On 08/21/2013 10:56 PM, Junio C Hamano wrote:
> Stefan Beller <stefanbeller@xxxxxxxxxxxxxx> writes:
>
>> The motivation of this patch is to get closer to a goal of being
>> able to have a core subset of git functionality built in to git.
>> That would mean
>>
>> * people on Windows could get a copy of at least the core parts
>> of Git without having to install a Unix-style shell
>>
>> * people deploying to servers don't have to rewrite the #! line
>> or worry about the PATH and quality of installed POSIX
>> utilities, if they are only using the built-in part written
>> in C
>
> I am not sure what is meant by the latter. Rewriting #! is part of
> any scripted Porcelain done by the top-level Makefile, and I do not
> think we have seen any problem reports on it.
>
> As to "quality of ... utilities", I think the real issue some people
> in the thread had was not about "deploying to servers" but about
> installing in a minimalistic chrooted environment where standard
> tools may be lacking.
>
>> diff --git a/builtin/repack.c b/builtin/repack.c
>> new file mode 100644
>> index 0000000..fb050c0
>> --- /dev/null
>> +++ b/builtin/repack.c
>> @@ -0,0 +1,376 @@
>> +/*
>> + * The shell version was written by Linus Torvalds (2005) and many others.
>> + * This is a translation into C by Stefan Beller (2013)
>> + */
>
> I am not sure if we want to record "ownership" in the code like
> this; it will go stale over time.
I'll remove it. Initially I put it there as I found similar
comments in other files as well.
>> +static int delta_base_offset = 1;
>> +char *packdir;
>
> Does this have to be global?
We could pass it to all the functions, making it not global.
I'd be ok with that for the functions get_pack_filenames
and remove_redundant_pack, but we also need to know
packdir in remove_temporary_files which is called from
the signal handler remove_pack_on_signal.
As the path is pretty obvious (get_object_directory() + "/pack"),
we could however also construct it again in the signal handler.
> So in summary:
>
> dir = opendir(packdir);
> if (!dir)
> return;
>
> strbuf_addf(&buf, "%s-", packtmp);
packtmp is not yet a global variable, but could be passed to
to this function. Currently we're reconstructing it here.
>
> /* Point at the slash at the end of ".../objects/pack/" */
> dirlen = strlen(packdir) + 1;
> /* Point at the dash at the end of ".../.tmp-%d-pack-" */
> prefixlen = buf.len - dirlen;
>
> You would need to move the initialization of packdir and packtmp
> before sigchain_push() in cmd_repack() if you were to do this.
Ah ok, I'll do so.
>> +
>> + if (!file_exists(mkpath("%s/%s.keep", packdir, fname)))
>> + string_list_append_nodup(fname_list, fname);
>
> mental note: this is getting names of non-kept packs, not all packs.
I should document that. ;)
>> + while (strbuf_getline(&line, out, '\n') != EOF) {
>> + if (line.len != 40)
>> + die("repack: Expecting 40 character sha1 lines only from pack-objects.");
>> + strbuf_addstr(&line, "");
>
> What is this addstr() about?
According to the documentation of strbufs, we cannot assume to have sane
strings, but anything. Adding an empty string however will make sure to
add a NUL-terminated string to the buffer, no?
In a previous roll of this patch, which operated on char* line,
there was just line[40] = '\0'; // replacing '\n' by '\0'
to have it sane in the string list.
>
>> + string_list_append(&names, line.buf);
>> + count_packs++;
>
> It probably is more in line with our naming convention to call this
> nr_packs, num_packs, etc. "count_packs" sounds more like a boolean
> that instructs the code to either count or not bother counting,
> which this thing is not.
This is something subtle, but important to know. Thanks, will be fixed in
the reroll.
>> +
>> + if (rename(fname, fname_old)) {
>> + failed = 1;
>> + break;
>
> "break"-ing from here leaks fname_old. As the only out-of-line call
> file_exists() is just a thin wrapper around lstat(), I think it is
> fine not to pathdup the fname_old here.
fixed
I'd really appreciate, if there was documentation on these functions.
(When is mkpath safe? What is better in which situation: mkpath or strbufs?)
Maybe I could start doing it (but only those functions I used so far,
there are many more in cache.h)
>
>> + }
>> + string_list_append_nodup(&rollback, fname);
>> + free(fname);
>
> This looks bad, doesn't it? append_nodup() lets &rollback string
> list to take the ownership of the piece of memory pointed at by
> fname, but then you free it here, no?
