Add utility to extract SMS concatenation info

diff --git a/src/smsutil.c b/src/smsutil.c
index a244e58..ff7d106 100644 (file)
--- a/src/smsutil.c
+++ b/src/smsutil.c
@@ -1775,3 +1775,89 @@ gboolean sms_extract_app_port(const struct sms *sms, int *dst, int *src)
 
        return TRUE;
 }
+
+gboolean sms_extract_concatenation(const struct sms *sms, int *ref_num,
+                                       int *max_msgs, int *seq_num)
+{
+       struct sms_udh_iter iter;
+       enum sms_iei iei;
+       guint8 concat_hdr[4];
+       int rn, max, seq;
+       gboolean concatenated = FALSE;
+
+       /* We must ignore the entire user_data header here:
+        * If the length of the User Data Header is such that there
+        * are too few or too many octets in the final Information
+        * Element then the whole User Data Header shall be ignored.
+        */
+       if (!sms_udh_iter_init(sms, &iter))
+               return FALSE;
+
+       /* According to the specification, we have to use the last
+        * useable header:
+        * In the event that IEs determined as not repeatable are
+        * duplicated, the last occurrence of the IE shall be used.
+        * In the event that two or more IEs occur which have mutually
+        * exclusive meanings (e.g. an 8bit port address and a 16bit
+        * port address), then the last occurring IE shall be used.
+        */
+       while ((iei = sms_udh_iter_get_ie_type(&iter)) !=
+                       SMS_IEI_INVALID) {
+               switch (iei) {
+               case SMS_IEI_CONCATENATED_8BIT:
+                       if (sms_udh_iter_get_ie_length(&iter) != 3)
+                               break;
+
+                       sms_udh_iter_get_ie_data(&iter, concat_hdr);
+
+                       if (concat_hdr[1] == 0)
+                               break;
+
+                       if (concat_hdr[2] == 0 || concat_hdr[1] > concat_hdr[2])
+                               break;
+
+                       rn = concat_hdr[0];
+                       max = concat_hdr[1];
+                       seq = concat_hdr[2];
+                       concatenated = TRUE;
+                       break;
+
+               case SMS_IEI_CONCATENATED_16BIT:
+                       if (sms_udh_iter_get_ie_length(&iter) != 4)
+                               break;
+
+                       sms_udh_iter_get_ie_data(&iter, concat_hdr);
+
+                       if (concat_hdr[2] == 0)
+                               break;
+
+                       if (concat_hdr[3] == 0 ||
+                                       concat_hdr[2] > concat_hdr[3])
+                               break;
+
+                       rn = (concat_hdr[0] << 8) | concat_hdr[1];
+                       max = concat_hdr[2];
+                       seq = concat_hdr[3];
+                       concatenated = TRUE;
+                       break;
+               default:
+                       break;
+               }
+
+               sms_udh_iter_next(&iter);
+       }
+
+       if (!concatenated)
+               return FALSE;
+
+       if (ref_num)
+               *ref_num = rn;
+
+       if (max_msgs)
+               *max_msgs = max;
+
+       if (seq_num)
+               *seq_num = seq;
+
+       return TRUE;
+}

diff --git a/src/smsutil.h b/src/smsutil.h
index a2fc063..9b67977 100644 (file)
--- a/src/smsutil.h
+++ b/src/smsutil.h
@@ -354,4 +354,6 @@ gboolean sms_mwi_dcs_decode(guint8 dcs, enum sms_mwi_type *type,
                                gboolean *active, gboolean *discard);
 
 gboolean sms_extract_app_port(const struct sms *sms, int *dst, int *src);
+gboolean sms_extract_concatenation(const struct sms *sms, int *ref_num,
+                                       int *max_msgs, int *seq_num);
 #endif