From 8dc6a373d201839859fe7924b63e57526ee2fc22 Mon Sep 17 00:00:00 2001 From: David Barr Date: Thu, 2 Dec 2010 21:40:20 +1100 Subject: fast-import: add 'ls' command Lazy fast-import frontend authors that want to rely on the backend to keep track of the content of the imported trees _almost_ have what they need in the 'cat-blob' command (v1.7.4-rc0~30^2~3, 2010-11-28). But it is not quite enough, since (1) cat-blob can be used to retrieve the content of files, but not their mode, and (2) using cat-blob requires the frontend to keep track of a name (mark number or object id) for each blob to be retrieved Introduce an 'ls' command to complement cat-blob and take care of the remaining needs. The 'ls' command finds what is at a given path within a given tree-ish (tag, commit, or tree): 'ls' SP SP LF or in fast-import's active commit: 'ls' SP LF The response is a single line sent through the cat-blob channel, imitating ls-tree output. So for example: FE> ls :1 Documentation gfi> 040000 tree 9e6c2b599341d28a2a375f8207507e0a2a627fe9 Documentation FE> ls 9e6c2b599341d28a2a375f8207507e0a2a627fe9 git-fast-import.txt gfi> 100644 blob 4f92954396e3f0f97e75b6838a5635b583708870 git-fast-import.txt FE> ls :1 RelNotes gfi> 120000 blob b942e499449d97aeb50c73ca2bdc1c6e6d528743 RelNotes FE> cat-blob b942e499449d97aeb50c73ca2bdc1c6e6d528743 gfi> b942e499449d97aeb50c73ca2bdc1c6e6d528743 blob 32 gfi> Documentation/RelNotes/1.7.4.txt The most interesting parts of the reply are the first word, which is a 6-digit octal mode (regular file, executable, symlink, directory, or submodule), and the part from the second space to the tab, which is a that can be used in later cat-blob, ls, and filemodify (M) commands to refer to the content (blob, tree, or commit) at that path. If there is nothing there, the response is "missing some/path". The intent is for this command to be used to read files from the active commit, so a frontend can apply patches to them, and to copy files and directories from previous revisions. For example, proposed updates to svn-fe use this command in place of its internal representation of the repository directory structure. This simplifies the frontend a great deal and means support for resuming an import in a separate fast-import run (i.e., incremental import) is basically free. Signed-off-by: David Barr Signed-off-by: Jonathan Nieder Improved-by: Junio C Hamano Improved-by: Sverre Rabbelier --- fast-import.c | 162 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 159 insertions(+), 3 deletions(-) (limited to 'fast-import.c') diff --git a/fast-import.c b/fast-import.c index 3886a1b464..6c37b8400a 100644 --- a/fast-import.c +++ b/fast-import.c @@ -24,10 +24,12 @@ Format of STDIN stream: commit_msg ('from' sp committish lf)? ('merge' sp committish lf)* - file_change* + (file_change | ls)* lf?; commit_msg ::= data; + ls ::= 'ls' sp '"' quoted(path) '"' lf; + file_change ::= file_clr | file_del | file_rnm @@ -132,7 +134,7 @@ Format of STDIN stream: ts ::= # time since the epoch in seconds, ascii base10 notation; tz ::= # GIT style timezone; - # note: comments and cat requests may appear anywhere + # note: comments, ls and cat requests may appear anywhere # in the input, except within a data command. Any form # of the data command always escapes the related input # from comment processing. @@ -141,7 +143,9 @@ Format of STDIN stream: # must be the first character on that line (an lf # preceded it). # + cat_blob ::= 'cat-blob' sp (hexsha1 | idnum) lf; + ls_tree ::= 'ls' sp (hexsha1 | idnum) sp path_str lf; comment ::= '#' not_lf* lf; not_lf ::= # Any byte that is not ASCII newline (LF); @@ -374,6 +378,7 @@ static int cat_blob_fd = STDOUT_FILENO; static void parse_argv(void); static void parse_cat_blob(void); +static void parse_ls(struct branch *b); static void write_branch_report(FILE *rpt, struct branch *b) { @@ -2614,6 +2619,8 @@ static void parse_new_commit(void) note_change_n(b, prev_fanout); else if (!strcmp("deleteall", command_buf.buf)) file_change_deleteall(b); + else if (!prefixcmp(command_buf.buf, "ls ")) + parse_ls(b); else { unread_command_buf = 1; break; @@ -2837,6 +2844,153 @@ static void parse_cat_blob(void) cat_blob(oe, sha1); } +static struct object_entry *dereference(struct object_entry *oe, + unsigned char sha1[20]) +{ + unsigned