>
> If you initialize &rollback with INIT_NODUP, you would not have to
> call append_nodup().
Removed the free.
Having rollback initialized with NODUP and then not explicitely
using append_nodup() makes me feel unhappy, because now you need
to check different places to make sure there is no leaking memory,
(you need to know the list is NODUP). I changed it nevertheless,
maybe I feel enlightened later on. ;)
As Matthieu proposed, I also set
CFLAGS += -Wdeclaration-after-statement in config.mak now. Hopefully
I don't screw up again now.
Thanks,
Stefan
--8<--
From 79945f5ae45f08fa2dbabfa1f6b7cd0b344ec0b3 Mon Sep 17 00:00:00 2001
From: Stefan Beller <stefanbeller@xxxxxxxxxxxxxx>
Date: Thu, 22 Aug 2013 00:13:35 +0200
Subject: [PATCH] Suggestions by Junio
---
builtin/repack.c | 68 ++++++++++++++++++++++++++------------------------------
1 file changed, 31 insertions(+), 37 deletions(-)
diff --git a/builtin/repack.c b/builtin/repack.c
index 1f13e0d..bb90f07 100644
--- a/builtin/repack.c
+++ b/builtin/repack.c
@@ -1,8 +1,3 @@
-/*
- * The shell version was written by Linus Torvalds (2005) and many others.
- * This is a translation into C by Stefan Beller (2013)
- */
-
#include "builtin.h"
#include "cache.h"
#include "dir.h"
@@ -13,9 +8,8 @@
#include "string-list.h"
#include "argv-array.h"
-/* enabled by default since 22c79eab (2008-06-25) */
static int delta_base_offset = 1;
-char *packdir;
+char *packdir, *packtmp;
static const char *const git_repack_usage[] = {
N_("git repack [options]"),
@@ -41,18 +35,16 @@ static void remove_temporary_files(void)
DIR *dir;
struct dirent *e;
- /* .git/objects/pack */
- strbuf_addstr(&buf, get_object_directory());
- strbuf_addstr(&buf, "/pack");
- dir = opendir(buf.buf);
- if (!dir) {
- strbuf_release(&buf);
+ dir = opendir(packdir);
+ if (!dir)
return;
- }
- /* .git/objects/pack/.tmp-$$-pack-* */
+ strbuf_addstr(&buf, packdir);
+
+ /* dirlen holds the length of the path before the file name */
dirlen = buf.len + 1;
- strbuf_addf(&buf, "/.tmp-%d-pack-", (int)getpid());
+ strbuf_addf(&buf, "%s", packtmp);
+ /* prefixlen holds the length of the prefix */
prefixlen = buf.len - dirlen;
while ((e = readdir(dir))) {
@@ -73,11 +65,16 @@ static void remove_pack_on_signal(int signo)
raise(signo);
}
+/*
+ * Adds all packs hex strings to the fname list, which do not
+ * have a corresponding .keep file.
+ */
static void get_pack_filenames(struct string_list *fname_list)
{
DIR *dir;
struct dirent *e;
char *fname;
+ size_t len;
if (!(dir = opendir(packdir)))
return;
@@ -86,7 +83,7 @@ static void get_pack_filenames(struct string_list *fname_list)
if (suffixcmp(e->d_name, ".pack"))
continue;
- size_t len = strlen(e->d_name) - strlen(".pack");
+ len = strlen(e->d_name) - strlen(".pack");
fname = xmemdupz(e->d_name, len);
if (!file_exists(mkpath("%s/%s.keep", packdir, fname)))
@@ -95,14 +92,14 @@ static void get_pack_filenames(struct string_list *fname_list)
closedir(dir);
}
-static void remove_redundant_pack(const char *path, const char *sha1)
+static void remove_redundant_pack(const char *path_prefix, const char *hex)
{
const char *exts[] = {".pack", ".idx", ".keep"};
int i;
struct strbuf buf = STRBUF_INIT;
size_t plen;
- strbuf_addf(&buf, "%s/%s", path, sha1);
+ strbuf_addf(&buf, "%s/%s", path_prefix, hex);
plen = buf.len;
for (i = 0; i < ARRAY_SIZE(exts); i++) {
@@ -115,15 +112,14 @@ static void remove_redundant_pack(const char *path, const char *sha1)
