fast-import: let importers retrieve blobs
[gitweb.git] / fast-import.c
index 2317b0fe7509b957577234890135509143c0872b..dd58f517b9f0e30fcd232afffbdeca1831b1b1e2 100644 (file)
@@ -55,6 +55,8 @@ Format of STDIN stream:
     ('from' sp committish lf)?
     lf?;
 
+  cat_blob ::= 'cat-blob' sp (hexsha1 | idnum) lf;
+
   checkpoint ::= 'checkpoint' lf
     lf?;
 
@@ -361,6 +363,9 @@ static uintmax_t next_mark;
 static struct strbuf new_data = STRBUF_INIT;
 static int seen_data_command;
 
+/* Where to write output of cat-blob commands */
+static int cat_blob_fd = STDOUT_FILENO;
+
 static void parse_argv(void);
 
 static void write_branch_report(FILE *rpt, struct branch *b)
@@ -1454,6 +1459,15 @@ static int tree_content_set(
                n = slash1 - p;
        else
                n = strlen(p);
+       if (!slash1 && !n) {
+               if (!S_ISDIR(mode))
+                       die("Root cannot be a non-directory");
+               hashcpy(root->versions[1].sha1, sha1);
+               if (root->tree)
+                       release_tree_content_recursive(root->tree);
+               root->tree = subtree;
+               return 1;
+       }
        if (!n)
                die("Empty path component found in input");
        if (!slash1 && !S_ISDIR(mode) && subtree)
@@ -2680,6 +2694,81 @@ static void parse_reset_branch(void)
                unread_command_buf = 1;
 }
 
+static void cat_blob_write(const char *buf, unsigned long size)
+{
+       if (write_in_full(cat_blob_fd, buf, size) != size)
+               die_errno("Write to frontend failed");
+}
+
+static void cat_blob(struct object_entry *oe, unsigned char sha1[20])
+{
+       struct strbuf line = STRBUF_INIT;
+       unsigned long size;
+       enum object_type type = 0;
+       char *buf;
+
+       if (!oe || oe->pack_id == MAX_PACK_ID) {
+               buf = read_sha1_file(sha1, &type, &size);
+       } else {
+               type = oe->type;
+               buf = gfi_unpack_entry(oe, &size);
+       }
+
+       /*
+        * Output based on batch_one_object() from cat-file.c.
+        */
+       if (type <= 0) {
+               strbuf_reset(&line);
+               strbuf_addf(&line, "%s missing\n", sha1_to_hex(sha1));
+               cat_blob_write(line.buf, line.len);
+               strbuf_release(&line);
+               free(buf);
+               return;
+       }
+       if (!buf)
+               die("Can't read object %s", sha1_to_hex(sha1));
+       if (type != OBJ_BLOB)
+               die("Object %s is a %s but a blob was expected.",
+                   sha1_to_hex(sha1), typename(type));
+       strbuf_reset(&line);
+       strbuf_addf(&line, "%s %s %lu\n", sha1_to_hex(sha1),
+                                               typename(type), size);
+       cat_blob_write(line.buf, line.len);
+       strbuf_release(&line);
+       cat_blob_write(buf, size);
+       cat_blob_write("\n", 1);
+       free(buf);
+}
+
+static void parse_cat_blob(void)
+{
+       const char *p;
+       struct object_entry *oe = oe;
+       unsigned char sha1[20];
+
+       /* cat-blob SP <object> LF */
+       p = command_buf.buf + strlen("cat-blob ");
+       if (*p == ':') {
+               char *x;
+               oe = find_mark(strtoumax(p + 1, &x, 10));
+               if (x == p + 1)
+                       die("Invalid mark: %s", command_buf.buf);
+               if (!oe)
+                       die("Unknown mark: %s", command_buf.buf);
+               if (*x)
+                       die("Garbage after mark: %s", command_buf.buf);
+               hashcpy(sha1, oe->idx.sha1);
+       } else {
+               if (get_sha1_hex(p, sha1))
+                       die("Invalid SHA1: %s", command_buf.buf);
+               if (p[40])
+                       die("Garbage after SHA1: %s", command_buf.buf);
+               oe = find_object(sha1);
+       }
+
+       cat_blob(oe, sha1);
+}
+
 static void parse_checkpoint(void)
 {
        if (object_count) {
@@ -2737,16 +2826,25 @@ static void option_date_format(const char *fmt)
                die("unknown --date-format argument %s", fmt);
 }
 
