fix an endless loop waiting for y/n when the input is at EOF

reported by Calin Andrian
  Subject: [Ngspice-devel] Invaild number bug

src/frontend/numparam/general.h

@@ -42,7 +42,7 @@ bool alfanum(char c);
 char *stupcase(char *s);
 
 /***** primitive input-output ***/
-void rs(SPICE_DSTRINGPTR s);
+int yes_or_no(void);
 char rc(void);
 
 int freadstr(FILE *f, SPICE_DSTRINGPTR dstr_p);

src/frontend/numparam/mystring.c

@@ -22,7 +22,35 @@
 #include "ngspice/fteext.h" /* controlled_exit() */
 
 
-/***** primitive input-output ***/
+/*
+ * fetch a human answer to a y/n question from stdin
+ * insist on a single non white-space char on a '\n' terminated line
+ * return this char or '\n' or EOF
+ * return '\0' if the answer doesn't fit this pattern
+ */
+
+int
+yes_or_no(void)
+{
+    int first;
+
+    do {
+        first = getchar();
+        if (first == '\n' || first == EOF)
+            return first;
+    } while (isspace(first));
+
+    for (;;) {
+        int c = getchar();
+        if (c == EOF)
+            return c;
+        if (c == '\n')
+            return tolower(first);
+        if (!isspace(c))
+            first = '\0';
+    }
+}
+
 
 bool
 ci_prefix(const char *p, const char *s)
@@ -39,22 +67,6 @@ ci_prefix(const char *p, const char *s)
 }
 
 
-void
-rs(SPICE_DSTRINGPTR dstr_p)
-{
-    /* basic line input, limit= 80 chars */
-    char c;
-
-    spice_dstring_reinit(dstr_p);
-    do
-    {
-        c = (char) fgetc(stdin);
-        cadd(dstr_p, c);
-    }
-    while (!((c == '\r') || (c == '\n')));
-}
-
-
 /*******  Strings ************
  *  are 0-terminated char arrays with a 2-byte trailer: max length.
  *  the string mini-library is "overflow-safe" under these conditions:

src/frontend/numparam/nupatest.c

@@ -141,26 +141,6 @@ void gluepluslines( int imax)
   }
 }
 
-#if 0	/* sjb - this is in mystring.c */
-void rs(char * s) /*  78 coumn limit */
-{
-  int i; 
-  unsigned char done; 
-  char c;
-  int max=maxlen(s);
-  if ( max>78 ) { max=78 ;}
-  i=0; done=0; 
-  scopy(s,"");
-  while ( ! done ) {
-    c=fgetc(stdin);
-    if ( (c>=' ')&&(c<='~') && (i<max) ) { 
-      cadd(s,c); Inc(i); 
-    }
-    done= (c=='\n') || (c=='\r');
-  }
-}
-#endif
-
 void fwrites(FILE * f, char * s)
 { 
   fputs(s,f); 

src/frontend/numparam/spicenum.c

@@ -29,6 +29,8 @@ Todo:
 #include "ngspice/fteext.h" /* controlled_exit() */
 
 
+extern bool ft_batchmode;
+
 void dump_symbols(tdico *dico_p);
 
 char *nupa_inst_name;
@@ -498,7 +500,6 @@ static void
 nupa_done(void)
 {
     /* int i; not needed so far, see below */
-    char *reply;                /* user reply */
     SPICE_DSTRING rep;          /* dynamic report */
     int dictsize, nerrors;
 
@@ -530,12 +531,17 @@ nupa_done(void)
         nadd(&rep, nerrors);
         cadd(&rep, '\n');
         printf("%s", spice_dstring_value(&rep));
-        printf("Numparam expansion errors: Run Spice anyway? y/n ?\n");
-        spice_dstring_reinit(&rep);
-        rs(&rep);
-        reply = spice_dstring_value(&rep);
-        if (upcase(reply[0]) != 'Y')
+        if (ft_batchmode)
             controlled_exit(EXIT_FAILURE);
+        for (;;) {
+            int c;
+            printf("Numparam expansion errors: Run Spice anyway? y/n ?\n");
+            c = yes_or_no();
+            if (c == 'n' || c == EOF)
+                controlled_exit(EXIT_FAILURE);
+            if (c == 'y')
+                break;
+        }
     }
 
     linecountS = 0;