int cmd_repack(int argc, const char **argv, const char *prefix)
{
const char *exts[2] = {".idx", ".pack"};
- char *packtmp;
struct child_process cmd;
struct string_list_item *item;
struct argv_array cmd_args = ARGV_ARRAY_INIT;
struct string_list names = STRING_LIST_INIT_DUP;
- struct string_list rollback = STRING_LIST_INIT_DUP;
+ struct string_list rollback = STRING_LIST_INIT_NODUP;
struct string_list existing_packs = STRING_LIST_INIT_DUP;
struct strbuf line = STRBUF_INIT;
- int count_packs, ext, ret;
+ int nr_packs, ext, ret, failed;
FILE *out;
/* variables to be filled by option parsing */
@@ -173,11 +169,11 @@ int cmd_repack(int argc, const char **argv, const char *prefix)
argc = parse_options(argc, argv, prefix, builtin_repack_options,
git_repack_usage, 0);
- sigchain_push_common(remove_pack_on_signal);
-
packdir = mkpathdup("%s/pack", get_object_directory());
packtmp = mkpathdup("%s/.tmp-%d-pack", packdir, (int)getpid());
+ sigchain_push_common(remove_pack_on_signal);
+
argv_array_push(&cmd_args, "pack-objects");
argv_array_push(&cmd_args, "--keep-true-parents");
argv_array_push(&cmd_args, "--honor-pack-keep");
@@ -233,14 +229,14 @@ int cmd_repack(int argc, const char **argv, const char *prefix)
if (ret)
return ret;
- count_packs = 0;
+ nr_packs = 0;
out = xfdopen(cmd.out, "r");
while (strbuf_getline(&line, out, '\n') != EOF) {
if (line.len != 40)
die("repack: Expecting 40 character sha1 lines only from pack-objects.");
strbuf_addstr(&line, "");
string_list_append(&names, line.buf);
- count_packs++;
+ nr_packs++;
}
fclose(out);
ret = finish_command(&cmd);
@@ -248,10 +244,10 @@ int cmd_repack(int argc, const char **argv, const char *prefix)
return ret;
argv_array_clear(&cmd_args);
- if (!count_packs && !quiet)
+ if (!nr_packs && !quiet)
printf("Nothing new to pack.\n");
- int failed = 0;
+ failed = 0;
for_each_string_list_item(item, &names) {
for (ext = 0; ext < 2; ext++) {
char *fname, *fname_old;
@@ -262,7 +258,7 @@ int cmd_repack(int argc, const char **argv, const char *prefix)
continue;
}
- fname_old = mkpathdup("%s/old-%s%s", packdir,
+ fname_old = mkpath("%s/old-%s%s", packdir,
item->string, exts[ext]);
if (file_exists(fname_old))
unlink(fname_old);
@@ -271,15 +267,13 @@ int cmd_repack(int argc, const char **argv, const char *prefix)
failed = 1;
break;
}
- string_list_append_nodup(&rollback, fname);
- free(fname);
- free(fname_old);
+ string_list_append(&rollback, fname);
}
if (failed)
break;
}
if (failed) {
- struct string_list rollback_failure;
+ struct string_list rollback_failure = STRING_LIST_INIT_DUP;
for_each_string_list_item(item, &rollback) {
char *fname, *fname_old;
fname = mkpathdup("%s/%s", packdir, item->string);
@@ -289,7 +283,7 @@ int cmd_repack(int argc, const char **argv, const char *prefix)
free(fname);
}
- if (rollback.nr) {
+ if (rollback_failure.nr) {
int i;
fprintf(stderr,
"WARNING: Some packs in use have been renamed by\n"
@@ -299,10 +293,10 @@ int cmd_repack(int argc, const char **argv, const char *prefix)
"WARNING: attempt to rename them back to their\n"
"WARNING: original names also failed.\n"
"WARNING: Please rename them in %s manually:\n", packdir);
- for (i = 0; i < rollback.nr; i++)
+ for (i = 0; i < rollback_failure.nr; i++)
fprintf(stderr, "WARNING: old-%s -> %s\n",
- rollback.items[i].string,
- rollback.items[i].string);
+ rollback_failure.items[i].string,
+ rollback_failure.items[i].string);
}
exit(1);
}
--
1.8.4.rc3.1.gc1ebd90
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