1 files changed, 152 insertions, 0 deletions
diff --git a/libsmartcols/src/buffer.c b/libsmartcols/src/buffer.c
new file mode 100644
index 0000000..d376e8f
--- /dev/null
+++ b/libsmartcols/src/buffer.c
@@ -0,0 +1,152 @@
+
+#include "smartcolsP.h"
+#include "mbsalign.h"
+
+/* This is private struct to work with output data */
+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 */
+	size_t	art_idx;	/* begin of the tree ascii art or zero */
+};
+
+struct libscols_buffer *new_buffer(size_t sz)
+{
+	struct libscols_buffer *buf = malloc(sz + sizeof(struct libscols_buffer));
+
+	if (!buf)
+		return NULL;
+
+	buf->cur = buf->begin = ((char *) buf) + sizeof(struct libscols_buffer);
+	buf->encdata = NULL;
+	buf->bufsz = sz;
+
+	DBG(BUFF, ul_debugobj(buf, "alloc (size=%zu)", sz));
+	return buf;
+}
+
+void free_buffer(struct libscols_buffer *buf)
+{
+	if (!buf)
+		return;
+	DBG(BUFF, ul_debugobj(buf, "dealloc"));
+	free(buf->encdata);
+	free(buf);
+}
+
+int buffer_reset_data(struct libscols_buffer *buf)
+{
+	if (!buf)
+		return -EINVAL;
+
+	/*DBG(BUFF, ul_debugobj(buf, "reset data"));*/
+	buf->begin[0] = '\0';
+	buf->cur = buf->begin;
+	buf->art_idx = 0;
+	return 0;
+}
+
+int buffer_append_data(struct libscols_buffer *buf, const char *str)
+{
+	size_t maxsz, sz;
+
+	if (!buf)
+		return -EINVAL;
+	if (!str || !*str)
+		return 0;
+
+	sz = strlen(str);
+	maxsz = buf->bufsz - (buf->cur - buf->begin);
+
+	if (maxsz <= sz)
+		return -EINVAL;
+	memcpy(buf->cur, str, sz + 1);
+	buf->cur += sz;
+	return 0;
+}
+
+int buffer_append_ntimes(struct libscols_buffer *buf, size_t n, const char *str)
+{
+	size_t i;
+
+	for (i = 0; i < n; i++) {
+		int rc = buffer_append_data(buf, str);
+		if (rc)
+			return rc;
+	}
+	return 0;
+}
+
+int buffer_set_data(struct libscols_buffer *buf, const char *str)
+{
+	int rc = buffer_reset_data(buf);
+	return rc ? rc : buffer_append_data(buf, str);
+}
+
+/* save the current buffer position to art_idx */
+void buffer_set_art_index(struct libscols_buffer *buf)
+{
+	if (buf) {
+		buf->art_idx = buf->cur - buf->begin;
+		/*DBG(BUFF, ul_debugobj(buf, "art index: %zu", buf->art_idx));*/
+	}
+}
+
+char *buffer_get_data(struct libscols_buffer *buf)
+{
+	return buf ? buf->begin : NULL;
+}
+
+size_t buffer_get_size(struct libscols_buffer *buf)
+{
+	return buf ? buf->bufsz : 0;
+}
+
+/* encode data by mbs_safe_encode() to avoid control and non-printable chars */
+char *buffer_get_safe_data(struct libscols_table *tb,
+				  struct libscols_buffer *buf,
+				  size_t *cells,
+				  const char *safechars)
+{
+	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;
+	}
+
+	if (scols_table_is_noencoding(tb)) {
+		*cells = mbs_width(data);
+		strcpy(buf->encdata, data);
+		res = buf->encdata;
+	} else {
+		res = mbs_safe_encode_to_buffer(data, cells, buf->encdata, safechars);
+	}
+
+	if (!res || !*cells || *cells == (size_t) -1)
+		goto nothing;
+	return res;
+nothing:
+	*cells = 0;
+	return NULL;
+}
+
+/* returns size in bytes of the ascii art (according to art_idx) in safe encoding */
+size_t buffer_get_safe_art_size(struct libscols_buffer *buf)
+{
+	char *data = buffer_get_data(buf);
+	size_t bytes = 0;
+
+	if (!data || !buf->art_idx)
+		return 0;
+
+	mbs_safe_nwidth(data, buf->art_idx, &bytes);
+	return bytes;
+}