long size; + void *buf = NULL; + if (!oe) { + enum object_type type = sha1_object_info(sha1, NULL); + if (type < 0) + die("object not found: %s", sha1_to_hex(sha1)); + /* cache it! */ + oe = insert_object(sha1); + oe->type = type; + oe->pack_id = MAX_PACK_ID; + oe->idx.offset = 1; + } + switch (oe->type) { + case OBJ_TREE: /* easy case. */ + return oe; + case OBJ_COMMIT: + case OBJ_TAG: + break; + default: + die("Not a treeish: %s", command_buf.buf); + } + + if (oe->pack_id != MAX_PACK_ID) { /* in a pack being written */ + buf = gfi_unpack_entry(oe, &size); + } else { + enum object_type unused; + buf = read_sha1_file(sha1, &unused, &size); + } + if (!buf) + die("Can't load object %s", sha1_to_hex(sha1)); + + /* Peel one layer. */ + switch (oe->type) { + case OBJ_TAG: + if (size < 40 + strlen("object ") || + get_sha1_hex(buf + strlen("object "), sha1)) + die("Invalid SHA1 in tag: %s", command_buf.buf); + break; + case OBJ_COMMIT: + if (size < 40 + strlen("tree ") || + get_sha1_hex(buf + strlen("tree "), sha1)) + die("Invalid SHA1 in commit: %s", command_buf.buf); + } + + free(buf); + return find_object(sha1); +} + +static struct object_entry *parse_treeish_dataref(const char **p) +{ + unsigned char sha1[20]; + struct object_entry *e; + + if (**p == ':') { /* */ + char *endptr; + e = find_mark(strtoumax(*p + 1, &endptr, 10)); + if (endptr == *p + 1) + die("Invalid mark: %s", command_buf.buf); + if (!e) + die("Unknown mark: %s", command_buf.buf); + *p = endptr; + hashcpy(sha1, e->idx.sha1); + } else { /* */ + if (get_sha1_hex(*p, sha1)) + die("Invalid SHA1: %s", command_buf.buf); + e = find_object(sha1); + *p += 40; + } + + while (!e || e->type != OBJ_TREE) + e = dereference(e, sha1); + return e; +} + +static void print_ls(int mode, const unsigned char *sha1, const char *path) +{ + static struct strbuf line = STRBUF_INIT; + + /* See show_tree(). */ + const char *type = + S_ISGITLINK(mode) ? commit_type : + S_ISDIR(mode) ? tree_type : + blob_type; + + if (!mode) { + /* missing SP path LF */ + strbuf_reset(&line); + strbuf_addstr(&line, "missing "); + quote_c_style(path, &line, NULL, 0); + strbuf_addch(&line, '\n'); + } else { + /* mode SP type SP object_name TAB path LF */ + strbuf_reset(&line); + strbuf_addf(&line, "%06o %s %s\t", + mode, type, sha1_to_hex(sha1)); + quote_c_style(path, &line, NULL, 0); + strbuf_addch(&line, '\n'); + } + cat_blob_write(line.buf, line.len); +} + +static void parse_ls(struct branch *b) +{ + const char *p; + struct tree_entry *root = NULL; + struct tree_entry leaf = {0}; + + /* ls SP ( SP)? */ + p = command_buf.buf + strlen("ls "); + if (*p == '"') { + if (!b) + die("Not in a commit: %s", command_buf.buf); + root = &b->branch_tree; + } else { + struct object_entry *e = parse_treeish_dataref(&p); + root = new_tree_entry(); + hashcpy(root->versions[1].sha1, e->idx.sha1); + load_tree(root); + if (*p++ != ' ') + die("Missing space after tree-ish: %s", command_buf.buf); + } + if (*p == '"') { + static struct strbuf uq = STRBUF_INIT; + const char *endp; + strbuf_reset(&uq); + if (unquote_c_style(&uq, p, &endp)) + die("Invalid path: %s", command_buf.buf); + if (*endp) + die("Garbage after path in: %s", command_buf.buf); + p = uq.buf; + } + tree_content_get(root, p, &leaf); + /* + * A directory in preparation would have a sha1 of zero + * until it is saved. Save, for simplicity. + */ + if (S_ISDIR(leaf.versions[1].mode)) + store_tree(&leaf); + + print_ls(leaf.versions[1].mode, leaf.versions[1].sha1, p); + if (!b || root != &b->branch_tree) + release_tree_entry(root); +} + static void checkpoint(void) { checkpoint_requested = 0; @@ -3001,7 +3155,7 @@ static int parse_one_feature(const char *feature, int from_stream) relative_marks_paths = 0; } else if (!prefixcmp(feature, "force")) { force_update = 1; - } else if (!strcmp(feature, "notes")) { + } else if (!strcmp(feature, "notes") || !strcmp(feature, "ls")) { ; /* do nothing; we have the feature */ } else { return 0; @@ -3142,6 +3296,8 @@ int main(int argc, const char **argv) while (read_next_command() != EOF) { if (!strcmp("blob", command_buf.buf)) parse_new_blob(); + else if (!prefixcmp(command_buf.buf, "ls ")) + parse_ls(NULL); else if (!prefixcmp(command_buf.buf, "commit ")) parse_new_commit(); else if (!prefixcmp(command_buf.buf, "tag ")) -- cgit 1.2.3-korg