ else
+ return error(msg, ce->name);
+ }
+ if (ce_write_entry(&c, newfd, ce, previous_name) < 0)
+ return -1;
+ }
+ strbuf_release(&previous_name_buf);
+
+ /* Write extension data here */
+ if (!strip_extensions && istate->split_index) {
+ struct strbuf sb = STRBUF_INIT;
+
+ err = write_link_extension(&sb, istate) < 0 ||
+ write_index_ext_header(&c, newfd, CACHE_EXT_LINK,
+ sb.len) < 0 ||
+ ce_write(&c, newfd, sb.buf, sb.len) < 0;
+ strbuf_release(&sb);
+ if (err)
+ return -1;
+ }
+ if (!strip_extensions && istate->cache_tree) {
+ struct strbuf sb = STRBUF_INIT;
+
+ cache_tree_write(&sb, istate->cache_tree);
+ err = write_index_ext_header(&c, newfd, CACHE_EXT_TREE, sb.len) < 0
+ || ce_write(&c, newfd, sb.buf, sb.len) < 0;
+ strbuf_release(&sb);
+ if (err)
+ return -1;
+ }
+ if (!strip_extensions && istate->resolve_undo) {
+ struct strbuf sb = STRBUF_INIT;
+
+ resolve_undo_write(&sb, istate->resolve_undo);
+ err = write_index_ext_header(&c, newfd, CACHE_EXT_RESOLVE_UNDO,
+ sb.len) < 0
+ || ce_write(&c, newfd, sb.buf, sb.len) < 0;
+ strbuf_release(&sb);
+ if (err)
+ return -1;
+ }
+
+ if (ce_flush(&c, newfd, istate->sha1) || fstat(newfd, &st))
+ return -1;
+ istate->timestamp.sec = (unsigned int)st.st_mtime;
+ istate->timestamp.nsec = ST_MTIME_NSEC(st);
+ return 0;
+}
+
+void set_alternate_index_output(const char *name)
+{
+ alternate_index_output = name;
+}
+
+static int commit_locked_index(struct lock_file *lk)
+{
+ if (alternate_index_output)
+ return commit_lock_file_to(lk, alternate_index_output);
+ else
+ return commit_lock_file(lk);
+}
+
+static int do_write_locked_index(struct index_state *istate, struct lock_file *lock,
+ unsigned flags)
+{
+ int ret = do_write_index(istate, lock->fd, 0);
+ if (ret)
+ return ret;
+ assert((flags & (COMMIT_LOCK | CLOSE_LOCK)) !=
+ (COMMIT_LOCK | CLOSE_LOCK));
+ if (flags & COMMIT_LOCK)
+ return commit_locked_index(lock);
+ else if (flags & CLOSE_LOCK)
+ return close_lock_file(lock);
+ else
+ return ret;
+}
+
+static int write_split_index(struct index_state *istate,
+ struct lock_file *lock,
+ unsigned flags)
+{
+ int ret;
+ prepare_to_write_split_index(istate);
+ ret = do_write_locked_index(istate, lock, flags);
+ finish_writing_split_index(istate);
+ return ret;
+}
+
+static char *temporary_sharedindex;
+
+static void remove_temporary_sharedindex(void)
+{
+ if (temporary_sharedindex) {
+ unlink_or_warn(temporary_sharedindex);
+ free(temporary_sharedindex);
+ temporary_sharedindex = NULL;
+ }
+}
+
+static void remove_temporary_sharedindex_on_signal(int signo)
+{
+ remove_temporary_sharedindex();
+ sigchain_pop(signo);
+ raise(signo);
+}
+
+static int write_shared_index(struct index_state *istate,
+ struct lock_file *lock, unsigned flags)
+{
+ struct split_index *si = istate->split_index;
+ static int installed_handler;
+ int fd, ret;
+
+ temporary_sharedindex = git_pathdup("sharedindex_XXXXXX");
+ fd = mkstemp(temporary_sharedindex);
+ if (fd < 0) {
+ free(temporary_sharedindex);
+ temporary_sharedindex = NULL;
+ hashclr(si->base_sha1);
+ return do_write_locked_index(istate, lock, flags);
+ }
+ if (!installed_handler) {
+ atexit(remove_temporary_sharedindex);
+ sigchain_push_common(remove_temporary_sharedindex_on_signal);
+ }
+ move_cache_to_base_index(istate);
+ ret = do_write_index(si->base, fd, 1);
+ close(fd);
+ if (ret) {
+ remove_temporary_sharedindex();
+ return ret;
+ }
+ ret = rename(temporary_sharedindex,
+ git_path("sharedindex.%s", sha1_to_hex(si->base->sha1)));
+ free(temporary_sharedindex);
+ temporary_sharedindex = NULL;
+ if (!ret)
+ hashcpy(si->base_sha1, si->base->sha1);
+ return ret;
+}
+
+int write_locked_index(struct index_state *istate, struct lock_file *lock,
+ unsigned flags)
+{
+ struct split_index *si = istate->split_index;
+
+ if (!si || alternate_index_output ||
+ (istate->cache_changed & ~EXTMASK)) {
+ if (si)
+ hashclr(si->base_sha1);
+ return do_write_locked_index(istate, lock, flags);
+ }
+
+ if (getenv("GIT_TEST_SPLIT_INDEX")) {
+ int v = si->base_sha1[0];
+ if ((v & 15) < 6)
+ istate->cache_changed |= SPLIT_INDEX_ORDERED;
+ }
+ if (istate->cache_changed & SPLIT_INDEX_ORDERED) {
+ int ret = write_shared_index(istate, lock, flags);
+ if (ret)
+ return ret;
+ }
+
+ return write_split_index(istate, lock, flags);
+}
+
+/*
+ * Read the index file that is potentially unmerged into given
+ * index_state, dropping any unmerged entries. Returns true if
+ * the index is unmerged. Callers who want to refuse to work
+ * from an unmerged state can call this and check its return value,
+ * instead of calling read_cache().
