From: David Turner <[email protected]>

This wires the in-repo-symlink following code through to the cat-file
builtin.  In the event of an out-of-repo link, cat-file will print
the link in a new format.

Signed-off-by: David Turner <[email protected]>
---
 Documentation/git-cat-file.txt |  54 +++++++++++-
 builtin/cat-file.c             |  24 +++++-
 t/t1006-cat-file.sh            | 189 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 262 insertions(+), 5 deletions(-)

diff --git a/Documentation/git-cat-file.txt b/Documentation/git-cat-file.txt
index f6a16f4..9bdfced 100644
--- a/Documentation/git-cat-file.txt
+++ b/Documentation/git-cat-file.txt
@@ -10,7 +10,7 @@ SYNOPSIS
 --------
 [verse]
 'git cat-file' (-t | -s | -e | -p | <type> | --textconv ) <object>
-'git cat-file' (--batch | --batch-check) < <list-of-objects>
+'git cat-file' (--batch | --batch-check) [--follow-symlinks] < 
<list-of-objects>
 
 DESCRIPTION
 -----------
@@ -69,6 +69,46 @@ OPTIONS
        not be combined with any other options or arguments.  See the
        section `BATCH OUTPUT` below for details.
 
+--follow-symlinks::
+       Follow symlinks inside the repository when requesting objects
+       with extended SHA-1 expressions of the form tree-ish:path-in-tree.
+       Instead of providing output about the link itself, provide output
+       about the linked-to object.  This option requires --batch or
+       --batch-check.  In the event of a symlink loop (or more than
+       40 symlinks in a symlink resolution chain), the file will be
+       treated as missing.  If a symlink points outside the tree-ish
+       (e.g. a link to /foo or a root-level link to ../foo), the
+       portion of the link which is outside the tree will be printed.
+       Follow-symlinks will be silently turned off if <object>
+       specifies an object in the index rather than one in the object
+       database.
+
+       For example, consider the a git repository containing:
+       f: a file containing "hello\n"
+       link: a symlink to f
+       dir/link: a symlink to ../f
+       plink: a symlink to ../f
+       alink: a symlink to /etc/passwd
+
+       echo HEAD:f |git cat-file --batch --follow-symlinks would print
+       ce013625030ba8dba906f756967f9e9ca394464a blob 6
+
+       echo HEAD:link |git cat-file --batch --follow-symlinks would print
+       the same thing, as would HEAD:dir/link.
+       Without follow-symlinks, these would print data about the
+       symlink itself.  In the case of HEAD:link, you would see
+       4d1ae35ba2c8ec712fa2a379db44ad639ca277bd blob 1
+
+       Both plink and alink point outside the tree, so they would
+       respectively print:
+       symlink 4
+       ../f
+
+       symlink 11
+       /etc/passwd
+
+
+
 OUTPUT
 ------
 If '-t' is specified, one of the <type>.
@@ -148,6 +188,18 @@ the repository, then `cat-file` will ignore any custom 
format and print:
 <object> SP missing LF
 ------------
 
+If --follow-symlinks is used, and a symlink in the repository points
+outside the repository, then `cat-file` will ignore any custom format
+and print:
+
+------------
+symlink SP <size> LF <symlink> LF
+------------
+
+The symlink will either be absolute (beginning with a /), or relative
+to the tree root.  For instance, if dir/link points to ../../foo, then
+<symlink> will be ../foo.  <size> is the size of the symlink in bytes.
+
 
 CAVEATS
 -------
diff --git a/builtin/cat-file.c b/builtin/cat-file.c
index df99df4..6bcf9a0 100644
--- a/builtin/cat-file.c
+++ b/builtin/cat-file.c
@@ -224,6 +224,7 @@ static void print_object_or_die(int fd, struct expand_data 
*data)
 
 struct batch_options {
        int enabled;
+       int follow_symlinks;
        int print_contents;
        const char *format;
 };
@@ -232,16 +233,25 @@ static int batch_one_object(const char *obj_name, struct 
batch_options *opt,
                            struct expand_data *data)
 {
        struct strbuf buf = STRBUF_INIT;
+       struct object_context ctx;
+       int flags = opt->follow_symlinks ? GET_SHA1_FOLLOW_SYMLINKS : 0;
 
        if (!obj_name)
           return 1;
 
-       if (get_sha1(obj_name, data->sha1)) {
+       if (get_sha1_with_context(obj_name, flags, data->sha1, &ctx)) {
                printf("%s missing\n", obj_name);
                fflush(stdout);
                return 0;
        }
 
