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authoretobi <git@e-tobi.net>2013-09-03 09:48:41 +0200
committeretobi <git@e-tobi.net>2013-09-03 09:48:41 +0200
commitab959d7b4194715870128e616b8e29d4a101e488 (patch)
tree61a746231d30817be73416a7d67763fd677a1042 /lib/libucsi/section_buf.c
parent6b350466c4902c5b137e0efaf1d189128a7f18f5 (diff)
downloadlinux-dvb-apps-ab959d7b4194715870128e616b8e29d4a101e488.tar.gz
Imported Upstream version 1.1.1+rev1207upstream/1.1.1+rev1207
Diffstat (limited to 'lib/libucsi/section_buf.c')
-rw-r--r--lib/libucsi/section_buf.c173
1 files changed, 173 insertions, 0 deletions
diff --git a/lib/libucsi/section_buf.c b/lib/libucsi/section_buf.c
new file mode 100644
index 0000000..35d465e
--- /dev/null
+++ b/lib/libucsi/section_buf.c
@@ -0,0 +1,173 @@
+/*
+ * section and descriptor parser
+ *
+ * Copyright (C) 2005 Andrew de Quincey (adq_dvb@lidskialf.net)
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
+ */
+
+#include <errno.h>
+#include <string.h>
+#include "section_buf.h"
+
+#define SECTION_HDR_SIZE 3
+#define SECTION_PAD 0xff
+
+int section_buf_init(struct section_buf *section, int max)
+{
+ if (max < SECTION_HDR_SIZE)
+ return -EINVAL;
+
+ memset(section, 0, sizeof(struct section_buf));
+ section->max = max; /* max size of data */
+ section->len = SECTION_HDR_SIZE;
+ section->wait_pdu = 1;
+
+ return 0;
+}
+
+int section_buf_add(struct section_buf *section, uint8_t* frag, int len, int *section_status)
+{
+ int copy;
+ int used = 0;
+ uint8_t *data;
+ uint8_t *pos = (uint8_t*) section + sizeof(struct section_buf) + section->count;
+
+ /* have we finished? */
+ if (section->header && (section->len == section->count)) {
+ *section_status = 1;
+ return 0;
+ }
+
+ /* skip over section padding bytes */
+ *section_status = 0;
+ if (section->count == 0) {
+ while(len && (*frag == SECTION_PAD)) {
+ frag++;
+ len--;
+ used++;
+ }
+
+ if (len == 0)
+ return used;
+ }
+
+ /* grab the header to get the section length */
+ if (!section->header) {
+ /* copy the header frag */
+ copy = SECTION_HDR_SIZE - section->count;
+ if (copy > len)
+ copy = len;
+ memcpy(pos, frag, copy);
+ section->count += copy;
+ pos += copy;
+ frag += copy;
+ used += copy;
+ len -= copy;
+
+ /* we need 3 bytes for the section header */
+ if (section->count != SECTION_HDR_SIZE)
+ return used;
+
+ /* work out the length & check it isn't too big */
+ data = (uint8_t*) section + sizeof(struct section_buf);
+ section->len = SECTION_HDR_SIZE + (((data[1] & 0x0f) << 8) | data[2]);
+ if (section->len > section->max) {
+ *section_status = -ERANGE;
+ return len + used;
+ }
+
+ /* update fields */
+ section->header = 1;
+ }
+
+ /* accumulate frag */
+ copy = section->len - section->count;
+ if (copy > len)
+ copy = len;
+ memcpy(pos, frag, copy);
+ section->count += copy;
+ used += copy;
+
+ /* have we finished? */
+ if (section->header && (section->len == section->count))
+ *section_status = 1;
+
+ /* return number of bytes used */
+ return used;
+}
+
+int section_buf_add_transport_payload(struct section_buf *section,
+ uint8_t* payload, int len,
+ int pdu_start, int *section_status)
+{
+ int used = 0;
+ int tmp;
+
+ /* have we finished? */
+ if (section->header && (section->len == section->count)) {
+ *section_status = 1;
+ return 0;
+ }
+
+ /* don't bother if we're waiting for a PDU */
+ *section_status = 0;
+ if (section->wait_pdu && (!pdu_start))
+ return len;
+
+ /* if we're at a PDU start, we need extra handling for the extra first
+ * byte giving the offset to the start of the next section. */
+ if (pdu_start) {
+ /* we have received a pdu */
+ section->wait_pdu = 0;
+
+ /* work out the offset to the _next_ payload */
+ int offset = payload[0];
+ if ((offset+1) > len) {
+ section->wait_pdu = 1;
+ *section_status = -EINVAL;
+ return len;
+ }
+
+ /* accumulate the end if we need to */
+ if (section->count != 0) {
+ /* add the final fragment. */
+ tmp = section_buf_add(section, payload + 1, offset, section_status);
+
+ /* the stream said this was the final fragment
+ * (PDU START bit) - check that it really was! */
+ if ((tmp != offset) || section_buf_remaining(section) || (*section_status != 1)) {
+ *section_status = -ERANGE;
+ section->wait_pdu = 1;
+ return 1 + tmp;
+ }
+
+ /* it is complete - return the number of bytes we used */
+ return 1 + tmp;
+ }
+
+ /* otherwise, we skip the end of the previous section, and
+ * start accumulating the new data. */
+ used = 1 + offset;
+ }
+
+ /* ok, just accumulate the data as normal */
+ tmp = section_buf_add(section, payload+used, len - used, section_status);
+ if (*section_status < 0) {
+ section->wait_pdu = 1;
+ }
+
+ return used + tmp;
+}