[PATCH #46] Fixed uninitialized buffer in case of 0 dim for dimstring()

and prevented the compilation of unused functions. Also a comment was
 corrected.

src/frontend/dimens.c

@@ -15,27 +15,36 @@ Author: 1992 David A. Gates, U. C. Berkeley CAD Group
 
 /*
  * Create a string of the form "12,1,10".
+ *
+ * Parameters
+ * dim_data: Array of sizes of dimensions, [12, 1, 10] for the example
+ * n_dim: Number of elements in the array, 3 in the example
+ * retstring: Address of buffer where the string is returned.
+
+ * Remarks
+ * It is assumed that the buffer in retstring is large enough, which for
+ * MAXDIMS, would require MAXDIMS * 11 bytes in the worst case assuming
+ * 32-bit ints. A looser but more general bound only assuming 8-bit bytes
+ * would be MAXDIMS * (3 * sizeof(int) + 1).
  */
 void
-dimstring(int *data, int length, char *retstring)
+dimstring(const int *dim_data, int n_dim, char *retstring)
 {
+    /* Handle case of no dimensions */
+    if (dim_data == (int *) NULL || n_dim < 1) {
+        *retstring = '\0';
+        return;
+    }
+
+    /* Append each dimension */
+    retstring += sprintf(retstring, "%d", dim_data[0]); /* first */
     int  i;
-    char buf[BSIZE_SP];
+    for (i = 1; i < n_dim; i++) { /* rest are prefixed by a comma */
+        retstring += sprintf(retstring, ",%d", dim_data[i]);
+    }
+} /* end of function dimstring */
 
 
-    if (!data || length < 1)
-        retstring = "";
-
-    buf[0] = '\0';
-
-    for (i = 0; i < length; i++)
-        sprintf(buf + strlen(buf), "%d%s", data[i], (i < length - 1) ? "," : "");
-
-    /* XXX Should I return a copy instead? */
-    /* qui ci devo fare una copia */
-    strcpy(retstring, buf);
-}
-
 
 /*
  * Create a string of the form "[12][1][10]" in retstring.
@@ -49,7 +58,7 @@ dimstring(int *data, int length, char *retstring)
  * It is assumed that the buffer in retstring is large enough, which for
  * MAXDIMS, would require MAXDIMS * 12 + 1 bytes in the worst case assuming
  * 32-bit ints. A looser but more general bound only assuming 8-bit bytes
- * would be MAXDIMS * 3 * sizeof(int) + 1.
+ * would be MAXDIMS * (3 * sizeof(int) + 2) + 1.
  */
 void
 indexstring(const int *dim_data, int n_dim, char *retstring)
@@ -74,7 +83,7 @@ indexstring(const int *dim_data, int n_dim, char *retstring)
  * Return 1 when all counters overflow at once.
  */
 int
-incindex(int *counts, int numcounts, int *dims, int numdims)
+incindex(int *counts, int numcounts, const int *dims, int numdims)
 {
     int i, start;
 
@@ -96,22 +105,6 @@ incindex(int *counts, int numcounts, int *dims, int numdims)
 }
 
 
-/*
- * Count number of empty dimensions in an array.
- */
-int
-emptydims(int *data, int length)
-{
-    int i, numempty = 0;
-
-    for (i = 0; i < length; i++)
-        if (data[i] == 0)
-            numempty++;
-
-    return (numempty);
-}
-
-
 /*
  * Read a string of one of the following forms into a dimensions array:
  *  [12][1][10]
@@ -217,6 +210,26 @@ atodims(char *p, int *data, int *outlength)
 }
 
 
+
+#ifdef COMPILE_UNUSED_FUNCTIONS
+/* #ifdef COMPILE_UNUSED_FUNCTIONS added 2019-03-31 */
+/*
+ * Count number of empty dimensions in an array.
+ */
+int
+emptydims(int *data, int length)
+{
+    int i, numempty = 0;
+
+    for (i = 0; i < length; i++)
+        if (data[i] == 0)
+            numempty++;
+
+    return (numempty);
+}
+
+
+
 /*
  * Skip to the first character that cannot be part of a dimension string.
  */
@@ -226,8 +239,10 @@ skipdims(char *p)
     if (!p)
         return NULL;
 
-    while (*p && (*p == '[' || *p == ']' || *p == ',' || isspace_c(*p) || isdigit_c(*p)))
+    while (*p && (*p == '[' || *p == ']' || *p == ',' ||
+            isspace_c(*p) || isdigit_c(*p)))
         p++;
 
     return (p);
 }
+#endif /* COMPILE_UNUSED_FUNCTIONS */

src/frontend/dimens.h

@@ -6,11 +6,15 @@
 #ifndef ngspice_DIMENS_H
 #define ngspice_DIMENS_H
 
-void dimstring(int *data, int length, char *retstring);
+void dimstring(const int *dim_data, int n_dim, char *retstring);
 void indexstring(const int *dim_data, int n_dim, char *retstring);
-int incindex(int *counts, int numcounts, int *dims, int numdims);
+int incindex(int *counts, int numcounts, const int *dims, int numdims);
-int emptydims(int *data, int length);
 int atodims(char *p, int *data, int *outlength);
+
+#ifdef COMPILE_UNUSED_FUNCTIONS
+/* #ifdef COMPILE_UNUSED_FUNCTIONS added 2019-03-31 */
+int emptydims(int *data, int length);
 char *skipdims(char *p);
+#endif
 
 #endif