+       if (ctx.mode == 0) {
+               printf("symlink %"PRIuMAX"\n%s\n",
+                      (uintmax_t)ctx.symlink_path.len,
+                      ctx.symlink_path.buf);
+               return 0;
+       }
+
        if (sha1_object_info_extended(data->sha1, &data->info, 
LOOKUP_REPLACE_OBJECT) < 0) {
                printf("%s missing\n", obj_name);
                fflush(stdout);
@@ -342,9 +352,8 @@ static int batch_option_callback(const struct option *opt,
 {
        struct batch_options *bo = opt->value;
 
-       if (unset) {
-               memset(bo, 0, sizeof(*bo));
-               return 0;
+       if (bo->enabled) {
+               return 1;
        }
 
        bo->enabled = 1;
@@ -369,6 +378,9 @@ int cmd_cat_file(int argc, const char **argv, const char 
*prefix)
                OPT_SET_INT('p', NULL, &opt, N_("pretty-print object's 
content"), 'p'),
                OPT_SET_INT(0, "textconv", &opt,
                            N_("for blob objects, run textconv on object's 
content"), 'c'),
+               OPT_SET_INT(0, "follow-symlinks", &batch.follow_symlinks,
+                       N_("follow in-repo symlinks; report out-of-repo 
symlinks (requires --batch or --batch-check)"),
+                           1),
                { OPTION_CALLBACK, 0, "batch", &batch, "format",
                        N_("show info and content of objects fed from the 
standard input"),
                        PARSE_OPT_OPTARG, batch_option_callback },
@@ -402,6 +414,10 @@ int cmd_cat_file(int argc, const char **argv, const char 
*prefix)
                usage_with_options(cat_file_usage, options);
        }
 
+       if (batch.follow_symlinks && !batch.enabled) {
+               usage_with_options(cat_file_usage, options);
+       }
+
        if (batch.enabled)
                return batch_objects(&batch);
 
diff --git a/t/t1006-cat-file.sh b/t/t1006-cat-file.sh
index ab36b1e..b863a68 100755
--- a/t/t1006-cat-file.sh
+++ b/t/t1006-cat-file.sh
@@ -189,6 +189,13 @@ do
     '
 done
 
+for opt in t s e p
+do
+    test_expect_success "Passing -$opt with --follow-symlinks fails" '
+           test_must_fail git cat-file --follow-symlinks -$opt $hello_sha1
+       '
+done
+
 test_expect_success "--batch-check for a non-existent named object" '
     test "foobar42 missing
 foobar84 missing" = \
@@ -296,4 +303,186 @@ test_expect_success '%(deltabase) reports packed delta 
bases' '
        }
 '
 
