Silence "may be truncated" warnings

Use memccpy() instead of strncpy() for safe string manipulation.

diff --git a/lib/dns/gen.c b/lib/dns/gen.c
index bbd91b9c6b9ca1d1a53b1edecbe8b5f51c89e26e..1503a6ef22bc2d59ba03b94db553a405ab6102f9 100644 (file)
--- a/lib/dns/gen.c
+++ b/lib/dns/gen.c
@@ -353,7 +353,6 @@ doswitch(const char *name, const char *function, const char *args,
 static void
 insert_into_typenames(int type, const char *typebuf, const char *attr) {
        struct ttnam *ttn = NULL;
-       size_t c;
        int i, n;
        char tmp[256];
 
@@ -379,25 +378,25 @@ insert_into_typenames(int type, const char *typebuf, const char *attr) {
                ttnam_count = i + 1;
        }
 
-       /* XXXMUKS: This is redundant due to the INSIST above. */
-       if (strlen(typebuf) > sizeof(ttn->typebuf) - 1) {
+       char *end = memccpy(ttn->typebuf, typebuf, '\0', sizeof(ttn->typebuf));
+
+       if (end == NULL) {
                fprintf(stderr, "Error:  type name %s is too long\n", typebuf);
                exit(EXIT_FAILURE);
        }
 
-       strncpy(ttn->typebuf, typebuf, sizeof(ttn->typebuf));
-       ttn->typebuf[sizeof(ttn->typebuf) - 1] = '\0';
-
-       strncpy(ttn->macroname, ttn->typebuf, sizeof(ttn->macroname));
-       ttn->macroname[sizeof(ttn->macroname) - 1] = '\0';
+       end = memccpy(ttn->macroname, typebuf, '\0', sizeof(ttn->macroname));
+       if (end == NULL) {
+               fprintf(stderr, "Error:  type name %s is too long\n", typebuf);
+               exit(EXIT_FAILURE);
+       }
 
        ttn->type = type;
-       c = strlen(ttn->macroname);
-       while (c > 0) {
-               if (ttn->macroname[c - 1] == '-') {
-                       ttn->macroname[c - 1] = '_';
+       while (end > ttn->macroname) {
+               if (*end == '-') {
+                       *end = '_';
                }
-               c--;
+               end--;
        }
 
        if (attr == NULL) {
@@ -435,6 +434,7 @@ add(unsigned int rdclass, const char *classbuf, int type, const char *typebuf,
        struct tt *tt, *oldtt;
        struct cc *newcc;
        struct cc *cc, *oldcc;
+       char *end = NULL;
 
        INSIST(strlen(typebuf) < TYPECLASSBUF);
        INSIST(strlen(classbuf) < TYPECLASSBUF);
@@ -451,17 +451,17 @@ add(unsigned int rdclass, const char *classbuf, int type, const char *typebuf,
        newtt->rdclass = rdclass;
        newtt->type = type;
 
-       strncpy(newtt->classbuf, classbuf, sizeof(newtt->classbuf));
-       newtt->classbuf[sizeof(newtt->classbuf) - 1] = '\0';
+       end = memccpy(newtt->classbuf, classbuf, '\0', sizeof(newtt->classbuf));
+       INSIST(end != NULL);
 
-       strncpy(newtt->typebuf, typebuf, sizeof(newtt->typebuf));
-       newtt->typebuf[sizeof(newtt->typebuf) - 1] = '\0';
+       end = memccpy(newtt->typebuf, typebuf, '\0', sizeof(newtt->typebuf));
+       INSIST(end != NULL);
 
        if (strncmp(dirbuf, "./", 2) == 0) {
                dirbuf += 2;
        }
-       strncpy(newtt->dirbuf, dirbuf, sizeof(newtt->dirbuf));
-       newtt->dirbuf[sizeof(newtt->dirbuf) - 1] = '\0';
+       end = memccpy(newtt->dirbuf, dirbuf, '\0', sizeof(newtt->dirbuf));
+       INSIST(end != NULL);
 
        tt = types;
        oldtt = NULL;