Adds some missing error handling to PGTYPESnumeric_div() in ecpg's

pgtypeslib: (1) we need to check the return value of sub_abs() (2) we
need to check the return value of 4 calls to digitbuf_alloc().

Per Coverity static analysis performed by EnterpriseDB.

diff --git a/src/interfaces/ecpg/pgtypeslib/numeric.c b/src/interfaces/ecpg/pgtypeslib/numeric.c
index 4e73d24e7109a5df62642b41f7868c51467a3b38..e0a954ccad1f3ae3ce2d520994dfba3ee406a0ce 100644 (file)
--- a/src/interfaces/ecpg/pgtypeslib/numeric.c
+++ b/src/interfaces/ecpg/pgtypeslib/numeric.c
@@ -1096,6 +1096,8 @@ PGTYPESnumeric_div(numeric *var1, numeric *var2, numeric *result)
        int                     stat = 0;
        int                     rscale;
        int                     res_dscale = select_div_scale(var1, var2, &rscale);
+       int                     err = -1;
+       NumericDigit *tmp_buf;
 
        /*
         * First of all division by zero check
@@ -1143,6 +1145,8 @@ PGTYPESnumeric_div(numeric *var1, numeric *var2, numeric *result)
        divisor[1].rscale = var2->ndigits;
        divisor[1].sign = NUMERIC_POS;
        divisor[1].buf = digitbuf_alloc(ndigits_tmp);
+       if (divisor[1].buf == NULL)
+               goto done;
        divisor[1].digits = divisor[1].buf;
        divisor[1].digits[0] = 0;
        memcpy(&(divisor[1].digits[1]), var2->digits, ndigits_tmp - 1);
@@ -1155,14 +1159,21 @@ PGTYPESnumeric_div(numeric *var1, numeric *var2, numeric *result)
        dividend.rscale = var1->ndigits;
        dividend.sign = NUMERIC_POS;
        dividend.buf = digitbuf_alloc(var1->ndigits);
+       if (dividend.buf == NULL)
+               goto done;
        dividend.digits = dividend.buf;
        memcpy(dividend.digits, var1->digits, var1->ndigits);
 
        /*
-        * Setup the result
+        * Setup the result. Do the allocation in a temporary buffer
+        * first, so we don't free result->buf unless we have successfully
+        * allocated a buffer to replace it with.
         */
+       tmp_buf = digitbuf_alloc(res_ndigits + 2);
+       if (tmp_buf == NULL)
+               goto done;
        digitbuf_free(result->buf);
-       result->buf = digitbuf_alloc(res_ndigits + 2);
+       result->buf = tmp_buf;
        res_digits = result->buf;
        result->digits = res_digits;
        result->ndigits = res_ndigits;
@@ -1201,6 +1212,8 @@ PGTYPESnumeric_div(numeric *var1, numeric *var2, numeric *result)
 
                                memcpy(&divisor[guess], &divisor[1], sizeof(numeric));
                                divisor[guess].buf = digitbuf_alloc(divisor[guess].ndigits);
+                               if (divisor[guess].buf == NULL)
+                                       goto done;
                                divisor[guess].digits = divisor[guess].buf;
                                for (i = divisor[1].ndigits - 1; i >= 0; i--)
                                {
@@ -1233,7 +1246,8 @@ PGTYPESnumeric_div(numeric *var1, numeric *var2, numeric *result)
                if (guess == 0)
                        continue;
 
-               sub_abs(&dividend, &divisor[guess], &dividend);
+               if (sub_abs(&dividend, &divisor[guess], &dividend) != 0)
+                       goto done;
 
                first_nextdigit = dividend.weight - weight_tmp;
                first_have = 0;
@@ -1269,15 +1283,23 @@ PGTYPESnumeric_div(numeric *var1, numeric *var2, numeric *result)
        if (result->ndigits == 0)
                result->sign = NUMERIC_POS;
 
+       result->dscale = res_dscale;
+       err = 0;        /* if we've made it this far, return success */
+
+done:
        /*
         * Tidy up
         */
-       digitbuf_free(dividend.buf);
+       if (dividend.buf != NULL)
+               digitbuf_free(dividend.buf);
+
        for (i = 1; i < 10; i++)
-               digitbuf_free(divisor[i].buf);
+       {
+               if (divisor[i].buf != NULL)
+                       digitbuf_free(divisor[i].buf);
+       }
 
-       result->dscale = res_dscale;
-       return 0;
+       return err;
 }