+# Tests for git cat-file --follow-symlinks
+test_expect_success 'prep for symlink tests' '
+       echo_without_newline "$hello_content" >morx &&
+       test_ln_s_add morx same-dir-link &&
+       test_ln_s_add ../fleem out-of-repo-link &&
+       test_ln_s_add .. out-of-repo-link-dir &&
+       test_ln_s_add same-dir-link link-to-link &&
+       test_ln_s_add nope broken-same-dir-link &&
+       mkdir dir &&
+       test_ln_s_add ../morx dir/parent-dir-link &&
+       test_ln_s_add .. dir/link-dir &&
+       test_ln_s_add ../../escape dir/out-of-repo-link &&
+       test_ln_s_add ../.. dir/out-of-repo-link-dir &&
+       test_ln_s_add nope dir/broken-link-in-dir &&
+       mkdir dir/subdir &&
+       test_ln_s_add ../../morx dir/subdir/grandparent-dir-link &&
+       test_ln_s_add ../../../great-escape dir/subdir/out-of-repo-link &&
+       test_ln_s_add ../../.. dir/subdir/out-of-repo-link-dir &&
+       test_ln_s_add ../../../ dir/subdir/out-of-repo-link-dir-trailing &&
+       test_ln_s_add ../parent-dir-link dir/subdir/parent-dir-link-to-link &&
+       echo_without_newline "$hello_content" >dir/subdir/ind2 &&
+       echo_without_newline "$hello_content" >dir/ind1 &&
+       test_ln_s_add dir dirlink &&
+       test_ln_s_add dir/subdir subdirlink &&
+       test_ln_s_add subdir/ind2 dir/link-to-child &&
+       test_ln_s_add dir/link-to-child link-to-down-link &&
+       test_ln_s_add dir/.. up-down &&
+       test_ln_s_add dir/../ up-down-trailing &&
+       test_ln_s_add dir/../morx up-down-file &&
+       test_ln_s_add dir/../../morx up-up-down-file &&
+       test_ln_s_add subdirlink/../../morx up-two-down-file &&
+       test_ln_s_add loop1 loop2 &&
+       test_ln_s_add loop2 loop1 &&
+       git add morx dir/subdir/ind2 dir/ind1 &&
+       git commit -am "test" &&
+       echo $hello_sha1 blob $hello_size >found
+'
+
+test_expect_success 'git cat-file --batch-check --follow-symlinks works for 
non-links' '
+       echo HEAD:morx | git cat-file --batch-check --follow-symlinks >actual &&
+       test_cmp found actual &&
+       echo HEAD:nope missing >expect &&
+       echo HEAD:nope | git cat-file --batch-check --follow-symlinks >actual &&
+       test_cmp expect actual
+'
+
+test_expect_success 'git cat-file --batch-check --follow-symlinks works for 
in-repo, same-dir links' '
+       echo HEAD:same-dir-link | git cat-file --batch-check --follow-symlinks 
>actual &&
+       test_cmp found actual
+'
+
+test_expect_success 'git cat-file --batch-check --follow-symlinks works for 
broken in-repo, same-dir links' '
+       echo HEAD:broken-same-dir-link missing >expect &&
+       echo HEAD:broken-same-dir-link | git cat-file --batch-check 
--follow-symlinks >actual &&
+       test_cmp expect actual
+'
+
+test_expect_success 'git cat-file --batch-check --follow-symlinks works for 
same-dir links-to-links' '
+       echo HEAD:link-to-link | git cat-file --batch-check --follow-symlinks 
>actual &&
+       test_cmp found actual
+'
+
+test_expect_success 'git cat-file --batch-check --follow-symlinks works for 
parent-dir links' '
+       echo HEAD:dir/parent-dir-link | git cat-file --batch-check 
--follow-symlinks >actual &&
+       test_cmp found actual &&
+       echo HEAD:dir/parent-dir-link/nope missing >expect &&
+       echo HEAD:dir/parent-dir-link/nope | git cat-file --batch-check 
--follow-symlinks >actual &&
+       test_cmp expect actual
+'
+
+test_expect_success 'git cat-file --batch-check --follow-symlinks works for .. 
links' '
+       echo HEAD:dir/link-dir/nope missing >expect &&
+       echo HEAD:dir/link-dir/nope | git cat-file --batch-check 
--follow-symlinks >actual &&
+       test_cmp expect actual &&
+       echo HEAD:dir/link-dir/morx | git cat-file --batch-check 
--follow-symlinks >actual &&
+       test_cmp found actual &&
+       echo HEAD:dir/broken-link-in-dir missing >expect &&
+       echo HEAD:dir/broken-link-in-dir | git cat-file --batch-check 
--follow-symlinks >actual &&
+       test_cmp expect actual
+'
+
+test_expect_success 'git cat-file --batch-check --follow-symlinks works for 
../.. links' '
+       echo HEAD:dir/subdir/grandparent-dir-link/nope missing >expect &&
+       echo HEAD:dir/subdir/grandparent-dir-link/nope | git cat-file 
--batch-check --follow-symlinks >actual &&
+       test_cmp expect actual &&
+       echo HEAD:dir/subdir/grandparent-dir-link | git cat-file --batch-check 
--follow-symlinks >actual &&
+       test_cmp found actual &&
+       echo HEAD:dir/subdir/parent-dir-link-to-link | git cat-file 
--batch-check --follow-symlinks >actual &&
+       test_cmp found actual
+'
+
+test_expect_success 'git cat-file --batch-check --follow-symlinks works for 
dir/ links' '
