libsmartcols: resuse buffer for encoded data

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/libsmartcols/src/table_print.c b/libsmartcols/src/table_print.c
index 91cff930f09c67a8e9cd7cb117430ebf91c277e7..c64fe108edd7f33b99f44a1e07f4f7bb89aa0325 100644 (file)
--- a/libsmartcols/src/table_print.c
+++ b/libsmartcols/src/table_print.c
@@ -32,6 +32,7 @@
 struct libscols_buffer {
        char    *begin;         /* begin of the buffer */
        char    *cur;           /* current end of  the buffer */
+       char    *encdata;       /* encoded buffer mbs_safe_encode() */
 
        size_t  bufsz;          /* size of the buffer */
 };
@@ -44,12 +45,14 @@ static struct libscols_buffer *new_buffer(size_t sz)
                return NULL;
 
        buf->cur = buf->begin = ((char *) buf) + sizeof(struct libscols_buffer);
+       buf->encdata = NULL;
        buf->bufsz = sz;
        return buf;
 }
 
 static void free_buffer(struct libscols_buffer *buf)
 {
+       free(buf->encdata);
        free(buf);
 }
 
@@ -94,6 +97,30 @@ static char *buffer_get_data(struct libscols_buffer *buf)
        return buf ? buf->begin : NULL;
 }
 
+static char *buffer_get_safe_data(struct libscols_buffer *buf, size_t *cells)
+{
+       char *data = buffer_get_data(buf);
+       char *res = NULL;
+
+       if (!data)
+               goto nothing;
+
+       if (!buf->encdata) {
+               buf->encdata = malloc(mbs_safe_encode_size(buf->bufsz) + 1);
+               if (!buf->encdata)
+                       goto nothing;
+       }
+
+       res = mbs_safe_encode_to_buffer(data, cells, buf->encdata);
+       if (!res || !*cells || *cells == (size_t) -1)
+               goto nothing;
+
+       return res;
+nothing:
+       *cells = 0;
+       return NULL;
+}
+
 #define is_last_column(_tb, _cl) \
                list_entry_is_last(&(_cl)->cl_columns, &(_tb)->tb_columns)
 
@@ -108,7 +135,7 @@ static int print_data(struct libscols_table *tb,
 {
        size_t len = 0, i, width;
        const char *color = NULL;
-       char *data, *data_enc = NULL;
+       char *data;
 
        assert(tb);
        assert(cl);
@@ -143,15 +170,10 @@ static int print_data(struct libscols_table *tb,
                        color = cl->color;
        }
 
-       /* note that 'len' and 'width' are number of cells, not bytes */
-       data_enc = data = mbs_safe_encode(data, &len);
+       /* encode, note that 'len' and 'width' are number of cells, not bytes */
+       data = buffer_get_safe_data(buf, &len);
        if (!data)
                data = "";
-
-       if (!len || len == (size_t) -1) {
-               len = 0;
-               data = NULL;
-       }
        width = cl->width;
 
        if (is_last_column(tb, cl) && len < width && !scols_table_is_maxout(tb))
@@ -199,7 +221,6 @@ static int print_data(struct libscols_table *tb,
                        fputs(colsep(tb), tb->out);     /* columns separator */
        }
 
-       free(data_enc);
        return 0;
 }