Move name hashing functions into a file of its own

[thirdparty/git.git] / read-cache.c

diff --git a/read-cache.c b/read-cache.c
index 657f0c5894c65831b80ceee54d161d0beac1d733..5dc998d21e79a8950896e7bb0db38cb137faacc1 100644 (file)
--- a/read-cache.c
+++ b/read-cache.c
@@ -23,80 +23,21 @@
 
 struct index_state the_index;
 
-static unsigned int hash_name(const char *name, int namelen)
-{
-       unsigned int hash = 0x123;
-
-       do {
-               unsigned char c = *name++;
-               hash = hash*101 + c;
-       } while (--namelen);
-       return hash;
-}
-
-static void hash_index_entry(struct index_state *istate, struct cache_entry *ce)
-{
-       void **pos;
-       unsigned int hash;
-
-       if (ce->ce_flags & CE_HASHED)
-               return;
-       ce->ce_flags |= CE_HASHED;
-       ce->next = NULL;
-       hash = hash_name(ce->name, ce_namelen(ce));
-       pos = insert_hash(hash, ce, &istate->name_hash);
-       if (pos) {
-               ce->next = *pos;
-               *pos = ce;
-       }
-}
-
-static void lazy_init_name_hash(struct index_state *istate)
-{
-       int nr;
-
-       if (istate->name_hash_initialized)
-               return;
-       for (nr = 0; nr < istate->cache_nr; nr++)
-               hash_index_entry(istate, istate->cache[nr]);
-       istate->name_hash_initialized = 1;
-}
-
 static void set_index_entry(struct index_state *istate, int nr, struct cache_entry *ce)
 {
-       ce->ce_flags &= ~CE_UNHASHED;
        istate->cache[nr] = ce;
-       if (istate->name_hash_initialized)
-               hash_index_entry(istate, 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];
 
-       remove_index_entry(old);
+       remove_name_hash(old);
        set_index_entry(istate, nr, ce);
        istate->cache_changed = 1;
 }
 
-int index_name_exists(struct index_state *istate, const char *name, int namelen)
-{
-       unsigned int hash = hash_name(name, namelen);
-       struct cache_entry *ce;
-
-       lazy_init_name_hash(istate);
-       ce = lookup_hash(hash, &istate->name_hash);
-
-       while (ce) {
-               if (!(ce->ce_flags & CE_UNHASHED)) {
-                       if (!cache_name_compare(name, namelen, ce->name, ce->ce_flags))
-                               return 1;
-               }
-               ce = ce->next;
-       }
-       return 0;
-}
-
 /*
  * This only updates the "non-critical" parts of the directory
  * cache, ie the parts that aren't tracked by GIT, and only used
@@ -255,13 +196,13 @@ static int ce_match_stat_basic(struct cache_entry *ce, struct stat *st)
        return changed;
 }
 
-static int is_racy_timestamp(struct index_state *istate, struct cache_entry *ce)
+static int is_racy_timestamp(const struct index_state *istate, struct cache_entry *ce)
 {
        return (istate->timestamp &&
                ((unsigned int)istate->timestamp) <= ce->ce_mtime);
 }
 
-int ie_match_stat(struct index_state *istate,
+int ie_match_stat(const struct index_state *istate,
                  struct cache_entry *ce, struct stat *st,
                  unsigned int options)
 {
@@ -304,7 +245,7 @@ int ie_match_stat(struct index_state *istate,
        return changed;
 }
 
-int ie_modified(struct index_state *istate,
+int ie_modified(const struct index_state *istate,
                struct cache_entry *ce, struct stat *st, unsigned int options)
 {
        int changed, changed_fs;
@@ -351,6 +292,41 @@ int base_name_compare(const char *name1, int len1, int mode1,
        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 cache_name_compare(const char *name1, int flags1, const char *name2, int flags2)
 {
        int len1 = flags1 & CE_NAMEMASK;
@@ -377,7 +353,7 @@ int cache_name_compare(const char *name1, int flags1, const char *name2, int fla
        return 0;
 }
 
-int index_name_pos(struct index_state *istate, const char *name, int namelen)
+int index_name_pos(const struct index_state *istate, const char *name, int namelen)
 {
        int first, last;
 
@@ -403,7 +379,7 @@ int remove_index_entry_at(struct index_state *istate, int pos)
 {
        struct cache_entry *ce = istate->cache[pos];
 
-       remove_index_entry(ce);
+       remove_name_hash(ce);
        istate->cache_changed = 1;
        istate->cache_nr--;
        if (pos >= istate->cache_nr)
@@ -1166,7 +1142,7 @@ int discard_index(struct index_state *istate)
        return 0;
 }
 
-int unmerged_index(struct index_state *istate)
+int unmerged_index(const struct index_state *istate)
 {
        int i;
        for (i = 0; i < istate->cache_nr; i++) {
@@ -1311,7 +1287,7 @@ static int ce_write_entry(SHA_CTX *c, int fd, struct cache_entry *ce)
        return ce_write(c, fd, ondisk, size);
 }
 
-int write_index(struct index_state *istate, int newfd)
+int write_index(const struct index_state *istate, int newfd)
 {
        SHA_CTX c;
        struct cache_header hdr;