Fixed bugs where incomplete packets with escapes were not decoded correctly. Added a help patch.

svn path=/trunk/externals/mrpeach/; revision=14183

2 files changed, 265 insertions, 202 deletions

diff --git a/slipdec/slipdec-help.pd b/slipdec/slipdec-help.pd
new file mode 100644
index 0000000..ff84873
--- /dev/null
+++ b/slipdec/slipdec-help.pd
@@ -0,0 +1,60 @@
+#N canvas 167 296 901 442 10;

+#X obj 388 325 print decoded;

+#X msg 319 159 192 192 192 192 192;

+#X floatatom 339 182 5 0 0 0 - - -;

+#X obj 382 238 cnv 15 60 30 empty empty empty 20 12 0 14 -4034 -66577

+0;

+#X text -57 298 The motivation behind SLIP is the need to determine

+the boundaries of a packet when it is received one byte at a time \,

+as with a serial channel. Bytes are integers between 0 and 255;

+#X msg 185 25 verbosity \$1;

+#X obj 185 6 tgl 15 0 empty empty empty 17 7 0 10 -262144 -1 -1 0 1

+;

+#X text -57 355 SLIP (RFC 1055) is a simple encoding that prefixes

+each packet with 192 \, and replaces 192s inside the packet with 219

+followed by 220 Any 219 will be replaced with 219 and 221 The packet

+ends with 192;

+#X text 443 160 Null packets are invisible;

+#X obj 427 274 print valid;

+#X text -57 193 Note that the SLIP specification limits the maximum

+packet size to 1006...;

+#X obj 388 245 slipdec;

+#X text -57 221 ...but a float argument to slipdec or slipenc will

+set another maximum packet size;

+#X msg 229 69 192 \, 1.33 \, 192;

+#X text 335 45 This should give 1 192;

+#X text 321 69 Only bytes are permitted;

+#X msg 275 115 192 219 5 6 7 192;

+#X msg 253 93 1 43 5 6 7 192;

+#X text 348 92 Missing 192 at start is OK;

+#X text -58 139 [slipdec];

+#X text 548 404 Author: Martin Peach \, 2010/10/01;

+#X msg 205 45 192 1 \, 219 \, 220 \, 192;

+#X msg 297 137 1 25 5 6 7;

+#X text -57 257 Input can be any combination of float and list of floats

+as long as they are integers on [0...255];

+#X text 385 115 Bad escapes are invalid;

+#X text 368 136 Unterminated input will be accumulated until end is

+received;

+#X text 636 368 See also:;

+#X obj 695 370 slipenc;

+#X text -58 153 Decodes bytes from SLIP to raw. Useful for receiving

+OSC via [comport].;

+#X text 427 290 Right outlet is one whenever a valid packet is output

+\, zero if packet could not be decoded (bad packets are not output).

+;

+#X text 389 341 Left outlet gives lists of decoded bytes whenever valid

+= 1;

+#X text 267 24 Verbosity might be useful if things don't seem to be

+working;

+#X connect 1 0 11 0;

+#X connect 2 0 11 0;

+#X connect 5 0 11 0;

+#X connect 6 0 5 0;

+#X connect 11 0 0 0;

+#X connect 11 1 9 0;

+#X connect 13 0 11 0;

+#X connect 16 0 11 0;

+#X connect 17 0 11 0;

+#X connect 21 0 11 0;

+#X connect 22 0 11 0;

diff --git a/slipdec/slipdec.c b/slipdec/slipdec.c
index e654b24..ce80cce 100644
--- a/slipdec/slipdec.c
+++ b/slipdec/slipdec.c
@@ -1,50 +1,49 @@
-/* slipdec.c 20100513 Martin Peach */

-/* decode a list of SLIP-encoded bytes */

-#include "m_pd.h" 

-

-/* -------------------------- slipdec -------------------------- */

-#ifndef _SLIPCODES

-/* SLIP special character codes */

-#define SLIP_END     0300 /* indicates end of packet */

-#define SLIP_ESC     0333 /* indicates byte stuffing */

-#define SLIP_ESC_END 0334 /* SLIP_ESC SLIP_ESC_END means SLIP_END data byte */

-#define SLIP_ESC_ESC 0335 /* SLIP_ESC SLIP_ESC_ESC means SLIP_ESC data byte */

-#define MAX_SLIP 1006 /* maximum SLIP packet size */

-#define _SLIPCODES

-#endif // _SLIPCODES

-

-static t_class *slipdec_class;

