From 52f5717ff34c5880d7600231df6f0f8e2232c6f4 Mon Sep 17 00:00:00 2001
From: Ian Jackson <ian@liberator.(none)>
Date: Fri, 2 Oct 2009 21:47:33 +0100
Subject: [PATCH 1/1] WIP routesearch: trade value; before separate query for
 qties

---
 yarrg/rssetup.c | 3 ++-
 yarrg/rsvalue.c | 5 +++++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/yarrg/rssetup.c b/yarrg/rssetup.c
index 88b6fc6..dadeca6 100644
--- a/yarrg/rssetup.c
+++ b/yarrg/rssetup.c
@@ -48,7 +48,8 @@ int sql_step_wrap(sqlite3_stmt *ssh, const char *ssh_string,
 	fprintf(stderr,"SQL %s R",ssh_string);
 	for (i=0; i<sqlite3_column_count(ssh); i++) {
 	  fputc('\t',stderr);
-	  fputs((char*)sqlite3_column_text(ssh,i),stderr);
+	  const char *txt= (const char*)sqlite3_column_text(ssh,i);
+	  fputs(txt ? txt : "<null>", stderr);
 	}
 	fputs("\n",stderr);
       }
diff --git a/yarrg/rsvalue.c b/yarrg/rsvalue.c
index 9cc9ec7..ad301b0 100644
--- a/yarrg/rsvalue.c
+++ b/yarrg/rsvalue.c
@@ -108,6 +108,7 @@ static int setup_leg_constraints(double max_thing, int legs, const char *wh) {
 
 static void add_leg_c(int startrow, int leg, double value) {
   if (startrow<=0) return;
+  assert(value > 0);
   add_constraint(startrow+leg, value);
 }
 
@@ -243,6 +244,7 @@ void value_route(int nislands, const int *islands) {
 	if (islands[already_d] == di)
 	  /* visited this island already since we left s, uninteresting */
 	  goto next_d;
+
       if (d>s && di==si)
 	/* route has returned to si, no need to think more about s */
 	goto next_s;
@@ -252,6 +254,9 @@ void value_route(int nislands, const int *islands) {
       IslandPair *ip= ipair_get(islands[s], islands[d]);
       TradesBlock *block= ip->trades;
       int tradestodo= ip->ntrades;
+      if (!tradestodo)
+	goto next_d;
+
       int inblock= 0;
       int col= lpx_add_cols(lp,ip->ntrades);
 
-- 
2.30.2