+       echo HEAD:dirlink/morx missing >expect &&
+       echo HEAD:dirlink/morx | git cat-file --batch-check --follow-symlinks 
>actual &&
+       test_cmp expect actual &&
+       echo $hello_sha1 blob $hello_size >expect &&
+       echo HEAD:dirlink/ind1 | git cat-file --batch-check --follow-symlinks 
>actual &&
+       test_cmp expect actual
+'
+
+test_expect_success 'git cat-file --batch-check --follow-symlinks works for 
dir/subdir links' '
+       echo HEAD:subdirlink/morx missing >expect &&
+       echo HEAD:subdirlink/morx | git cat-file --batch-check 
--follow-symlinks >actual &&
+       test_cmp expect actual &&
+       echo HEAD:subdirlink/ind2 | git cat-file --batch-check 
--follow-symlinks >actual &&
+       test_cmp found actual
+'
+
+test_expect_success 'git cat-file --batch-check --follow-symlinks works for 
dir ->subdir links' '
+       echo HEAD:dir/link-to-child/morx missing >expect &&
+       echo HEAD:dir/link-to-child/morx | git cat-file --batch-check 
--follow-symlinks >actual &&
+       test_cmp expect actual &&
+       echo HEAD:dir/link-to-child | git cat-file --batch-check 
--follow-symlinks >actual &&
+       test_cmp found actual &&
+       echo HEAD:link-to-down-link | git cat-file --batch-check 
--follow-symlinks >actual &&
+       test_cmp found actual
+'
+
+test_expect_success 'git cat-file --batch-check --follow-symlinks works for 
out-of-repo symlinks' '
+       echo symlink 8 >expect &&
+       echo ../fleem >>expect &&
+       echo HEAD:out-of-repo-link | git cat-file --batch-check 
--follow-symlinks >actual &&
+       test_cmp expect actual &&
+       echo symlink 2 >expect &&
+       echo .. >>expect &&
+       echo HEAD:out-of-repo-link-dir | git cat-file --batch-check 
--follow-symlinks >actual &&
+       test_cmp expect actual
+'
+
+test_expect_success 'git cat-file --batch-check --follow-symlinks works for 
out-of-repo symlinks in dirs' '
+       echo symlink 9 >expect &&
+       echo ../escape >>expect &&
+       echo HEAD:dir/out-of-repo-link | git cat-file --batch-check 
--follow-symlinks >actual &&
+       test_cmp expect actual &&
+       echo symlink 2 >expect &&
+       echo .. >>expect &&
+       echo HEAD:dir/out-of-repo-link-dir | git cat-file --batch-check 
--follow-symlinks >actual &&
+       test_cmp expect actual
+'
+
+test_expect_success 'git cat-file --batch-check --follow-symlinks works for 
out-of-repo symlinks in subdirs' '
+       echo symlink 15 >expect &&
+       echo ../great-escape >>expect &&
+       echo HEAD:dir/subdir/out-of-repo-link | git cat-file --batch-check 
--follow-symlinks >actual &&
+       test_cmp expect actual &&
+       echo symlink 2 >expect &&
+       echo .. >>expect &&
+       echo HEAD:dir/subdir/out-of-repo-link-dir | git cat-file --batch-check 
--follow-symlinks >actual &&
+       test_cmp expect actual &&
+       echo symlink 3 >expect &&
+       echo ../ >>expect &&
+       echo HEAD:dir/subdir/out-of-repo-link-dir-trailing | git cat-file 
--batch-check --follow-symlinks >actual &&
+       test_cmp expect actual
+'
+
+test_expect_success 'git cat-file --batch-check --follow-symlinks works for 
symlinks with internal ..' '
+       echo HEAD: | git cat-file --batch-check >expect &&
+       echo HEAD:up-down | git cat-file --batch-check --follow-symlinks 
>actual &&
+       test_cmp expect actual &&
+       echo HEAD:up-down-trailing | git cat-file --batch-check 
--follow-symlinks >actual &&
+       test_cmp expect actual &&
+       echo HEAD:up-down-file | git cat-file --batch-check --follow-symlinks 
>actual &&
+       test_cmp found actual &&
+       echo symlink 7 >expect &&
+       echo ../morx >>expect &&
+       echo HEAD:up-up-down-file | git cat-file --batch-check 
--follow-symlinks >actual &&
+       test_cmp expect actual &&
+       echo HEAD:up-two-down-file | git cat-file --batch-check 
--follow-symlinks >actual &&
+       test_cmp found actual
+'
+
+test_expect_success 'git cat-file --batch-check --follow-symlink breaks loops' 
'
+       echo HEAD:loop1 missing >expect &&
+       echo HEAD:loop1 | git cat-file --batch-check --follow-symlinks >actual 
&&
+       test_cmp expect actual
+'
+
+test_expect_success 'git cat-file --batch --follow-symlink returns correct sha 
and mode' '
+       echo HEAD:morx | git cat-file --batch >expect &&
+       echo HEAD:morx | git cat-file --batch --follow-symlinks >actual &&
+       test_cmp expect actual
+'
 test_done
-- 
2.0.4.315.gad8727a-twtrsrc

--
To unsubscribe from this list: send the line "unsubscribe git" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
  • [PATCH v6 0/3] dturner
    • [PATCH v6 3/3] cat-file: add --follow-symlinks to --batch dturner

Reply via email to