SCP: Produce detailed message when REG names are ambiguous.

As discussed in #402 and #398

scp.c

@@ -477,6 +477,7 @@ void fprint_sep (FILE *st, int32 *tokens);
 char *read_line (char *ptr, int32 size, FILE *stream);
 char *read_line_p (const char *prompt, char *ptr, int32 size, FILE *stream);
 REG *find_reg_glob (CONST char *ptr, CONST char **optr, DEVICE **gdptr);
+REG *find_reg_glob_reason (CONST char *cptr, CONST char **optr, DEVICE **gdptr, t_stat *stat);
 char *sim_trim_endspc (char *cptr);
 
 /* Forward references */
@@ -651,6 +652,7 @@ const struct scp_error {
          {"INVREM",  "Invalid remote console command"},
          {"NOTATT",  "Not attached"},
          {"EXPECT",  "Expect matched"},
+         {"AMBREG",  "Ambiguous register name"},
          {"REMOTE",  "remote console command"},
     };
 
@@ -6742,6 +6744,7 @@ int32 opt;
 t_addr low, high;
 t_stat reason;
 DEVICE *tdptr;
+t_stat tstat = SCPE_OK;
 REG *lowr, *highr;
 FILE *ofile;
 
@@ -6781,7 +6784,7 @@ for (gptr = gbuf, reason = SCPE_OK;
 
     if ((lowr = find_reg (gptr, &tptr, tdptr)) ||       /* local reg or */
         (!(sim_opt_out & CMD_OPT_DFT) &&                /* no dflt, global? */
-        (lowr = find_reg_glob (gptr, &tptr, &tdptr)))) {
+        (lowr = find_reg_glob_reason (gptr, &tptr, &tdptr, &tstat)))) {
         low = high = 0;
         if ((*tptr == '-') || (*tptr == ':')) {
             highr = find_reg (tptr + 1, &tptr, tdptr);
@@ -6813,7 +6816,7 @@ for (gptr = gbuf, reason = SCPE_OK;
         (((sim_dfunit->capac == 0) || (flag == EX_E))? 0:
         sim_dfunit->capac - sim_dfdev->aincr), 0);
     if (tptr == NULL)
-        return SCPE_ARG;
+        return (tstat ? tstat : SCPE_ARG);
     if (*tptr && (*tptr++ != ','))
         return SCPE_ARG;
     reason = exdep_addr_loop (ofile, sim_schaptr, flag, cptr, low, high,
@@ -8203,28 +8206,52 @@ return (dptr->flags & DEV_DIS? TRUE: FALSE);
         result  =       pointer to register, NULL if error
         *optr   =       pointer to next character in input string
         *gdptr  =       pointer to device where found
+        *stat   =       pointer to stat for reason
 */
 
-REG *find_reg_glob (CONST char *cptr, CONST char **optr, DEVICE **gdptr)
+REG *find_reg_glob_reason (CONST char *cptr, CONST char **optr, DEVICE **gdptr, t_stat *stat)
 {
 int32 i;
 DEVICE *dptr;
 REG *rptr, *srptr = NULL;
 
+if (stat)
+    *stat = SCPE_OK;
 *gdptr = NULL;
 for (i = 0; (dptr = sim_devices[i]) != 0; i++) {        /* all dev */
     if (dptr->flags & DEV_DIS)                          /* skip disabled */
         continue;
     if ((rptr = find_reg (cptr, optr, dptr))) {         /* found? */
-        if (srptr)                                      /* ambig? err */
+        if (srptr) {                                    /* ambig? err */
-            return NULL;
+            if (stat) {
+                if (sim_show_message) {
+                    if (*stat == SCPE_OK)
+                        sim_printf ("Ambiguous register.  %s appears in devices %s and %s", cptr, (*gdptr)->name, dptr->name);
+                    else
+                        sim_printf (" and %s", dptr->name);
+                    }
+                *stat = SCPE_AMBREG|SCPE_NOMESSAGE;
+                }
+            else
+                return NULL;
+            }
         srptr = rptr;                                   /* save reg */
         *gdptr = dptr;                                  /* save unit */
         }
     }
+if (stat && (*stat != SCPE_OK)) {
+    if (sim_show_message)
+        sim_printf ("\n");
+    srptr = NULL;
+    }
 return srptr;
 }
 
+REG *find_reg_glob (CONST char *cptr, CONST char **optr, DEVICE **gdptr)
+{
+return find_reg_glob_reason (cptr, optr, gdptr, NULL);
+}
+
 /* find_reg             find register matching input string
 
    Inputs:

sim_defs.h

@@ -377,9 +377,10 @@ typedef uint32          t_addr;
 #define SCPE_INVREM     (SCPE_BASE + 43)                /* invalid remote console command */
 #define SCPE_NOTATT     (SCPE_BASE + 44)                /* not attached */
 #define SCPE_EXPECT     (SCPE_BASE + 45)                /* expect matched */
-#define SCPE_REMOTE     (SCPE_BASE + 46)                /* remote console command */
+#define SCPE_AMBREG     (SCPE_BASE + 46)                /* ambiguous register */
+#define SCPE_REMOTE     (SCPE_BASE + 47)                /* remote console command */
 
-#define SCPE_MAX_ERR    (SCPE_BASE + 47)                /* Maximum SCPE Error Value */
+#define SCPE_MAX_ERR    (SCPE_BASE + 48)                /* Maximum SCPE Error Value */
 #define SCPE_KFLAG      0x1000                          /* tti data flag */
 #define SCPE_BREAK      0x2000                          /* tti break flag */
 #define SCPE_NOMESSAGE  0x10000000                      /* message display supression flag */