Let compression backend check the compression flags.
Closes #214.
diff --git a/lib/zip_algorithm_xz.c b/lib/zip_algorithm_xz.c
index 09d9f74..3f588af 100644
--- a/lib/zip_algorithm_xz.c
+++ b/lib/zip_algorithm_xz.c
@@ -107,11 +107,6 @@
allocate(bool compress, int compression_flags, zip_error_t *error, zip_uint16_t method) {
struct ctx *ctx;
- if (compression_flags < 0) {
- zip_error_set(error, ZIP_ER_INVAL, 0);
- return NULL;
- }
-
if ((ctx = (struct ctx *)malloc(sizeof(*ctx))) == NULL) {
zip_error_set(error, ZIP_ER_MEMORY, 0);
return NULL;
@@ -119,6 +114,9 @@
ctx->error = error;
ctx->compress = compress;
+ if (ctx->compression_flags < 0 || ctx->compression_flags > 9) {
+ ctx->compression_flags = 6; /* default value */
+ }
ctx->compression_flags = (zip_uint32_t)compression_flags;
ctx->compression_flags |= LZMA_PRESET_EXTREME;
ctx->end_of_input = false;
diff --git a/lib/zip_algorithm_zstd.c b/lib/zip_algorithm_zstd.c
index c27e9fb..a921f6e 100644
--- a/lib/zip_algorithm_zstd.c
+++ b/lib/zip_algorithm_zstd.c
@@ -60,7 +60,7 @@
struct ctx *ctx;
/* 0: let zstd choose */
- if (compression_flags < 0 || compression_flags > 9) {
+ if (compression_flags < ZSTD_minCLevel() || compression_flags > ZSTD_maxCLevel()) {
compression_flags = 0;
}
diff --git a/lib/zip_set_file_compression.c b/lib/zip_set_file_compression.c
index 511c7d5..166c0c7 100644
--- a/lib/zip_set_file_compression.c
+++ b/lib/zip_set_file_compression.c
@@ -40,7 +40,7 @@
zip_entry_t *e;
zip_int32_t old_method;
- if (idx >= za->nentry || flags > 9) {
+ if (idx >= za->nentry) {
zip_error_set(&za->error, ZIP_ER_INVAL, 0);
return -1;
}
diff --git a/man/zip_set_file_compression.mdoc b/man/zip_set_file_compression.mdoc
index 1e30417..03d8bf3 100644
--- a/man/zip_set_file_compression.mdoc
+++ b/man/zip_set_file_compression.mdoc
@@ -29,7 +29,7 @@
.\" OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
.\" IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
.\"
-.Dd April 2, 2020
+.Dd March 19, 2021
.Dt ZIP_SET_FILE_COMPRESSION 3
.Os
.Sh NAME
@@ -74,6 +74,14 @@
Deflate the file with the
.Xr zlib 3
algorithm and default options.
+.It Dv ZIP_CM_XZ
+Use the
+.Xr xz 1
+algorithm for compression
+.It Dv ZIP_CM_ZSTD
+Use the
+.Xr zstd 1
+algorithm for compression
.El
.Pp
.Em NOTE :
@@ -82,10 +90,23 @@
.Pp
The
.Ar comp_flags
-argument defines the compression level, 1 being fastest compression
-and 9 highest.
-Allowed values are 0 (which uses the default compression for the
-algorithm) and 1-9, other values are undefined.
+argument defines the compression level.
+This value is dependent on the compression algorithm.
+In general, lower numbers mean faster de/compression and higher
+numbers mean slower de/compression.
+For
+.Dv ZIP_CM_BZIP ,
+.Dv ZIP_CM_DEFLATE ,
+and
+.Dv ZIP_CM_XZ
+1 is the fastest compression and 9 the best, 0 chooses the default.
+For
+.Dv ZIP_CM_ZSTD
+the value go from
+.Xr ZSTD_minCLevel 3
+to
+.Xr ZSTD_maxCLevel 3 .
+.Pp
Further compression method specific flags might be added over time.
.Pp
The current compression method for a file in a zip archive can be
