fix a bug in ini write

gex/gex_settings.c

@@ -3,6 +3,8 @@
 //
 
 #define GEX_H // to allow including other headers
+
+#include <utils/payload_builder.h>
 #include "gex_settings.h"
 #include "gex_defines.h"
 #include "gex_internal.h"
@@ -18,15 +20,26 @@ uint32_t GEX_IniRead(GexClient *gex, char *buffer, uint32_t maxlen)
 
     uint32_t actuallyRead = GEX_BulkRead(GEX_SysUnit(gex), &br);
 
+    if (actuallyRead == maxlen) {
+        actuallyRead--; // lose last char in favor of terminator
+    }
+
+    buffer[actuallyRead] = 0; // terminate
     return actuallyRead;
 }
 
 bool GEX_IniWrite(GexClient *gex, const char *buffer)
 {
+    uint8_t buf[8];
+    PayloadBuilder pb = pb_start(buf, 8, NULL);
+    pb_u32(&pb, (uint32_t) strlen(buffer));
+
     GexBulk bw = (GexBulk){
             .buffer = (uint8_t *) buffer,
             .len = (uint32_t) strlen(buffer),
-            .req_cmd = MSG_INI_WRITE
+            .req_cmd = MSG_INI_WRITE,
+            .req_data = buf,
+            .req_len = (uint32_t) pb_length(&pb),
     };
 
     return GEX_BulkWrite(GEX_SysUnit(gex), &bw);

main.c

@@ -27,12 +27,18 @@ int main(void)
 	gex = GEX_Init("/dev/ttyACM0", 200);
 	if (!gex) exit(1);
 
+#if 0
 	// INI read example
-//	char buffer[2000];
+	char buffer[2000];
-//	uint32_t len = GEX_IniRead(gex, buffer, 2000);
+	uint32_t len = GEX_IniRead(gex, buffer, 2000);
-//	printf("%.*s", len, buffer);
+	printf("%s", buffer);
 
-    // DO example
+	GEX_IniWrite(gex, buffer);
+    printf("Written.\r\n");
+#endif
+
+#if 0
+    // DO example - there's a 10-LED bargraph connected to this unit
     GexUnit *bg = GEX_GetUnit(gex, "bargraph", "DO");
 
     struct DO_Set {
@@ -40,6 +46,8 @@ int main(void)
     } __attribute__((packed));
 
     struct DO_Set cmd_set;
+
+    // animation on the bargraph
     for (int i = 0; i < 100; i++) {
         int n = i%20;
         if(n>=10) n=10-(n-10);
@@ -51,6 +59,7 @@ int main(void)
     // all dark
     cmd_set.bits = 0x3FF;
     GEX_Send(bg, 0x00, (uint8_t *)&cmd_set, sizeof(cmd_set));
+#endif
 
 	GEX_DeInit(gex);
 	return 0;