+static unsigned long ulong_arg(const char *option, const char *arg)
+{
+       char *endptr;
+       unsigned long rv = strtoul(arg, &endptr, 0);
+       if (strchr(arg, '-') || endptr == arg || *endptr)
+               die("%s: argument must be a non-negative integer", option);
+       return rv;
+}
+
 static void option_depth(const char *depth)
 {
-       max_depth = strtoul(depth, NULL, 0);
+       max_depth = ulong_arg("--depth", depth);
        if (max_depth > MAX_DEPTH)
                die("--depth cannot exceed %u", MAX_DEPTH);
 }
 
 static void option_active_branches(const char *branches)
 {
-       max_active_branches = strtoul(branches, NULL, 0);
+       max_active_branches = ulong_arg("--active-branches", branches);
 }
 
 static void option_export_marks(const char *marks)
@@ -2755,6 +2853,14 @@ static void option_export_marks(const char *marks)
        safe_create_leading_directories_const(export_marks_file);
 }
 
+static void option_cat_blob_fd(const char *fd)
+{
+       unsigned long n = ulong_arg("--cat-blob-fd", fd);
+       if (n > (unsigned long) INT_MAX)
+               die("--cat-blob-fd cannot exceed %d", INT_MAX);
+       cat_blob_fd = (int) n;
+}
+
 static void option_export_pack_edges(const char *edges)
 {
        if (pack_edges)
@@ -2808,6 +2914,8 @@ static int parse_one_feature(const char *feature, int from_stream)
                option_import_marks(feature + 13, from_stream);
        } else if (!prefixcmp(feature, "export-marks=")) {
                option_export_marks(feature + 13);
+       } else if (!strcmp(feature, "cat-blob")) {
+               ; /* Don't die - this feature is supported */
        } else if (!prefixcmp(feature, "relative-marks")) {
                relative_marks_paths = 1;
        } else if (!prefixcmp(feature, "no-relative-marks")) {
@@ -2884,7 +2992,7 @@ static int git_pack_config(const char *k, const char *v, void *cb)
 }
 
 static const char fast_import_usage[] =
-"git fast-import [--date-format=f] [--max-pack-size=n] [--big-file-threshold=n] [--depth=n] [--active-branches=n] [--export-marks=marks.file]";
+"git fast-import [--date-format=<f>] [--max-pack-size=<n>] [--big-file-threshold=<n>] [--depth=<n>] [--active-branches=<n>] [--export-marks=<marks.file>]";
 
 static void parse_argv(void)
 {
@@ -2902,6 +3010,11 @@ static void parse_argv(void)
                if (parse_one_feature(a + 2, 0))
                        continue;
 
+               if (!prefixcmp(a + 2, "cat-blob-fd=")) {
+                       option_cat_blob_fd(a + 2 + strlen("cat-blob-fd="));
+                       continue;
+               }
+
                die("unknown option %s", a);
        }
        if (i != global_argc)
@@ -2953,6 +3066,8 @@ int main(int argc, const char **argv)
                        parse_new_tag();
                else if (!prefixcmp(command_buf.buf, "reset "))
                        parse_reset_branch();
+               else if (!prefixcmp(command_buf.buf, "cat-blob "))
+                       parse_cat_blob();
                else if (!strcmp("checkpoint", command_buf.buf))
                        parse_checkpoint();
                else if (!prefixcmp(command_buf.buf, "progress "))