Use compression flags when compressing.

Document bzip2.

Author: 0-wiz-0

lib/zip_close.c

@@ -389,8 +389,7 @@ add_data(zip_t *za, zip_source_t *src, zip_dirent_t *de, progress_state_t *progr
     }
 
     if (needs_compress) {
-	/* TODO: compression flags */
-	if ((src_tmp = zip_source_compress(za, src_final, de->comp_method, 0)) == NULL) {
+	if ((src_tmp = zip_source_compress(za, src_final, de->comp_method, de->compression_level)) == NULL) {
 	    zip_source_free(src_final);
 	    return -1;
 	}

lib/zip_dirent.c

@@ -296,6 +296,7 @@ _zip_dirent_init(zip_dirent_t *de)
     de->int_attrib = 0;
     de->ext_attrib = ZIP_EXT_ATTRIB_DEFAULT;
     de->offset = 0;
+    de->compression_level = 0;
     de->encryption_method = ZIP_EM_NONE;
     de->password = NULL;
 }

lib/zip_set_file_compression.c

@@ -41,7 +41,7 @@ zip_set_file_compression(zip_t *za, zip_uint64_t idx, zip_int32_t method, zip_ui
     zip_entry_t *e;
     zip_int32_t old_method;
 
-    if (idx >= za->nentry) {
+    if (idx >= za->nentry || flags > 9) {
 	zip_error_set(&za->error, ZIP_ER_INVAL, 0);
 	return -1;
     }
@@ -60,11 +60,15 @@ zip_set_file_compression(zip_t *za, zip_uint64_t idx, zip_int32_t method, zip_ui
 
     old_method = (e->orig == NULL ? ZIP_CM_DEFAULT : e->orig->comp_method);
 
-    /* TODO: revisit this when flags are supported, since they may require a recompression */
+    /* TODO: do we want to recompress if level is set? Only if it's
+     * different than what bit flags tell us, but those are not
+     * defined for all compression methods, or not directly mappable
+     * to levels */
 
     if (method == old_method) {
 	if (e->changes) {
 	    e->changes->changed &= ~ZIP_DIRENT_COMP_METHOD;
+	    e->changes->compression_level = 0;
 	    if (e->changes->changed == 0) {
 		_zip_dirent_free(e->changes);
 		e->changes = NULL;
@@ -80,6 +84,7 @@ zip_set_file_compression(zip_t *za, zip_uint64_t idx, zip_int32_t method, zip_ui
         }
 
         e->changes->comp_method = method;
+	e->changes->compression_level = (zip_uint16_t)flags;
         e->changes->changed |= ZIP_DIRENT_COMP_METHOD;
     }
 

lib/zipint.h

@@ -283,6 +283,7 @@ struct zip_dirent {
     zip_uint32_t ext_attrib;		/* (c)  external file attributes */
     zip_uint64_t offset;		/* (c)  offset of local header */
 
+    zip_uint16_t compression_level;	/*      level of compression to use (never valid in orig) */
     zip_uint16_t encryption_method;	/*      encryption method, computed from other fields */
     char *password;                     /*      file specific encryption password */
 };

man/zip_set_file_compression.mdoc

@@ -1,5 +1,5 @@
 .\" zip_set_file_compression.mdoc -- set compression method and its flags
-.\" Copyright (C) 2012-2016 Dieter Baron and Thomas Klausner
+.\" Copyright (C) 2012-2017 Dieter Baron and Thomas Klausner
 .\"
 .\" This file is part of libzip, a library to manipulate ZIP files.
 .\" The authors can be contacted at <libzip@nih.at>
@@ -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 May 1, 2012
+.Dd April 6, 2017
 .Dt ZIP_SET_FILE_COMPRESSION 3
 .Os
 .Sh NAME
@@ -63,21 +63,26 @@ default compression; currently the same as
 .Dv ZIP_CM_DEFLATE .
 .It Dv ZIP_CM_STORE
 Store the file uncompressed.
+.It Dv ZIP_CM_BZIP2
+Compress the file using the
+.Xr bzip2 1
+algorithm.
 .It Dv ZIP_CM_DEFLATE
 Deflate the file with the
 .Xr zlib 3
 algorithm and default options
 .El
 .Pp
+.Em NOTE :
+Only the deflate and store methods can be assumed to be universally
+supported.
+.Pp
 The
 .Ar comp_flags
-argument is currently ignored.
-.\" For the comp_flags argument, the lower 4 bits define the compression
-.\" level.
-.\" 0 is fastest compression, 15 is highest compression
-.\" .Dv ZIP_COMP_FL_DEFAULT
-.\" can be used to specify that the default shall be used.
-.\" Further compression method specific flags will be added over time.
+argument defines the compression level, 1 being fastest compression
+and 9 highest.
+Allowed values are 1-9, other values are undefined.
+Further compression method specific flags might be added over time.
 .Pp
 The current compression method for a file in a zip archive can be
 determined using