-

-typedef struct _slipdec

-{

-    t_object    x_obj;

-    t_outlet    *x_slipdec_out;

-    t_outlet    *x_status_out;

-    t_atom      *x_slip_buf;

-    t_int       x_slip_length;

+/* slipdec.c 20100513 Martin Peach */
+/* decode a list of SLIP-encoded bytes */
+#include "m_pd.h" 
+
+/* -------------------------- slipdec -------------------------- */
+#ifndef _SLIPCODES
+/* SLIP special character codes */
+#define SLIP_END     0300 /* decimal 192 indicates end of packet */
+#define SLIP_ESC     0333 /* decimal 219 indicates byte stuffing */
+#define SLIP_ESC_END 0334 /* decimal 220 SLIP_ESC_END means SLIP_END as data byte */
+#define SLIP_ESC_ESC 0335 /* decimal 221 SLIP_ESC_ESC means SLIP_ESC as data byte */
+#define MAX_SLIP 1006 /* maximum SLIP packet size */
+#define _SLIPCODES
+#endif /* _SLIPCODES */
+
+static t_class *slipdec_class;
+
+typedef struct _slipdec
+{
+    t_object    x_obj;
+    t_outlet    *x_slipdec_out;
+    t_outlet    *x_status_out;
+    t_atom      *x_slip_buf;
+    t_int       x_slip_length;
     t_int       x_slip_max_length;
-    t_int       x_packet_index;

-    t_int       x_valid_SLIP;

-    t_int       x_esced;

-    t_int       x_verbose;

-} t_slipdec;

-

-static void *slipdec_new(t_symbol *s, int argc, t_atom *argv);

+    t_int       x_valid_SLIP;
+    t_int       x_esced;
+    t_int       x_verbose;
+} t_slipdec;
+
+static void *slipdec_new(t_symbol *s, int argc, t_atom *argv);
 static void slipdec_dump(t_slipdec *x, int dosend);
-static void slipdec_list(t_slipdec *x, t_symbol *s, int ac, t_atom *av);

-static void slipdec_float(t_slipdec *x, t_float f);

-static void slipdec_verbosity(t_slipdec *x, t_float f);

-static void slipdec_free(t_slipdec *x);

-void slipdec_setup(void);

-

-static void *slipdec_new(t_symbol *s, int argc, t_atom *argv)

-{

-    int i;

+static void slipdec_list(t_slipdec *x, t_symbol *s, int ac, t_atom *av);
+static void slipdec_float(t_slipdec *x, t_float f);
+static void slipdec_verbosity(t_slipdec *x, t_float f);
+static void slipdec_free(t_slipdec *x);
+void slipdec_setup(void);
+
+static void *slipdec_new(t_symbol *s, int argc, t_atom *argv)
+{
+    int i;
     t_slipdec  *x = (t_slipdec *)pd_new(slipdec_class);
     
     if (x == NULL) return x;
     
-    x->x_slip_max_length = MAX_SLIP;// default unless a float argument is given

+    x->x_slip_max_length = MAX_SLIP;// default unless a float argument is given
     for (i = 0; i < argc; ++i)
     {
         if (argv[i].a_type == A_FLOAT)
@@ -55,177 +54,181 @@ static void *slipdec_new(t_symbol *s, int argc, t_atom *argv)
         }
     }
 
-    x->x_slip_buf = (t_atom *)getbytes(sizeof(t_atom)*x->x_slip_max_length);

-    if(x->x_slip_buf == NULL)

-    {

-        error("slipdec: unable to allocate %lu bytes for x_slip_buf", (long)sizeof(t_atom)*x->x_slip_max_length);

-        return NULL;

-    }

-    /* init the slip buf atoms to float type */

-    for (i = 0; i < x->x_slip_max_length; ++i) x->x_slip_buf[i].a_type = A_FLOAT;

-    x->x_slipdec_out = outlet_new(&x->x_obj, &s_list);

-    x->x_status_out = outlet_new(&x->x_obj, &s_anything);

-    x->x_packet_index = 0;

-    x->x_valid_SLIP = 1;

-    return (x);

