get_sha1() shorthands for blob/tree objects

[git.git] / sha1_name.c

diff --git a/sha1_name.c b/sha1_name.c
index 74c479c..0cd1139 100644 (file)
--- a/sha1_name.c
+++ b/sha1_name.c
@@ -3,6 +3,7 @@
 #include "commit.h"
 #include "tree.h"
 #include "blob.h"
+#include "diff.h"
 
 static int find_short_object_filename(int len, const char *name, unsigned char *sha1)
 {
@@ -235,18 +236,21 @@ static int ambiguous_path(const char *path, int len)
 
 static int get_sha1_basic(const char *str, int len, unsigned char *sha1)
 {
-       static const char *prefix[] = {
-               "",
-               "refs",
-               "refs/tags",
-               "refs/heads",
-               "refs/remotes",
+       static const char *fmt[] = {
+               "%.*s",
+               "refs/%.*s",
+               "refs/tags/%.*s",
+               "refs/heads/%.*s",
+               "refs/remotes/%.*s",
+               "refs/remotes/%.*s/HEAD",
                NULL
        };
        const char **p;
        const char *warning = "warning: refname '%.*s' is ambiguous.\n";
        char *pathname;
        int already_found = 0;
+       unsigned char *this_result;
+       unsigned char sha1_from_ref[20];
 
        if (len == 40 && !get_sha1_hex(str, sha1))
                return 0;
@@ -255,15 +259,12 @@ static int get_sha1_basic(const char *str, int len, unsigned char *sha1)
        if (ambiguous_path(str, len))
                return -1;
 
-       for (p = prefix; *p; p++) {
-               unsigned char sha1_from_ref[20];
-               unsigned char *this_result =
-                       already_found ? sha1_from_ref : sha1;
-               pathname = git_path("%s/%.*s", *p, len, str);
+       for (p = fmt; *p; p++) {
+               this_result = already_found ? sha1_from_ref : sha1;
+               pathname = git_path(*p, len, str);
                if (!read_ref(pathname, this_result)) {
                        if (warn_ambiguous_refs) {
-                               if (already_found &&
-                                   !memcmp(sha1, sha1_from_ref, 20))
+                               if (already_found)
                                        fprintf(stderr, warning, len, str);
                                already_found++;
                        }
@@ -449,12 +450,76 @@ static int get_sha1_1(const char *name, int len, unsigned char *sha1)
        return get_short_sha1(name, len, sha1, 0);
 }
 
+static int get_tree_entry(const unsigned char *, const char *, unsigned char *);
+
+static int find_tree_entry(struct tree_desc *t, const char *name, unsigned char *result)
+{
+       int namelen = strlen(name);
+       while (t->size) {
+               const char *entry;
+               const unsigned char *sha1;
+               int entrylen, cmp;
+               unsigned mode;
+
+               sha1 = tree_entry_extract(t, &entry, &mode);
+               update_tree_entry(t);
+               entrylen = strlen(entry);
+               if (entrylen > namelen)
+                       continue;
+               cmp = memcmp(name, entry, entrylen);
+               if (cmp > 0)
+                       continue;
+               if (cmp < 0)
+                       break;
+               if (entrylen == namelen) {
+                       memcpy(result, sha1, 20);
+                       return 0;
+               }
+               if (name[entrylen] != '/')
+                       continue;
+               if (!S_ISDIR(mode))
+                       break;
+               if (++entrylen == namelen) {
+                       memcpy(result, sha1, 20);
+                       return 0;
+               }
+               return get_tree_entry(sha1, name + entrylen, result);
+       }
+       return -1;
+}
+
+static int get_tree_entry(const unsigned char *tree_sha1, const char *name, unsigned char *sha1)
+{
+       int retval;
+       void *tree;
+       struct tree_desc t;
+
+       tree = read_object_with_reference(tree_sha1, tree_type, &t.size, NULL);
+       if (!tree)
+               return -1;
+       t.buf = tree;
+       retval = find_tree_entry(&t, name, sha1);
+       free(tree);
+       return retval;
+}
+
 /*
  * This is like "get_sha1_basic()", except it allows "sha1 expressions",
  * notably "xyz^" for "parent of xyz"
  */
 int get_sha1(const char *name, unsigned char *sha1)
 {
+       int ret;
+
        prepare_alt_odb();
-       return get_sha1_1(name, strlen(name), sha1);
+       ret = get_sha1_1(name, strlen(name), sha1);
+       if (ret < 0) {
+               const char *cp = strchr(name, ':');
+               if (cp) {
+                       unsigned char tree_sha1[20];
+                       if (!get_sha1_1(name, cp-name, tree_sha1))
+                               return get_tree_entry(tree_sha1, cp+1, sha1);
+               }
+       }
+       return ret;
 }