erts: Add {line_delimiter, byte()} option to inet:setopts/2

A new {line_delimiter, byte()} option allows line-oriented TCP-based
protocols to use a custom line delimiting character. It is to be
used in conjunction with {packet, line}.

This option also works with erlang:decode_packet/3 when its first argument
is 'line'.

4 files changed, 14 insertions, 5 deletions

diff --git a/erts/emulator/beam/atom.names b/erts/emulator/beam/atom.names
index f9a2f3e33e..190e7817dc 100644
--- a/erts/emulator/beam/atom.names
+++ b/erts/emulator/beam/atom.names
@@ -321,6 +321,7 @@ atom ldflags
 atom Le='=<'
 atom lf
 atom line
+atom line_delimiter
 atom line_length
 atom linked_in_driver
 atom links
diff --git a/erts/emulator/beam/erl_bif_port.c b/erts/emulator/beam/erl_bif_port.c
index 3ff54c7a60..e47d7bcbbb 100644
--- a/erts/emulator/beam/erl_bif_port.c
+++ b/erts/emulator/beam/erl_bif_port.c
@@ -1329,7 +1329,8 @@ BIF_RETTYPE decode_packet_3(BIF_ALIST_3)
     ErlSubBin* rest;
     Eterm res;
     Eterm options;
-    int code;
+    int   code;
+    char  delimiter = '\n';
 
     if (!is_binary(BIF_ARG_2) || 
         (!is_list(BIF_ARG_3) && !is_nil(BIF_ARG_3))) {
@@ -1370,6 +1371,11 @@ BIF_RETTYPE decode_packet_3(BIF_ALIST_3)
                 case am_line_length:
                     trunc_len = val;
                     goto next_option;
+                case am_line_delimiter:
+                    if (type == TCP_PB_LINE_LF && val >= 0 && val <= 255) {
+                        delimiter = (char)val;
+                        goto next_option;
+                    }
                 }
             }
         }
@@ -1390,7 +1396,7 @@ BIF_RETTYPE decode_packet_3(BIF_ALIST_3)
         pca.aligned_ptr = bin_ptr;
     }
     packet_sz = packet_get_length(type, (char*)pca.aligned_ptr, pca.bin_sz,
-                                  max_plen, trunc_len, &http_state);
+                                  max_plen, trunc_len, delimiter, &http_state);
     if (!(packet_sz > 0 && packet_sz <= pca.bin_sz)) {
         if (packet_sz < 0) {
 	    goto error;
diff --git a/erts/emulator/beam/packet_parser.c b/erts/emulator/beam/packet_parser.c
index 2dd421a9e9..a737a86f14 100644
--- a/erts/emulator/beam/packet_parser.c
+++ b/erts/emulator/beam/packet_parser.c
@@ -256,6 +256,7 @@ int packet_get_length(enum PacketParseType htype,
                       const char* ptr, unsigned n, /* Bytes read so far */
                       unsigned max_plen,     /* Max packet length, 0=no limit */
                       unsigned trunc_len,    /* Truncate (lines) if longer, 0=no limit */
+                      char     delimiter,    /* Line delimiting character */
                       int*     statep)       /* Protocol specific state */
 {
     unsigned hlen, plen;
@@ -299,9 +300,9 @@ int packet_get_length(enum PacketParseType htype,
         goto remain;
 
     case TCP_PB_LINE_LF: {
-        /* TCP_PB_LINE_LF:  [Data ... \n]  */
+        /* TCP_PB_LINE_LF:  [Data ... Delimiter]  */
         const char* ptr2;
-        if ((ptr2 = memchr(ptr, '\n', n)) == NULL) {
+        if ((ptr2 = memchr(ptr, delimiter, n)) == NULL) {
             if (n > max_plen && max_plen != 0) { /* packet full */
                 DEBUGF((" => packet full (no NL)=%d\r\n", n));
                 goto error;
diff --git a/erts/emulator/beam/packet_parser.h b/erts/emulator/beam/packet_parser.h
index ff158ff8b8..717d905fad 100644
--- a/erts/emulator/beam/packet_parser.h
+++ b/erts/emulator/beam/packet_parser.h
@@ -105,7 +105,8 @@ int packet_get_length(enum PacketParseType htype,
 		      const char* ptr, unsigned n,  /* Bytes read so far */
 		      unsigned max_plen,      /* Packet max length, 0=no limit */
 		      unsigned trunc_len,     /* Truncate (lines) if longer, 0=no limit */
-		      int* statep);           /* Internal protocol state */
+		      char     delimiter,     /* Line delimiting character */
+		      int*     statep);       /* Internal protocol state */
 
 ERTS_GLB_INLINE
 void packet_get_body(enum PacketParseType htype,