-}

+    x->x_slip_buf = (t_atom *)getbytes(sizeof(t_atom)*x->x_slip_max_length);
+    if(x->x_slip_buf == NULL)
+    {
+        error("slipdec: unable to allocate %lu bytes for x_slip_buf", (long)sizeof(t_atom)*x->x_slip_max_length);
+        return NULL;
+    }
+    /* init the slip buf atoms to float type */
+    for (i = 0; i < x->x_slip_max_length; ++i) x->x_slip_buf[i].a_type = A_FLOAT;
+    x->x_slipdec_out = outlet_new(&x->x_obj, &s_list);
+    x->x_status_out = outlet_new(&x->x_obj, &s_anything);
+    x->x_valid_SLIP = 1;
+    return (x);
+}
 
 static void slipdec_dump(t_slipdec *x, int dosend)
-{

+{
+    outlet_float(x->x_status_out, x->x_valid_SLIP);
     if(dosend)
-    {

-        if ((0 != x->x_valid_SLIP) && (x->x_slip_length > 0)) 

-        outlet_list(x->x_slipdec_out, &s_list, x->x_slip_length, x->x_slip_buf);

-    }

-
-    x->x_slip_length = x->x_esced = x->x_packet_index = 0;

-    x->x_valid_SLIP = 1;

-}

-

-static void slipdec_list(t_slipdec *x, t_symbol *s, int ac, t_atom *av)

-{

-    /* SLIP decode a list of bytes */

-    float   f;

-    int     i = 0, c;

-
-    /* x_slip_length will be non-zero if an incomplete packet is in the buffer */

+    {
+        if ((0 != x->x_valid_SLIP) && (x->x_slip_length > 0)) 
+			outlet_list(x->x_slipdec_out, &s_list, x->x_slip_length, x->x_slip_buf);
+    }
+
+    x->x_slip_length = x->x_esced = 0;
+    x->x_valid_SLIP = 1;
+}
+
+static void slipdec_list(t_slipdec *x, t_symbol *s, int ac, t_atom *av)
+{
+    /* SLIP decode a list of bytes */
+    float   f;
+    int     i, c;
+
+    if (x->x_verbose) post ("slipdec_list: buffer length %d, esc = %d", x->x_slip_length, x->x_esced);
+    /* x_slip_length will be non-zero if an incomplete packet is in the buffer */
     if ((ac + x->x_slip_length) > x->x_slip_max_length)
     {
-        pd_error (x, "slipdec_list: input packet longer than %d", x->x_slip_max_length);

-        x->x_slip_length = x->x_esced = x->x_packet_index = 0;

+        pd_error (x, "slipdec_list: input packet longer than %d", x->x_slip_max_length);
+		x->x_valid_SLIP = 0; /* not valid SLIP */
+        slipdec_dump(x,0);// reset
         return;
-    }

-    /* for each byte in the packet, send the appropriate character sequence */

-    for(; ((i < ac) && (x->x_slip_length < x->x_slip_max_length)); ++i)

-    {

-        /* check each atom for byteness */

-        f = atom_getfloat(&av[i]);

-        c = (((int)f) & 0x0FF);

-        if (c != f)

-        {

-            /* abort, input list needs to be fixed before this is gonna wuk */

-            pd_error (x, "slipdec: input %d out of range [0..255]", f);

-            return;

-        }

-        if(SLIP_END == c)

-        {

-            if (x->x_verbose) post ("slipdec_list: SLIP_END packet index is %d", x->x_packet_index);

-            /* If it's the beginning of a packet, ignore it */

+    }
+    /* for each byte in the packet, send the appropriate character sequence */
+    for(i = 0; ((i < ac) && (x->x_slip_length < x->x_slip_max_length)); ++i)
+    {
+        /* check each atom for byteness */
+        f = atom_getfloat(&av[i]);
+        c = (((int)f) & 0x0FF);
+        if (c != f)
+        {
+            /* abort, input list needs to be fixed before this is gonna wuk */
+            pd_error (x, "slipdec: input %d out of range [0..255]", f);
+			x->x_valid_SLIP = 0; /* not valid SLIP */
+	        slipdec_dump(x,0);// reset
+            return;
+        }
+        if(SLIP_END == c)
+        {
+            if (x->x_verbose) post ("slipdec_list: SLIP_END at %d", x->x_slip_length);
+            /* If it's the beginning of a packet, ignore it */
             if (x->x_slip_length)
-            {

-                if (x->x_verbose) post ("slipdec_list: end of packet");

-                /* send the packet */

-                slipdec_dump(x, 1);

-            }

-            continue;

-        }

-        if (SLIP_ESC == c)

-        {

-            if (x->x_verbose) post ("slipdec_list: SLIP_ESC %f = %d", f, c);

-            x->x_esced = 1;

-            continue;

-        }

-        if (1 == x->x_esced)

-        {

-            if (SLIP_ESC_END == c) c = SLIP_END;

