From 3aaa722f72a32f153867efb0a8147da75c7951d2 Mon Sep 17 00:00:00 2001
From: Stefan Rueger <stefan.rueger@urclocks.com>
Date: Tue, 2 Jul 2024 19:48:48 +0100
Subject: [PATCH] Inspect memory lists to decide whether initial chip erase is
 needed

---
 src/libavrdude.h |  2 ++
 src/main.c       | 19 +++++--------------
 src/update.c     | 17 +++++++++++++++--
 3 files changed, 22 insertions(+), 16 deletions(-)

diff --git a/src/libavrdude.h b/src/libavrdude.h
index d67420f9..627d54b1 100644
--- a/src/libavrdude.h
+++ b/src/libavrdude.h
@@ -1318,6 +1318,8 @@ int update_is_readable(const char *fn);
 
 int update_dryrun(const AVRPART *p, UPDATE *upd);
 
+AVRMEM **memory_list(const char *mstr, const AVRPART *p, int *np, int *rwvsoftp, int *dry);
+int memlist_contains_flash(const char *mstr, const AVRPART *p);
 
 #ifdef __cplusplus
 }
diff --git a/src/main.c b/src/main.c
index 6cc74233..9f7dc311 100644
--- a/src/main.c
+++ b/src/main.c
@@ -242,7 +242,7 @@ static void usage(void)
     "  -r                     Reconnect to -P port after \"touching\" it; wait\n"
     "                         400 ms for each -r; needed for some USB boards\n"
     "  -F                     Override invalid signature or initial checks\n"
-    "  -e                     Perform a chip erase\n"
+    "  -e                     Perform a chip erase at the beginning\n"
     "  -O                     Perform RC oscillator calibration (see AVR053)\n"
     "  -t                     Run an interactive terminal when it is its turn\n"
     "  -T <terminal cmd line> Run terminal line when it is its turn\n"
@@ -1686,22 +1686,13 @@ skipopen:
       imsg_info("Each page will be erased before programming it, but no chip erase is performed.\n");
       imsg_info("To disable page erases, specify the -D option; for a chip-erase, use the -e option.\n");
     } else {
-      AVRMEM * m;
-      const char *memname = p->prog_modes & PM_PDI? "application": "flash";
-
       uflags &= ~UF_AUTO_ERASE;
-      for (ln=lfirst(updates); ln; ln=lnext(ln)) {
+      for(ln=lfirst(updates); !erase && ln; ln=lnext(ln)) {
         upd = ldata(ln);
-        if(!upd->memstr)
-          continue;
-        m = avr_locate_mem(p, upd->memstr);
-        if (m == NULL)
-          continue;
-        if(str_eq(m->desc, memname) && upd->op == DEVICE_WRITE) {
+        if(upd->memstr && upd->op == DEVICE_WRITE && memlist_contains_flash(upd->memstr, p)) {
           erase = 1;
-          pmsg_info("Note: %s memory has been specified, an erase cycle will be performed.\n", memname);
-          imsg_info("To disable this feature, specify the -D option.\n");
-          break;
+          pmsg_info("Note: carrying out an erase cycle as flash memory needs programming (-U %s:w:...)\n", upd->memstr);
+          imsg_info("specify the -D option to disable this feature\n");
         }
       }
     }
diff --git a/src/update.c b/src/update.c
index 7829d9fa..80a1326f 100644
--- a/src/update.c
+++ b/src/update.c
@@ -38,7 +38,7 @@
 
 // Is s a multi-memory string (comma-separates list, all, ALL, etc or list subtraction)?
 static int is_multimem(const char *s) {
-  return str_eq(s, "ALL") || str_eq(s, "all") || str_eq(s, "etc") || strpbrk(s, ",\\");
+  return str_eq(s, "ALL") || str_eq(s, "all") || str_eq(s, "etc") || strpbrk(s, "-,\\");
 }
 
 /*
@@ -304,7 +304,7 @@ static int memadd(AVRMEM **mlist, int nm, int not, AVRMEM *m) {
  * to *np and *rwvsoftfail indicating unknown memories for this part. If dry is
  * set then -1 will be written to *dry when a generally unknown memory is used.
  */
-static AVRMEM **memory_list(const char *mstr, const AVRPART *p, int *np, int *rwvsoftp, int *dry) {
+AVRMEM **memory_list(const char *mstr, const AVRPART *p, int *np, int *rwvsoftp, int *dry) {
   int not, nm = (lsize(p->mem) + 1) * ((int) str_numc(mstr, ',') + 1); // Upper limit
   AVRMEM *m, **umemlist = mmt_malloc(nm*sizeof*umemlist);
   char *dstr = mmt_strdup(mstr), *s = dstr, *e;
@@ -363,6 +363,19 @@ done:
   return umemlist;
 }
 
+
+// Returns whether or not the memory list contains a flash memory
+int memlist_contains_flash(const char *mstr, const AVRPART *p) {
+  int ret = 0, nm = 0;
+  AVRMEM **mlist = memory_list(mstr, p, &nm, NULL, NULL);
+  for(int i=0; i<nm; i++)
+    if(mem_is_in_flash(mlist[i]))
+      ret = 1;
+
+   mmt_free(mlist);
+   return ret;
+}
+
 // Basic checks to reveal serious failure before programming (and on autodetect set format)
 int update_dryrun(const AVRPART *p, UPDATE *upd) {
   int known, format_detect, ret = LIBAVRDUDE_SUCCESS;