libdvbv5: simplify PMT table parser

Do a cleanup at the code, simplifying it, and removing
the second pointer for the linked list.

While here, add support for multisection PMT.

That makes the code easier to analyse and review.

Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

diff --git a/lib/libdvbv5/descriptors/pmt.c b/lib/libdvbv5/descriptors/pmt.c
index 714a582..308a910 100644 (file)
--- a/lib/libdvbv5/descriptors/pmt.c
+++ b/lib/libdvbv5/descriptors/pmt.c
@@ -25,40 +25,43 @@
 
 #include <string.h> /* memcpy */
 
-void dvb_table_pmt_init(struct dvb_v5_fe_parms *parms, const uint8_t *buf, ssize_t buflen, uint8_t *table, ssize_t *table_length)
+void dvb_table_pmt_init(struct dvb_v5_fe_parms *parms, const uint8_t *buf,
+                       ssize_t buflen, uint8_t *table, ssize_t *table_length)
 {
        const uint8_t *p = buf, *endbuf = buf + buflen - 4;
-       struct dvb_table_pmt *pmt = (struct dvb_table_pmt *) table;
-       struct dvb_table_pmt_stream *last = NULL, **head;
+       struct dvb_table_pmt *pmt = (void *)table;
+       struct dvb_table_pmt_stream **head = &pmt->stream;
        size_t size;
 
        if (*table_length > 0) {
-               dvb_logerr("multisecttion PMT table not implemented");
-               return;
-       }
-       size = offsetof(struct dvb_table_pmt, stream);
-       if (p + size > endbuf) {
-               dvb_logerr("PMT table was truncated. Need %zu bytes, but has only %zu.",
-                          size, buflen);
-               return;
-       }
-       memcpy(table, p, size);
-       p += size;
-       *table_length = sizeof(struct dvb_table_pmt);
+               /* find end of current list */
+               while (*head != NULL)
+                       head = &(*head)->next;
+       } else {
+               size = offsetof(struct dvb_table_pmt, stream);
+               if (p + size > endbuf) {
+                       dvb_logerr("PMT table was truncated. Need %zu bytes, but has only %zu.",
+                               size, buflen);
+                       return;
+               }
+               memcpy(table, p, size);
+               p += size;
+               *table_length = sizeof(struct dvb_table_pmt);
 
-       bswap16(pmt->bitfield);
-       bswap16(pmt->bitfield2);
-       pmt->stream = NULL;
+               bswap16(pmt->bitfield);
+               bswap16(pmt->bitfield2);
+               pmt->stream = NULL;
 
-       /* skip prog section */
-       p += pmt->prog_length;
+               /* skip prog section */
+               p += pmt->prog_length;
+       }
 
        /* get the stream entries */
-       head = &pmt->stream;
        size = offsetof(struct dvb_table_pmt_stream, descriptor);
        while (p + size <= endbuf) {
-               struct dvb_desc **head_desc;
-               struct dvb_table_pmt_stream *stream = malloc(sizeof(struct dvb_table_pmt_stream));
+               struct dvb_table_pmt_stream *stream;
+
+               stream = malloc(sizeof(struct dvb_table_pmt_stream));
 
                memcpy(stream, p, size);
                p += size;
@@ -68,17 +71,14 @@ void dvb_table_pmt_init(struct dvb_v5_fe_parms *parms, const uint8_t *buf, ssize
                stream->descriptor = NULL;
                stream->next = NULL;
 
-               if (!*head)
-                       *head = stream;
-               if (last)
-                       last->next = stream;
+               *head = stream;
+               head = &(*head)->next;
 
                /* get the descriptors for each program */
-               head_desc = &stream->descriptor;
-               dvb_parse_descriptors(parms, p, stream->section_length, head_desc);
+               dvb_parse_descriptors(parms, p, stream->section_length,
+                                     &stream->descriptor);
 
                p += stream->section_length;
-               last = stream;
        }
        if (endbuf - p)
                dvb_logerr("PAT table has %zu spurious bytes at the end.",