-            else if (SLIP_ESC_ESC == c) c = SLIP_ESC;

-            else x->x_valid_SLIP = 0; /* not valid SLIP */

-            if (x->x_verbose) post ("slipdec_list: ESCED %f = %d", f, c);

-            x->x_esced = 0;

-        }

-        /* Add the character to the list */

-        x->x_slip_buf[x->x_slip_length++].a_w.w_float = c;

-    }

-    if (0 != x->x_slip_length)

-    {

-        if(SLIP_END != c) x->x_valid_SLIP = 0;

-        outlet_float(x->x_status_out, x->x_valid_SLIP);

-        if (0 != x->x_valid_SLIP) outlet_list(x->x_slipdec_out, &s_list, x->x_slip_length, x->x_slip_buf);

-        x->x_slip_length = x->x_esced = x->x_packet_index = 0;

-        x->x_valid_SLIP = 1;

-        /* any remaining data in the list is ignored for now... */
-        if (i < ac-1) post("slipdec_list: dropped %d bytes after packet", ac-1-i);
-    }

-}

-

-static void slipdec_float(t_slipdec *x, t_float f)

-{

-    /* SLIP decode a byte */

-    int         c;

-    /* for each byte in the packet, send the appropriate character sequence */

-    /* check each atom for byteness */

-    c = (((int)f) & 0x0FF);

-    if (c != f)

-    {

-        /* abort, input list needs to be fixed before this is gonna wuk */

-        pd_error (x, "slipdec: input %d out of range [0..255]", f);

-        x->x_slip_length = x->x_esced = x->x_packet_index = 0;

-        x->x_valid_SLIP = 1;

-        return;

-    }

-    if(SLIP_END == c)

-    {

-        if (x->x_verbose) post ("slipdec_float: SLIP_END packet index is %d", x->x_packet_index);

-        /* If it's the beginning of a packet, ignore it */

-        if (0 == x->x_packet_index) return;

-        /* send the packet */

-        else

-        {

-            if (x->x_verbose) post ("slipdec_float: end of packet");

-            outlet_float(x->x_status_out, x->x_valid_SLIP);

-            if ((0 != x->x_slip_length) && (0 != x->x_valid_SLIP))

-                outlet_list(x->x_slipdec_out, &s_list, x->x_slip_length, x->x_slip_buf);

-            x->x_slip_length = x->x_esced = x->x_packet_index = 0;

-            x->x_valid_SLIP = 1;

-            return;

-        }

-    }

-    if (SLIP_ESC == c)

-    {

-        if (x->x_verbose) post ("slipdec_float: SLIP_ESC %f = %d", f, c);

-        x->x_esced = 1;

-        return;

-    }

-    if (1 == x->x_esced)

-    {

-        if (SLIP_ESC_END == c) c = SLIP_END;

-        else if (SLIP_ESC_ESC == c) c = SLIP_ESC;

-        else x->x_valid_SLIP = 0; /* not valid SLIP */

-        if (x->x_verbose) post ("slipdec_float: ESCED %f = %d", f, c);

-        x->x_esced = 0;

-    }

-    /* Add the character to the list */

-    if (0 == x->x_packet_index++) x->x_slip_length = 0;

