Compression programs like zip, gzip, bzip2 and xz allow to adjust the
trade-off between CPU cost and size gain with numerical options from -1
for fast compression and -9 for high compression ratio. zip also
accepts -0 for storing files verbatim. git archive directly support
these single-digit compression levels for ZIP output and passes them to
filters like gzip.
Zstandard additionally supports compression level options -10 to -19, or
up to -22 with --ultra. This *seems* to work with git archive in most
cases, e.g. it will produce an archive with -19 without complaining, but
since it only supports single-digit compression level options this is
the same as -1 -9 and thus -9.
Allow git archive to accept multi-digit compression levels to support
the full range supported by zstd. Explicitly reject them for the ZIP
format, as otherwise deflateInit2() would just fail with a somewhat
cryptic "stream consistency error".
Signed-off-by: René Scharfe <l.s.r@xxxxxx>
---
archive-tar.c | 3 ++-
archive.c | 26 +++++++++++---------------
archive.h | 1 +
3 files changed, 14 insertions(+), 16 deletions(-)
diff --git a/archive-tar.c b/archive-tar.c
index f1a1447ebd..a971fdc0f6 100644
--- a/archive-tar.c
+++ b/archive-tar.c
@@ -374,7 +374,8 @@ static int tar_filter_config(const char *var, const char *value, void *data)
ar = xcalloc(1, sizeof(*ar));
ar->name = xmemdupz(name, namelen);
ar->write_archive = write_tar_filter_archive;
- ar->flags = ARCHIVER_WANT_COMPRESSION_LEVELS;
+ ar->flags = ARCHIVER_WANT_COMPRESSION_LEVELS |
+ ARCHIVER_HIGH_COMPRESSION_LEVELS;
ALLOC_GROW(tar_filters, nr_tar_filters + 1, alloc_tar_filters);
tar_filters[nr_tar_filters++] = ar;
}
diff --git a/archive.c b/archive.c
index 3c1541af9e..7a888c5338 100644
--- a/archive.c
+++ b/archive.c
@@ -529,10 +529,12 @@ static int add_file_cb(const struct option *opt, const char *arg, int unset)
return 0;
}
-#define OPT__COMPR(s, v, h, p) \
- OPT_SET_INT_F(s, NULL, v, h, p, PARSE_OPT_NONEG)
-#define OPT__COMPR_HIDDEN(s, v, p) \
- OPT_SET_INT_F(s, NULL, v, "", p, PARSE_OPT_NONEG | PARSE_OPT_HIDDEN)
+static int number_callback(const struct option *opt, const char *arg, int unset)
+{
+ BUG_ON_OPT_NEG(unset);
+ *(int *)opt->value = strtol(arg, NULL, 10);
+ return 0;
+}
static int parse_archive_args(int argc, const char **argv,
const struct archiver **ar, struct archiver_args *args,
@@ -561,16 +563,8 @@ static int parse_archive_args(int argc, const char **argv,
OPT_BOOL(0, "worktree-attributes", &worktree_attributes,
N_("read .gitattributes in working directory")),
OPT__VERBOSE(&verbose, N_("report archived files on stderr")),
- OPT__COMPR('0', &compression_level, N_("store only"), 0),
- OPT__COMPR('1', &compression_level, N_("compress faster"), 1),
- OPT__COMPR_HIDDEN('2', &compression_level, 2),
- OPT__COMPR_HIDDEN('3', &compression_level, 3),
- OPT__COMPR_HIDDEN('4', &compression_level, 4),
- OPT__COMPR_HIDDEN('5', &compression_level, 5),
- OPT__COMPR_HIDDEN('6', &compression_level, 6),
- OPT__COMPR_HIDDEN('7', &compression_level, 7),
- OPT__COMPR_HIDDEN('8', &compression_level, 8),
- OPT__COMPR('9', &compression_level, N_("compress better"), 9),
+ OPT_NUMBER_CALLBACK(&compression_level,
+ N_("set compression level"), number_callback),
OPT_GROUP(""),
OPT_BOOL('l', "list", &list,
N_("list supported archive formats")),
@@ -617,7 +611,9 @@ static int parse_archive_args(int argc, const char **argv,
args->compression_level = Z_DEFAULT_COMPRESSION;
if (compression_level != -1) {
- if ((*ar)->flags & ARCHIVER_WANT_COMPRESSION_LEVELS)
+ int levels_ok = (*ar)->flags & ARCHIVER_WANT_COMPRESSION_LEVELS;
+ int high_ok = (*ar)->flags & ARCHIVER_HIGH_COMPRESSION_LEVELS;
+ if (levels_ok && (compression_level <= 9 || high_ok))
args->compression_level = compression_level;
else {
die(_("Argument not supported for format '%s': -%d"),
diff --git a/archive.h b/archive.h
index 82b226011a..e3d04e8ab3 100644
--- a/archive.h
+++ b/archive.h
@@ -36,6 +36,7 @@ const char *archive_format_from_filename(const char *filename);
#define ARCHIVER_WANT_COMPRESSION_LEVELS 1
#define ARCHIVER_REMOTE 2
+#define ARCHIVER_HIGH_COMPRESSION_LEVELS 4
struct archiver {
const char *name;
int (*write_archive)(const struct archiver *, struct archiver_args *);
--
2.29.2
