From 17e2feff261f35d7cada59f75f3c11840a1c4cdf Mon Sep 17 00:00:00 2001
From: Stefan Rueger <stefan.rueger@urclocks.com>
Date: Sun, 1 Jan 2023 23:29:06 +0000
Subject: [PATCH] Fix partial matches for locate_mem() and do_cmd()

---
 src/avrpart.c | 28 ++++++++++++++--------------
 src/term.c    | 24 +++++++++++-------------
 2 files changed, 25 insertions(+), 27 deletions(-)

diff --git a/src/avrpart.c b/src/avrpart.c
index 4f03efb2..ac4b8ece 100644
--- a/src/avrpart.c
+++ b/src/avrpart.c
@@ -420,51 +420,51 @@ void avr_free_memalias(AVRMEM_ALIAS *m) {
 AVRMEM_ALIAS *avr_locate_memalias(const AVRPART *p, const char *desc) {
   AVRMEM_ALIAS * m, * match;
   LNODEID ln;
-  int matches, exact;
-  int l;
+  int matches;
+  size_t l;
 
   if(!p || !desc || !p->mem_alias)
     return NULL;
 
   l = strlen(desc);
-  matches = exact = 0;
+  matches = 0;
   match = NULL;
   for (ln=lfirst(p->mem_alias); ln; ln=lnext(ln)) {
     m = ldata(ln);
-    if (strncmp(m->desc, desc, l) == 0) { // Partial initial match
+    if(l && strncmp(m->desc, desc, l) == 0) { // Partial initial match
       match = m;
       matches++;
-      if(m->desc[l] == 0)       // Exact match between arg and memory
-        exact++;
+      if(m->desc[l] == 0)       // Exact match; return straight away
+        return m;
     }
   }
 
-  return exact == 1 || matches == 1? match: NULL;
+  return matches == 1? match: NULL;
 }
 
 AVRMEM *avr_locate_mem_noalias(const AVRPART *p, const char *desc) {
   AVRMEM * m, * match;
   LNODEID ln;
-  int matches, exact;
-  int l;
+  int matches;
+  size_t l;
 
   if(!p || !desc || !p->mem)
     return NULL;
 
   l = strlen(desc);
-  matches = exact = 0;
+  matches = 0;
   match = NULL;
   for (ln=lfirst(p->mem); ln; ln=lnext(ln)) {
     m = ldata(ln);
-    if (strncmp(m->desc, desc, l) == 0) { // Partial initial match
+    if(l && strncmp(m->desc, desc, l) == 0) { // Partial initial match
       match = m;
       matches++;
-      if(m->desc[l] == 0)       // Exact match between arg and memory
-        exact++;
+      if(m->desc[l] == 0)       // Exact match; return straight away
+        return m;
     }
   }
 
-  return exact == 1 || matches == 1? match: NULL;
+  return matches == 1? match: NULL;
 }
 
 
diff --git a/src/term.c b/src/term.c
index ad426fd9..63a9464a 100644
--- a/src/term.c
+++ b/src/term.c
@@ -1235,30 +1235,28 @@ static int tokenize(char *s, char ***argv) {
 
 static int do_cmd(PROGRAMMER *pgm, AVRPART *p, int argc, char *argv[]) {
   int i;
-  int hold;
-  int len;
+  int hold, matches;
+  size_t len;
 
   len = strlen(argv[0]);
-  hold = -1;
+  matches = 0;
   for (i=0; i<NCMDS; i++) {
     if(!*(void (**)(void)) ((char *) pgm + cmd[i].fnoff))
       continue;
-    if (len && strcasecmp(argv[0], cmd[i].name) == 0)
-      return cmd[i].func(pgm, p, argc, argv);
-    if (len && strncasecmp(argv[0], cmd[i].name, len)==0) {
-      if (hold != -1) {
-        pmsg_error("(cmd) command %s is ambiguous\n", argv[0]);
-        return -1;
-      }
+    if(len && strncasecmp(argv[0], cmd[i].name, len)==0) { // Partial initial match
       hold = i;
+      matches++;
+      if(cmd[i].name[len] == 0) { // Exact match
+        matches = 1;
+        break;
+      }
     }
   }
 
-  if (hold != -1)
+  if(matches == 1)
     return cmd[hold].func(pgm, p, argc, argv);
 
-  pmsg_error("(cmd) invalid command %s\n", argv[0]);
-
+  pmsg_error("(cmd) command %s is %s\n", argv[0], matches > 1? "ambiguous": "invalid");
   return -1;
 }