Implement blob ID validation in fast-import.

When accepting revision SHA1 IDs from the frontend verify the SHA1
actually refers to a blob and is known to exist.  Its an error
to use a SHA1 in a tree if the blob doesn't exist as this would
cause git-fsck-objects to report a missing blob should the pack get
closed without the blob being appended into it or a subsequent pack.
So right now we'll just ask that the frontend "pre-declare" any
blobs it wants to use in a tree before it can use them.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

diff --git a/fast-import.c b/fast-import.c
index 4605b7469bb8e9c19e340c04d6703c6b8d1c9db7..95b84f57e50fad863c65c52e940d730235fd7616 100644 (file)
--- a/fast-import.c
+++ b/fast-import.c
@@ -70,6 +70,7 @@ Format of STDIN stream:
 struct object_entry
 {
        struct object_entry *next;
+       enum object_type type;
        unsigned long offset;
        unsigned char sha1[20];
 };
@@ -528,6 +529,7 @@ static int store_object(
                duplicate_count_by_type[type]++;
                return 1;
        }
+       e->type = type;
        e->offset = pack_offset;
        object_count++;
        object_count_by_type[type]++;
@@ -713,7 +715,7 @@ static int tree_content_set(
                        }
                        if (!S_ISDIR(e->mode)) {
                                e->tree = new_tree_content(8);
-                               e->mode = 040000;
+                               e->mode = S_IFDIR;
                        }
                        if (!e->tree)
                                load_tree(e);
@@ -732,7 +734,7 @@ static int tree_content_set(
        t->entries[t->entry_count++] = e;
        if (slash1) {
                e->tree = new_tree_content(8);
-               e->mode = 040000;
+               e->mode = S_IFDIR;
                tree_content_set(e, slash1 + 1, sha1, mode);
        } else {
                e->tree = NULL;
@@ -948,16 +950,28 @@ static void load_branch(struct branch *b)
 static void file_change_m(struct branch *b)
 {
        const char *path = read_path();
+       struct object_entry *oe;
        char hexsha1[41];
        unsigned char sha1[20];
+       char type[20];
 
        yread(0, hexsha1, 40);
        hexsha1[40] = 0;
 
        if (get_sha1_hex(hexsha1, sha1))
                die("Invalid sha1 %s for %s", hexsha1, path);
+       oe = find_object(sha1);
+       if (oe) {
+               if (oe->type != OBJ_BLOB)
+                       die("%s is a %s not a blob (for %s)", hexsha1, type_names[oe->type], path);
+       } else {
+               if (sha1_object_info(sha1, type, NULL))
+                       die("No blob %s for %s", hexsha1, path);
+               if (strcmp(blob_type, type))
+                       die("%s is a %s not a blob (for %s)", hexsha1, type, path);
+       }
 
-       tree_content_set(&b->branch_tree, path, sha1, 0100644);
+       tree_content_set(&b->branch_tree, path, sha1, S_IFREG | 0644);
 }
 
 static void file_change_d(struct branch *b)
@@ -986,6 +1000,10 @@ static void cmd_new_commit()
        c = body + max_hdr_len;
        yread(0, c, acmsglen);
 
+       /* oddly enough this is all that fsck-objects cares about */
+       if (memcmp(c, "author ", 7))
+               die("Invalid commit format on branch %s", name);
+
        /* file_change* */
        for (;;) {
                unsigned char cmd;
@@ -1104,7 +1122,9 @@ int main(int argc, const char **argv)
        fprintf(stderr, "      tags   :   %10lu (%10lu duplicates)\n", object_count_by_type[OBJ_TAG], duplicate_count_by_type[OBJ_TAG]);
        fprintf(stderr, "Total branches:  %10lu\n", branch_count);
        fprintf(stderr, "Total atoms:     %10u\n", atom_cnt);
-       fprintf(stderr, "Memory pools:    %10lu MiB\n", total_allocd/(1024*1024));
+       fprintf(stderr, "Memory total:    %10lu KiB\n", (total_allocd + alloc_count*sizeof(struct object_entry))/1024);
+       fprintf(stderr, "       pools:    %10lu KiB\n", total_allocd/1024);
+       fprintf(stderr, "     objects:    %10lu KiB\n", (alloc_count*sizeof(struct object_entry))/1024);
        fprintf(stderr, "---------------------------------------------------\n");
 
        stat(pack_name, &sb);