+ */
+int read_index_unmerged(struct index_state *istate)
+{
+ int i;
+ int unmerged = 0;
+
+ read_index(istate);
+ for (i = 0; i < istate->cache_nr; i++) {
+ struct cache_entry *ce = istate->cache[i];
+ struct cache_entry *new_ce;
+ int size, len;
+
+ if (!ce_stage(ce))
+ continue;
+ unmerged = 1;
+ len = ce_namelen(ce);
+ size = cache_entry_size(len);
+ new_ce = xcalloc(1, size);
+ memcpy(new_ce->name, ce->name, len);
+ new_ce->ce_flags = create_ce_flags(0) | CE_CONFLICTED;
+ new_ce->ce_namelen = len;
+ new_ce->ce_mode = ce->ce_mode;
+ if (add_index_entry(istate, new_ce, 0))
+ return error("%s: cannot drop to stage #0",
+ new_ce->name);
+ }
+ return unmerged;
+}
+
+/*
+ * Returns 1 if the path is an "other" path with respect to
+ * the index; that is, the path is not mentioned in the index at all,
+ * either as a file, a directory with some files in the index,
+ * or as an unmerged entry.
+ *
+ * We helpfully remove a trailing "/" from directories so that
+ * the output of read_directory can be used as-is.
+ */
+int index_name_is_other(const struct index_state *istate, const char *name,
+ int namelen)
+{
+ int pos;
+ if (namelen && name[namelen - 1] == '/')
+ namelen--;
+ pos = index_name_pos(istate, name, namelen);
+ if (0 <= pos)
+ return 0; /* exact match */
+ pos = -pos - 1;
+ if (pos < istate->cache_nr) {
+ struct cache_entry *ce = istate->cache[pos];
+ if (ce_namelen(ce) == namelen &&
+ !memcmp(ce->name, name, namelen))
+ return 0; /* Yup, this one exists unmerged */
+ }
+ return 1;
+}
+
+void *read_blob_data_from_index(struct index_state *istate, const char *path, unsigned long *size)
+{
+ int pos, len;
+ unsigned long sz;
+ enum object_type type;
+ void *data;
+
+ len = strlen(path);
+ pos = index_name_pos(istate, path, len);
+ if (pos < 0) {
+ /*
+ * We might be in the middle of a merge, in which
+ * case we would read stage #2 (ours).
+ */
+ int i;
+ for (i = -pos - 1;
+ (pos < 0 && i < istate->cache_nr &&
+ !strcmp(istate->cache[i]->name, path));
+ i++)
+ if (ce_stage(istate->cache[i]) == 2)
+ pos = i;
+ }
+ if (pos < 0)
+ return NULL;
+ data = read_sha1_file(istate->cache[pos]->sha1, &type, &sz);
+ if (!data || type != OBJ_BLOB) {
+ free(data);
+ return NULL;
+ }
+ if (size)
+ *size = sz;
+ return data;
+}
+
+void stat_validity_clear(struct stat_validity *sv)
+{
+ free(sv->sd);
+ sv->sd = NULL;
+}
+
+int stat_validity_check(struct stat_validity *sv, const char *path)
+{
+ struct stat st;
+
+ if (stat(path, &st) < 0)
+ return sv->sd == NULL;
+ if (!sv->sd)
+ return 0;
+ return S_ISREG(st.st_mode) && !match_stat_data(sv->sd, &st);
+}
+
+void stat_validity_update(struct stat_validity *sv, int fd)
+{
+ struct stat st;
+
+ if (fstat(fd, &st) < 0 || !S_ISREG(st.st_mode))
+ stat_validity_clear(sv);
+ else {
+ if (!sv->sd)
+ sv->sd = xcalloc(1, sizeof(struct stat_data));
+ fill_stat_data(sv->sd, &st);
+ }
+}