+            {
+                if (x->x_verbose) post ("slipdec_list: end of packet");
+                /* send the packet */
+                slipdec_dump(x, 1);
+            }
+            continue;
+        }
+        if (SLIP_ESC == c)
+        {
+            if (x->x_verbose) post ("slipdec_list: SLIP_ESC %f = %d", f, c);
+            x->x_esced = 1;
+            continue;
+        }
+        if (1 == x->x_esced)
+        {
+            if (SLIP_ESC_END == c) c = SLIP_END;
+            else if (SLIP_ESC_ESC == c) c = SLIP_ESC;
+            else
+			{
+				pd_error (x, "slipdec_list: SLIP_ESC not followed by 220 or 221 (%d)", c);
+				x->x_valid_SLIP = 0; /* not valid SLIP */
+		        slipdec_dump(x,0);/* reset */
+				return;
+ 			}
+            x->x_esced = 0;
+        }
+        /* Add the character to the buffer */
+        if (x->x_verbose) post ("slipdec_list: adding character %d to buffer[%d]", c, x->x_slip_length);
+        x->x_slip_buf[x->x_slip_length++].a_w.w_float = c;
+    }
+}
+
+static void slipdec_float(t_slipdec *x, t_float f)
+{
+    /* SLIP decode a byte */
+    int         c;
+
+	if (x->x_verbose) post ("slipdec_float: buffer length %d, esc = %d", x->x_slip_length, x->x_esced);
+	/* for each byte in the packet, send the appropriate character sequence */
+    /* check each atom for byteness */
+    c = (((int)f) & 0x0FF);
+    if (c != f)
+    {
+        /* abort, input list needs to be fixed before this is gonna wuk */
+        pd_error (x, "slipdec: input %d out of range [0..255]", f);
+		x->x_valid_SLIP = 0; /* not valid SLIP */
+		slipdec_dump(x,0);/* reset */
+        return;
+    }
+    if(SLIP_END == c)
+    {
+        if (x->x_verbose) post ("slipdec_float: SLIP_END at %d", x->x_slip_length);
+        /* If it's the beginning of a packet, ignore it */
+        if (0 == x->x_slip_length) return;
+        /* send the packet */
+        else
+        {
+            if (x->x_verbose) post ("slipdec_float: end of packet");
+            slipdec_dump(x, 1);
+            return;
+        }
+    }
+    if (SLIP_ESC == c)
+    {
+        if (x->x_verbose) post ("slipdec_float: SLIP_ESC %f = %d", f, c);
+        x->x_esced = 1;
+        return;
+    }
+    if (1 == x->x_esced)
+    {
+        if (SLIP_ESC_END == c) c = SLIP_END;
+        else if (SLIP_ESC_ESC == c) c = SLIP_ESC;
+        else
+		{
+			x->x_valid_SLIP = 0; /* not valid SLIP */
+	        slipdec_dump(x,0);/* reset */
+			pd_error (x, "slipdec_float: SLIP_ESC not followed by 220 or 221 (%d)", c);
+			return;
+		}
+		if (x->x_verbose) post ("slipdec_float: ESCED %f = %d", f, c);
+        x->x_esced = 0;
+    }
+    /* Add the character to the buffer */
     if (x->x_slip_length < x->x_slip_max_length)
     {
+        if (x->x_verbose) post ("slipdec_float: adding character %d to buffer[%d]", c, x->x_slip_length);
         x->x_slip_buf[x->x_slip_length++].a_w.w_float = c;
     }
     else
     {
-        pd_error (x, "slipdec: input packet longer than %d", x->x_slip_length);

-        x->x_slip_length = x->x_esced = x->x_packet_index = 0;

-    }

-}

-

-static void slipdec_verbosity(t_slipdec *x, t_float f)

-{

-    x->x_verbose = (0 != f)?1:0;

-}

-

-static void slipdec_free(t_slipdec *x)

-{

-    if (x->x_slip_buf != NULL) freebytes((void *)x->x_slip_buf, sizeof(t_atom)*x->x_slip_max_length);

-}

-

-void slipdec_setup(void)

-{

-    slipdec_class = class_new(gensym("slipdec"), 

-        (t_newmethod)slipdec_new, (t_method)slipdec_free,

-        sizeof(t_slipdec), 0, A_GIMME, 0);

-    class_addlist(slipdec_class, slipdec_list);

-    class_addfloat(slipdec_class, slipdec_float);

-    class_addmethod(slipdec_class, (t_method)slipdec_verbosity, gensym("verbosity"), A_FLOAT, 0);

-    class_sethelpsymbol(slipdec_class, gensym("slipenc")); /* use slipenc-help.pd */

-}

-

-/* fin slipdec.c*/

+        pd_error (x, "slipdec: input packet longer than %d", x->x_slip_length);
+		x->x_valid_SLIP = 0; /* not valid SLIP */
+        slipdec_dump(x,0);/* reset */
+    }
+}
+
+static void slipdec_verbosity(t_slipdec *x, t_float f)
+{
+    x->x_verbose = (0 != f)?1:0;
+}
+
+static void slipdec_free(t_slipdec *x)
+{
+    if (x->x_slip_buf != NULL) freebytes((void *)x->x_slip_buf, sizeof(t_atom)*x->x_slip_max_length);
+}
+
+void slipdec_setup(void)
+{
+    slipdec_class = class_new(gensym("slipdec"), 
+        (t_newmethod)slipdec_new, (t_method)slipdec_free,
+        sizeof(t_slipdec), 0, A_GIMME, 0);
+    class_addlist(slipdec_class, slipdec_list);
+    class_addfloat(slipdec_class, slipdec_float);
+    class_addmethod(slipdec_class, (t_method)slipdec_verbosity, gensym("verbosity"), A_FLOAT, 0);
+}
+
+/* fin slipdec.c */