Avoid unnecessary use of strncpy in a couple of places in ecpg.

Use of strncpy with a length limit based on the source, rather than
the destination, is non-idiomatic and draws warnings from gcc 8.
Replace with memcpy, which does exactly the same thing in these cases,
but with less chance for confusion.

Backpatch to all supported branches.

Discussion: https://postgr.es/m/21789.1529170195@sss.pgh.pa.us

diff --git a/src/interfaces/ecpg/ecpglib/descriptor.c b/src/interfaces/ecpg/ecpglib/descriptor.c
index f38bf343f0b75cf318694eff3a562d94cbd91ea2..8fdf5606c09cf95d340b4fd8c7cde1c5729fb710 100644 (file)
--- a/src/interfaces/ecpg/ecpglib/descriptor.c
+++ b/src/interfaces/ecpg/ecpglib/descriptor.c
@@ -218,7 +218,7 @@ get_char_item(int lineno, void *var, enum ECPGttype vartype, char *value, int va
                (struct ECPGgeneric_varchar *) var;
 
                if (varcharsize == 0)
-                   strncpy(variable->arr, value, strlen(value));
+                   memcpy(variable->arr, value, strlen(value));
                else
                    strncpy(variable->arr, value, varcharsize);
 

diff --git a/src/interfaces/ecpg/pgtypeslib/common.c b/src/interfaces/ecpg/pgtypeslib/common.c
index ae29b6c4ab85cee5ebc2c6053b1e1d11defab489..2adb6809e2013ae313836b7778a0632f1233820d 100644 (file)
--- a/src/interfaces/ecpg/pgtypeslib/common.c
+++ b/src/interfaces/ecpg/pgtypeslib/common.c
@@ -42,10 +42,8 @@ pgtypes_fmt_replace(union un_fmt_comb replace_val, int replace_type, char **outp
            i = strlen(replace_val.str_val);
            if (i + 1 <= *pstr_len)
            {
-               /*
-                * copy over i + 1 bytes, that includes the tailing terminator
-                */
-               strncpy(*output, replace_val.str_val, i + 1);
+               /* include trailing terminator in what we copy */
+               memcpy(*output, replace_val.str_val, i + 1);
                *pstr_len -= i;
                *output += i;
                if (replace_type == PGTYPES_TYPE_STRING_MALLOCED)